MC9S12XHZ512
Data Sheet
Covers
MC9S12XHZ384, MC9S12XHZ256
HCS12X
Microcontrollers
MC9S12XHZ512
Rev. 1.06
10/2010
freescale.com
To provide the most up-to-date information, the revision of our documents on the World Wide Web will be
the most current. Your printed copy may be an earlier revision. To verify you have the latest information
available, refer to:
http://freescale.com/
The following revision history table summarizes changes contained in this document. This document
contains information for all constituent modules, with the exception of the S12X CPU. For S12X CPU
information please refer to CPU12XV2 in the CPU12/CPU12X Reference Manual.
Revision History
Date
Revision
Level
January 5, 2006
01.00
New Book
April 20, 2006
01.01
Updated block guide versions
July 28, 2006
01.02
Made minor corrections
January 8, 2007
01.03
Added MC9S12XHZ384 and MC9S12XHZ256
August 20, 2007
01.04
Updated slew rates
November 4, 2008
01.05
Corrected typos on pinout diagram
October 14, 2010
01.06
Added PartID. Minor updates to ECT, SCI, IIC and XGATE sections.
Description
List of Chapters
Chapter 1
MC9S12XHZ Family Device Overview . . . . . . . . . . . . . . . . . . . 21
Chapter 2
Port Integration Module (S12XHZPIMV1) . . . . . . . . . . . . . . . . . 57
Chapter 3
512 Kbyte Flash Module (S12XFTX512K4V3). . . . . . . . . . . . . 131
Chapter 4
4 Kbyte EEPROM Module (S12XEETX4KV2) . . . . . . . . . . . . . 175
Chapter 5
XGATE (S12XGATEV2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Chapter 6
Security (S12X9SECV2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Chapter 7
Clocks and Reset Generator (S12CRGV6) . . . . . . . . . . . . . . . 331
Chapter 8
Pierce Oscillator (S12XOSCLCPV1) . . . . . . . . . . . . . . . . . . . . 371
Chapter 9
Analog-to-Digital Converter (ATD10B16CV4) . . . . . . . . . . . . 377
Chapter 10
Liquid Crystal Display (LCD32F4BV1) . . . . . . . . . . . . . . . . . . 411
Chapter 11
Motor Controller (MC10B12CV2). . . . . . . . . . . . . . . . . . . . . . . 429
Chapter 12
Stepper Stall Detector (SSDV1). . . . . . . . . . . . . . . . . . . . . . . . 461
Chapter 13
Inter-Integrated Circuit (IICV3) . . . . . . . . . . . . . . . . . . . . . . . . 479
Chapter 14
Freescale’s Scalable Controller Area Network (MSCANV3) . 507
Chapter 15
Serial Communication Interface (SCIV5) . . . . . . . . . . . . . . . . 561
Chapter 16
Serial Peripheral Interface (SPIV4) . . . . . . . . . . . . . . . . . . . . . 599
Chapter 17
Periodic Interrupt Timer (PIT24B4CV1) . . . . . . . . . . . . . . . . . 625
Chapter 18
Pulse-Width Modulator (PWM8B8CV1). . . . . . . . . . . . . . . . . . 639
Chapter 19
Enhanced Capture Timer (ECT16B8CV3). . . . . . . . . . . . . . . . 671
Chapter 20
Voltage Regulator (VREG3V3V5) . . . . . . . . . . . . . . . . . . . . . . 725
Chapter 21
Background Debug Module (S12XBDMV2) . . . . . . . . . . . . . . 739
Chapter 22
S12X Debug (S12XDBGV3) Module . . . . . . . . . . . . . . . . . . . . 765
Chapter 23
External Bus Interface (S12XEBIV3) . . . . . . . . . . . . . . . . . . . . 807
Chapter 24
Interrupt (S12XINTV1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 831
Chapter 25
Memory Mapping Control (S12XMMCV3) . . . . . . . . . . . . . . . . 849
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Appendix A Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 891
Appendix B Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 935
Appendix C PCB Layout Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 938
Appendix D Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 941
Appendix E Detailed Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 942
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Table of Contents
Chapter 1
MC9S12XHZ Family Device Overview
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
1.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
1.1.4 Device Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
1.1.5 Part ID Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
1.2.1 Device Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
1.2.2 Signal Properties Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
1.2.3 Detailed Signal Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
1.2.4 Power Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
System Clock Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Chip Configuration Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.5.1 User Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.5.2 Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
1.5.3 Freeze Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Resets and Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
1.6.1 Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
1.6.2 Effects of Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
COP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
ATD External Trigger Input Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Chapter 2
Port Integration Module (S12XHZPIMV1)
2.1
2.2
2.3
lntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
2.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
2.1.2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
2.3.1 Port A and Port B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
2.3.2 Port C and Port D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
2.3.3 Port E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
2.3.4 Port K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
2.3.5 Miscellaneous registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
2.3.6 Port AD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
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2.4
2.5
2.6
2.3.7 Port L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
2.3.8 Port M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
2.3.9 Port P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
2.3.10 Port S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
2.3.11 Port T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
2.3.12 Port U . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
2.3.13 Port V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
2.3.14 Port W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
2.4.1 I/O Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
2.4.2 Input Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
2.4.3 Data Direction Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
2.4.4 Reduced Drive Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
2.4.5 Pull Device Enable Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
2.4.6 Polarity Select Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
2.4.7 Pin Configuration Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
2.5.1 Reset Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
2.6.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
2.6.2 Interrupt Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
2.6.3 Operation in Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Chapter 3
512 Kbyte Flash Module (S12XFTX512K4V3)
3.1
3.2
3.3
3.4
3.5
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
3.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
3.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
3.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
3.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
3.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
3.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
3.4.1 Flash Command Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
3.4.2 Flash Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
3.4.3 Illegal Flash Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
3.5.1 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
3.5.2 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
3.5.3 Background Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
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3.6
3.7
3.8
Flash Module Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
3.6.1 Unsecuring the MCU using Backdoor Key Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
3.6.2 Unsecuring the MCU in Special Single Chip Mode using BDM . . . . . . . . . . . . . . . . . 172
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
3.7.1 Flash Reset Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
3.7.2 Reset While Flash Command Active . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
3.8.1 Description of Flash Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Chapter 4
4 Kbyte EEPROM Module (S12XEETX4KV2)
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
4.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
4.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
4.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
4.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
4.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
4.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
4.4.1 EEPROM Command Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
4.4.2 EEPROM Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
4.4.3 Illegal EEPROM Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
4.5.1 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
4.5.2 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
4.5.3 Background Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
EEPROM Module Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
4.6.1 Unsecuring the MCU in Special Single Chip Mode using BDM . . . . . . . . . . . . . . . . . 206
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
4.7.1 EEPROM Reset Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
4.7.2 Reset While EEPROM Command Active . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
4.8.1 Description of EEPROM Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Chapter 5
XGATE (S12XGATEV2)
5.1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
5.1.1 Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
5.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
5.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
7
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
5.3.1 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
5.4.1 XGATE RISC Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
5.4.2 Programmer’s Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
5.4.3 Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
5.4.4 Semaphores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
5.4.5 Software Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
5.5.1 Incoming Interrupt Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
5.5.2 Outgoing Interrupt Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
5.6.1 Debug Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
5.6.2 Entering Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
5.6.3 Leaving Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
5.8.1 Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
5.8.2 Instruction Summary and Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
5.8.3 Cycle Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
5.8.4 Thread Execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
5.8.5 Instruction Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
5.8.6 Instruction Coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Initialization and Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
5.9.1 Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
5.9.2 Code Example (Transmit "Hello World!" on SCI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Chapter 6
Security (S12X9SECV2)
6.1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
6.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
6.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
6.1.3 Securing the Microcontroller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
6.1.4 Operation of the Secured Microcontroller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
6.1.5 Unsecuring the Microcontroller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
6.1.6 Reprogramming the Security Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
6.1.7 Complete Memory Erase (Special Modes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
MC9S12XHZ512 Data Sheet, Rev. 1.06
8
Freescale Semiconductor
Chapter 7
Clocks and Reset Generator (S12CRGV6)
7.1
7.2
7.3
7.4
7.5
7.6
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
7.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
7.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
7.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
7.2.1 VDDPLL and VSSPLL — Operating and Ground Voltage Pins . . . . . . . . . . . . . . . . . . . . 334
7.2.2 XFC — External Loop Filter Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
7.2.3 RESET — Reset Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
7.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
7.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
7.4.1 Functional Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
7.4.2 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
7.4.3 Low Power Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
7.5.1 Description of Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
7.5.2 Clock Monitor Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
7.5.3 Computer Operating Properly Watchdog (COP) Reset . . . . . . . . . . . . . . . . . . . . . . . . . 367
7.5.4 Power On Reset, Low Voltage Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368
7.6.1 Real Time Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368
7.6.2 PLL Lock Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
7.6.3 Self Clock Mode Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Chapter 8
Pierce Oscillator (S12XOSCLCPV1)
8.1
8.2
8.3
8.4
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
8.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
8.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
8.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
8.2.1 VDDPLL and VSSPLL — Operating and Ground Voltage Pins . . . . . . . . . . . . . . . . . . . . 372
8.2.2 EXTAL and XTAL — Input and Output Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
8.2.3 XCLKS — Input Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
8.4.1 Gain Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
8.4.2 Clock Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
8.4.3 Wait Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
9
8.4.4 Stop Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
Chapter 9
Analog-to-Digital Converter (ATD10B16CV4)
Block Description
9.1
9.2
9.3
9.4
9.5
9.6
9.7
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
9.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
9.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
9.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
9.2.1 ANx (x = 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) — Analog Input Channel x Pins
379
9.2.2 ETRIG3, ETRIG2, ETRIG1, ETRIG0 — External Trigger Pins . . . . . . . . . . . . . . . . . 379
9.2.3 VRH, VRL — High Reference Voltage Pin, Low Reference Voltage Pin . . . . . . . . . . . . 379
9.2.4 VDDA, VSSA — Analog Circuitry Power Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . 379
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
9.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
9.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404
9.4.1 Analog Sub-block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404
9.4.2 Digital Sub-Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
9.4.3 Operation in Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406
Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
9.5.1 Setting up and starting an A/D conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
9.5.2 Aborting an A/D conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409
Chapter 10
Liquid Crystal Display (LCD32F4BV1) Block Description
10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
10.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
10.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
10.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
10.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.2.1 BP[3:0] — Analog Backplane Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.2.2 FP[31:0] — Analog Frontplane Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.2.3 VLCD — LCD Supply Voltage Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
10.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415
MC9S12XHZ512 Data Sheet, Rev. 1.06
10
Freescale Semiconductor
10.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
10.4.1 LCD Driver Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
10.4.2 Operation in Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
10.4.3 Operation in Pseudo Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
10.4.4 Operation in Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
10.4.5 LCD Waveform Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
10.5 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428
10.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428
Chapter 11
Motor Controller (MC10B12CV2) Block Description
11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
11.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
11.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
11.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 431
11.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432
11.2.1 M0C0M/M0C0P/M0C1M/M0C1P — PWM Output Pins for Motor 0 . . . . . . . . . . . . 432
11.2.2 M1C0M/M1C0P/M1C1M/M1C1P — PWM Output Pins for Motor 1 . . . . . . . . . . . . 433
11.2.3 M2C0M/M2C0P/M2C1M/M2C1P — PWM Output Pins for Motor 2 . . . . . . . . . . . . 433
11.2.4 M3C0M/M3C0P/M3C1M/M3C1P — PWM Output Pins for Motor 3 . . . . . . . . . . . . 433
11.2.5 M4C0M/M4C0P/M4C1M/M4C1P — PWM Output Pins for Motor 4 . . . . . . . . . . . . 433
11.2.6 M5C0M/M5C0P/M5C1M/M5C1P — PWM Output Pins for Motor 5 . . . . . . . . . . . . 433
11.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434
11.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434
11.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436
11.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442
11.4.1 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442
11.4.2 PWM Duty Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454
11.4.3 Motor Controller Counter Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454
11.4.4 Output Switching Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455
11.4.5 Operation in Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
11.4.6 Operation in Stop and Pseudo-Stop Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
11.5 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
11.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
11.6.1 Timer Counter Overflow Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
11.7 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 457
11.7.1 Code Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 457
Chapter 12
Stepper Stall Detector (SSDV1) Block Description
12.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461
12.1.1 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461
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12.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461
12.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 462
12.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463
12.2.1 COSxM/COSxP — Cosine Coil Pins for Motor x . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463
12.2.2 SINxM/SINxP — Sine Coil Pins for Motor x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463
12.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
12.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
12.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
12.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472
12.4.1 Return to Zero Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472
12.4.2 Full Step States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473
12.4.3 Operation in Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476
12.4.4 Stall Detection Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476
Chapter 13
Inter-Integrated Circuit (IICV3) Block Description
13.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479
13.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479
13.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 481
13.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 481
13.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
13.2.1 IIC_SCL — Serial Clock Line Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
13.2.2 IIC_SDA — Serial Data Line Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
13.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
13.3.1 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
13.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494
13.4.1 I-Bus Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494
13.4.2 Operation in Run Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
13.4.3 Operation in Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
13.4.4 Operation in Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
13.5 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
13.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
13.7 Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500
13.7.1 IIC Programming Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500
Chapter 14
Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
14.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508
14.1.2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508
14.1.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509
14.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509
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14.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
14.2.1 RXCAN — CAN Receiver Input Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
14.2.2 TXCAN — CAN Transmitter Output Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
14.2.3 CAN System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
14.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511
14.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511
14.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513
14.3.3 Programmer’s Model of Message Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 532
14.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
14.4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
14.4.2 Message Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
14.4.3 Identifier Acceptance Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 546
14.4.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552
14.4.5 Low-Power Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554
14.4.6 Reset Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558
14.4.7 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558
14.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560
14.5.1 MSCAN initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560
14.5.2 Bus-Off Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560
Chapter 15
Serial Communication Interface (S12SCIV5)
15.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561
15.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 561
15.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562
15.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562
15.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563
15.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564
15.2.1 TXD — Transmit Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564
15.2.2 RXD — Receive Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564
15.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564
15.3.1 Module Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564
15.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 565
15.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577
15.4.1 Infrared Interface Submodule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 578
15.4.2 LIN Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 578
15.4.3 Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 579
15.4.4 Baud Rate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 580
15.4.5 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 581
15.4.6 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 586
15.4.7 Single-Wire Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594
15.4.8 Loop Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
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15.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
15.5.1 Reset Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
15.5.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
15.5.3 Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 596
15.5.4 Recovery from Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 598
15.5.5 Recovery from Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 598
Chapter 16
Serial Peripheral Interface (S12SPIV4)
16.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 599
16.1.1 Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 599
16.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 599
16.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 599
16.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600
16.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
16.2.1 MOSI — Master Out/Slave In Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
16.2.2 MISO — Master In/Slave Out Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
16.2.3 SS — Slave Select Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
16.2.4 SCK — Serial Clock Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
16.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
16.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
16.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603
16.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 612
16.4.1 Master Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
16.4.2 Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 614
16.4.3 Transmission Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 615
16.4.4 SPI Baud Rate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 619
16.4.5 Special Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 619
16.4.6 Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 621
16.4.7 Low Power Mode Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 621
Chapter 17
Periodic Interrupt Timer (S12PIT24B4CV1)
17.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
17.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
17.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
17.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
17.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626
17.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626
17.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 627
17.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 636
17.4.1 Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 636
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
17.4.2 Interrupt Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637
17.4.3 Hardware Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 638
17.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 638
17.5.1 Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 638
17.5.2 Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 638
17.5.3 Flag Clearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 638
Chapter 18
Pulse-Width Modulator (S12PWM8B8CV1)
18.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
18.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
18.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 639
18.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640
18.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640
18.2.1 PWM7 — PWM Channel 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640
18.2.2 PWM6 — PWM Channel 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 640
18.2.3 PWM5 — PWM Channel 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.2.4 PWM4 — PWM Channel 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.2.5 PWM3 — PWM Channel 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.2.6 PWM3 — PWM Channel 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.2.7 PWM3 — PWM Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.2.8 PWM3 — PWM Channel 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
18.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642
18.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657
18.4.1 PWM Clock Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657
18.4.2 PWM Channel Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 660
18.5 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 668
18.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 669
Chapter 19
Enhanced Capture Timer (ECT16B8CV3)
19.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671
19.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671
19.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 672
19.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 673
19.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 673
19.2.1 IOC7 — Input Capture and Output Compare Channel 7 . . . . . . . . . . . . . . . . . . . . . . . . 673
19.2.2 IOC6 — Input Capture and Output Compare Channel 6 . . . . . . . . . . . . . . . . . . . . . . . . 673
19.2.3 IOC5 — Input Capture and Output Compare Channel 5 . . . . . . . . . . . . . . . . . . . . . . . . 674
19.2.4 IOC4 — Input Capture and Output Compare Channel 4 . . . . . . . . . . . . . . . . . . . . . . . . 674
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
15
19.2.5 IOC3 — Input Capture and Output Compare Channel 3 . . . . . . . . . . . . . . . . . . . . . . . . 674
19.2.6 IOC2 — Input Capture and Output Compare Channel 2 . . . . . . . . . . . . . . . . . . . . . . . . 674
19.2.7 IOC1 — Input Capture and Output Compare Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . 674
19.2.8 IOC0 — Input Capture and Output Compare Channel 0 . . . . . . . . . . . . . . . . . . . . . . . . 674
19.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674
19.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674
19.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674
19.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 710
19.4.1 Enhanced Capture Timer Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 717
19.4.2 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 721
19.4.3 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722
Chapter 20
Voltage Regulator (S12VREG3V3V5)
20.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725
20.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725
20.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725
20.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 726
20.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728
20.2.1 VDDR — Regulator Power Input Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 728
20.2.2 VDDA, VSSA — Regulator Reference Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . 728
20.2.3 VDD, VSS — Regulator Output1 (Core Logic) Pins . . . . . . . . . . . . . . . . . . . . . . . . . . 728
20.2.4 VDDPLL, VSSPLL — Regulator Output2 (PLL) Pins . . . . . . . . . . . . . . . . . . . . . . . . . 729
20.2.5 VREGEN — Optional Regulator Enable Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
20.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
20.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 729
20.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 730
20.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735
20.4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735
20.4.2 Regulator Core (REG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735
20.4.3 Low-Voltage Detect (LVD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
20.4.4 Power-On Reset (POR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
20.4.5 Low-Voltage Reset (LVR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
20.4.6 Regulator Control (CTRL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
20.4.7 Autonomous Periodical Interrupt (API) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 736
20.4.8 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 737
20.4.9 Description of Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 737
20.4.10Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 737
Chapter 21
Background Debug Module (S12XBDMV2)
21.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 739
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
21.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 739
21.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 740
21.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741
21.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741
21.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 742
21.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 742
21.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 742
21.3.3 Family ID Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 747
21.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 747
21.4.1 Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 748
21.4.2 Enabling and Activating BDM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 748
21.4.3 BDM Hardware Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 749
21.4.4 Standard BDM Firmware Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 750
21.4.5 BDM Command Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 751
21.4.6 BDM Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 753
21.4.7 Serial Interface Hardware Handshake Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 756
21.4.8 Hardware Handshake Abort Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 758
21.4.9 SYNC — Request Timed Reference Pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 761
21.4.10Instruction Tracing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 762
21.4.11Serial Communication Time Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 763
Chapter 22
S12X Debug (S12XDBGV3) Module
22.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 765
22.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 765
22.1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 766
22.1.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 766
22.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 767
22.1.5 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768
22.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768
22.3 Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768
22.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 768
22.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 770
22.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 786
22.4.1 S12XDBG Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 787
22.4.2 Comparator Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 787
22.4.3 Trigger Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 791
22.4.4 State Sequence Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 792
22.4.5 Trace Buffer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 793
22.4.6 Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 801
22.4.7 Breakpoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 802
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
17
Chapter 23
External Bus Interface (S12XEBIV3)
23.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 807
23.1.1 Glossary or Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 808
23.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 808
23.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 808
23.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 810
23.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 810
23.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 812
23.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 812
23.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 812
23.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 816
23.4.1 Operating Modes and External Bus Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 816
23.4.2 Internal Visibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 817
23.4.3 Accesses to Port Replacement Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 821
23.4.4 Stretched External Bus Accesses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 821
23.4.5 Data Select and Data Direction Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 822
23.4.6 Low-Power Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824
23.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824
23.5.1 Normal Expanded Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 825
23.5.2 Emulation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 826
Chapter 24
Interrupt (S12XINTV1)
24.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 831
24.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 832
24.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 832
24.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 832
24.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 834
24.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 835
24.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 835
24.3.1 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 836
24.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 843
24.4.1 S12X Exception Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 843
24.4.2 Interrupt Prioritization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 843
24.4.3 XGATE Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 844
24.4.4 Priority Decoders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 844
24.4.5 Reset Exception Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 845
24.4.6 Exception Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 845
24.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 846
24.5.1 Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 846
24.5.2 Interrupt Nesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 846
MC9S12XHZ512 Data Sheet, Rev. 1.06
18
Freescale Semiconductor
24.5.3 Wake Up from Stop or Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 847
Chapter 25
Memory Mapping Control (S12XMMCV3)
25.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 849
25.1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 850
25.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 850
25.1.3 S12X Memory Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 851
25.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 851
25.1.5 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 852
25.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 852
25.3 Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 854
25.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 854
25.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855
25.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 869
25.4.1 MCU Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 869
25.4.2 Memory Map Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 870
25.4.3 Chip Access Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 880
25.4.4 Chip Bus Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 882
25.4.5 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 883
25.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 883
25.5.1 CALL and RTC Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 883
25.5.2 Port Replacement Registers (PRRs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 884
25.5.3 On-Chip ROM Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 886
Appendix A
Electrical Characteristics
A.1
A.2
A.3
A.4
A.5
A.6
A.7
A.8
A.9
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 891
ATD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 903
NVM, Flash, and EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 907
Voltage Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 912
Reset, Oscillator, and PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 913
LCD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 919
MSCAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 920
SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 920
External Bus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 924
Appendix B
Package Information
B.1 144-Pin LQFP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 936
B.2 112-Pin LQFP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 937
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
19
Appendix C
PCB Layout Guidelines
Appendix D
Ordering Information
Appendix E
Detailed Register Map
MC9S12XHZ512 Data Sheet, Rev. 1.06
20
Freescale Semiconductor
Chapter 1
MC9S12XHZ Family Device Overview
1.1
Introduction
Targeted at automotive instrumentation applications, the MC912XHZ family of microcontrollers is a fully
pin-compatible extension to the existing MC9S12HZ family. It offers not only a larger memory but also
incorporates all the architectural benefits of the new S12X-based family to deliver significantly higher
performance. The MC9S12XHZ family retains the low cost, power consumption, EMC and code-size
efficiency advantages currently associated with the MC9S12 products.
Based around S12X core, the MC912XHZ family runs 16-bit wide accesses without wait states for all
peripherals and memories. The MC912XHZ family also features a new flexible interrupt handler, which
allows multilevel nested interrupts.
The MC912XHZ family features the performance boosting XGATE co-processor. The XGATE is
programmable in “C” language and runs at twice the bus frequency of the S12. Its instruction set is
optimized for data movement, logic and bit manipulation instructions. Any peripheral module can be
serviced by the XGATE.
The MC912XHZ family contains up to 512K bytes of Freescale Semiconductor’s industry leading, full
automotive qualified Split-Gate Flash memory, with 4K bytes of additional integrated data EEPROM and
up to 32K bytes of static RAM.
The MC912XHZ family features a 32x4 liquid crystal display (LCD) controller/driver and a motor pulse
width modulator (MC) consisting of up to 24 high current outputs suited to drive six stepper motors with
stall detectors (SSD) to simultaneously calibrate the pointer reset position of each motor. It also features
two MSCAN modules, each with a FIFO receiver buffer arrangement, and input filters optimized for
Gateway applications handling numerous message identifiers.
In addition, the MC912XHZ family is composed of standard on-chip peripherals including two
asynchronous serial communications interfaces (SCI0 and SCI1), one serial peripheral interface (SPI), two
IIC-bus interface (IIC0 and IIC1), an 8-channel 16-bit enhanced capture timer (ECT), a 16-channel, 10-bit
analog-to-digital converter (ADC), and one 8-channel pulse width modulator (PWM).
The inclusion of a PLL circuit allows power consumption and performance to be adjusted to suit
operational requirements. The new fast-exit from STOP mode feature can further improve system power
consumption. In addition to the I/O ports available in each module, 8 general-purpose I/O pins are
available with interrupt and wake-up capability from stop or wait mode.
The MC912XHZ family is available in 112-pin LQFP and 144-pin LQFP packages. The 144-pin LQFP
package option provides a full 16-bit wide non-multiplexed external bus interface.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
21
Chapter 1 MC9S12XHZ Family Device Overview
1.1.1
•
•
•
•
•
•
•
Features
HCS12X Core
— 16-bit HCS12X CPU
– Upward compatible with MC9S12 instruction set
– Interrupt stacking and programmer’s model identical to MC9S12
– Instruction queue
– Enhanced indexed addressing
– Enhanced instruction set
— EBI (external bus interface)
— MMC (module mapping control)
— INT (interrupt controller)
— DBG (debug module to monitor HCS12X CPU and XGATE bus activity)
— BDM (background debug mode)
XGATE (peripheral coprocessor)
— Parallel processing module off loads the CPU by providing high-speed data processing and
transfer
— Data transfer between Flash EEPROM, RAM, peripheral modules, and I/O ports
Memory
– 512K, 384K, 256K byte Flash EEPROM
– 4K byte EEPROM
– 32K, 28K, 16K byte RAM
CRG (clock and reset generator)
— Low noise/low power Pierce oscillator
— PLL
— COP watchdog
— Real time interrupt
— Clock monitor
— Fast wake-up from stop mode
Analog-to-digital converter
— 16 channels, 10-bit resolution
— External conversion trigger capability
ECT (enhanced capture timer)
— 16-bit main counter with 8-bit prescaler
— 8 programmable input capture or output compare channels
— Four 8-bit or two 16-bit pulse accumulators
PIT (periodic interrupt timer)
— Four timers with independent time-out periods
— Time-out periods selectable between 1 and 224 bus clock cycles
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
•
•
•
•
•
•
•
8 PWM (pulse-width modulator) channels
— Programmable period and duty cycle
— 8-bit 8-channel or 16-bit 4-channel
— Separate control for each pulse width and duty cycle
— Center-aligned or left-aligned outputs
— Programmable clock select logic with a wide range of frequencies
— Fast emergency shutdown input
Two 1-Mbps, CAN 2.0 A, B software compatible modules
— Five receive and three transmit buffers
— Flexible identifier filter programmable as 2 x 32 bit, 4 x 16 bit, or 8 x 8 bit
— Four separate interrupt channels for Rx, Tx, error, and wake-up
— Low-pass filter wake-up function
— Loop-back for self-test operation
Two IIC (Inter-IC bus) Modules
— Compatible with IIC bus standard
— Multi-master operation
— Broadcast mode
Serial interfaces
— Two asynchronous serial communication interfaces (SCI) with additional LIN support and
selectable IrDA 1.4 return-to-zero-inverted (RZI) format with programmable pulse width
— Synchronous Serial Peripheral Interface (SPI)
Liquid crystal display (LCD) driver with variable input voltage
— Configurable for up to 32 frontplanes and 4 backplanes or general-purpose input or output
— 5 modes of operation allow for different display sizes to meet application requirements
— Unused frontplane and backplane pins can be used as general-purpose I/O
PWM motor controller (MC) with 24 high current drivers
— Each PWM channel switchable between two drivers in an H-bridge configuration
— Left, right and center aligned outputs
— Support for sine and cosine drive
— Dithering
— Output slew rate control
Six stepper stall detectors (SSD)
— Full step control during return to zero
— Voltage detector and integrator / sigma delta converter circuit
— 16-bit accumulator register
— 16-bit modulus down counter
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
23
Chapter 1 MC9S12XHZ Family Device Overview
•
•
•
•
1.1.2
On-Chip Voltage Regulator
— Two parallel, linear voltage regulators with bandgap reference
— Low-voltage detect (LVD) with low-voltage interrupt (LVI)
— Power-on reset (POR) circuit
— 3.3-V–5.5-V operation
— Low-voltage reset (LVR)
— Ultra low-power wake-up timer
144-pin LQFP and 112-pin LQFP packages
— I/O lines with 5-V input and drive capability
— Input threshold on external bus interface inputs switchable for 3.3-V or 5-V operation
— 5-V A/D converter inputs
— 8 key wake up interrupts with digital filtering and programmable rising/falling edge trigger
Operation at 80 MHz equivalent to 40-MHz bus speed
Development support
— Single-wire background debug™ mode (BDM)
— Four on-chip hardware breakpoints
Modes of Operation
User modes:
• Normal and emulation operating modes
— Normal single-chip mode
— Normal expanded mode
— Emulation of single-chip mode
— Emulation of expanded mode
• Special Operating Modes
— Special single-chip mode with active background debug mode
— Special test mode (Freescale use only)
Low-power modes:
• System stop modes
— Pseudo stop mode
— Full stop mode
• System wait mode
1.1.3
Block Diagram
Figure 1-1 shows a block diagram of the MC912XHZ family.
MC9S12XHZ512 Data Sheet, Rev. 1.06
24
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
Pins and signals shown in BOLD
are not available in the 112 QFP package
512K, 384K, 256K Bytes Flash EEPROM
4k Bytes EEPROM
VDDR
VDD1
VSS1,2
Enahanced
Capture
Timer
Voltage Regulator
SSD3
SSD4
SSD5
M2C0M
M2C0P
M2C1M
PWM5 M2C1P
M3C0M
PWM6 M3C0P
M3C1M
PWM7 M3C1P
M4C0M
PWM8 M4C0P
M4C1M
PWM9 M4C1P
M5C0M
PWM10 M5C0P
M5C1M
PWM11 M5C1P
DDRAD
PTAD
PWM3
PTU
PWM2
PU0
PU1
PU2
PU3
PU4
PU5
PU6
PU7
PWM4
PTV
FP23
PWM1
M0C0M
M0C0P
M0C1M
M0C1P
M1C0M
M1C0P
M1C1M
M1C1P
DDRV
SSD2
M2COSM
M2COSP
M2SINM
M2SINP
M3COSM
M3COSP
M3SINM
M3SINP
M4COSM
M4COSP
M4SINM
M4SINP
M5COSM
M5COSP
M5SINM
M5SINP
PWM0
PAD0
PAD1
PAD2
PAD3
PAD4
PAD5
PAD6
PAD7
PTW
SSD1
M0COSM
M0COSP
M0SINM
M0SINP
M1COSM
M1COSP
M1SINM
M1SINP
KWAD0
KWAD1
KWAD2
KWAD3
KWAD4
KWAD5
KWAD6
KWAD7
DDRU
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
AN8
AN9
AN10
AN11
AN12
AN13
AN14
AN15
SSD0
VDDA
VSSA
VRH
VRL
VDDA
VSSA
VRH
VRL
Analog to
Digital
Converter
DDRW
FP22
BP0
BP1
BP2
BP3
Enhanced
Multilevel
Interrupt
Module
AN8
AN9
AN10
AN11
AN12
AN13
AN14
AN15
VLCD
A/D Converter &
Voltage Regulator 5V
VDDA
VSSA
PLL Supply 2.5V
VDDPLL
VSSPLL
I/O Supply 5V
VDDX1,2
VSSX1,2
RXCAN1
CAN1 TXCAN1
SCI0
SCI1
SPI
PW0
PW1
Pulse
PW2
Width
Modulator PW3
PW4
PW5
PW6
PW7
Internal 2.5V
VDD1
VSS1,2
Voltage Regulator 5V
VDDR
RXD0
TXD0
RXD1
TXD1
MISO
MOSI
SCK
SS
IIC0
SDA0
SCL0
IIC1
SDA1
SCL1
PTM
DDRM
CAN0 TXCAN0
PTP
FP24
FP25
FP26
FP27
SDA0
SCL0
SDA1
SCL1
Motor Supplies
VDDM1,2,3
VSSM1,2,3
DDRS
PTS
RXCAN0
FP0
FP1
FP2
FP3
FP4
FP5
FP6
FP7
FP8
FP9
FP10
FP11
FP12
FP13
FP14
FP15
PV0
PV1
PV2
PV3
PV4
PV5
PV6
PV7
PW0
PW1
PW2
PW3
PW4
PW5
PW6
PW7
VLCD
DDRP
IOC0
IOC1
IOC2
IOC3
IOC4
IOC5
IOC6
IOC7
Non-Multiplexed External Bus Interface
ADDR0
ADDR1
ADDR2
ADDR3
ADDR4
ADDR5
ADDR6
ADDR7
ADDR8
ADDR9
ADDR10
ADDR11
ADDR12
ADDR13
ADDR14
ADDR15
FP20
FP21
LCD Driver
DDRL
PTL
PTE
DDRE
DDRK
PTK
PTD
DDRD
DDRC
PTC
PTB
XIRQ
IRQ
RW/WE
LSTRB/LDS/EROMCTL
ECLK
MODA/TAGLO/RE
MODB/TAGHI
XCLKS/ECLKX2
ADDR16/IQSTAT0
ADDR17/IQSTAT1
ADDR18/IQSTAT2
ADDR19/IQSTAT3
ADDR20/ACC0
ADDR21/ACC1
ADDR22/ACC2
EWAIT/ROMCTL
DATA0
DATA1
DATA2
DATA3
DATA4
DATA5
DATA6
DATA7
DATA8
DATA9
DATA10
DATA11
DATA12
DATA13
DATA14
DATA15
4-Channel
Programmable
Interrupt Timer (PIT)
for internal timebases
Module-to-Port-Routing
PT0
PT1
PT2
PT3
PT4
PT5
PT6
PT7
COP Watchdog
Clock Monitor
FP16
FP17
FP18
FP19
FP28
FP29
FP30
FP31
DDRB
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PTA
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
XGATE
Peripheral
Co-Processor
Periodic Interrupt
Clock and
Reset
Generation
Module
Breakpoints
DDRA
PE0
PE1
PE2
PE3
PE4
PE5
PE6
PE7
PK0
PK1
PK2
PK3
PK4
PK5
PK6
PK7
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PLL
PTT
XFC
VDDPLL
VSSPLL
EXTAL
XTAL
RESET
PL0
PL1
PL2
PL3
PL4
PL5
PL6
PL7
32K, 28K, 16K Bytes RAM
Single-Wire Background
CPU12X
Debug Module
DDRT
TEST
BKGD
PM1 CS1
PM2
PM3
PM4
PM5
PS0
PS1
PS2 CS3
PS3
PS4
PS5
PS6
PS7
PP0
PP1
PP2
PP3
PP4
PP5
PP6 CS0
PP7 CS2
Figure 1-1. MC9S12XHZ Family Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
25
Chapter 1 MC9S12XHZ Family Device Overview
1.1.4
Device Memory Map
Table 1-1 shows the device memory map for the MC912XHZ family.
Unimplemented register space shown in Table 1-1 is not allocated to any module. Writing to these
locations have no effect. Read access to these locations returns zero.
Table 1-1. Device Register Memory Map
Address
Offset
Module
Size
(Bytes)
0x0000–0x0009
PIM (port integration module)
10
0x000A–0x000B
MMC (memory map control)
2
0x000C–0x000D
PIM (port integration module)
2
0x000E–0x000F
EBI (external bus interface)
2
0x0010–0x0017
MMC (memory map control)
8
0x0018–0x0019
Unimplemented
2
0x001A–0x001B
Device ID register
2
0x001C–0x001F
PIM (port integration module)
4
0x0020–0x002F
DBG (debug module)
16
0x0030–0x0031
MMC (memory map control)
2
0x0032–0x0033
PIM (port integration module)
2
0x0034–0x003F
CRG (clock and reset generator)
12
0x0040–0x007F
ECT (enhanced capture timer 16-bit 8-channel)
64
0x0080–0x00AF
ATD (analog-to-digital converter 10-bit 16-channel)
48
0x00B0–0x00BF
INT (interrupt module)
16
0x00C0–0x00C7
IIC0 (inter IC bus)
8
0x00C8–0x00CF
SCI0 (serial communications interface)
8
0x00D0–0x00D7
SCI1 (serial communications interface)
8
0x00D8–0x00DF
SPI (serial peripheral interface)
8
0x00E0–0x00FF
Unimplemented
32
0x0100–0x010F
Flash control registers
16
0x0110–0x011B
EEPROM control registers
12
0x011C–0x011F
MMC (memory map control)
4
0x0120–0x0137
Liquid Crystal Display Driver 32x4 (LCD)
24
0x0138–0x013F
IIC1 (inter IC bus)
8
0x0140–0x017F
CAN0 (scalable CAN)
64
0x0180–0x01BF
CAN1 (scalable CAN)
64
0x01C0–0x01FF
MC (motor controller)
64
0x0200–0x027F
PIM (port integration module)
128
0x0280–0x0287
SSD4 (stepper stall detector)
8
0x0288–0x028F
SSD0 (stepper stall detector)
8
0x0290–0x0297
SSD1 (stepper stall detector)
8
0x0298–0x029F
SSD2 (stepper stall detector)
8
MC9S12XHZ512 Data Sheet, Rev. 1.06
26
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-1. Device Register Memory Map
Address
Offset
Size
(Bytes)
Module
0x02A0–0x02A7
SSD3 (stepper stall detector)
8
0x02A8–0x02AF
SSD5 (stepper stall detector)
8
0x02B0–0x02EF
Unimplemented
64
0x02F0–0x02F7
Voltage regulator
8
0x02F8–0x02FF
Unimplemented
8
0x0300–0x0327
PWM (pulse-width modulator 8 channels)
40
0x0328–0x033F
Unimplemented
24
0x0340–0x0367
PIT (periodic interrupt timer)
40
0x0368–0x037F
Unimplemented
24
0x0380–0x03BF
XGATE
64
0x03C0–0x03FF
Unimplemented
64
0x0400–0x07FF
Unimplemented
1024
Figure 1-2 shows the CPU & BDM local address translation to the global memory map. It indicates also
the location of the internal resources in the memory map.
Table 1-2. Device Internal Resources
Device
RAMSIZE /
RAM_LOW
EEPROMSIZE /
EEPROM_LOW
FLASHSIZE0 /
FLASH0_LOW
FLASHSIZE1 /
FLASH1_HIGH
MC9S12XHZ512
32K / 0x0F_8000
4K / 0x13_F000
256K / 0x7B_FFFF
256K / 0x7C_0000
MC9S12XHZ384
28K / 0x0F_9000
4K / 0x13_F000
128K / 0x79_FFFF
256K / 0x7C_0000
MC9S12XHZ256
16K / 0x0F_C000
4K / 0x13_F000
128K / 0x79_FFFF
128K / 0x7E_0000
Figure 1-3 shows XGATE local address translation to the global memory map. It indicates also the location
of used internal resources in the memory map.
Table 1-3. XGATE Resources
1
Device
XGRAMSIZE / XGRAMLOW
XGFLASHSIZE / XGFLASH_HIGH
MC9S12XHZ512
32K / 0x0F_8000
30K1 / 0x78_7FFF
MC9S12XHZ384
28K / 0x0F_9000
MC9S12XHZ256
16K / 0x0F_C000
This value is calculated by the following formula: (64K - 2K - XGRAMSIZE)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
27
Chapter 1 MC9S12XHZ Family Device Overview
CPU and BDM
Local Memory Map
Global Memory Map
0x00_0000
0x00_07FF
2K REGISTERS
CS3
Unimplemented
RAM
0x0800
0x0C00
0x1000
RAM
2K REGISTERS
1K EEPROM window
EPAGE
0x0F_FFFF
1K EEPROM
4K RAM window
Unimplemented
EEPROM
RPAGE
CS2
0x0000
RAMSIZE
RAM_LOW
8K RAM
EEPROM_LOW
EEPROM
0x4000
0x13_FFFF
CS2
Unpaged
16K FLASH
EEPROMSIZE
0x2000
0x1F_FFFF
External
Space
CS1
0x8000
PPAGE
0x3F_FFFF
0xC000
CS0
16K FLASH window
Unimplemented
FLASH
0x78_0000
FLASH0
FLASH0_LOW
Unimplemented
FLASH
FLASH1
0x7F_FFFF
FLASHSIZE1
FLASH1_HIGH
CS0
Reset Vectors
FLASHSIZE
0xFFFF
FLASHSIZE0
Unpaged
16K FLASH
Figure 1-2. MC9S12XHZ Family Global Memory Map
MC9S12XHZ512 Data Sheet, Rev. 1.06
28
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
XGATE
Local Memory Map
Global Memory Map
0x00_0000
Registers
0x00_07FF
XGRAM_LOW
0x0800
RAM
0x0F_FFFF
RAMSIZE
Registers
XGRAMSIZE
0x0000
FLASH
RAM
0x78_0800
0xFFFF
FLASHSIZE
FLASH
XGFLASH_HIGH
0x7F_FFFF
Figure 1-3. XGATE Global Address Mapping
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
29
Chapter 1 MC9S12XHZ Family Device Overview
1.1.5
Part ID Assignments
The part ID is located in two 8-bit registers PARTIDH and PARTIDL (addresses 0x001A and 0X001B).
The read-only value is a unique part ID for each revision of the chip. Table 1-4 shows the assigned part ID
number and mask set number.
Table 1-4. Assigned Part ID Numbers
Device
1
Mask Set Number
Part ID
0M80F
1M80F
0xE400
0xE401
MC9S12XHZ512
MC9S12XHZ384
MC9S12XHZ256
1
The coding is as follows:
Bit 15-12: Major family identifier
Bit 11-8: Minor family identifier
Bit 7-4: Major mask set revision including fab transfers
Bit 3-0: Minor non-full mask set revision
1.2
Signal Description
This section describes signals that connect off-chip. It includes a pinout diagram, a table of signal
properties, and detailed discussion of signals.
1.2.1
Device Pinout
The MC912XHZ family is offered in the following package options:
• 144-pin LQFP with an external bus interface (address/data bus)
• 112-pin LQFP without an external bus interface
Figure 1-4 and Figure 1-5 show the pin assignments.
MC9S12XHZ512 Data Sheet, Rev. 1.06
30
Freescale Semiconductor
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
PT7/IOC7/SCL1
PT6/IOC6/SDA1
PT5/IOC5/SCL0
PT4/IOC4/SDA0
PT3/IOC3/FP27
PT2/IOC2/FP26
PT1/IOC1/FP25
PT0/IOC0/FP24
PC7/DATA15
PC6/DATA14
PC5/DATA13
PC4/DATA12
VSSX1
VDDX1
PK7/EWAIT/ROMCTL/FP23
PE7/ECLKX2/XCLKS/FP22
PE3/LSTRB/LDS/EROMCTL/FP21
PE2/RW/WE/FP20
PC3/DATA11
PC2/DATA10
PC1/DATA9
PC0/DATA8
PL3/AN11/FP19
PL2/AN10/FP18
PL1/AN9/FP17
PL0/AN8/FP16
PA7/ADDR15/FP15
PA6/ADDR14/FP14
PA5/ADDR13/FP13
PA4/ADDR12/FP12
PA3/ADDR11/FP11
PA2/ADDR10/FP10
PA1/ADDR9/FP9
PA0/ADDR8/FP8
PB7/ADDR7/FP7
PB6/ADDR6/FP6
Chapter 1 MC9S12XHZ Family Device Overview
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
MC9S12XHZ Family
144 LQFP
Pins shown in BOLD are not available in the 112 QFP package
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
PB5/ADDR5/FP5
PB4/ADDR4/FP4
PB3/ADDR3/FP3
PB2/ADDR2/FP2
PB1/ADDR1/FP1
PB0/ADDR0/FP0
PK0/ADDR16/BP0
PK1/ADDR17/BP1
PK2/ADDR18/BP2
PK3/ADDR19/BP3
VLCD
VSS1
VDD1
PD7/DATA7
PD6/DATA6
PD5/DATA5
PD4/DATA4
PD3/DATA3
PD2/DATA2
PD1/DATA1
PD0/DATA0
PAD7/KWAD7/AN7
PAD6/KWAD6/AN6
PAD5/KWAD5/AN5
PAD4/KWAD4/AN4
PAD3/KWAD3/AN3
PAD2/KWAD2/AN2
PAD1/KWAD1/AN1
PAD0/KWAD0/AN0
VDDA
VRH
VRL
VSSA
PE0/XIRQ
PE4/ECLK
PE6/MODB/TAGHI
PWM3/PP3
RXD1/PWM2/PP2
TXD1/PWM0/PP0
PWM1/PP1
CS0/SDA1/PWM6/PP6
CS2/SCL1/PWM7/PP7
ACC0/ADDR20/PK4
ACC1/ADDR21/PK5
RXD0/PS0
TXD0/PS1
CS3/RXD1/PS2
TXD1/PS3
VSS2
VDDR
VDDX2
VSSX2
MODC/BKGD
RESET
VDDPLL
XFC
VSSPLL
EXTAL
XTAL
TEST
ACC2/ADDR22/PK6
CS1/PM1
RXCAN0/PM2
TXCAN0/PM3
RXCAN1/PM4
TXCAN1/PM5
TAGLO/RE/MODA/PE5
MISO/PS4
MOSI/PS5
SCK/PS6
SS/PS7
IRQ/PE1
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
FP28/AN12/PL4
FP29AN13/PL5
FP30/AN14/PL6
FP31/AN15/PL7
M4C0M/M4COSM/PW0
M4C0P/M4COSP/PW1
M4C1M/M4SINM/PW2
M4C1P/M4SINP/PW3
VDDM1
VSSM1
M0C0M/M0COSM/PU0
M0C0P/M0COSP/PU1
M0C1M/M0SINM/PU2
M0C1P/M0SINP/PU3
M1C0M/M1COSM/PU4
M1C0P/M1COSP/PU5
M1C1M/M1SINM/PU6
M1C1P/M1SINP/PU7
VDDM2
VSSM2
M2C0M/M2COSM/PV0
M2C0P/M2COSP/PV1
M2C1M/M2SINM/PV2
M2C1P/M2SINP/PV3
M3C0M/M3COSM/PV4
M3C0P/M3COSP/PV5
M3C1M/M3SINM/PV6
M3C1P/M3SINP/PV7
VDDM3
VSSM3
M5C0M/M5COSM/PW4
M5C0P/M5COSP/PW5
M5C1M/M5SINM/PW6
M5C1P/M5SINP/PW7
SCL0/PWM5/PP5
SDA0/PWM4/PP4
Figure 1-4. MC9S12XHZ Family 144 LQFP Pin Assignment
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
31
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
PT3/IOC3/FP27
PT2/IOC2/FP26
PT1/IOC1/FP25
PT0/IOC0/FP24
VSSX1
VDDX1
PK7/FP23
PE7/XCLKS/FP22
PE3/FP21
PE2/FP20
PL3/AN11/FP19
PL2/AN10/FP18
PL1/AN9/FP17
PL0/AN8/FP16
PA7/FP15
PA6/FP14
PA5/FP13
PA4/FP12
PA3/FP11
PA2/FP10
PA1/FP9
PA0/FP8
PB7/FP7
PB6/FP6
MC9S12XHZ Family
112 LQFP
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
PB5/FP5
PB4/FP4
PB3/FP3
PB2/FP2
PB1/FP1
PB0/FP0
PK0/BP0
PK1/BP1
PK2/BP2
PK3/BP3
VLCD
VSS1
VDD1
PAD7/KWAD7/AN7
PAD6/KWAD6/AN6
PAD5/KWAD5/AN5
PAD4/KWAD4/AN4
PAD3/KWAD3/AN3
PAD2/KWAD2/AN2
PAD1/KWAD1/AN1
PAD0/KWAD0/AN0
VDDA
VRH
VRL
VSSA
PE0/XIRQ
PE4/ECLK
PE6
PE5
MISO/PS4
MOSI/PS5
SCK/PS6
SS/PS7
IRQ/PE1
RXCAN1/PM4
TXCAN1/PM5
PWM3/PP3
RXD1/PWM2/PP2
TXD1/PWM0/PP0
PWM1/PP1
RXD0/PS0
TXD0/PS1
VSS2
VDDR
VDDX2
VSSX2
MODC/BKGD
RESET
VDDPLL
XFC
VSSPLL
EXTAL
XTAL
TEST
RXCAN0/PM2
TXCAN0/PM3
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
FP28/AN12/PL4
FP29AN13//PL5
FP30/AN14//PL6
FP31/AN15/PL7
VDDM1
VSSM1
M0C0M/M0COSM/PU0
M0C0P/M0COSP/PU1
M0C1M/M0SINM/PU2
M0C1P/M0SINP/PU3
M1C0M/M1COSM/PU4
M1C0P/M1COSP/PU5
M1C1M/M1SINM/PU6
M1C1P/M1SINP/PU7
VDDM2
VSSM2
M2C0M/M2COSM/PV0
M2C0P/M2COSP/PV1
M2C1M/M2SINM/PV2
M2C1P/M2SINP/PV3
M3C0M/M3COSM/PV4
M3C0P/M3COSP/PV5
M3C1M/M3SINM/PV6
M3C1P/M3SINP/PV7
VDDM3
VSSM3
SCL0/PWM5/PP5
SDA0/PWM4/PP4
112
111
110
109
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
PT7/IOC7/SCL1
PT6/IOC6/SDA1
PT5/IOC5/SCL0
PT4/IOC4/SDA0
Chapter 1 MC9S12XHZ Family Device Overview
Figure 1-5. MC9S12XHZ Family 112 LQFP Pin Assignment
MC9S12XHZ512 Data Sheet, Rev. 1.06
32
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.2.2
Signal Properties Summary
Table 1-5 summarizes all pin functions.
Table 1-5. Signal Properties
Pin
Pin
Name
Name
Function 1 Function 2
Pin
Name
Function 3
Pin
Pin
Powered
Name
Name
by
Function 4 Function 5
Internal Pull Up
Resistor
Description
CTRL
Reset
State
EXTAL
—
—
—
—
VDDPLL
NA
NA
NA
NA
Oscillator pins
XTAL
—
—
—
—
VDDPLL
RESET
—
—
—
—
VDDX2
TEST
—
—
—
—
NA
NA
NA
Test input - must be tied to
VSS in all applications
XFC
—
—
—
—
VDDPLL
NA
NA
PLL loop Filter
BKGD
MODC
—
—
—
VDDX2
Always on
Up
Background debug, mode
input
PAD[7:0]
AN[7:0]
KWAD[7:0]
—
—
VDDA
PERAD/
PPSAD
PA[7:0]
FP[15:8]
ADDR[15:8]
IVD[15:8]
—
VDDX1
PUCR
Down
Port A I/O, address bus,
internal visibility data
PB[7:1]
FP[7:1]
ADDR[7:1]
IVD[7:1]
—
VDDX1
PUCR
Down
Port B I/O, address bus,
internal visibility data
PB0
FP0
ADDR0
IVD0
UDS
VDDX1
PUCR
Down
Port B I/O, address bus,
internal visibility data,
upper data strobe
PC[7:0]
—
DATA[15:8]
—
—
VDDX1
PUCR
Disabled Port C I/O, data bus
PD[7:0]
—
DATA[7:0]
—
—
VDDX1
PUCR
Disabled Port D I/O, data bus
PE7
FP22
ECLKX2
XCLKS
—
VDDX1
PUCR
PE6
TAGHI
MODB
—
—
VDDX2
While RESET
pin is low: Down
Port E I/O, tag high, mode
input
PE5
TAGLO
MODA
RE
—
VDDX2
While RESET
pin is low: Down
Port E I/O, tag low, mode input,
read enable
PE4
ECLK
—
—
—
VDDX2
PUCR
Down
Port E I/O, bus clock output
PE3
FP21
LSTRB
LDS
EROMCTL
VDDX1
PUCR
Down
Port E I/O, LCD driver, low byte
strobe, EROMON control
PE2
FP20
R/W
WE
—
VDDX1
PUCR
Down
Port E I/O, read/write, write
enable
PE1
IRQ
—
—
—
VDDX2
PUCR
PE0
XIRQ
—
—
—
VDDX2
PUCR
PULL UP
External reset
Disabled Port AD I/O, Analog inputs
(ATD), interrupts
Down
Port E I/O, LCD driver,
system clock output,
clock select
Up
Port E input, maskable
interrupt
Up
Port E input, non-maskable
interrupt
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
33
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-5. Signal Properties
Pin
Pin
Name
Name
Function 1 Function 2
Pin
Name
Function 3
Pin
Pin
Powered
Name
Name
by
Function 4 Function 5
Internal Pull Up
Resistor
Description
CTRL
Reset
State
PUCR
Down
PK7
FP23
ECS
ROMCTL
ROMCTL
VDDX1
PK[6:4]
—
ADDR[22:20]
ACC[2:0]
—
VDDX2
Port K I/O, extended address,
access source
PK[3:0]
BP[3:0]
—
VDDX1
Port K I/O, LCD driver,
extended address, pipe status
PL[7:4]
FP[31:28]
AN[15:12]
—
—
VDDA
PL[3:0]
FP[19:16]
AN[11:8]
—
—
VDDX1
PM5
TXCAN1
—
—
—
VDDX2
PM4
RXCAN1
—
—
—
VDDX2
PM3
TXCAN0
—
—
—
VDDX2
Port M I/O, TX of CAN0
PM2
RXCAN0
—
—
—
VDDX2
Port M I/O, RX of CAN0
ADDR[19:16] IQSTAT[3:0]
PERL/
PPSL
Down
Port K I/O, emulation chip
select, ROM on enable
Port L I/O, LCD drivers, analog
inputs (ATD)
Port L I/O, LCD drivers, analog
inputs (ATD)
PERM/
PPSM
Disabled Port M I/O, TX of CAN1
Port M I/O, RX of CAN1
PM1
—
—
CS1
—
VDDX2
PP7
PWM7
SCL1
CS2
—
VDDX2
PP6
PWM6
SDA1
CS0
—
VDDX2
Port P I/O, PWM channel, SDA
of IIC1, chip select 0
PP5
PWM5
SCL0
—
—
VDDX2
Port P I/O, PWM channel,
SCL of IIC0
PP4
PWM4
SDA0
—
—
VDDX2
Port P I/O, PWM channel,
SDA of IIC0
PP3
PWM3
—
—
—
VDDX2
Port P I/O, PWM channel
PP2
PWM2
RXD1
—
—
VDDX2
Port P I/O, PWM channel,
RXD of SCI1
PP1
PWM1
—
—
—
VDDX2
Port P I/O, PWM channel
PP0
PWM0
TXD1
—
—
VDDX2
Port P I/O, PWM channel, TXD
of SCI1
Port M I/O, chip select 1
PERP/
PPSP
Disabled Port P I/O, PWM channel,
SCL of IIC1, chip select 2
PS7
SS
—
—
—
VDDX2
PS6
SCK
—
—
—
VDDX2
PS5
MOSI
—
—
—
VDDX2
Port S I/O, MOSI of SPI
PS4
MISO
—
—
—
VDDX2
Port S I/O, MISO of SPI
PS3
TXD1
—
—
—
VDDX2
Port S I/O, TXD of SCI1
PS2
RXD1
—
CS3
—
VDDX2
Port S I/O, RXD of SCI1, chip
select 3
PS1
TXD0
—
—
—
VDDX2
Port S I/O, TXD of SCI0
PS0
RXD0
—
—
—
VDDX2
Port S I/O, RXD of SCI0
PERS/
PPSS
Disabled Port S I/O, SS of SPI
Port S I/O, SCK of SPI
MC9S12XHZ512 Data Sheet, Rev. 1.06
34
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-5. Signal Properties
Pin
Pin
Name
Name
Function 1 Function 2
Pin
Name
Function 3
Pin
Pin
Powered
Name
Name
by
Function 4 Function 5
Internal Pull Up
Resistor
Description
CTRL
Reset
State
PT7
IOC7
SCL1
—
—
VDDX1
PT6
IOC6
SDA1
—
—
VDDX1
Port T I/O, Timer channels,
SDA of IIC1
PT5
IOC5
SCL0
—
—
VDDX1
Port T I/O, Timer channels,
SCL of IIC0
PT4
IOC4
SDA0
—
—
VDDX1
Port T I/O, Timer channels,
SDA of IIC0
PT[3:0]
IOC[3:0]
FP[27:24]
—
—
VDDX1
PERT/
PPST
PU7
M1C1P
M1SINP
—
—
VDDM1,2,3
PERU/
PPSU
PU6
M1C1M
M1SINM
—
—
VDDM1,2,3
PU5
M1C0P
M1COSP
—
—
VDDM1,2,3
PU4
M1C0M
M1COSM
—
—
VDDM1,2,3
PU3
M0C1P
M0SINP
—
—
VDDM1,2,3
PU2
M0C1M
M0SINM
—
—
VDDM1,2,3
PU1
M0C0P
M0COSP
—
—
VDDM1,2,3
PU0
M0C0M
M0COSM
—
—
VDDM1,2,3
PV7
M3C1P
M3SINP
—
—
VDDM1,2,3
PV6
M3C1M
M3SINM
—
—
VDDM1,2,3
PV5
M3C0P
M3COSP
—
—
VDDM1,2,3
PV4
M3C0M
M3COSM
—
—
VDDM1,2,3
PV3
M2C1P
M2SINP
—
—
VDDM1,2,3
PV2
M2C1M
M2SINM
—
—
VDDM1,2,3
PV1
M2C0P
M2COSP
—
—
VDDM1,2,3
PV0
M2C0M
M2COSM
—
—
VDDM1,2,3
PW7
M5C1P
M5SINP
—
—
VDDM1,2,3
PW6
M5C1M
M5SINM
—
—
VDDM1,2,3
PW5
M5C0P
M5COSP
—
—
VDDM1,2,3
PW4
M5C0M
M5COSM
—
—
VDDM1,2,3
PW3
M4C1P
M4SINP
—
—
VDDM1,2,3
PW2
M4C1M
M4SINM
—
—
VDDM1,2,3
PW1
M4C0P
M4COSP
—
—
VDDM1,2,3
PW0
M4C0M
M4COSM
—
—
VDDM1,2,3
PERT/
PPST
Disabled Port T I/O, Timer channels,
SCL of IIC1
Down
Port T I/O, Timer channels,
LCD driver
Disabled Port U I/O, motor1 coil nodes
of MC or SSD1
Port U I/O, motor 0 coil nodes
of MC or SSD0
PERV/
PPSV
Disabled Port V I/O, motor 3 coil nodes
of MC or SSD3
Port V I/O, motor 2 coil nodes
of MC or SSD2
PERW/
PPSW
Disabled Port W I/O, motor 5 coil nodes
of MC or SSD5
Port W I/O, motor 4 coil nodes
of MC or SSD4
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
35
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-6. Power and Ground
Mnemonic
Nominal
Voltage
VLCD
5.0 V
Voltage reference pin for the LCD driver.
VDD1
2.5 V
VSS1
VSS2
0V
Internal power and ground generated by internal regulator. These also allow an external source
to supply the core VDD/VSS voltages and bypass the internal voltage regulator.
VDDR
5.0 V
VSSR
0V
VDDX1
VDDX2
5.0 V
VSSX1
VSSX2
0V
VDDA
5.0 V
VSSA
0V
VRH
5.0 V
Reference voltage high for the ATD converter.
VRL
0V
Reference voltage low for the ATD converter.
VDDPLL
2.5 V
VSSPLL
0V
VDDM1,2,3
5.0 V
VSSM1,2,3
0V
Description
External power and ground, supply to pin drivers and internal voltage regulator.
External power and ground, supply to pin drivers.
Operating voltage and ground for the analog-to-digital converter and the reference for the internal
voltage regulator, allows the supply voltage to the A/D to be bypassed independently.
Provides operating voltage and ground for the phased-locked Loop. This allows the supply
voltage to the PLL to be bypassed independently. Internal power and ground generated by
internal regulator.
Provides operating voltage and ground for motor 0, 1, 2 and 3.
NOTE
All VSS pins must be connected together in the application. Because fast
signal transitions place high, short-duration current demands on the power
supply, use bypass capacitors with high-frequency characteristics and place
them as close to the MCU as possible. Bypass requirements depend on
MCU pin load.
1.2.3
1.2.3.1
Detailed Signal Descriptions
EXTAL, XTAL — Oscillator Pins
EXTAL and XTAL are the crystal driver and external clock pins. On reset all the device clocks are derived
from the EXTAL input frequency. XTAL is the crystal output.
1.2.3.2
RESET — External Reset Pin
The RESET pin is an active low bidirectional control signal. It acts as an input to initialize the MCU to a
known start-up state, and an output when an internal MCU function causes a reset.The RESET pin has an
internal pullup device.
MC9S12XHZ512 Data Sheet, Rev. 1.06
36
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.3
TEST — Test Pin
This input only pin is reserved for test. This pin has a pulldown device.
NOTE
The TEST pin must be tied to VSS in all applications.
1.2.3.4
XFC — PLL Loop Filter Pin
Please ask your Freescale representative for the interactive application note to compute PLL loop filter
elements. Any current leakage on this pin must be avoided.
VDDPLL
VDDPLL
CS
MCU
R0
CP
XFC
Figure 1-6. PLL Loop Filter Connections
1.2.3.5
BKGD / MODC — Background Debug and Mode Pin
The BKGD/MODC pin is used as a pseudo-open-drain pin for the background debug communication. It
is used as a MCU operating mode select pin during reset. The state of this pin is latched to the MODC bit
at the rising edge of RESET. The BKGD pin has a pullup device.
1.2.3.6
PAD[7:0] / AN[7:0] / KWAD[7:0] — Port AD I/O Pins [7:0]
PAD7–PAD0 are general-purpose input or output pins and analog inputs for the analog-to-digital
converter. They can be configured to generate an interrupt causing the MCU to exit STOP or WAIT mode.
1.2.3.7
PA[7:0] / ADDR[15:8] / IVD[15:8] — Port A I/O Pins
PA[7:0] are general-purpose input or output pins. In MCU expanded modes of operation, these pins are
used for the external address bus. In MCU emulation modes of operation, these pins are used for external
address bus and internal visibility read data.
1.2.3.8
PB[7:1] / ADDR[7:1] / IVD[7:1] — Port B I/O Pins
PB[7:1] are general-purpose input or output pins. In MCU expanded modes of operation, these pins are
used for the external address bus. In MCU emulation modes of operation, these pins are used for external
address bus and internal visibility read data.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
37
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.9
PB0 / ADDR0 / UDS / IVD[0] — Port B I/O Pin 0
PB0 is a general-purpose input or output pin. In MCU expanded modes of operation, this pin is used for
the external address bus ADDR0 or as upper data strobe signal. In MCU emulation modes of operation,
this pin is used for external address bus ADDR0 and internal visibility read data IVD0.
1.2.3.10
PC[7:0] / DATA [15:8] — Port C I/O Pins
PC[7:0] are general-purpose input or output pins. In MCU expanded modes of operation, these pins are
used for the external data bus.
The input voltage thresholds for PC[7:0] can be configured to reduced levels, to allow data from an external
3.3-V peripheral to be read by the MCU operating at 5.0 V. The input voltage thresholds for PC[7:0] are
configured to reduced levels out of reset in expanded and emulation modes. The input voltage thresholds
for PC[7:0] are configured to 5-V levels out of reset in normal modes.
1.2.3.11
PD[7:0] / DATA [7:0] — Port D I/O Pins
PD[7:0] are general-purpose input or output pins. In MCU expanded modes of operation, these pins are
used for the external data bus.
The input voltage thresholds for PD[7:0] can be configured to reduced levels, to allow data from an
external 3.3-V peripheral to be read by the MCU operating at 5.0 V. The input voltage thresholds for
PD[7:0] are configured to reduced levels out of reset in expanded and emulation modes. The input voltage
thresholds for PC[7:0] are configured to 5-V levels out of reset in normal modes.
1.2.3.12
PE7 / FP22 / ECLKX2 / XCLKS — Port E I/O Pin 7
PE7 is a general-purpose input or output pin. The pin can be configured as frontplane segment driver output
FP22 of the LCD module or as the internal system clock ECLKX2.
The XCLKS is an input signal which controls whether a crystal in combination with the internal loop
controlled (low power) Pierce oscillator is used or whether full swing Pierce oscillator/external clock
circuitry is used.
The XCLKS signal selects the oscillator configuration during reset low phase while a clock quality check
is ongoing. This is the case for:
• Power on reset or low-voltage reset
• Clock monitor reset
• Any reset while in self-clock mode or full stop mode
The selected oscillator configuration is frozen with the rising edge of reset.
MC9S12XHZ512 Data Sheet, Rev. 1.06
38
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
EXTAL
C1
MCU
Crystal or
Ceramic Resonator
XTAL
C2
VSSPLL
Figure 1-7. Loop Controlled Pierce Oscillator Connections (PE7 = 0)
EXTAL
C1
MCU
RB
RS
Crystal or
Ceramic Resonator
XTAL
C2
VSSPLL
Figure 1-8. Full Swing Pierce Oscillator Connections (PE7 = 1)
EXTAL
CMOS-Compatible
External Oscillator
MCU
XTAL
Not Connected
Figure 1-9. External Clock Connections (PE7 = 1)
1.2.3.13
PE6 / MODB / TAGHI — Port E I/O Pin 6
PE6 is a general-purpose input or output pin. It is used as a MCU operating mode select pin during reset.
The state of this pin is latched to the MODB bit at the rising edge of RESET. This pin is an input with a
pull-down device which is only active when RESET is low. TAGHI is used to tag the high half of the
instruction word being read into the instruction queue.
The input voltage threshold for PE6 can be configured to reduced levels, to allow data from an external
3.3-V peripheral to be read by the MCU operating at 5.0 V. The input voltage threshold for PE6 is
configured to reduced levels out of reset in expanded and emulation modes.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
39
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.14
PE5 / MODA / TAGLO / RE — Port E I/O Pin 5
PE5 is a general-purpose input or output pin. It is used as a MCU operating mode select pin during reset.
The state of this pin is latched to the MODA bit at the rising edge of RESET. This pin is shared with the
read enable RE output. This pin is an input with a pull-down device which is only active when RESET is
low. TAGLO is used to tag the low half of the instruction word being read into the instruction queue.
The input voltage threshold for PE5 can be configured to reduced levels, to allow data from an external
3.3-V peripheral to be read by the MCU operating at 5.0 V. The input voltage threshold for PE5 is
configured to reduced levels out of reset in expanded and emulation modes.
1.2.3.15
PE4 / ECLK — Port E I/O Pin 4
PE4 is a general-purpose input or output pin. It can be configured to drive the internal bus clock ECLK.
ECLK can be used as a timing reference.
1.2.3.16
PE3 / FP21 / LSTRB / LDS / EROMCTL— Port E I/O Pin 3
PE3 is a general-purpose input or output pin. It can be configured as frontplane segment driver output FP21
of the LCD module. In MCU expanded modes of operation, LSTRB or LDS can be used for the low byte
strobe function to indicate the type of bus access. At the rising edge of RESET the state of this pin is
latched to the EROMON bit.
1.2.3.17
PE2 / FP20 / R/W / WE— Port E I/O Pin 2
PE2 is a general-purpose input or output pin. It can be configured as frontplane segment driver output FP20
of the LCD module. In MCU expanded modes of operations, this pin drives the read/write output signal or
write enable output signal for the external bus. It indicates the direction of data on the external bus.
1.2.3.18
PE1 / IRQ — Port E Input Pin 1
PE1 is a general-purpose input pin and the maskable interrupt request input that provides a means of
applying asynchronous interrupt requests. This will wake up the MCU from stop or wait mode.
1.2.3.19
PE0 / XIRQ — Port E Input Pin 0
PE0 is a general-purpose input pin and the non-maskable interrupt request input that provides a means of
applying asynchronous interrupt requests. This will wake up the MCU from stop or wait mode.
1.2.3.20
PK7 / FP23 / EWAIT / ROMCTL — Port K I/O Pin 7
PK7 is a general-purpose input or output pin. It can be configured as frontplane segment driver output
FP23 of the LCD module. During MCU emulation modes and normal expanded modes of operation, this
pin is used to enable the Flash EEPROM memory in the memory map (ROMCTL). At the rising edge of
RESET, the state of this pin is latched to the ROMON bit. The EWAIT input signal maintains the external
bus access until the external device is ready to capture data (write) or provide data (read).
MC9S12XHZ512 Data Sheet, Rev. 1.06
40
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
The input voltage threshold for PK7 can be configured to reduced levels, to allow data from an external
3.3-V peripheral to be read by the MCU operating at 5.0 V. The input voltage threshold for PK7 is
configured to reduced levels out of reset in expanded and emulation modes.
1.2.3.21
PK[6:4] / ADDR[22:20] / ACC[2:0] — Port K I/O Pin [6:4]
PK[6:4] are general-purpose input or output pins. During MCU expanded modes of operation, the
ACC[2:0] signals are used to indicate the access source of the bus cycle. This pins also provide the
expanded addresses ADDR[22:20] for the external bus. In Emulation modes ACC[2:0] is available and is
time multiplexed with the high addresses
1.2.3.22
PK[3:0] / BP[3:0] / ADDR[19:16] / IQSTAT[3:0] — Port K I/O Pins [3:0]
PK3-PK0 are general-purpose input or output pins. The pins can be configured as backplane segment
driver outputs BP3–BP0 of the LCD module. In MCU expanded modes of operation, these pins provide
the expanded address ADDR[19:16] for the external bus and carry instruction pipe information.
1.2.3.23
PL[7:4] / FP[31:28] / AN[15:12] — Port L I/O Pins [7:4]
PL7–PL4 are general-purpose input or output pins. They can be configured as frontplane segment driver
outputs FP31–FP28 of the LCD module or analog inputs for the analog-to-digital converter.
1.2.3.24
PL[3:0] / FP[19:16] / AN[11:8] — Port L I/O Pins [3:0]
PL3–PL0 are general-purpose input or output pins. They can be configured as frontplane segment driver
outputs FP19–FP16 of the LCD module or analog inputs for the analog-to-digital converter.
1.2.3.25
PM5 / TXCAN1 — Port M I/O Pin 5
PM5 is a general-purpose input or output pin. It can be configured as the transmit pin TXCAN1 of the
scalable controller area network controller 1 (CAN1)
1.2.3.26
PM4 / RXCAN1 — Port M I/O Pin 4
PM4 is a general-purpose input or output pin. It can be configured as the receive pin RXCAN1 of the
scalable controller area network controller 1 (CAN1)
1.2.3.27
PM3 / TXCAN0 — Port M I/O Pin 3
PM3 is a general-purpose input or output pin. It can be configured as the transmit pin TXCAN0 of the
scalable controller area network controller 0 (CAN0)
1.2.3.28
PM2 / RXCAN0 — Port M I/O Pin 2
PM2 is a general-purpose input or output pin. It can be configured as the receive pin RXCAN0 of the
scalable controller area network controller 0 (CAN0).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
41
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.29
PM1 / CS1 — Port M I/O Pin 1
PM1 is a general-purpose input or output pin. It can be configured to provide a chip-select output.
1.2.3.30
PP7 / PWM7 / SCL1 / CS2 — Port P I/O Pin 7
PP7 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM7 or the serial clock pin SCL1 of the inter-IC bus interface 1 (IIC1). It can be
configured to provide a chip-select output.
1.2.3.31
PP6 / PWM6 / SDA1 / CS0 — Port P I/O Pin 6
PP6 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM6 or the serial data pin SDA1 of the inter-IC bus interface 1 (IIC1). It can be
configured to provide a chip-select output.
1.2.3.32
PP5 / PWM5 / SCL0 — Port P I/O Pin 5
PP5 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM5 or the serial clock pin SCL0 of the inter-IC bus interface 0 (IIC0).
1.2.3.33
PP4 / PWM4 / SDA0 — Port P I/O Pin 4
PP4 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM4 or the serial data pin SDA0 of the inter-IC bus interface 0 (IIC0).
1.2.3.34
PP3 / PWM3 — Port P I/O Pin 3
PP3 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM3.
1.2.3.35
PP2 / PWM2 / RXD1 — Port P I/O Pin 2
PP2 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM2 or the receive pin RXD1 of the serial communication interface 1 (SCI1).
1.2.3.36
PP1 / PWM1 — Port P I/O Pin 1
PP1 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM1.
1.2.3.37
PP0 / PWM0 / TXD1 — Port P I/O Pin 0
PP0 is a general-purpose input or output pin. It can be configured as pulse width modulator (PWM)
channel output PWM0 or the transmit pin TXD1 of the serial communication interface 1 (SCI1).
MC9S12XHZ512 Data Sheet, Rev. 1.06
42
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.38
PS7 / SS — Port S I/O Pin 7
PS7 is a general-purpose input or output pin. It can be configured as slave select pin SS of the serial
peripheral interface (SPI).
1.2.3.39
PS6 / SCK — Port S I/O Pin 6
PS6 is a general-purpose input or output pin. It can be configured as serial clock pin SCK of the serial
peripheral interface (SPI).
1.2.3.40
PS5 / MOSI — Port S I/O Pin 5
PS5 is a general-purpose input or output pin. It can be configured as the master output (during master
mode) or slave input (during slave mode) pin MOSI of the serial peripheral interface (SPI).
1.2.3.41
PS4 / MISO — Port S I/O Pin 4
PS4 is a general-purpose input or output pin. It can be configured as master input (during master mode) or
slave output (during slave mode) pin MISO for the serial peripheral interface (SPI).
1.2.3.42
PS3 / TXD1 — Port S I/O Pin 3
PS3 is a general-purpose input or output pin. It can be configured as transmit pin TXD1 of the serial
communication interface 1 (SCI1).
1.2.3.43
PS2 / RXD1 / CS2 — Port S I/O Pin 2
PS2 is a general-purpose input or output pin. It can be configured as receive pin RXD1 of the serial
communication interface 1 (SCI1). It can be configured to provide a chip-select output.
1.2.3.44
PS1 / TXD0 — Port S I/O Pin 1
PS1 is a general-purpose input or output pin. It can be configured as transmit pin TXD0 of the serial
communication interface 0 (SCI0).
1.2.3.45
PS0 / RXD0 — Port S I/O Pin 0
PS0 is a general-purpose input or output pin. It can be configured as receive pin RXD0 of the serial
communication interface 0 (SCI0).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
43
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.46
PT7 / IOC7 / SCL1 — Port T I/O Pin 7
PT7 is a general-purpose input or output pin. It can be configured as input capture or output compare pin
IOC7 of the enhanced capture timer (ECT) or the serial clock pin SCL1 of the inter-IC bus interface 1
(IIC1).
1.2.3.47
PT6 / IOC6 / SDA1 — Port T I/O Pin 6
PT6 is a general-purpose input or output pin. It can be configured as input capture or output compare pin
IOC6 of the enhanced capture timer (ECT) or the serial data pin SDA1 of the inter-IC bus interface 1
(IIC1).
1.2.3.48
PT5 / IOC5 / SCL0 — Port T I/O Pin 5
PT5 is a general-purpose input or output pin. It can be configured as input capture or output compare pin
IOC5 of the enhanced capture timer (ECT) or the serial clock pin SCL0 of the inter-IC bus interface 0
(IIC0).
1.2.3.49
PT4 / IOC4 / SDA0 — Port T I/O Pin 4
PT4 is a general-purpose input or output pin. It can be configured as input capture or output compare pin
IOC4 of the enhanced capture timer (ECT) or the serial data pin SDA0 of the inter-IC bus interface 0
(IIC0).
1.2.3.50
PT[3:0] / IOC[3:0] / FP[27:24] — Port T I/O Pins [3:0]
PT3–PT0 are general-purpose input or output pins. They can be configured as input capture or output
compare pins IOC3–IOC0 of the enhanced capture timer (ECT). They can be configured as frontplane
segment driver outputs FP27–FP24 of the LCD module.
1.2.3.51
PU[7:4] / M1C1(SIN)P, M1C1(SIN)M, M1C0(COS)P, M1C0(COS)M — Port U
I/O Pins [7:4]
PU7–PU4 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 1.
1.2.3.52
PU[3:0] / M0C1(SIN)P, M0C1(SIN)M, M0C0(COS)P, M0C0(COS)M — Port U
I/O Pins [3:0]
PU3–PU0 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 0.
MC9S12XHZ512 Data Sheet, Rev. 1.06
44
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.2.3.53
PV[7:4] / M3C1(SIN)P, M3C1(SIN)M, M3C0(COS)P, M3C0(COS)M — Port V
I/O Pins [7:4]
PV7–PV4 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 3.
1.2.3.54
PV[3:0] / M2C1(SIN)P, M2C1(SIN)M, M2C0(COS)P, M2C0(COS)M — Port V
I/O Pins [3:0]
PV3–PV0 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 2.
1.2.3.55
PW[7:4] / M5C1(SIN)P, M5C1(SIN)M, M5C0(COS)P, M5C0(COS)M — Port
W I/O Pins [7:4]
PW7–PW4 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 5.
1.2.3.56
PW[3:0] / M4C1(SIN)P, M4C1(SIN)M, M4C0(COS)P, M4C0(COS)M — Port
W I/O Pins [3:0]
PW3–PW0 are general-purpose input or output pins. They can be configured as high current PWM output
pins which can be used for motor drive or to measure the back EMF to calibrate the pointer reset position.
These pins interface to the coils of motor 4.
1.2.4
Power Supply Pins
Power and ground pins are described below.
NOTE
All VSS pins must be connected together in the application.
1.2.4.1
VDDR — External Power Pin
VDDR is the power supply pin for the internal voltage regulator.
1.2.4.2
VDDX1, VDDX2, VSSX1, VSSX2 — External Power and Ground Pins
External power and ground for I/O drivers. Because fast signal transitions place high, short-duration
current demands on the power supply, use bypass capacitors with high-frequency characteristics and place
them as close to the MCU as possible. Bypass requirements depend on how heavily the MCU pins are
loaded.
VDDX1 and VDDX2 as well as VSSX1 and VSSX2 are not internally connected.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
45
Chapter 1 MC9S12XHZ Family Device Overview
1.2.4.3
VDD1, VSS1, VSS2 — Internal Logic Power Pins
Power is supplied to the MCU through VDD and VSS. Because fast signal transitions place high,
short-duration current demands on the power supply, use bypass capacitors with high-frequency
characteristics and place them as close to the MCU as possible. This 2.5-V supply is derived from the
internal voltage regulator. There is no static load on those pins allowed.
VSS1 and VSS2 are internally connected.
1.2.4.4
VDDA, VSSA — Power Supply Pins for ATD and VREG
VDDA, VSSA are the power supply and ground pins for the voltage regulator and the analog-to-digital
converter.
1.2.4.5
VRH, VRL — ATD Reference Voltage Input Pins
VRH and VRL are the voltage reference pins for the analog-to-digital converter.
1.2.4.6
VDDPLL, VSSPLL — Power Supply Pins for PLL
Provides operating voltage and ground for the oscillator and the phased-locked loop. This allows the
supply voltage to the oscillator and PLL to be bypassed independently. This 2.5-V voltage is generated by
the internal voltage regulator.
1.2.4.7
VDDM1, VDDM2, VDDM3 — Power Supply Pins for Motor 0 to 3
VDDM1, VDDM2 and VDDM3 are the supply pins for the ports U, V and W. VDDM1, VDDM2 and VDDM3
are internally connected.
1.2.4.8
VSSM1, VSSM2, VSSM3 — Ground Pins for Motor 0 to 3
VSSM1, VSSM2 and VSSM3 are the ground pins for the ports U, V and W. VSSM1, VSSM2 and VSSM3 are
internally connected.
1.2.4.9
VLCD — Power Supply Reference Pin for LCD driver
VLCD is the voltage reference pin for the LCD driver. Adjusting the voltage on this pin will change the
display contrast.
MC9S12XHZ512 Data Sheet, Rev. 1.06
46
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.3
System Clock Description
The clock and reset generator module (CRG) provides the internal clock signals for the core and all
peripheral modules. Figure 1-10 shows the clock connections from the CRG to all modules.
Consult the CRG block description chapter for details on clock generation.
SSD0 . . SSD5
CAN0 & CAN1
MC
LCD
IIC0 & IIC1
SCI0 & SCI1
SPI
Bus Clock
PIT
EXTAL
ECT
CRG
Oscillator Clock
PIM
XTAL
Core Clock
RAM
S12X
XGATE
FLASH
EEPROM
Figure 1-10. Clock Connections
The MCU’s system clock can be supplied in several ways enabling a range of system operating frequencies
to be supported:
• The on-chip phase locked loop (PLL)
• the PLL self clocking
• the oscillator
The clock generated by the PLL or oscillator provides the main system clock frequencies core clock and
bus clock. As shown in Figure 1-10, this system clocks are used throughout the MCU to drive the core, the
memories, and the peripherals.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
47
Chapter 1 MC9S12XHZ Family Device Overview
The program Flash memory and the EEPROM are supplied by the bus clock and the oscillator clock.The
oscillator clock is used as a time base to derive the program and erase times for the NVM’s. Consult the
FTX512k4 and EETX4K block description chapters for more details on the operation of the NVM’s.
The CAN modules may be configured to have their clock sources derived either from the bus clock or
directly from the oscillator clock. This allows the user to select its clock based on the required jitter
performance. Consult MSCAN block description for more details on the operation and configuration of
the CAN blocks.
In order to ensure the presence of the clock the MCU includes an on-chip clock monitor connected to the
output of the oscillator. The clock monitor can be configured to invoke the PLL self-clocking mode or to
generate a system reset if it is allowed to time out as a result of no oscillator clock being present.
In addition to the clock monitor, the MCU also provides a clock quality checker which performs a more
accurate check of the clock. The clock quality checker counts a predetermined number of clock edges
within a defined time window to insure that the clock is running. The checker can be invoked following
specific events such as on wake-up or clock monitor failure.
1.4
Chip Configuration Summary
The MCU can operate in six different modes. The different modes, the state of ROMCTL and EROMCTL
signal on rising edge of RESET, and the security state of the MCU affects the following device
characteristics:
• External bus interface configuration
• Flash in memory map, or not
• Debug features enabled or disabled
The operating mode out of reset is determined by the states of the MODC, MODB, and MODA signals
during reset (see Table 1-7). The MODC, MODB, and MODA bits in the MODE register show the current
operating mode and provide limited mode switching during operation. The states of the MODC, MODB,
and MODA signals are latched into these bits on the rising edge of RESET.
In normal expanded mode and in emulation modes the ROMON bit and the EROMON bit in the
MMCCTL1 register defines if the on chip flash memory is the memory map, or not. (See Table 1-7.) For
a detailed description of the ROMON and EROMON bits refer to the S12X_MMC Bblock description
chapter.
The state of the ROMCTL signal is latched into the ROMON bit in the MMCCTL1 register on the rising
edge of RESET. The state of the EROMCTL signal is latched into the EROMON bit in the MISC register
on the rising edge of RESET.
MC9S12XHZ512 Data Sheet, Rev. 1.06
48
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-7. Chip Modes and Data Sources
BKGD =
MODC
PE6 =
MODB
PE5 =
MODA
PK7 =
ROMCTL
PE3 =
EROMCTL
Normal single chip
1
0
0
X
X
Internal
Special single chip
0
0
0
Emulation single chip
0
0
1
X
0
Emulation memory
X
1
Internal Flash
Chip Modes
Normal expanded
1
Emulation expanded
0
Special test
1
0
1
0
1
1
1
0
Data Source1
0
X
External application
1
X
Internal Flash
0
X
External application
1
0
Emulation memory
1
1
Internal Flash
0
X
External application
1
X
Internal Flash
Internal means resources inside the MCU are read/written.
Internal Flash means Flash resources inside the MCU are read/written.
Emulation memory means resources inside the emulator are read/written (PRU registers, Flash replacement, RAM, EEPROM,
and register space are always considered internal).
External application means resources residing outside the MCU are read/written.
The configuration of the oscillator can be selected using the XCLKS signal (see Table 1-8). For a detailed
description please refer to the CRG block description chapter.
Table 1-8. Clock Selection Based on PE7
PE7 = XCLKS
1.5
1.5.1
1.5.1.1
Description
0
Loop controlled Pierce oscillator selected
1
Full swing Pierce oscillator or external clock source selected
Modes of Operation
User Modes
Normal Expanded Mode
Ports K, A, and B are configured as a 23-bit address bus, ports C and D are configured as a 16-bit data bus,
and port E provides bus control and status signals. This mode allows 16-bit external memory and
peripheral devices to be interfaced to the system. The fastest external bus rate is divide by 2 from the
internal bus rate.
1.5.1.2
Normal Single-Chip Mode
There is no external bus in this mode. The processor program is executed from internal memory. Ports A,
B,C,D, K, and most pins of port E are available as general-purpose I/O.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
49
Chapter 1 MC9S12XHZ Family Device Overview
1.5.1.3
Special Single-Chip Mode
This mode is used for debugging single-chip operation, boot-strapping, or security related operations. The
background debug module BDM is active in this mode. The CPU executes a monitor program located in
an on-chip ROM. BDM firmware is waiting for additional serial commands through the BKGD pin. There
is no external bus after reset in this mode.
1.5.1.4
Emulation of Expanded Mode
Developers use this mode for emulation systems in which the users target application is normal expanded
mode. Code is executed from external memory or from internal memory depending on the state of
ROMON and EROMON bit. In this mode the internal operation is visible on external bus interface.
1.5.1.5
Emulation of Single-Chip Mode
Developers use this mode for emulation systems in which the user’s target application is normal
single-chip mode. Code is executed from external memory or from internal memory depending on the state
of ROMON and EROMON bit. In this mode the internal operation is visible on external bus interface.
1.5.1.6
Special Test Mode
Freescale internal use only.
1.5.2
Low-Power Modes
The microcontroller features two main low-power modes. Consult the respective block description chapter
for information on the module behavior in system stop, system pseudo stop, and system wait mode. An
important source of information about the clock system is the Clock and Reset Generator (CRG) block
description chapter.
1.5.2.1
System Stop Modes
The system stop modes are entered if the CPU executes the STOP instruction and the XGATE doesn’t
execute a thread and the XGFACT bit in the XGMCTL register is cleared. Depending on the state of the
PSTP bit in the CLKSEL register the MCU goes into pseudo stop mode or full stop mode. Please refer to
CRG block description chapter. Asserting RESET, XIRQ, IRQ or any other interrupt ends the system stop
modes.
1.5.2.2
Pseudo Stop Mode
In this mode the clocks are stopped but the oscillator is still running and the real time interrupt (RTI) or
watchdog (COP) submodule can stay active. Other peripherals are turned off. This mode consumes more
current than the system stop mode, but the wake up time from this mode is significantly shorter.
1.5.2.3
Full Stop Mode
The oscillator is stopped in this mode. All clocks are switched off. All counters and dividers remain frozen.
MC9S12XHZ512 Data Sheet, Rev. 1.06
50
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
1.5.2.4
System Wait Mode
This mode is entered when the CPU executes the WAI instruction. In this mode the CPU will not execute
instructions. The internal CPU clock is switched off. All peripherals and the XGATE can be active in
system wait mode. For further power consumption savings, the peripherals can individually turn off their
local clocks. Asserting RESET, XIRQ, IRQ or any other interrupt that has not been masked ends system
wait mode.
1.5.3
Freeze Mode
The enhanced capture timer, pulse width modulator, analog-to-digital converter, the periodic interrupt
timer and the XGATE module provide a software programmable option to freeze the module status during
the background debug module is active. This is useful when debugging application software. For detailed
description of the behavior of the ATD, ECT, PWM, XGATE and PIT when the background debug module
is active consult the corresponding module block description chapters.
1.6
Resets and Interrupts
Consult the S12XCPU block description chapter for information on exception processing.
1.6.1
Vectors
Table 1-9 lists all interrupt sources and vectors in the default order of priority. The interrupt module
(S12XINT) provides an interrupt vector base register (IVBR) to relocate the vectors. Associated with each
I-bit maskable service request is a configuration register. It selects if the service request is enabled, the
service request priority level and whether the service request is handled either by the S12X CPU or by the
XGATE module.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
51
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-9. Interrupt Vector Locations (Sheet 1 of 3)
Vector Address1
XGATE
Channel ID2
Interrupt Source
CCR
Mask
Local Enable
0xFFFE
—
System reset or illegal access reset
None
None
0xFFFC
—
Clock monitor reset
None
PLLCTL (CME, SCME)
0xFFFA
—
COP watchdog reset
None
COP rate select
Vector base + 0xF8
—
Unimplemented instruction trap
None
None
Vector base+ 0xF6
—
SWI
None
None
Vector base+ 0xF4
—
XIRQ
X Bit
None
Vector base+ 0xF2
—
IRQ
I bit
IRQCR (IRQEN)
Vector base+ 0xF0
0x78
Real time interrupt
I bit
CRGINT (RTIE)
Vector base+ 0xEE
0x77
Enhanced capture timer channel 0
I bit
TIE (C0I)
Vector base + 0xEC
0x76
Enhanced capture timer channel 1
I bit
TIE (C1I)
Vector base+ 0xEA
0x75
Enhanced capture timer channel 2
I bit
TIE (C2I)
Vector base+ 0xE8
0x74
Enhanced capture timer channel 3
I bit
TIE (C3I)
Vector base+ 0xE6
0x73
Enhanced capture timer channel 4
I bit
TIE (C4I)
Vector base+ 0xE4
0x72
Enhanced capture timer channel 5
I bit
TIE (C5I)
Vector base + 0xE2
0x71
Enhanced capture timer channel 6
I bit
TIE (C6I)
Vector base+ 0xE0
0x70
Enhanced capture timer channel 7
I bit
TIE (C7I)
Vector base+ 0xDE
0x6F
Enhanced capture timer overflow
I bit
TSRC2 (TOF)
Vector base+ 0xDC
0x6E
Pulse accumulator A overflow
I bit
PACTL (PAOVI)
Vector base + 0xDA
0x6D
Pulse accumulator input edge
I bit
PACTL (PAI)
Vector base + 0xD8
0x6C
SPI
I bit
SPCR1 (SPIE, SPTIE)
Vector base+ 0xD6
0x6B
SCI0
I bit
SCI0CR2
(TIE, TCIE, RIE, ILIE)
Vector base + 0xD4
0x6A
SCI1
I bit
SCI1CR2
(TIE, TCIE, RIE, ILIE)
Vector base + 0xD2
0x69
ATD
I bit
ATDCTL2 (ASCIE)
Vector base + 0xD0
0x68
Reserved
I bit
Reserved
Vector base + 0xCE
0x67
Port AD
I bit
PIEAD (PIEAD7 - PIEAD0)
Vector base + 0xCC
0x66
Reserved
I bit
Reserved
Vector base + 0xCA
0x65
Modulus down counter underflow
I bit
MCCTL(MCZI)
Vector base + 0xC8
0x64
Pulse accumulator B overflow
I bit
PBCTL(PBOVI)
Vector base + 0xC6
0x63
CRG PLL lock
I bit
CRGINT(LOCKIE)
Vector base + 0xC4
0x62
CRG self-clock mode
I bit
CRGINT (SCMIE)
Vector base + 0xC2
0x61
Reserved
I bit
Reserved
Vector base + 0xC0
0x60
IIC0 bus
I bit
IB0CR (IBIE)
Vector base + 0xBE
0x5F
Reserved
I bit
Reserved
MC9S12XHZ512 Data Sheet, Rev. 1.06
52
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-9. Interrupt Vector Locations (Sheet 2 of 3)
Vector Address1
XGATE
Channel ID2
Interrupt Source
CCR
Mask
Local Enable
Vector base + 0xBC
0x5E
Reserved
I bit
Reserved
Vector base + 0xBA
0x5D
EEPROM
I bit
ECNFG (CCIE, CBEIE)
Vector base + 0xB8
0x5C
FLASH
I bit
FCNFG (CCIE, CBEIE)
Vector base + 0xB6
0x5B
CAN0 wake-up
I bit
CAN0RIER (WUPIE)
Vector base + 0xB4
0x5A
CAN0 errors
I bit
CAN0RIER (CSCIE, OVRIE)
Vector base + 0xB2
0x59
CAN0 receive
I bit
CAN0RIER (RXFIE)
Vector base + 0xB0
0x58
CAN0 transmit
I bit
CAN0TIER (TXEIE[2:0])
Vector base + 0xAE
0x57
CAN1 wake-up
I bit
CAN1RIER (WUPIE)
Vector base + 0xAC
0x56
CAN1 errors
I bit
CAN1RIER (CSCIE, OVRIE)
Vector base + 0xAA
0x55
CAN1 receive
I bit
CAN1RIER (RXFIE)
Vector base + 0xA8
0x54
CAN1 transmit
I bit
CAN1TIER (TXEIE[2:0])
Vector base + 0xA6
0x53
Reserved
I bit
Reserved
Vector base + 0xA4
0x52
Reserved
I bit
Reserved
Vector base + 0xA2
0x51
SSD4
I bit
MDC4CTL (MCZIE, AOVIE)
Vector base + 0xA0
0x50
SSD0
I bit
MDC0CTL (MCZIE, AOVIE)
Vector base + 0x9E
0x4F
SSD1
I bit
MDC1CTL (MCZIE, AOVIE)
Vector base+ 0x9C
0x4E
SSD2
I bit
MDC2CTL (MCZIE, AOVIE)
Vector base+ 0x9A
0x4D
SSD3
I bit
MDC3CTL (MCZIE, AOVIE)
Vector base + 0x98
0x4C
SSD5
I bit
MDC5CTL (MCZIE, AOVIE)
Vector base + 0x96
0x4B
Motor Control Timer Overflow
I bit
MCCTL1 (MCOCIE)
Vector base + 0x94
0x4A
Reserved
I bit
Reserved
Vector base + 0x92
0x49
Reserved
I bit
Reserved
Vector base + 0x90
0x48
Reserved
I bit
Reserved
Vector base + 0x8E
0x47
Reserved
I bit
Reserved
Vector base+ 0x8C
0x46
PWM emergency shutdown
I bit
PWMSDN (PWMIE)
Vector base + 0x8A
0x45
Reserved
I bit
Reserved
Vector base + 0x88
0x44
Reserved
I bit
Reserved
Vector base + 0x86
0x43
Reserved
I bit
Reserved
Vector base + 0x84
0x42
Reserved
I bit
Reserved
Vector base + 0x82
0x41
IIC1 Bus
I bit
IB1CR (IBIE)
Vector base + 0x80
0x40
Low-voltage interrupt (LVI)
I bit
VREGCTRL (LVIE)
Vector base + 0x7E
0x3F
Autonomous periodical interrupt (API)
I bit
VREGAPICTRL (APIE)
Vector base + 0x7C
0x3E
Reserved
I bit
Reserved
Vector base + 0x7A
0x3D
Periodic interrupt timer channel 0
I bit
PITINTE (PINTE0)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
53
Chapter 1 MC9S12XHZ Family Device Overview
Table 1-9. Interrupt Vector Locations (Sheet 3 of 3)
Vector Address1
XGATE
Channel ID2
Interrupt Source
CCR
Mask
Local Enable
Vector base + 0x78
0x3C
Periodic interrupt timer channel 1
I bit
PITINTE (PINTE1)
Vector base + 0x76
0x3B
Periodic interrupt timer channel 2
I bit
PITINTE (PINTE2)
Vector base + 0x74
0x3A
Periodic interrupt timer channel 3
I bit
PITINTE (PINTE3)
Vector base + 0x72
0x39
XGATE software trigger 0
I bit
XGMCTL (XGIE)
Vector base + 0x70
0x38
XGATE software trigger 1
I bit
XGMCTL (XGIE)
Vector base + 0x6E
0x37
XGATE software trigger 2
I bit
XGMCTL (XGIE)
Vector base + 0x6C
0x36
XGATE software trigger 3
I bit
XGMCTL (XGIE)
Vector base + 0x6A
0x35
XGATE software trigger 4
I bit
XGMCTL (XGIE)
Vector base + 0x68
0x34
XGATE software trigger 5
I bit
XGMCTL (XGIE)
Vector base + 0x66
0x33
XGATE software trigger 6
I bit
XGMCTL (XGIE)
Vector base + 0x64
0x32
XGATE software trigger 7
I bit
XGMCTL (XGIE)
Vector base + 0x62
—
XGATE software error interrupt
I bit
XGMCTL (XGIE)
Vector base + 0x60
—
S12XCPU RAM access violation
I bit
RAMWPC (AVIE)
Vector base+ 0x12
to
Vector base + 0x5E
—
Reserved
—
Reserved
Vector base + 0x10
—
Spurious interrupt
—
None
1
2
16 bits vector address based
For detailed description of XGATE channel ID refer to XGATE block description chapter
1.6.2
Effects of Reset
When a reset occurs, MCU registers and control bits are changed to known start-up states. Refer to the
respective module block description chapters for register reset states.
1.6.2.1
I/O Pins
Refer to the PIM block description chapter for reset configurations of all peripheral module ports.
1.6.2.2
Memory
The RAM array is not initialized out of reset.
1.7
COP Configuration
The COP timeout rate bits CR[2:0] and the WCOP bit in the COPCTL register are loaded on rising edge
of RESET from the Flash control register FCTL (0x0107) located in the Flash EEPROM block. See
Table 1-10 and Table 1-11 for coding. The FCTL register is loaded from the Flash configuration field byte
at global address 0x7FFF0E during the reset sequence
MC9S12XHZ512 Data Sheet, Rev. 1.06
54
Freescale Semiconductor
Chapter 1 MC9S12XHZ Family Device Overview
NOTE
If the MCU is secured the COP timeout rate is always set to the longest
period (CR[2:0] = 111) after COP reset.
Table 1-10. Initial COP Rate Configuration
NV[2:0] in
FCTL Register
CR[2:0] in
COPCTL Register
000
111
001
110
010
101
011
100
100
011
101
010
110
001
111
000
Table 1-11. Initial WCOP Configuration
1.8
NV[3] in
FCTL Register
WCOP in
COPCTL Register
1
0
0
1
ATD External Trigger Input Connection
The ATD_10B16C module includes four external trigger inputs ETRIG0, ETRIG1, ETRIG2, and
ETRIG3. The external trigger feature allows the user to synchronize ATD conversion to external trigger
events. Table 1-12 shows the connection of the external trigger inputs on MC9S12XHZ Family.
Table 1-12. ATD External Trigger Sources
External Trigger
Input
Connectivity
ETRIG0
Pulse width modulator channel 1
ETRIG1
Pulse width modulator channel 3
ETRIG2
Periodic interrupt timer hardware trigger 0
ETRIG3
Periodic interrupt timer hardware trigger 1
Consult the ATD_10B16C block description chapter for information about the analog-to-digital converter
module.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
55
Chapter 1 MC9S12XHZ Family Device Overview
MC9S12XHZ512 Data Sheet, Rev. 1.06
56
Freescale Semiconductor
Chapter 2
Port Integration Module (S12XHZPIMV1)
2.1
lntroduction
The port integration module establishes the interface between the peripheral modules including the
non-multiplexed external bus interface module (S12X_EBI) and the I/O pins for all ports. It controls the
electrical pin properties as well as the signal prioritization and multiplexing on shared pins.
This section covers:
• Port A, B and K associated with S12X_EBI module and the LCD driver
• Port C and D associated with S12X_EBI module
• Port E associated with S12X_EBI module, the IRQ, XIRQ interrupt inputs, and the LCD driver
• Port AD associated with ATD module (channels 7 through 0) and keyboard wake-up interrupts
• Port L connected to the LCD driver and ATD (channels 15 through 8) modules
• Port M connected to 2 CAN modules
• Port P connected to 1 SCI, 2 IIC and PWM modules
• Port S connected to 2 SCI and 1 SPI modules
• Port T connected to 2 IIC, 1 ECT and LCD driver modules
• Port U, V and W associated with PWM motor control and stepper stall detect modules
Each I/O pin can be configured by several registers: input/output selection, drive strength reduction,
enable and select of pull resistors, wired-or mode selection, interrupt enable, and/or status flags.
2.1.1
Features
A standard port has the following minimum features:
• Input/output selection
• 5-V output drive with two selectable drive strength (or slew rates)
• 5-V digital and analog input
• Input with selectable pull-up or pull-down device
Optional features:
• Open drain for wired-OR connections
• Interrupt input with glitch filtering
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
57
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.1.2
Block Diagram
Figure 2-1 is a block diagram of the S12XHZPIM
Port Integration Module
IOC0
IOC1
IOC2
IOC3
IOC4
IOC5
IOC6
IOC7
SSD5
M2C0M
M2C0P
M2C1M
PWM5 M2C1P
M3C0M
PWM6 M3C0P
M3C1M
PWM7 M3C1P
M4C0M
PWM8 M4C0P
M4C1M
PWM9 M4C1P
M5C0M
PWM10 M5C0P
M5C1M
PWM11 M5C1P
RXCAN0
FP0
FP1
FP2
FP3
FP4
FP5
FP6
FP7
FP8
FP9
FP10
FP11
FP12
FP13
FP14
FP15
Enhanced
Capture
Timer
FP24
FP25
FP26
FP27
SDA0
SCL0
SDA1
SCL1
PTAD
PTU
DDRU
PWM4
CAN0 TXCAN0
RXCAN1
CAN1 TXCAN1
SCI0
RXD0
TXD0
SCI1
RXD1
TXD1
MISO
MOSI
SCK
SS
SPI
PW0
PW1
Pulse
PW2
Width
Modulator PW3
PW4
PW5
PW6
PW7
IIC0
SDA0
SCL0
IIC1
SDA1
SCL1
PTV
SSD4
PWM3
DDRV
SSD3
PWM2
PTW
FP23
PWM1
M0C0M
M0C0P
M0C1M
M0C1P
M1C0M
M1C0P
M1C1M
M1C1P
DDRW
SSD2
M2COSM
M2COSP
M2SINM
M2SINP
M3COSM
M3COSP
M3SINM
M3SINP
M4COSM
M4COSP
M4SINM
M4SINP
M5COSM
M5COSP
M5SINM
M5SINP
PWM0
PTM
SSD1
M0COSM
M0COSP
M0SINM
M0SINP
M1COSM
M1COSP
M1SINM
M1SINP
KWAD0
KWAD1
KWAD2
KWAD3
KWAD4
KWAD5
KWAD6
KWAD7
DDRM
SSD0
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
DDRS
PTS
AN8
AN9 Analog to
AN10 Digital
AN11
Converter
AN12
AN13
AN14
AN15
PTP
ADDR0
ADDR1
ADDR2
ADDR3
ADDR4
ADDR5
ADDR6
ADDR7
ADDR8
ADDR9
ADDR10
ADDR11
ADDR12
ADDR13
ADDR14
ADDR15
FP22
BP0
BP1
BP2
BP3
AN8
AN9
AN10
AN11
AN12
AN13
AN14
AN15
DDRP
DATA8
DATA9
DATA10
DATA11
DATA12
DATA13
DATA14
DATA15
FP20
FP21
LCD Driver
XIRQ
IRQ
RW/WE
LSTRB/LDS/EROMCTL
ECLK
MODA/TAGLO/RE
MODB/TAGHI
XCLKS/ECLKX2
ADDR16/IQSTAT0
ADDR17/IQSTAT1
ADDR18/IQSTAT2
ADDR19/IQSTAT3
ADDR20/ACC0
ADDR21/ACC1
ADDR22/ACC2
EWAIT/ROMCTL
DATA0
DATA1
DATA2
DATA3
DATA4
DATA5
DATA6
DATA7
Non-Multiplexed External Bus Interface
PTL
DDRL
DDRE
PTE
PTK
DDRK
DDRD
PTD
PTC
DDRC
DDRB
PTB
FP16
FP17
FP18
FP19
FP28
FP29
FP30
FP31
Module-to-Port-Routing
PT0
PT1
PT2
PT3
PT4
PT5
PT6
PT7
PTA
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
DDRA
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
PTT
PE0
PE1
PE2
PE3
PE4
PE5
PE6
PE7
PK0
PK1
PK2
PK3
PK4
PK5
PK6
PK7
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
DDRT
PL0
PL1
PL2
PL3
PL4
PL5
PL6
PL7
DDRAD
Single-Wire Background
Debug Module
BKGD
PAD0
PAD1
PAD2
PAD3
PAD4
PAD5
PAD6
PAD7
PU0
PU1
PU2
PU3
PU4
PU5
PU6
PU7
PV0
PV1
PV2
PV3
PV4
PV5
PV6
PV7
PW0
PW1
PW2
PW3
PW4
PW5
PW6
PW7
PM1 CS1
PM2
PM3
PM4
PM5
PS0
PS1
PS2 CS3
PS3
PS4
PS5
PS6
PS7
PP0
PP1
PP2
PP3
PP4
PP5
PP6 CS0
PP7 CS2
Figure 2-1. S12XHZPIM Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
58
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.2
External Signal Description
This section lists and describes the signals that connect off chip.
Table 2-1 shows all the pins and their functions that are controlled by the S12XHZPIM. The order in which
the pin functions are listed represents the functions priority (top – highest priority, bottom – lowest
priority).
Table 2-1. Detailed Signal Descriptions (Sheet 1 of 6)
Port
Pin Name
—
BKGD
A
PA[7:0]
Pin Function
and Priority
I/O
C
PC[7:0]
MODC
BKGD
ADDR[15:8]
mux IVD[15:8]
FP[15:8]
GPIO
ADDR[7:1]
mux IVD[7:1]
FP[7:1]
GPIO
ADDR0
mux IVD0
UDS
FP[0]
GPIO
DATA[15:8]
D
PD[7:0]
GPIO
DATA[7:0]
I/O
I/O
GPIO
I/O
B
PB[7:1]
PB[0]
I
I/O
O
O
I/O
O
O
I/O
O
O
O
I/O
I/O
Description
MODC input during RESET
S12X_BDM communication pin
High-order external bus address output
(multiplexed with IVIS data)
LCD frontplane driver
General-purpose I/O
Low-order external bus address output
(multiplexed with IVIS data)
LCD frontplane driver
General-purpose I/O
Low-order external bus address output
(multiplexed with IVIS data)
Upper data strobe
LCD frontplane driver
General-purpose I/O
High-order bidirectional data input/output
Configurable for reduced input threshold
General-purpose I/O
Low-order bidirectional data input/output
Configurable for reduced input threshold
General-purpose I/O
Pin Function
after Reset
BKGD
Mode dependent
Mode dependent
Mode dependent
Mode dependent
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
59
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-1. Detailed Signal Descriptions (Sheet 2 of 6)
Port
Pin Name
E
PE[7]
PE[6]
PE[5]
PE[4]
PE[3]
PE[2]
PE[1]
PE[0]
K
PK[7]
PK[6:4]
PK[3:0]
AD
PAD[7:0]
Pin Function
and Priority
Pin Function
after Reset
I/O
Description
XCLKS
ECLKX2
FP[22]
GPIO
MODB
TAGHI
I
O
O
I/O
I
I
GPIO
MODA
RE
TAGLO
I/O
I
O
I
GPIO
ECLK
I/O
O
GPIO
EROMCTL
LSTRB
LDS
FP[21]
GPIO
R/W
WE
FP[20]
GPIO
IRQ
GPIO
XIRQ
GPIO
ROMCTL
EWAIT
I/O
I
O
O
O
I/O
O
O
O
I/O
I
I/O
I
I/O
I
FP[23]
GPIO
ADDR[22:20]
mux ACC[2:0]
GPIO
ADDR[19:16]
mux IQSTAT[3:0]
BP[3:0]
GPIO
AN[7:0]
KWAD[7:0]
GPIO
O
I/O
O
External clock selection input during RESET
Free-running clock output at Core Clock rate (ECLK x 2)
LCD frontplane driver
General-purpose I/O
MODB input during RESET
Instruction tagging low pin
Configurable for reduced input threshold
General-purpose I/O
MODA input during RESET
Read enable signal
Instruction tagging low pin
Configurable for reduced input threshold
General-purpose I/O
Free-running clock output at the Bus Clock rate or
programmable divided in normal modes
General-purpose I/O
EROMON bit control input during RESET
Low strobe bar output
Lower data strobe
LCD frontplane driver
General-purpose I/O
Read/write output for external bus
Write enable
LCD frontplane driver
General-purpose I/O
Maskable level or falling edge-sensitive interrupt input
General-purpose I/O
Non-maskable level-sensitive interrupt input
General-purpose I/O
ROMON bit control input during RESET
External Wait signal
Configurable for reduced input threshold
LCD frontplane driver
General-purpose I/O
Extended external bus address output
(multiplexed with master access output)
General-purpose I/O
Extended external bus address output
(multiplexed with instruction pipe status bits)
LCD backplane driver
General-purpose I/O
Analog-to-digital converter input channel
Keyboard wake-up interrupt
General-purpose I/O
I
I/O
O
O
I/O
I
I
I/O
Mode dependent
Mode dependent
GPIO
MC9S12XHZ512 Data Sheet, Rev. 1.06
60
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-1. Detailed Signal Descriptions (Sheet 3 of 6)
Port
Pin Name
L
PL[7:4]
PL[3:0]
M
PM[5]
PM[4]
PM[3]
PM[2]
PM[1]
P
PP[7]
PP[6]
PP[5]
PP[4]
PP[3]
PP[2]
PP[1]
PP[0]
Pin Function
and Priority
I/O
FP[31:28]
AN[15:12]
GPIO
FP[19:16]
AN[11:8]
GPIO
TXCAN1
GPIO
RXCAN1
GPIO
TXCAN0
GPIO
RXCAN0
GPIO
CS1
GPIO
CS2
PWM7
O
I
I/O
O
I
I/O
O
I/O
I
I/O
O
I/O
I
O
O
I/O
O
I/O
SCL1
GPIO
CS0
PWM6
SDA1
GPIO
PWM5
I/O
I/O
O
O
I/O
I/O
I/O
SCL0
GPIO
PWM4
SDA0
GPIO
PWM3
GPIO
PWM2
RXD1
GPIO
PWM1
GPIO
PWM0
TXD1
GPIO
I/O
I/O
O
I/O
I/O
O
I/O
O
I
I/O
O
I/O
O
O
I/O
Description
LCD frontplane driver
Analog-to-digital converter input channel
General-purpose I/O
LCD frontplane driver
Analog-to-digital converter input channel
General-purpose I/O
MSCAN1 transmit pin
General-purpose I/O
MSCAN1 receive pin
General-purpose I/O
MSCAN0 transmit pin
General-purpose I/O
MSCAN0 receive pin
General-purpose I/O
Chip select 1
General-purpose I/O
Chip select 2
Pulse-width modulator channel 7
and emergency shutdown input
Inter-integrated circuit 1 serial clock line
General-purpose I/O
Chip select 0
Pulse-width modulator channel 6
Inter-integrated circuit 1 serial data line
General-purpose I/O
Pulse-width modulator channel 5
and emergency shutdown input
Inter-integrated circuit 0 serial clock line
General-purpose I/O
Pulse-width modulator channel 4
Inter-integrated circuit 0 serial data line
General-purpose I/O
Pulse-width modulator channel 3
General-purpose I/O
Pulse-width modulator channel 2
Serial communication interface 1 receive pin
General-purpose I/O
Pulse-width modulator channel 1
General-purpose I/O
Pulse-width modulator channel 0
Serial communication interface 1 transmit pin
General-purpose I/O
Pin Function
after Reset
GPIO
GPIO
GPIO
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
61
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-1. Detailed Signal Descriptions (Sheet 4 of 6)
Port
Pin Name
S
PS[7]
PS[6]
PS[5]
PS[4]
PS[3]
PS[2]
PS[1]
PS[0]
T
PT[7]
PT[6]
PT[5]
PT[4]
PT[3:0]
Pin Function
and Priority
I/O
SS
I/O
GPIO
SCK
GPIO
MOSI
GPIO
MISO
GPIO
TXD1
GPIO
CS3
RXD1
GPIO
TXD0
GPIO
RXD0
GPIO
IOC7
SCL1
GPIO
IOC7
SDA1
GPIO
IOC5
SCL0
GPIO
IOC4
SDA0
GPIO
FP[27:24]
IOC[3:0]
GPIO
I/O
I/O
I/O
I/O
I/O
I/O
I/O
O
I/O
O
I
I/O
O
I/O
I
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
Pin Function
after Reset
Description
Serial peripheral interface slave select input/output in
master mode, input in slave mode
General-purpose I/O
Serial peripheral interface serial clock pin
General-purpose I/O
Serial peripheral interface master out/slave in pin
General-purpose I/O
Serial peripheral interface master in/slave out pin
General-purpose I/O
Serial communication interface 1 transmit pin
General-purpose I/O
Chip select 3
Serial communication interface 1 receive pin
General-purpose I/O
Serial communication interface 0 transmit pin
General-purpose I/O
Serial communication interface 0 receive pin
General-purpose I/O
Timer channel
Inter-integrated circuit 1 serial clock line
General-purpose I/O
Timer channel
Inter-integrated circuit 1 serial data line
General-purpose I/O
Timer channel
Inter-integrated circuit 0 serial clock line
General-purpose I/O
Timer channel
Inter-integrated circuit 0 serial data line
General-purpose I/O
LCD frontplane driver
Timer channel
General-purpose I/O
GPIO
GPIO
MC9S12XHZ512 Data Sheet, Rev. 1.06
62
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-1. Detailed Signal Descriptions (Sheet 5 of 6)
Port
Pin Name
U
PU[7]
PU[6]
PU[5]
PU[4]
PU[3]
PU[2]
PU[1]
PU[0]
V
PV[7]
PV[6]
PV[5]
PV[4]
PV[3]
PV[2]
PV[1]
PV[0]
Pin Function
and Priority
M1SINP
M1C1P
GPIO
M1SINM
M1C1M
GPIO
M1COSP
M1C0P
GPIO
M1COSM
M1C0M
GPIO
M0SINP
M0C1P
GPIO
M0SINM
M0C1M
GPIO
M0COSP
M0C0P
GPIO
M0COSM
M0C0M
GPIO
M3SINP
M3C1P
GPIO
M3SINM
M3C1M
GPIO
M3COSP
M3C0P
GPIO
M3COSM
M3C0M
GPIO
M2SINP
M2C1P
GPIO
M2SINM
M2C1M
GPIO
M2COSP
M2C0P
GPIO
M2COSM
M2C0M
GPIO
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
Description
SSD1 Sine+ Node
PWM motor controller channel 3
General-purpose I/O
SSD1 Sine- Node
PWM motor controller channel 3
General-purpose I/O
SSD1 Cosine+ Node
PWM motor controller channel 2
General-purpose I/O
SSD1 Cosine- Node
PWM motor controller channel 2
General-purpose I/O
SSD0 Sine+ Node
PWM motor controller channel 1
General-purpose I/O
SSD0 Sine- Node
PWM motor controller channel 1
General-purpose I/O
SSD0 Cosine+ Node
PWM motor controller channel 0
General-purpose I/O
SSD0 Cosine- Node
PWM motor controller channel 0
General-purpose I/O
SSD3 sine+ node
PWM motor controller channel 7
General-purpose I/O
SSD3 sine- node
PWM motor controller channel 7
General-purpose I/O
SSD3 cosine+ node
PWM motor controller channel 6
General-purpose I/O
SSD3 cosine- node
PWM motor controller channel 6
General-purpose I/O
SSD2 sine+ node
PWM motor controller channel 5
General-purpose I/O
SSD2 sine- node
PWM motor controller channel 5
General-purpose I/O
SSD2 cosine+ node
PWM motor controller channel 4
General-purpose I/O
SSD2 cosine- node
PWM motor controller channel 4
General-purpose I/O
Pin Function
after Reset
GPIO
GPIO
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
63
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-1. Detailed Signal Descriptions (Sheet 6 of 6)
Port
Pin Name
W
PW[7]
PW[6]
PW[5]
PW[4]
PW[3]
PW[2]
PW[1]
PW[0]
Pin Function
and Priority
M5SINP
M5C1P
GPIO
M5SINM
M5C1M
GPIO
M5COSP
M5C0P
GPIO
M5COSM
M5C0M
GPIO
M4SINP
M4C1P
GPIO
M4SINM
M4C1M
GPIO
M4COSP
M4C0P
GPIO
M4COSM
M4C0M
GPIO
I/O
Description
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
O
O
I/O
SSD5 sine+ node
PWM motor controller channel 11
General-purpose I/O
SSD5 sine- node
PWM motor controller channel 11
General-purpose I/O
SSD5 cosine+ node
PWM motor controller channel 10
General-purpose I/O
SSD5 cosine- node
PWM motor controller channel 10
General-purpose I/O
SSD4 sine+ node
PWM motor controller channel 9
General-purpose I/O
SSD4 sine- node
PWM motor controller channel 9
General-purpose I/O
SSD4 cosine+ node
PWM motor controller channel 8
General-purpose I/O
SSD4 cosine- node
PWM motor controller channel 8
General-purpose I/O
Pin Function
after Reset
GPIO
MC9S12XHZ512 Data Sheet, Rev. 1.06
64
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3
Memory Map and Register Definition
This section provides a detailed description of all registers. Table 2-2 is a standard memory map of port
integration module.
Table 2-2. S12XHZPIM Memory Map
Address Offset
Use
Access
0x0000
Port A I/O Register (PTA)
R/W
0x0001
Port B I/O Register (PTB)
R/W
0x0002
Port A Data Direction Register (DDRA)
R/W
0x0003
Port B Data Direction Register (DDRB)
R/W
0x0004
Port C I/O Register (PTC)
R/W
0x0005
Port D I/O Register (PTD)
R/W
0x0006
Port C Data Direction Register (DDRC)
R/W
0x0007
Port D Data Direction Register (DDRD)
R/W
0x0008
Port E I/O Register (PTE)
R/W
Port E Data Direction Register (DDRE)
R/W
0x0009
0x000A - 0x000B
Non-PIM address range
—
0x000C
Pull Up/Down Control Register (PUCR)
R/W
0x000D
Reduced Drive Register (RDRIV)
R/W
0x000E - 0x001B
Non-PIM address range
—
0x001C
ECLK Control Register (ECLKCR)
0x001D
Reserved
0x001E
IRQ Control Register (IRQCR)
R/W
Slew Rate Control Register (SRCR)
R/W
0x001F
0x0020 - 0x0031
R/W
—
Non-PIM address range
—
0x0032
Port K I/O Register (PTK)
R/W
0x0033
Port K Data Direction Register (DDRK)
R/W
0x0034 - 0x01FF
Non-PIM address range
—
0x0200
Port T I/O Register (PTT)
R/W
0x0201
Port T Input Register (PTIT)
0x0202
Port T Data Direction Register (DDRT)
0x0203
Port T Reduced Drive Register (RDRT)
R/W
0x0204
Port T Pull Device Enable Register (PERT)
R/W
0x0205
Port T Polarity Select Register (PPST)
R/W
0x0206
Port T Wired-OR Mode Register (WOMT)
R/W
0x0207
Port T Slew Rate Register (SRRT)
R/W
R
R/W
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
65
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-2. S12XHZPIM Memory Map (continued)
Address Offset
Use
Access
0x0208
Port S I/O Register (PTS)
R/W
0x0209
Port S Input Register (PTIS)
0x020A
Port S Data Direction Register (DDRS)
R/W
R
0x020B
Port S Reduced Drive Register (RDRS)
R/W
0x020C
Port S Pull Device Enable Register (PERS)
R/W
0x020D
Port S Polarity Select Register (PPSS)
R/W
0x020E
Port S Wired-OR Mode Register (WOMS)
R/W
0x020F
Port S Slew Rate Register (SRRS)
R/W
0x0210
Port M I/O Register (PTM)
R/W
0x0211
Port M Input Register (PTIM)
0x0212
Port M Data Direction Register (DDRM)
R/W
0x0213
Port M Reduced Drive Register (RDRM)
R/W
0x0214
Port M Pull Device Enable Register (PERM)
R/W
0x0215
Port M Polarity Select Register (PPSM)
R/W
0x0216
Port M Wired-OR Mode Register (WOMM)
R/W
0x0217
Port M Slew Rate Register (SRRM)
R/W
0x0218
Port P I/O Register (PTP)
R/W
0x0219
Port P Input Register (PTIP)
0x021A
Port P Data Direction Register (DDRP)
R/W
R
R
0x021B
Port P Reduced Drive Register (RDRP)
R/W
0x021C
Port P Pull Device Enable Register (PERP)
R/W
0x021D
Port P Polarity Select Register (PPSP)
R/W
0x021E
Port P Wired-OR Mode Register (WOMP)
R/W
Port P Slew Rate Register (SRRP)
R/W
0x021F
0x0220 - 0x022F
Reserved
—
0x0230
Port L I/O Register (PTL)
R/W
0x0231
Port L Input Register (PTIL)
0x0232
Port L Data Direction Register (DDRL)
R/W
0x0233
Port L Reduced Drive Register (RDRL)
R/W
0x0234
Port L Pull Device Enable Register (PERL)
R/W
0x0235
Port L Polarity Select Register (PPSL)
R/W
R
0x0236
Reserved
0x0237
Port L Slew Rate Register (SRRL)
R/W
0x0238
Port U I/O Register (PTU)
R/W
0x0239
Port U Input Register (PTIU)
0x023A
Port U Data Direction Register (DDRU)
R/W
0x023B
Port U Slew Rate Register (SRRU)
R/W
0x023C
Port U Pull Device Enable Register (PERU)
R/W
0x023D
Port U Polarity Select Register (PPSU)
R/W
0x023E - 0x023F
—
Reserved
R
—
MC9S12XHZ512 Data Sheet, Rev. 1.06
66
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-2. S12XHZPIM Memory Map (continued)
Address Offset
Use
Access
0x0240
Port V I/O Register (PTV)
0x0241
Port V Input Register (PTIV)
0x0242
Port V Data Direction Register (DDRV)
R/W
0x0243
Port V Slew Rate Register (SRRV)
R/W
0x0244
Port V Pull Device Enable Register (PERV)
R/W
0x0245
Port V Polarity Select Register (PPSV)
R/W
0x0246 - 0x0247
Reserved
R/W
R
—
0x0248
Port W I/O Register (PTW)
0x0249
Port W Input Register (PTIW)
0x024A
Port W Data Direction Register (DDRW)
R/W
0x024B
Port W Slew Rate Register (SRRW)
R/W
0x024C
Port W Pull Device Enable Register (PERW)
R/W
0x024D
Port W Polarity Select Register (PPSW)
R/W
0x024E - 0x0250
Reserved
R/W
R
—
0x0251
Port AD I/O Register (PTAD)
R/W
0x0252
Reserved
—
0x0253
Port AD Input Register (PTIAD)
R
0x0254
Reserved
—
0x0255
Port AD Data Direction Register (DDRAD)
0x0256
Reserved
0x0257
Port AD Reduced Drive Register (RDRAD)
0x0258
Reserved
0x0259
Port AD Pull Device Enable Register (PERAD)
0x025A
Reserved
0x025B
Port AD Polarity Select Register (PPSAD)
0x025C
Reserved
0x025D
Port AD Interrupt Enable Register (PIEAD)
0x025E
Reserved
0x025F
Port AD Interrupt Flag Register (PIFAD)
0x0260 - 0x027F
R/W
—
R/W
—
R/W
—
R/W
—
R/W
—
Reserved
R/W
—
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
67
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.1
Port A and Port B
Port A and port B are associated with the external address bus outputs ADDR15-ADDR0, the external read
visibility IVD15-IVD0 and the liquid crystal display (LCD) driver. Each pin is assigned to these functions
according to the following priority: LCD Driver > XEBI > general-purpose I/O.
If the corresponding LCD frontplane drivers are enabled (and LCD module is enabled), the FP[15:0]
outputs of the LCD module are available on port B and port A pins.
Refer to the LCD block description chapter for information on enabling and disabling the LCD and its
frontplane drivers.Refer to the S12X_EBI block description chapter for information on external bus.
During reset, port A and port B pins are configured as inputs with pull down.
2.3.1.1
Port A I/O Register (PTA)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTA7
PTA6
PTA5
PTA4
PTA3
PTA2
PTA1
PTA0
XEBI:
ADDR15
mux
IVD15
ADDR14
mux
IVD14
ADDR13
mux
IVD13
ADDR12
mux
IVD12
ADDR11
mux
IVD11
ADDR10
mux
IVD10
ADDR9
mux
IVD9
ADDR8
mux
IVD8
LCD:
FP15
FP14
FP13
FP12
FP11
FP10
FP9
FP8
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-2. Port A I/O Register (PTA)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRAx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRAx) is set to 0 (input) and the LCD frontplane driver is enabled
(and LCD module is enabled), the associated I/O register bit (PTAx) reads “1”.
If the associated data direction bit (DDRAx) is set to 0 (input) and the LCD frontplane driver is disabled
(or LCD module is disabled), a read returns the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
68
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.1.2
Port B I/O Register (PTB)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTB7
PTB6
PTB5
PTB4
PTB3
PTB2
PTB1
PTB0
ADDR7
mux
IVD7
ADDR6
mux
IVD6
ADDR5
mux
IVD5
ADDR4
mux
IVD4
ADDR3
mux
IVD3
ADDR2
mux
IVD2
ADDR1
mux
IVD1
ADDR0
mux
IVD0
or UDS
LCD:
FP7
FP6
FP5
FP4
FP3
FP2
FP1
FP0
Reset
0
0
0
0
0
0
0
0
R
W
XEBI:
Figure 2-3. Port B I/O Register (PTB)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRBx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRBx) is set to 0 (input) and the LCD frontplane driver is enabled
(and LCD module is enabled), the associated I/O register bit (PTBx) reads “1”.
If the associated data direction bit (DDRBx) is set to 0 (input) and the LCD frontplane driver is disabled
(or LCD module is disabled), a read returns the value of the pin.
2.3.1.3
Port A Data Direction Register (DDRA)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRA7
DDRA6
DDRA5
DDRA4
DDRA3
DDRA2
DDRA1
DDRA0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-4. Port A Data Direction Register (DDRA)
Read: Anytime. Write: Anytime.
This register configures port pins PA[7:0] as either input or output.If a LCD frontplane driver is enabled
(and LCD module is enabled), it outputs an analog signal to the corresponding pin and the associated Data
Direction Register bit has no effect. If a LCD frontplane driver is disabled (or LCD module is disabled),
the corresponding Data Direction Register bit reverts to control the I/O direction of the associated pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
69
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-3. DDRA Field Descriptions
Field
7:0
DDRA[7:0]
2.3.1.4
Description
Data Direction Port A
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Port B Data Direction Register (DDRB)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRB7
DDRB6
DDRB5
DDRB4
DDRB3
DDRB2
DDRB1
DDRB0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-5. Port B Data Direction Register (DDRB)
Read: Anytime. Write: Anytime.
This register configures port pins PB[7:0] as either input or output.If a LCD frontplane driver is enabled
(and LCD module is enabled), it outputs an analog signal to the corresponding pin and the associated Data
Direction Register bit has no effect. If a LCD frontplane driver is disabled (or LCD module is disabled),
the corresponding Data Direction Register bit reverts to control the I/O direction of the associated pin.
Table 2-4. DDRB Field Descriptions
Field
7:0
DDRB[7:0]
Description
Data Direction Port B
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
70
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.2
Port C and Port D
Port C and port D pins can be used for either general-purpose I/O or the external data bus input/outputs
DATA15-DATA0. Refer to the S12X_EBI block description chapter for information on external bus.
2.3.2.1
Port C I/O Register (PTC)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTC7
PTC6
PTC5
PTC4
PTC3
PTC2
PTC1
PTC0
XEBI:
DATA15
DATA14
DATA13
DATA12
DATA11
DATA10
DATA9
DATA8
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-6. Port C I/O Register (PTC)
Read: Anytime. Write: Anytime.
If the data direction bit of the associated I/O pin (DDRCx) is set to 1 (output), a write to the corresponding
I/O Register bit sets the value to be driven to the Port C pin. If the data direction bit of the associated I/O
pin (DDRCx) is set to 0 (input), a write to the corresponding I/O Register bit takes place but has no effect
on the Port C pin.
If the associated data direction bit (DDRCx) is set to 1 (output), a read returns the value of the I/O register
bit. If the associated data direction bit (DDRCx) is set to 0 (input), a read returns the value of the pin.
2.3.2.2
Port D I/O Register (PTD)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTD7
PTD6
PTD5
PTD4
PTD3
PTD2
PTD1
PTD0
XEBI:
DATA7
DATA6
DATA5
DATA4
DATA3
DATA2
DATA1
DATA0
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-7. Port D I/O Register (PTD)
Read: Anytime. Write: Anytime.
If the data direction bit of the associated I/O pin (DDRDx) is set to 1 (output), a write to the corresponding
I/O Register bit sets the value to be driven to the Port D pin. If the data direction bit of the associated I/O
pin (DDRDx) is set to 0 (input), a write to the corresponding I/O Register bit takes place but has no effect
on the Port D pin.
If the associated data direction bit (DDRDx) is set to 1 (output), a read returns the value of the I/O register
bit. If the associated data direction bit (DDRDx) is set to 0 (input), a read returns the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
71
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.2.3
Port C Data Direction Register (DDRC)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRC7
DDRC6
DDRC5
DDRC4
DDRC3
DDRC2
DDRC1
DDRC0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-8. Port C Data Direction Register (DDRC)
Read: Anytime. Write: Anytime.
This register configures port pins PC[7:0] as either input or output.
Table 2-5. DDRC Field Descriptions
Field
7:0
DDRC[7:0]
2.3.2.4
Description
Data Direction Port C
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Port D Data Direction Register (DDRD)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRD7
DDRD6
DDRD5
DDRD4
DDRD3
DDRD2
DDRD1
DDRD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-9. Port D Data Direction Register (DDRD)
Read: Anytime. Write: Anytime.
This register configures port pins PD[7:0] as either input or output.
Table 2-6. DDRD Field Descriptions
Field
7:0
DDRD[7:0]
Description
Data Direction Port D
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
72
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.3
Port E
Port E pins can be used for either general-purpose I/O, or the liquid crystal display (LCD) driver, or the
external bus control outputs R/W, WE, LSTRB, LDS and RE, the free running clock outputs ECLK and
ECLKX2, or the inputs TAGHI, TAGLO, MODA, MODB, EROMCTL, XCLKS and interrupts IRQ and
XIRQ. Refer to the LCD block description chapter for information on enabling and disabling the LCD and
its frontplane drivers. Refer to the S12X_EBI block description chapter for information on external bus.
Port E pin PE[7] can be used for either general-purpose I/O, or as the free-running clock ECLKX2 output
running at the core clock rate, or the frontplane driver FP22. The clock ECLKX2 output is always enabled
in emulation modes.
Port E pin PE[4] can be used for either general-purpose I/O or as the free-running clock ECLK output
running at the bus clock rate or at the programmed divided clock rate. The clock output is always enabled
in emulation modes.
Port E pin PE[1] can be used for either general-purpose input or as the level- or falling edge-sensitive IRQ
interrupt inpu. IRQ will be enabled by setting the IRQEN configuration bit and clearing the I-bit in the
CPU’s condition code register. It is inhibited at reset so this pin is initially configured as a simple input
with a pull-up.
Port E pin PE[0] can be used for either general-purpose input or as the level-sensitive XIRQ interrupt
input. XIRQ can be enabled by clearing the X-bit in the CPU’s condition code register. It is inhibited at
reset so this pin is initially configured as a high-impedance input with a pull-up.
2.3.3.1
Port E I/O Register (PTE)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTE7
PTE6
PTE5
PTE4
PTE3
PTE2
PTE1
PTE0
XCLKS1
or
ECLKX2
MODB1
or
TAGHI
MODA1
or
TAGLO
or
RE
ECLK
EROMCTL1
or
LSTRB
or
LDS
R/W
or
WE
IRQ
XIRQ
FP21
FP20
0
0
—2
—2
R
W
XEBI:
LCD:
FP22
Reset
0
0
0
0
Figure 2-10. Port E I/O Register (PTE)
1
2
Function active when RESET asserted.
These registers are reset to zero. Two bus clock cycles after reset release the register values are updated with the associated
pin values.
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDREx) is set to 1 (output), a read returns the value of the I/O register
bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
73
Chapter 2 Port Integration Module (S12XHZPIMV1)
If the associated data direction bit (DDREx) is set to 0 (input) and the LCD frontplane driver is enabled
(and LCD module is enabled), the associated I/O register bit (PTEx) reads “1”.
If the associated data direction bit (DDREx) is set to 0 (input) and the LCD frontplane driver is disabled
(or LCD module is disabled), a read returns the value of the pin.
2.3.3.2
Port E Data Direction Register (DDRE)
Module Base + 0x0055
7
6
5
4
3
2
DDRE7
DDRE6
DDRE5
DDRE4
DDRE3
DDRE2
0
0
0
0
0
0
R
1
0
0
0
0
0
W
Reset
= Reserved or Unimplemented
Figure 2-11. Port E Data Direction Register (DDRE)
Read: Anytime. Write: Anytime.
This register configures port pins PE[7:0] as either input or output.If a LCD frontplane driver is enabled
(and LCD module is enabled), it outputs an analog signal to the corresponding pin and the associated Data
Direction Register bit has no effect. If a LCD frontplane driver is disabled (or LCD module is disabled),
the corresponding Data Direction Register bit reverts to control the I/O direction of the associated pin.
Table 2-7. DDRE Field Descriptions
Field
7:2
DDRE[7:2]
Description
Data Direction Port E
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
74
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.4
Port K
Port K pins can be used for either general-purpose I/O, or the liquid crystal display (LCD) driver, or the
external address bus outputs ADDR22-ADDR16 muxed with master access output ACC2-ACC0 and
instruction pipe signals IQSTAT3-IQSTAT0, or inputs EWAIT and ROMCTL. Refer to the LCD block
description chapter for information on enabling and disabling the LCD and its frontplane drivers. Refer to
the S12X_EBI block description chapter for information on external bus.
2.3.4.1
Port K I/O Register (PTK)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTK7
PTK6
PTK5
PTK4
PTK3
PTK2
PTK1
PTK0
XEBI:
ROMCTL1
or
EWAIT
ADDR22
or
ACC2
ADDR21
or
ACC1
ADDR20
or
ACC0
ADDR19
or
IQSTAT3
ADDR18
or
IQSTAT2
ADDR17
or
IQSTAT1
ADDR16
or
IQSTAT0
LCD:
FP23
BP3
BP2
BP1
BP0
Reset
0
0
0
0
0
R
W
0
0
0
Figure 2-12. Port K I/O Register (PTK)
1
Function active when RESET asserted.
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRKx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRKx) is set to 0 (input) and the LCD frontplane driver is enabled
(and LCD module is enabled), the associated I/O register bit (PTKx) reads “1”.
If the associated data direction bit (DDRKx) is set to 0 (input) and the LCD frontplane driver is disabled
(or LCD module is disabled), a read returns the value of the pin.
2.3.4.2
Port K Data Direction Register (DDRK)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRK7
DDRK6
DDRK5
DDRK4
DDRK3
DDRK2
DDRK1
DDRK0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-13. Port K Data Direction Register (DDRK)
Read: Anytime. Write: Anytime.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
75
Chapter 2 Port Integration Module (S12XHZPIMV1)
This register configures port pins PK[7:0] as either input or output.If a LCD frontplane driver is enabled
(and LCD module is enabled), it outputs an analog signal to the corresponding pin and the associated Data
Direction Register bit has no effect. If a LCD frontplane driver is disabled (or LCD module is disabled),
the corresponding Data Direction Register bit reverts to control the I/O direction of the associated pin.
Table 2-8. DDRK Field Descriptions
Field
7:0
DDRK[7:0]
Description
Data Direction Port K
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
76
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.5
Miscellaneous registers
2.3.5.1
Pull Up/Down Control Register (PUCR)
Module Base + 0x0055
7
6
5
PUPKE
BKGPE
1
1
R
4
3
2
1
0
PUPEE
PUPDE
PUPCE
PUPBE
PUPAE
1
0
0
1
1
0
W
Reset
0
Figure 2-14. Pull Up/Down Control Register (PUCR)
Read: Anytime. Write: Anytime except BKPUE which is writable in special test mode only.
This register is used to enable pull up/down devices for the associated ports A, B, C, D, E and K. Pull
up/down devices are assigned on a per-port basis and apply to any pin in the corresponding port currently
configured as an input.
Table 2-9. PUCR Field Descriptions
Field
Description
7
PUPKE
Pull-down Port K Enable
0 Port K pull-down devices are disabled.
1 Enable pull-down devices for Port K input pins.
6
BKPUE
BKGD Pin Pull-up Enable
0 BKGD pull-up device is disabled.
1 Enable pull-up device on BKGD pin.
4
PUPEE
Pull Port E Enable
0 Port E pull-down devices on pins 7, 4–2 are disabled. Port E pull-up devices on pins 1–0 are disabled.
1 Enable pull-down devices for Port E input pins 7, 4–2. Enable pull-up devices for Port E input pins 1–0.
Note: Bits 5 and 6 of Port E have pull-down devices which are only enabled during reset. This bit has no effect
on these pins.
3
PUPDE
Pull-up Port D Enable
0 Port D pull-up devices are disabled.
1 Enable pull-up devices for all Port D input pins.
2
PUPCE
Pull-up Port C Enable
0 Port C pull-up devices are disabled.
1 Enable pull-up devices for all Port C.
1
PUPBE
Pull-down Port B Enable
0 Port B pull-down devices are disabled.
1 Enable pull-down devices for all Port B input pins.
0
PUPAE
Pull-down Port A Enable
0 Port A pull-down devices are disabled.
1 Enable pull-down devices for all Port A input pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
77
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.5.2
Reduced Drive Register (RDRIV)
Module Base + 0x0055
7
R
6
5
0
0
RDPK
4
3
2
1
0
RDPE
RDPD
RDPC
RDPB
RDPA
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-15. Reduced Drive Register (RDRIV)
Read: Anytime. Write: Anytime.
This register is used to select reduced drive for the pins associated with ports A, B, C, D, E, and K. If
enabled, the pins drive at about 1/6 of the full drive strength. The reduced drive function is independent of
which function is being used on a particular pin.
The reduced drive functionality does not take effect on the pins in emulation modes.
Table 2-10. RDRIV Field Descriptions
Field
Description
7
RDPK
Reduced Drive of Port K
0 All port K output pins have full drive enabled.
1 All port K output pins have reduced drive enabled.
4
RDPE
Reduced Drive of Port E
0 All port E output pins have full drive enabled.
1 All port E output pins have reduced drive enabled.
3
RDPD
Reduced Drive of Port D
0 All port D output pins have full drive enabled.
1 All port D output pins have reduced drive enabled.
2
RDPC
Reduced Drive of Port C
0 All Port C output pins have full drive enabled.
1 All port C output pins have reduced drive enabled.
1
RDPB
Reduced Drive of Port B
0 All port B output pins have full drive enabled.
1 All port B output pins have reduced drive enabled.
0
RDPA
Reduced Drive of Port A
0 All Port A output pins have full drive enabled.
1 All port A output pins have reduced drive enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
78
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.5.3
ECLK Control Register (ECLKCR)
Module Base + 0x0055
7
6
NECLK
NCLKX2
01
1
R
5
4
3
2
0
0
0
0
1
0
EDIV1
EDIV0
0
0
W
Reset
0
0
0
0
= Reserved or Unimplemented
Figure 2-16. ECLK Control Register (ECLKCR)
1
NECLK reset value is 1 in emulation single-chip and normal single-chip modes.
Read: Anytime. Write: Anytime.
The ECLKCTL register is used to control the availability of the free-running clocks and the free-running
clock divider.
Table 2-11. ECLKCTL Field Descriptions
Field
Description
7
NECLK
No ECLK — This bit controls the availability of a free-running clock on the ECLK pin. Clock output is always
active in emulation modes and if enabled in all other operating modes.
0 ECLK enabled
1 ECLK disabled
6
NCLKX2
No ECLKX2 — This bit controls the availability of a free-running clock on the ECLKX2 pin. This clock has a fixed
rate of twice the internal bus clock. Clock output is always active in emulation modes and if enabled in all other
operating modes.
0 ECLKX2 is enabled
1 ECLKX2 is disabled
1–0
EDIV[1:0]
Free-Running ECLK Divider — These bits determine the rate of the free-running clock on the ECLK pinr. The
usage of the bits is shown in Table 2-12. Divider is always disabled in emulation modes and active as
programmed in all other operating modes.
Table 2-12. Free-Running ECLK Clock Rate
EDIV[1:0]
Rate of Free-Running ECLK
00
ECLK = Bus clock rate
01
ECLK = Bus clock rate divided by 2
10
ECLK = Bus clock rate divided by 3
11
ECLK = Bus clock rate divided by 4
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
79
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.5.4
IRQ Control Register (IRQCR)
Module Base + 0x0055
7
6
IRQE
IRQEN
0
1
R
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Reserved or Unimplemented
Figure 2-17. Port E Data Direction Register (DDRE)
Read: See individual bit descriptions below.
Write: See individual bit descriptions below.
Table 2-13. IRQCR Field Descriptions
Field
7
IRQE
6
IRQEN
Description
IRQ Select Edge Sensitive Only
Special modes: Read or write anytime.
Normal and emulation modes: Read anytime, write once.
0 IRQ configured for low level recognition.
1 IRQ configured to respond only to falling edges. Falling edges on the IRQ pin will be detected anytime
IRQE = 1. The edge detector is cleared only upon the servicing of the IRQ interrupt or a reset .
External IRQ Enable
Read or write anytime.
0 External IRQ pin is disconnected from interrupt logic.
1 External IRQ pin is connected to interrupt logic.
MC9S12XHZ512 Data Sheet, Rev. 1.06
80
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.5.5
Slew Rate Control Register (SRCR)
Module Base + 0x0055
7
R
6
5
0
0
SRRK
4
3
2
1
0
SRRE
SRRD
SRRC
SRRB
SRRA
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-18. Slew Rate Control Register (SRCR)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for the pins associated with
ports A, B, C, D, E, and K.
Table 2-14. SRCR Field Descriptions
Field
Description
7
SRRK
Slew Rate of Port K
0 Disables slew rate control and enables digital input buffer for all port K pins.
1 Enables slew rate control and disables digital input buffer for all port K pins.
4
SRRE
Slew Rate of Port E
0 Disables slew rate control and enables digital input buffer for all port E pins.
1 Enables slew rate control and disables digital input buffer for all port E pins.
3
SRRD
Slew Rate of Port D
0 Disables slew rate control and enables digital input buffer for all port D pins.
1 Enables slew rate control and disables digital input buffer for all port D pins.
2
SRRC
Slew Rate of Port C
0 Disables slew rate control and enables digital input buffer for all port C pins.
1 Enables slew rate control and disables digital input buffer for all port C pins.
1
SRRB
Slew Rate of Port B
0 Disables slew rate control and enables digital input buffer for all port B pins.
1 Enables slew rate control and disables digital input buffer for all port B pins.
0
SRRA
Slew Rate of Port A
0 Disables slew rate control and enables digital input buffer for all port A pins.
1 Enables slew rate control and disables digital input buffer for all port A pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
81
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.6
Port AD
Port AD is associated with the analog-to-digital converter (ATD) and keyboard wake-up (KWU) interrupts
. Each pin is assigned to these modules according to the following priority: ATD > KWU >
general-purpose I/O.
For the pins of port AD to be used as inputs, the corresponding bits of the ATDDIEN1 register in the ATD
module must be set to 1 (digital input buffer is enabled). The ATDDIEN1 register does not affect the port
AD pins when they are configured as outputs.
Refer to the ATD block description chapter for information on the ATDDIEN1 register.
During reset, port AD pins are configured as high-impedance analog inputs (digital input buffer is
disabled).
2.3.6.1
Port AD I/O Register (PTAD)
Module Base + 0x0051
7
6
5
4
3
2
1
0
PTAD7
PTAD6
PTAD5
PTAD4
PTAD3
PTAD2
PTAD1
PTAD0
KWU:
KWAD7
KWAD6
KWAD5
KWAD4
KWAD3
KWAD2
KWAD1
KWAD0
ATD:
AN7
AN6
AN55
AN4
AN3
AN2
AN1
AN0
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-19. Port AD I/O Register (PTAD)
Read: Anytime. Write: Anytime.
If the data direction bit of the associated I/O pin (DDRADx) is set to 1 (output), a write to the
corresponding I/O Register bit sets the value to be driven to the Port AD pin. If the data direction bit of the
associated I/O pin (DDRADx) is set to 0 (input), a write to the corresponding I/O Register bit takes place
but has no effect on the Port AD pin.
If the associated data direction bit (DDRADx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRADx) is set to 0 (input) and the associated ATDDIEN1 bits is set
to 0 (digital input buffer is disabled), the associated I/O register bit (PTADx) reads “1”.
If the associated data direction bit (DDRADx) is set to 0 (input) and the associated ATDDIEN1 bits is set
to 1 (digital input buffer is enabled), a read returns the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
82
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.6.2
Port AD Input Register (PTIAD)
Module Base + 0x0053
R
7
6
5
4
3
2
1
0
PTIAD7
PTIAD6
PTIAD5
PTIAD4
PTIAD3
PTIAD2
PTIAD1
PTIAD0
1
1
1
1
1
1
1
1
W
Reset
= Reserved or Unimplemented
Figure 2-20. Port AD Input Register (PTIAD)
Read: Anytime. Write: Never; writes to these registers have no effect.
If the ATDDIEN1 bit of the associated I/O pin is set to 0 (digital input buffer is disabled), a read returns a
1. If the ATDDIEN1 bit of the associated I/O pin is set to 1 (digital input buffer is enabled), a read returns
the status of the associated pin.
2.3.6.3
Port AD Data Direction Register (DDRAD)
Module Base + 0x0055
7
6
5
4
3
2
1
0
DDRAD7
DDRAD6
DDRAD5
DDRAD4
DDRAD3
DDRAD2
DDRAD1
DDRAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-21. Port AD Data Direction Register (DDRAD)
Read: Anytime. Write: Anytime.
This register configures port pins PAD[7:0] as either input or output.
If a data direction bit is 0 (pin configured as input), then a read value on PTADx depends on the associated
ATDDIEN1 bit. If the associated ATDDIEN1 bit is set to 1 (digital input buffer is enabled), a read on
PTADx returns the value on port AD pin. If the associated ATDDIEN1 bit is set to 0 (digital input buffer
is disabled), a read on PTADx returns a 1.
Table 2-15. DDRAD Field Descriptions
Field
Description
7:0
Data Direction Port AD
DDRAD[7:0] 0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
83
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.6.4
Port AD Reduced Drive Register (RDRAD)
Module Base + 0x0057
7
6
5
4
3
2
1
0
RDRAD7
RDRAD6
RDRAD5
RDRAD4
RDRAD3
RDRAD2
RDRAD1
RDRAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-22. Port AD Reduced Drive Register (RDRAD)
Read: Anytime. Write: Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
Table 2-16. RDRAD Field Descriptions
Field
Description
7:0
Reduced Drive Port A
RDRAD[7:0] 0 Full drive strength at output.
1 Associated pin drives at about 1/3 of the full drive strength.
2.3.6.5
Port AD Pull Device Enable Register (PERAD)
Module Base + 0x0059
7
6
5
4
3
2
1
0
PERAD7
PERAD6
PERAD5
PERAD4
PERAD3
PERAD2
PERAD1
PERAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-23. Port AD Pull Device Enable Register (PERAD)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-17. PERAD Field Descriptions
Field
Description
7:0
Pull Device Enable Port AD
PERAD[7:0] 0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
84
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.6.6
Port AD Polarity Select Register (PPSAD)
Module Base + 0x005B
7
6
5
4
3
2
1
0
PPSAD7
PPSAD6
PPSAD5
PPSAD4
PPSAD3
PPSAD2
PPSAD1
PPSAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-24. Port AD Polarity Select Register (PPSAD)
Read: Anytime. Write: Anytime.
The Port AD Polarity Select Register serves a dual purpose by selecting the polarity of the active interrupt
edge as well as selecting a pull-up or pull-down device if enabled (PERADx = 1). The Port AD Polarity
Select Register is effective only when the corresponding Data Direction Register bit is set to 0 (input).
In pull-down mode (PPSADx = 1), a rising edge on a port AD pin sets the corresponding PIFADx bit. In
pull-up mode (PPSADx = 0), a falling edge on a port AD pin sets the corresponding PIFADx bit.
Table 2-18. PPSAD Field Descriptions
Field
Description
7:0
Polarity Select Port AD
PPSAD[7:0] 0 A pull-up device is connected to the associated port AD pin, and detects falling edge for interrupt generation.
1 A pull-down device is connected to the associated port AD pin, and detects rising edge for interrupt
generation.
2.3.6.7
Port AD Interrupt Enable Register (PIEAD)
Module Base + 0x005D
7
6
5
4
3
2
1
0
PIEAD7
PIEAD6
PIEAD5
PIEAD4
PIEAD3
PIEAD2
PIEAD1
PIEAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-25. Port AD Interrupt Enable Register (PIEAD)
Read: Anytime. Write: Anytime.
This register disables or enables on a per pin basis the edge sensitive external interrupt associated with
port AD.
Table 2-19. PIEAD Field Descriptions
Field
7:0
PIEAD[7:0]
Description
Interrupt Enable Port AD
0 Interrupt is disabled (interrupt flag masked).
1 Interrupt is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
85
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.6.8
Port AD Interrupt Flag Register (PIFAD)
Module Base + 0x005F
7
6
5
4
3
2
1
0
PIFAD7
PIFAD6
PIFAD5
PIFAD4
PIFAD3
PIFAD2
PIFAD1
PIFAD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-26. Port AD Interrupt Flag Register (PIFAD)
Read: Anytime. Write: Anytime.
Each flag is set by an active edge on the associated input pin. The active edge could be rising or falling
based on the state of the corresponding PPSADx bit. To clear each flag, write “1” to the corresponding
PIFADx bit. Writing a “0” has no effect.
NOTE
If the ATDDIEN1 bit of the associated pin is set to 0 (digital input buffer is
disabled), active edges can not be detected.
Table 2-20. PIFAD Field Descriptions
Field
7:0
PIFAD[7:0]
Description
Interrupt Flags Port AD
0 No active edge pending. Writing a “0” has no effect.
1 Active edge on the associated bit has occurred (an interrupt will occur if the associated enable bit is set).
Writing a “1” clears the associated flag.
MC9S12XHZ512 Data Sheet, Rev. 1.06
86
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.7
Port L
Port L is associated with the analog-to-digital converter (ATD) and the liquid crystal display (LCD) driver.
If the ATD module is enabled, the AN[15:8] inputs of ATD module are available on port L pins PL[7:0].
If the corresponding LCD frontplane drivers are enabled, the FP[31:28] and FP[19:16] outputs of LCD
module are available on port L pins PL[7:0] and the general purpose I/Os are disabled.
For the pins of port L to be used as inputs, the corresponding LCD frontplane drivers must be disabled and
the associated ATDDIEN0 register in the ATD module must be set to 1 (digital input buffer is enabled).
The ATDDIEN0 register does not affect the port L pins when they are configured as outputs.
Refer to the LCD block description chapter for information on enabling and disabling the LCD and its
frontplane drivers. Refer to the ATD block description chapter for information on the ATDDIEN0 register.
During reset, port L pins are configured as inputs with pull down.
2.3.7.1
Port L I/O Register (PTL)
Module Base + 0x0030
7
6
5
4
3
2
1
0
PTL7
PTL6
PTL5
PTL4
PTL3
PTL2
PTL1
PTL0
ATD:
AN15
AN14
AN13
AN12
AN11
AN10
AN9
AN8
LCD:
1
1
1
1
1
1
1
1
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-27. Port L I/O Register (PTL)
Read: Anytime. Write: Anytime.
If the data direction bit of the associated I/O pin (DDRLx) is set to 1 (output), a write to the corresponding
I/O Register bit sets the value to be driven to the Port L pin. If the data direction bit of the associated I/O
pin (DDRLx) is set to 0 (input), a write to the corresponding I/O Register bit takes place but has no effect
on the Port L pin.
If the associated data direction bit (DDRLx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRLx) is set to 0 (input) and the associated ATDDIEN0 bits is set to
0 (digital input buffer is disabled), the associated I/O register bit (PTLx) reads “1”.
If the associated data direction bit (DDRLx) is set to 0 (input), the associated ATDDIEN0 bit is set to 1
(digital input buffer is enabled), and the LCD frontplane driver is enabled (and LCD module is enabled),
the associated I/O register bit (PTLx) reads “1”.
If the associated data direction bit (DDRLx) is set to 0 (input), the associated ATDDIEN0 bit is set to 1
(digital input buffer is enabled), and the LCD frontplane driver is disabled (or LCD module is disabled),
a read returns the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
87
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.7.2
Port L Input Register (PTIL)
Module Base + 0x0031
R
7
6
5
4
3
2
1
0
PTIL7
PTIL6
PTIL5
PTIL4
PTIL3
PTIL2
PTIL1
PTIL0
1
1
1
1
1
1
1
1
W
Reset
= Reserved or Unimplemented
Figure 2-28. Port L Input Register (PTIL)
Read: Anytime. Write: Never, writes to this register have no effect.
If the LCD frontplane driver of an associated I/O pin is enabled (and LCD module is enabled) or the
associated ATDDIEN0 bit is set to 0 (digital input buffer is disabled), a read returns a 1.
If the LCD frontplane driver of an associated I/O pin is disabled (or LCD module is disabled) and the
associated ATDDIEN0 bit is set to 1 (digital input buffer is enabled), a read returns the status of the
associated pin.
2.3.7.3
Port L Data Direction Register (DDRL)
Module Base + 0x0032
7
6
5
4
3
2
1
0
DDRL7
DDRL6
DDRL5
DDRL4
DDRL3
DDRL2
DDRL1
DDRL0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-29. Port L Data Direction Register (DDRL)
Read: Anytime. Write: Anytime.
This register configures port pins PL[7:0] as either input or output.
If a LCD frontplane driver is enabled (and LCD module is enabled), it outputs an analog signal to the
corresponding pin and the associated Data Direction Register bit has no effect. If a LCD frontplane driver
is disabled (or LCD module is disabled), the corresponding Data Direction Register bit reverts to control
the I/O direction of the associated pin.
Table 2-21. DDRL Field Descriptions
Field
7:0
DDRL[7:0]
Description
Data Direction Port L
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
88
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.7.4
Port L Reduced Drive Register (RDRL)
Module Base + 0x0033
7
6
5
4
3
2
1
0
RDRL7
RDRL6
RDRL5
RDRL4
RDRL3
RDRL2
RDRL1
RDRL0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-30. Port L Reduced Drive Register (RDRL)
Read: Anytime. Write: Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
Table 2-22. RDRL Field Descriptions
Field
7:0
RDRL[7:0]
2.3.7.5
Description
Reduced Drive Port L
0 Full drive strength at output.
1 Associated pin drives at about 1/3 of the full drive strength.
Port L Pull Device Enable Register (PERL)
Module Base + 0x0034
7
6
5
4
3
2
1
0
PERL7
PERL6
PERL5
PERL4
PERL3
PERL2
PERL1
PERL0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 2-31. Port L Pull Device Enable Register (PERL)
Read:Anytime. Write:Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-23. PERL Field Descriptions
Field
7:0
PERL[7:0]
Description
Pull Device Enable Port L
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
89
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.7.6
Port L Polarity Select Register (PPSL)
Module Base + 0x0035
7
6
5
4
3
2
1
0
PPSL7
PPSL6
PPSL5
PPSL4
PPSL3
PPSL2
PPSL1
PPSL0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 2-32. Port L Polarity Select Register (PPSL)
Read: Anytime. Write: Anytime.
The Port L Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port L Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 2-24. PPSL Field Descriptions
Field
7:0
PPSL[7:0]
2.3.7.7
Description
Pull Select Port L
0 A pull-up device is connected to the associated port L pin.
1 A pull-down device is connected to the associated port L pin.
Port L Slew Rate Register (SRRL)
Module Base + 0x003B
7
6
5
4
3
2
1
0
SRRL7
SRRL6
SRRL5
SRRL4
SRRL3
SRRL2
SRRL1
SRRL0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-33. Port L Slew Rate Register (SRRL)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PL[7:0].
Table 2-25. SRRL Field Descriptions
Field
7:0
SRRL[7:0]
Description
Slew Rate Port L
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
MC9S12XHZ512 Data Sheet, Rev. 1.06
90
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.8
Port M
Port M is associated with the chip select 1 and the Freescale’s scalable controller area network (CAN1 and
CAN0) modules. Each pin is assigned to these modules according to the following priority:
CS1/CAN1/CAN0 > general-purpose I/O.
When the CAN1 module is enabled, PM[5:4] pins become TXCAN1 (transmitter) and RXCAN1
(receiver) pins for the CAN1 module. When the CAN0 module is enabled, PM[3:2] pins become TXCAN0
(transmitter) and RXCAN0 (receiver) pins for the CAN0 module. Refer to the MSCAN block description
chapter for information on enabling and disabling the CAN module.
During reset, port M pins are configured as high-impedance inputs.
2.3.8.1
Port M I/O Register (PTM)
Module Base + 0x0010
R
7
6
0
0
5
4
3
2
1
PTM5
PTM4
PTM3
PTM2
PTM1
TXCAN1
RXCAN1
TXCAN0
RXCAN0
0
0
W
CAN0/CAN1:
CS1
Chip Select:
Reset
0
0
0
0
0
0
0
0
= Reserved or Unimplemented
Figure 2-34. Port M I/O Register (PTM)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRMx) is set to 1 (output), a read returns the value of the I/O register
bit. If the associated data direction bit (DDRMx) is set to 0 (input), a read returns the value of the pin.
2.3.8.2
Port M Input Register (PTIM)
Module Base + 0x0011
R
7
6
5
4
3
2
1
0
0
0
PTIM5
PTIM4
PTIM3
PTIM2
PTIM1
0
0
0
u
u
u
u
u
0
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-35. Port M Input Register (PTIM)
Read: Anytime. Write: Never, writes to this register have no effect.
This register always reads back the status of the associated pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
91
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.8.3
Port M Data Direction Register (DDRM)
Module Base + 0x0012
R
7
6
0
0
5
4
3
2
1
DDRM5
DDRM4
DDRM3
DDRM2
DDRM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-36. Port M Data Direction Register (DDRM)
Read: Anytime. Write: Anytime.
This register configures port pins PM[5:1] as either input or output.
When a CAN module is enabled, the corresponding transmitter (TXCANx) pin becomes an output, the
corresponding receiver (RXCANx) pin becomes an input, and the associated Data Direction Register bits
have no effect. If a CAN module is disabled, the corresponding Data Direction Register bit reverts to
control the I/O direction of the associated pin.
Table 2-26. DDRM Field Descriptions
Field
5:1
DDRM[5:1]
2.3.8.4
Description
Data Direction Port M
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Port M Reduced Drive Register (RDRM)
Module Base + 0x0013
R
7
6
0
0
5
4
3
2
1
RDRM5
RDRM4
RDRM3
RDRM2
RDRM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-37. Port M Reduced Drive Register (RDRM)
Read: Anytime. Write: Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
MC9S12XHZ512 Data Sheet, Rev. 1.06
92
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-27. RDRM Field Descriptions
Field
5:1
RDRM[5:1]
2.3.8.5
Description
Reduced Drive Port M
0 Full drive strength at output
1 Associated pin drives at about 1/3 of the full drive strength.
Port M Pull Device Enable Register (PERM)
Module Base + 0x0014
R
7
6
0
0
5
4
3
2
1
PERM5
PERM4
PERM3
PERM2
PERM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-38. Port M Pull Device Enable Register (PERM)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input or
wired-or output pins. If a pin is configured as push-pull output, the corresponding Pull Device Enable
Register bit has no effect.
Table 2-28. PERM Field Descriptions
Field
5:1
PERM[5:1]
2.3.8.6
Description
Pull Device Enable Port M
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
Port M Polarity Select Register (PPSM)
Module Base + 0x0015
R
7
6
0
0
5
4
3
2
1
PPSM5
PPSM4
PPSM3
PPSM2
PPSM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-39. Port M Polarity Select Register (PPSM)
Read: Anytime. Write: Anytime.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
93
Chapter 2 Port Integration Module (S12XHZPIMV1)
The Port M Polarity Select Register selects whether a pull-down or a pull-up device is connected to the
pin. The Port M Polarity Select Register is effective only when the corresponding Data Direction Register
bit is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
If a CAN module is enabled, a pull-up device can be activated on the receiver pin, and on the transmitter
pin if the corresponding wired-OR mode bit is set. Pull-down devices can not be activated on CAN pins.
Table 2-29. PPSM Field Descriptions
Field
5:1
PPSM[5:1]
2.3.8.7
Description
Pull Select Port M
0 A pull-up device is connected to the associated port M pin.
1 A pull-down device is connected to the associated port M pin.
Port M Wired-OR Mode Register (WOMM)
Module Base + 0x0016
R
7
6
0
0
5
4
3
2
1
WOMM5
WOMM4
WOMM3
WOMM2
WOMM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-40. Port M Wired-OR Mode Register (WOMM)
Read: Anytime. Write: Anytime.
This register selects whether a port M output is configured as push-pull or wired-or. When a Wired-OR
Mode Register bit is set to 1, the corresponding output pin is driven active low only (open drain) and a
high level is not driven. A Wired-OR Mode Register bit has no effect if the corresponding pin is configured
as an input.
These bits apply also to the CAN transmitter and allow a multipoint connection of several serial modules.
Table 2-30. WOMM Field Descriptions
Field
Description
5:1
Wired-OR Mode Port M
WOMM[5:1] 0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
MC9S12XHZ512 Data Sheet, Rev. 1.06
94
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.8.8
Port M Slew Rate Register (SRRM)
Module Base + 0x003B
R
7
6
0
0
5
4
3
2
1
SRRM5
SRRM4
SRRM3
SRRM2
SRRM1
0
0
0
0
0
0
0
W
Reset
0
0
0
= Reserved or Unimplemented
Figure 2-41. Port M Slew Rate Register (SRRM)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PM[5:1].
Table 2-31. SRRM Field Descriptions
Field
5:1
SRRM[5:1]
Description
Slew Rate Port M
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
95
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.9
Port P
Port P is associated with the chip selects 0 and 2, the Pulse Width Modulator (PWM), the serial
communication interface (SCI1) and the Inter-IC bus (IIC0 and IIC1) modules. Each pin is assigned to
these modules according to the following priority: CS0/CS2 > PWM > SCI1/IIC1/IIC0 > general-purpose
I/O.
When a PWM channel is enabled, the corresponding pin becomes a PWM output with the exception of
PP[5] which can be PWM input or output. Refer to the PWM block description chapter for information on
enabling and disabling the PWM channels.
When the IIC1 module is enabled and MODRR1 is clear, PP[7:6] pins become SCL1 and SDA1
respectively as long as the corresponding PWM channels are disabled. When the IIC0 module is enabled
and MODRR0 is clear, PP[5:4] pins become SCL0 and SDA0 respectively as long as the corresponding
PWM channels are disabled. Refer to the IIC block description chapter for information on enabling and
disabling the IIC bus.
When the SCI1 receiver and transmitter are enabled and MODRR2 is clear, the PP[2] and PP[0] pins
become RXD1 and TXD1 respectively as long as the corresponding PWM channels are disabled. Refer to
the SCI block description chapter for information on enabling and disabling the SCI receiver and
transmitter.
During reset, port P pins are configured as high-impedance inputs.
2.3.9.1
Port P I/O Register (PTP)
Module Base + 0x0018
7
6
5
4
3
2
1
0
PTP7
PTP6
PTP5
PTP4
PTP3
PTP2
PTP1
PTP0
SCI1/
IIC1/IIC0:
SCL1
SDA1
SCL0
SDA0
PWM:
PWM7
PWM6
PWM5
PWM4
PWM3
PWM2
PWM1
PWM0
Chip
Select:
CS2
CS0
Reset
0
0
0
0
0
0
0
0
R
W
RXD1
TXD1
Figure 2-42. Port P I/O Register (PTP)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRPx) is set to 1 (output), a read returns the value of the I/O register
bit. If the associated data direction bit (DDRPx) is set to 0 (input), a read returns the value of the pin.
The PWM function takes precedence over the general-purpose I/O function if the associated PWM
channel is enabled. The PWM channels 6-0 are outputs if the respective channels are enabled. PWM
channel 7 can be an output, or an input if the shutdown feature is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
96
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
The IIC function takes precedence over the general-purpose I/O function if the IIC bus is enabled and the
corresponding PWM channels remain disabled. The SDA and SCL pins are bidirectional with outputs
configured as open-drain.
If enabled, the SCI1 transmitter takes precedence over the general-purpose I/O function, and the
corresponding TXD1 pin is configured as an output. If enabled, the SCI1 receiver takes precedence over
the general-purpose I/O function, and the corresponding RXD1 pin is configured as an input.
2.3.9.2
Port P Input Register (PTIP)
Module Base + 0x0019
R
7
6
5
4
3
2
1
0
PTIP7
PTIP6
PTIP5
PTIP4
PTIP3
PTIP2
PTIP1
PTIP0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-43. Port P I/O Register (PTP)
Read: Anytime. Write: Never, writes to this register have no effect.
This register always reads back the status of the associated pins.
2.3.9.3
Port P Data Direction Register (DDRP)
Module Base + 0x001A
7
6
5
4
3
2
1
0
DDRP7
DDRP6
DDRP5
DDRP4
DDRP3
DDRP2
DDRP1
DDRP0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-44. Port P Data Direction Register (DDRP)
Read: Anytime. Write: Anytime.
This register configures port pins PP[7:0] as either input or output.
If a PWM channel is enabled, the corresponding pin is forced to be an output and the associated Data
Direction Register bit has no effect. Channel 5 can also force the corresponding pin to be an input if the
shutdown feature is enabled.
When an IIC bus is enabled, the corresponding pins become the SCL and SDA bidirectional pins
respectively as long as the corresponding PWM channels are disabled. The associated Data Direction
Register bits have no effect.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
97
Chapter 2 Port Integration Module (S12XHZPIMV1)
When the SCI1 transmitter is enabled, the PP[0] pin becomes the TXD1 output pin and the associated Data
Direction Register bit has no effect. When the SCI1 receiver is enabled, the PP[2] pin becomes the RXD1
input pin and the associated Data Direction Register bit has no effect.
If the PWM, IIC0, IIC1 and SCI1 functions are disabled, the corresponding Data Direction Register bit
reverts to control the I/O direction of the associated pin.
Table 2-32. DDRP Field Descriptions
Field
7:0
DDRP[7:0]
2.3.9.4
Description
Data Direction Port P
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Port P Reduced Drive Register (RDRP)
Module Base + 0x001B
7
6
5
4
3
2
1
0
RDRP7
RDRP6
RDRP5
RDRP4
RDRP3
RDRP2
RDRP1
RDRP0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-45. Port P Reduced Drive Register (RDRP)
Read:Anytime. Write:Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
Table 2-33. RDRP Field Descriptions
Field
7:0
RDRP[7:0]
Description
Reduced Drive Port P
0 Full drive strength at output.
1 Associated pin drives at about 1/3 of the full drive strength.
MC9S12XHZ512 Data Sheet, Rev. 1.06
98
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.9.5
Port P Pull Device Enable Register (PERP)
Module Base + 0x001C
7
6
5
4
3
2
1
0
PERP7
PERP6
PERP5
PERP4
PERP3
PERP2
PERP1
PERP0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-46. Port P Pull Device Enable Register (PERP)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input or
wired-or (open drain) output pins. If a pin is configured as push-pull output, the corresponding Pull Device
Enable Register bit has no effect.
Table 2-34. PERP Field Descriptions
Field
7:0
PERP[7:0]
2.3.9.6
Description
Pull Device Enable Port P
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
Port P Polarity Select Register (PPSP)
Module Base + 0x001D
7
6
5
4
3
2
1
0
PPSP7
PPSP6
PPSP5
PPSP4
PPSP3
PPSP2
PPSP1
PPSP0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-47. Port P Polarity Select Register (PPSP)
Read: Anytime. Write: Anytime.
The Port P Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port P Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
If an IIC module is enabled, a pull-up device can be activated on either the SCL or SDA pins. Pull-down
devices can not be activated on IIC pins.
Table 2-35. PPSP Field Descriptions
Field
7:0
PPSP[7:0]
Description
Polarity Select Port P
0 A pull-up device is connected to the associated port P pin.
1 A pull-down device is connected to the associated port P pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
99
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.9.7
Port P Wired-OR Mode Register (WOMP)
Module Base + 0x001E
7
6
5
4
3
WOMP7
WOMP6
WOMP5
WOMP4
0
0
0
0
R
2
0
1
0
0
WOMP2
WOMPO
W
Reset
0
0
0
0
= Reserved or Unimplemented
Figure 2-48. Port P Wired-OR Mode Register (WOMP)
Read: Anytime. Write: Anytime.
This register selects whether a port P output is configured as push-pull or wired-or. When a Wired-OR
Mode Register bit is set to 1, the corresponding output pin is driven active low only (open drain) and a
high level is not driven. A Wired-OR Mode Register bit has no effect if the corresponding pin is configured
as an input.
If IIC is enabled and the corresponding PWM channels are disabled, the pins are configured as wired-or
and the corresponding Wired-OR Mode Register bits have no effect.
Table 2-36. WOMP Field Descriptions
Field
Description
7:4
Wired-OR Mode Port P
WOMP[7:4] 0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
2
WOMP2
Wired-OR Mode Port P
0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
0
WOMP0
Wired-OR Mode Port P
0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
MC9S12XHZ512 Data Sheet, Rev. 1.06
100
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.9.8
Port P Slew Rate Register (SRRP)
Module Base + 0x003B
7
6
5
4
3
2
1
0
SRRP7
SRRP6
SRRP5
SRRP4
SRRP3
SRRP2
SRRP1
SRRP0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-49. Port P Slew Rate Register (SRRP)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PP[7:0].
Table 2-37. SRRP Field Descriptions
Field
7:0
SRRP[7:0]
Description
Slew Rate Port P
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
101
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.10
Port S
Port S is associated with the chip select 3, the serial peripheral interface (SPI) and the serial
communication interface (SCI0). Each pin is assigned to these modules according to the following
priority: CS3 > SPI/SCI1/SCI0 > general-purpose I/O.
When the SPI is enabled, the PS[7:4] pins become SS, SCK, MOSI, and MISO respectively. Refer to the
SPI block description chapter for information on enabling and disabling the SPI.
When the SCI0 receiver and transmitter are enabled, the PS[1:0] pins become TXD0 and RXD0
respectively. When the SCI1 receiver and transmitter are enabled and MODRR2 is set, the PS[3:2] pins
become TXD1 and RXD1 respectively. Refer to the SCI block description chapter for information on
enabling and disabling the SCI receiver and transmitter.
During reset, port S pins are configured as high-impedance inputs.
2.3.10.1
Port S I/O Register (PTS)
Module Base + 0x0008
7
6
5
4
3
2
1
0
PTS7
PTS6
PTS5
PTS4
PTS3
PTS2
PTS1
PTS0
SS
SCK
MOSI
MISO
TXD1
RXD1
TXD0
RXD0
0
0
R
W
SPI/
SCI1/SCI0:
Chip
Select:
Reset
CS3
0
0
0
0
0
0
= Reserved or Unimplemented
Figure 2-50. Port S I/O Register (PTS)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRSx) is set to 1 (output), a read returns the value of the I/O register
bit. If the associated data direction bit (DDRSx) is set to 0 (input), a read returns the value of the pin.
The SPI function takes precedence over the general-purpose I/O function if the SPI is enabled.
If enabled, the SCI0(1) transmitter takes precedence over the general-purpose I/O function, and the
corresponding TXD0(1) pin is configured as an output. If enabled, the SCI0(1) receiver takes precedence
over the general-purpose I/O function, and the corresponding RXD0(1) pin is configured as an input.
MC9S12XHZ512 Data Sheet, Rev. 1.06
102
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.10.2
Port S Input Register (PTIS)
Module Base + 0x0009
R
7
6
5
4
3
2
1
0
PTIS7
PTIS6
PTIS5
PTIS4
PTIS3
PTIS2
PTIS1
PTIS0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-51. Port S Input Register (PTIS)
Read: Anytime. Write: Never, writes to this register have no effect.
This register always reads back the status of the associated pins.
2.3.10.3
Port S Data Direction Register (DDRS)
Module Base + 0x000A
7
6
5
4
3
2
1
0
DDRS7
DDRS6
DDRS5
DDRS4
DDRS3
DDRS2
DDRS1
DDRS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-52. Port S Data Direction Register (DDRS)
Read: Anytime. Write: Anytime.
This register configures port pins PS[7:0] as either input or output.
When the SPI is enabled, the PS[7:4] pins become the SPI bidirectional pins. The associated Data
Direction Register bits have no effect.
When the SCI1 transmitter is enabled, the PS[3] pin becomes the TXD1 output pin and the associated Data
Direction Register bit has no effect. When the SCI1 receiver is enabled, the PS[2] pin becomes the RXD1
input pin and the associated Data Direction Register bit has no effect.
When the SCI0 transmitter is enabled, the PS[1] pin becomes the TXD0 output pin and the associated Data
Direction Register bit has no effect. When the SCI0 receiver is enabled, the PS[0] pin becomes the RXD0
input pin and the associated Data Direction Register bit has no effect.
If the SPI, SCI1 and SCI0 functions are disabled, the corresponding Data Direction Register bit reverts to
control the I/O direction of the associated pin.
Table 2-38. DDRS Field Descriptions
Field
7:0
DDRS[7:0]
Description
Data Direction Port S
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
103
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.10.4
Port S Reduced Drive Register (RDRS)
Module Base + 0x000B
7
6
5
4
3
2
1
0
RDRS7
RDRS6
RDRS5
RDRS4
RDRS3
RDRS2
RDRS1
RDRS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-53. Port S Reduced Drive Register (RDRS)
Read: Anytime. Write: Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
Table 2-39. RDRS Field Descriptions
Field
7:0
RDRS[7:0]
2.3.10.5
Description
Reduced Drive Port S
0 Full drive strength at output.
1 Associated pin drives at about 1/3 of the full drive strength.
Port S Pull Device Enable Register (PERS)
Module Base + 0x000C
7
6
5
4
3
2
1
0
PERS7
PERS6
PERS5
PERS4
PERS3
PERS2
PERS1
PERS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-54. Port S Pull Device Enable Register (PERS)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input or
wired-or (open drain) output pins. If a pin is configured as push-pull output, the corresponding Pull Device
Enable Register bit has no effect.
Table 2-40. PERS Field Descriptions
Field
7:0
PERS[7:0]
Description
Pull Device Enable Port S
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
104
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.10.6
Port S Polarity Select Register (PPSS)
Module Base + 0x000D
7
6
5
4
3
2
1
0
PPSS7
PPSS6
PPSS5
PPSS4
PPSS3
PPSS2
PPSS1
PPSS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-55. Port S Polarity Select Register (PPSS)
Read: Anytime. Write: Anytime.
The Port S Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port S Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 2-41. PPSS Field Descriptions
Field
Description
7:0
PPSS[7:0]
Pull Select Port S
0 A pull-up device is connected to the associated port S pin.
1 A pull-down device is connected to the associated port S pin.
2.3.10.7
Port S Wired-OR Mode Register (WOMS)
Module Base + 0x000E
7
6
5
4
3
2
1
0
WOMS7
WOMS6
WOMS5
WOMS4
WOMS3
WOMS2
WOMS1
WOMS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-56. Port S Wired-OR Mode Register (WOMS)
Read: Anytime. Write: Anytime.
This register selects whether a port S output is configured as push-pull or wired-or. When a Wired-OR
Mode Register bit is set to 1, the corresponding output pin is driven active low only (open drain) and a
high level is not driven. A Wired-OR Mode Register bit has no effect if the corresponding pin is configured
as an input.
Table 2-42. WOMS Field Descriptions
Field
Description
7:0
Wired-OR Mode Port S
WOMS[7:0] 0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
105
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.10.8
Port S Slew Rate Register (SRRS)
Module Base + 0x003B
7
6
5
4
3
2
1
0
SRRS7
SRRS6
SRRS5
SRRS4
SRRS3
SRRS2
SRRS1
SRRS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-57. Port S Slew Rate Register (SRRS)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PS[7:0].
Table 2-43. SRRS Field Descriptions
Field
7:0
SRRS[7:0]
Description
Slew Rate Port S
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
MC9S12XHZ512 Data Sheet, Rev. 1.06
106
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.11
Port T
Port T is associated with the 8-channel enhanced capture timer (ECT), the Inter-IC (IIC0 and IIC1)
modules and the liquid crystal display (LCD) driver. Each pin is assigned to these modules according to
the following priority: LCD Driver > IIC1/IIC0 > ECT > general-purpose I/O.
When the IIC1 module is enabled and MODRR1 is set, PT[7:6] pins become SCL1 and SDA1 pins
respectively. When the IIC0 module is enabled and MODRR0 is set, PT[5:4] pins become SCL0 and
SDA0 respectively. Refer to the IIC block description chapter for information on enabling and disabling
the IIC bus.
If the corresponding LCD frontplane drivers are enabled (and LCD module is enabled), the FP[27:24]
outputs of the LCD module are available on port T pins PT[3:0].
If the corresponding LCD frontplane drivers are disabled (or LCD module is disabled) and the ECT is
enabled, the timer channels configured for output compare are available on port T pins PT[3:0].
Refer to the LCD block description chapter for information on enabling and disabling the LCD and its
frontplane drivers.Refer to the ECT block description chapter for information on enabling and disabling
the ECT module.
During reset, port T pins are configured as inputs with pull down.
2.3.11.1
Port T I/O Register (PTT)
Module Base + 0x0000
7
6
5
4
3
2
1
0
PTT7
PTT6
PTT5
PTT4
PTT3
PTT2
PTT1
PTT0
ECT:
OC7
OC6
OC5
OC4
OC3
OC2
OC1
OC0
IIC1/IIC0:
SCL1
SDA1
SCL0
SDA0
1
1
1
1
0
0
0
0
R
W
LCD:
Reset
0
0
0
0
Figure 2-58. Port T I/O Register (PTT)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRTx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRTx) is set to 0 (input) and the LCD frontplane driver is enabled
(and LCD module is enabled), the associated I/O register bit (PTTx) reads “1”.
If the associated data direction bit (DDRTx) is set to 0 (input) and the LCD frontplane driver is disabled
(or LCD module is disabled), a read returns the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
107
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.11.2
Port T Input Register (PTIT)
Module Base + 0x0001
R
7
6
5
4
3
2
1
0
PTIT7
PTIT6
PTIT5
PTIT4
PTIT3
PTIT2
PTIT1
PTIT0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-59. Port T Input Register (PTIT)
Read: Anytime. Write: Never, writes to this register have no effect.
If the LCD frontplane driver of an associated I/O pin is enabled (and LCD module is enabled), a read
returns a 1.
If the LCD frontplane driver of the associated I/O pin is disabled (or LCD module is disabled), a read
returns the status of the associated pin.
2.3.11.3
Port T Data Direction Register (DDRT)
Module Base + 0x0002
7
6
5
4
3
2
1
0
DDRT7
DDRT6
DDRT5
DDRT4
DDRT3
DDRT2
DDRT1
DDRT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-60. Port T Data Direction Register (DDRT)
Read: Anytime. Write: Anytime.
This register configures port pins PT[7:0] as either input or output.
If a LCD frontplane driver is enabled (and LCD module is enabled), it outputs an analog signal to the
corresponding pin and the associated Data Direction Register bit has no effect. If a LCD frontplane driver
is disabled (or LCD module is disabled), the corresponding Data Direction Register bit reverts to control
the I/O direction of the associated pin.
If the ECT module is enabled, each port pin configured for output compare is forced to be an output and
the associated Data Direction Register bit has no effect. If the associated timer output compare is disabled,
the corresponding Data Direction Register bit reverts to control the I/O direction of the associated pin.
If the ECT module is enabled, each port pin configured as an input capture has the corresponding Data
Direction Register bit controlling the I/O direction of the associated pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
108
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-44. DDRT Field Descriptions
Field
7:0
DDRT[7:0]
2.3.11.4
Description
Data Direction Port T
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Port T Reduced Drive Register (RDRT)
Module Base + 0x0003
7
6
5
4
3
2
1
0
RDRT7
RDRT6
RDRT5
RDRT4
RDRT3
RDRT2
RDRT1
RDRT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-61. Port T Reduced Drive Register (RDRT)
Read: Anytime. Write: Anytime.
This register configures the drive strength of configured output pins as either full or reduced. If a pin is
configured as input, the corresponding Reduced Drive Register bit has no effect.
Table 2-45. RDRT Field Descriptions
Field
7:0
RDRT[7:0]
Description
Reduced Drive Port T
0 Full drive strength at output.
1 Associated pin drives at about 1/3 of the full drive strength.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
109
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.11.5
Port T Pull Device Enable Register (PERT)
Module Base + 0x0004
7
6
5
4
3
2
1
0
PERT7
PERT6
PERT5
PERT4
PERT3
PERT2
PERT1
PERT0
0
0
0
0
1
1
1
1
R
W
Reset
Figure 2-62. Port T Pull Device Enable Register (PERT)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
For port pins PT[7:4], a pull-up device can be activated on wired-or (open drain) output pins. If the pin is
configured as push-pull output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-46. PERT Field Descriptions
Field
7:0
PERT[7:0]
2.3.11.6
Description
Pull Device Enable Port T
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
Port T Polarity Select Register (PPST)
Module Base + 0x0005
7
6
5
4
3
2
1
0
PPST7
PPST6
PPST5
PPST4
PPST3
PPST2
PPST1
PPST0
0
0
0
0
1
1
1
1
R
W
Reset
Figure 2-63. Port T Polarity Select Register (PPST)
Read: Anytime. Write: Anytime.
The Port T Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port T Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
If an IIC module is enabled, a pull-up device can be activated on either the SCL or SDA pins. Pull-down
devices can not be activated on IIC pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
110
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-47. PPST Field Descriptions
Field
Description
7:0
PPST[7:0]
Pull Select Port T
0 A pull-up device is connected to the associated port T pin.
1 A pull-down device is connected to the associated port T pin.
2.3.11.7
Port T Wired-OR Mode Register (WOMT)
Module Base + 0x003B
7
6
5
4
3
WOMT7
WOMT6
WOMT5
WOMT4
0
0
0
0
R
2
1
0
MODRR2
MODRR1
MODRR0
0
0
0
0
W
Reset
0
= Reserved or Unimplemented
Figure 2-64. Port T Wired-OR Mode Register (WOMT)
Read: Anytime. Write: Anytime.
This register selects whether a port T output is configured as push-pull or wired-or. When a Wired-OR
Mode Register bit is set to 1, the corresponding output pin is driven active low only (open drain) and a
high level is not driven. A Wired-OR Mode Register bit has no effect if the corresponding pin is configured
as an input.
If IIC is enabled, the pins are configured as wired-or and the corresponding Wired-OR Mode Register bits
have no effect.
This register also configures the re-routing of IIC0, IIC1 and SCI1 on alternative ports.
Table 2-48. WOMT Field Descriptions
Field
Description
7:4
Wired-OR Mode Port T
WOMT[7:4] 0 Output buffers operate as push-pull outputs.
1 Output buffers operate as open-drain outputs.
2
MODRR2
SCI1 Routing Bit — See Table 2-49..
1
MODRR1
IIC1 Routing Bit — See Table 2-50..
0
MODRR0
IIC0 Routing Bit — See Table 2-51..
Table 2-49. SCI1 Routing
MODRR[2]
TXD1
RXD1
0
PP0
PP2
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
111
Chapter 2 Port Integration Module (S12XHZPIMV1)
Table 2-49. SCI1 Routing
MODRR[2]
TXD1
RXD1
1
PS3
PS2
Table 2-50. IIC1 Routing
MODRR[1]
SDA1
SCL1
0
PP6
PP7
1
PT6
PT7
Table 2-51. IIC0 Routing
2.3.11.8
MODRR[0]
SDA0
SCL0
0
PP4
PP5
1
PT4
PT5
Port T Slew Rate Register (SRRT)
Module Base + 0x003B
7
6
5
4
3
2
1
0
SRRT7
SRRT6
SRRT5
SRRT4
SRRT3
SRRT2
SRRT1
SRRT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-65. Port T Slew Rate Register (SRRT)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PT[7:0].
Table 2-52. SRRT Field Descriptions
Field
7:0
SRRT[7:0]
Description
Slew Rate Port T
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
MC9S12XHZ512 Data Sheet, Rev. 1.06
112
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.12
Port U
Port U is associated with the stepper stall detect (SSD1 and SSD0) and motor controller (MC1 and MC0)
modules. Each pin is assigned to these modules according to the following priority: SSD1/SSD0 >
MC1/MC0 > general-purpose I/O.
If SSD1 module is enabled, the PU[7:4] pins are controlled by the SSD1 module. If SSD1 module is
disabled, the PU[7:4] pins are controlled by the motor control PWM channels 3 and 2 (MC1).
If SSD0 module is enabled, the PU[3:0] pins are controlled by the SSD0 module. If SSD0 module is
disabled, the PU[3:0] pins are controlled by the motor control PWM channels 1 and 0 (MC0).
Refer to the SSD and MC block description chapters for information on enabling and disabling the SSD
module and the motor control PWM channels respectively.
During reset, port U pins are configured as high-impedance inputs.
2.3.12.1
Port U I/O Register (PTU)
Module Base + 0x0038
7
6
5
4
3
2
1
0
PTU7
PTU6
PTU5
PTU4
PTU3
PTU2
PTU1
PTU0
MC:
M1C1P
M1C1M
M1COP
M1COM
M0C1P
M0C1M
M0C0P
M0C0M
SSD1/
SSD0:
M1SINP
M1SINM
M1COSP
M1COSM
M0SINP
M0SINM
M1COSP
M0COSM
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-66. Port U I/O Register (PTU)
Read: Anytime. Write: Anytime.
If the associated data direction bit (DDRUx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRUx) is set to 0 (input) and the slew rate is enabled, the associated
I/O register bit (PTUx) reads “1”.
If the associated data direction bit (DDRUx) is set to 0 (input) and the slew rate is disabled, a read returns
the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
113
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.12.2
Port U Input Register (PTIU)
Module Base + 0x0039
R
7
6
5
4
3
2
1
0
PTIU7
PTIU6
PTIU5
PTIU4
PTIU3
PTIU2
PTIU1
PTIU0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-67. Port U Input Register (PTIU)
Read: Anytime. Write: Never, writes to this register have no effect.
If the associated slew rate control is enabled (digital input buffer is disabled), a read returns a “1”. If the
associated slew rate control is disabled (digital input buffer is enabled), a read returns the status of the
associated pin.
2.3.12.3
Port U Data Direction Register (DDRU)
Module Base + 0x003A
7
6
5
4
3
2
1
0
DDRU7
DDRU6
DDRU5
DDRU4
DDRU3
DDRU2
DDRU1
DDRU0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-68. Port U Data Direction Register (DDRU)
Read: Anytime. Write: Anytime.
This register configures port pins PU[7:0] as either input or output.
When enabled, the SSD or MC modules force the I/O state to be an output for each associated pin and the
associated Data Direction Register bit has no effect. If the SSD and MC modules are disabled, the
corresponding Data Direction Register bits revert to control the I/O direction of the associated pins.
Table 2-53. DDRU Field Descriptions
Field
7:0
DDRU[7:0]
Description
Data Direction Port U
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
114
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.12.4
Port U Slew Rate Register (SRRU)
Module Base + 0x003B
7
6
5
4
3
2
1
0
SRRU7
SRRU6
SRRU5
SRRU4
SRRU3
SRRU2
SRRU1
SRRU0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-69. Port U Slew Rate Register (SRRU)
Read: Anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PU[7:0].
Table 2-54. SRRU Field Descriptions
Field
7:0
SRRU[7:0]
2.3.12.5
Description
Slew Rate Port U
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
Port U Pull Device Enable Register (PERU)
Module Base + 0x003C
7
6
5
4
3
2
1
0
PERU7
PERU6
PERU5
PERU4
PERU3
PERU2
PERU1
PERU0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-70. Port U Pull Device Enable Register (PERU)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-55. PERU Field Descriptions
Field
7:0
PERU[7:0]
Description
Pull Device Enable Port U
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
115
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.12.6
Port U Polarity Select Register (PPSU)
Module Base + 0x003D
7
6
5
4
3
2
1
0
PPSU7
PPSU6
PPSU5
PPSU4
PPSU3
PPSU2
PPSU1
PPSU0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-71. Port U Polarity Select Register (PPSU)
Read: Anytime. Write: Anytime.
The Port U Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port U Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 2-56. PPSU Field Descriptions
Field
7:0
PPSU[7:0]
Description
Pull Select Port U
0 A pull-up device is connected to the associated port U pin.
1 A pull-down device is connected to the associated port U pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
116
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.13
Port V
Port V is associated with the stepper stall detect (SSD3 and SSD2) and motor controller (MC3 and MC2)
modules. Each pin is assigned to these modules according to the following priority: SSD3/SSD2 >
MC3/MC2 > general-purpose I/O.
If SSD3 module is enabled, the PV[7:4] pins are controlled by the SSD3 module. If SSD3 module is
disabled, the PV[7:4] pins are controlled by the motor control PWM channels 7 and 6 (MC3).
If SSD2 module is enabled, the PV[3:0] pins are controlled by the SSD2 module. If SSD2 module is
disabled, the PV[3:0] pins are controlled by the motor control PWM channels 5 and 4 (MC2).
Refer to the SSD and MC block description chapters for information on enabling and disabling the SSD
module and the motor control PWM channels respectively.
During reset, port V pins are configured as high-impedance inputs.
2.3.13.1
Port V I/O Register (PTV)
Module Base + 0x0040
7
6
5
4
3
2
1
0
PTV7
PTV6
PTV5
PTV4
PTV3
PTV2
PTV1
PTV0
MC:
M3C1P
M3C1M
M3C0P
M3C0M
M2C1P
M2C1M
M2C0P
M2C0M
SSD3/
SSD2
M3SINP
M3SINM
M3COSP
M3COSM
M2SINP
M2SINM
M2COSP
M2COSM
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-72. Port V I/O Register (PTV)
Read: Anytime. Write: anytime.
If the associated data direction bit (DDRVx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRVx) is set to 0 (input) and the slew rate is enabled, the associated
I/O register bit (PTVx) reads “1”.
If the associated data direction bit (DDRVx) is set to 0 (input) and the slew rate is disabled, a read returns
the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
117
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.13.2
Port V Input Register (PTIV)
Module Base + 0x0041
R
7
6
5
4
3
2
1
0
PTIV7
PTIV6
PTIV5
PTIV4
PTIV3
PTIV2
PTIV1
PTIV0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-73. Port V Input Register (PTIV)
Read: Anytime. Write: Never, writes to this register have no effect.
If the associated slew rate control is enabled (digital input buffer is disabled), a read returns a “1”. If the
associated slew rate control is disabled (digital input buffer is enabled), a read returns the status of the
associated pin.
2.3.13.3
Port V Data Direction Register (DDRV)
Module Base + 0x0042
7
6
5
4
3
2
1
0
DDRV7
DDRV6
DDRV5
DDRV4
DDRV3
DDRV2
DDRV1
DDRV0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-74. Port V Data Direction Register (DDRV)
Read: Anytime. Write: Anytime.
This register configures port pins PV[7:0] as either input or output.
When enabled, the SSD or MC modules force the I/O state to be an output for each associated pin and the
associated Data Direction Register bit has no effect. If the SSD and MC modules are disabled, the
corresponding Data Direction Register bits revert to control the I/O direction of the associated pins.
Table 2-57. DDRV Field Descriptions
Field
7:0
DDRV[7:0]
Description
Data Direction Port V
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
118
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.13.4
Port V Slew Rate Register (SRRV)
Module Base + 0x0043
7
6
5
4
3
2
1
0
SRRV7
SRRV6
SRRV5
SRRV4
SRRV3
SRRV2
SRRV1
SRRV0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-75. Port V Slew Rate Register (SRRV)
Read: anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PV[7:0].
Table 2-58. SRRV Field Descriptions
Field
7:0
SRRV[7:0]
2.3.13.5
Description
Slew Rate Port V
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
Port V Pull Device Enable Register (PERV)
Module Base + 0x0044
7
6
5
4
3
2
1
0
PERV7
PERV6
PERV5
PERV4
PERV3
PERV2
PERV1
PERV0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-76. Port V Pull Device Enable Register (PERV)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-59. PERV Field Descriptions
Field
7:0
PERV[7:0]
Description
Pull Device Enable Port V
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
119
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.13.6
Port V Polarity Select Register (PPSV)
Module Base + 0x0045
7
6
5
4
3
2
1
0
PPSV7
PPSV6
PPSV5
PPSV4
PPSV3
PPSV2
PPSV1
PPSV0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-77. Port V Polarity Select Register (PPSV)
Read: Anytime. Write: Anytime.
The Port V Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port V Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 2-60. PPSV Field Descriptions
Field
7:0
PPSV[7:0]
Description
Pull Select Port V
0 A pull-up device is connected to the associated port V pin.
1 A pull-down device is connected to the associated port V pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
120
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.14
Port W
Port W is associated with the stepper stall detect (SSD5 and SSD4) and motor controller (MC5 and MC4)
modules. Each pin is assigned to these modules according to the following priority: SSD5/SSD4 >
MC5/MC4 > general-purpose I/O.
If SSD5 module is enabled, the PW[7:4] pins are controlled by the SSD5 module. If SSD5 module is
disabled, the PW[7:4] pins are controlled by the motor control PWM channels 11 and 10 (MC5).
If SSD4 module is enabled, the PW[3:0] pins are controlled by the SSD4 module. If SSD4 module is
disabled, the PW[3:0] pins are controlled by the motor control PWM channels 9 and 8 (MC4).
Refer to the SSD and MC block description chapters for information on enabling and disabling the SSD
module and the motor control PWM channels respectively.
During reset, port W pins are configured as high-impedance inputs.
2.3.14.1
Port W I/O Register (PTW)
Module Base + 0x0040
7
6
5
4
3
2
1
0
PTW7
PTW6
PTW5
PTW4
PTW3
PTW2
PTW1
PTW0
MC:
M5C1P
M3C1M
M5C0P
M5C0M
M4C1P
M4C1M
M4C0P
M4C0M
SSD5/
SSD4
M5SINP
M3SINM
M5COSP
M5COSM
M4SINP
M4SINM
M4COSP
M4COSM
Reset
0
0
0
0
0
0
0
0
R
W
Figure 2-78. Port W I/O Register (PTW)
Read: Anytime. Write: anytime.
If the associated data direction bit (DDRWx) is set to 1 (output), a read returns the value of the I/O register
bit.
If the associated data direction bit (DDRWx) is set to 0 (input) and the slew rate is enabled, the associated
I/O register bit (PTWx) reads “1”.
If the associated data direction bit (DDRWx) is set to 0 (input) and the slew rate is disabled, a read returns
the value of the pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
121
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.14.2
Port W Input Register (PTIW)
Module Base + 0x0041
R
7
6
5
4
3
2
1
0
PTIW7
PTIW6
PTIW5
PTIW4
PTIW3
PTIW2
PTIW1
PTIW0
u
u
u
u
u
u
u
u
W
Reset
= Reserved or Unimplemented
u = Unaffected by reset
Figure 2-79. Port W Input Register (PTIW)
Read: Anytime. Write: Never, writes to this register have no effect.
If the associated slew rate control is enabled (digital input buffer is disabled), a read returns a “1”. If the
associated slew rate control is disabled (digital input buffer is enabled), a read returns the status of the
associated pin.
2.3.14.3
Port W Data Direction Register (DDRW)
Module Base + 0x0042
7
6
5
4
3
2
1
0
DDRW7
DDRW6
DDRW5
DDRW4
DDRW3
DDRW2
DDRW1
DDRW0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-80. Port W Data Direction Register (DDRW)
Read: Anytime. Write: Anytime.
This register configures port pins PW[7:0] as either input or output.
When enabled, the SSD or MC modules force the I/O state to be an output for each associated pin and the
associated Data Direction Register bit has no effect. If the SSD and MC modules are disabled, the
corresponding Data Direction Register bits revert to control the I/O direction of the associated pins.
Table 2-61. DDRW Field Descriptions
Field
7:0
DDRW[7:0]
Description
Data Direction Port W
0 Associated pin is configured as input.
1 Associated pin is configured as output.
MC9S12XHZ512 Data Sheet, Rev. 1.06
122
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.14.4
Port W Slew Rate Register (SRRW)
Module Base + 0x0043
7
6
5
4
3
2
1
0
SRRW7
SRRW6
SRRW5
SRRW4
SRRW3
SRRW2
SRRW1
SRRW0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-81. Port W Slew Rate Register (SRRW)
Read: anytime. Write: Anytime.
This register enables the slew rate control and disables the digital input buffer for port pins PW[7:0].
Table 2-62. SRRW Field Descriptions
Field
7:0
SRRW[7:0]
2.3.14.5
Description
Slew Rate Port W
0 Disables slew rate control and enables digital input buffer.
1 Enables slew rate control and disables digital input buffer.
Port W Pull Device Enable Register (PERW)
Module Base + 0x0044
7
6
5
4
3
2
1
0
PERW7
PERW6
PERW5
PERW4
PERW3
PERW2
PERW1
PERW0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-82. Port W Pull Device Enable Register (PERW)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 2-63. PERW Field Descriptions
Field
7:0
PERW[7:0]
Description
Pull Device Enable Port W
0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
123
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.3.14.6
Port W Polarity Select Register (PPSW)
Module Base + 0x0045
7
6
5
4
3
2
1
0
PPSW7
PPSW6
PPSW5
PPSW4
PPSW3
PPSW2
PPSW1
PPSW0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-83. Port W Polarity Select Register (PPSW)
Read: Anytime. Write: Anytime.
The Port W Polarity Select Register selects whether a pull-down or a pull-up device is connected to the
pin. The Port W Polarity Select Register is effective only when the corresponding Data Direction Register
bit is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 2-64. PPSW Field Descriptions
Field
7:0
PPSW[7:0]
Description
Pull Select Port W
0 A pull-up device is connected to the associated port W pin.
1 A pull-down device is connected to the associated port W pin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
124
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.4
Functional Description
Each pin except PE0, PE1, and BKGD can act as general-purpose I/O. In addition the pin can act as an
output from a peripheral module or an input to a peripheral module.
A set of configuration registers is common to all ports. All registers can be written at any time, however a
specific configuration might not become active.
Example: Selecting a pull-up resistor. This resistor does not become active while the port is used
as a push-pull output.
Table 2-65. Register Availability per Port1
1
Port
Data
Data
Direction
Input
Reduced
Drive
Pull
Enable
Polarity
Select
Wired-OR
Interrupt
Slew Rate
Mode
Enable
A
yes
yes
—
yes
yes
—
—
B
yes
yes
—
—
C
yes
yes
—
D
yes
yes
—
E
yes
yes
K
yes
AD
L
yes
Interrupt
Flag
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
yes
—
—
—
—
—
yes
yes
yes
yes
yes
yes
—
—
yes
yes
yes
yes
yes
yes
yes
yes
—
yes
—
—
M
yes
yes
yes
yes
yes
yes
yes
yes
—
—
P
yes
yes
yes
yes
yes
yes
yes
yes
—
—
S
yes
yes
yes
yes
yes
yes
yes
yes
—
—
T
yes
yes
yes
yes
yes
yes
yes
yes
—
—
U
yes
yes
yes
—
yes
yes
—
yes
—
—
V
yes
yes
yes
—
yes
yes
—
yes
—
—
W
yes
yes
yes
—
yes
yes
—
yes
—
—
Each cell represents one register with individual configuration bits
2.4.1
I/O Register
The I/O Register holds the value driven out to the pin if the port is used as a general-purpose I/O. Writing
to the I/O Register only has an effect on the pin if the port is used as general-purpose output.
When reading the I/O Register, the value of each pin is returned if the corresponding Data Direction
Register bit is set to 0 (pin configured as input). If the data direction register bits is set to 1, the content of
the I/O Register bit is returned. This is independent of any other configuration (Figure 2-84).
Due to internal synchronization circuits, it can take up to 2 bus cycles until the correct value is read on the
I/O Register when changing the data direction register.
2.4.2
Input Register
The Input Register is a read-only register and generally returns the value of the pin (Figure 2-84).It can be
used to detect overload or short circuit conditions.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
125
Chapter 2 Port Integration Module (S12XHZPIMV1)
Due to internal synchronization circuits, it can take up to 2 bus cycles until the correct value is read on the
Input Register when changing the Data Direction Register.
2.4.3
Data Direction Register
The Data Direction Register defines whether the pin is used as an input or an output.
. A Data Direction Register bit set to 0 configures the pin as an input. A Data Direction Register bit set to
1 configures the pin as an output. If a peripheral module controls the pin the contents of the data direction
register is ignored (Figure 2-84).
PTIx
0
1
PTx
PAD
0
1
DDRx
0
1
Digital
Module
data out
output enable
module enable
Figure 2-84. Illustration of I/O Pin Functionality
Figure 2-85 shows the state of digital inputs and outputs when an analog module drives the port. When the
analog module is enabled all associated digital output ports are disabled and all associated digital input
ports read “1”t.
1
Digital
Input
1
0
Module
Enable
Analog
Module
Digital
Output
Analog
Output
0
PAD
1
PIM Boundary
Figure 2-85. Digital Ports and Analog Module
MC9S12XHZ512 Data Sheet, Rev. 1.06
126
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.4.4
Reduced Drive Register
If the port is used as an output the Reduced Drive Register allows the configuration of the drive strength.
2.4.5
Pull Device Enable Register
The Pull Device Enable Register turns on a pull-up or pull-down device. The pull device becomes active
only if the pin is used as an input or as a wired-or output.
2.4.6
Polarity Select Register
The Polarity Select Register selects either a pull-up or pull-down device if enabled. The pull device
becomes active only if the pin is used as an input or as a wired-or output.
2.4.7
Pin Configuration Summary
The following table summarizes the effect of various configuration in the Data Direction (DDR),
Input/Output (I/O), reduced drive (RDR), Pull Enable (PE), Pull Select (PS) and Interrupt Enable (IE)
register bits. The PS configuration bit is used for two purposes:
1. Configure the sensitive interrupt edge (rising or falling), if interrupt is enabled.
2. Select either a pull-up or pull-down device if PE is set to “1”.
Table 2-66. Pin Configuration Summary
1
2
DDR
IO
RDR
PE
PS
IE1
Function2
Pull Device
Interrupt
0
X
X
0
X
0
Input
Disabled
Disabled
0
X
X
1
0
0
Input
Pull Up
Disabled
0
X
X
1
1
0
Input
Pull Down
Disabled
0
X
X
0
0
1
Input
Disabled
Falling Edge
0
X
X
0
1
1
Input
Disabled
Rising Edge
0
X
X
1
0
1
Input
Pull Up
Falling Edge
0
X
X
1
1
1
Input
Pull Down
Rising Edge
1
0
0
X
X
0
Output to 0, Full Drive
Disabled
Disabled
1
1
0
X
X
0
Output to 1, Full Drive
Disabled
Disabled
1
0
1
X
X
0
Output to 0, Reduced Drive
Disabled
Disabled
1
1
1
X
X
0
Output to 1, Reduced Drive
Disabled
Disabled
1
0
0
X
0
1
Output to 0, Full Drive
Disabled
Falling Edge
1
1
0
X
1
1
Output to 1, Full Drive
Disabled
Rising Edge
1
0
1
X
0
1
Output to 0, Reduced Drive
Disabled
Falling Edge
1
1
1
X
1
1
Output to 1, Reduced Drive
Disabled
Rising Edge
Applicable only on Port AD.
Digital outputs are disabled and digital input logic is forced to “1” when an analog module associated with the port is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
127
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.5
Resets
The reset values of all registers are given in the register description in Section 2.3, “Memory Map and
Register Definition”.
All ports start up as general-purpose inputs on reset.
2.5.1
Reset Initialization
All registers including the data registers get set/reset asynchronously. Table 2-67 summarizes the port
properties after reset initialization.
P
Table 2-67. Port Reset State Summary
Reset States
Port
1
Data
Direction
Pull Mode
Reduced
Drive
Slew Rate
Wired-OR
Mode
Interrupt
A
Input
Pull Down
Disabled
Disabled
N/A
N/A
B
Input
Pull Down
Disabled
Disabled
N/A
N/A
C
Input
Hi-z
Disabled
Disabled
N/A
N/A
D
Input
Hi-z
Disabled
Disabled
N/A
N/A
Disabled
Disabled
N/A
N/A
1
E
Input
Pull Down
K
Input
Pull Down
Disabled
Disabled
N/A
N/A
AD
Input
Hi-z
Disabled
N/A
N/A
Disabled
L
Input
Pull Down
Disabled
Disabled
N/A
N/A
M
Input
Hi-z
Disabled
Disabled
Disabled
N/A
P
Input
Hi-z
Disabled
Disabled
Disabled
N/A
S
Input
Hi-z
Disabled
Disabled
Disabled
N/A
T[7:4]
Input
Hi-z
Disabled
Disabled
Disabled
N/A
T[3:0]
Input
Pull Down
Disabled
Disabled
Disabled
N/A
U
Input
Hi-z
Disabled
Disabled
N/A
N/A
V
Input
Hi-z
Disabled
Disabled
N/A
N/A
W
Input
Hi-z
Disabled
Disabled
N/A
N/A
PE[1:0] pins have pull-ups instead of pull-downs.
MC9S12XHZ512 Data Sheet, Rev. 1.06
128
Freescale Semiconductor
Chapter 2 Port Integration Module (S12XHZPIMV1)
2.6
2.6.1
Interrupts
General
Port AD generates an edge sensitive interrupt if enabled. It offers eight I/O pins with edge triggered
interrupt capability in wired-or fashion. The interrupt enable as well as the sensitivity to rising or falling
edges can be individually configured on per pin basis. All eight bits/pins share the same interrupt vector.
Interrupts can be used with the pins configured as inputs (with the corresponding ATDDIEN1 bit set to
1)or outputs.
An interrupt is generated when a bit in the port interrupt flag register and its corresponding port interrupt
enable bit are both set. This external interrupt feature is capable to wake up the CPU when it is in stop or
wait mode.
A digital filter on each pin prevents pulses (Figure 2-87) shorter than a specified time from generating an
interrupt. The minimum time varies over process conditions, temperature and voltage (Figure 2-86 and
Table 2-68).
Glitch, filtered out, no interrupt flag set
Valid pulse, interrupt flag set
tifmin
tifmax
Figure 2-86. Interrupt Glitch Filter on Port AD (PPS = 0)
Table 2-68. Pulse Detection Criteria
Mode
Pulse
STOP1
STOP
Unit
Ignored
Uncertain
Valid
1
tpulse <= 3
3 < tpulse
<4
tpulse >= 4
Bus Clock
Bus Clock
Bus Clock
Unit
tpulse <= 3.2
3.2 < tpulse
< 10
tpulse >= 10
µs
µs
µs
These values include the spread of the oscillator frequency over temperature,
voltage and process.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
129
Chapter 2 Port Integration Module (S12XHZPIMV1)
tpulse
Figure 2-87. Pulse Illustration
A valid edge on an input is detected if 4 consecutive samples of a passive level are followed by 4
consecutive samples of an active level directly or indirectly
The filters are continuously clocked by the bus clock in RUN and WAIT mode. In STOP mode the clock
is generated by a single RC oscillator in the port integration module. To maximize current saving the RC
oscillator runs only if the following condition is true on any pin:Sample count <= 4 and port interrupt
enabled (PIE=1) and port interrupt flag not set (PIF=0).
2.6.2
Interrupt Sources
Table 2-69. Port Integration Module Interrupt Sources
Interrupt
Source
Interrupt
Flag
Local
Enable
Global (CCR)
Mask
Port AD
PIFAD[7:0]
PIEAD[7:0]
I Bit
NOTE
Vector addresses and their relative interrupt priority are determined at the
MCU level.
2.6.3
Operation in Stop Mode
All clocks are stopped in STOP mode. The port integration module has asynchronous paths on port AD to
generate wake-up interrupts from stop mode. For other sources of external interrupts refer to the respective
block description chapters.
MC9S12XHZ512 Data Sheet, Rev. 1.06
130
Freescale Semiconductor
Chapter 3
512 Kbyte Flash Module (S12XFTX512K4V3)
3.1
Introduction
This document describes the FTX512K4 module that includes a 512 Kbyte Flash (nonvolatile) memory.
The Flash memory may be read as either bytes, aligned words or misaligned words. Read access time is
one bus cycle for bytes and aligned words, and two bus cycles for misaligned words.
The Flash memory is ideal for program and data storage for single-supply applications allowing for field
reprogramming without requiring external voltage sources for program or erase. Program and erase
functions are controlled by a command driven interface. The Flash module supports both block erase and
sector erase. An erased bit reads 1 and a programmed bit reads 0. The high voltage required to program
and erase the Flash memory is generated internally. It is not possible to read from a Flash block while it is
being erased or programmed.
CAUTION
A Flash word must be in the erased state before being programmed.
Cumulative programming of bits within a Flash word is not allowed.
3.1.1
Glossary
Command Write Sequence — A three-step MCU instruction sequence to execute built-in algorithms
(including program and erase) on the Flash memory.
Multiple-Input Signature Register (MISR) — A Multiple-Input Signature Register is an output
response analyzer implemented using a linear feedback shift-register (LFSR). A 16-bit MISR is used to
compress data and generate a signature that is particular to the data read from a Flash block.
3.1.2
•
•
•
•
•
•
•
•
Features
512 Kbytes of Flash memory comprised of four 128 Kbyte blocks with each block divided into
128 sectors of 1024 bytes
Automated program and erase algorithm
Interrupts on Flash command completion, command buffer empty
Fast sector erase and word program operation
2-stage command pipeline for faster multi-word program times
Sector erase abort feature for critical interrupt response
Flexible protection scheme to prevent accidental program or erase
Single power supply for all Flash operations including program and erase
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
131
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
•
•
3.1.3
Security feature to prevent unauthorized access to the Flash memory
Code integrity check using built-in data compression
Modes of Operation
Program, erase, erase verify, and data compress operations (please refer to Section 3.4.1, “Flash Command
Operations” for details).
3.1.4
Block Diagram
A block diagram of the Flash module is shown in Figure 3-1.
MC9S12XHZ512 Data Sheet, Rev. 1.06
132
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
FTX512K4
Flash Block 0
64K * 16 Bits
sector 0
sector 1
Flash
Interface
Command
Interrupt
Request
sector 127
Command Pipeline
cmd2
addr2
data2_0
data2_1
data2_2
data2_3
cmd1
addr1
data1_0
data1_1
data1_2
data1_3
Flash Block 1
64K * 16 Bits
sector 0
sector 1
Registers
Protection
sector 127
Flash Block 2
64K * 16 Bits
sector 0
sector 1
Security
sector 127
Oscillator
Clock
Clock
Divider FCLK
Flash Block 3
64K * 16 Bits
sector 0
sector 1
sector 127
Figure 3-1. FTX512K4 Block Diagram
3.2
External Signal Description
The Flash module contains no signals that connect off-chip.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
133
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3
Memory Map and Register Definition
This section describes the memory map and registers for the Flash module.
3.3.1
Module Memory Map
The Flash memory map is shown in Figure 3-2. The HCS12X architecture places the Flash memory
addresses between global addresses 0x78_0000 and 0x7F_FFFF. The FPROT register, described in
Section 3.3.2.5, “Flash Protection Register (FPROT)”, can be set to protect regions in the Flash memory
from accidental program or erase. Three separate memory regions, one growing upward from global
address 0x7F_8000 in the Flash memory (called the lower region), one growing downward from global
address 0x7F_FFFF in the Flash memory (called the higher region), and the remaining addresses in the
Flash memory, can be activated for protection. The Flash memory addresses covered by these protectable
regions are shown in the Flash memory map. The higher address region is mainly targeted to hold the boot
loader code since it covers the vector space. The lower address region can be used for EEPROM emulation
in an MCU without an EEPROM module since it can be left unprotected while the remaining addresses
are protected from program or erase. Default protection settings as well as security information that allows
the MCU to restrict access to the Flash module are stored in the Flash configuration field as described in
Table 3-1.
Table 3-1. Flash Configuration Field
Global Address
Size
(Bytes)
0x7F_FF00 – 0x7F_FF07
8
Backdoor Comparison Key
Refer to Section 3.6.1, “Unsecuring the MCU using Backdoor Key Access”
0x7F_FF08 – 0x7F_FF0C
5
Reserved
0x7F_FF0D
1
Flash Protection byte
Refer to Section 3.3.2.5, “Flash Protection Register (FPROT)”
0x7F_FF0E
1
Flash Nonvolatile byte
Refer to Section 3.3.2.8, “Flash Control Register (FCTL)”
0x7F_FF0F
1
Flash Security byte
Refer to Section 3.3.2.2, “Flash Security Register (FSEC)”
Description
MC9S12XHZ512 Data Sheet, Rev. 1.06
134
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
MODULE BASE + 0x0000
Flash Registers
16 bytes
MODULE BASE + 0x000F
FLASH START = 0x78_0000
Flash Protected/Unprotected Region
480 Kbytes
0x7F_8000
0x7F_8400
0x7F_8800
0x7F_9000
Flash Protected/Unprotected Lower Region
1, 2, 4, 8 Kbytes
0x7F_A000
Flash Protected/Unprotected Region
8 Kbytes (up to 29 Kbytes)
0x7F_C000
0x7F_E000
Flash Protected/Unprotected Higher Region
2, 4, 8, 16 Kbytes
0x7F_F000
0x7F_F800
FLASH END = 0x7F_FFFF
Flash Configuration Field
16 bytes (0x7F_FF00 - 0x7F_FF0F)
Figure 3-2. Flash Memory Map
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
135
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2
Register Descriptions
The Flash module contains a set of 16 control and status registers located between module base + 0x0000
and 0x000F. A summary of the Flash module registers is given in Figure 3-3. Detailed descriptions of each
register bit are provided.
Register
Name
0x0000
FCLKDIV
0x0001
FSEC
0x0002
FTSTMOD
0x0003
FCNFG
0x0004
FPROT
0x0005
FSTAT
0x0006
FCMD
0x0007
FCTL
0x0008
FADDRHI
0x0009
FADDRLO
0x000A
FDATAHI
0x000B
FDATALO
Bit 7
R
6
5
4
3
2
1
Bit 0
PRDIV8
FDIV5
FDIV4
FDIV3
FDIV2
FDIV1
FDIV0
RNV5
RNV4
RNV3
RNV2
0
0
0
0
0
0
0
0
0
0
FDIVLD
W
R
KEYEN
SEC
W
R
0
MRDS
W
R
CBEIE
CCIE
KEYACC
W
R
RNV6
FPOPEN
FPHDIS
FPHS
FPLDIS
FPLS
W
R
CCIF
CBEIF
0
PVIOL
BLANK
0
0
NV2
NV1
NV0
ACCERR
W
R
0
CMDB
W
R
0
NV6
NV5
NV4
NV3
W
R
FADDRHI
W
R
FADDRLO
W
R
FDATAHI
W
R
FDATALO
W
Figure 3-3. FTX512K4 Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
136
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Register
Name
0x000C
RESERVED1
0x000D
RESERVED2
0x000E
RESERVED3
0x000F
RESERVED4
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R
W
R
W
R
W
R
W
Figure 3-3. FTX512K4 Register Summary (continued)
3.3.2.1
Flash Clock Divider Register (FCLKDIV)
The FCLKDIV register is used to control timed events in program and erase algorithms.
Module Base + 0x0000
7
R
6
5
4
3
2
1
0
PRDIV8
FDIV5
FDIV4
FDIV3
FDIV2
FDIV1
FDIV0
0
0
0
0
0
0
0
FDIVLD
W
Reset
0
= Unimplemented or Reserved
Figure 3-4. Flash Clock Divider Register (FCLKDIV)
All bits in the FCLKDIV register are readable, bits 6-0 are write once and bit 7 is not writable.
Table 3-2. FCLKDIV Field Descriptions
Field
Description
7
FDIVLD
Clock Divider Loaded.
0 Register has not been written.
1 Register has been written to since the last reset.
6
PRDIV8
Enable Prescalar by 8.
0 The oscillator clock is directly fed into the clock divider.
1 The oscillator clock is divided by 8 before feeding into the clock divider.
5:0
FDIV[5:0]
Clock Divider Bits — The combination of PRDIV8 and FDIV[5:0] must divide the oscillator clock down to a
frequency of 150 kHz–200 kHz. The maximum divide ratio is 512. Please refer to Section 3.4.1.1, “Writing the
FCLKDIV Register” for more information.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
137
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.2
Flash Security Register (FSEC)
The FSEC register holds all bits associated with the security of the MCU and Flash module.
Module Base + 0x0001
7
R
6
KEYEN
5
4
3
2
RNV5
RNV4
RNV3
RNV2
F
F
F
F
1
0
SEC
W
Reset
F
F
F
F
= Unimplemented or Reserved
Figure 3-5. Flash Security Register (FSEC)
All bits in the FSEC register are readable but are not writable.
The FSEC register is loaded from the Flash Configuration Field at address 0x7F_FF0F during the reset
sequence, indicated by F in Figure 3-5.
Table 3-3. FSEC Field Descriptions
Field
Description
7:6
Backdoor Key Security Enable Bits — The KEYEN[1:0] bits define the enabling of backdoor key access to the
KEYEN[1:0] Flash module as shown in Table 3-4.
5:2
RNV[5:2]
Reserved Nonvolatile Bits — The RNV[5:2] bits should remain in the erased state for future enhancements.
1:0
SEC[1:0]
Flash Security Bits — The SEC[1:0] bits define the security state of the MCU as shown in Table 3-5. If the Flash
module is unsecured using backdoor key access, the SEC[1:0] bits are forced to 1:0.
Table 3-4. Flash KEYEN States
KEYEN[1:0]
Status of Backdoor Key Access
00
DISABLED
011
DISABLED
10
ENABLED
11
DISABLED
1 Preferred KEYEN state to disable Backdoor Key Access.
Table 3-5. Flash Security States
SEC[1:0]
Status of Security
00
SECURED
1
SECURED
01
10
UNSECURED
11
SECURED
1 Preferred SEC state to set MCU to secured state.
The security function in the Flash module is described in Section 3.6, “Flash Module Security”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
138
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.3
Flash Test Mode Register (FTSTMOD)
The FTSTMOD register is used to control Flash test features.
Module Base + 0x0002
7
R
6
5
0
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
MRDS
W
Reset
0
0
0
= Unimplemented or Reserved
Figure 3-6. Flash Test Mode Register (FTSTMOD —Normal Mode)
Module Base + 0x0002
7
R
6
5
4
0
MRDS
3
2
1
0
0
0
0
0
0
0
0
0
WRALL
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 3-7. Flash Test Mode Register (FTSTMOD — Special Mode)
MRDS bits are readable and writable while all remaining bits read 0 and are not writable in normal mode.
The WRALL bit is writable only in special mode to simplify mass erase and erase verify operations. When
writing to the FTSTMOD register in special mode, all unimplemented/reserved bits must be written to 0.
Table 3-6. FTSTMOD Field Descriptions
Field
Description
6:5
MRDS[1:0]
Margin Read Setting — The MRDS[1:0] bits are used to set the sense-amp margin level for reads of the Flash
array as shown in Table 3-7.
4
WRALL
Write to all Register Banks — If the WRALL bit is set, all banked FDATA registers sharing the same register
address will be written simultaneously during a register write.
0 Write only to the FDATA register bank selected using BKSEL.
1 Write to all FDATA register banks.
Table 3-7. FTSTMOD Margin Read Settings
MRDS[1:0]
Margin Read Setting
00
Normal
01
Program Margin1
10
Erase Margin2
11
Normal
1 Flash array reads will be sensitive to program margin.
2 Flash array reads will be sensitive to erase margin.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
139
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.4
Flash Configuration Register (FCNFG)
The FCNFG register enables the Flash interrupts and gates the security backdoor writes.
Module Base + 0x0003
7
6
5
CBEIE
CCIE
KEYACC
0
0
0
R
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
1
0
W
Reset
= Unimplemented or Reserved
Figure 3-8. Flash Configuration Register (FCNFG — Normal Mode)
Module Base + 0x0003
7
6
5
CBEIE
CCIE
KEYACC
0
0
0
R
4
3
2
0
0
0
BKSEL
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 3-9. Flash Configuration Register (FCNFG — Special Mode)
CBEIE, CCIE and KEYACC bits are readable and writable while all remaining bits read 0 and are not
writable in normal mode. KEYACC is only writable if KEYEN (see Section 3.3.2.2, “Flash Security
Register (FSEC)” is set to the enabled state. BKSEL is readable and writable in special mode to simplify
mass erase and erase verify operations. When writing to the FCNFG register in special mode, all
unimplemented/ reserved bits must be written to 0.
Table 3-8. FCNFG Field Descriptions
Field
Description
7
CBEIE
Command Buffer Empty Interrupt Enable — The CBEIE bit enables an interrupt in case of an empty command
buffer in the Flash module.
0 Command buffer empty interrupt disabled.
1 An interrupt will be requested whenever the CBEIF flag (see Section 3.3.2.6, “Flash Status Register (FSTAT)”)
is set.
6
CCIE
Command Complete Interrupt Enable — The CCIE bit enables an interrupt in case all commands have been
completed in the Flash module.
0 Command complete interrupt disabled.
1 An interrupt will be requested whenever the CCIF flag (see Section 3.3.2.6, “Flash Status Register (FSTAT)”)
is set.
5
KEYACC
Enable Security Key Writing
0 Flash writes are interpreted as the start of a command write sequence.
1 Writes to Flash array are interpreted as keys to open the backdoor. Reads of the Flash array return invalid
data.
1:0
Block Select — The BKSEL[1:0] bits indicates which register bank is active according to Table 3-9.
BKSEL[1:0]
MC9S12XHZ512 Data Sheet, Rev. 1.06
140
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Table 3-9. Flash Register Bank Selects
3.3.2.5
BKSEL[1:0]
Selected Block
00
Flash Block 0
01
Flash Block 1
10
Flash Block 2
11
Flash Block 3
Flash Protection Register (FPROT)
The FPROT register defines which Flash sectors are protected against program or erase operations.
Module Base + 0x0004
7
6
R
5
4
3
2
1
0
RNV6
FPOPEN
FPHDIS
FPHS
FPLDIS
FPLS
W
Reset
F
F
F
F
F
F
F
F
= Unimplemented or Reserved
Figure 3-10. Flash Protection Register (FPROT)
All bits in the FPROT register are readable and writable with restrictions (see Section 3.3.2.5.1, “Flash
Protection Restrictions”) except for RNV[6] which is only readable.
During the reset sequence, the FPROT register is loaded from the Flash Configuration Field at global
address 0x7F_FF0D. To change the Flash protection that will be loaded during the reset sequence, the
upper sector of the Flash memory must be unprotected, then the Flash Protect/Security byte located as
described in Table 3-1 must be reprogrammed.
Trying to alter data in any protected area in the Flash memory will result in a protection violation error and
the PVIOL flag will be set in the FSTAT register. The mass erase of a Flash block is not possible if any of
the Flash sectors contained in the Flash block are protected.
Table 3-10. FPROT Field Descriptions
Field
Description
7
FPOPEN
Flash Protection Open — The FPOPEN bit determines the protection function for program or erase as shown
in Table 3-11.
0 The FPHDIS and FPLDIS bits define unprotected address ranges as specified by the corresponding
FPHS[1:0] and FPLS[1:0] bits. For an MCU without an EEPROM module, the FPOPEN clear state allows the
main part of the Flash block to be protected while a small address range can remain unprotected for EEPROM
emulation.
1 The FPHDIS and FPLDIS bits enable protection for the address range specified by the corresponding
FPHS[1:0] and FPLS[1:0] bits.
6
RNV6
Reserved Nonvolatile Bit — The RNV[6] bit should remain in the erased state for future enhancements.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
141
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Table 3-10. FPROT Field Descriptions (continued)
Field
5
FPHDIS
Description
Flash Protection Higher Address Range Disable — The FPHDIS bit determines whether there is a
protected/unprotected area in a specific region of the Flash memory ending with global address 0x7F_FFFF.
0 Protection/Unprotection enabled.
1 Protection/Unprotection disabled.
4:3
FPHS[1:0]
Flash Protection Higher Address Size — The FPHS[1:0] bits determine the size of the protected/unprotected
area as shown inTable 3-12. The FPHS[1:0] bits can only be written to while the FPHDIS bit is set.
2
FPLDIS
Flash Protection Lower Address Range Disable — The FPLDIS bit determines whether there is a
protected/unprotected area in a specific region of the Flash memory beginning with global address 0x7F_8000.
0 Protection/Unprotection enabled.
1 Protection/Unprotection disabled.
1:0
FPLS[1:0]
Flash Protection Lower Address Size — The FPLS[1:0] bits determine the size of the protected/unprotected
area as shown in Table 3-13. The FPLS[1:0] bits can only be written to while the FPLDIS bit is set.
Table 3-11. Flash Protection Function
Function1
FPOPEN
FPHDIS
FPLDIS
1
1
1
No Protection
1
1
0
Protected Low Range
1
0
1
Protected High Range
1
0
0
Protected High and Low Ranges
0
1
1
Full Flash memory Protected
0
1
0
Unprotected Low Range
0
0
1
Unprotected High Range
0
0
0
Unprotected High and Low Ranges
1 For range sizes, refer to Table 3-12 and Table 3-13.
Table 3-12. Flash Protection Higher Address Range
FPHS[1:0]
Global
Address Range
Protected Size
00
0x7F_F800–0x7F_FFFF
2 Kbytes
01
0x7F_F000–0x7F_FFFF
4 Kbytes
10
0x7F_E000–0x7F_FFFF
8 Kbytes
11
0x7F_C000–0x7F_FFFF
16 Kbytes
Table 3-13. Flash Protection Lower Address Range
FPLS[1:0]
Global
Address Range
Protected Size
00
0x7F_8000–0x7F_83FF
1 Kbytes
01
0x7F_8000–0x7F_87FF
2 Kbytes
10
0x7F_8000–0x7F_8FFF
4 Kbytes
11
0x7F_8000–0x7F_9FFF
8 Kbytes
MC9S12XHZ512 Data Sheet, Rev. 1.06
142
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
All possible Flash protection scenarios are shown in Figure 3-11. Although the protection scheme is
loaded from the Flash array at global address 0x7F_FF0D during the reset sequence, it can be changed by
the user. This protection scheme can be used by applications requiring re-programming in single chip
mode while providing as much protection as possible if re-programming is not required.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
143
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
FPHDIS=1
FPLDIS=1
FPHDIS=1
FPLDIS=0
FPHDIS=0
FPLDIS=1
FPHDIS=0
FPLDIS=0
7
6
5
4
0x78_0000
Scenario
0x7F_8000
FPLS[1:0]
FPOPEN=1
FPHS[1:0]
0x7F_FFFF
3
2
Scenario
1
0
0x78_0000
0x7F_8000
FPLS[1:0]
FPOPEN=0
FPHS[1:0]
0x7F_FFFF
Unprotected region
Protected region with size
defined by FPLS
Protected region
not defined by FPLS, FPHS
Protected region with size
defined by FPHS
Figure 3-11. Flash Protection Scenarios
MC9S12XHZ512 Data Sheet, Rev. 1.06
144
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.5.1
Flash Protection Restrictions
The general guideline is that Flash protection can only be added and not removed. Table 3-14 specifies all
valid transitions between Flash protection scenarios. Any attempt to write an invalid scenario to the
FPROT register will be ignored and the FPROT register will remain unchanged. The contents of the
FPROT register reflect the active protection scenario. See the FPHS and FPLS descriptions for additional
restrictions.
Table 3-14. Flash Protection Scenario Transitions
To Protection Scenario1
From
Protection Scenario
0
1
2
3
0
X
X
X
X
1
X
2
4
X
4
X
X
X
X
X
X
X
X
X
X
7
X
X
7
X
3
6
6
X
X
5
5
X
X
X
X
X
X
1 Allowed transitions marked with X.
3.3.2.6
Flash Status Register (FSTAT)
The FSTAT register defines the operational status of the module.
Module Base + 0x0005
7
6
R
5
4
PVIOL
ACCERR
0
0
CCIF
CBEIF
3
2
1
0
0
BLANK
0
0
0
0
0
0
1
0
W
Reset
1
1
= Unimplemented or Reserved
Figure 3-12. Flash Status Register (FSTAT — Normal Mode)
Module Base + 0x0005
7
6
R
5
4
PVIOL
ACCERR
0
0
CCIF
CBEIF
3
2
0
BLANK
0
FAIL
W
Reset
1
1
0
0
0
0
= Unimplemented or Reserved
Figure 3-13. Flash Status Register (FSTAT — Special Mode)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
145
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
CBEIF, PVIOL, and ACCERR are readable and writable, CCIF and BLANK are readable and not writable,
remaining bits read 0 and are not writable in normal mode. FAIL is readable and writable in special mode.
FAIL must be clear in special mode when starting a command write sequence.
Table 3-15. FSTAT Field Descriptions
Field
Description
7
CBEIF
Command Buffer Empty Interrupt Flag — The CBEIF flag indicates that the address, data and command
buffers are empty so that a new command write sequence can be started. Writing a 0 to the CBEIF flag has no
effect on CBEIF. Writing a 0 to CBEIF after writing an aligned word to the Flash address space, but before CBEIF
is cleared, will abort a command write sequence and cause the ACCERR flag to be set. Writing a 0 to CBEIF
outside of a command write sequence will not set the ACCERR flag. The CBEIF flag is cleared by writing a 1 to
CBEIF. The CBEIF flag is used together with the CBEIE bit in the FCNFG register to generate an interrupt
request (see Figure 3-32).
0 Command buffers are full.
1 Command buffers are ready to accept a new command.
6
CCIF
Command Complete Interrupt Flag — The CCIF flag indicates that there are no more commands pending. The
CCIF flag is cleared when CBEIF is cleared and sets automatically upon completion of all active and pending
commands. The CCIF flag does not set when an active commands completes and a pending command is
fetched from the command buffer. Writing to the CCIF flag has no effect on CCIF. The CCIF flag is used together
with the CCIE bit in the FCNFG register to generate an interrupt request (see Figure 3-32).
0 Command in progress.
1 All commands are completed.
5
PVIOL
Protection Violation Flag —The PVIOL flag indicates an attempt was made to program or erase an address in
a protected area of the Flash memory during a command write sequence. Writing a 0 to the PVIOL flag has no
effect on PVIOL. The PVIOL flag is cleared by writing a 1 to PVIOL. While PVIOL is set, it is not possible to launch
a command or start a command write sequence.
0 No protection violation detected.
1 Protection violation has occurred.
4
ACCERR
Access Error Flag — The ACCERR flag indicates an illegal access has occurred to the Flash memory caused
by either a violation of the command write sequence (see Section 3.4.1.2, “Command Write Sequence”), issuing
an illegal Flash command (see Table 3-17), launching the sector erase abort command terminating a sector
erase operation early (see Section 3.4.2.6, “Sector Erase Abort Command”) or the execution of a CPU STOP
instruction while a command is executing (CCIF = 0). Writing a 0 to the ACCERR flag has no effect on ACCERR.
The ACCERR flag is cleared by writing a 1 to ACCERR.While ACCERR is set, it is not possible to launch a
command or start a command write sequence. If ACCERR is set by an erase verify operation or a data compress
operation, any buffered command will not launch.
0 No access error detected.
1 Access error has occurred.
2
BLANK
Flag Indicating the Erase Verify Operation Status — When the CCIF flag is set after completion of an erase
verify command, the BLANK flag indicates the result of the erase verify operation. The BLANK flag is cleared by
the Flash module when CBEIF is cleared as part of a new valid command write sequence. Writing to the BLANK
flag has no effect on BLANK.
0 Flash block verified as not erased.
1 Flash block verified as erased.
1
FAIL
Flag Indicating a Failed Flash Operation — The FAIL flag will set if the erase verify operation fails (selected
Flash block verified as not erased). Writing a 0 to the FAIL flag has no effect on FAIL. The FAIL flag is cleared by
writing a 1 to FAIL.
0 Flash operation completed without error.
1 Flash operation failed.
MC9S12XHZ512 Data Sheet, Rev. 1.06
146
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.3.2.7
Flash Command Register (FCMD)
The FCMD register is the Flash command register.
Module Base + 0x0006
7
R
6
5
4
3
2
1
0
0
0
0
0
CMDB
W
Reset
1
1
0
0
0
= Unimplemented or Reserved
Figure 3-14. Flash Command Register (FCMD)
All CMDB bits are readable and writable during a command write sequence while bit 7 reads 0 and is not
writable.
Table 3-16. FCMD Field Descriptions
Field
6:0
CMDB[6:0]
Description
Flash Command — Valid Flash commands are shown in Table 3-17. Writing any command other than those
listed in Table 3-17 sets the ACCERR flag in the FSTAT register.
Table 3-17. Valid Flash Command List
3.3.2.8
CMDB[6:0]
NVM Command
0x05
Erase Verify
0x06
Data Compress
0x20
Word Program
0x40
Sector Erase
0x41
Mass Erase
0x47
Sector Erase Abort
Flash Control Register (FCTL)
The FCTL register is the Flash control register.
Module Base + 0x0007
R
7
6
5
4
3
2
1
0
0
NV6
NV5
NV4
NV3
NV2
NV1
NV0
0
F
F
F
F
F
F
F
W
Reset
= Unimplemented or Reserved
Figure 3-15. Flash Control Register (FCTL)
All bits in the FCTL register are readable but are not writable.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
147
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
The FCTL NV bits are loaded from the Flash nonvolatile byte located at global address 0x7F_FF0E during
the reset sequence, indicated by F in Figure 3-15.
Table 3-18. FCTL Field Descriptions
Field
Description
6:0
NV[6:0]
Nonvolatile Bits — The NV[6:0] bits are available as nonvolatile bits. Refer to the Device User Guide for proper
use of the NV bits.
3.3.2.9
Flash Address Registers (FADDR)
The FADDRHI and FADDRLO registers are the Flash address registers.
Module Base + 0x0008
7
6
5
4
R
3
2
1
0
0
0
0
0
FADDRHI
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 3-16. Flash Address High Register (FADDRHI)
Module Base + 0x0009
7
6
5
4
R
3
2
1
0
0
0
0
0
FADDRLO
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 3-17. Flash Address Low Register (FADDRLO)
All FADDRHI and FADDRLO bits are readable but are not writable. After an array write as part of a
command write sequence, the FADDR registers will contain the mapped MCU address written.
3.3.2.10
Flash Data Registers (FDATA)
The FDATAHI and FDATALO registers are the Flash data registers.
Module Base + 0x000A
7
6
5
4
R
3
2
1
0
0
0
0
0
FDATAHI
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 3-18. Flash Data High Register (FDATAHI)
MC9S12XHZ512 Data Sheet, Rev. 1.06
148
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Module Base + 0x000B
7
6
5
4
R
3
2
1
0
0
0
0
0
FDATALO
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 3-19. Flash Data Low Register (FDATALO)
All FDATAHI and FDATALO bits are readable but are not writable. At the completion of a data compress
operation, the resulting 16-bit signature is stored in the FDATA registers. The data compression signature
is readable in the FDATA registers until a new command write sequence is started.
3.3.2.11
RESERVED1
This register is reserved for factory testing and is not accessible.
Module Base + 0x000C
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 3-20. RESERVED1
All bits read 0 and are not writable.
3.3.2.12
RESERVED2
This register is reserved for factory testing and is not accessible.
Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 3-21. RESERVED2
All bits read 0 and are not writable.
3.3.2.13
RESERVED3
This register is reserved for factory testing and is not accessible.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
149
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Module Base + 0x000E
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 3-22. RESERVED3
All bits read 0 and are not writable.
3.3.2.14
RESERVED4
This register is reserved for factory testing and is not accessible.
Module Base + 0x000F
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 3-23. RESERVED4
All bits read 0 and are not writable.
3.4
3.4.1
Functional Description
Flash Command Operations
Write operations are used to execute program, erase, erase verify, erase abort, and data compress
algorithms described in this section. The program and erase algorithms are controlled by a state machine
whose timebase, FCLK, is derived from the oscillator clock via a programmable divider. The command
register, as well as the associated address and data registers, operate as a buffer and a register (2-stage
FIFO) so that a second command along with the necessary data and address can be stored to the buffer
while the first command is still in progress. This pipelined operation allows a time optimization when
programming more than one word on a specific row in the Flash block as the high voltage generation can
be kept active in between two programming commands. The pipelined operation also allows a
simplification of command launching. Buffer empty as well as command completion are signalled by flags
in the Flash status register with corresponding interrupts generated, if enabled.
The next sections describe:
1. How to write the FCLKDIV register
2. Command write sequences to program, erase, erase verify, erase abort, and data compress
operations on the Flash memory
MC9S12XHZ512 Data Sheet, Rev. 1.06
150
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3. Valid Flash commands
4. Effects resulting from illegal Flash command write sequences or aborting Flash operations
3.4.1.1
Writing the FCLKDIV Register
Prior to issuing any Flash command after a reset, the user is required to write the FCLKDIV register to
divide the oscillator clock down to within the 150 kHz to 200 kHz range. Since the program and erase
timings are also a function of the bus clock, the FCLKDIV determination must take this information into
account.
If we define:
• FCLK as the clock of the Flash timing control block
• Tbus as the period of the bus clock
• INT(x) as taking the integer part of x (e.g. INT(4.323) = 4)
then FCLKDIV register bits PRDIV8 and FDIV[5:0] are to be set as described in Figure 3-24.
For example, if the oscillator clock frequency is 950kHz and the bus clock frequency is 10MHz,
FCLKDIV bits FDIV[5:0] should be set to 0x04 (000100) and bit PRDIV8 set to 0. The resulting FCLK
frequency is then 190kHz. As a result, the Flash program and erase algorithm timings are increased over
the optimum target by:
( 200 – 190 ) ⁄ 200 × 100 = 5%
If the oscillator clock frequency is 16MHz and the bus clock frequency is 40MHz, FCLKDIV bits
FDIV[5:0] should be set to 0x0A (001010) and bit PRDIV8 set to 1. The resulting FCLK frequency is then
182kHz. In this case, the Flash program and erase algorithm timings are increased over the optimum target
by:
( 200 – 182 ) ⁄ 200 × 100 = 9%
CAUTION
Program and erase command execution time will increase proportionally
with the period of FCLK. Because of the impact of clock synchronization
on the accuracy of the functional timings, programming or erasing the Flash
memory cannot be performed if the bus clock runs at less than 1 MHz.
Programming or erasing the Flash memory with FCLK < 150 kHz should
be avoided. Setting FCLKDIV to a value such that FCLK < 150 kHz can
destroy the Flash memory due to overstress. Setting FCLKDIV to a value
such that (1/FCLK+Tbus) < 5µs can result in incomplete programming or
erasure of the Flash memory cells.
If the FCLKDIV register is written, the FDIVLD bit is set automatically. If the FDIVLD bit is 0, the
FCLKDIV register has not been written since the last reset. If the FCLKDIV register has not been written
to, the Flash command loaded during a command write sequence will not execute and the ACCERR flag
in the FSTAT register will set.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
151
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Tbus < 1µs?
no
ALL COMMANDS IMPOSSIBLE
yes
PRDIV8=0 (reset)
oscillator_clock
12.8MHz?
no
yes
PRDIV8=1
PRDCLK=oscillator_clock/8
PRDCLK[MHz]*(5+Tbus[µs])
an integer?
yes
PRDCLK=oscillator_clock
no
FDIV[5:0]=INT(PRDCLK[MHz]*(5+Tbus[µs]))
FDIV[5:0]=PRDCLK[MHz]*(5+Tbus[µs])-1
TRY TO DECREASE Tbus
FCLK=(PRDCLK)/(1+FDIV[5:0])
1/FCLK[MHz] + Tbus[µs] > 5
AND
FCLK > 0.15MHz
?
yes
END
no
yes
FDIV[5:0] > 4?
no
ALL COMMANDS IMPOSSIBLE
Figure 3-24. Determination Procedure for PRDIV8 and FDIV Bits
MC9S12XHZ512 Data Sheet, Rev. 1.06
152
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.1.2
Command Write Sequence
The Flash command controller is used to supervise the command write sequence to execute program,
erase, erase verify, erase abort, and data compress algorithms.
Before starting a command write sequence, the ACCERR and PVIOL flags in the FSTAT register must be
clear (see Section 3.3.2.6, “Flash Status Register (FSTAT)”) and the CBEIF flag should be tested to
determine the state of the address, data and command buffers. If the CBEIF flag is set, indicating the
buffers are empty, a new command write sequence can be started. If the CBEIF flag is clear, indicating the
buffers are not available, a new command write sequence will overwrite the contents of the address, data
and command buffers.
A command write sequence consists of three steps which must be strictly adhered to with writes to the
Flash module not permitted between the steps. However, Flash register and array reads are allowed during
a command write sequence. The basic command write sequence is as follows:
1. Write to a valid address in the Flash memory. Addresses in multiple Flash blocks can be written to
as long as the location is at the same relative address in each available Flash block. Multiple
addresses must be written in Flash block order starting with the lower Flash block.
2. Write a valid command to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the command.
The address written in step 1 will be stored in the FADDR registers and the data will be stored in the
FDATA registers. If the CBEIF flag in the FSTAT register is clear when the first Flash array write occurs,
the contents of the address and data buffers will be overwritten and the CBEIF flag will be set. When the
CBEIF flag is cleared, the CCIF flag is cleared on the same bus cycle by the Flash command controller
indicating that the command was successfully launched. For all command write sequences except data
compress and sector erase abort, the CBEIF flag will set four bus cycles after the CCIF flag is cleared
indicating that the address, data, and command buffers are ready for a new command write sequence to
begin. For data compress and sector erase abort operations, the CBEIF flag will remain clear until the
operation completes. Except for the sector erase abort command, a buffered command will wait for the
active operation to be completed before being launched. The sector erase abort command is launched when
the CBEIF flag is cleared as part of a sector erase abort command write sequence. Once a command is
launched, the completion of the command operation is indicated by the setting of the CCIF flag in the
FSTAT register. The CCIF flag will set upon completion of all active and buffered commands.
3.4.2
Flash Commands
Table 3-19 summarizes the valid Flash commands along with the effects of the commands on the Flash
block.
Table 3-19. Flash Command Description
FCMDB
0x05
NVM
Command
Erase
Verify
Function on Flash Memory
Verify all memory bytes in the Flash block are erased.
If the Flash block is erased, the BLANK flag in the FSTAT register will set upon command
completion.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
153
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Table 3-19. Flash Command Description
NVM
Command
Function on Flash Memory
0x06
Data
Compress
Compress data from a selected portion of the Flash block.
The resulting signature is stored in the FDATA register.
0x20
Program
0x40
Sector
Erase
Erase all memory bytes in a sector of the Flash block.
0x41
Mass
Erase
Erase all memory bytes in the Flash block.
A mass erase of the full Flash block is only possible when FPLDIS, FPHDIS and
FPOPEN bits in the FPROT register are set prior to launching the command.
0x47
Sector
Erase
Abort
Abort the sector erase operation.
The sector erase operation will terminate according to a set procedure. The Flash sector
should not be considered erased if the ACCERR flag is set upon command completion.
FCMDB
Program a word (two bytes) in the Flash block.
CAUTION
A Flash word must be in the erased state before being programmed.
Cumulative programming of bits within a Flash word is not allowed.
MC9S12XHZ512 Data Sheet, Rev. 1.06
154
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.1
Erase Verify Command
The erase verify operation will verify that a Flash block is erased.
An example flow to execute the erase verify operation is shown in Figure 3-25. The erase verify command
write sequence is as follows:
1. Write an aligned word to a valid address in the Flash array memory to start the command write
sequence for the erase verify command. The address and data written will be ignored. Multiple
Flash blocks can be simultaneously erase verified by writing to the same relative address in each
Flash block.
2. Write the erase verify command, 0x05, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the erase verify
command.
After launching the erase verify command, the CCIF flag in the FSTAT register will set after the operation
has completed unless a new command write sequence has been buffered. The number of bus cycles
required to execute the erase verify operation is equal to the number of addresses in a Flash block plus 14
bus cycles as measured from the time the CBEIF flag is cleared until the CCIF flag is set. Upon completion
of the erase verify operation, the BLANK flag in the FSTAT register will be set if all addresses in the
selected Flash blocks are verified to be erased. If any address in a selected Flash block is not erased, the
erase verify operation will terminate and the BLANK flag in the FSTAT register will remain clear. The
MRDS bits in the FTSTMOD register will determine the sense-amp margin setting during the erase verify
operation.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
155
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Read: FCLKDIV register
Clock Register
Written
Check
FDIVLD
Set?
yes
NOTE: FCLKDIV needs to
be set once after each reset.
no
Write: FCLKDIV register
Read: FSTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
1.
Simultaneous
Multiple Flash Block
Decision
ACCERR/
PVIOL
Set?
no
yes
Write: FSTAT register
Clear ACCERR/PVIOL 0x30
Write: Flash Block Address
and Dummy Data
Next
Flash
Block?
yes
2.
no
Write: FCMD register
Erase Verify Command 0x05
3.
Write: FSTAT register
Clear CBEIF 0x80
Decrement Global Address
by 128K
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
Erase Verify
Status
BLANK
Set?
no
yes
EXIT Flash Block
Erased
EXIT
Flash Block
Not Erased
Figure 3-25. Example Erase Verify Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
156
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.2
Data Compress Command
The data compress operation will check Flash code integrity by compressing data from a selected portion
of the Flash memory into a signature analyzer.
An example flow to execute the data compress operation is shown in Figure 3-26. The data compress
command write sequence is as follows:
1. Write an aligned word to a valid address in the Flash array memory to start the command write
sequence for the data compress command. The address written determines the starting address for
the data compress operation and the data written determines the number of consecutive words to
compress with an upper limit of 16,384. Multiple Flash blocks can be simultaneously compressed
by writing to the same relative address in each Flash block. If more than one Flash block is written
to in this step, the first data written will determine the number of consecutive words to compress in
each selected Flash block.
2. Write the data compress command, 0x06, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the data compress
command.
After launching the data compress command, the CCIF flag in the FSTAT register will set after the data
compress operation has completed. The number of bus cycles required to execute the data compress
operation is equal to two times the number of consecutive words to compress plus the number of Flash
blocks simultaneously compressed plus 18 bus cycles as measured from the time the CBEIF flag is cleared
until the CCIF flag is set. Once the CCIF flag is set, the signature generated by the data compress operation
is available in the FDATA registers. The signature in the FDATA registers can be compared to the expected
signature to determine the integrity of the selected data stored in the selected Flash memory. If the last
address of a Flash block is reached during the data compress operation, data compression will continue
with the starting address of the same Flash block. The MRDS bits in the FTSTMOD register will determine
the sense-amp margin setting during the data compress operation.
NOTE
Since the FDATA registers (or data buffer) are written to as part of the data
compress operation, a command write sequence is not allowed to be
buffered behind a data compress command write sequence. The CBEIF flag
will not set after launching the data compress command to indicate that a
command should not be buffered behind it. If an attempt is made to start a
new command write sequence with a data compress operation active, the
ACCERR flag in the FSTAT register will be set. A new command write
sequence should only be started after reading the signature stored in the
FDATA registers.
In order to take corrective action, it is recommended that the data compress command be executed on a
Flash sector or subset of a Flash sector. If the data compress operation on a Flash sector returns an invalid
signature, the Flash sector should be erased using the sector erase command and then reprogrammed using
the program command.
The data compress command can be used to verify that a sector or sequential set of sectors are erased.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
157
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Read: FCLKDIV register
Clock Register
Written
Check
FDIVLD
Set?
yes
NOTE: FCLKDIV needs to
be set once after each reset.
no
Write: FCLKDIV register
Read: FSTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
ACCERR/
PVIOL
Set?
no
Access Error and
Protection Violation
Check
yes
Write: FSTAT register
Clear ACCERR/PVIOL 0x30
Write: Flash Address to start
compression and number of word
addresses to compress (max 16,384)
1.
NOTE: address used to select
Flash block; data ignored.
Simultaneous
Multiple Flash Block
Decision
Next
Flash
Block?
yes
2.
no
Write: FCMD register
Data Compress Command 0x06
3.
Write: FSTAT register
Clear CBEIF 0x80
Decrement Global Address
by 128K
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
Read: FDATA registers
Data Compress Signature
Signature
Valid?
no
Erase and Reprogram
Flash Sector(s) Compressed
yes
EXIT
Figure 3-26. Example Data Compress Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
158
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.2.1
Data Compress Operation
The Flash module contains a 16-bit multiple-input signature register (MISR) for each Flash block to
generate a 16-bit signature based on selected Flash array data. If multiple Flash blocks are selected for
simultaneous compression, then the signature from each Flash block is further compressed to generate a
single 16-bit signature. The final 16-bit signature, found in the FDATA registers after the data compress
operation has completed, is based on the following logic equation which is executed on every data
compression cycle during the operation:
MISR[15:0] = {MISR[14:0], ^MISR[15,4,2,1]} ^ DATA[15:0]
Eqn. 3-1
where MISR is the content of the internal signature register associated with each Flash block and DATA
is the data to be compressed as shown in Figure 3-27.
DATA[0]
+
DATA[1]
DQ
DATA[2]
+
M0
>
+
DQ
M1
>
DATA[3]
+
DQ
M2
>
+
DATA[4]
DQ
M3
>
+
+
DATA[5]
+
DQ
M4
>
DATA[15]
DQ
M5
>
...
+
DQ
M15
>
+
+ = Exclusive-OR
MISR[15:0] = Q[15:0]
Figure 3-27. 16-Bit MISR Diagram
During the data compress operation, the following steps are executed:
1. MISR for each Flash block is reset to 0xFFFF.
2. Initialized DATA equal to 0xFFFF is compressed into the MISR for each selected Flash block
which results in the MISR containing 0x0001.
3. DATA equal to the selected Flash array data range is read and compressed into the MISR for each
selected Flash block with addresses incrementing.
4. DATA equal to the selected Flash array data range is read and compressed into the MISR for each
selected Flash block with addresses decrementing.
5. If Flash block 0 is selected for compression, DATA equal to the contents of the MISR for Flash
block 0 is compressed into the MISR for Flash block 0. If data in Flash block 0 was not selected
for compression, the MISR for Flash block 0 contains 0xFFFF.
6. If Flash block 1 is selected for compression, DATA equal to the contents of the MISR for Flash
block 1 is compressed into the MISR for Flash block 0.
7. If Flash block 2 is selected for compression, DATA equal to the contents of the MISR for Flash
block 2 is compressed into the MISR for Flash block 0.
8. If Flash block 3 is selected for compression, DATA equal to the contents of the MISR for Flash
block 3 is compressed into the MISR for Flash block 0.
9. If Flash block 4 is selected for compression, DATA equal to the contents of the MISR for Flash
block 4 is compressed into the MISR for Flash block 0.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
159
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
10. If Flash block 5 is selected for compression, DATA equal to the contents of the MISR for Flash
block 5 is compressed into the MISR for Flash block 0.
11. If Flash block 6 is selected for compression, DATA equal to the contents of the MISR for Flash
block 6 is compressed into the MISR for Flash block 0.
12. If Flash block 7 is selected for compression, DATA equal to the contents of the MISR for Flash
block 7 is compressed into the MISR for Flash block 0.
13. The contents of the MISR for Flash block 0 are written to the FDATA registers.
MC9S12XHZ512 Data Sheet, Rev. 1.06
160
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.3
Program Command
The program operation will program a previously erased word in the Flash memory using an embedded
algorithm.
An example flow to execute the program operation is shown in Figure 3-28. The program command write
sequence is as follows:
1. Write an aligned word to a valid address in the Flash array memory to start the command write
sequence for the program command. The data written will be programmed to the address written.
Multiple Flash blocks can be simultaneously programmed by writing to the same relative address
in each Flash block.
2. Write the program command, 0x20, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the program
command.
If a word to be programmed is in a protected area of the Flash block, the PVIOL flag in the FSTAT register
will set and the program command will not launch. Once the program command has successfully launched,
the CCIF flag in the FSTAT register will set after the program operation has completed unless a new
command write sequence has been buffered. By executing a new program command write sequence on
sequential words after the CBEIF flag in the FSTAT register has been set, up to 55% faster programming
time per word can be effectively achieved than by waiting for the CCIF flag to set after each program
operation.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
161
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Read: FCLKDIV register
Clock Register
Written
Check
FDIVLD
Set?
yes
NOTE: FCLKDIV needs to
be set once after each reset.
no
Write: FCLKDIV register
Read: FSTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
1.
Simultaneous
Multiple Flash Block
Decision
ACCERR/
PVIOL
Set?
no
yes
Write: FSTAT register
Clear ACCERR/PVIOL 0x30
Write: Flash Address
and program Data
Next
Flash
Block?
2.
no
Write: FCMD register
Program Command 0x20
3.
Write: FSTAT register
Clear CBEIF 0x80
yes
Decrement Global Address
by 128K
Read: FSTAT register
Bit Polling for
Buffer Empty
Check
no
CBEIF
Set?
yes
Sequential
Programming
Decision
Next
Word?
yes
no
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 3-28. Example Program Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
162
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.4
Sector Erase Command
The sector erase operation will erase all addresses in a 1 Kbyte sector of Flash memory using an embedded
algorithm.
An example flow to execute the sector erase operation is shown in Figure 3-29. The sector erase command
write sequence is as follows:
1. Write an aligned word to a valid address in the Flash array memory to start the command write
sequence for the sector erase command. The Flash address written determines the sector to be
erased while global address bits [9:0] and the data written are ignored. Multiple Flash sectors can
be simultaneously erased by writing to the same relative address in each Flash block.
2. Write the sector erase command, 0x40, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the sector erase
command.
If a Flash sector to be erased is in a protected area of the Flash block, the PVIOL flag in the FSTAT register
will set and the sector erase command will not launch. Once the sector erase command has successfully
launched, the CCIF flag in the FSTAT register will set after the sector erase operation has completed unless
a new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
163
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Read: FCLKDIV register
Clock Register
Written
Check
FDIVLD
Set?
yes
NOTE: FCLKDIV needs to
be set once after each reset.
no
Write: FCLKDIV register
Read: FSTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
1.
Simultaneous
Multiple Flash Block
Decision
ACCERR/
PVIOL
Set?
no
yes
Write: FSTAT register
Clear ACCERR/PVIOL 0x30
Write: Flash Sector Address
and Dummy Data
Next
Flash
Block?
yes
2.
no
Write: FCMD register
Sector Erase Command 0x40
3.
Write: FSTAT register
Clear CBEIF 0x80
Decrement Global Address
by 128K
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 3-29. Example Sector Erase Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
164
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.5
Mass Erase Command
The mass erase operation will erase all addresses in a Flash block using an embedded algorithm.
An example flow to execute the mass erase operation is shown in Figure 3-30. The mass erase command
write sequence is as follows:
1. Write an aligned word to any valid address in a Flash block to start the command write sequence
for the mass erase command. The data written will be ignored while the address written determines
which Flash block is erased. Multiple Flash blocks can be simultaneously mass erased by writing
to the same relative address in each Flash block.
2. Write the mass erase command, 0x41, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the mass erase
command.
If a Flash block to be erased contains any protected area, the PVIOL flag in the FSTAT register will set and
the mass erase command will not launch. Once the mass erase command has successfully launched, the
CCIF flag in the FSTAT register will set after the mass erase operation has completed unless a new
command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
165
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
START
Read: FCLKDIV register
Clock Register
Written
Check
FDIVLD
Set?
yes
NOTE: FCLKDIV needs to
be set once after each reset.
no
Write: FCLKDIV register
Read: FSTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
1.
Simultaneous
Multiple Flash Block
Decision
ACCERR/
PVIOL
Set?
no
yes
Write: FSTAT register
Clear ACCERR/PVIOL 0x30
Write: Flash Block Address
and Dummy Data
Next
Flash
Block?
yes
2.
no
Write: FCMD register
Mass Erase Command 0x41
3.
Write: FSTAT register
Clear CBEIF 0x80
Decrement Global Address
by 128K
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 3-30. Example Mass Erase Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
166
Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.2.6
Sector Erase Abort Command
The sector erase abort operation will terminate the active sector erase operation so that other sectors in a
Flash block are available for read and program operations without waiting for the sector erase operation to
complete.
An example flow to execute the sector erase abort operation is shown in Figure 3-31. The sector erase abort
command write sequence is as follows:
1. Write an aligned word to any valid address in the Flash array memory to start the command write
sequence for the sector erase abort command. The address and data written are ignored.
2. Write the sector erase abort command, 0x47, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the sector erase abort
command.
If the sector erase abort command is launched resulting in the early termination of an active sector erase
operation, the ACCERR flag will set once the operation completes as indicated by the CCIF flag being set.
The ACCERR flag sets to inform the user that the Flash sector may not be fully erased and a new sector
erase command must be launched before programming any location in that specific sector. If the sector
erase abort command is launched but the active sector erase operation completes normally, the ACCERR
flag will not set upon completion of the operation as indicated by the CCIF flag being set. Therefore, if the
ACCERR flag is not set after the sector erase abort command has completed, a Flash sector being erased
when the abort command was launched will be fully erased. The maximum number of cycles required to
abort a sector erase operation is equal to four FCLK periods (see Section 3.4.1.1, “Writing the FCLKDIV
Register”) plus five bus cycles as measured from the time the CBEIF flag is cleared until the CCIF flag is
set. If sectors in multiple Flash blocks are being simultaneously erased, the sector erase abort operation
will be applied to all active Flash blocks without writing to each Flash block in the sector erase abort
command write sequence.
NOTE
Since the ACCERR bit in the FSTAT register may be set at the completion
of the sector erase abort operation, a command write sequence is not
allowed to be buffered behind a sector erase abort command write sequence.
The CBEIF flag will not set after launching the sector erase abort command
to indicate that a command should not be buffered behind it. If an attempt is
made to start a new command write sequence with a sector erase abort
operation active, the ACCERR flag in the FSTAT register will be set. A new
command write sequence may be started after clearing the ACCERR flag, if
set.
NOTE
The sector erase abort command should be used sparingly since a sector
erase operation that is aborted counts as a complete program/erase cycle.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
167
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Execute Sector Erase Command Flow
Read: FSTAT register
Bit Polling for
Command
Completion Check
CCIF
Set?
Erase
Abort
Needed?
no
yes
Sector Erase
Completed
no
yes
EXIT
1.
Write: Dummy Flash Address
and Dummy Data
2.
Write: FCMD register
Sector Erase Abort Cmd 0x47
3.
Write: FSTAT register
Clear CBEIF 0x80
Read: FSTAT register
Bit Polling for
Command
Completion Check
CCIF
Set?
no
yes
Access
Error Check
ACCERR
Set?
yes
Write: FSTAT register
Clear ACCERR 0x10
no
Sector Erase
Completed
EXIT
Sector Erase
Aborted
EXIT
Figure 3-31. Example Sector Erase Abort Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.4.3
Illegal Flash Operations
The ACCERR flag will be set during the command write sequence if any of the following illegal steps are
performed, causing the command write sequence to immediately abort:
1. Writing to a Flash address before initializing the FCLKDIV register.
2. Writing a byte or misaligned word to a valid Flash address.
3. Starting a command write sequence while a data compress operation is active.
4. Starting a command write sequence while a sector erase abort operation is active.
5. Writing a Flash address in step 1 of a command write sequence that is not the same relative address
as the first one written in the same command write sequence.
6. Writing to any Flash register other than FCMD after writing to a Flash address.
7. Writing a second command to the FCMD register in the same command write sequence.
8. Writing an invalid command to the FCMD register.
9. When security is enabled, writing a command other than mass erase to the FCMD register when
the write originates from a non-secure memory location or from the Background Debug Mode.
10. Writing to a Flash address after writing to the FCMD register.
11. Writing to any Flash register other than FSTAT (to clear CBEIF) after writing to the FCMD
register.
12. Writing a 0 to the CBEIF flag in the FSTAT register to abort a command write sequence.
The ACCERR flag will not be set if any Flash register is read during a valid command write sequence.
The ACCERR flag will also be set if any of the following events occur:
1. Launching the sector erase abort command while a sector erase operation is active which results in
the early termination of the sector erase operation (see Section 3.4.2.6, “Sector Erase Abort
Command”).
2. The MCU enters stop mode and a program or erase operation is in progress. The operation is
aborted immediately and any pending command is purged (see Section 3.5.2, “Stop Mode”).
If the Flash memory is read during execution of an algorithm (CCIF = 0), the read operation will return
invalid data and the ACCERR flag will not be set.
If the ACCERR flag is set in the FSTAT register, the user must clear the ACCERR flag before starting
another command write sequence (see Section 3.3.2.6, “Flash Status Register (FSTAT)”).
The PVIOL flag will be set after the command is written to the FCMD register during a command write
sequence if any of the following illegal operations are attempted, causing the command write sequence to
immediately abort:
1. Writing the program command if an address written in the command write sequence was in a
protected area of the Flash memory
2. Writing the sector erase command if an address written in the command write sequence was in a
protected area of the Flash memory
3. Writing the mass erase command to a Flash block while any Flash protection is enabled in the
block
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
169
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
If the PVIOL flag is set in the FSTAT register, the user must clear the PVIOL flag before starting another
command write sequence (see Section 3.3.2.6, “Flash Status Register (FSTAT)”).
3.5
3.5.1
Operating Modes
Wait Mode
If a command is active (CCIF = 0) when the MCU enters wait mode, the active command and any buffered
command will be completed.
The Flash module can recover the MCU from wait mode if the CBEIF and CCIF interrupts are enabled
(see Section 3.8, “Interrupts”).
3.5.2
Stop Mode
If a command is active (CCIF = 0) when the MCU enters stop mode, the operation will be aborted and, if
the operation is program or erase, the Flash array data being programmed or erased may be corrupted and
the CCIF and ACCERR flags will be set. If active, the high voltage circuitry to the Flash memory will
immediately be switched off when entering stop mode. Upon exit from stop mode, the CBEIF flag is set
and any buffered command will not be launched. The ACCERR flag must be cleared before starting a
command write sequence (see Section 3.4.1.2, “Command Write Sequence”).
NOTE
As active commands are immediately aborted when the MCU enters stop
mode, it is strongly recommended that the user does not use the STOP
instruction during program or erase operations.
3.5.3
Background Debug Mode
In background debug mode (BDM), the FPROT register is writable. If the MCU is unsecured, then all
Flash commands listed in Table 3-19 can be executed. If the MCU is secured and is in special single chip
mode, only mass erase can be executed.
3.6
Flash Module Security
The Flash module provides the necessary security information to the MCU. After each reset, the Flash
module determines the security state of the MCU as defined in Section 3.3.2.2, “Flash Security Register
(FSEC)”.
The contents of the Flash security byte at 0x7F_FF0F in the Flash Configuration Field must be changed
directly by programming 0x7F_FF0F when the MCU is unsecured and the higher address sector is
unprotected. If the Flash security byte is left in a secured state, any reset will cause the MCU to initialize
to a secure operating mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
3.6.1
Unsecuring the MCU using Backdoor Key Access
The MCU may be unsecured by using the backdoor key access feature which requires knowledge of the
contents of the backdoor keys (four 16-bit words programmed at addresses 0x7F_FF00–0x7F_FF07). If
the KEYEN[1:0] bits are in the enabled state (see Section 3.3.2.2, “Flash Security Register (FSEC)”) and
the KEYACC bit is set, a write to a backdoor key address in the Flash memory triggers a comparison
between the written data and the backdoor key data stored in the Flash memory. If all four words of data
are written to the correct addresses in the correct order and the data matches the backdoor keys stored in
the Flash memory, the MCU will be unsecured. The data must be written to the backdoor keys sequentially
starting with 0x7F_FF00–1 and ending with 0x7F_FF06–7. 0x0000 and 0xFFFF are not permitted as
backdoor keys. While the KEYACC bit is set, reads of the Flash memory will return invalid data.
The user code stored in the Flash memory must have a method of receiving the backdoor keys from an
external stimulus. This external stimulus would typically be through one of the on-chip serial ports.
If the KEYEN[1:0] bits are in the enabled state (see Section 3.3.2.2, “Flash Security Register (FSEC)”),
the MCU can be unsecured by the backdoor key access sequence described below:
1. Set the KEYACC bit in the Flash Configuration Register (FCNFG).
2. Write the correct four 16-bit words to Flash addresses 0xFF00–0xFF07 sequentially starting with
0x7F_FF00.
3. Clear the KEYACC bit. Depending on the user code used to write the backdoor keys, a wait cycle
(NOP) may be required before clearing the KEYACC bit.
4. If all four 16-bit words match the backdoor keys stored in Flash addresses
0x7F_FF00–0x7F_FF07, the MCU is unsecured and the SEC[1:0] bits in the FSEC register are
forced to the unsecure state of 1:0.
The backdoor key access sequence is monitored by an internal security state machine. An illegal operation
during the backdoor key access sequence will cause the security state machine to lock, leaving the MCU
in the secured state. A reset of the MCU will cause the security state machine to exit the lock state and
allow a new backdoor key access sequence to be attempted. The following operations during the backdoor
key access sequence will lock the security state machine:
1. If any of the four 16-bit words does not match the backdoor keys programmed in the Flash array.
2. If the four 16-bit words are written in the wrong sequence.
3. If more than four 16-bit words are written.
4. If any of the four 16-bit words written are 0x0000 or 0xFFFF.
5. If the KEYACC bit does not remain set while the four 16-bit words are written.
6. If any two of the four 16-bit words are written on successive MCU clock cycles.
After the backdoor keys have been correctly matched, the MCU will be unsecured. Once the MCU is
unsecured, the Flash security byte can be programmed to the unsecure state, if desired.
In the unsecure state, the user has full control of the contents of the backdoor keys by programming
addresses 0x7F_FF00–0x7F_FF07 in the Flash Configuration Field.
The security as defined in the Flash security byte (0x7F_FF0F) is not changed by using the backdoor key
access sequence to unsecure. The backdoor keys stored in addresses 0x7F_FF00–0x7F_FF07 are
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
171
Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
unaffected by the backdoor key access sequence. After the next reset of the MCU, the security state of the
Flash module is determined by the Flash security byte (0x7F_FF0F). The backdoor key access sequence
has no effect on the program and erase protections defined in the Flash protection register.
It is not possible to unsecure the MCU in special single chip mode by using the backdoor key access
sequence in background debug mode (BDM).
3.6.2
Unsecuring the MCU in Special Single Chip Mode using BDM
The MCU can be unsecured in special single chip mode by erasing the Flash module by the following
method:
• Reset the MCU into special single chip mode, delay while the erase test is performed by the BDM
secure ROM, send BDM commands to disable protection in the Flash module, and execute a mass
erase command write sequence to erase the Flash memory.
After the CCIF flag sets to indicate that the mass operation has completed, reset the MCU into special
single chip mode. The BDM secure ROM will verify that the Flash memory is erased and will assert the
UNSEC bit in the BDM status register. This BDM action will cause the MCU to override the Flash security
state and the MCU will be unsecured. All BDM commands will be enabled and the Flash security byte
may be programmed to the unsecure state by the following method:
• Send BDM commands to execute a word program sequence to program the Flash security byte to
the unsecured state and reset the MCU.
3.7
3.7.1
Resets
Flash Reset Sequence
On each reset, the Flash module executes a reset sequence to hold CPU activity while loading the following
registers from the Flash memory according to Table 3-1:
• FPROT — Flash Protection Register (see Section 3.3.2.5).
• FCTL - Flash Control Register (see Section 3.3.2.8).
• FSEC — Flash Security Register (see Section 3.3.2.2).
3.7.2
Reset While Flash Command Active
If a reset occurs while any Flash command is in progress, that command will be immediately aborted. The
state of the word being programmed or the sector/block being erased is not guaranteed.
3.8
Interrupts
The Flash module can generate an interrupt when all Flash command operations have completed, when the
Flash address, data and command buffers are empty.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
Table 3-20. Flash Interrupt Sources
Interrupt Source
Interrupt Flag
Local Enable
Global (CCR) Mask
Flash Address, Data and Command Buffers empty
CBEIF
(FSTAT register)
CBEIE
(FCNFG register)
I Bit
All Flash commands completed
CCIF
(FSTAT register)
CCIE
(FCNFG register)
I Bit
NOTE
Vector addresses and their relative interrupt priority are determined at the
MCU level.
3.8.1
Description of Flash Interrupt Operation
The logic used for generating interrupts is shown in Figure 3-32.
The Flash module uses the CBEIF and CCIF flags in combination with the CBIE and CCIE enable bits to
generate the Flash command interrupt request.
CBEIF
CBEIE
Flash Command Interrupt Request
CCIF
CCIE
Figure 3-32. Flash Interrupt Implementation
For a detailed description of the register bits, refer to Section 3.3.2.4, “Flash Configuration Register
(FCNFG)” and Section 3.3.2.6, “Flash Status Register (FSTAT)”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
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Chapter 3 512 Kbyte Flash Module (S12XFTX512K4V3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
174
Freescale Semiconductor
Chapter 4
4 Kbyte EEPROM Module (S12XEETX4KV2)
4.1
Introduction
This document describes the EETX4K module which includes a 4 Kbyte EEPROM (nonvolatile) memory.
The EEPROM memory may be read as either bytes, aligned words, or misaligned words. Read access time
is one bus cycle for bytes and aligned words, and two bus cycles for misaligned words.
The EEPROM memory is ideal for data storage for single-supply applications allowing for field
reprogramming without requiring external voltage sources for program or erase. Program and erase
functions are controlled by a command driven interface. The EEPROM module supports both block erase
(all memory bytes) and sector erase (4 memory bytes). An erased bit reads 1 and a programmed bit reads
0. The high voltage required to program and erase the EEPROM memory is generated internally. It is not
possible to read from the EEPROM block while it is being erased or programmed.
CAUTION
An EEPROM word (2 bytes) must be in the erased state before being
programmed. Cumulative programming of bits within a word is not allowed.
4.1.1
Glossary
Command Write Sequence — A three-step MCU instruction sequence to execute built-in algorithms
(including program and erase) on the EEPROM memory.
4.1.2
•
•
•
•
•
•
•
•
4.1.3
Features
4 Kbytes of EEPROM memory divided into 1024 sectors of 4 bytes
Automated program and erase algorithm
Interrupts on EEPROM command completion and command buffer empty
Fast sector erase and word program operation
2-stage command pipeline
Sector erase abort feature for critical interrupt response
Flexible protection scheme to prevent accidental program or erase
Single power supply for all EEPROM operations including program and erase
Modes of Operation
Program, erase and erase verify operations (please refer to Section 4.4.1, “EEPROM Command
Operations” for details).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
175
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.1.4
Block Diagram
A block diagram of the EEPROM module is shown in Figure 4-1.
EETX4K
Command
Interrupt
Request
EEPROM
Interface
Command Pipeline
EEPROM
cmd2
addr2
data2
cmd1
addr1
data1
Registers
2K * 16 Bits
sector 0
sector 1
Protection
sector 1023
Oscillator
Clock
Clock
Divider EECLK
Figure 4-1. EETX4K Block Diagram
4.2
External Signal Description
The EEPROM module contains no signals that connect off-chip.
4.3
Memory Map and Register Definition
This section describes the memory map and registers for the EEPROM module.
4.3.1
Module Memory Map
The EEPROM memory map is shown in Figure 4-2. The HCS12X architecture places the EEPROM
memory addresses between global addresses 0x13_F000 and 0x13_FFFF. The EPROT register, described
in Section 4.3.2.5, “EEPROM Protection Register (EPROT)”, can be set to protect the upper region in the
EEPROM memory from accidental program or erase. The EEPROM addresses covered by this protectable
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
region are shown in the EEPROM memory map. The default protection setting is stored in the EEPROM
configuration field as described in Table 4-1.
Table 4-1. EEPROM Configuration Field
Global Address
Size
(bytes)
0x13_FFFC
1
Reserved
0x13_FFFD
1
EEPROM Protection byte
Refer to Section 4.3.2.5, “EEPROM Protection Register (EPROT)”
0x13_FFFE – 0x13_FFFF
2
Reserved
Description
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
177
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
MODULE BASE+ 0x0000
EEPROM Registers
12 bytes
MODULE BASE + 0x000B
EEPROM START = 0x13_F000
EEPROM Memory
3584 bytes (up to 4032 bytes)
0x13_FE00
0x13_FE40
0x13_FE80
0x13_FEC0
0x13_FF00
EEPROM Memory Protected Region
64, 128, 192, 256, 320, 384, 448, 512 bytes
0x13_FF40
0x13_FF80
0x13_FFC0
EEPROM END = 0x13_FFFF
EEPROM Configuration Field
4 bytes (0x13_FFFC – 0x13_FFFF)
Figure 4-2. EEPROM Memory Map
MC9S12XHZ512 Data Sheet, Rev. 1.06
178
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.3.2
Register Descriptions
The EEPROM module also contains a set of 12 control and status registers located between EEPROM
module base + 0x0000 and 0x000B. A summary of the EEPROM module registers is given in Figure 4-3.
Detailed descriptions of each register bit are provided.
Register
Name
0x0000
ECLKDIV
Bit 7
R
W
0x0002
RESERVED2
W
0x0004
EPROT
R
W
R
W
0x0006
ECMD
W
R
2
1
Bit 0
PRDIV8
EDIV5
EDIV4
EDIV3
EDIV2
EDIV1
EDIV0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
CBEIE
CCIE
0
0
0
0
0
0
RNV5
RNV4
EPDIS
EPS2
EPS1
EPS0
PVIOL
ACCERR
0
BLANK
0
0
0
0
0
EDIVLD
EPOPEN
CBEIF
R
R
RNV6
CCIF
0
CMDB
0
0
0
0
0
0
0
0
0
0
W
0x0008
EADDRHI
W
0x0009
EADDRLO
W
0x000B
EDATALO
3
R
W
0x000A
EDATAHI
4
R
0x0005
ESTAT
0x0007
RESERVED3
5
W
0x0001
RESERVED1
0x0003
ECNFG
6
R
R
EABHI
EABLO
R
EDHI
W
R
EDLO
W
= Unimplemented or Reserved
Figure 4-3. EETX4K Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
179
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.3.2.1
EEPROM Clock Divider Register (ECLKDIV)
The ECLKDIV register is used to control timed events in program and erase algorithms.
Module Base + 0x0000
7
R
6
5
4
3
2
1
0
PRDIV8
EDIV5
EDIV4
EDIV3
EDIV2
EDIV1
EDIV0
0
0
0
0
0
0
0
EDIVLD
W
Reset
0
= Unimplemented or Reserved
Figure 4-4. EEPROM Clock Divider Register (ECLKDIV)
All bits in the ECLKDIV register are readable, bits 6–0 are write once and bit 7 is not writable.
Table 4-2. ECLKDIV Field Descriptions
Field
Description
7
EDIVLD
Clock Divider Loaded
0 Register has not been written.
1 Register has been written to since the last reset.
6
PRDIV8
Enable Prescalar by 8
0 The oscillator clock is directly fed into the ECLKDIV divider.
1 Enables a Prescalar by 8, to divide the oscillator clock before feeding into the clock divider.
5:0
EDIV[5:0]
4.3.2.2
Clock Divider Bits — The combination of PRDIV8 and EDIV[5:0] effectively divides the EEPROM module input
oscillator clock down to a frequency of 150 kHz – 200 kHz. The maximum divide ratio is 512. Please refer to
Section 4.4.1.1, “Writing the ECLKDIV Register” for more information.
RESERVED1
This register is reserved for factory testing and is not accessible.
Module Base + 0x0001
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 4-5. RESERVED1
All bits read 0 and are not writable.
4.3.2.3
RESERVED2
This register is reserved for factory testing and is not accessible.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Module Base + 0x0002
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 4-6. RESERVED2
All bits read 0 and are not writable.
4.3.2.4
EEPROM Configuration Register (ECNFG)
The ECNFG register enables the EEPROM interrupts.
Module Base + 0x0003
7
6
CBEIE
CCIE
0
0
R
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 4-7. EEPROM Configuration Register (ECNFG)
CBEIE and CCIE bits are readable and writable while all remaining bits read 0 and are not writable.
Table 4-3. ECNFG Field Descriptions
Field
Description
7
CBEIE
Command Buffer Empty Interrupt Enable — The CBEIE bit enables an interrupt in case of an empty command
buffer in the EEPROM module.
0 Command Buffer Empty interrupt disabled.
1 An interrupt will be requested whenever the CBEIF flag (see Section 4.3.2.6, “EEPROM Status Register
(ESTAT)”) is set.
6
CCIE
Command Complete Interrupt Enable — The CCIE bit enables an interrupt in case all commands have been
completed in the EEPROM module.
0 Command Complete interrupt disabled.
1 An interrupt will be requested whenever the CCIF flag (see Section 4.3.2.6, “EEPROM Status Register
(ESTAT)”) is set.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
181
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.3.2.5
EEPROM Protection Register (EPROT)
The EPROT register defines which EEPROM sectors are protected against program or erase operations.
Module Base + 0x0004
7
R
6
5
4
RNV6
RNV5
RNV4
EPOPEN
3
2
1
0
EPDIS
EPS2
EPS1
EPS0
F
F
F
F
W
Reset
F
F
F
F
= Unimplemented or Reserved
Figure 4-8. EEPROM Protection Register (EPROT)
During the reset sequence, the EPROT register is loaded from the EEPROM Protection byte at address
offset 0x0FFD (see Table 4-1).All bits in the EPROT register are readable and writable except for
RNV[6:4] which are only readable. The EPOPEN and EPDIS bits can only be written to the protected
state. The EPS bits can be written anytime until bit EPDIS is cleared. If the EPOPEN bit is cleared, the
state of the EPDIS and EPS bits is irrelevant.
To change the EEPROM protection that will be loaded during the reset sequence, the EEPROM memory
must be unprotected, then the EEPROM Protection byte must be reprogrammed. Trying to alter data in any
protected area in the EEPROM memory will result in a protection violation error and the PVIOL flag will
be set in the ESTAT register. The mass erase of an EEPROM block is possible only when protection is
fully disabled by setting the EPOPEN and EPDIS bits.
Table 4-4. EPROT Field Descriptions
Field
Description
7
EPOPEN
Opens the EEPROM for Program or Erase
0 The entire EEPROM memory is protected from program and erase.
1 The EEPROM sectors not protected are enabled for program or erase.
6:4
RNV[6:4]
Reserved Nonvolatile Bits — The RNV[6:4] bits should remain in the erased state “1” for future enhancements.
3
EPDIS
EEPROM Protection Address Range Disable — The EPDIS bit determines whether there is a protected area
in a specific region of the EEPROM memory ending with address offset 0x0FFF.
0 Protection enabled.
1 Protection disabled.
2:0
EPS[2:0]
EEPROM Protection Address Size — The EPS[2:0] bits determine the size of the protected area as shown
inTable 4-5. The EPS bits can only be written to while the EPDIS bit is set.
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Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Table 4-5. EEPROM Protection Address Range
4.3.2.6
EPS[2:0]
Address Offset Range
Protected Size
000
0x0FC0 – 0x0FFF
64 bytes
001
0x0F80 – 0x0FFF
128 bytes
010
0x0F40 – 0x0FFF
192 bytes
011
0x0F00 – 0x0FFF
256 bytes
100
0x0EC0 – 0x0FFF
320 bytes
101
0x0E80 – 0x0FFF
384 bytes
110
0x0E40 – 0x0FFF
448 bytes
111
0x0E00 – 0x0FFF
512 bytes
EEPROM Status Register (ESTAT)
The ESTAT register defines the operational status of the module.
Module Base + 0x0005
7
6
R
5
4
CCIF
CBEIF
PVIOL
ACCERR
0
0
3
2
1
0
0
BLANK
0
0
0
0
0
0
1
0
W
Reset
1
1
= Unimplemented or Reserved
Figure 4-9. EEPROM Status Register (ESTAT — Normal Mode)
Module Base + 0x0005
7
6
R
5
4
PVIOL
ACCERR
0
0
CCIF
CBEIF
3
2
0
BLANK
0
FAIL
W
Reset
1
1
0
0
0
0
= Unimplemented or Reserved
Figure 4-10. EEPROM Status Register (ESTAT — Special Mode)
CBEIF, PVIOL, and ACCERR are readable and writable, CCIF and BLANK are readable and not writable,
remaining bits read 0 and are not writable in normal mode. FAIL is readable and writable in special mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
183
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Table 4-6. ESTAT Field Descriptions
Field
Description
7
CBEIF
Command Buffer Empty Interrupt Flag — The CBEIF flag indicates that the address, data, and command
buffers are empty so that a new command write sequence can be started. The CBEIF flag is cleared by writing
a 1 to CBEIF. Writing a 0 to the CBEIF flag has no effect on CBEIF. Writing a 0 to CBEIF after writing an aligned
word to the EEPROM address space but before CBEIF is cleared will abort a command write sequence and
cause the ACCERR flag to be set. Writing a 0 to CBEIF outside of a command write sequence will not set the
ACCERR flag. The CBEIF flag is used together with the CBEIE bit in the ECNFG register to generate an interrupt
request (see Figure 4-24).
0 Buffers are full.
1 Buffers are ready to accept a new command.
6
CCIF
Command Complete Interrupt Flag — The CCIF flag indicates that there are no more commands pending. The
CCIF flag is cleared when CBEIF is clear and sets automatically upon completion of all active and pending
commands. The CCIF flag does not set when an active commands completes and a pending command is
fetched from the command buffer. Writing to the CCIF flag has no effect on CCIF. The CCIF flag is used together
with the CCIE bit in the ECNFG register to generate an interrupt request (see Figure 4-24).
0 Command in progress.
1 All commands are completed.
5
PVIOL
Protection Violation Flag — The PVIOL flag indicates an attempt was made to program or erase an address
in a protected area of the EEPROM memory during a command write sequence. The PVIOL flag is cleared by
writing a 1 to PVIOL. Writing a 0 to the PVIOL flag has no effect on PVIOL. While PVIOL is set, it is not possible
to launch a command or start a command write sequence.
0 No failure.
1 A protection violation has occurred.
4
ACCERR
Access Error Flag — The ACCERR flag indicates an illegal access has occurred to the EEPROM memory
caused by either a violation of the command write sequence (see Section 4.4.1.2, “Command Write Sequence”),
issuing an illegal EEPROM command (see Table 4-8), launching the sector erase abort command terminating a
sector erase operation early (see Section 4.4.2.5, “Sector Erase Abort Command”) or the execution of a CPU
STOP instruction while a command is executing (CCIF = 0). The ACCERR flag is cleared by writing a 1 to
ACCERR. Writing a 0 to the ACCERR flag has no effect on ACCERR. While ACCERR is set, it is not possible to
launch a command or start a command write sequence. If ACCERR is set by an erase verify operation, any
buffered command will not launch.
0 No access error detected.
1 Access error has occurred.
2
BLANK
Flag Indicating the Erase Verify Operation Status — When the CCIF flag is set after completion of an erase
verify command, the BLANK flag indicates the result of the erase verify operation. The BLANK flag is cleared by
the EEPROM module when CBEIF is cleared as part of a new valid command write sequence. Writing to the
BLANK flag has no effect on BLANK.
0 EEPROM block verified as not erased.
1 EEPROM block verified as erased.
1
FAIL
Flag Indicating a Failed EEPROM Operation — The FAIL flag will set if the erase verify operation fails
(EEPROM block verified as not erased). The FAIL flag is cleared by writing a 1 to FAIL. Writing a 0 to the FAIL
flag has no effect on FAIL.
0 EEPROM operation completed without error.
1 EEPROM operation failed.
MC9S12XHZ512 Data Sheet, Rev. 1.06
184
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.3.2.7
EEPROM Command Register (ECMD)
The ECMD register is the EEPROM command register.
Module Base + 0x0006
7
R
6
5
4
3
2
1
0
0
0
0
0
CMDB
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 4-11. EEPROM Command Register (ECMD)
All CMDB bits are readable and writable during a command write sequence while bit 7 reads 0 and is not
writable.
Table 4-7. ECMD Field Descriptions
Field
6:0
CMDB[6:0]
Description
EEPROM Command Bits — Valid EEPROM commands are shown in Table 4-8. Writing any command other
than those listed in Table 4-8 sets the ACCERR flag in the ESTAT register.
Table 4-8. Valid EEPROM Command List
4.3.2.8
CMDB[6:0]
Command
0x05
Erase Verify
0x20
Word Program
0x40
Sector Erase
0x41
Mass Erase
0x47
Sector Erase Abort
0x60
Sector Modify
RESERVED3
This register is reserved for factory testing and is not accessible.
Module Base + 0x0007
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 4-12. RESERVED3
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
185
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
All bits read 0 and are not writable.
EEPROM Address Registers (EADDR)
The EADDRHI and EADDRLO registers are the EEPROM address registers.
Module Base + 0x0008
R
7
6
5
4
3
0
0
0
0
0
0
0
0
0
0
2
1
0
EABHI
W
Reset
0
0
0
= Unimplemented or Reserved
Figure 4-13. EEPROM Address High Register (EADDRHI)
Module Base + 0x0009
7
6
5
4
R
3
2
1
0
0
0
0
0
EABLO
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 4-14. EEPROM Address Low Register (EADDRLO)
All EABHI and EABLO bits read 0 and are not writable in normal modes.
All EABHI and EABLO bits are readable and writable in special modes.
The MCU address bit AB0 is not stored in the EADDR registers since the EEPROM block is not byte
addressable.
4.3.2.9
EEPROM Data Registers (EDATA)
The EDATAHI and EDATALO registers are the EEPROM data registers.
Module Base + 0x000A
7
6
5
4
R
3
2
1
0
0
0
0
0
EDHI
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 4-15. EEPROM Data High Register (EDATAHI)
MC9S12XHZ512 Data Sheet, Rev. 1.06
186
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Module Base + 0x000B
7
6
5
4
R
3
2
1
0
0
0
0
0
EDLO
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 4-16. EEPROM Data Low Register (EDATALO)
All EDHI and EDLO bits read 0 and are not writable in normal modes.
All EDHI and EDLO bits are readable and writable in special modes.
4.4
4.4.1
Functional Description
EEPROM Command Operations
Write operations are used to execute program, erase, erase verify, sector erase abort, and sector modify
algorithms described in this section. The program, erase, and sector modify algorithms are controlled by
a state machine whose timebase, EECLK, is derived from the oscillator clock via a programmable divider.
The command register as well as the associated address and data registers operate as a buffer and a register
(2-stage FIFO) so that a second command along with the necessary data and address can be stored to the
buffer while the first command is still in progress. Buffer empty as well as command completion are
signalled by flags in the EEPROM status register with interrupts generated, if enabled.
The next sections describe:
1. How to write the ECLKDIV register
2. Command write sequences to program, erase, erase verify, sector erase abort, and sector modify
operations on the EEPROM memory
3. Valid EEPROM commands
4. Effects resulting from illegal EEPROM command write sequences or aborting EEPROM
operations
4.4.1.1
Writing the ECLKDIV Register
Prior to issuing any EEPROM command after a reset, the user is required to write the ECLKDIV register
to divide the oscillator clock down to within the 150 kHz to 200 kHz range. Since the program and erase
timings are also a function of the bus clock, the ECLKDIV determination must take this information into
account.
If we define:
• ECLK as the clock of the EEPROM timing control block
• Tbus as the period of the bus clock
• INT(x) as taking the integer part of x (e.g., INT(4.323)=4)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
187
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
then ECLKDIV register bits PRDIV8 and EDIV[5:0] are to be set as described in Figure 4-17.
For example, if the oscillator clock frequency is 950 kHz and the bus clock frequency is 10 MHz,
ECLKDIV bits EDIV[5:0] should be set to 0x04 (000100) and bit PRDIV8 set to 0. The resulting EECLK
frequency is then 190 kHz. As a result, the EEPROM program and erase algorithm timings are increased
over the optimum target by:
( 200 – 190 ) ⁄ 200 × 100 = 5%
If the oscillator clock frequency is 16 MHz and the bus clock frequency is 40 MHz, ECLKDIV bits
EDIV[5:0] should be set to 0x0A (001010) and bit PRDIV8 set to 1. The resulting EECLK frequency is
then 182 kHz. In this case, the EEPROM program and erase algorithm timings are increased over the
optimum target by:
( 200 – 182 ) ⁄ 200 × 100 = 9%
CAUTION
Program and erase command execution time will increase proportionally
with the period of EECLK. Because of the impact of clock synchronization
on the accuracy of the functional timings, programming or erasing the
EEPROM memory cannot be performed if the bus clock runs at less than 1
MHz. Programming or erasing the EEPROM memory with EECLK < 150
kHz should be avoided. Setting ECLKDIV to a value such that EECLK <
150 kHz can destroy the EEPROM memory due to overstress. Setting
ECLKDIV to a value such that (1/EECLK+Tbus) < 5 µs can result in
incomplete programming or erasure of the EEPROM memory cells.
If the ECLKDIV register is written, the EDIVLD bit is set automatically. If the EDIVLD bit is 0, the
ECLKDIV register has not been written since the last reset. If the ECLKDIV register has not been written
to, the EEPROM command loaded during a command write sequence will not execute and the ACCERR
flag in the ESTAT register will set.
MC9S12XHZ512 Data Sheet, Rev. 1.06
188
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Tbus < 1µs?
no
ALL COMMANDS IMPOSSIBLE
yes
PRDIV8 = 0 (reset)
oscillator_clock
>12.8 MHz?
no
yes
PRDIV8 = 1
PRDCLK = oscillator_clock/8 PRDCLK = oscillator_clock
PRDCLK[MHz]*(5+Tbus[µs])
an integer?
yes
no
EDIV[5:0]=INT(PRDCLK[MHz]*(5+Tbus[µs]))
EDIV[5:0]=PRDCLK[MHz]*(5+Tbus[µs])–1
TRY TO DECREASE Tbus EECLK = (PRDCLK)/(1+EDIV[5:0])
1/EECLK[MHz] + Tbus[ms] > 5
AND
EECLK > 0.15 MHz
?
yes
END
no
yes
EDIV[5:0] > 4?
no
ALL COMMANDS IMPOSSIBLE
Figure 4-17. Determination Procedure for PRDIV8 and EDIV Bits
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
189
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.1.2
Command Write Sequence
The EEPROM command controller is used to supervise the command write sequence to execute program,
erase, erase verify, sector erase abort, and sector modify algorithms.
Before starting a command write sequence, the ACCERR and PVIOL flags in the ESTAT register must be
clear (see Section 4.3.2.6, “EEPROM Status Register (ESTAT)”) and the CBEIF flag should be tested to
determine the state of the address, data and command buffers. If the CBEIF flag is set, indicating the
buffers are empty, a new command write sequence can be started. If the CBEIF flag is clear, indicating the
buffers are not available, a new command write sequence will overwrite the contents of the address, data
and command buffers.
A command write sequence consists of three steps which must be strictly adhered to with writes to the
EEPROM module not permitted between the steps. However, EEPROM register and array reads are
allowed during a command write sequence. The basic command write sequence is as follows:
1. Write to one address in the EEPROM memory.
2. Write a valid command to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the command.
The address written in step 1 will be stored in the EADDR registers and the data will be stored in the
EDATA registers. If the CBEIF flag in the ESTAT register is clear when the first EEPROM array write
occurs, the contents of the address and data buffers will be overwritten and the CBEIF flag will be set.
When the CBEIF flag is cleared, the CCIF flag is cleared on the same bus cycle by the EEPROM command
controller indicating that the command was successfully launched. For all command write sequences
except sector erase abort, the CBEIF flag will set four bus cycles after the CCIF flag is cleared indicating
that the address, data, and command buffers are ready for a new command write sequence to begin. For
sector erase abort operations, the CBEIF flag will remain clear until the operation completes. Except for
the sector erase abort command, a buffered command will wait for the active operation to be completed
before being launched. The sector erase abort command is launched when the CBEIF flag is cleared as part
of a sector erase abort command write sequence. Once a command is launched, the completion of the
command operation is indicated by the setting of the CCIF flag in the ESTAT register. The CCIF flag will
set upon completion of all active and buffered commands.
4.4.2
EEPROM Commands
Table 4-9 summarizes the valid EEPROM commands along with the effects of the commands on the
EEPROM block.
Table 4-9. EEPROM Command Description
ECMDB
Command
Function on EEPROM Memory
0x05
Erase
Verify
Verify all memory bytes in the EEPROM block are erased. If the EEPROM block is erased, the
BLANK flag in the ESTAT register will set upon command completion.
0x20
Program
0x40
Sector
Erase
Program a word (two bytes) in the EEPROM block.
Erase all four memory bytes in a sector of the EEPROM block.
MC9S12XHZ512 Data Sheet, Rev. 1.06
190
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Table 4-9. EEPROM Command Description
ECMDB
Command
Function on EEPROM Memory
0x41
Mass
Erase
Erase all memory bytes in the EEPROM block. A mass erase of the full EEPROM block is only
possible when EPOPEN and EPDIS bits in the EPROT register are set prior to launching the
command.
0x47
Sector Erase
Abort
Abort the sector erase operation. The sector erase operation will terminate according to a set
procedure. The EEPROM sector should not be considered erased if the ACCERR flag is set
upon command completion.
0x60
Sector
Modify
Erase all four memory bytes in a sector of the EEPROM block and reprogram the addressed
word.
CAUTION
An EEPROM word (2 bytes) must be in the erased state before being
programmed. Cumulative programming of bits within a word is not allowed.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
191
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.1
Erase Verify Command
The erase verify operation will verify that the EEPROM memory is erased.
An example flow to execute the erase verify operation is shown in Figure 4-18. The erase verify command
write sequence is as follows:
1. Write to an EEPROM address to start the command write sequence for the erase verify command.
The address and data written will be ignored.
2. Write the erase verify command, 0x05, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the erase verify
command.
After launching the erase verify command, the CCIF flag in the ESTAT register will set after the operation
has completed unless a new command write sequence has been buffered. The number of bus cycles
required to execute the erase verify operation is equal to the number of words in the EEPROM memory
plus 14 bus cycles as measured from the time the CBEIF flag is cleared until the CCIF flag is set. Upon
completion of the erase verify operation, the BLANK flag in the ESTAT register will be set if all addresses
in the EEPROM memory are verified to be erased. If any address in the EEPROM memory is not erased,
the erase verify operation will terminate and the BLANK flag in the ESTAT register will remain clear.
MC9S12XHZ512 Data Sheet, Rev. 1.06
192
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Read: ECLKDIV register
Clock Register
Written
Check
EDIVLD
Set?
yes
NOTE: ECLKDIV needs to
be set once after each reset.
no
Write: ECLKDIV register
Read: ESTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
ACCERR/
PVIOL
Set?
no
yes
1.
Write: EEPROM Address
and Dummy Data
2.
Write: ECMD register
Erase Verify Command 0x05
3.
Write: ESTAT register
Clear CBEIF 0x80
Write: ESTAT register
Clear ACCERR/PVIOL 0x30
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
Read: ESTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
Erase Verify
Status
BLANK
Set?
no
yes
EXIT EEPROM Memory
Erased
EXIT
EEPROM Memory
Not Erased
Figure 4-18. Example Erase Verify Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
193
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.2
Program Command
The program operation will program a previously erased word in the EEPROM memory using an
embedded algorithm.
An example flow to execute the program operation is shown in Figure 4-19. The program command write
sequence is as follows:
1. Write to an EEPROM block address to start the command write sequence for the program
command. The data written will be programmed to the address written.
2. Write the program command, 0x20, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the program
command.
If a word to be programmed is in a protected area of the EEPROM memory, the PVIOL flag in the ESTAT
register will set and the program command will not launch. Once the program command has successfully
launched, the CCIF flag in the ESTAT register will set after the program operation has completed unless a
new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
194
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Read: ECLKDIV register
Clock Register
Written
Check
EDIVLD
Set?
yes
NOTE: ECLKDIV needs to
be set once after each reset.
no
Write: ECLKDIV register
Read: ESTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
ACCERR/
PVIOL
Set?
no
Access Error and
Protection Violation
Check
1.
Write: EEPROM Address
and program Data
2.
Write: ECMD register
Program Command 0x20
3.
Write: ESTAT register
Clear CBEIF 0x80
yes
Write: ESTAT register
Clear ACCERR/PVIOL 0x30
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
Read: ESTAT register
Bit Polling for
Buffer Empty
Check
no
CBEIF
Set?
yes
Sequential
Programming
Decision
Next
Word?
yes
no
Read: ESTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 4-19. Example Program Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
195
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.3
Sector Erase Command
The sector erase operation will erase both words in a sector of EEPROM memory using an embedded
algorithm.
An example flow to execute the sector erase operation is shown in Figure 4-20. The sector erase command
write sequence is as follows:
1. Write to an EEPROM memory address to start the command write sequence for the sector erase
command. The EEPROM address written determines the sector to be erased while global address
bits [1:0] and the data written are ignored.
2. Write the sector erase command, 0x40, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the sector erase
command.
If an EEPROM sector to be erased is in a protected area of the EEPROM memory, the PVIOL flag in the
ESTAT register will set and the sector erase command will not launch. Once the sector erase command has
successfully launched, the CCIF flag in the ESTAT register will set after the sector erase operation has
completed unless a new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
196
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Read: ECLKDIV register
Clock Register
Written
Check
EDIVLD
Set?
yes
NOTE: ECLKDIV needs to
be set once after each reset.
no
Write: ECLKDIV register
Read: ESTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
ACCERR/
PVIOL
Set?
no
yes
1.
Write: EEPROM Sector Address
and Dummy Data
2.
Write: ECMD register
Sector Erase Command 0x40
3.
Write: ESTAT register
Clear CBEIF 0x80
Write: ESTAT register
Clear ACCERR/PVIOL 0x30
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
Read: ESTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 4-20. Example Sector Erase Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
197
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.4
Mass Erase Command
The mass erase operation will erase all addresses in an EEPROM block using an embedded algorithm.
An example flow to execute the mass erase operation is shown in Figure 4-21. The mass erase command
write sequence is as follows:
1. Write to an EEPROM memory address to start the command write sequence for the mass erase
command. The address and data written will be ignored.
2. Write the mass erase command, 0x41, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the mass erase
command.
If the EEPROM memory to be erased contains any protected area, the PVIOL flag in the ESTAT register
will set and the mass erase command will not launch. Once the mass erase command has successfully
launched, the CCIF flag in the ESTAT register will set after the mass erase operation has completed unless
a new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
198
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Read: ECLKDIV register
Clock Register
Written
Check
EDIVLD
Set?
yes
NOTE: ECLKDIV needs to
be set once after each reset.
no
Write: ECLKDIV register
Read: ESTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
ACCERR/
PVIOL
Set?
no
yes
1.
Write: EEPROM Address
and Dummy Data
2.
Write: ECMD register
Mass Erase Command 0x41
3.
Write: ESTAT register
Clear CBEIF 0x80
Write: ESTAT register
Clear ACCERR/PVIOL 0x30
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
Read: ESTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 4-21. Example Mass Erase Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
199
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.5
Sector Erase Abort Command
The sector erase abort operation will terminate the active sector erase or sector modify operation so that
other sectors in an EEPROM block are available for read and program operations without waiting for the
sector erase or sector modify operation to complete.
An example flow to execute the sector erase abort operation is shown in Figure 4-22. The sector erase abort
command write sequence is as follows:
1. Write to any EEPROM memory address to start the command write sequence for the sector erase
abort command. The address and data written are ignored.
2. Write the sector erase abort command, 0x47, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the sector erase abort
command.
If the sector erase abort command is launched resulting in the early termination of an active sector erase
or sector modify operation, the ACCERR flag will set once the operation completes as indicated by the
CCIF flag being set. The ACCERR flag sets to inform the user that the EEPROM sector may not be fully
erased and a new sector erase or sector modify command must be launched before programming any
location in that specific sector. If the sector erase abort command is launched but the active sector erase or
sector modify operation completes normally, the ACCERR flag will not set upon completion of the
operation as indicated by the CCIF flag being set. If the sector erase abort command is launched after the
sector modify operation has completed the sector erase step, the program step will be allowed to complete.
The maximum number of cycles required to abort a sector erase or sector modify operation is equal to four
EECLK periods (see Section 4.4.1.1, “Writing the ECLKDIV Register”) plus five bus cycles as measured
from the time the CBEIF flag is cleared until the CCIF flag is set.
NOTE
Since the ACCERR bit in the ESTAT register may be set at the completion
of the sector erase abort operation, a command write sequence is not
allowed to be buffered behind a sector erase abort command write sequence.
The CBEIF flag will not set after launching the sector erase abort command
to indicate that a command should not be buffered behind it. If an attempt is
made to start a new command write sequence with a sector erase abort
operation active, the ACCERR flag in the ESTAT register will be set. A new
command write sequence may be started after clearing the ACCERR flag, if
set.
NOTE
The sector erase abort command should be used sparingly since a sector
erase operation that is aborted counts as a complete program/erase cycle.
MC9S12XHZ512 Data Sheet, Rev. 1.06
200
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
Execute Sector Erase/Modify Command Flow
Read: ESTAT register
Bit Polling for
Command
Completion Check
CCIF
Set?
Erase
Abort
Needed?
no
yes
Sector Erase
Completed
no
yes
EXIT
1.
Write: Dummy EEPROM Address
and Dummy Data
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
2.
Write: ECMD register
Sector Erase Abort Cmd 0x47
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
3.
Write: ESTAT register
Clear CBEIF 0x80
Read: ESTAT register
Bit Polling for
Command
Completion Check
CCIF
Set?
no
yes
Access
Error Check
ACCERR
Set?
yes
Write: ESTAT register
Clear ACCERR 0x10
no
Sector Erase
or Modify
Completed
EXIT
Sector Erase
or Modify
Aborted
EXIT
Figure 4-22. Example Sector Erase Abort Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
201
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.6
Sector Modify Command
The sector modify operation will erase both words in a sector of EEPROM memory followed by a
reprogram of the addressed word using an embedded algorithm.
An example flow to execute the sector modify operation is shown in Figure 4-23. The sector modify
command write sequence is as follows:
1. Write to an EEPROM memory address to start the command write sequence for the sector modify
command. The EEPROM address written determines the sector to be erased and word to be
reprogrammed while byte address bit 0 is ignored.
2. Write the sector modify command, 0x60, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the sector erase
command.
If an EEPROM sector to be modified is in a protected area of the EEPROM memory, the PVIOL flag in
the ESTAT register will set and the sector modify command will not launch. Once the sector modify
command has successfully launched, the CCIF flag in the ESTAT register will set after the sector modify
operation has completed unless a new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
202
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
START
Read: ECLKDIV register
Clock Register
Written
Check
EDIVLD
Set?
yes
NOTE: ECLKDIV needs to
be set once after each reset.
no
Write: ECLKDIV register
Read: ESTAT register
Address, Data,
Command
Buffer Empty Check
CBEIF
Set?
no
yes
Access Error and
Protection Violation
Check
ACCERR/
PVIOL
Set?
no
yes
1.
Write: EEPROM Word Address
and program Data
2.
Write: ECMD register
Sector Modify Command 0x60
3.
Write: ESTAT register
Clear CBEIF 0x80
Write: ESTAT register
Clear ACCERR/PVIOL 0x30
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
NOTE: command write sequence
aborted by writing 0x00 to
ESTAT register.
Read: ESTAT register
Bit Polling for
Command Completion
Check
CCIF
Set?
no
yes
EXIT
Figure 4-23. Example Sector Modify Command Flow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
203
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.3
Illegal EEPROM Operations
The ACCERR flag will be set during the command write sequence if any of the following illegal steps are
performed, causing the command write sequence to immediately abort:
1. Writing to an EEPROM address before initializing the ECLKDIV register.
2. Writing a byte or misaligned word to a valid EEPROM address.
3. Starting a command write sequence while a sector erase abort operation is active.
4. Writing to any EEPROM register other than ECMD after writing to an EEPROM address.
5. Writing a second command to the ECMD register in the same command write sequence.
6. Writing an invalid command to the ECMD register.
7. Writing to an EEPROM address after writing to the ECMD register.
8. Writing to any EEPROM register other than ESTAT (to clear CBEIF) after writing to the ECMD
register.
9. Writing a 0 to the CBEIF flag in the ESTAT register to abort a command write sequence.
The ACCERR flag will not be set if any EEPROM register is read during a valid command write sequence.
The ACCERR flag will also be set if any of the following events occur:
1. Launching the sector erase abort command while a sector erase or sector modify operation is active
which results in the early termination of the sector erase or sector modify operation (see
Section 4.4.2.5, “Sector Erase Abort Command”).
2. The MCU enters stop mode and a command operation is in progress. The operation is aborted
immediately and any pending command is purged (see Section 4.5.2, “Stop Mode”).
If the EEPROM memory is read during execution of an algorithm (CCIF = 0), the read operation will
return invalid data and the ACCERR flag will not be set.
If the ACCERR flag is set in the ESTAT register, the user must clear the ACCERR flag before starting
another command write sequence (see Section 4.3.2.6, “EEPROM Status Register (ESTAT)”).
The PVIOL flag will be set after the command is written to the ECMD register during a command write
sequence if any of the following illegal operations are attempted, causing the command write sequence to
immediately abort:
1. Writing the program command if the address written in the command write sequence was in a
protected area of the EEPROM memory.
2. Writing the sector erase command if the address written in the command write sequence was in a
protected area of the EEPROM memory.
3. Writing the mass erase command to the EEPROM memory while any EEPROM protection is
enabled.
4. Writing the sector modify command if the address written in the command write sequence was in
a protected area of the EEPROM memory.
If the PVIOL flag is set in the ESTAT register, the user must clear the PVIOL flag before starting another
command write sequence (see Section 4.3.2.6, “EEPROM Status Register (ESTAT)”).
MC9S12XHZ512 Data Sheet, Rev. 1.06
204
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.5
4.5.1
Operating Modes
Wait Mode
If a command is active (CCIF = 0) when the MCU enters the wait mode, the active command and any
buffered command will be completed.
The EEPROM module can recover the MCU from wait mode if the CBEIF and CCIF interrupts are enabled
(see Section 4.8, “Interrupts”).
4.5.2
Stop Mode
If a command is active (CCIF = 0) when the MCU enters the stop mode, the operation will be aborted and,
if the operation is program, sector erase, mass erase, or sector modify, the EEPROM array data being
programmed or erased may be corrupted and the CCIF and ACCERR flags will be set. If active, the high
voltage circuitry to the EEPROM memory will immediately be switched off when entering stop mode.
Upon exit from stop mode, the CBEIF flag is set and any buffered command will not be launched. The
ACCERR flag must be cleared before starting a command write sequence (see Section 4.4.1.2, “Command
Write Sequence”).
NOTE
As active commands are immediately aborted when the MCU enters stop
mode, it is strongly recommended that the user does not use the STOP
instruction during program, sector erase, mass erase, or sector modify
operations.
4.5.3
Background Debug Mode
In background debug mode (BDM), the EPROT register is writable. If the MCU is unsecured, then all
EEPROM commands listed in Table 4-9 can be executed. If the MCU is secured and is in special single
chip mode, the only command available to execute is mass erase.
4.6
EEPROM Module Security
The EEPROM module does not provide any security information to the MCU. After each reset, the
security state of the MCU is a function of information provided by the Flash module (see the specific FTX
Block Guide).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
205
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.6.1
Unsecuring the MCU in Special Single Chip Mode using BDM
Before the MCU can be unsecured in special single chip mode, the EEPROM memory must be erased
using the following method :
• Reset the MCU into special single chip mode, delay while the erase test is performed by the BDM
secure ROM, send BDM commands to disable protection in the EEPROM module, and execute a
mass erase command write sequence to erase the EEPROM memory.
After the CCIF flag sets to indicate that the EEPROM mass operation has completed and assuming that the
Flash memory has also been erased, reset the MCU into special single chip mode. The BDM secure ROM
will verify that the Flash and EEPROM memory are erased and will assert the UNSEC bit in the BDM
status register. This BDM action will cause the MCU to override the Flash security state and the MCU will
be unsecured. Once the MCU is unsecured, BDM commands will be enabled and the Flash security byte
may be programmed to the unsecure state.
4.7
4.7.1
Resets
EEPROM Reset Sequence
On each reset, the EEPROM module executes a reset sequence to hold CPU activity while loading the
EPROT register from the EEPROM memory according to Table 4-1.
4.7.2
Reset While EEPROM Command Active
If a reset occurs while any EEPROM command is in progress, that command will be immediately aborted.
The state of a word being programmed or the sector / block being erased is not guaranteed.
4.8
Interrupts
The EEPROM module can generate an interrupt when all EEPROM command operations have completed,
when the EEPROM address, data, and command buffers are empty.
Table 4-10. EEPROM Interrupt Sources
Interrupt Source
Interrupt Flag
Local Enable
Global (CCR) Mask
EEPROM address, data, and command buffers empty
CBEIF
(ESTAT register)
CBEIE
(ECNFG register)
I Bit
All EEPROM commands completed
CCIF
(ESTAT register)
CCIE
(ECNFG register)
I Bit
NOTE
Vector addresses and their relative interrupt priority are determined at the
MCU level.
MC9S12XHZ512 Data Sheet, Rev. 1.06
206
Freescale Semiconductor
Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.8.1
Description of EEPROM Interrupt Operation
The logic used for generating interrupts is shown in Figure 4-24.
The EEPROM module uses the CBEIF and CCIF flags in combination with the CBIE and CCIE enable
bits to generate the EEPROM command interrupt request.
CBEIF
CBEIE
EEPROM Command Interrupt Request
CCIF
CCIE
Figure 4-24. EEPROM Interrupt Implementation
For a detailed description of the register bits, refer to Section 4.3.2.4, “EEPROM Configuration Register
(ECNFG)” and Section 4.3.2.6, “EEPROM Status Register (ESTAT)” .
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
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Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
MC9S12XHZ512 Data Sheet, Rev. 1.06
208
Freescale Semiconductor
Chapter 5
XGATE (S12XGATEV2)
Revision History
Version
Number
02.22
02.23
V03.24
5.1
Date
Author
Description of Changes
14 Dec
2005
19 Mar
2007
Updated code example
Internal updates
13 Feb
2009
- Minor corrections (5.3.1.4/5-220)
Introduction
The XGATE module is a peripheral co-processor that allows autonomous data transfers between the
MCU’s peripherals and the internal memories. It has a built in RISC core that is able to pre-process the
transferred data and perform complex communication protocols.
The XGATE module is intended to increase the MCU’s data throughput by lowering the S12X_CPU’s
interrupt load.
Figure 5-1 gives an overview on the XGATE architecture.
This document describes the functionality of the XGATE module, including:
• XGATE registers (Section 5.3, “Memory Map and Register Definition”)
• XGATE RISC core (Section 5.4.1, “XGATE RISC Core”)
• Hardware semaphores (Section 5.4.4, “Semaphores”)
• Interrupt handling (Section 5.5, “Interrupts”)
• Debug features (Section 5.6, “Debug Mode”)
• Security (Section 5.7, “Security”)
• Instruction set (Section 5.8, “Instruction Set”)
5.1.1
Glossary of Terms
XGATE Request
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
209
Chapter 5 XGATE (S12XGATEV2)
A service request from a peripheral module which is directed to the XGATE by the S12X_INT
module (see Figure 5-1).
XGATE Channel
The resources in the XGATE module (i.e. Channel ID number, Priority level, Service Request
Vector, Interrupt Flag) which are associated with a particular XGATE Request.
XGATE Channel ID
A 7-bit identifier associated with an XGATE channel. In S12X designs valid Channel IDs range
from $78 to $09.
XGATE Channel Interrupt
An S12X_CPU interrupt that is triggered by a code sequence running on the XGATE module.
XGATE Software Channel
Special XGATE channel that is not associated with any peripheral service request. A Software
Channel is triggered by its Software Trigger Bit which is implemented in the XGATE module.
XGATE Semaphore
A set of hardware flip-flops that can be exclusively set by either the S12X_CPU or the XGATE.
(see 5.4.4/5-231)
XGATE Thread
A code sequence which is executed by the XGATE’s RISC core after receiving an XGATE request.
XGATE Debug Mode
A special mode in which the XGATE’s RISC core is halted for debug purposes. This mode enables
the XGATE’s debug features (see 5.6/5-233).
XGATE Software Error
The XGATE is able to detect a number of error conditions caused by erratic software (see
5.4.5/5-232). These error conditions will cause the XGATE to seize program execution and flag an
Interrupt to the S12X_CPU.
Word
A 16 bit entity.
Byte
An 8 bit entity.
5.1.2
Features
The XGATE module includes these features:
• Data movement between various targets (i.e Flash, RAM, and peripheral modules)
• Data manipulation through built in RISC core
• Provides up to 112 XGATE channels
MC9S12XHZ512 Data Sheet, Rev. 1.06
210
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
•
•
•
5.1.3
— 104 hardware triggered channels
— 8 software triggered channels
Hardware semaphores which are shared between the S12X_CPU and the XGATE module
Able to trigger S12X_CPU interrupts upon completion of an XGATE transfer
Software error detection to catch erratic application code
Modes of Operation
There are four run modes on S12X devices.
• Run mode, wait mode, stop mode
The XGATE is able to operate in all of these three system modes. Clock activity will be
automatically stopped when the XGATE module is idle.
• Freeze mode (BDM active)
In freeze mode all clocks of the XGATE module may be stopped, depending on the module
configuration (see Section 5.3.1.1, “XGATE Control Register (XGMCTL)”).
5.1.4
Block Diagram
Figure Figure 5-1 shows a block diagram of the XGATE.
Peripheral Interrupts
XGATE
REQUESTS
XGATE
XGATE
INTERRUPTS
S12X_INT
Interrupt Flags
Semaphores
RISC Core
Software
Triggers
Data/Code
Software Triggers
Peripherals
S12X_DBG
S12X_MMC
Figure 5-1. XGATE Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
211
Chapter 5 XGATE (S12XGATEV2)
5.2
External Signal Description
The XGATE module has no external pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
212
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.3
Memory Map and Register Definition
This section provides a detailed description of address space and registers used by the XGATE module.
The memory map for the XGATE module is given below in Figure 5-2.The address listed for each register
is the sum of a base address and an address offset. The base address is defined at the SoC level and the
address offset is defined at the module level. Reserved registers read zero. Write accesses to the reserved
registers have no effect.
5.3.1
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Details of register bit and field function follow the register
diagrams, in bit order.
Register
Name
0x0000
XGMCTL
R
W
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
XGEM
XG
XG
XG
XGSSM
FRZM DBGM
FACTM
0x0002
R
XGMCHID W
XG
SWEIFM
XGIEM
7
6
5
4
XGE XGFRZ XGDBG XGSS
0
3
XG
FACT
2
0
1
0
XG
XGIE
SWEIF
XGCHID[6:0]
0x0003
R
Reserved W
0x0004
R
Reserved W
0x0005
R
Reserved W
0x0006
XGVBR
R
XGVBR[15:1]
W
0
= Unimplemented or Reserved
Figure 5-2. XGATE Register Summary (Sheet 1 of 3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
213
Chapter 5 XGATE (S12XGATEV2)
0x0008
XGIF
R
127
126
125
124
123
122
121
0
0
0
0
0
0
0
W
113
112
110
109
108
107
106
105
104
103
102
101
100
99
98
97
96
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
XGIF_4F XGIF_4E XGIF_4D XGIF_4C XGIF_4B XGIF_4A XGIF_49 XGIF_48 XGF _47 XGIF_46 XGIF_45 XGIF_44 XGIF_43 XGIF_42 XGIF_41 XGIF_40
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
R
W
XGIF_3F XGIF_3E XGIF_3D XGIF_3C XGIF_3B XGIF_3A XGIF_39 XGIF_38 XGF _37 XGIF_36 XGIF_35 XGIF_34 XGIF_33 XGIF_32 XGIF_31 XGIF_30
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
R
W
XGIF_2F XGIF_2E XGIF_2D XGIF_2C XGIF_2B XGIF_2A XGIF_29 XGIF_28 XGF _27 XGIF_26 XGIF_25 XGIF_24 XGIF_23 XGIF_22 XGIF_21 XGIF_20
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
R
W
XGIF_1F XGIF_1E XGIF_1D XGIF_1C XGIF_1B XGIF_1A XGIF_19 XGIF_18 XGF _17 XGIF_16 XGIF_15 XGIF_14 XGIF_13 XGIF_12 XGIF_11 XGIF_10
15
0x0016
XGIF
114
R
W
31
0x0014
XGIF
115
XGIF_5F XGIF_5E XGIF_5D XGIF_5C XGIF_5B XGIF_5A XGIF_59 XGIF_58 XGF_57 XGIF_56 XGIF_55 XGIF_54 XGIF_53 XGIF_52 XGIF_51 XGIF_50
47
0x0012
XGIF
116
R
W
Register
Name
0x0010
XGIF
117
XGIF_6F XGIF_6E XGIF_6D XGIF_6C XGIF_6B XGIF_6A XGIF_69 XGIF_68 XGF_67 XGIF_66 XGIF_65 XGIF_64 XGIF_63 XGIF_62 XGIF_61 XGIF_60
79
0x000E
XGIF
118
R
95
0x000C
XGIF
119
XGIF_78 XGF_77 XGIF_76 XGIF_75 XGIF_74 XGIF_73 XGIF_72 XGIF_71 XGIF_70
W
111
0x000A
XGIF
120
14
13
12
11
10
9
R
W
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
XGIF_0F XGIF_0E XGIF_0D XGIF_0C XGIF_0B XGIF_0A XGIF_09
= Unimplemented or Reserved
Figure 5-2. XGATE Register Summary (Sheet 2 of 3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
214
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
15
14
13
12
11
10
9
8
0x0018
R
XGSWTM W
0
0
0
0
0
0
0
0
0x001A
R
XGSEMM W
0
0
0
0
7
6
5
0
0
0
3
2
1
0
XGSWT[7:0]
XGSWTM[7:0]
0
4
XGSEM[7:0]
XGSEMM[7:0]
0x001C
R
Reserved W
0x001D
XGCCR
R
W
0x001E
XGPC
W
0
R
0
0
0
XGN XGZ
XGV XGC
XGPC
0x0020
R
Reserved W
0x0021
R
Reserved W
0x0022
XGR1
0x0024
XGR2
0x0026
XGR3
R
R
R
XGR3
W
W
0x002A
XGR5
W
0x002E
XGR7
XGR2
W
0x0028
XGR4
0x002C
XGR6
XGR1
W
R
XGR4
R
XGR5
R
XGR6
W
R
XGR7
W
= Unimplemented or Reserved
Figure 5-2. XGATE Register Summary (Sheet 3 of 3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
215
Chapter 5 XGATE (S12XGATEV2)
5.3.1.1
XGATE Control Register (XGMCTL)
All module level switches and flags are located in the module control register Figure 5-3.
Module Base +0x00000
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
XG
SSM
XG
FACTM
0
0
R
W
XGEM
Reset
0
XG
XG
FRZM DBGM
0
0
7
0
0
5
4
3
2
0
XG
XGIEM
SWEIFM
0
6
XGE
XGFRZ XGDBG XGSS XGFACT
0
0
0
0
0
0
1
0
XG
SWEIF
XGIE
0
0
= Unimplemented or Reserved
Figure 5-3. XGATE Control Register (XGMCTL)
Read: Anytime
Write: Anytime
Table 5-1. XGMCTL Field Descriptions (Sheet 1 of 3)
Field
Description
15
XGEM
XGE Mask — This bit controls the write access to the XGE bit. The XGE bit can only be set or cleared if a "1" is
written to the XGEM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGE in the same bus cycle
1 Enable write access to the XGE in the same bus cycle
14
XGFRZM
XGFRZ Mask — This bit controls the write access to the XGFRZ bit. The XGFRZ bit can only be set or cleared
if a "1" is written to the XGFRZM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGFRZ in the same bus cycle
1 Enable write access to the XGFRZ in the same bus cycle
13
XGDBGM
XGDBG Mask — This bit controls the write access to the XGDBG bit. The XGDBG bit can only be set or cleared
if a "1" is written to the XGDBGM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGDBG in the same bus cycle
1 Enable write access to the XGDBG in the same bus cycle
12
XGSSM
XGSS Mask — This bit controls the write access to the XGSS bit. The XGSS bit can only be set or cleared if a
"1" is written to the XGSSM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGSS in the same bus cycle
1 Enable write access to the XGSS in the same bus cycle
MC9S12XHZ512 Data Sheet, Rev. 1.06
216
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
Table 5-1. XGMCTL Field Descriptions (Sheet 2 of 3)
Field
11
XGFACTM
Description
XGFACT Mask — This bit controls the write access to the XGFACT bit. The XGFACT bit can only be set or
cleared if a "1" is written to the XGFACTM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGFACT in the same bus cycle
1 Enable write access to the XGFACT in the same bus cycle
9
XGSWEIF Mask — This bit controls the write access to the XGSWEIF bit. The XGSWEIF bit can only be cleared
XGSWEIFM if a "1" is written to the XGSWEIFM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGSWEIF in the same bus cycle
1 Enable write access to the XGSWEIF in the same bus cycle
8
XGIEM
XGIE Mask — This bit controls the write access to the XGIE bit. The XGIE bit can only be set or cleared if a "1"
is written to the XGIEM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGIE in the same bus cycle
1 Enable write access to the XGIE in the same bus cycle
7
XGE
XGATE Module Enable — This bit enables the XGATE module. If the XGATE module is disabled, pending
XGATE requests will be ignored. The thread that is executed by the RISC core while the XGE bit is cleared will
continue to run.
Read:
0 XGATE module is disabled
1 XGATE module is enabled
Write:
0 Disable XGATE module
1 Enable XGATE module
6
XGFRZ
Halt XGATE in Freeze Mode — The XGFRZ bit controls the XGATE operation in Freeze Mode (BDM active).
Read:
0 RISC core operates normally in Freeze (BDM active)
1 RISC core stops in Freeze Mode (BDM active)
Write:
0 Don’t stop RISC core in Freeze Mode (BDM active)
1 Stop RISC core in Freeze Mode (BDM active)
5
XGDBG
XGATE Debug Mode — This bit indicates that the XGATE is in Debug Mode (see Section 5.6, “Debug Mode”).
Debug Mode can be entered by Software Breakpoints (BRK instruction), Tagged or Forced Breakpoints (see
S12X_DBG Section), or by writing a "1" to this bit.
Read:
0 RISC core is not in Debug Mode
1 RISC core is in Debug Mode
Write:
0 Leave Debug Mode
1 Enter Debug Mode
Note: Freeze Mode and Software Error Interrupts have no effect on the XGDBG bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
217
Chapter 5 XGATE (S12XGATEV2)
Table 5-1. XGMCTL Field Descriptions (Sheet 3 of 3)
Field
Description
4
XGSS
XGATE Single Step — This bit forces the execution of a single instruction if the XGATE is in DEBUG Mode and
no software error has occurred (XGSWEIF cleared).
Read:
0 No single step in progress
1 Single step in progress
Write
0 No effect
1 Execute a single RISC instruction
Note: Invoking a Single Step will cause the XGATE to temporarily leave Debug Mode until the instruction has
been executed.
3
XGFACT
Fake XGATE Activity — This bit forces the XGATE to flag activity to the MCU even when it is idle. When it is set
the MCU will never enter system stop mode which assures that peripheral modules will be clocked during XGATE
idle periods
Read:
0 XGATE will only flag activity if it is not idle or in debug mode.
1 XGATE will always signal activity to the MCU.
Write:
0 Only flag activity if not idle or in debug mode.
1 Always signal XGATE activity.
1
XGSWEIF
XGATE Software Error Interrupt Flag — This bit signals a pending Software Error Interrupt. It is set if the RISC
core detects an error condition (see Section 5.4.5, “Software Error Detection”). The RISC core is stopped while
this bit is set. Clearing this bit will terminate the current thread and cause the XGATE to become idle.
Read:
0 Software Error Interrupt is not pending
1 Software Error Interrupt is pending if XGIE is set
Write:
0 No effect
1 Clears the XGSWEIF bit
0
XGIE
XGATE Interrupt Enable — This bit acts as a global interrupt enable for the XGATE module
Read:
0 All XGATE interrupts disabled
1 All XGATE interrupts enabled
Write:
0 Disable all XGATE interrupts
1 Enable all XGATE interrupts
MC9S12XHZ512 Data Sheet, Rev. 1.06
218
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.3.1.2
XGATE Channel ID Register (XGCHID)
The XGATE channel ID register (Figure 5-4) shows the identifier of the XGATE channel that is currently
active. This register will read “$00” if the XGATE module is idle. In debug mode this register can be used
to start and terminate threads (see Section 5.6.1, “Debug Features”).
Module Base +0x0002
7
R
6
5
4
3
0
2
1
0
0
0
0
XGCHID[6:0]
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 5-4. XGATE Channel ID Register (XGCHID)
Read: Anytime
Write: In Debug Mode
Table 5-2. XGCHID Field Descriptions
Field
Description
6–0
Request Identifier — ID of the currently active channel
XGCHID[6:0]
5.3.1.3
XGATE Vector Base Address Register (XGVBR)
The vector base address register (Figure 5-5 and Figure 5-6) determines the location of the XGATE vector
block.
Module Base +0x0006
15
14
13
12
11
10
9
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
XGVBR[15:1]
W
Reset
8
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 5-5. XGATE Vector Base Address Register (XGVBR)
Read: Anytime
Write: Only if the module is disabled (XGE = 0) and idle (XGCHID = $00))
Table 5-3. XGVBR Field Descriptions
Field
Description
15–1
Vector Base Address — The XGVBR register holds the start address of the vector block in the XGATE
XBVBR[15:1] memory map.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
219
Chapter 5 XGATE (S12XGATEV2)
5.3.1.4
XGATE Channel Interrupt Flag Vector (XGIF)
The interrupt flag vector (Figure 5-6) provides access to the interrupt flags bits of each channel. Each flag
may be cleared by writing a "1" to its bit location.
Module Base +0x0008
R
127
126
125
124
123
122
121
0
0
0
0
0
0
0
120
119
XGIF_78
XGF_77
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
111
110
109
108
107
106
105
104
103
102
101
100
99
98
97
96
W
Reset
R
W
Reset
R
W
Reset
R
W
Reset
R
W
Reset
R
W
Reset
R
W
Reset
R
W
Reset
XGIF_6F XGIF_6E XGIF_6D XGIF_6C XGIF_6B XGIF_6A XGIF_69 XGIF_68
XGF_67
118
117
116
115
114
113
112
XGIF_76 XGIF_75 XGIF_74 XGIF_73 XGIF_72 XGIF_71 XGIF_70
XGIF_66 XGIF_65 XGIF_64 XGIF_63 XGIF_62 XGIF_61 XGIF_60
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
XGIF_5F XGIF_5E XGIF_5D XGIF_5C XGIF_5B XGIF_5A XGIF_59 XGIF_58
XGF_57
XGIF_56 XGIF_55 XGIF_54 XGIF_53 XGIF_52 XGIF_51 XGIF_50
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
XGIF_4F XGIF_4E XGIF_4D XGIF_4C XGIF_4B XGIF_4A XGIF_49 XGIF_48 XGF _47 XGIF_46 XGIF_45 XGIF_44 XGIF_43 XGIF_42 XGIF_41 XGIF_40
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
XGIF_3F XGIF_3E XGIF_3D XGIF_3C XGIF_3B XGIF_3A XGIF_39 XGIF_38 XGF _37 XGIF_36 XGIF_35 XGIF_34 XGIF_33 XGIF_32 XGIF_31 XGIF_30
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
XGIF_2F XGIF_2E XGIF_2D XGIF_2C XGIF_2B XGIF_2A XGIF_29 XGIF_28 XGF _27 XGIF_26 XGIF_25 XGIF_24 XGIF_23 XGIF_22 XGIF_21 XGIF_20
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
XGIF_1F XGIF_1E XGIF_1D XGIF_1C XGIF_1B XGIF_1A XGIF_19 XGIF_18 XGF _17 XGIF_16 XGIF_15 XGIF_14 XGIF_13 XGIF_12 XGIF_11 XGIF_10
0
0
0
0
0
0
0
15
14
13
12
11
10
9
XGIF_0F XGIF_0E XGIF_0D XGIF_0C XGIF_0B XGIF_0A XGIF_09
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 5-6. XGATE Channel Interrupt Flag Vector (XGIF)
Read: Anytime
MC9S12XHZ512 Data Sheet, Rev. 1.06
220
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
Write: Anytime
Table 5-4. XGIV Field Descriptions
Field
Description
120–9
XGIF_78
XGIF_09
Channel Interrupt Flags — These bits signal pending channel interrupts. They can only be set by the RISC
core. Each flag can be cleared by writing a "1" to its bit location. Unimplemented interrupt flags will always read
"0". Refer to Section “Interrupts” of the SoC Guide for a list of implemented Interrupts.
Read:
0 Channel interrupt is not pending
1 Channel interrupt is pending if XGIE is set
Write:
0 No effect
1 Clears the interrupt flag
NOTE
Suggested Mnemonics for accessing the interrupt flag vector on a word
basis are:
XGIF_7F_70 (XGIF[127:112]),
XGIF_6F_60 (XGIF[111:96]),
XGIF_5F_50 (XGIF[95:80]),
XGIF_4F_40 (XGIF[79:64]),
XGIF_3F_30 (XGIF[63:48]),
XGIF_2F_20 (XGIF[47:32]),
XGIF_1F_10 (XGIF[31:16]),
XGIF_0F_00 (XGIF[15:0])
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
221
Chapter 5 XGATE (S12XGATEV2)
5.3.1.5
XGATE Software Trigger Register (XGSWT)
The eight software triggers of the XGATE module can be set and cleared through the XGATE software
trigger register (Figure 5-7). The upper byte of this register, the software trigger mask, controls the write
access to the lower byte, the software trigger bits. These bits can be set or cleared if a "1" is written to the
associated mask in the same bus cycle.
Module Base +0x00018
R
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
0
0
0
6
5
0
0
0
0
0
4
3
2
1
0
0
0
0
XGSWT[7:0]
XGSWTM[7:0]
W
Reset
7
0
0
0
0
0
Figure 5-7. XGATE Software Trigger Register (XGSWT)
Read: Anytime
Write: Anytime
Table 5-5. XGSWT Field Descriptions
Field
Description
15–8
Software Trigger Mask — These bits control the write access to the XGSWT bits. Each XGSWT bit can only
XGSWTM[7:0] be written if a "1" is written to the corresponding XGSWTM bit in the same access.
Read:
These bits will always read "0".
Write:
0 Disable write access to the XGSWT in the same bus cycle
1 Enable write access to the corresponding XGSWT bit in the same bus cycle
7–0
XGSWT[7:0]
Software Trigger Bits — These bits act as interrupt flags that are able to trigger XGATE software channels.
They can only be set and cleared by software.
Read:
0 No software trigger pending
1 Software trigger pending if the XGIE bit is set
Write:
0 Clear Software Trigger
1 Set Software Trigger
NOTE
The XGATE channel IDs that are associated with the eight software triggers
are determined on chip integration level. (see Section “Interrupts” of the Soc
Guide)
XGATE software triggers work like any peripheral interrupt. They can be
used as XGATE requests as well as S12X_CPU interrupts. The target of the
software trigger must be selected in the S12X_INT module.
MC9S12XHZ512 Data Sheet, Rev. 1.06
222
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.3.1.6
XGATE Semaphore Register (XGSEM)
The XGATE provides a set of eight hardware semaphores that can be shared between the S12X_CPU and
the XGATE RISC core. Each semaphore can either be unlocked, locked by the S12X_CPU or locked by
the RISC core. The RISC core is able to lock and unlock a semaphore through its SSEM and CSEM
instructions. The S12X_CPU has access to the semaphores through the XGATE semaphore register
(Figure 5-8). Refer to section Section 5.4.4, “Semaphores” for details.
Module Base +0x0001A
R
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
0
0
0
W
Reset
7
6
5
0
0
0
0
3
2
1
0
0
0
0
XGSEM[7:0]
XGSEMM[7:0]
0
4
0
0
0
0
0
Figure 5-8. XGATE Semaphore Register (XGSEM)
Read: Anytime
Write: Anytime (see Section 5.4.4, “Semaphores”)
Table 5-6. XGSEM Field Descriptions
Field
Description
15–8
Semaphore Mask — These bits control the write access to the XGSEM bits.
XGSEMM[7:0] Read:
These bits will always read "0".
Write:
0 Disable write access to the XGSEM in the same bus cycle
1 Enable write access to the XGSEM in the same bus cycle
7–0
XGSEM[7:0]
Semaphore Bits — These bits indicate whether a semaphore is locked by the S12X_CPU. A semaphore can
be attempted to be set by writing a "1" to the XGSEM bit and to the corresponding XGSEMM bit in the same
write access. Only unlocked semaphores can be set. A semaphore can be cleared by writing a "0" to the
XGSEM bit and a "1" to the corresponding XGSEMM bit in the same write access.
Read:
0 Semaphore is unlocked or locked by the RISC core
1 Semaphore is locked by the S12X_CPU
Write:
0 Clear semaphore if it was locked by the S12X_CPU
1 Attempt to lock semaphore by the S12X_CPU
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
223
Chapter 5 XGATE (S12XGATEV2)
5.3.1.7
XGATE Condition Code Register (XGCCR)
The XGCCR register (Figure 5-9) provides access to the RISC core’s condition code register.
Module Base +0x001D
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
XGN
XGZ
XGV
XGC
0
0
0
0
= Unimplemented or Reserved
Figure 5-9. XGATE Condition Code Register (XGCCR)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-7. XGCCR Field Descriptions
Field
Description
3
XGN
Sign Flag — The RISC core’s Sign flag
2
XGZ
Zero Flag — The RISC core’s Zero flag
1
XGV
Overflow Flag — The RISC core’s Overflow flag
0
XGC
Carry Flag — The RISC core’s Carry flag
MC9S12XHZ512 Data Sheet, Rev. 1.06
224
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.3.1.8
XGATE Program Counter Register (XGPC)
The XGPC register (Figure 5-10) provides access to the RISC core’s program counter.
Module Base +0x0001E
15
14
13
12
11
10
9
8
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGPC
W
Reset
0
0
0
0
0
0
0
0
Figure 5-10. XGATE Program Counter Register (XGPC)
Figure 5-11.
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-8. XGPC Field Descriptions
Field
15–0
XGPC[15:0]
5.3.1.9
Description
Program Counter — The RISC core’s program counter
XGATE Register 1 (XGR1)
The XGR1 register (Figure 5-12) provides access to the RISC core’s register 1.
Module Base +0x00022
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR1
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-12. XGATE Register 1 (XGR1)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-9. XGR1 Field Descriptions
Field
15–0
XGR1[15:0]
Description
XGATE Register 1 — The RISC core’s register 1
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
225
Chapter 5 XGATE (S12XGATEV2)
5.3.1.10
XGATE Register 2 (XGR2)
The XGR2 register (Figure 5-13) provides access to the RISC core’s register 2.
Module Base +0x00024
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR2
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-13. XGATE Register 2 (XGR2)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-10. XGR2 Field Descriptions
Field
15–0
XGR2[15:0]
5.3.1.11
Description
XGATE Register 2 — The RISC core’s register 2
XGATE Register 3 (XGR3)
The XGR3 register (Figure 5-14) provides access to the RISC core’s register 3.
Module Base +0x00026
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR3
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-14. XGATE Register 3 (XGR3)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-11. XGR3 Field Descriptions
Field
15–0
XGR3[15:0]
Description
XGATE Register 3 — The RISC core’s register 3
MC9S12XHZ512 Data Sheet, Rev. 1.06
226
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.3.1.12
XGATE Register 4 (XGR4)
The XGR4 register (Figure 5-15) provides access to the RISC core’s register 4.
Module Base +0x00028
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR4
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-15. XGATE Register 4 (XGR4)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-12. XGR4 Field Descriptions
Field
15–0
XGR4[15:0]
5.3.1.13
Description
XGATE Register 4 — The RISC core’s register 4
XGATE Register 5 (XGR5)
The XGR5 register (Figure 5-16) provides access to the RISC core’s register 5.
Module Base +0x0002A
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR5
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-16. XGATE Register 5 (XGR5)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-13. XGR5 Field Descriptions
Field
15–0
XGR5[15:0]
Description
XGATE Register 5 — The RISC core’s register 5
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
227
Chapter 5 XGATE (S12XGATEV2)
5.3.1.14
XGATE Register 6 (XGR6)
The XGR6 register (Figure 5-17) provides access to the RISC core’s register 6.
Module Base +0x0002C
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR6
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-17. XGATE Register 6 (XGR6)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-14. XGR6 Field Descriptions
Field
15–0
XGR6[15:0]
5.3.1.15
Description
XGATE Register 6 — The RISC core’s register 6
XGATE Register 7 (XGR7)
The XGR7 register (Figure 5-18) provides access to the RISC core’s register 7.
Module Base +0x0002E
15
14
13
12
11
10
9
8
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
XGR7
W
Reset
7
0
0
0
0
0
0
0
0
Figure 5-18. XGATE Register 7 (XGR7)
Read: In debug mode if unsecured
Write: In debug mode if unsecured
Table 5-15. XGR7 Field Descriptions
Field
15–0
XGR7[15:0]
Description
XGATE Register 7 — The RISC core’s register 7
MC9S12XHZ512 Data Sheet, Rev. 1.06
228
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
5.4
Functional Description
The core of the XGATE module is a RISC processor which is able to access the MCU’s internal memories
and peripherals (see Figure 5-1). The RISC processor always remains in an idle state until it is triggered
by an XGATE request. Then it executes a code sequence that is associated with the request and optionally
triggers an interrupt to the S12X_CPU upon completion. Code sequences are not interruptible. A new
XGATE request can only be serviced when the previous sequence is finished and the RISC core becomes
idle.
The XGATE module also provides a set of hardware semaphores which are necessary to ensure data
consistency whenever RAM locations or peripherals are shared with the S12X_CPU.
The following sections describe the components of the XGATE module in further detail.
5.4.1
XGATE RISC Core
The RISC core is a 16 bit processor with an instruction set that is well suited for data transfers, bit
manipulations, and simple arithmetic operations (see Section 5.8, “Instruction Set”).
It is able to access the MCU’s internal memories and peripherals without blocking these resources from
the S12X_CPU1. Whenever the S12X_CPU and the RISC core access the same resource, the RISC core
will be stalled until the resource becomes available again1.
The XGATE offers a high access rate to the MCU’s internal RAM. Depending on the bus load, the RISC
core can perform up to two RAM accesses per S12X_CPU bus cycle.
Bus accesses to peripheral registers or flash are slower. A transfer rate of one bus access per S12X_CPU
cycle can not be exceeded.
The XGATE module is intended to execute short interrupt service routines that are triggered by peripheral
modules or by software.
5.4.2
Programmer’s Model
Register Block
15
15
R7
R6
Program Counter
0
PC
0
0
15
R5
15
R4
15
R3
15
R2
15
R1(Variable Pointer)
15
15
0
0
0
Condition
Code
Register
NZVC
3 2 1 0
0
0
R0 = 0
0
Figure 5-19. Programmer’s Model
1. With the exception of PRR registers (see Section “S12X_MMC”).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
229
Chapter 5 XGATE (S12XGATEV2)
The programmer’s model of the XGATE RISC core is shown in Figure 5-19. The processor offers a set of
seven general purpose registers (R1 - R7), which serve as accumulators and index registers. An additional
eighth register (R0) is tied to the value “$0000”. Register R1 has an additional functionality. It is preloaded
with the initial variable pointer of the channel’s service request vector (see Figure 5-20). The initial content
of the remaining general purpose registers is undefined.
The 16 bit program counter allows the addressing of a 64 kbyte address space.
The condition code register contains four bits: the sign bit (S), the zero flag (Z), the overflow flag (V), and
the carry bit (C). The initial content of the condition code register is undefined.
5.4.3
Memory Map
The XGATE’s RISC core is able to access an address space of 64K bytes. The allocation of memory blocks
within this address space is determined on chip level. Refer to the S12X_MMC Section for a detailed
information.
The XGATE vector block assigns a start address and a variable pointer to each XGATE channel. Its
position in the XGATE memory map can be adjusted through the XGVBR register (see Section 5.3.1.3,
“XGATE Vector Base Address Register (XGVBR)”). Figure 5-20 shows the layout of the vector block.
Each vector consists of two 16 bit words. The first contains the start address of the service routine. This
value will be loaded into the program counter before a service routine is executed. The second word is a
pointer to the service routine’s variable space. This value will be loaded into register R1 before a service
routine is executed.
XGVBR
+$0000
unused
Code
+$0024
Channel $09 Initial Program Counter
Channel $09 Initial Variable Pointer
+$0028
Channel $0A Initial Program Counter
Variables
Channel $0A Initial Variable Pointer
+$002C
Channel $0B Initial Program Counter
Channel $0B Initial Variable Pointer
+$0030
Channel $0C Initial Program Counter
Code
Channel $0C Initial Variable Pointer
+$01E0
Channel $78 Initial Program Counter
Variables
Channel $78 Initial Variable Pointer
Figure 5-20. XGATE Vector Block
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Chapter 5 XGATE (S12XGATEV2)
5.4.4
Semaphores
The XGATE module offers a set of eight hardware semaphores. These semaphores provide a mechanism
to protect system resources that are shared between two concurrent threads of program execution; one
thread running on the S12X_CPU and one running on the XGATE RISC core.
Each semaphore can only be in one of the three states: “Unlocked”, “Locked by S12X_CPU”, and “Locked
by XGATE”. The S12X_CPU can check and change a semaphore’s state through the XGATE semaphore
register (XGSEM, see Section 5.3.1.6, “XGATE Semaphore Register (XGSEM)”). The RISC core does
this through its SSEM and CSEM instructions.
Figure 5-21 illustrates the valid state transitions.
%1 ⇒ XGSEM
%0 ⇒ XGSEM
SSEM Instruction
LOCKED BY
S12X_CPU
LOCKED BY
XGATE
M
SE
XG
EM
⇒
0
.
GS
%
EM str
X
r
⇒ o GS In
X M
1
%
⇒ E
1 SS
% nd
a
In CS
st E
ru M
ct
In SS
io
st E
n
ru M
ct
io
n
%1 ⇒ XGSEM
SSEM Instruction
CSEM Instruction
UNLOCKED
%0 ⇒ XGSEM
CSEM Instruction
Figure 5-21. Semaphore State Transitions
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Chapter 5 XGATE (S12XGATEV2)
Figure 5-22 gives an example of the typical usage of the XGATE hardware semaphores.
Two concurrent threads are running on the system. One is running on the S12X_CPU and the other is
running on the RISC core. They both have a critical section of code that accesses the same system resource.
To guarantee that the system resource is only accessed by one thread at a time, the critical code sequence
must be embedded in a semaphore lock/release sequence as shown.
S12X_CPU
.........
XGATE
.........
%1 ⇒ XGSEMx
SSEM
XGSEM ≡ %1?
BCC?
critical
code
sequence
critical
code
sequence
XGSEM ⇒ %0
CSEM
.........
.........
Figure 5-22. Algorithm for Locking and Releasing Semaphores
5.4.5
Software Error Detection
The XGATE module will immediately terminate program execution after detecting an error condition
caused by erratic application code. There are three error conditions:
• Execution of an illegal opcode
• Illegal vector or opcode fetches
• Illegal load or store accesses
All opcodes which are not listed in section Section 5.8, “Instruction Set” are illegal opcodes. Illegal vector
and opcode fetches as well as illegal load and store accesses are defined on chip level. Refer to the
S12X_MMC Section for a detailed information.
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5.5
5.5.1
Interrupts
Incoming Interrupt Requests
XGATE threads are triggered by interrupt requests which are routed to the XGATE module (see
S12X_INT Section). Only a subset of the MCU’s interrupt requests can be routed to the XGATE. Which
specific interrupt requests these are and which channel ID they are assigned to is documented in Section
“Interrupts” of the SoC Guide.
5.5.2
Outgoing Interrupt Requests
There are three types of interrupt requests which can be triggered by the XGATE module:
5. Channel interrupts
For each XGATE channel there is an associated interrupt flag in the XGATE interrupt flag vector
(XGIF, see Section 5.3.1.4, “XGATE Channel Interrupt Flag Vector (XGIF)”). These flags can be
set through the "SIF" instruction by the RISC core. They are typically used to flag an interrupt to
the S12X_CPU when the XGATE has completed one of its tasks.
6. Software triggers
Software triggers are interrupt flags, which can be set and cleared by software (see Section 5.3.1.5,
“XGATE Software Trigger Register (XGSWT)”). They are typically used to trigger XGATE tasks
by the S12X_CPU software. However these interrupts can also be routed to the S12X_CPU (see
S12X_INT Section) and triggered by the XGATE software.
7. Software error interrupt
The software error interrupt signals to the S12X_CPU the detection of an error condition in the
XGATE application code (see Section 5.4.5, “Software Error Detection”).
All XGATE interrupts can be disabled by the XGIE bit in the XGATE module control register (XGMCTL,
see Section 5.3.1.1, “XGATE Control Register (XGMCTL)”).
5.6
Debug Mode
The XGATE debug mode is a feature to allow debugging of application code.
5.6.1
Debug Features
In debug mode the RISC core will be halted and the following debug features will be enabled:
• Read and Write accesses to RISC core registers (XGCCR, XGPC, XGR1–XGR7)1
All RISC core registers can be modified. Leaving debug mode will cause the RISC core to continue
program execution with the modified register values.
1. Only possible if MCU is unsecured
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•
•
5.6.2
Single Stepping
Writing a "1" to the XGSS bit will call the RISC core to execute a single instruction. All RISC core
registers will be updated accordingly.
Write accesses to the XGCHID register
Three operations can be performed by writing to the XGCHID register:
– Change of channel ID
If a non-zero value is written to the XGCHID while a thread is active (XGCHID ≠ $00), then
the current channel ID will be changed without any influence on the program counter or the
other RISC core registers.
– Start of a thread
If a non-zero value is written to the XGCHID while the XGATE is idle (XGCHID = $00),
then the thread that is associated with the new channel ID will be executed upon leaving
debug mode.
– Termination of a thread
If zero is written to the XGCHID while a thread is active (XGCHID ≠ $00), then the current
thread will be terminated and the XGATE will become idle.
Entering Debug Mode
Debug mode can be entered in four ways:
1. Setting XGDBG to "1"
Writing a "1" to XGDBG and XGDBGM in the same write access causes the XGATE to enter
debug mode upon completion of the current instruction.
NOTE
After writing to the XGDBG bit the XGATE will not immediately enter
debug mode. Depending on the instruction that is executed at this time there
may be a delay of several clock cycles. The XGDBG will read "0" until
debug mode is entered.
2. Software breakpoints
XGATE programs which are stored in the internal RAM allow the use of software breakpoints. A
software breakpoint is set by replacing an instruction of the program code with the "BRK"
instruction.
As soon as the program execution reaches the "BRK" instruction, the XGATE enters debug mode.
Additionally a software breakpoint request is sent to the S12X_DBG module (see section 4.9 of
the S12X_DBG Section).
Upon entering debug mode, the program counter will point to the "BRK" instruction. The other
RISC core registers will hold the result of the previous instruction.
To resume program execution, the "BRK" instruction must be replaced by the original instruction
before leaving debug mode.
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3. Tagged Breakpoints
The S12X_DBG module is able to place tags on fetched opcodes. The XGATE is able to enter
debug mode right before a tagged opcode is executed (see section 4.9 of the S12X_DBG Section).
Upon entering debug mode, the program counter will point to the tagged instruction. The other
RISC core registers will hold the result of the previous instruction.
4. Forced Breakpoints
Forced breakpoints are triggered by the S12X_DBG module (see section 4.9 of the S12X_DBG
Section). When a forced breakpoint occurs, the XGATE will enter debug mode upon completion
of the current instruction.
5.6.3
Leaving Debug Mode
Debug mode can only be left by setting the XGDBG bit to "0". If a thread is active (XGCHID has not been
cleared in debug mode), program execution will resume at the value of XGPC.
5.7
Security
In order to protect XGATE application code on secured S12X devices, a few restrictions in the debug
features have been made. These are:
• Registers XGCCR, XGPC, and XGR1–XGR7 will read zero on a secured device
• Registers XGCCR, XGPC, and XGR1–XGR7 can not be written on a secured device
• Single stepping is not possible on a secured device
5.8
5.8.1
Instruction Set
Addressing Modes
For the ease of implementation the architecture is a strict Load/Store RISC machine, which means all
operations must have one of the eight general purpose registers R0 … R7 as their source as well their
destination.
All word accesses must work with a word aligned address, that is A[0] = 0!
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Chapter 5 XGATE (S12XGATEV2)
5.8.1.1
Naming Conventions
RD
RD.L
RD.H
RS, RS1, RS2
RS.L, RS1.L, RS2.L
RS.H, RS1.H, RS2.H
RB
RI
RI+
–RI
Destination register, allowed range is R0–R7
Low byte of the destination register, bits [7:0]
High byte of the destination register, bits [15:8]
Source register, allowed range is R0–R7
Low byte of the source register, bits [7:0]
High byte of the source register, bits[15:8]
Base register for indexed addressing modes, allowed
range is R0–R7
Offset register for indexed addressing modes with
register offset, allowed range is R0–R7
Offset register for indexed addressing modes with
register offset and post-increment,
Allowed range is R0–R7 (R0+ is equivalent to R0)
Offset register for indexed addressing modes with
register offset and pre-decrement,
Allowed range is R0–R7 (–R0 is equivalent to R0)
NOTE
Even though register R1 is intended to be used as a pointer to the variable
segment, it may be used as a general purpose data register as well.
Selecting R0 as destination register will discard the result of the instruction.
Only the condition code register will be updated
5.8.1.2
Inherent Addressing Mode (INH)
Instructions that use this addressing mode either have no operands or all operands are in internal XGATE
registers:.
Examples
BRK
RTS
5.8.1.3
Immediate 3-Bit Wide (IMM3)
Operands for immediate mode instructions are included in the instruction stream and are fetched into the
instruction queue along with the rest of the 16 bit instruction. The ’#’ symbol is used to indicate an
immediate addressing mode operand. This address mode is used for semaphore instructions.
Examples:
CSEM
SSEM
#1
#3
; Unlock semaphore 1
; Lock Semaphore 3
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5.8.1.4
Immediate 4 Bit Wide (IMM4)
The 4 bit wide immediate addressing mode is supported by all shift instructions.
RD = RD ∗ imm4
Examples:
LSL
LSR
5.8.1.5
R4,#1
R4,#3
; R4 = R4 << 1; shift register R4 by 1 bit to the left
; R4 = R4 >> 3; shift register R4 by 3 bits to the right
Immediate 8 Bit Wide (IMM8)
The 8 bit wide immediate addressing mode is supported by four major commands (ADD, SUB, LD, CMP).
RD = RD ∗ imm8
Examples:
ADDL
SUBL
LDH
CMPL
5.8.1.6
R1,#1
R2,#2
R3,#3
R4,#4
;
;
;
;
adds an 8 bit value to register R1
subtracts an 8 bit value from register R2
loads an 8 bit immediate into the high byte of Register R3
compares the low byte of register R4 with an immediate value
Immediate 16 Bit Wide (IMM16)
The 16 bit wide immediate addressing mode is a construct to simplify assembler code. Instructions which
offer this mode are translated into two opcodes using the eight bit wide immediate addressing mode.
RD = RD ∗ imm16
Examples:
LDW
ADD
5.8.1.7
R4,#$1234
R4,#$5678
; translated to LDL R4,#$34; LDH R4,#$12
; translated to ADDL R4,#$78; ADDH R4,#$56
Monadic Addressing (MON)
In this addressing mode only one operand is explicitly given. This operand can either be the source (f(RD)),
the target (RD = f()), or both source and target of the operation (RD = f(RD)).
Examples:
JAL
SIF
R1
R2
; PC = R1, R1 = PC+2
; Trigger IRQ associated with the channel number in R2.L
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Chapter 5 XGATE (S12XGATEV2)
5.8.1.8
Dyadic Addressing (DYA)
In this mode the result of an operation between two registers is stored in one of the registers used as
operands.
RD = RD ∗ RS is the general register to register format, with register RD being the first operand and RS
the second. RD and RS can be any of the 8 general purpose registers R0 … R7. If R0 is used as the
destination register, only the condition code flags are updated. This addressing mode is used only for shift
operations with a variable shift value
Examples:
LSL
LSR
5.8.1.9
R4,R5
R4,R5
; R4 = R4 << R5
; R4 = R4 >> R5
Triadic Addressing (TRI)
In this mode the result of an operation between two or three registers is stored into a third one.
RD = RS1 ∗ RS2 is the general format used in the order RD, RS1, RS1. RD, RS1, RS2 can be any of the
8 general purpose registers R0 … R7. If R0 is used as the destination register RD, only the condition code
flags are updated. This addressing mode is used for all arithmetic and logical operations.
Examples:
ADC
SUB
5.8.1.10
R5,R6,R7
R5,R6,R7
; R5 = R6 + R7 + Carry
; R5 = R6 - R7
Relative Addressing 9-Bit Wide (REL9)
A 9-bit signed word address offset is included in the instruction word. This addressing mode is used for
conditional branch instructions.
Examples:
BCC
BEQ
5.8.1.11
REL9
REL9
; PC = PC + 2 + (REL9 << 1)
; PC = PC + 2 + (REL9 << 1)
Relative Addressing 10-Bit Wide (REL10)
An 11-bit signed word address offset is included in the instruction word. This addressing mode is used for
the unconditional branch instruction.
Examples:
BRA
5.8.1.12
REL10
; PC = PC + 2 + (REL10 << 1)
Index Register plus Immediate Offset (IDO5)
(RS, #offset5) provides an unsigned offset from the base register.
Examples:
LDB
STW
R4,(R1,#offset)
R4,(R1,#offset)
; loads a byte from R1+offset into R4
; stores R4 as a word to R1+offset
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Chapter 5 XGATE (S12XGATEV2)
5.8.1.13
Index Register plus Register Offset (IDR)
For load and store instructions (RS, RI) provides a variable offset in a register.
Examples:
LDB
STW
5.8.1.14
R4,(R1,R2)
R4,(R1,R2)
; loads a byte from R1+R2 into R4
; stores R4 as a word to R1+R2
Index Register plus Register Offset with Post-increment (IDR+)
[RS, RI+] provides a variable offset in a register, which is incremented after accessing the memory. In case
of a byte access the index register will be incremented by one. In case of a word access it will be
incremented by two.
Examples:
LDB
STW
5.8.1.15
R4,(R1,R2+)
R4,(R1,R2+)
; loads a byte from R1+R2 into R4, R2+=1
; stores R4 as a word to R1+R2, R2+=2
Index Register plus Register Offset with Pre-decrement (–IDR)
[RS, -RI] provides a variable offset in a register, which is decremented before accessing the memory. In
case of a byte access the index register will be decremented by one. In case of a word access it will be
decremented by two.
Examples:
LDB
STW
5.8.2
R4,(R1,-R2)
R4,(R1,-R2)
; R2 -=1, loads a byte from R1+R2 into R4
; R2 -=2, stores R4 as a word to R1+R2
Instruction Summary and Usage
5.8.2.1
Load & Store Instructions
Any register can be loaded either with an immediate or from the address space using indexed addressing
modes.
LDL
LDW
RD,#IMM8
RD,(RB,RI)
; loads an immediate 8 bit value to the lower byte of RD
; loads data using RB+RI as effective address
LDB
RD,(RB, RI+)
; loads data using RB+RI as effective address
; followed by an increment of RI depending on
; the size of the operation
The same set of modes is available for the store instructions
STB
RS,(RB, RI)
; stores data using RB+RI as effective address
STW
RS,(RB, RI+)
; stores data using RB+RI as effective address
; followed by an increment of RI depending on
; the size of the operation.
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Chapter 5 XGATE (S12XGATEV2)
5.8.2.2
Logic and Arithmetic Instructions
All logic and arithmetic instructions support the 8 bit immediate addressing mode (IMM8: RD = RD ∗
#IMM8) and the triadic addressing mode (TRI: RD = RS1 ∗ RS2).
All arithmetic is considered as signed, sign, overflow, zero and carry flag will be updated. The carry will
not be affected for logical operations.
ADDL
ANDH
R2,#1
R4,#$FE
; increment R2
; R4.H = R4.H & $FE, clear lower bit of higher byte
ADD
SUB
R3,R4,R5
R3,R4,R5
; R3 = R4 + R5
; R3 = R4 - R5
AND
OR
R3,R4,R5
R3,R4,R5
; R3 = R4 & R5 logical AND on the whole word
; R3 = R4 | R5
5.8.2.3
Register – Register Transfers
This group comprises transfers from and to some special registers
TFR
R3,CCR
; transfers the condition code register to the low byte of
; register R3
Branch Instructions
The branch offset is +255 words or -256 words counted from the beginning of the next instruction. Since
instructions have a fixed 16 bit width, the branch offsets are word aligned by shifting the offset value by 2.
BEQ
label
; if Z flag = 1 branch to label
An unconditional branch allows a +511 words or -512 words branch distance.
BRA
5.8.2.4
label
Shift Instructions
Shift operations allow the use of a 4 bit wide immediate value to identify a shift width within a 16 bit word.
For shift operations a value of 0 does not shift at all, while a value of 15 shifts the register RD by 15 bits.
In a second form the shift value is contained in the bits 3:0 of the register RS.
Examples:
LSL
LSR
ASR
R4,#1
R4,#3
R4,R2
; R4 = R4 << 1; shift register R4 by 1 bit to the left
; R4 = R4 >> 3; shift register R4 by 3 bits to the right
; R4 = R4 >> R2;arithmetic shift register R4 right by the amount
;
of bits contained in R2[3:0].
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5.8.2.5
Bit Field Operations
This addressing mode is used to identify the position and size of a bit field for insertion or extraction. The
width and offset are coded in the lower byte of the source register 2, RS2. The content of the upper byte is
ignored. An offset of 0 denotes the right most position and a width of 0 denotes 1 bit. These instructions
are very useful to extract, insert, clear, set or toggle portions of a 16 bit word.
W4
O4
5
2
W4=3, O4=2
15
RS2
0
RS1
Bit Field Extract
Bit Field Insert
15
3
0
RD
Figure 5-23. Bit Field Addressing
BFEXT
5.8.2.6
R3,R4,R5 ; R5: W4 bits offset O4, will be extracted from R4 into R3
Special Instructions for DMA Usage
The XGATE offers a number of additional instructions for flag manipulation, program flow control and
debugging:
1. SIF: Set a channel interrupt flag
2. SSEM: Test and set a hardware semaphore
3. CSEM: Clear a hardware semaphore
4. BRK: Software breakpoint
5. NOP: No Operation
6. RTS: Terminate the current thread
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5.8.3
Cycle Notation
Table 5-16 show the XGATE access detail notation. Each code letter equals one XGATE cycle. Each letter
implies additional wait cycles if memories or peripherals are not accessible. Memories or peripherals are
not accessible if they are blocked by the S12X_CPU. In addition to this Peripherals are only accessible
every other XGATE cycle. Uppercase letters denote 16 bit operations. Lowercase letters denote 8 bit
operations. The XGATE is able to perform two bus or wait cycles per S12X_CPU cycle.
Table 5-16. Access Detail Notation
V — Vector fetch: always an aligned word read, lasts for at least one RISC core cycle
P — Program word fetch: always an aligned word read, lasts for at least one RISC core cycle
r — 8 bit data read: lasts for at least one RISC core cycle
R — 16 bit data read: lasts for at least one RISC core cycle
w — 8 bit data write: lasts for at least one RISC core cycle
W — 16 bit data write: lasts for at least one RISC core cycle
A — Alignment cycle: no read or write, lasts for zero or one RISC core cycles
f — Free cycle: no read or write, lasts for one RISC core cycles
Special Cases
PP/P — Branch: PP if branch taken, P if not
5.8.4
Thread Execution
When the RISC core is triggered by an interrupt request (see Figure 5-1) it first executes a vector fetch
sequence which performs three bus accesses:
1. A V-cycle to fetch the initial content of the program counter.
2. A V-cycle to fetch the initial content of the data segment pointer (R1).
3. A P-cycle to load the initial opcode.
Afterwards a sequence of instructions (thread) is executed which is terminated by an "RTS" instruction. If
further interrupt requests are pending after a thread has been terminated, a new vector fetch will be
performed. Otherwise the RISC core will idle until a new interrupt request is received. A thread can not be
interrupted by an interrupt request.
5.8.5
Instruction Glossary
This section describes the XGATE instruction set in alphabetical order.
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ADC
ADC
Add with Carry
Operation
RS1 + RS2 + C ⇒ RD
Adds the content of register RS1, the content of register RS2 and the value of the Carry bit using binary
addition and stores the result in the destination register RD. The Zero Flag is also carried forward from the
previous operation allowing 32 and more bit additions.
Example:
ADC
ADC
BCC
R6,R2,R2
R7,R3,R3 ; R7:R6 = R5:R4 + R3:R2
; conditional branch on 32 bit addition
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Set if bit 15 of the result is set; cleared otherwise.
Z:
Set if the result is $0000 and Z was set before this operation; cleared otherwise.
V:
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & RD[15]new | RS1[15] & RS2[15] & RD[15]new
C:
Set if there is a carry from bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & RD[15]new | RS2[15] & RD[15]new
Code and CPU Cycles
Source Form
ADC RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
0
0
1
1
RD
RS1
Cycles
RS2
1
1
P
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Chapter 5 XGATE (S12XGATEV2)
ADD
ADD
Add without Carry
Operation
RS1 + RS2 ⇒ RD
RD + IMM16 ⇒ RD (translates to ADDL RD, #IMM16[7:0]; ADDH RD, #[15:8])
Performs a 16 bit addition and stores the result in the destination register RD.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & RD[15]new | RS1[15] & RS2[15] & RD[15]new
Refer to ADDH instruction for #IMM16 operations.
Set if there is a carry from bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & RD[15]new | RS2[15] & RD[15]new
Refer to ADDH instruction for #IMM16 operations.
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
RS1
Cycles
ADD RD, RS1, RS2
TRI
0
0
0
1
1
RD
RS2
1
0
P
ADD RD, #IMM16
IMM8
1
1
1
0
0
RD
IMM16[7:0]
P
IMM8
1
1
1
0
1
RD
IMM16[15:8]
P
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ADDH
ADDH
Add Immediate 8 bit Constant
(High Byte)
Operation
RD + IMM8:$00 ⇒ RD
Adds the content of high byte of register RD and a signed immediate 8 bit constant using binary addition
and stores the result in the high byte of the destination register RD. This instruction can be used after an
ADDL for a 16 bit immediate addition.
Example:
ADDL
ADDH
R2,#LOWBYTE
R2,#HIGHBYTE
; R2 = R2 + 16 bit immediate
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old & IMM8[7] & RD[15]new | RD[15]old & IMM8[7] & RD[15]new
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RD[15]old & IMM8[7] | RD[15]old & RD[15]new | IMM8[7] & RD[15]new
Code and CPU Cycles
Source Form
ADDH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
1
0
1
RD
Cycles
IMM8
P
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245
Chapter 5 XGATE (S12XGATEV2)
ADDL
Add Immediate 8 bit Constant
(Low Byte)
ADDL
Operation
RD + $00:IMM8 ⇒ RD
Adds the content of register RD and an unsigned immediate 8 bit constant using binary addition and stores
the result in the destination register RD. This instruction must be used first for a 16 bit immediate addition
in conjunction with the ADDH instruction.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the 8 bit operation; cleared otherwise.
RD[15]old & RD[15]new
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RD[15]old & RD[15]new
Code and CPU Cycles
Source Form
ADDL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
1
0
0
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
246
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
AND
AND
Logical AND
Operation
RS1 & RS2 ⇒ RD
RD & IMM16 ⇒ RD (translates to ANDL RD, #IMM16[7:0]; ANDH RD, #IMM16[15:8])
Performs a bit wise logical AND of two 16 bit values and stores the result in the destination register RD.
Remark: There is no complement to the BITH and BITL functions. This can be imitated by using R0 as a
destination register. AND R0, RS1, RS2 performs a bit wise test without storing a result.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Refer to ANDH instruction for #IMM16 operations.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
AND RD, RS1, RS2
AND RD, #IMM16
Address
Mode
Machine Code
RS1
Cycles
TRI
0
0
0
1
0
RD
RS2
0
0
P
IMM8
1
0
0
0
0
RD
IMM16[7:0]
P
IMM8
1
0
0
0
1
RD
IMM16[15:8]
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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247
Chapter 5 XGATE (S12XGATEV2)
ANDH
Logical AND Immediate 8 bit Constant
(High Byte)
ANDH
Operation
RD.H & IMM8 ⇒ RD.H
Performs a bit wise logical AND between the high byte of register RD and an immediate 8 bit constant and
stores the result in the destination register RD.H. The low byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ANDH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
0
0
1
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
248
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
ANDL
Logical AND Immediate 8 bit Constant
(Low Byte)
ANDL
Operation
RD.L & IMM8 ⇒ RD.L
Performs a bit wise logical AND between the low byte of register RD and an immediate 8 bit constant and
stores the result in the destination register RD.L. The high byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 7 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ANDL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
0
0
0
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
249
Chapter 5 XGATE (S12XGATEV2)
ASR
ASR
Arithmetic Shift Right
Operation
n
b15
RD
C
n = RS or IMM4
Shifts the bits in register RD n positions to the right. The higher n bits of the register RD become filled
with the sign bit (RD[15]). The carry flag will be updated to the bit contained in RD[n-1] before the shift
for n > 0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, n is determined by the content of RS. n is considered to be 16 if the content of RS
is greater than 15.
CCR Effects
N
Z
V
C
∆
∆
0
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
Set if n > 0 and RD[n-1] = 1; if n = 0 unaffected.
Code and CPU Cycles
Source Form
ASR RD, #IMM4
ASR RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
0
0
1
P
0
0
0
1
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
250
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BCC
BCC
Branch if Carry Cleared
(Same as BHS)
Operation
If C = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Carry flag and branches if C = 0.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BCC REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
0
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
251
Chapter 5 XGATE (S12XGATEV2)
BCS
BCS
Branch if Carry Set
(Same as BLO)
Operation
If C = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Carry flag and branches if C = 1.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BCS REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
0
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
252
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BEQ
BEQ
Branch if Equal
Operation
If Z = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Zero flag and branches if Z = 1.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BEQ REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
1
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
253
Chapter 5 XGATE (S12XGATEV2)
BFEXT
BFEXT
Bit Field Extract
Operation
RS1[(o+w):o] ⇒ RD[w:0]; 0 ⇒ RD[15:(w+1)]
w = (RS2[7:4])
o = (RS2[3:0])
Extracts w+1 bits from register RS1 starting at position o and writes them right aligned into register RD.
The remaining bits in RD will be cleared. If (o+w) > 15 only bits [15:o] get extracted.
15
7
4
3
0
W4
15
O4
5
2
RS2
0
W4=3, O4=2
RS1
Bit Field Extract
15
3
0
0
RD
CCR Effects
N
Z
V
C
0
∆
0
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BFEXT RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
1
1
0
0
RD
RS1
Cycles
RS2
1
1
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
254
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BFFO
BFFO
Bit Field Find First One
Operation
FirstOne (RS) ⇒ RD;
Searches the first “1” in register RS (from MSB to LSB) and writes the bit position into the destination
register RD. The upper bits of RD are cleared. In case the content of RS is equal to $0000, RD will be
cleared and the carry flag will be set. This is used to distinguish a “1” in position 0 versus no “1” in the
whole RS register at all.
CCR Effects
N
Z
V
C
0
∆
0
∆
N:
Z:
V:
C:
1
0; cleared.
Set if the result is $0000; cleared otherwise.
0; cleared.
Set if RS = $00001; cleared otherwise.
Before executing the instruction
Code and CPU Cycles
Source Form
BFFO RD, RS
Address
Mode
DYA
Machine Code
0
0
0
0
1
RD
RS
Cycles
1
0
0
0
0
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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255
Chapter 5 XGATE (S12XGATEV2)
BFINS
BFINS
Bit Field Insert
Operation
RS1[w:0] ⇒ RD[(w+o):o];
w = (RS2[7:4])
o = (RS2[3:0])
Extracts w+1 bits from register RS1 starting at position 0 and writes them into register RD starting at
position o. The remaining bits in RD are not affected. If (o+w) > 15 the upper bits are ignored. Using R0
as a RS1, this command can be used to clear bits.
15
7
4
3
0
W4
O4
15
3
RS2
0
RS1
Bit Field Insert
15
5
2
0
W4=3, O4=2
RD
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BFINS RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
1
1
0
1
RD
RS1
Cycles
RS2
1
1
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
256
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BFINSI
BFINSI
Bit Field Insert and Invert
Operation
!RS1[w:0] ⇒ RD[w+o:o];
w = (RS2[7:4])
o = (RS2[3:0])
Extracts w+1 bits from register RS1 starting at position 0, inverts them and writes into register RD starting
at position o. The remaining bits in RD are not affected. If (o+w) > 15 the upper bits are ignored. Using
R0 as a RS1, this command can be used to set bits.
15
7
4
3
0
W4
O4
15
RS2
3
0
RS1
Inverted Bit Field Insert
15
5
2
W4=3, O4=2
0
RD
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BFINSI RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
1
1
1
0
RD
RS1
Cycles
RS2
1
1
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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257
Chapter 5 XGATE (S12XGATEV2)
BFINSX
BFINSX
Bit Field Insert and XNOR
Operation
!(RS1[w:0] ^ RD[w+o:o]) ⇒ RD[w+o:o];
w = (RS2[7:4])
o = (RS2[3:0])
Extracts w+1 bits from register RS1 starting at position 0, performs an XNOR with RD[w+o:o] and writes
the bits back io RD. The remaining bits in RD are not affected. If (o+w) > 15 the upper bits are ignored.
Using R0 as a RS1, this command can be used to toggle bits.
15
7
4
3
0
W4
O4
15
RS2
3
0
RS1
Bit Field Insert XNOR
15
5
2
W4=3, O4=2
0
RD
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BFINSX RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
1
1
1
1
RD
RS1
Cycles
RS2
1
1
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
258
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BGE
BGE
Branch if Greater than or Equal to Zero
Operation
If N ^ V = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare signed numbers.
Branch if RS1 ≥ RS2:
SUB
BGE
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BGE REL9
Address
Mode
REL9
Machine Code
0
0
1
1
0
1
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
259
Chapter 5 XGATE (S12XGATEV2)
BGT
BGT
Branch if Greater than Zero
Operation
If Z | (N ^ V) = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare signed numbers.
Branch if RS1 > RS2:
SUB
BGE
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BGT REL9
Address
Mode
REL9
Machine Code
0
0
1
1
1
0
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
260
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BHI
BHI
Branch if Higher
Operation
If C | Z = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare unsigned numbers.
Branch if RS1 > RS2:
SUB
BHI
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BHI REL9
Address
Mode
REL9
Machine Code
0
0
1
1
0
0
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
261
Chapter 5 XGATE (S12XGATEV2)
BHS
BHS
Branch if Higher or Same
(Same as BCC)
Operation
If C = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare unsigned numbers.
Branch if RS1 ≥ RS2:
SUB
BHS
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BHS REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
0
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
262
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BITH
BITH
Bit Test Immediate 8 bit Constant
(High Byte)
Operation
RD.H & IMM8 ⇒ NONE
Performs a bit wise logical AND between the high byte of register RD and an immediate 8 bit constant.
Only the condition code flags get updated, but no result is written back
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BITH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
0
1
1
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
263
Chapter 5 XGATE (S12XGATEV2)
BITL
BITL
Bit Test Immediate 8 bit Constant
(Low Byte)
Operation
RD.L & IMM8 ⇒ NONE
Performs a bit wise logical AND between the low byte of register RD and an immediate 8 bit constant.
Only the condition code flags get updated, but no result is written back.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 7 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
BITL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
0
1
0
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
264
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BLE
BLE
Branch if Less or Equal to Zero
Operation
If Z | (N ^ V) = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare signed numbers.
Branch if RS1 ≤ RS2:
SUB
BLE
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BLE REL9
Address
Mode
REL9
Machine Code
0
0
1
1
1
0
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
265
Chapter 5 XGATE (S12XGATEV2)
BLO
BLO
Branch if Carry Set
(Same as BCS)
Operation
If C = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare unsigned numbers.
Branch if RS1 < RS2:
SUB
BLO
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BLO REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
0
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
266
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BLS
BLS
Branch if Lower or Same
Operation
If C | Z = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare unsigned numbers.
Branch if RS1 ≤ RS2:
SUB
BLS
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BLS REL9
Address
Mode
REL9
Machine Code
0
0
1
1
0
0
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
267
Chapter 5 XGATE (S12XGATEV2)
BLT
BLT
Branch if Lower than Zero
Operation
If N ^ V = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Branch instruction to compare signed numbers.
Branch if RS1 < RS2:
SUB
BLT
R0,RS1,RS2
REL9
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BLT REL9
Address
Mode
REL9
Machine Code
0
0
1
1
0
1
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
268
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BMI
BMI
Branch if Minus
Operation
If N = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Sign flag and branches if N = 1.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BMI REL9
Address
Mode
REL9
Machine Code
0
0
1
0
1
0
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
269
Chapter 5 XGATE (S12XGATEV2)
BNE
BNE
Branch if Not Equal
Operation
If Z = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Zero flag and branches if Z = 0.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BNE REL9
Address
Mode
REL9
Machine Code
0
0
1
0
0
1
0
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
270
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BPL
BPL
Branch if Plus
Operation
If N = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Sign flag and branches if N = 0.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BPL REL9
Address
Mode
REL9
Machine Code
0
0
1
0
1
0
0
Cycles
REL9
PP/P
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Chapter 5 XGATE (S12XGATEV2)
BRA
BRA
Branch Always
Operation
PC + $0002 + (REL10 << 1) ⇒ PC
Branches always
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BRA REL10
Address
Mode
REL10
Machine Code
0
0
1
1
1
1
Cycles
REL10
PP
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Chapter 5 XGATE (S12XGATEV2)
BRK
BRK
Break
Operation
Put XGATE into Debug Mode (see Section 5.6.2, “Entering Debug Mode”)and signals a Software
breakpoint to the S12X_DBG module (see section 4.9 of the S12X_DBG Section).
NOTE
It is not possible to single step over a BRK instruction. This instruction does
not advance the program counter.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BRK
Address
Mode
INH
Machine Code
0
0
0
0
0
0
0
0
0
0
Cycles
0
0
0
0
0
0
PAff
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Chapter 5 XGATE (S12XGATEV2)
BVC
BVC
Branch if Overflow Cleared
Operation
If V = 0, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Overflow flag and branches if V = 0.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BVC REL9
Address
Mode
REL9
Machine Code
0
0
1
0
1
1
0
Cycles
REL9
PP/P
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Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
BVS
BVS
Branch if Overflow Set
Operation
If V = 1, then PC + $0002 + (REL9 << 1) ⇒ PC
Tests the Overflow flag and branches if V = 1.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
BVS REL9
Address
Mode
REL9
Machine Code
0
0
1
0
1
1
1
Cycles
REL9
PP/P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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275
Chapter 5 XGATE (S12XGATEV2)
CMP
CMP
Compare
Operation
RS1 – RS2
⇒ NONE (translates to SUB R0, RS1, RS2)
RD – IMM16 ⇒ NONE (translates to CMPL RD, #IMM16[7:0]; CPCH RD, #IMM16[15:8])
Subtracts two 16 bit values and discards the result.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & result[15] | RS1[15] & RS2[15] & result[15]
RD[15] & IMM16[15] & result[15] | RD[15] & IMM16[15] & result[15]
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & result[15] | RS2[15] & result[15]
RD[15] & IMM16[15] | RD[15] & result[15] | IMM16[15] & result[15]
Code and CPU Cycles
Source Form
CMP RS1, RS2
CMP RS, #IMM16
Address
Mode
Machine Code
0
0
0
RS1
Cycles
TRI
0
0
0
1
1
RS2
0
0
P
IMM8
1
1
0
1
0
RS
IMM16[7:0]
P
IMM8
1
1
0
1
1
RS
IMM16[15:8]
P
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Chapter 5 XGATE (S12XGATEV2)
CMPL
Compare Immediate 8 bit Constant
(Low Byte)
CMPL
Operation
RS.L – IMM8 ⇒ NONE, only condition code flags get updated
Subtracts the 8 bit constant IMM8 contained in the instruction code from the low byte of the source register
RS.L using binary subtraction and updates the condition code register accordingly.
Remark: There is no equivalent operation using triadic addressing. Comparing the values of two registers
can be performed by using the subtract instruction with R0 as destination register.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 7 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
Set if a two´s complement overflow resulted from the 8 bit operation; cleared otherwise.
RS[7] & IMM8[7] & result[7] | RS[7] & IMM8[7] & result[7]
Set if there is a carry from the Bit 7 to Bit 8 of the result; cleared otherwise.
RS[7] & IMM8[7] | RS[7] & result[7] | IMM8[7] & result[7]
Code and CPU Cycles
Source Form
CMPL RS, #IMM8
Address
Mode
IMM8
Machine Code
1
1
0
1
0
RS
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
COM
COM
One’s Complement
Operation
~RS ⇒ RD (translates to XNOR RD, R0, RS)
~RD ⇒ RD (translates to XNOR RD, R0, RD)
Performs a one’s complement on a general purpose register.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
Cycles
COM RD, RS
TRI
0
0
0
1
0
RD
0
0
0
RS
1
1
P
COM RD
TRI
0
0
0
1
0
RD
0
0
0
RD
1
1
P
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Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
CPC
CPC
Compare with Carry
Operation
RS2 – RS1 - C ⇒ NONE (translates to SBC R0, RS1, RS2)
Subtracts the carry bit and the content of register RS2 from the content of register RS1 using binary
subtraction and discards the result.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & result[15] | RS1[15] & RS2[15] & result[15]
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & result[15] | RS2[15] & result[15]
Code and CPU Cycles
Source Form
CPC RS1, RS2
Address
Mode
TRI
Machine Code
0
0
0
1
1
0
0
0
RS1
Cycles
RS2
0
1
P
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Chapter 5 XGATE (S12XGATEV2)
CPCH
CPCH
Compare Immediate 8 bit Constant with
Carry (High Byte)
Operation
RS.H - IMM8 - C ⇒ NONE, only condition code flags get updated
Subtracts the carry bit and the 8 bit constant IMM8 contained in the instruction code from the high byte of
the source register RD using binary subtraction and updates the condition code register accordingly. The
carry bit and Zero bits are taken into account to allow a 16 bit compare in the form of
CMPL
CPCH
BCC
R2,#LOWBYTE
R2,#HIGHBYTE
; branch condition
Remark: There is no equivalent operation using triadic addressing. Comparing the values of two registers
can be performed by using the subtract instruction with R0 as destination register.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $00 and Z was set before this operation; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS[15] & IMM8[7] & result[15] | RS[15] & IMM8[7] & result[15]
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RS[15] & IMM8[7] | RS[15] & result[15] | IMM8[7] & result[15]
Code and CPU Cycles
Source Form
CPCH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
0
1
1
RS
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
CSEM
CSEM
Clear Semaphore
Operation
Unlocks a semaphore that was locked by the RISC core.
In monadic address mode, bits RS[2:0] select the semaphore to be cleared.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
Cycles
CSEM #IMM3
IMM3
0
0
0
0
0
IMM3
1
1
1
1
0
0
0
0
PA
CSEM RS
MON
0
0
0
0
0
RS
1
1
1
1
0
0
0
1
PA
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Chapter 5 XGATE (S12XGATEV2)
CSL
CSL
Logical Shift Left with Carry
Operation
n
C
RD
C
C
C
C
n bits
n = RS or IMM4
Shifts the bits in register RD n positions to the left. The lower n bits of the register RD become filled with
the carry flag. The carry flag will be updated to the bit contained in RD[16-n] before the shift for n > 0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, n is determined by the content of RS. n is considered to be 16 if the content of RS
is greater than 15.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
Set if n > 0 and RD[16-n] = 1; if n = 0 unaffected.
Code and CPU Cycles
Source Form
CSL RD, #IMM4
CSL RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
0
1
0
P
0
0
1
0
P
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Chapter 5 XGATE (S12XGATEV2)
CSR
CSR
Logical Shift Right with Carry
Operation
n
C
C
C
C
RD
C
n bits
n = RS or IMM4
Shifts the bits in register RD n positions to the right. The higher n bits of the register RD become filled
with the carry flag. The carry flag will be updated to the bit contained in RD[n-1] before the shift for n > 0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, n is determined by the content of RS. n is considered to be 16 if the content of RS
is greater than 15.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
Set if n > 0 and RD[n-1] = 1; if n = 0 unaffected.
Code and CPU Cycles
Source Form
CSR RD, #IMM4
CSR RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
0
1
1
P
0
0
1
1
P
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Chapter 5 XGATE (S12XGATEV2)
JAL
JAL
Jump and Link
Operation
PC + $0002 ⇒ RD; RD ⇒ PC
Jumps to the address stored in RD and saves the return address in RD.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
JAL RD
Address
Mode
MON
Machine Code
0
0
0
0
0
RD
1
1
Cycles
1
1
0
1
1
0
PP
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Chapter 5 XGATE (S12XGATEV2)
LDB
LDB
Load Byte from Memory
(Low Byte)
Operation
M[RB, #OFFS5 ⇒ RD.L; $00 ⇒ RD.H
M[RB, RI] ⇒ RD.L; $00 ⇒ RD.H
M[RB, RI] ⇒ RD.L; $00 ⇒ RD.H; RI+1 ⇒ RI;1
RI-1 ⇒ RI; M[RS, RI] ⇒ RD.L; $00 ⇒ RD.H
Loads a byte from memory into the low byte of register RD. The high byte is cleared.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
LDB RD, (RB, #OFFS5)
Address
Mode
Machine Code
Cycles
IDO5
0
1
0
0
0
RD
RB
OFFS5
Pr
LDB RD, (RS, RI)
IDR
0
1
1
0
0
RD
RB
RI
0
0
Pr
LDB RD, (RS, RI+)
IDR+
0
1
1
0
0
RD
RB
RI
0
1
Pr
LDB RD, (RS, -RI)
-IDR
0
1
1
0
0
RD
RB
RI
1
0
Pr
1.If the same general purpose register is used as index (RI) and destination register (RD), the content of the register will not
be incremented after the data move: M[RB, RI] ⇒ RD.L; $00 ⇒ RD.H
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 5 XGATE (S12XGATEV2)
LDH
LDH
Load Immediate 8 bit Constant
(High Byte)
Operation
IMM8 ⇒ RD.H;
Loads an eight bit immediate constant into the high byte of register RD. The low byte is not affected.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
LDH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
1
1
1
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
LDL
LDL
Load Immediate 8 bit Constant
(Low Byte)
Operation
IMM8 ⇒ RD.L; $00 ⇒ RD.H
Loads an eight bit immediate constant into the low byte of register RD. The high byte is cleared.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
LDL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
1
1
0
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
LDW
LDW
Load Word from Memory
Operation
M[RB, #OFFS5] ⇒ RD
M[RB, RI] ⇒ RD
M[RB, RI] ⇒ RD; RI+2 ⇒ RI1
RI-2 ⇒ RI; M[RS, RI] ⇒ RD
IMM16 ⇒ RD (translates to LDL RD, #IMM16[7:0]; LDH RD, #IMM16[15:8])
Loads a 16 bit value into the register RD.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
LDW RD, (RB, #OFFS5)
Address
Mode
Machine Code
Cycles
IDO5
0
1
0
0
1
RD
RB
OFFS5
PR
LDW RD, (RB, RI)
IDR
0
1
1
0
1
RD
RB
RI
0
0
PR
LDW RD, (RB, RI+)
IDR+
0
1
1
0
1
RD
RB
RI
0
1
PR
LDW RD, (RB, -RI)
-IDR
0
1
1
0
1
RD
RB
RI
1
0
PR
LDW RD, #IMM16
IMM8
1
1
1
1
0
RD
IMM16[7:0]
P
IMM8
1
1
1
1
1
RD
IMM16[15:8]
P
1. If the same general purpose register is used as index (RI) and destination register (RD), the content of the register will not be
incremented after the data move: M[RB, RI] ⇒ RD
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 5 XGATE (S12XGATEV2)
LSL
LSL
Logical Shift Left
Operation
n
C
RD
0
0
0
0
n bits
n = RS or IMM4
Shifts the bits in register RD n positions to the left. The lower n bits of the register RD become filled with
zeros. The carry flag will be updated to the bit contained in RD[16-n] before the shift for n > 0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, n is determined by the content of RS. n is considered to be 16 if the content of RS
is greater than 15.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
Set if n > 0 and RD[16-n] = 1; if n = 0 unaffected.
Code and CPU Cycles
Source Form
LSL RD, #IMM4
LSL RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
1
0
0
P
0
1
0
0
P
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Chapter 5 XGATE (S12XGATEV2)
LSR
LSR
Logical Shift Right
Operation
n
0
0
0
0
RD
C
n bits
n = RS or IMM4
Shifts the bits in register RD n positions to the right. The higher n bits of the register RD become filled
with zeros. The carry flag will be updated to the bit contained in RD[n-1] before the shift for n > 0.
n can range from 0 to 16.
In immediate address mode, n is determined by the operand IMM4. n is considered to be 16 in IMM4 is
equal to 0.
In dyadic address mode, n is determined by the content of RS. n is considered to be 16 if the content of RS
is greater than 15.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old ^ RD[15]new
Set if n > 0 and RD[n-1] = 1; if n = 0 unaffected.
Code and CPU Cycles
Source Form
LSR RD, #IMM4
LSR RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
1
0
1
P
0
1
0
1
P
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Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
MOV
MOV
Move Register Content
Operation
RS ⇒ RD (translates to OR RD, R0, RS)
Copies the content of RS to RD.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
MOV RD, RS
Address
Mode
TRI
Machine Code
0
0
0
1
0
RD
0
0
Cycles
0
RS
1
0
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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291
Chapter 5 XGATE (S12XGATEV2)
NEG
NEG
Two’s Complement
Operation
–RS ⇒ RD (translates to SUB RD, R0, RS)
–RD ⇒ RD (translates to SUB RD, R0, RD)
Performs a two’s complement on a general purpose register.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS[15] & RD[15]new
Set if there is a carry from the bit 15 of the result; cleared otherwise
RS[15] | RD[15]new
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
Cycles
NEG RD, RS
TRI
0 0 0 1 1
RD
0 0 0
RS
0 0
P
NEG RD
TRI
0 0 0 1 1
RD
0 0 0
RD
0 0
P
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Chapter 5 XGATE (S12XGATEV2)
NOP
NOP
No Operation
Operation
No Operation for one cycle.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
NOP
Address
Mode
INH
Machine Code
0
0
0
0
0
0
0
1
0
0
Cycles
0
0
0
0
0
0
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 5 XGATE (S12XGATEV2)
OR
OR
Logical OR
Operation
RS1 | RS2 ⇒ RD
RD | IMM16⇒ RD (translates to ORL RD, #IMM16[7:0]; ORH RD, #IMM16[15:8]
Performs a bit wise logical OR between two 16 bit values and stores the result in the destination
register RD.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Refer to ORH instruction for #IMM16 operations.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
OR RD, RS1, RS2
OR RD, #IMM16
Address
Mode
Machine Code
RS1
Cycles
TRI
0
0
0
1
0
RD
RS2
1
0
P
IMM8
1
0
1
0
0
RD
IMM16[7:0]
P
IMM8
1
0
1
0
1
RD
IMM16[15:8]
P
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ORH
ORH
Logical OR Immediate 8 bit Constant
(High Byte)
Operation
RD.H | IMM8 ⇒ RD.H
Performs a bit wise logical OR between the high byte of register RD and an immediate 8 bit constant and
stores the result in the destination register RD.H. The low byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ORH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
1
0
1
RD
Cycles
IMM8
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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295
Chapter 5 XGATE (S12XGATEV2)
ORL
ORL
Logical OR Immediate 8 bit Constant
(Low Byte)
Operation
RD.L | IMM8 ⇒ RD.L
Performs a bit wise logical OR between the low byte of register RD and an immediate 8 bit constant and
stores the result in the destination register RD.L. The high byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 7 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ORL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
1
0
0
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
PAR
PAR
Calculate Parity
Operation
Calculates the number of ones in the register RD. The Carry flag will be set if the number is odd, otherwise
it will be cleared.
CCR Effects
N
Z
V
C
0
∆
0
∆
N:
Z:
V:
C:
0; cleared.
Set if RD is $0000; cleared otherwise.
0; cleared.
Set if there the number of ones in the register RD is odd; cleared otherwise.
Code and CPU Cycles
Source Form
PAR, RD
Address
Mode
MON
Machine Code
0
0
0
0
0
RD
1
1
Cycles
1
1
0
1
0
1
P
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Chapter 5 XGATE (S12XGATEV2)
ROL
ROL
Rotate Left
Operation
RD
n bits
n = RS or IMM4
Rotates the bits in register RD n positions to the left. The lower n bits of the register RD are filled with the
upper n bits. Two source forms are available. In the first form, the parameter n is contained in the
instruction code as an immediate operand. In the second form, the parameter is contained in the lower bits
of the source register RS[3:0]. All other bits in RS are ignored. If n is zero, no shift will take place and the
register RD will be unaffected; however, the condition code flags will be updated.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ROL RD, #IMM4
ROL RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
1
1
0
P
0
1
1
0
P
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Chapter 5 XGATE (S12XGATEV2)
ROR
ROR
Rotate Right
Operation
RD
n bits
n = RS or IMM4
Rotates the bits in register RD n positions to the right. The upper n bits of the register RD are filled with
the lower n bits. Two source forms are available. In the first form, the parameter n is contained in the
instruction code as an immediate operand. In the second form, the parameter is contained in the lower bits
of the source register RS[3:0]. All other bits in RS are ignored. If n is zero no shift will take place and the
register RD will be unaffected; however, the condition code flags will be updated.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
ROR RD, #IMM4
ROR RD, RS
Address
Mode
Machine Code
IMM4
0
0
0
0
1
RD
IMM4
DYA
0
0
0
0
1
RD
RS
Cycles
1
1
1
1
1
P
0
1
1
1
P
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299
Chapter 5 XGATE (S12XGATEV2)
RTS
RTS
Return to Scheduler
Operation
Terminates the current thread of program execution and remains idle until a new thread is started by the
hardware scheduler.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
RTS
Address
Mode
INH
Machine Code
0
0
0
0
0
0
1
0
0
0
Cycles
0
0
0
0
0
0
PA
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
SBC
SBC
Subtract with Carry
Operation
RS1 - RS2 - C ⇒ RD
Subtracts the content of register RS2 and the value of the Carry bit from the content of register RS1 using
binary subtraction and stores the result in the destination register RD. Also the zero flag is carried forward
from the previous operation allowing 32 and more bit subtractions.
Example:
SUB
SBC
BCC
R6,R4,R2
R7,R5,R3
; R7:R6 = R5:R4 - R3:R2
; conditional branch on 32 bit subtraction
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000 and Z was set before this operation; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & RD[15]new | RS1[15] & RS2[15] & RD[15]new
Set if there is a carry from bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & RD[15]new | RS2[15] & RD[15]new
Code and CPU Cycles
Source Form
SBC RD, RS1, RS2
Address
Mode
TRI
Machine Code
0
0
0
1
1
RD
RS1
Cycles
RS2
0
1
P
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Chapter 5 XGATE (S12XGATEV2)
SEX
SEX
Sign Extend Byte to Word
Operation
The result in RD is the 16 bit sign extended representation of the original two’s complement number in the
low byte of RD.L.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
SEX RD
Address
Mode
MON
Machine Code
0
0
0
0
0
RD
1
1
Cycles
1
1
0
1
0
0
P
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Chapter 5 XGATE (S12XGATEV2)
SIF
SIF
Set Interrupt Flag
Operation
Sets the Interrupt Flag of an XGATE Channel. This instruction supports two source forms. If inherent
address mode is used, then the interrupt flag of the current channel (XGCHID) will be set. If the monadic
address form is used, the interrupt flag associated with the channel id number contained in RS[6:0] is set.
The content of RS[15:7] is ignored.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
SIF
SIF RS
Address
Mode
Machine Code
INH
0
0
0
0
0
MON
0
0
0
0
0
0
1
1
RS
Cycles
0
0
0
0
0
0
0
0
PA
1
1
1
1
0
1
1
1
PA
MC9S12XHZ512 Data Sheet, Rev. 1.06
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303
Chapter 5 XGATE (S12XGATEV2)
SSEM
SSEM
Set Semaphore
Operation
Attempts to set a semaphore. The state of the semaphore will be stored in the Carry-Flag:
1 = Semaphore is locked by the RISC core
0 = Semaphore is locked by the S12X_CPU
In monadic address mode, bits RS[2:0] select the semaphore to be set.
CCR Effects
N
Z
V
C
—
—
—
∆
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Set if semaphore is locked by the RISC core; cleared otherwise.
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
Cycles
SSEM #IMM3
IMM3
0
0
0
0
0
IMM3
1
1
1
1
0
0
1
0
PA
SSEM RS
MON
0
0
0
0
0
RS
1
1
1
1
0
0
1
1
PA
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Chapter 5 XGATE (S12XGATEV2)
STB
STB
Store Byte to Memory
(Low Byte)
Operation
RS.L ⇒ M[RB, #OFFS5]
RS.L ⇒ M[RB, RI]
RS.L ⇒ M[RB, RI]; RI+1 ⇒ RI;
RI–1 ⇒ RI; RS.L ⇒ M[RB, RI]1
Stores the low byte of register RD to memory.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
STB RS, (RB, #OFFS5),
Address
Mode
Machine Code
Cycles
IDO5
0
1
0
1
0
RS
RB
OFFS5
Pw
STB RS, (RB, RI)
IDR
0
1
1
1
0
RS
RB
RI
0
0
Pw
STB RS, (RB, RI+)
IDR+
0
1
1
1
0
RS
RB
RI
0
1
Pw
STB RS, (RB, -RI)
-IDR
0
1
1
1
0
RS
RB
RI
1
0
Pw
1. If the same general purpose register is used as index (RI) and source register (RS), the unmodified content of the source
register is written to the memory: RS.L ⇒ M[RB, RS-1]; RS-1 ⇒ RS
MC9S12XHZ512 Data Sheet, Rev. 1.06
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305
Chapter 5 XGATE (S12XGATEV2)
STW
STW
Store Word to Memory
Operation
RS ⇒ M[RB, #OFFS5]
RS ⇒ M[RB, RI]
RS ⇒ M[RB, RI]; RI+2 ⇒ RI;
RI–2 ⇒ RI; RS ⇒ M[RB, RI]1
Stores the content of register RS to memory.
CCR Effects
N
Z
V
C
—
—
—
—
N:
Z:
V:
C:
Not affected.
Not affected.
Not affected.
Not affected.
Code and CPU Cycles
Source Form
STW RS, (RB, #OFFS5)
Address
Mode
Machine Code
Cycles
IDO5
0
1
0
1
1
RS
RB
OFFS5
PW
STW RS, (RB, RI)
IDR
0
1
1
1
1
RS
RB
RI
0
0
PW
STW RS, (RB, RI+)
IDR+
0
1
1
1
1
RS
RB
RI
0
1
PW
STW RS, (RB, -RI)
-IDR
0
1
1
1
1
RS
RB
RI
1
0
PW
1. If the same general purpose register is used as index (RI) and source register (RS), the unmodified content of the source
register is written to the memory: RS ⇒ M[RB, RS–2]; RS–2 ⇒ RS
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 5 XGATE (S12XGATEV2)
SUB
SUB
Subtract without Carry
Operation
RS1 – RS2
⇒ RD
RD − IMM16 ⇒ RD (translates to SUBL RD, #IMM16[7:0]; SUBH RD, #IMM16{15:8])
Subtracts two 16 bit values and stores the result in the destination register RD.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS1[15] & RS2[15] & RD[15]new | RS1[15] & RS2[15] & RD[15]new
Refer to SUBH instruction for #IMM16 operations.
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RS1[15] & RS2[15] | RS1[15] & RD[15]new | RS2[15] & RD[15]new
Refer to SUBH instruction for #IMM16 operations.
Code and CPU Cycles
Source Form
SUB RD, RS1, RS2
SUB RD, #IMM16
Address
Mode
Machine Code
RS1
Cycles
TRI
0
0
0
1
1
RD
RS2
0
0
P
IMM8
1
1
0
0
0
RD
IMM16[7:0]
P
IMM8
1
1
0
0
1
RD
IMM16[15:8]
P
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307
Chapter 5 XGATE (S12XGATEV2)
SUBH
SUBH
Subtract Immediate 8 bit Constant
(High Byte)
Operation
RD – IMM8:$00 ⇒ RD
Subtracts a signed immediate 8 bit constant from the content of high byte of register RD and using binary
subtraction and stores the result in the high byte of destination register RD. This instruction can be used
after an SUBL for a 16 bit immediate subtraction.
Example:
SUBL
SUBH
R2,#LOWBYTE
R2,#HIGHBYTE
; R2 = R2 - 16 bit immediate
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RD[15]old & IMM8[7] & RD[15]new | RD[15]old & IMM8[7] & RD[15]new
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RD[15]old & IMM8[7] | RD[15]old & RD[15]new | IMM8[7] & RD[15]new
Code and CPU Cycles
Source Form
SUBH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
0
0
1
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
SUBL
Subtract Immediate 8 bit Constant
(Low Byte)
SUBL
Operation
RD – $00:IMM8 ⇒ RD
Subtracts an immediate 8 bit constant from the content of register RD using binary subtraction and stores
the result in the destination register RD.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the 8 bit operation; cleared otherwise.
RD[15]old & RD[15]new
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RD[15]old & RD[15]new
Code and CPU Cycles
Source Form
SUBL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
1
0
0
0
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
TFR
TFR
Transfer from and to Special Registers
Operation
TFR RD,CCR: CCR ⇒ RD[3:0]; 0 ⇒ RD[15:4]
TFR CCR,RD: RD[3:0] ⇒ CCR
TFR RD,PC:
PC+4 ⇒ RD
Transfers the content of one RISC core register to another.
The TFR RD,PC instruction can be used to implement relative subroutine calls.
Example:
RETADDR
SUBR
TFR
BRA
...
...
JAL
R7,PC
SUBR
;Return address (RETADDR) is stored in R7
;Relative branch to subroutine (SUBR)
R7
;Jump to return address (RETADDR)
CCR Effects
TFR RD,CCR, TFR RD,PC:
TFR CCR,RS:
N
Z
V
C
N
Z
V
C
—
—
—
—
∆
∆
∆
∆
Not affected.
Not affected.
Not affected.
Not affected.
N:
Z:
V:
C:
N:
Z:
V:
C:
RS[3].
RS[2].
RS[1].
RS[0].
Code and CPU Cycles
Source Form
Address
Mode
Machine Code
Cycles
TFR RD,CCR CCR ⇒ RD
MON
0
0
0
0
0
RD
1
1
1
1
1
0
0
0
P
TFR CCR,RS RS ⇒ CCR
MON
0
0
0
0
0
RS
1
1
1
1
1
0
0
1
P
TFR RD,PCPC+4 ⇒ RD
MON
0
0
0
0
0
RD
1
1
1
1
1
0
1
0
P
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Chapter 5 XGATE (S12XGATEV2)
TST
TST
Test Register
Operation
RS – 0 ⇒ NONE (translates to SUB R0, RS, R0)
Subtracts zero from the content of register RS using binary subtraction and discards the result.
CCR Effects
N
Z
V
C
∆
∆
∆
∆
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Set if a two´s complement overflow resulted from the operation; cleared otherwise.
RS[15] & result[15]
Set if there is a carry from the bit 15 of the result; cleared otherwise.
RS1[15] & result[15]
Code and CPU Cycles
Source Form
TST RS
Address
Mode
TRI
Machine Code
0
0
0
1
1
0
0
0
RS1
Cycles
0
0
0
0
0
P
MC9S12XHZ512 Data Sheet, Rev. 1.06
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311
Chapter 5 XGATE (S12XGATEV2)
XNOR
XNOR
Logical Exclusive NOR
Operation
~(RS1 ^ RS2) ⇒ RD
~(RD ^ IMM16)⇒ RD
(translates to XNOR RD, #IMM16{15:8]; XNOR RD, #IMM16[7:0])
Performs a bit wise logical exclusive NOR between two 16 bit values and stores the result in the destination
register RD.
Remark: Using R0 as a source registers will calculate the one’s complement of the other source register.
Using R0 as both source operands will fill RD with $FFFF.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the result is $0000; cleared otherwise.
Refer to XNORH instruction for #IMM16 operations.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
XNOR RD, RS1, RS2
XNOR RD, #IMM16
Address
Mode
Machine Code
RS1
Cycles
TRI
0
0
0
1
0
RD
RS2
1
1
P
IMM8
1
0
1
1
0
RD
IMM16[7:0]
P
IMM8
1
0
1
1
1
RD
IMM16[15:8]
P
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Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
XNORH
Logical Exclusive NOR Immediate
8 bit Constant (High Byte)
XNORH
Operation
~(RD.H ^ IMM8) ⇒ RD.H
Performs a bit wise logical exclusive NOR between the high byte of register RD and an immediate 8 bit
constant and stores the result in the destination register RD.H. The low byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 15 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
XNORH RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
1
1
1
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
XNORL
Logical Exclusive NOR Immediate
8 bit Constant (Low Byte)
XNORL
Operation
~(RD.L ^ IMM8) ⇒ RD.L
Performs a bit wise logical exclusive NOR between the low byte of register RD and an immediate 8 bit
constant and stores the result in the destination register RD.L. The high byte of RD is not affected.
CCR Effects
N
Z
V
C
∆
∆
0
—
N:
Z:
V:
C:
Set if bit 7 of the result is set; cleared otherwise.
Set if the 8 bit result is $00; cleared otherwise.
0; cleared.
Not affected.
Code and CPU Cycles
Source Form
XNORL RD, #IMM8
Address
Mode
IMM8
Machine Code
1
0
1
1
0
RD
Cycles
IMM8
P
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Chapter 5 XGATE (S12XGATEV2)
5.8.6
Instruction Coding
Table 5-17 summarizes all XGATE instructions in the order of their machine coding.
Table 5-17. Instruction Set Summary (Sheet 1 of 3)
Functionality
Return to Scheduler and Others
BRK
NOP
RTS
SIF
Semaphore Instructions
CSEM IMM3
CSEM RS
SSEM IMM3
SSEM RS
Single Register Instructions
SEX RD
PAR RD
JAL RD
SIF RS
Special Move instructions
TFR RD,CCR
TFR CCR,RS
TFR RD,PC
Shift instructions Dyadic
BFFO RD, RS
ASR RD, RS
CSL RD, RS
CSR RD, RS
LSL RD, RS
LSR RD, RS
ROL RD, RS
ROR RD, RS
Shift instructions immediate
ASR RD, #IMM4
CSL RD, #IMM4
CSR RD, #IMM4
LSL RD, #IMM4
LSR RD, #IMM4
ROL RD, #IMM4
ROR RD, #IMM4
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
IMM3
RS
IMM3
RS
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RD
RD
RD
RS
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RD
RS
RD
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
RD
RD
RD
RD
RD
RD
RD
RD
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
RD
RD
RD
RD
RD
RD
RD
1
1
1
1
1
1
1
0
0
0
1
1
1
1
0
1
1
0
0
1
1
1
0
1
0
1
0
1
RS
RS
RS
RS
RS
RS
RS
RS
IMM4
IMM4
IMM4
IMM4
IMM4
IMM4
IMM4
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
315
Chapter 5 XGATE (S12XGATEV2)
Table 5-17. Instruction Set Summary (Sheet 2 of 3)
Functionality
Logical Triadic
AND RD, RS1, RS2
OR RD, RS1, RS2
XNOR RD, RS1, RS2
Arithmetic Triadic
SUB RD, RS1, RS2
SBC RD, RS1, RS2
ADD RD, RS1, RS2
ADC RD, RS1, RS2
Branches
BCC REL9
BCS REL9
BNE REL9
BEQ REL9
BPL REL9
BMI REL9
BVC REL9
BVS REL9
BHI REL9
BLS REL9
BGE REL9
BLT REL9
BGT REL9
BLE REL9
BRA REL10
Load and Store Instructions
LDB RD, (RB, #OFFS5)
LDW RD, (RB, #OFFS5)
STB RS, (RB, #OFFS5)
STW RS, (RB, #OFFS5)
LDB RD, (RB, RI)
LDW RD, (RB, RI)
STB RS, (RB, RI)
STW RS, (RB, RI)
LDB RD, (RB, RI+)
LDW RD, (RB, RI+)
STB RS, (RB, RI+)
STW RS, (RB, RI+)
LDB RD, (RB, –RI)
LDW RD, (RB, –RI)
STB RS, (RB, –RI)
STW RS, (RB, –RI)
Bit Field Instructions
BFEXT RD, RS1, RS2
BFINS RD, RS1, RS2
BFINSI RD, RS1, RS2
BFINSX RD, RS1, RS2
Logic Immediate Instructions
ANDL RD, #IMM8
15
14
13
12
11
10
9
8
7
6
0
0
0
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
RD
RD
RS
RS
RD
RD
RS
RS
RD
RD
RS
RS
RD
RD
RS
RS
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
RB
0
0
0
0
1
1
1
1
1
1
1
1
0
0
1
1
0
1
0
1
RD
RD
RD
RD
RS1
RS1
RS1
RS1
1
0
0
0
0
RD
5
4
3
2
1
0
0
1
1
0
0
1
0
0
1
1
0
1
0
1
RI
RI
RI
RI
RI
RI
RI
RI
RI
RI
RI
RI
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
RS2
RS2
RS2
RS2
1
1
1
1
1
1
1
1
RD
RS1
RS2
RD
RS1
RS2
RD
RS1
RS2
For compare use SUB R0,Rs1,Rs2
RD
RS1
RS2
RD
RS1
RS2
RD
RS1
RS2
RD
RS1
RS2
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL9
REL10
OFFS5
OFFS5
OFFS5
OFFS5
IMM8
MC9S12XHZ512 Data Sheet, Rev. 1.06
316
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
Table 5-17. Instruction Set Summary (Sheet 3 of 3)
Functionality
ANDH RD, #IMM8
BITL RD, #IMM8
BITH RD, #IMM8
ORL RD, #IMM8
ORH RD, #IMM8
XNORL RD, #IMM8
XNORH RD, #IMM8
Arithmetic Immediate Instructions
SUBL RD, #IMM8
SUBH RD, #IMM8
CMPL RS, #IMM8
CPCH RS, #IMM8
ADDL RD, #IMM8
ADDH RD, #IMM8
LDL RD, #IMM8
LDH RD, #IMM8
15
14
13
12
11
10
9
8
7
6
5
4
3
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
1
1
0
0
1
1
1
0
1
0
1
0
1
RD
RD
RD
RD
RD
RD
RD
IMM8
IMM8
IMM8
IMM8
IMM8
IMM8
IMM8
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
RD
RD
RS
RS
RD
RD
RD
RD
IMM8
IMM8
IMM8
IMM8
IMM8
IMM8
IMM8
IMM8
2
1
0
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
317
Chapter 5 XGATE (S12XGATEV2)
5.9
Initialization and Application Information
5.9.1
Initialization
The recommended initialization of the XGATE is as follows:
1. Clear the XGE bit to suppress any incoming service requests.
2. Make sure that no thread is running on the XGATE. This can be done in several ways:
a) Poll the XGCHID register until it reads $00. Also poll XGDBG and XGSWEIF to make sure
that the XGATE has not been stopped.
b) Enter Debug Mode by setting the XGDBG bit. Clear the XGCHID register. Clear the XGDBG
bit.
The recommended method is a).
3. Set the XGVBR register to the lowest address of the XGATE vector space.
4. Clear all Channel ID flags.
5. Copy XGATE vectors and code into the RAM.
6. Initialize the S12X_INT module.
7. Enable the XGATE by setting the XGE bit.
The following code example implements the XGATE initialization sequence.
5.9.2
Code Example (Transmit "Hello World!" on SCI)
SCI_REGS
SCIBDH
SCIBDL
SCICR2
SCISR1
SCIDRL
TIE
TE
RE
SCI_VEC
CPU S12X
;###########################################
;#
SYMBOLS
#
;###########################################
EQU $00C8
;SCI register space
EQU SCI_REGS+$00
;SCI Baud Rate Register
EQU SCI_REGS+$00
;SCI Baud Rate Register
EQU SCI_REGS+$03
;SCI Control Register 2
EQU SCI_REGS+$04
;SCI Status Register 1
EQU SCI_REGS+$07
;SCI Control Register 2
EQU $80
;TIE bit mask
EQU $08
;TE bit mask
EQU $04
;RE bit mask
EQU $D6
;SCI vector number
INT_REGS
INT_CFADDR
INT_CFDATA
RQST
EQU
EQU
EQU
EQU
INT_REGS+$07
INT_REGS+$08
$80
$0120
;S12X_INT register space
;Interrupt Configuration Address Register
;Interrupt Configuration Data Registers
;RQST bit mask
XGATE_REGS
XGMCTL
XGMCTL_CLEAR
XGMCTL_ENABLE
XGCHID
XGVBR
XGIF
EQU
EQU
EQU
EQU
EQU
EQU
EQU
$0380
XGATE_REGS+$00
$FA02
$8282
XGATE_REGS+$02
XGATE_REGS+$06
XGATE_REGS+$08
;XGATE register space
;XGATE Module Control Register
;Clear all XGMCTL bits
;Enable XGATE
;XGATE Channel ID Register
;XGATE ISP Select Register
;XGATE Interrupt Flag Vector
MC9S12XHZ512 Data Sheet, Rev. 1.06
318
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
XGSWT
XGSEM
EQU
EQU
XGATE_REGS+$18
XGATE_REGS+$1A
;XGATE Software Trigger Register
;XGATE Semaphore Register
RPAGE
EQU
$0016
RAM_SIZE
EQU
32*$400
RAM_START
RAM_START_XG
RAM_START_GLOB
EQU
EQU
EQU
$1000
$10000-RAM_SIZE
$100000-RAM_SIZE
XGATE_VECTORS
XGATE_VECTORS_XG
EQU
EQU
RAM_START
RAM_START_XG
XGATE_DATA
XGATE_DATA_XG
EQU
EQU
RAM_START+(4*128)
RAM_START_XG+(4*128)
XGATE_CODE
XGATE_CODE_XG
EQU
EQU
XGATE_DATA+(XGATE_CODE_FLASH-XGATE_DATA_FLASH)
XGATE_DATA_XG+(XGATE_CODE_FLASH-XGATE_DATA_FLASH)
BUS_FREQ_HZ
EQU
40000000
;32k RAM
;###########################################
;#
S12XE VECTOR TABLE
#
;###########################################
ORG $FF10 ;non-maskable interrupts
DW
DUMMY_ISR DUMMY_ISR DUMMY_ISR DUMMY_ISR
ORG
DW
$FFF4 ;non-maskable interrupts
DUMMY_ISR DUMMY_ISR DUMMY_ISR
;###########################################
;#
DISABLE COP
#
;###########################################
ORG $FF0E
DW
$FFFE
ORG
$C000
START_OF_CODE
;###########################################
;#
INITIALIZE S12XE CORE
#
;###########################################
SEI
MOVB #(RAM_START_GLOB>>12), RPAGE;set RAM page
INIT_SCI
INIT_INT
;###########################################
;#
INITIALIZE SCI
#
;###########################################
MOVW #(BUS_FREQ_HZ/(16*9600)), SCIBDH;set baud rate
MOVB #(TIE|TE), SCICR2;enable tx buffer empty interrupt
;###########################################
;#
INITIALIZE S12X_INT
#
;###########################################
MOVB #(SCI_VEC&$F0), INT_CFADDR ;switch SCI interrupts to XGATE
MOVB #RQST|$01, INT_CFDATA+((SCI_VEC&$0F)>>1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
319
Chapter 5 XGATE (S12XGATEV2)
INIT_XGATE
INIT_XGATE_BUSY_LOOP
;###########################################
;#
INITIALIZE XGATE
#
;###########################################
MOVW #XGMCTL_CLEAR , XGMCTL;clear all XGMCTL bits
TST
BNE
XGCHID
;wait until current thread is finished
INIT_XGATE_BUSY_LOOP
LDX
LDD
STD
STD
STD
STD
STD
STD
STD
STD
#XGIF
#$FFFF
2,X+
2,X+
2,X+
2,X+
2,X+
2,X+
2,X+
2,X+
;clear all channel interrupt flags
MOVW #XGATE_VECTORS_XG, XGVBR;set vector base register
MOVW #$FF00, XGSWT
INIT_XGATE_VECTAB_LOOP
;clear all software triggers
;###########################################
;#
INITIALIZE XGATE VECTOR TABLE
#
;###########################################
LDAA #128
;build XGATE vector table
LDY #XGATE_VECTORS
MOVW #XGATE_DUMMY_ISR_XG, 4,Y+
DBNE A, INIT_XGATE_VECTAB_LOOP
MOVW #XGATE_CODE_XG, RAM_START+(2*SCI_VEC)
MOVW #XGATE_DATA_XG, RAM_START+(2*SCI_VEC)+2
COPY_XGATE_CODE
COPY_XGATE_CODE_LOOP
START_XGATE
DUMMY_ISR
;###########################################
;#
COPY XGATE CODE
#
;###########################################
LDX #XGATE_DATA_FLASH
MOVW 2,X+, 2,Y+
MOVW 2,X+, 2,Y+
MOVW 2,X+, 2,Y+
MOVW 2,X+, 2,Y+
CPX #XGATE_CODE_FLASH_END
BLS COPY_XGATE_CODE_LOOP
;###########################################
;#
START XGATE
#
;###########################################
MOVW #XGMCTL_ENABLE, XGMCTL;enable XGATE
BRA *
;###########################################
;#
DUMMY INTERRUPT SERVICE ROUTINE
#
;###########################################
RTI
CPU
XGATE
MC9S12XHZ512 Data Sheet, Rev. 1.06
320
Freescale Semiconductor
Chapter 5 XGATE (S12XGATEV2)
XGATE_DATA_FLASH
XGATE_DATA_SCI
XGATE_DATA_IDX
XGATE_DATA_MSG
XGATE_CODE_FLASH
XGATE_CODE_DONE
XGATE_CODE_FLASH_END
XGATE_DUMMY_ISR_XG
;###########################################
;#
XGATE DATA
#
;###########################################
ALIGN 1
EQU *
EQU *-XGATE_DATA_FLASH
DW
SCI_REGS
;pointer to SCI register space
EQU *-XGATE_DATA_FLASH
DB
XGATE_DATA_MSG ;string pointer
EQU *-XGATE_DATA_FLASH
FCC "Hello World!
;ASCII string
DB
$0D
;CR
;###########################################
;#
XGATE CODE
#
;###########################################
ALIGN 1
LDW R2,(R1,#XGATE_DATA_SCI);SCI -> R2
LDB R3,(R1,#XGATE_DATA_IDX);msg -> R3
LDB R4,(R1,R3+)
;curr. char -> R4
STB R3,(R1,#XGATE_DATA_IDX);R3 -> idx
LDB R0,(R2,#(SCISR1-SCI_REGS));initiate SCI transmit
STB R4,(R2,#(SCIDRL-SCI_REGS));initiate SCI transmit
CMPL R4,#$0D
BEQ XGATE_CODE_DONE
RTS
LDL R4,#$00
;disable SCI interrupts
STB R4,(R2,#(SCICR2-SCI_REGS))
LDL R3,#XGATE_DATA_MSG;reset R3
STB R3,(R1,#XGATE_DATA_IDX)
RTS
EQU (XGATE_CODE_FLASH_END-XGATE_CODE_FLASH)+XGATE_CODE_XG
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
321
Chapter 5 XGATE (S12XGATEV2)
MC9S12XHZ512 Data Sheet, Rev. 1.06
322
Freescale Semiconductor
Chapter 6
Security (S12X9SECV2)
Table 6-1. Revision History
Revision
Number
Revision
Date
02.00
27 Aug 2004
reviewed and updated for S12XD architecture
02.01
21 Feb 2007
added S12XE, S12XF and S12XS architectures
02.02
19 Apr 2007
corrected statement about Backdoor key access via BDM on XE, XF, XS
6.1
Sections
Affected
Description of Changes
Introduction
This specification describes the function of the security mechanism in the S12XD chip family (9SEC).
NOTE
No security feature is absolutely secure. However, Freescale’s strategy is to
make reading or copying the FLASH and/or EEPROM difficult for
unauthorized users.
6.1.1
Features
The user must be reminded that part of the security must lie with the application code. An extreme example
would be application code that dumps the contents of the internal memory. This would defeat the purpose
of security. At the same time, the user may also wish to put a backdoor in the application program. An
example of this is the user downloads a security key through the SCI, which allows access to a
programming routine that updates parameters stored in another section of the Flash memory.
The security features of the S12X chip family (in secure mode) are:
• Protect the content of non-volatile memories (Flash, EEPROM)
• Execution of NVM commands is restricted
• Disable access to internal memory via background debug module (BDM)
• Disable access to internal Flash/EEPROM in expanded modes
• Disable debugging features for the CPU and XGATE
6.1.2
Modes of Operation
Table 6-2 gives an overview over availability of security relevant features in unsecure and secure modes.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
323
Chapter 6 Security (S12X9SECV2)
Table 6-2. Feature Availability in Unsecure and Secure Modes on S12XD
Unsecure Mode
Secure Mode
NS
SS
NX
ES
EX
ST
NS
SS
NX
ES
EX
ST
Flash Array Access
✔
✔
✔(1)
✔1
✔1
✔1
✔
✔
—
—
—
—
EEPROM Array Access
✔
✔
✔
✔
✔
✔
✔
✔
—
—
—
—
NVM Commands
✔(2)
✔
✔2
✔2
✔2
✔
✔2
✔2
✔2
✔2
✔2
✔2
BDM
✔
✔
✔
✔
✔
✔
—
✔(3)
—
—
—
—
DBG Module Trace
✔
✔
✔
✔
✔
✔
—
—
—
—
—
—
XGATE Debugging
✔
✔
✔
✔
✔
✔
—
—
—
—
—
—
External Bus Interface
—
—
✔
✔
✔
✔
—
—
✔
✔
✔
✔
Internal status visible
multiplexed on
external bus
—
—
—
✔
✔
—
—
—
—
✔
✔
—
Internal accesses visible
—
—
—
—
—
✔
—
—
—
—
—
✔
on external bus
1. Availability of Flash arrays in the memory map depends on ROMCTL/EROMCTL pins and/or the state of the
ROMON/EROMON bits in the MMCCTL1 register. Please refer to the S12X_MMC block guide for detailed
information.
2. Restricted NVM command set only. Please refer to the NVM wrapper block guides for detailed information.
3. BDM hardware commands restricted to peripheral registers only.
6.1.3
Securing the Microcontroller
Once the user has programmed the Flash and EEPROM, the chip can be secured by programming the
security bits located in the options/security byte in the Flash memory array. These non-volatile bits will
keep the device secured through reset and power-down.
The options/security byte is located at address 0xFF0F (= global address 0x7F_FF0F) in the Flash memory
array. This byte can be erased and programmed like any other Flash location. Two bits of this byte are used
for security (SEC[1:0]). On devices which have a memory page window, the Flash options/security byte
is also available at address 0xBF0F by selecting page 0x3F with the PPAGE register. The contents of this
byte are copied into the Flash security register (FSEC) during a reset sequence.
0xFF0F
7
6
5
4
3
2
1
0
KEYEN1
KEYEN0
NV5
NV4
NV3
NV2
SEC1
SEC0
Figure 6-1. Flash Options/Security Byte
The meaning of the bits KEYEN[1:0] is shown in Table 6-3. Please refer to Section 6.1.5.1, “Unsecuring
the MCU Using the Backdoor Key Access” for more information.
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Table 6-3. Backdoor Key Access Enable Bits
KEYEN[1:0]
Backdoor Key
Access Enabled
00
0 (disabled)
01
0 (disabled)
10
1 (enabled)
11
0 (disabled)
The meaning of the security bits SEC[1:0] is shown in Table 6-4. For security reasons, the state of device
security is controlled by two bits. To put the device in unsecured mode, these bits must be programmed to
SEC[1:0] = ‘10’. All other combinations put the device in a secured mode. The recommended value to put
the device in secured state is the inverse of the unsecured state, i.e. SEC[1:0] = ‘01’.
Table 6-4. Security Bits
SEC[1:0]
Security State
00
1 (secured)
01
1 (secured)
10
0 (unsecured)
11
1 (secured)
NOTE
Please refer to the Flash block guide for actual security configuration (in
section “Flash Module Security”).
6.1.4
Operation of the Secured Microcontroller
By securing the device, unauthorized access to the EEPROM and Flash memory contents can be prevented.
However, it must be understood that the security of the EEPROM and Flash memory contents also depends
on the design of the application program. For example, if the application has the capability of downloading
code through a serial port and then executing that code (e.g. an application containing bootloader code),
then this capability could potentially be used to read the EEPROM and Flash memory contents even when
the microcontroller is in the secure state. In this example, the security of the application could be enhanced
by requiring a challenge/response authentication before any code can be downloaded.
Secured operation has the following effects on the microcontroller:
6.1.4.1
•
•
•
•
Normal Single Chip Mode (NS)
Background debug module (BDM) operation is completely disabled.
Execution of Flash and EEPROM commands is restricted. Please refer to the NVM block guide for
details.
Tracing code execution using the DBG module is disabled.
Debugging XGATE code (breakpoints, single-stepping) is disabled.
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6.1.4.2
•
•
•
•
•
Special Single Chip Mode (SS)
BDM firmware commands are disabled.
BDM hardware commands are restricted to the register space.
Execution of Flash and EEPROM commands is restricted. Please refer to the NVM block guide for
details.
Tracing code execution using the DBG module is disabled.
Debugging XGATE code (breakpoints, single-stepping) is disabled.
Special single chip mode means BDM is active after reset. The availability of BDM firmware commands
depends on the security state of the device. The BDM secure firmware first performs a blank check of both
the Flash memory and the EEPROM. If the blank check succeeds, security will be temporarily turned off
and the state of the security bits in the appropriate Flash memory location can be changed If the blank
check fails, security will remain active, only the BDM hardware commands will be enabled, and the
accessible memory space is restricted to the peripheral register area. This will allow the BDM to be used
to erase the EEPROM and Flash memory without giving access to their contents. After erasing both Flash
memory and EEPROM, another reset into special single chip mode will cause the blank check to succeed
and the options/security byte can be programmed to “unsecured” state via BDM.
While the BDM is executing the blank check, the BDM interface is completely blocked, which means that
all BDM commands are temporarily blocked.
6.1.4.3
•
•
•
•
•
Expanded Modes (NX, ES, EX, and ST)
BDM operation is completely disabled.
Internal Flash memory and EEPROM are disabled.
Execution of Flash and EEPROM commands is restricted. Please refer to the NVM block guide for
details.
Tracing code execution using the DBG module is disabled.
Debugging XGATE code (breakpoints, single-stepping) is disabled
6.1.5
Unsecuring the Microcontroller
Unsecuring the microcontroller can be done by three different methods:
1. Backdoor key access
2. Reprogramming the security bits
3. Complete memory erase (special modes)
6.1.5.1
Unsecuring the MCU Using the Backdoor Key Access
In normal modes (single chip and expanded), security can be temporarily disabled using the backdoor key
access method. This method requires that:
• The backdoor key at 0xFF00–0xFF07 (= global addresses 0x7F_FF00–0x7F_FF07) has been
programmed to a valid value.
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•
•
The KEYEN[1:0] bits within the Flash options/security byte select ‘enabled’.
In single chip mode, the application program programmed into the microcontroller must be
designed to have the capability to write to the backdoor key locations.
The backdoor key values themselves would not normally be stored within the application data, which
means the application program would have to be designed to receive the backdoor key values from an
external source (e.g. through a serial port). It is not possible to download the backdoor keys using
background debug mode.
The backdoor key access method allows debugging of a secured microcontroller without having to erase
the Flash. This is particularly useful for failure analysis.
NOTE
No word of the backdoor key is allowed to have the value 0x0000 or
0xFFFF.
6.1.5.2
Backdoor Key Access Sequence
These are the necessary steps for a successful backdoor key access sequence:
1. Set the KEYACC bit in the Flash configuration register FCNFG.
2. Write the first 16-bit word of the backdoor key to 0xFF00 (0x7F_FF00).
3. Write the second 16-bit word of the backdoor key to 0xFF02 (0x7F_FF02).
4. Write the third 16-bit word of the backdoor key to 0xFF04 (0x7F_FF04).
5. Write the fourth 16-bit word of the backdoor key to 0xFF06 (0x7F_FF06).
6. Clear the KEYACC bit in the Flash Configuration register FCNFG.
NOTE
Flash cannot be read while KEYACC is set. Therefore the code for the
backdoor key access sequence must execute from RAM.
If all four 16-bit words match the Flash contents at 0xFF00–0xFF07 (0x7F_FF00–0x7F_FF07), the
microcontroller will be unsecured and the security bits SEC[1:0] in the Flash Security register FSEC will
be forced to the unsecured state (‘10’). The contents of the Flash options/security byte are not changed by
this procedure, and so the microcontroller will revert to the secure state after the next reset unless further
action is taken as detailed below.
If any of the four 16-bit words does not match the Flash contents at 0xFF00–0xFF07
(0x7F_FF00–0x7F_FF07), the microcontroller will remain secured.
6.1.6
Reprogramming the Security Bits
In normal single chip mode (NS), security can also be disabled by erasing and reprogramming the security
bits within Flash options/security byte to the unsecured value. Because the erase operation will erase the
entire sector from 0xFE00–0xFFFF (0x7F_FE00–0x7F_FFFF), the backdoor key and the interrupt vectors
will also be erased; this method is not recommended for normal single chip mode. The application
software can only erase and program the Flash options/security byte if the Flash sector containing the Flash
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options/security byte is not protected (see Flash protection). Thus Flash protection is a useful means of
preventing this method. The microcontroller will enter the unsecured state after the next reset following
the programming of the security bits to the unsecured value.
This method requires that:
• The application software previously programmed into the microcontroller has been designed to
have the capability to erase and program the Flash options/security byte, or security is first disabled
using the backdoor key method, allowing BDM to be used to issue commands to erase and program
the Flash options/security byte.
• The Flash sector containing the Flash options/security byte is not protected.
6.1.7
Complete Memory Erase (Special Modes)
The microcontroller can be unsecured in special modes by erasing the entire EEPROM and Flash memory
contents.
When a secure microcontroller is reset into special single chip mode (SS), the BDM firmware verifies
whether the EEPROM and Flash memory are erased. If any EEPROM or Flash memory address is not
erased, only BDM hardware commands are enabled. BDM hardware commands can then be used to write
to the EEPROM and Flash registers to mass erase the EEPROM and all Flash memory blocks.
When next reset into special single chip mode, the BDM firmware will again verify whether all EEPROM
and Flash memory are erased, and this being the case, will enable all BDM commands, allowing the Flash
options/security byte to be programmed to the unsecured value. The security bits SEC[1:0] in the Flash
security register will indicate the unsecure state following the next reset.
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Special single chip erase and unsecure sequence:
1. Reset into special single chip mode.
2. Write an appropriate value to the ECLKDIV register for correct timing.
3. Write 0xFF to the EPROT register to disable protection.
4. Write 0x30 to the ESTAT register to clear the PVIOL and ACCERR bits.
5. Write 0x0000 to the EDATA register (0x011A–0x011B).
6. Write 0x0000 to the EADDR register (0x0118–0x0119).
7. Write 0x41 (mass erase) to the ECMD register.
8. Write 0x80 to the ESTAT register to clear CBEIF.
9. Write an appropriate value to the FCLKDIV register for correct timing.
10. Write 0x00 to the FCNFG register to select Flash block 0.
11. Write 0x10 to the FTSTMOD register (0x0102) to set the WRALL bit, so the following writes
affect all Flash blocks.
12. Write 0xFF to the FPROT register to disable protection.
13. Write 0x30 to the FSTAT register to clear the PVIOL and ACCERR bits.
14. Write 0x0000 to the FDATA register (0x010A–0x010B).
15. Write 0x0000 to the FADDR register (0x0108–0x0109).
16. Write 0x41 (mass erase) to the FCMD register.
17. Write 0x80 to the FSTAT register to clear CBEIF.
18. Wait until all CCIF flags are set.
19. Reset back into special single chip mode.
20. Write an appropriate value to the FCLKDIV register for correct timing.
21. Write 0x00 to the FCNFG register to select Flash block 0.
22. Write 0xFF to the FPROT register to disable protection.
23. Write 0xFFBE to Flash address 0xFF0E.
24. Write 0x20 (program) to the FCMD register.
25. Write 0x80 to the FSTAT register to clear CBEIF.
26. Wait until the CCIF flag in FSTAT is are set.
27. Reset into any mode.
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Chapter 7
Clocks and Reset Generator (S12CRGV6)
7.1
Introduction
This specification describes the function of the clocks and reset generator (CRG).
7.1.1
Features
The main features of this block are:
• Phase locked loop (PLL) frequency multiplier
— Reference divider
— Automatic bandwidth control mode for low-jitter operation
— Automatic frequency lock detector
— Interrupt request on entry or exit from locked condition
— Self clock mode in absence of reference clock
• System clock generator
— Clock quality check
— User selectable fast wake-up from Stop in self-clock mode for power saving and immediate
program execution
— Clock switch for either oscillator or PLL based system clocks
• Computer operating properly (COP) watchdog timer with time-out clear window
• System reset generation from the following possible sources:
— Power on reset
— Low voltage reset
— Illegal address reset
— COP reset
— Loss of clock reset
— External pin reset
• Real-time interrupt (RTI)
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7.1.2
Modes of Operation
This subsection lists and briefly describes all operating modes supported by the CRG.
• Run mode
All functional parts of the CRG are running during normal run mode. If RTI or COP functionality
is required, the individual bits of the associated rate select registers (COPCTL, RTICTL) have to
be set to a nonzero value.
• Wait mode
In this mode, the PLL can be disabled automatically depending on the PLLSEL bit in the CLKSEL
register.
• Stop mode
Depending on the setting of the PSTP bit, stop mode can be differentiated between full stop mode
(PSTP = 0) and pseudo stop mode (PSTP = 1).
— Full stop mode
The oscillator is disabled and thus all system and core clocks are stopped. The COP and the
RTI remain frozen.
— Pseudo stop mode
The oscillator continues to run and most of the system and core clocks are stopped. If the
respective enable bits are set, the COP and RTI will continue to run, or else they remain frozen.
• Self clock mode
Self clock mode will be entered if the clock monitor enable bit (CME) and the self clock mode
enable bit (SCME) are both asserted and the clock monitor in the oscillator block detects a loss of
clock. As soon as self clock mode is entered, the CRG starts to perform a clock quality check. Self
clock mode remains active until the clock quality check indicates that the required quality of the
incoming clock signal is met (frequency and amplitude). Self clock mode should be used for safety
purposes only. It provides reduced functionality to the MCU in case a loss of clock is causing
severe system conditions.
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Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.1.3
Block Diagram
Figure 7-1 shows a block diagram of the CRG.
S12X_MMC
Voltage
Regulator
Illegal Address Reset
Power on Reset
Low Voltage Reset
CRG
RESET
CM fail
Clock
Monitor
OSCCLK
EXTAL
Oscillator
XTAL
COP Timeout
XCLKS
Reset
Generator
Clock Quality
Checker
COP
RTI
System Reset
Bus Clock
Core Clock
Oscillator Clock
Registers
XFC
VDDPLL
VSSPLL
PLLCLK
PLL
Clock and Reset
Control
Real Time Interrupt
PLL Lock Interrupt
Self Clock Mode
Interrupt
Figure 7-1. CRG Block Diagram
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7.2
External Signal Description
This section lists and describes the signals that connect off chip.
7.2.1
VDDPLL and VSSPLL — Operating and Ground Voltage Pins
These pins provide operating voltage (VDDPLL) and ground (VSSPLL) for the PLL circuitry. This allows
the supply voltage to the PLL to be independently bypassed. Even if PLL usage is not required, VDDPLL
and VSSPLL must be connected to properly.
7.2.2
XFC — External Loop Filter Pin
A passive external loop filter must be placed on the XFC pin. The filter is a second-order, low-pass filter
that eliminates the VCO input ripple. The value of the external filter network and the reference frequency
determines the speed of the corrections and the stability of the PLL. Refer to the device specification for
calculation of PLL Loop Filter (XFC) components. If PLL usage is not required, the XFC pin must be tied
to VDDPLL.
VDDPLL
CS
CP
MCU
RS
XFC
Figure 7-2. PLL Loop Filter Connections
7.2.3
RESET — Reset Pin
RESET is an active low bidirectional reset pin. As an input. it initializes the MCU asynchronously to a
known start-up state. As an open-drain output, it indicates that a system reset (internal to the MCU) has
been triggered.
7.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the CRG.
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7.3.1
Module Memory Map
Table 7-1 gives an overview on all CRG registers.
Table 7-1. CRG Memory Map
Address
Offset
Use
Access
0x_00
CRG Synthesizer Register (SYNR)
R/W
0x_01
CRG Reference Divider Register (REFDV)
R/W
1
0x_02
CRG Test Flags Register (CTFLG)
R/W
0x_03
CRG Flags Register (CRGFLG)
R/W
0x_04
CRG Interrupt Enable Register (CRGINT)
R/W
0x_05
CRG Clock Select Register (CLKSEL)
R/W
0x_06
CRG PLL Control Register (PLLCTL)
R/W
0x_07
CRG RTI Control Register (RTICTL)
R/W
0x_08
CRG COP Control Register (COPCTL)
R/W
0x_09
0x_0A
0x_0B
CRG Force and Bypass Test Register
CRG Test Control Register
(FORBYP)2
(CTCTL)3
CRG COP Arm/Timer Reset (ARMCOP)
R/W
R/W
R/W
1
CTFLG is intended for factory test purposes only.
FORBYP is intended for factory test purposes only.
3 CTCTL is intended for factory test purposes only.
2
NOTE
Register Address = Base Address + Address Offset, where the Base Address
is defined at the MCU level and the Address Offset is defined at the module
level.
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7.3.2
Register Descriptions
This section describes in address order all the CRG registers and their individual bits.
Register
Name
0x_00
SYNR
R
W
0x_02
CTFLG
W
0x_04
CRGINT
R
R
R
W
R
W
0x_05
CLKSEL
W
0x_06
PLLCTL
W
0x_07
RTICTL
R
4
3
2
1
Bit 0
0
0
SYN5
SYN4
SYN3
SYN2
SYN1
SYN0
0
0
REFDV5
REFDV4
REFDV3
REFDV2
REFDV1
REFDV0
0
0
0
0
0
0
0
0
RTIF
PORF
LVRF
LOCKIF
LOCK
TRACK
RTIE
ILAF
0
0
PLLSEL
PSTP
CME
0
LOCKIE
0
PLLON
AUTO
ACQ
FSTWKP
RTDEC
RTR6
RTR5
RTR4
RTR3
WCOP
RSBCK
0
0
0
0
0
0
0
1
0
0
R
0
0
W
Bit 7
Bit 6
R
R
W
W
0x_09
FORBYP
W
0x_0B
ARMCOP
5
0
0x_08
COPCTL
0x_0A
CTCTL
6
W
0x_01
REFDV
0x_03
CRGFLG
Bit 7
R
R
R
PLLWAI
0
SCMIF
SCMIE
SCM
0
RTIWAI
COPWAI
PRE
PCE
SCME
RTR2
RTR1
RTR0
CR2
CR1
CR0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
WRTMASK
W
= Unimplemented or Reserved
Figure 7-3. S12CRGV6 Register Summary
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7.3.2.1
CRG Synthesizer Register (SYNR)
The SYNR register controls the multiplication factor of the PLL. If the PLL is on, the count in the loop
divider (SYNR) register effectively multiplies up the PLL clock (PLLCLK) from the reference frequency
by 2 x (SYNR + 1). PLLCLK will not be below the minimum VCO frequency (fSCM).
( SYNR + 1 )
PLLCLK = 2xOSCCLKx -----------------------------------( REFDV + 1 )
NOTE
If PLL is selected (PLLSEL=1), Bus Clock = PLLCLK / 2
Bus Clock must not exceed the maximum operating system frequency.
Module Base +0x_00
R
7
6
0
0
0
0
W
Reset
5
4
3
2
1
0
SYN5
SYN4
SYN3
SYN2
SYN1
SYN0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-4. CRG Synthesizer Register (SYNR)
Read: Anytime
Write: Anytime except if PLLSEL = 1
NOTE
Write to this register initializes the lock detector bit and the track detector
bit.
7.3.2.2
CRG Reference Divider Register (REFDV)
The REFDV register provides a finer granularity for the PLL multiplier steps. The count in the reference
divider divides OSCCLK frequency by REFDV + 1.
Module Base +0x_01
R
7
6
0
0
W
Reset
0
0
5
4
3
2
1
0
REFDV5
REFDV4
REFDV3
REFDV2
REFDV1
REFDV0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-5. CRG Reference Divider Register (REFDV)
Read: Anytime
Write: Anytime except when PLLSEL = 1
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NOTE
Write to this register initializes the lock detector bit and the track detector
bit.
7.3.2.3
Reserved Register (CTFLG)
This register is reserved for factory testing of the CRG module and is not available in normal modes.
Module Base +0x_02
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 7-6. Reserved Register (CTFLG)
Read: Always reads 0x_00 in normal modes
Write: Unimplemented in normal modes
NOTE
Writing to this register when in special mode can alter the CRG
fucntionality.
7.3.2.4
CRG Flags Register (CRGFLG)
This register provides CRG status bits and flags.
Module Base +0x_03
7
R
W
Reset
6
5
4
RTIF
PORF
LVRF
LOCKIF
0
1
2
0
3
2
LOCK
TRACK
0
0
1
SCMIF
0
0
SCM
0
1. PORF is set to 1 when a power on reset occurs. Unaffected by system reset.
2. LVRF is set to 1 when a low-voltage reset occurs. Unaffected by system reset.
= Unimplemented or Reserved
Figure 7-7. CRG Flags Register (CRGFLG)
Read: Anytime
Write: Refer to each bit for individual write conditions
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Table 7-2. CRGFLG Field Descriptions
Field
Description
7
RTIF
Real Time Interrupt Flag — RTIF is set to 1 at the end of the RTI period. This flag can only be cleared by writing
a 1. Writing a 0 has no effect. If enabled (RTIE = 1), RTIF causes an interrupt request.
0 RTI time-out has not yet occurred.
1 RTI time-out has occurred.
6
PORF
Power on Reset Flag — PORF is set to 1 when a power on reset occurs. This flag can only be cleared by writing
a 1. Writing a 0 has no effect.
0 Power on reset has not occurred.
1 Power on reset has occurred.
5
LVRF
Low Voltage Reset Flag — If low voltage reset feature is not available (see device specification) LVRF always
reads 0. LVRF is set to 1 when a low voltage reset occurs. This flag can only be cleared by writing a 1. Writing
a 0 has no effect.
0 Low voltage reset has not occurred.
1 Low voltage reset has occurred.
4
LOCKIF
PLL Lock Interrupt Flag — LOCKIF is set to 1 when LOCK status bit changes. This flag can only be cleared
by writing a 1. Writing a 0 has no effect.If enabled (LOCKIE = 1), LOCKIF causes an interrupt request.
0 No change in LOCK bit.
1 LOCK bit has changed.
3
LOCK
Lock Status Bit — LOCK reflects the current state of PLL lock condition. This bit is cleared in self clock mode.
Writes have no effect.
0 PLL VCO is not within the desired tolerance of the target frequency.
1 PLL VCO is within the desired tolerance of the target frequency.
2
TRACK
Track Status Bit — TRACK reflects the current state of PLL track condition. This bit is cleared in self clock
mode. Writes have no effect.
0 Acquisition mode status.
1Tracking mode status.
1
SCMIF
Self Clock Mode Interrupt Flag — SCMIF is set to 1 when SCM status bit changes. This flag can only be
cleared by writing a 1. Writing a 0 has no effect. If enabled (SCMIE = 1), SCMIF causes an interrupt request.
0 No change in SCM bit.
1 SCM bit has changed.
0
SCM
Self Clock Mode Status Bit — SCM reflects the current clocking mode. Writes have no effect.
0 MCU is operating normally with OSCCLK available.
1 MCU is operating in self clock mode with OSCCLK in an unknown state. All clocks are derived from PLLCLK
running at its minimum frequency fSCM.
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Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.3.2.5
CRG Interrupt Enable Register (CRGINT)
This register enables CRG interrupt requests.
Module Base +0x_04
7
R
W
Reset
6
RTIE
ILAF
0
1
5
0
0
4
LOCKIE
0
3
2
0
0
0
0
1
SCMIE
0
0
0
0
1. ILAF is set to 1 when an illegal address reset occurs. Unaffected by system reset. Cleared by power on or low
voltage reset.
= Unimplemented or Reserved
Figure 7-8. CRG Interrupt Enable Register (CRGINT)
Read: Anytime
Write: Anytime
Table 7-3. CRGINT Field Descriptions
Field
Description
7
RTIE
Real Time Interrupt Enable Bit
0 Interrupt requests from RTI are disabled.
1 Interrupt will be requested whenever RTIF is set.
6
ILAF
Illegal Address Reset Flag — ILAF is set to 1 when an illegal address reset occurs. Refer to S12XMMC Block
Guide for details. This flag can only be cleared by writing a 1. Writing a 0 has no effect.
0 Illegal address reset has not occurred.
1 Illegal address reset has occurred.
4
LOCKIE
Lock Interrupt Enable Bit
0 LOCK interrupt requests are disabled.
1 Interrupt will be requested whenever LOCKIF is set.
1
SCMIE
Self Clock Mode Interrupt Enable Bit
0 SCM interrupt requests are disabled.
1 Interrupt will be requested whenever SCMIF is set.
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7.3.2.6
CRG Clock Select Register (CLKSEL)
This register controls CRG clock selection. Refer to Figure 7-17 for more details on the effect of each bit.
Module Base +0x_05
7
R
W
Reset
6
PLLSEL
PSTP
0
0
5
4
0
0
0
0
3
PLLWAI
0
2
0
1
0
RTIWAI
COPWAI
0
0
0
= Unimplemented or Reserved
Figure 7-9. CRG Clock Select Register (CLKSEL)
Read: Anytime
Write: Refer to each bit for individual write conditions
Table 7-4. CLKSEL Field Descriptions
Field
Description
7
PLLSEL
PLL Select Bit — Write anytime. Writing a1 when LOCK = 0 and AUTO = 1, or TRACK = 0 and AUTO = 0 has
no effect This prevents the selection of an unstable PLLCLK as SYSCLK. PLLSEL bit is cleared when the MCU
enters self clock mode, Stop mode or wait mode with PLLWAI bit set.
It is recommended to read back the PLLSEL bit to make sure PLLCLK has really been selected as
SYSCLK, as LOCK status bit could theoretically change at the very moment writing the PLLSEL bit.
0 System clocks are derived from OSCCLK (fBUS = fOSC / 2).
1 System clocks are derived from PLLCLK (fBUS = fPLL / 2).
6
PSTP
Pseudo Stop Bit
Write: Anytime
This bit controls the functionality of the oscillator during stop mode.
0 Oscillator is disabled in stop mode.
1 Oscillator continues to run in stop mode (pseudo stop).
Note: Pseudo stop mode allows for faster STOP recovery and reduces the mechanical stress and aging of the
resonator in case of frequent STOP conditions at the expense of a slightly increased power consumption.
3
PLLWAI
PLL Stops in Wait Mode Bit
Write: Anytime
If PLLWAI is set, the CRG will clear the PLLSEL bit before entering wait mode. The PLLON bit remains set during
wait mode, but the PLL is powered down. Upon exiting wait mode, the PLLSEL bit has to be set manually if PLL
clock is required.
While the PLLWAI bit is set, the AUTO bit is set to 1 in order to allow the PLL to automatically lock on the selected
target frequency after exiting wait mode.
0 PLL keeps running in wait mode.
1 PLL stops in wait mode.
1
RTIWAI
RTI Stops in Wait Mode Bit
Write: Anytime
0 RTI keeps running in wait mode.
1 RTI stops and initializes the RTI dividers whenever the part goes into wait mode.
0
COPWAI
COP Stops in Wait Mode Bit
Normal modes: Write once
Special modes: Write anytime
0 COP keeps running in wait mode.
1 COP stops and initializes the COP counter whenever the part goes into wait mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
341
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.3.2.7
CRG PLL Control Register (PLLCTL)
This register controls the PLL functionality.
Module Base +0x_06
R
W
Reset
7
6
5
4
3
2
1
0
CME
PLLON
AUTO
ACQ
FSTWKP
PRE
PCE
SCME
1
1
1
1
0
0
0
1
Figure 7-10. CRG PLL Control Register (PLLCTL)
Read: Anytime
Write: Refer to each bit for individual write conditions
Table 7-5. PLLCTL Field Descriptions
Field
Description
7
CME
Clock Monitor Enable Bit — CME enables the clock monitor. Write anytime except when SCM = 1.
0 Clock monitor is disabled.
1 Clock monitor is enabled. Slow or stopped clocks will cause a clock monitor reset sequence or self clock
mode.
Note: Operating with CME = 0 will not detect any loss of clock. In case of poor clock quality, this could cause
unpredictable operation of the MCU!
Note: In stop mode (PSTP = 0) the clock monitor is disabled independently of the CME bit setting and any loss
of external clock will not be detected. Also after wake-up from stop mode (PSTP = 0) with fast wake-up
enabled (FSTWKP = 1) the clock monitor is disabled independently of the CME bit setting and any loss
of external clock will not be detected.
6
PLLON
Phase Lock Loop On Bit — PLLON turns on the PLL circuitry. In self clock mode, the PLL is turned on, but the
PLLON bit reads the last latched value. Write anytime except when PLLSEL = 1.
0 PLL is turned off.
1 PLL is turned on. If AUTO bit is set, the PLL will lock automatically.
5
AUTO
Automatic Bandwidth Control Bit — AUTO selects either the high bandwidth (acquisition) mode or the low
bandwidth (tracking) mode depending on how close to the desired frequency the VCO is running. Write anytime
except when PLLWAI = 1, because PLLWAI sets the AUTO bit to 1.
0 Automatic mode control is disabled and the PLL is under software control, using ACQ bit.
1 Automatic mode control is enabled and ACQ bit has no effect.
4
ACQ
Acquisition Bit
Write anytime. If AUTO=1 this bit has no effect.
0 Low bandwidth filter is selected.
1 High bandwidth filter is selected.
3
FSTWKP
Fast Wake-up from Full Stop Bit — FSTWKP enables fast wake-up from full stop mode. Write anytime. If
self-clock mode is disabled (SCME = 0) this bit has no effect.
0 Fast wake-up from full stop mode is disabled.
1 Fast wake-up from full stop mode is enabled.
When waking up from full stop mode the system will immediately resume operation i self-clock mode (see
Section 7.4.1.4, “Clock Quality Checker”). The SCMIF flag will not be set. The system will remain in self-clock
mode with oscillator and clock monitor disabled until FSTWKP bit is cleared. The clearing of FSTWKP will
start the oscillator, the clock monitor and the clock quality check. If the clock quality check is successful, the
CRG will switch all system clocks to OSCCLK. The SCMIF flag will be set. See application examples in
Figure 7-23 and Figure 7-24.
MC9S12XHZ512 Data Sheet, Rev. 1.06
342
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-5. PLLCTL Field Descriptions (continued)
Field
Description
2
PRE
RTI Enable during Pseudo Stop Bit — PRE enables the RTI during pseudo stop mode. Write anytime.
0 RTI stops running during pseudo stop mode.
1 RTI continues running during pseudo stop mode.
Note: If the PRE bit is cleared the RTI dividers will go static while pseudo stop mode is active. The RTI dividers
will not initialize like in wait mode with RTIWAI bit set.
1
PCE
COP Enable during Pseudo Stop Bit — PCE enables the COP during pseudo stop mode. Write anytime.
0 COP stops running during pseudo stop mode
1 COP continues running during pseudo stop mode
Note: If the PCE bit is cleared, the COP dividers will go static while pseudo stop mode is active. The COP
dividers will not initialize like in wait mode with COPWAI bit set.
0
SCME
7.3.2.8
Self Clock Mode Enable Bit
Normal modes: Write once
Special modes: Write anytime
SCME can not be cleared while operating in self clock mode (SCM = 1).
0 Detection of crystal clock failure causes clock monitor reset (see Section 7.5.2, “Clock Monitor Reset”).
1 Detection of crystal clock failure forces the MCU in self clock mode (see Section 7.4.2.2, “Self Clock Mode”).
CRG RTI Control Register (RTICTL)
This register selects the timeout period for the real time interrupt.
Module Base +0x_07
R
W
Reset
7
6
5
4
3
2
1
0
RTDEC
RTR6
RTR5
RTR4
RTR3
RTR2
RTR1
RTR0
0
0
0
0
0
0
0
0
Figure 7-11. CRG RTI Control Register (RTICTL)
Read: Anytime
Write: Anytime
NOTE
A write to this register initializes the RTI counter.
Table 7-6. RTICTL Field Descriptions
Field
Description
7
RTDEC
Decimal or Binary Divider Select Bit — RTDEC selects decimal or binary based prescaler values.
0 Binary based divider value. See Table 7-7
1 Decimal based divider value. See Table 7-8
6–4
RTR[6:4]
Real Time Interrupt Prescale Rate Select Bits — These bits select the prescale rate for the RTI. See Table 7-7
and Table 7-8.
3–0
RTR[3:0]
Real Time Interrupt Modulus Counter Select Bits — These bits select the modulus counter target value to
provide additional granularity.Table 7-7 and Table 7-8 show all possible divide values selectable by the RTICTL
register. The source clock for the RTI is OSCCLK.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
343
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-7. RTI Frequency Divide Rates for RTDEC = 0
RTR[6:4] =
RTR[3:0]
000
(OFF)
001
(210)
010
(211)
011
(212)
100
(213)
101
(214)
110
(215)
111
(216)
0000 (÷1)
OFF*
210
211
212
213
214
215
216
0001 (÷2)
OFF
2x210
2x211
2x212
2x213
2x214
2x215
2x216
0010 (÷3)
OFF
3x210
3x211
3x212
3x213
3x214
3x215
3x216
0011 (÷4)
OFF
4x210
4x211
4x212
4x213
4x214
4x215
4x216
0100 (÷5)
OFF
5x210
5x211
5x212
5x213
5x214
5x215
5x216
0101 (÷6)
OFF
6x210
6x211
6x212
6x213
6x214
6x215
6x216
0110 (÷7)
OFF
7x210
7x211
7x212
7x213
7x214
7x215
7x216
0111 (÷8)
OFF
8x210
8x211
8x212
8x213
8x214
8x215
8x216
1000 (÷9)
OFF
9x210
9x211
9x212
9x213
9x214
9x215
9x216
1001 (÷10)
OFF
10x210
10x211
10x212
10x213
10x214
10x215
10x216
1010 (÷11)
OFF
11x210
11x211
11x212
11x213
11x214
11x215
11x216
1011 (÷12)
OFF
12x210
12x211
12x212
12x213
12x214
12x215
12x216
1100 (÷13)
OFF
13x210
13x211
13x212
13x213
13x214
13x215
13x216
1101 (÷14)
OFF
14x210
14x211
14x212
14x213
14x214
14x215
14x216
1110 (÷15)
OFF
15x210
15x211
15x212
15x213
15x214
15x215
15x216
1111 (÷16)
OFF
16x210
16x211
16x212
16x213
16x214
16x215
16x216
* Denotes the default value out of reset.This value should be used to disable the RTI to ensure future backwards compatibility.
MC9S12XHZ512 Data Sheet, Rev. 1.06
344
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-8. RTI Frequency Divide Rates for RTDEC = 1
RTR[6:4] =
RTR[3:0]
000
(1x103)
001
(2x103)
010
(5x103)
011
(10x103)
100
(20x103)
101
(50x103)
110
(100x103)
111
(200x103)
0000 (÷1)
1x103
2x103
5x103
10x103
20x103
50x103
100x103
200x103
0001 (÷2)
2x103
4x103
10x103
20x103
40x103
100x103
200x103
400x103
0010 (÷3)
3x103
6x103
15x103
30x103
60x103
150x103
300x103
600x103
0011 (÷4)
4x103
8x103
20x103
40x103
80x103
200x103
400x103
800x103
0100 (÷5)
5x103
10x103
25x103
50x103
100x103
250x103
500x103
1x106
0101 (÷6)
6x103
12x103
30x103
60x103
120x103
300x103
600x103
1.2x106
0110 (÷7)
7x103
14x103
35x103
70x103
140x103
350x103
700x103
1.4x106
0111 (÷8)
8x103
16x103
40x103
80x103
160x103
400x103
800x103
1.6x106
1000 (÷9)
9x103
18x103
45x103
90x103
180x103
450x103
900x103
1.8x106
1001 (÷10)
10 x103
20x103
50x103
100x103
200x103
500x103
1x106
2x106
1010 (÷11)
11 x103
22x103
55x103
110x103
220x103
550x103
1.1x106
2.2x106
1011 (÷12)
12x103
24x103
60x103
120x103
240x103
600x103
1.2x106
2.4x106
1100 (÷13)
13x103
26x103
65x103
130x103
260x103
650x103
1.3x106
2.6x106
1101 (÷14)
14x103
28x103
70x103
140x103
280x103
700x103
1.4x106
2.8x106
1110 (÷15)
15x103
30x103
75x103
150x103
300x103
750x103
1.5x106
3x106
1111 (÷16)
16x103
32x103
80x103
160x103
320x103
800x103
1.6x106
3.2x106
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
345
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.3.2.9
CRG COP Control Register (COPCTL)
This register controls the COP (computer operating properly) watchdog.
Module Base +0x_08
7
R
W
WCOP
Reset1
6
RSBCK
0
5
4
3
0
0
0
0
0
WRTMASK
0
2
1
0
CR2
CR1
CR0
1. Refer to Device User Guide (Section: CRG) for reset values of WCOP, CR2, CR1, and CR0.
= Unimplemented or Reserved
Figure 7-12. CRG COP Control Register (COPCTL)
Read: Anytime
Write:
1. RSBCK: Anytime in special modes; write to “1” but not to “0” in all other modes
2. WCOP, CR2, CR1, CR0:
— Anytime in special modes
— Write once in all other modes
Writing CR[2:0] to “000” has no effect, but counts for the “write once” condition.
Writing WCOP to “0” has no effect, but counts for the “write once” condition.
The COP time-out period is restarted if one these two conditions is true:
1. Writing a nonzero value to CR[2:0] (anytime in special modes, once in all other modes) with
WRTMASK = 0.
or
2. Changing RSBCK bit from “0” to “1”.
Table 7-9. COPCTL Field Descriptions
Field
Description
7
WCOP
Window COP Mode Bit — When set, a write to the ARMCOP register must occur in the last 25% of the selected
period. A write during the first 75% of the selected period will reset the part. As long as all writes occur during
this window, 0x_55 can be written as often as desired. Once 0x_AA is written after the 0x_55, the time-out logic
restarts and the user must wait until the next window before writing to ARMCOP. Table 7-10 shows the duration
of this window for the seven available COP rates.
0 Normal COP operation
1 Window COP operation
6
RSBCK
COP and RTI Stop in Active BDM Mode Bit
0 Allows the COP and RTI to keep running in active BDM mode.
1 Stops the COP and RTI counters whenever the part is in active BDM mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
346
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-9. COPCTL Field Descriptions (continued)
Field
Description
5
WRTMASK
Write Mask for WCOP and CR[2:0] Bit — This write-only bit serves as a mask for the WCOP and CR[2:0] bits
while writing the COPCTL register. It is intended for BDM writing the RSBCK without touching the contents of
WCOP and CR[2:0].
0 Write of WCOP and CR[2:0] has an effect with this write of COPCTL
1 Write of WCOP and CR[2:0] has no effect with this write of COPCTL. (Does not count for “write once”.)
2–0
CR[1:0]
COP Watchdog Timer Rate Select — These bits select the COP time-out rate (see Table 7-10). The COP
time-out period is OSCCLK period divided by CR[2:0] value. Writing a nonzero value to CR[2:0] enables the
COP counter and starts the time-out period. A COP counter time-out causes a system reset. This can be
avoided by periodically (before time-out) reinitializing the COP counter via the ARMCOP register.
While all of the following three conditions are true the CR[2:0], WCOP bits are ignored and the COP operates
at highest time-out period (2 24 cycles) in normal COP mode (Window COP mode disabled):
1) COP is enabled (CR[2:0] is not 000)
2) BDM mode active
3) RSBCK = 0
4) Operation in emulation or special modes
Table 7-10. COP Watchdog Rates1
1
CR2
CR1
CR0
OSCCLK
Cycles to Time-out
0
0
0
COP disabled
0
0
1
214
0
1
0
216
0
1
1
218
1
0
0
220
1
0
1
222
1
1
0
223
1
1
1
224
OSCCLK cycles are referenced from the previous COP time-out reset
(writing 0x_55/0x_AA to the ARMCOP register)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
347
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.3.2.10
Reserved Register (FORBYP)
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special
modes can alter the CRG’s functionality.
Module Base +0x_09
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 7-13. Reserved Register (FORBYP)
Read: Always read 0x_00 except in special modes
Write: Only in special modes
7.3.2.11
Reserved Register (CTCTL)
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special test
modes can alter the CRG’s functionality.
Module Base +0x_0A
R
7
6
5
4
3
2
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 7-14. Reserved Register (CTCTL)
Read: always read 0x_80 except in special modes
Write: only in special modes
MC9S12XHZ512 Data Sheet, Rev. 1.06
348
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.3.2.12
CRG COP Timer Arm/Reset Register (ARMCOP)
This register is used to restart the COP time-out period.
Module Base +0x_0B
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
0
0
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Reset
Figure 7-15. ARMCOP Register Diagram
Read: Always reads 0x_00
Write: Anytime
When the COP is disabled (CR[2:0] = “000”) writing to this register has no effect.
When the COP is enabled by setting CR[2:0] nonzero, the following applies:
Writing any value other than 0x_55 or 0x_AA causes a COP reset. To restart the COP time-out
period you must write 0x_55 followed by a write of 0x_AA. Other instructions may be executed
between these writes but the sequence (0x_55, 0x_AA) must be completed prior to COP end of
time-out period to avoid a COP reset. Sequences of 0x_55 writes or sequences of 0x_AA writes
are allowed. When the WCOP bit is set, 0x_55 and 0x_AA writes must be done in the last 25% of
the selected time-out period; writing any value in the first 75% of the selected period will cause a
COP reset.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
349
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.4
Functional Description
7.4.1
Functional Blocks
7.4.1.1
Phase Locked Loop (PLL)
The PLL is used to run the MCU from a different time base than the incoming OSCCLK. For increased
flexibility, OSCCLK can be divided in a range of 1 to 16 to generate the reference frequency. This offers
a finer multiplication granularity. The PLL can multiply this reference clock by a multiple of 2, 4, 6,...
126,128 based on the SYNR register.
[ SYNR + 1 ]
PLLCLK = 2 × OSCCLK × -----------------------------------[ REFDV + 1 ]
CAUTION
Although it is possible to set the two dividers to command a very high clock
frequency, do not exceed the specified bus frequency limit for the MCU.
If (PLLSEL = 1), Bus Clock = PLLCLK / 2
The PLL is a frequency generator that operates in either acquisition mode or tracking mode, depending on
the difference between the output frequency and the target frequency. The PLL can change between
acquisition and tracking modes either automatically or manually.
The VCO has a minimum operating frequency, which corresponds to the self clock mode frequency fSCM.
REFERENCE
REFDV <5:0>
EXTAL
REDUCED
CONSUMPTION
OSCILLATOR
OSCCLK
FEEDBACK
REFERENCE
PROGRAMMABLE
DIVIDER
XTAL
CRYSTAL
MONITOR
supplied by:
LOOP
PROGRAMMABLE
DIVIDER
LOCK
LOCK
DETECTOR
VDDPLL/VSSPLL
PDET
PHASE
DETECTOR
UP
DOWN
CPUMP
VCO
VDDPLL
LOOP
FILTER
SYN <5:0>
VDDPLL/VSSPLL
XFC
PIN
PLLCLK
VDD/VSS
Figure 7-16. PLL Functional Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
350
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.4.1.1.1
PLL Operation
The oscillator output clock signal (OSCCLK) is fed through the reference programmable divider and is
divided in a range of 1 to 64 (REFDV + 1) to output the REFERENCE clock. The VCO output clock,
(PLLCLK) is fed back through the programmable loop divider and is divided in a range of 2 to 128 in
increments of [2 x (SYNR + 1)] to output the FEEDBACK clock. Figure 7-16.
The phase detector then compares the FEEDBACK clock, with the REFERENCE clock. Correction pulses
are generated based on the phase difference between the two signals. The loop filter then slightly alters the
DC voltage on the external filter capacitor connected to XFC pin, based on the width and direction of the
correction pulse. The filter can make fast or slow corrections depending on its mode, as described in the
next subsection. The values of the external filter network and the reference frequency determine the speed
of the corrections and the stability of the PLL.
The minimum VCO frequency is reached with the XFC pin forced to VDDPLL. This is the self clock mode
frequency.
7.4.1.1.2
Acquisition and Tracking Modes
The lock detector compares the frequencies of the FEEDBACK clock, and the REFERENCE clock.
Therefore, the speed of the lock detector is directly proportional to the final reference frequency. The
circuit determines the mode of the PLL and the lock condition based on this comparison.
The PLL filter can be manually or automatically configured into one of two possible operating modes:
• Acquisition mode
In acquisition mode, the filter can make large frequency corrections to the VCO. This mode is used
at PLL start-up or when the PLL has suffered a severe noise hit and the VCO frequency is far off
the desired frequency. When in acquisition mode, the TRACK status bit is cleared in the CRGFLG
register.
• Tracking mode
In tracking mode, the filter makes only small corrections to the frequency of the VCO. PLL jitter
is much lower in tracking mode, but the response to noise is also slower. The PLL enters tracking
mode when the VCO frequency is nearly correct and the TRACK bit is set in the CRGFLG register.
The PLL can change the bandwidth or operational mode of the loop filter manually or automatically.
In automatic bandwidth control mode (AUTO = 1), the lock detector automatically switches between
acquisition and tracking modes. Automatic bandwidth control mode also is used to determine when the
PLL clock (PLLCLK) is safe to use as the source for the system and core clocks. If PLL LOCK interrupt
requests are enabled, the software can wait for an interrupt request and then check the LOCK bit. If
interrupt requests are disabled, software can poll the LOCK bit continuously (during PLL start-up, usually)
or at periodic intervals. In either case, only when the LOCK bit is set, is the PLLCLK clock safe to use as
the source for the system and core clocks. If the PLL is selected as the source for the system and core
clocks and the LOCK bit is clear, the PLL has suffered a severe noise hit and the software must take
appropriate action, depending on the application.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
351
Chapter 7 Clocks and Reset Generator (S12CRGV6)
The following conditions apply when the PLL is in automatic bandwidth control mode (AUTO = 1):
• The TRACK bit is a read-only indicator of the mode of the filter.
• The TRACK bit is set when the VCO frequency is within a certain tolerance, ∆trk, and is clear when
the VCO frequency is out of a certain tolerance, ∆unt.
• The LOCK bit is a read-only indicator of the locked state of the PLL.
• The LOCK bit is set when the VCO frequency is within a certain tolerance, ∆Lock, and is cleared
when the VCO frequency is out of a certain tolerance, ∆unl.
• Interrupt requests can occur if enabled (LOCKIE = 1) when the lock condition changes, toggling
the LOCK bit.
The PLL can also operate in manual mode (AUTO = 0). Manual mode is used by systems that do not
require an indicator of the lock condition for proper operation. Such systems typically operate well below
the maximum system frequency (fsys) and require fast start-up. The following conditions apply when in
manual mode:
• ACQ is a writable control bit that controls the mode of the filter. Before turning on the PLL in
manual mode, the ACQ bit should be asserted to configure the filter in acquisition mode.
• After turning on the PLL by setting the PLLON bit software must wait a given time (tacq) before
entering tracking mode (ACQ = 0).
• After entering tracking mode software must wait a given time (tal) before selecting the PLLCLK
as the source for system and core clocks (PLLSEL = 1).
7.4.1.2
System Clocks Generator
PLLSEL or SCM
PHASE
LOCK
LOOP
PLLCLK
STOP
1
SYSCLK
÷2
SCM
EXTAL
1
OSCILLATOR
CORE CLOCK
0
WAIT(RTIWAI),
STOP(PSTP,PRE),
RTI ENABLE
BUS CLOCK
RTI
OSCCLK
0
XTAL
CLOCK PHASE
GENERATOR
WAIT(COPWAI),
STOP(PSTP,PCE),
COP ENABLE
COP
CLOCK
MONITOR
GATING
CONDITION
STOP
OSCILLATOR
CLOCK
= CLOCK GATE
Figure 7-17. System Clocks Generator
MC9S12XHZ512 Data Sheet, Rev. 1.06
352
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
The clock generator creates the clocks used in the MCU (see Figure 7-17). The gating condition placed on
top of the individual clock gates indicates the dependencies of different modes (STOP, WAIT) and the
setting of the respective configuration bits.
The peripheral modules use the bus clock. Some peripheral modules also use the oscillator clock. The
memory blocks use the bus clock. If the MCU enters self clock mode (see Section 7.4.2.2, “Self Clock
Mode”) oscillator clock source is switched to PLLCLK running at its minimum frequency fSCM. The bus
clock is used to generate the clock visible at the ECLK pin. The core clock signal is the clock for the CPU.
The core clock is twice the bus clock as shown in Figure 7-18. But note that a CPU cycle corresponds to
one bus clock.
PLL clock mode is selected with PLLSEL bit in the CLKSEL registerr. When selected, the PLL output
clock drives SYSCLK for the main system including the CPU and peripherals. The PLL cannot be turned
off by clearing the PLLON bit, if the PLL clock is selected. When PLLSEL is changed, it takes a maximum
of 4 OSCCLK plus 4 PLLCLK cycles to make the transition. During the transition, all clocks freeze and
CPU activity ceases.
CORE CLOCK
BUS CLOCK / ECLK
Figure 7-18. Core Clock and Bus Clock Relationship
7.4.1.3
Clock Monitor (CM)
If no OSCCLK edges are detected within a certain time, the clock monitor within the oscillator block
generates a clock monitor fail event. The CRG then asserts self clock mode or generates a system reset
depending on the state of SCME bit. If the clock monitor is disabled or the presence of clocks is detected
no failure is indicated by the oscillator block.The clock monitor function is enabled/disabled by the CME
control bit.
7.4.1.4
Clock Quality Checker
The clock monitor performs a coarse check on the incoming clock signal. The clock quality checker
provides a more accurate check in addition to the clock monitor.
A clock quality check is triggered by any of the following events:
• Power on reset (POR)
• Low voltage reset (LVR)
• Wake-up from full stop mode (exit full stop)
• Clock monitor fail indication (CM fail)
A time window of 50,000 VCO clock cycles1 is called check window.
1. VCO clock cycles are generated by the PLL when running at minimum frequency fSCM.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
353
Chapter 7 Clocks and Reset Generator (S12CRGV6)
A number greater equal than 4096 rising OSCCLK edges within a check window is called osc ok. Note that
osc ok immediately terminates the current check window. See Figure 7-19 as an example.
check window
1
3
2
50000
49999
VCO
Clock
1
2
3
4
5
4096
OSCCLK
4095
osc ok
Figure 7-19. Check Window Example
The sequence for clock quality check is shown in Figure 7-20.
CM fail
Clock OK
no
exit full stop
POR
SCME = 1 &
FSTWKP = 1
?
LVR
yes
num = 0
FSTWKP = 0
?
Enter SCM
yes
no
Clock Monitor Reset
Enter SCM
num = 50
yes
check window
SCM
active?
num=num–1
yes
osc ok
num = 0
no
no
?
num > 0
?
yes
no
SCME=1
?
no
yes
SCM
active?
yes
Switch to OSCCLK
no
Exit SCM
Figure 7-20. Sequence for Clock Quality Check
MC9S12XHZ512 Data Sheet, Rev. 1.06
354
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
NOTE
Remember that in parallel to additional actions caused by self clock mode
or clock monitor reset1 handling the clock quality checker continues to
check the OSCCLK signal.
The clock quality checker enables the PLL and the voltage regulator
(VREG) anytime a clock check has to be performed. An ongoing clock
quality check could also cause a running PLL (fSCM) and an active VREG
during pseudo stop mode or wait mode.
7.4.1.5
Computer Operating Properly Watchdog (COP)
The COP (free running watchdog timer) enables the user to check that a program is running and
sequencing properly. When the COP is being used, software is responsible for keeping the COP from
timing out. If the COP times out it is an indication that the software is no longer being executed in the
intended sequence; thus a system reset is initiated (see Section 7.4.1.5, “Computer Operating Properly
Watchdog (COP)”). The COP runs with a gated OSCCLK. Three control bits in the COPCTL register
allow selection of seven COP time-out periods.
When COP is enabled, the program must write 0x_55 and 0x_AA (in this order) to the ARMCOP register
during the selected time-out period. Once this is done, the COP time-out period is restarted. If the program
fails to do this and the COP times out, the part will reset. Also, if any value other than 0x_55 or 0x_AA is
written, the part is immediately reset.
Windowed COP operation is enabled by setting WCOP in the COPCTL register. In this mode, writes to
the ARMCOP register to clear the COP timer must occur in the last 25% of the selected time-out period.
A premature write will immediately reset the part.
If PCE bit is set, the COP will continue to run in pseudo stop mode.
7.4.1.6
Real Time Interrupt (RTI)
The RTI can be used to generate a hardware interrupt at a fixed periodic rate. If enabled (by setting
RTIE = 1), this interrupt will occur at the rate selected by the RTICTL register. The RTI runs with a gated
OSCCLK. At the end of the RTI time-out period the RTIF flag is set to 1 and a new RTI time-out period
starts immediately.
A write to the RTICTL register restarts the RTI time-out period.
If the PRE bit is set, the RTI will continue to run in pseudo stop mode.
7.4.2
7.4.2.1
Operating Modes
Normal Mode
The CRG block behaves as described within this specification in all normal modes.
1. A Clock Monitor Reset will always set the SCME bit to logical 1.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
355
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.4.2.2
Self Clock Mode
The VCO has a minimum operating frequency, fSCM. If the external clock frequency is not available due
to a failure or due to long crystal start-up time, the bus clock and the core clock are derived from the VCO
running at minimum operating frequency; this mode of operation is called self clock mode. This requires
CME = 1 and SCME = 1. If the MCU was clocked by the PLL clock prior to entering self clock mode, the
PLLSEL bit will be cleared. If the external clock signal has stabilized again, the CRG will automatically
select OSCCLK to be the system clock and return to normal mode. Section 7.4.1.4, “Clock Quality
Checker” for more information on entering and leaving self clock mode.
NOTE
In order to detect a potential clock loss the CME bit should be always
enabled (CME = 1)!
If CME bit is disabled and the MCU is configured to run on PLL clock
(PLLCLK), a loss of external clock (OSCCLK) will not be detected and will
cause the system clock to drift towards the VCO’s minimum frequency
fSCM. As soon as the external clock is available again the system clock
ramps up to its PLL target frequency. If the MCU is running on external
clock any loss of clock will cause the system to go static.
7.4.3
Low Power Options
This section summarizes the low power options available in the CRG.
7.4.3.1
Run Mode
The RTI can be stopped by setting the associated rate select bits to 0.
The COP can be stopped by setting the associated rate select bits to 0.
7.4.3.2
Wait Mode
The WAI instruction puts the MCU in a low power consumption stand-by mode depending on setting of
the individual bits in the CLKSEL register. All individual wait mode configuration bits can be superposed.
This provides enhanced granularity in reducing the level of power consumption during wait mode.
Table 7-11 lists the individual configuration bits and the parts of the MCU that are affected in wait mode
.
Table 7-11. MCU Configuration During Wait Mode
PLLWAI
RTIWAI
COPWAI
PLL
Stopped
—
—
RTI
—
Stopped
—
COP
—
—
Stopped
After executing the WAI instruction the core requests the CRG to switch MCU into wait mode. The CRG
then checks whether the PLLWAI bit is asserted (Figure 7-21). Depending on the configuration, the CRG
switches the system and core clocks to OSCCLK by clearing the PLLSEL bit and disables the PLL. As
soon as all clocks are switched off wait mode is active.
MC9S12XHZ512 Data Sheet, Rev. 1.06
356
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
CPU Req’s
Wait Mode.
PLLWAI=1
?
No
Yes
Clear PLLSEL,
Disable PLL
No
Enter
Wait Mode
CME=1
?
Wait Mode left
due to external reset
No
Yes
Exit Wait w.
ext.RESET
CM Fail
?
INT
?
Yes
No
Yes
Exit Wait w.
CMRESET
No
SCME=1
?
Yes
SCMIE=1
?
Generate
SCM Interrupt
(Wakeup from Wait)
No
Exit
Wait Mode
Yes
Exit
Wait Mode
SCM=1
?
No
Yes
Enter
SCM
Enter
SCM
Continue w.
Normal OP
Figure 7-21. Wait Mode Entry/Exit Sequence
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
357
Chapter 7 Clocks and Reset Generator (S12CRGV6)
There are four different scenarios for the CRG to restart the MCU from wait mode:
• External reset
• Clock monitor reset
• COP reset
• Any interrupt
If the MCU gets an external reset or COP reset during wait mode active, the CRG asynchronously restores
all configuration bits in the register space to its default settings and starts the reset generator. After
completing the reset sequence processing begins by fetching the normal or COP reset vector. Wait mode
is left and the MCU is in run mode again.
If the clock monitor is enabled (CME = 1) the MCU is able to leave wait mode when loss of
oscillator/external clock is detected by a clock monitor fail. If the SCME bit is not asserted the CRG
generates a clock monitor fail reset (CMRESET). The CRG’s behavior for CMRESET is the same
compared to external reset, but another reset vector is fetched after completion of the reset sequence. If the
SCME bit is asserted the CRG generates a SCM interrupt if enabled (SCMIE = 1). After generating the
interrupt the CRG enters self-clock mode and starts the clock quality checker (Section 7.4.1.4, “Clock
Quality Checker”). Then the MCU continues with normal operation.If the SCM interrupt is blocked by
SCMIE = 0, the SCMIF flag will be asserted and clock quality checks will be performed but the MCU will
not wake-up from wait-mode.
If any other interrupt source (e.g., RTI) triggers exit from wait mode, the MCU immediately continues with
normal operation. If the PLL has been powered-down during wait mode, the PLLSEL bit is cleared and
the MCU runs on OSCCLK after leaving wait mode. The software must manually set the PLLSEL bit
again, in order to switch system and core clocks to the PLLCLK.
If wait mode is entered from self-clock mode the CRG will continue to check the clock quality until clock
check is successful. The PLL and voltage regulator (VREG) will remain enabled.
Table 7-12 summarizes the outcome of a clock loss while in wait mode.
7.4.3.3
System Stop Mode
All clocks are stopped in STOP mode, dependent of the setting of the PCE, PRE, and PSTP bit. The
oscillator is disabled in STOP mode unless the PSTP bit is set. All counters and dividers remain frozen but
do not initialize. If the PRE or PCE bits are set, the RTI or COP continues to run in pseudo stop mode. In
addition to disabling system and core clocks the CRG requests other functional units of the MCU (e.g.,
voltage-regulator) to enter their individual power saving modes (if available). This is the main difference
between pseudo stop mode and wait mode.
If the PLLSEL bit is still set when entering stop mode, the CRG will switch the system and core clocks to
OSCCLK by clearing the PLLSEL bit. Then the CRG disables the PLL, disables the core clock and finally
disables the remaining system clocks. As soon as all clocks are switched off, stop mode is active.
If pseudo stop mode (PSTP = 1) is entered from self-clock mode, the CRG will continue to check the clock
quality until clock check is successful. The PLL and the voltage regulator (VREG) will remain enabled. If
full stop mode (PSTP = 0) is entered from self-clock mode, an ongoing clock quality check will be
stopped. A complete timeout window check will be started when stop mode is left again.
Wake-up from stop mode also depends on the setting of the PSTP bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
358
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-12. Outcome of Clock Loss in Wait Mode
CME
SCME
SCMIE
0
X
X
Clock failure -->
No action, clock loss not detected.
1
0
X
Clock failure -->
CRG performs Clock Monitor Reset immediately
0
Clock failure -->
Scenario 1: OSCCLK recovers prior to exiting wait mode.
– MCU remains in wait mode,
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– Set SCMIF interrupt flag.
Some time later OSCCLK recovers.
– CM no longer indicates a failure,
– 4096 OSCCLK cycles later clock quality check indicates clock o.k.,
– SCM deactivated,
– PLL disabled depending on PLLWAI,
– VREG remains enabled (never gets disabled in wait mode).
– MCU remains in wait mode.
Some time later either a wakeup interrupt occurs (no SCM interrupt)
– Exit wait mode using OSCCLK as system clock (SYSCLK),
– Continue normal operation.
or an External Reset is applied.
– Exit wait mode using OSCCLK as system clock,
– Start reset sequence.
Scenario 2: OSCCLK does not recover prior to exiting wait mode.
– MCU remains in wait mode,
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– Set SCMIF interrupt flag,
– Keep performing clock quality checks (could continue infinitely) while in wait mode.
Some time later either a wakeup interrupt occurs (no SCM interrupt)
– Exit wait mode in SCM using PLL clock (fSCM) as system clock,
– Continue to perform additional clock quality checks until OSCCLK is o.k. again.
or an External RESET is applied.
– Exit wait mode in SCM using PLL clock (fSCM) as system clock,
– Start reset sequence,
– Continue to perform additional clock quality checks until OSCCLK is o.k.again.
1
Clock failure -->
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– SCMIF set.
SCMIF generates self clock mode wakeup interrupt.
– Exit wait mode in SCM using PLL clock (fSCM) as system clock,
– Continue to perform a additional clock quality checks until OSCCLK is o.k. again.
1
1
1
1
CRG Actions
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
359
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Core req’s
Stop Mode.
Clear PLLSEL,
Disable PLL
Exit Stop w.
ext.RESET
Stop Mode left
due to external reset
No
INT
?
Yes
No
Enter
Stop Mode
PSTP=1
?
Yes
CME=1
?
No
Yes
SCME=1 &
FSTWKP=1
?
No
INT
?
Yes
Yes
CM fail
?
No
No
Yes
No
Exit Stop w.
CMRESET
No
SCME=1
?
Yes
Clock
OK
?
Exit Stop w.
CMRESET
SCME=1
?
Yes
Yes
Exit
Stop Mode
Exit
Stop Mode
no
Exit
Stop Mode
SCMIE=1
?
Generate
SCM Interrupt
(Wakeup from Stop)
No
Exit
Stop Mode
Yes
Exit
Stop Mode
No
SCM=1
?
Yes
Enter
SCM
Enter SCM
SCMIF not
set!
Enter
SCM
Enter
SCM
Continue w.
normal OP
Figure 7-22. Stop Mode Entry/Exit Sequence
MC9S12XHZ512 Data Sheet, Rev. 1.06
360
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.4.3.3.1
Wake-up from Pseudo Stop Mode (PSTP=1)
Wake-up from pseudo stop mode is the same as wake-up from wait mode. There are also four different
scenarios for the CRG to restart the MCU from pseudo stop mode:
• External reset
• Clock monitor fail
• COP reset
• Wake-up interrupt
If the MCU gets an external reset or COP reset during pseudo stop mode active, the CRG asynchronously
restores all configuration bits in the register space to its default settings and starts the reset generator. After
completing the reset sequence processing begins by fetching the normal or COP reset vector. pseudo stop
mode is left and the MCU is in run mode again.
If the clock monitor is enabled (CME = 1), the MCU is able to leave pseudo stop mode when loss of
oscillator/external clock is detected by a clock monitor fail. If the SCME bit is not asserted the CRG
generates a clock monitor fail reset (CMRESET). The CRG’s behavior for CMRESET is the same
compared to external reset, but another reset vector is fetched after completion of the reset sequence. If the
SCME bit is asserted the CRG generates a SCM interrupt if enabled (SCMIE = 1). After generating the
interrupt the CRG enters self-clock mode and starts the clock quality checker (Section 7.4.1.4, “Clock
Quality Checker”). Then the MCU continues with normal operation. If the SCM interrupt is blocked by
SCMIE=0, the SCMIF flag will be asserted but the CRG will not wake-up from pseudo stop mode.
If any other interrupt source (e.g., RTI) triggers exit from pseudo stop mode, the MCU immediately
continues with normal operation. Because the PLL has been powered-down during stop mode, the
PLLSEL bit is cleared and the MCU runs on OSCCLK after leaving stop mode. The software must set the
PLLSEL bit again, in order to switch system and core clocks to the PLLCLK.
Table 7-13 summarizes the outcome of a clock loss while in pseudo stop mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
361
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-13. Outcome of Clock Loss in Pseudo Stop Mode
CME
SCME
SCMIE
0
X
X
Clock failure -->
No action, clock loss not detected.
1
0
X
Clock failure -->
CRG performs Clock Monitor Reset immediately
0
Clock Monitor failure -->
Scenario 1: OSCCLK recovers prior to exiting pseudo stop mode.
– MCU remains in pseudo stop mode,
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– Set SCMIF interrupt flag.
Some time later OSCCLK recovers.
– CM no longer indicates a failure,
– 4096 OSCCLK cycles later clock quality check indicates clock o.k.,
– SCM deactivated,
– PLL disabled,
– VREG disabled.
– MCU remains in pseudo stop mode.
Some time later either a wakeup interrupt occurs (no SCM interrupt)
– Exit pseudo stop mode using OSCCLK as system clock (SYSCLK),
– Continue normal operation.
or an External Reset is applied.
– Exit pseudo stop mode using OSCCLK as system clock,
– Start reset sequence.
Scenario 2: OSCCLK does not recover prior to exiting pseudo stop mode.
– MCU remains in pseudo stop mode,
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– Set SCMIF interrupt flag,
– Keep performing clock quality checks (could continue infinitely) while
in pseudo stop mode.
Some time later either a wakeup interrupt occurs (no SCM interrupt)
– Exit pseudo stop mode in SCM using PLL clock (fSCM) as system clock
– Continue to perform additional clock quality checks until OSCCLK is o.k. again.
or an External RESET is applied.
– Exit pseudo stop mode in SCM using PLL clock (fSCM) as system clock
– Start reset sequence,
– Continue to perform additional clock quality checks until OSCCLK is o.k.again.
1
Clock failure -->
– VREG enabled,
– PLL enabled,
– SCM activated,
– Start clock quality check,
– SCMIF set.
SCMIF generates self clock mode wakeup interrupt.
– Exit pseudo stop mode in SCM using PLL clock (fSCM) as system clock,
– Continue to perform a additional clock quality checks until OSCCLK is o.k. again.
1
1
1
1
CRG Actions
MC9S12XHZ512 Data Sheet, Rev. 1.06
362
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.4.3.3.2
Wake-up from Full Stop (PSTP = 0)
The MCU requires an external interrupt or an external reset in order to wake-up from stop-mode.
If the MCU gets an external reset during full stop mode active, the CRG asynchronously restores all
configuration bits in the register space to its default settings and will perform a maximum of 50 clock
check_windows (see Section 7.4.1.4, “Clock Quality Checker”). After completing the clock quality check
the CRG starts the reset generator. After completing the reset sequence processing begins by fetching the
normal reset vector. Full stop-mode is left and the MCU is in run mode again.
If the MCU is woken-up by an interrupt and the fast wake-up feature is disabled (FSTWKP = 0 or
SCME = 0), the CRG will also perform a maximum of 50 clock check_windows (see Section 7.4.1.4,
“Clock Quality Checker”). If the clock quality check is successful, the CRG will release all system and
core clocks and will continue with normal operation. If all clock checks within the Timeout-Window are
failing, the CRG will switch to self-clock mode or generate a clock monitor reset (CMRESET) depending
on the setting of the SCME bit.
If the MCU is woken-up by an interrupt and the fast wake-up feature is enabled (FSTWKP = 1 and
SCME = 1), the system will immediately resume operation in self-clock mode (see Section 7.4.1.4, “Clock
Quality Checker”). The SCMIF flag will not be set. The system will remain in self-clock mode with
oscillator disabled until FSTWKP bit is cleared. The clearing of FSTWKP will start the oscillator and the
clock quality check. If the clock quality check is successful, the CRG will switch all system clocks to
oscillator clock. The SCMIF flag will be set. See application examples in Figure 7-23 and Figure 7-24.
Because the PLL has been powered-down during stop-mode the PLLSEL bit is cleared and the MCU runs
on OSCCLK after leaving stop-mode. The software must manually set the PLLSEL bit again, in order to
switch system and core clocks to the PLLCLK.
NOTE
In full stop mode or self-clock mode caused by the fast wake-up feature, the
clock monitor and the oscillator are disabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
363
Chapter 7 Clocks and Reset Generator (S12CRGV6)
CPU resumes program execution immediately
Instruction
FSTWKP=1
SCME=1 STOP
IRQ Service STOP
IRQ Service
IRQ Service STOP
Interrupt
Interrupt
Interrupt
Power Saving
Oscillator Clock
Oscillator Disabled
PLL Clock
Core Clock
Self-Clock Mode
Figure 7-23. Fast Wake-up from Full Stop Mode: Example 1
.
CPU resumes program execution immediately
Instruction
FSTWKP=1 SCME=1 STOP
IRQ Service FSTWKP=0
SCMIE=1
Freq. Uncritical
Instructions
IRQ Interrupt
Freq. Critical
Instr. Possible
SCM Interrupt
Clock Quality Check
Oscillator Clock
Oscillator Disabled
OSC Startup
PLL Clock
Core Clock
Self-Clock Mode
Figure 7-24. Fast Wake-up from Full Stop Mode: Example 2
MC9S12XHZ512 Data Sheet, Rev. 1.06
364
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.5
Resets
This section describes how to reset the CRG, and how the CRG itself controls the reset of the MCU. It
explains all special reset requirements. Since the reset generator for the MCU is part of the CRG, this
section also describes all automatic actions that occur during or as a result of individual reset conditions.
The reset values of registers and signals are provided in Section 7.3, “Memory Map and Register
Definition”. All reset sources are listed in Table 7-14. Refer to MCU specification for related vector
addresses and priorities.
Table 7-14. Reset Summary
7.5.1
Reset Source
Local Enable
Power on Reset
None
Low Voltage Reset
None
External Reset
None
Illegal Address Reset
None
Clock Monitor Reset
PLLCTL (CME = 1, SCME = 0)
COP Watchdog Reset
COPCTL (CR[2:0] nonzero)
Description of Reset Operation
The reset sequence is initiated by any of the following events:
• Low level is detected at the RESET pin (external reset)
• Power on is detected
• Low voltage is detected
• Illegal Address Reset is detected (see S12XMMC Block Guide for details)
• COP watchdog times out
• Clock monitor failure is detected and self-clock mode was disabled (SCME=0)
Upon detection of any reset event, an internal circuit drives the RESET pin low for 128 SYSCLK cycles
(see Figure 7-25). Since entry into reset is asynchronous, it does not require a running SYSCLK. However,
the internal reset circuit of the CRG cannot sequence out of current reset condition without a running
SYSCLK. The number of 128 SYSCLK cycles might be increased by n = 3 to 6 additional SYSCLK cycles
depending on the internal synchronization latency. After 128 + n SYSCLK cycles the RESET pin is
released. The reset generator of the CRG waits for additional 64 SYSCLK cycles and then samples the
RESET pin to determine the originating source. Table 7-15 shows which vector will be fetched.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
365
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Table 7-15. Reset Vector Selection
Sampled RESET Pin
(64 cycles
after release)
Clock Monitor
Reset Pending
COP
Reset Pending
Vector Fetch
1
0
0
POR / LVR / Illegal Address Reset / External Reset
1
1
X
Clock Monitor Reset
1
0
1
COP Reset
0
X
X
POR / LVR / Illegal Address Reset / External Reset
with rise of RESET pin
NOTE
External circuitry connected to the RESET pin should not include a large
capacitance that would interfere with the ability of this signal to rise to a
valid logic 1 within 64 SYSCLK cycles after the low drive is released.
The internal reset of the MCU remains asserted while the reset generator completes the 192 SYSCLK long
reset sequence. The reset generator circuitry always makes sure the internal reset is deasserted
synchronously after completion of the 192 SYSCLK cycles. In case the RESET pin is externally driven
low for more than these 192 SYSCLK cycles (external reset), the internal reset remains asserted too.
RESET
)(
)(
CRG drives RESET pin low
RESET pin
released
)
)
SYSCLK
(
(
128 + n cycles
Possibly
SYSCLK
not
running
)
(
64 cycles
With n being
min 3 / max 6
cycles depending
on internal
synchronization
delay
Possibly
RESET
driven low
externally
Figure 7-25. RESET Timing
MC9S12XHZ512 Data Sheet, Rev. 1.06
366
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.5.2
Clock Monitor Reset
The CRG generates a clock monitor reset in case all of the following conditions are true:
• Clock monitor is enabled (CME = 1)
• Loss of clock is detected
• Self-clock mode is disabled (SCME = 0).
The reset event asynchronously forces the configuration registers to their default settings (see Section 7.3,
“Memory Map and Register Definition”). In detail the CME and the SCME are reset to logical ‘1’ (which
doesn’t change the state of the CME bit, because it has already been set). As a consequence the CRG
immediately enters self clock mode and starts its internal reset sequence. In parallel the clock quality check
starts. As soon as clock quality check indicates a valid oscillator clock the CRG switches to OSCCLK and
leaves self clock mode. Since the clock quality checker is running in parallel to the reset generator, the
CRG may leave self clock mode while still completing the internal reset sequence. When the reset
sequence is finished, the CRG checks the internally latched state of the clock monitor fail circuit. If a clock
monitor fail is indicated, processing begins by fetching the clock monitor reset vector.
7.5.3
Computer Operating Properly Watchdog (COP) Reset
When COP is enabled, the CRG expects sequential write of 0x_55 and 0x_AA (in this order) to the
ARMCOP register during the selected time-out period. Once this is done, the COP time-out period restarts.
If the program fails to do this the CRG will generate a reset. Also, if any value other than 0x_55 or 0x_AA
is written, the CRG immediately generates a reset. In case windowed COP operation is enabled writes
(0x_55 or 0x_AA) to the ARMCOP register must occur in the last 25% of the selected time-out period. A
premature write the CRG will immediately generate a reset.
As soon as the reset sequence is completed the reset generator checks the reset condition. If no clock
monitor failure is indicated and the latched state of the COP timeout is true, processing begins by fetching
the COP vector.
7.5.4
Power On Reset, Low Voltage Reset
The on-chip voltage regulator detects when VDD to the MCU has reached a certain level and asserts power
on reset or low voltage reset or both. As soon as a power on reset or low voltage reset is triggered the CRG
performs a quality check on the incoming clock signal. As soon as clock quality check indicates a valid
oscillator clock signal, the reset sequence starts using the oscillator clock. If after 50 check windows the
clock quality check indicated a non-valid oscillator clock, the reset sequence starts using self-clock mode.
Figure 7-26 and Figure 7-27 show the power-up sequence for cases when the RESET pin is tied to VDD
and when the RESET pin is held low.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
367
Chapter 7 Clocks and Reset Generator (S12CRGV6)
Clock Quality Check
(no Self-Clock Mode)
RESET
)(
Internal POR
)(
128 SYSCLK
Internal RESET
)(
64 SYSCLK
Figure 7-26. RESET Pin Tied to VDD (by a pull-up resistor)
Clock Quality Check
(no Self Clock Mode)
)(
RESET
Internal POR
)(
128 SYSCLK
Internal RESET
)(
64 SYSCLK
Figure 7-27. RESET Pin Held Low Externally
7.6
Interrupts
The interrupts/reset vectors requested by the CRG are listed in Table 7-16. Refer to MCU specification for
related vector addresses and priorities.
Table 7-16. CRG Interrupt Vectors
7.6.1
Interrupt Source
CCR
Mask
Local Enable
Real time interrupt
I bit
CRGINT (RTIE)
LOCK interrupt
I bit
CRGINT (LOCKIE)
SCM interrupt
I bit
CRGINT (SCMIE)
Real Time Interrupt
The CRG generates a real time interrupt when the selected interrupt time period elapses. RTI interrupts are
locally disabled by setting the RTIE bit to 0. The real time interrupt flag (RTIF) is set to1 when a timeout
occurs, and is cleared to 0 by writing a 1 to the RTIF bit.
The RTI continues to run during pseudo stop mode if the PRE bit is set to 1. This feature can be used for
periodic wakeup from pseudo stop if the RTI interrupt is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
368
Freescale Semiconductor
Chapter 7 Clocks and Reset Generator (S12CRGV6)
7.6.2
PLL Lock Interrupt
The CRG generates a PLL Lock interrupt when the LOCK condition of the PLL has changed, either from
a locked state to an unlocked state or vice versa. Lock interrupts are locally disabled by setting the
LOCKIE bit to 0. The PLL Lock interrupt flag (LOCKIF) is set to1 when the LOCK condition has
changed, and is cleared to 0 by writing a 1 to the LOCKIF bit.
7.6.3
Self Clock Mode Interrupt
The CRG generates a self clock mode interrupt when the SCM condition of the system has changed, either
entered or exited self clock mode. SCM conditions can only change if the self clock mode enable bit
(SCME) is set to 1. SCM conditions are caused by a failing clock quality check after power on reset (POR)
or low voltage reset (LVR) or recovery from full stop mode (PSTP = 0) or clock monitor failure. For details
on the clock quality check refer to Section 7.4.1.4, “Clock Quality Checker”. If the clock monitor is
enabled (CME = 1) a loss of external clock will also cause a SCM condition (SCME = 1).
SCM interrupts are locally disabled by setting the SCMIE bit to 0. The SCM interrupt flag (SCMIF) is set
to1 when the SCM condition has changed, and is cleared to 0 by writing a 1 to the SCMIF bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
369
Chapter 7 Clocks and Reset Generator (S12CRGV6)
MC9S12XHZ512 Data Sheet, Rev. 1.06
370
Freescale Semiconductor
Chapter 8
Pierce Oscillator (S12XOSCLCPV1)
8.1
Introduction
The Pierce oscillator (XOSC) module provides a robust, low-noise and low-power clock source. The
module will be operated from the VDDPLL supply rail (2.5 V nominal) and require the minimum number
of external components. It is designed for optimal start-up margin with typical crystal oscillators.
8.1.1
Features
The XOSC will contain circuitry to dynamically control current gain in the output amplitude. This ensures
a signal with low harmonic distortion, low power and good noise immunity.
• High noise immunity due to input hysteresis
• Low RF emissions with peak-to-peak swing limited dynamically
• Transconductance (gm) sized for optimum start-up margin for typical oscillators
• Dynamic gain control eliminates the need for external current limiting resistor
• Integrated resistor eliminates the need for external bias resistor
• Low power consumption:
— Operates from 2.5 V (nominal) supply
— Amplitude control limits power
• Clock monitor
8.1.2
Modes of Operation
Two modes of operation exist:
1. Loop controlled Pierce oscillator
2. External square wave mode featuring also full swing Pierce without internal feedback resistor
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
371
Chapter 8 Pierce Oscillator (S12XOSCLCPV1)
8.1.3
Block Diagram
Figure 8-1 shows a block diagram of the XOSC.
Monitor_Failure
Clock
Monitor
OSCCLK
Peak
Detector
Gain Control
VDDPLL = 2.5 V
Rf
XTAL
EXTAL
Figure 8-1. XOSC Block Diagram
8.2
External Signal Description
This section lists and describes the signals that connect off chip
8.2.1
VDDPLL and VSSPLL — Operating and Ground Voltage Pins
Theses pins provides operating voltage (VDDPLL) and ground (VSSPLL) for the XOSC circuitry. This
allows the supply voltage to the XOSC to be independently bypassed.
8.2.2
EXTAL and XTAL — Input and Output Pins
These pins provide the interface for either a crystal or a CMOS compatible clock to control the internal
clock generator circuitry. EXTAL is the external clock input or the input to the crystal oscillator amplifier.
XTAL is the output of the crystal oscillator amplifier. The MCU internal system clock is derived from the
MC9S12XHZ512 Data Sheet, Rev. 1.06
372
Freescale Semiconductor
Chapter 8 Pierce Oscillator (S12XOSCLCPV1)
EXTAL input frequency. In full stop mode (PSTP = 0), the EXTAL pin is pulled down by an internal
resistor of typical 200 kΩ.
NOTE
Freescale recommends an evaluation of the application board and chosen
resonator or crystal by the resonator or crystal supplier.
Loop controlled circuit is not suited for overtone resonators and crystals.
EXTAL
C1
MCU
Crystal or
Ceramic Resonator
XTAL
C2
VSSPLL
Figure 8-2. Loop Controlled Pierce Oscillator Connections (XCLKS = 0)
NOTE
Full swing Pierce circuit is not suited for overtone resonators and crystals
without a careful component selection.
EXTAL
C1
MCU
RB
Crystal or
Ceramic Resonator
RS*
XTAL
C2
VSSPLL
* Rs can be zero (shorted) when use with higher frequency crystals.
Refer to manufacturer’s data.
Figure 8-3. Full Swing Pierce Oscillator Connections (XCLKS = 1)
EXTAL
CMOS Compatible
External Oscillator
(VDDPLL Level)
MCU
XTAL
Not Connected
Figure 8-4. External Clock Connections (XCLKS = 1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
373
Chapter 8 Pierce Oscillator (S12XOSCLCPV1)
8.2.3
XCLKS — Input Signal
The XCLKS is an input signal which controls whether a crystal in combination with the internal loop
controlled (low power) Pierce oscillator is used or whether full swing Pierce oscillator/external clock
circuitry is used. Refer to the Device Overview chapter for polarity and sampling conditions of the XCLKS
pin. Table 8-1 lists the state coding of the sampled XCLKS signal.
.
Table 8-1. Clock Selection Based on XCLKS
XCLKS
8.3
Description
0
Loop controlled Pierce oscillator selected
1
Full swing Pierce oscillator/external clock selected
Memory Map and Register Definition
The CRG contains the registers and associated bits for controlling and monitoring the oscillator module.
8.4
Functional Description
The XOSC module has control circuitry to maintain the crystal oscillator circuit voltage level to an optimal
level which is determined by the amount of hysteresis being used and the maximum oscillation range.
The oscillator block has two external pins, EXTAL and XTAL. The oscillator input pin, EXTAL, is
intended to be connected to either a crystal or an external clock source. The selection of loop controlled
Pierce oscillator or full swing Pierce oscillator/external clock depends on the XCLKS signal which is
sampled during reset. The XTAL pin is an output signal that provides crystal circuit feedback.
A buffered EXTAL signal becomes the internal clock. To improve noise immunity, the oscillator is
powered by the VDDPLL and VSSPLL power supply pins.
8.4.1
Gain Control
A closed loop control system will be utilized whereby the amplifier is modulated to keep the output
waveform sinusoidal and to limit the oscillation amplitude. The output peak to peak voltage will be kept
above twice the maximum hysteresis level of the input buffer. Electrical specification details are provided
in the Electrical Characteristics appendix.
8.4.2
Clock Monitor
The clock monitor circuit is based on an internal RC time delay so that it can operate without any MCU
clocks. If no OSCCLK edges are detected within this RC time delay, the clock monitor indicates failure
which asserts self-clock mode or generates a system reset depending on the state of SCME bit. If the clock
monitor is disabled or the presence of clocks is detected no failure is indicated.The clock monitor function
is enabled/disabled by the CME control bit, described in the CRG block description chapter.
MC9S12XHZ512 Data Sheet, Rev. 1.06
374
Freescale Semiconductor
Chapter 8 Pierce Oscillator (S12XOSCLCPV1)
8.4.3
Wait Mode Operation
During wait mode, XOSC is not impacted.
8.4.4
Stop Mode Operation
XOSC is placed in a static state when the part is in stop mode except when pseudo-stop mode is enabled.
During pseudo-stop mode, XOSC is not impacted.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
375
Chapter 8 Pierce Oscillator (S12XOSCLCPV1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
376
Freescale Semiconductor
Chapter 9
Analog-to-Digital Converter (ATD10B16CV4)
Block Description
9.1
Introduction
The ATD10B16C is a 16-channel, 10-bit, multiplexed input successive approximation analog-to-digital
converter. Refer to the Electrical Specifications chapter for ATD accuracy.
9.1.1
•
•
•
•
•
•
•
•
•
•
•
•
•
•
9.1.2
Features
8-/10-bit resolution
7 µs, 10-bit single conversion time
Sample buffer amplifier
Programmable sample time
Left/right justified, signed/unsigned result data
External trigger control
Conversion completion interrupt generation
Analog input multiplexer for 16 analog input channels
Analog/digital input pin multiplexing
1 to 16 conversion sequence lengths
Continuous conversion mode
Multiple channel scans
Configurable external trigger functionality on any AD channel or any of four additional trigger
inputs. The four additional trigger inputs can be chip external or internal. Refer to device
specification for availability and connectivity
Configurable location for channel wrap around (when converting multiple channels in a sequence)
Modes of Operation
There is software programmable selection between performing single or continuous conversion on a
single channel or multiple channels.
9.1.3
Block Diagram
Refer to Figure 9-1 for a block diagram of the ATD0B16C block.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
377
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Bus Clock
ATD clock
Clock
Prescaler
Trigger
Mux
ETRIG0
ETRIG1
ETRIG2
ATD10B16C
Sequence Complete
Mode and
Timing Control
Interrupt
ETRIG3
(see Device Overview
chapter for availability
and connectivity)
ATDCTL1
ATDDIEN
Results
ATD 0
ATD 1
ATD 2
ATD 3
ATD 4
ATD 5
ATD 6
ATD 7
ATD 8
ATD 9
ATD 10
ATD 11
ATD 12
ATD 13
ATD 14
ATD 15
PORTAD
VDDA
VSSA
Successive
Approximation
Register (SAR)
and DAC
VRH
VRL
AN15
AN14
AN13
AN12
AN11
+
AN10
Sample & Hold
AN9
1
1
AN8
AN7
Analog
MUX
Comparator
AN6
AN5
AN4
AN3
AN2
AN1
AN0
Figure 9-1. ATD10B16C Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
378
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.2
External Signal Description
This section lists all inputs to the ATD10B16C block.
9.2.1
ANx (x = 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) — Analog Input
Channel x Pins
This pin serves as the analog input channel x. It can also be configured as general-purpose digital input
and/or external trigger for the ATD conversion.
9.2.2
ETRIG3, ETRIG2, ETRIG1, ETRIG0 — External Trigger Pins
These inputs can be configured to serve as an external trigger for the ATD conversion.
Refer to the Device Overview chapter for availability and connectivity of these inputs.
9.2.3
VRH, VRL — High Reference Voltage Pin, Low Reference Voltage Pin
VRH is the high reference voltage, VRL is the low reference voltage for ATD conversion.
9.2.4
VDDA, VSSA — Analog Circuitry Power Supply Pins
These pins are the power supplies for the analog circuitry of the ATD10B16CV4 block.
9.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the ATD10B16C.
9.3.1
Module Memory Map
Table 9-1 gives an overview of all ATD10B16C registers
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
379
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
.
Table 9-1. ATD10B16CV4 Memory Map
Address Offset
Use
Access
0x0000
ATD Control Register 0 (ATDCTL0)
R/W
0x0001
ATD Control Register 1 (ATDCTL1)
R/W
0x0002
ATD Control Register 2 (ATDCTL2)
R/W
0x0003
ATD Control Register 3 (ATDCTL3)
R/W
0x0004
ATD Control Register 4 (ATDCTL4)
R/W
0x0005
ATD Control Register 5 (ATDCTL5)
R/W
0x0006
ATD Status Register 0 (ATDSTAT0)
R/W
0x0007
Unimplemented
0x0008
ATD Test Register 0 (ATDTEST0)(1)
R
0x0009
ATD Test Register 1 (ATDTEST1)
R/W
0x000A
ATD Status Register 2 (ATDSTAT2)
R
0x000B
ATD Status Register 1 (ATDSTAT1)
R
0x000C
ATD Input Enable Register 0 (ATDDIEN0)
R/W
0x000D
ATD Input Enable Register 1 (ATDDIEN1)
R/W
0x000E
Port Data Register 0 (PORTAD0)
R
0x000F
Port Data Register 1 (PORTAD1)
R
0x0010, 0x0011
ATD Result Register 0 (ATDDR0H, ATDDR0L)
R/W
0x0012, 0x0013
ATD Result Register 1 (ATDDR1H, ATDDR1L)
R/W
0x0014, 0x0015
ATD Result Register 2 (ATDDR2H, ATDDR2L)
R/W
0x0016, 0x0017
ATD Result Register 3 (ATDDR3H, ATDDR3L)
R/W
0x0018, 0x0019
ATD Result Register 4 (ATDDR4H, ATDDR4L)
R/W
0x001A, 0x001B
ATD Result Register 5 (ATDDR5H, ATDDR5L)
R/W
0x001C, 0x001D
ATD Result Register 6 (ATDDR6H, ATDDR6L)
R/W
0x001E, 0x001F
ATD Result Register 7 (ATDDR7H, ATDDR7L)
R/W
0x0020, 0x0021
ATD Result Register 8 (ATDDR8H, ATDDR8L)
R/W
0x0022, 0x0023
ATD Result Register 9 (ATDDR9H, ATDDR9L)
R/W
0x0024, 0x0025
ATD Result Register 10 (ATDDR10H, ATDDR10L)
R/W
0x0026, 0x0027
ATD Result Register 11 (ATDDR11H, ATDDR11L)
R/W
0x0028, 0x0029
ATD Result Register 12 (ATDDR12H, ATDDR12L)
R/W
0x002A, 0x002B
ATD Result Register 13 (ATDDR13H, ATDDR13L)
R/W
0x002C, 0x002D
ATD Result Register 14 (ATDDR14H, ATDDR14L)
R/W
0x002E, 0x002F
ATD Result Register 15 (ATDDR15H, ATDDR15L)
1. ATDTEST0 is intended for factory test purposes only.
R/W
NOTE
Register Address = Base Address + Address Offset, where the Base Address
is defined at the MCU level and the Address Offset is defined at the module
level.
MC9S12XHZ512 Data Sheet, Rev. 1.06
380
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2
Register Descriptions
This section describes in address order all the ATD10B16C registers and their individual bits.
Register
Name
0x0000
ATDCTL0
0x0001
ATDCTL1
0x0002
ATDCTL2
R
R
W
W
0x0004
ATDCTL4
W
R
R
R
W
0x0006
ATDSTAT0
W
0x0007
Unimplemented
W
R
0
0
0
0
0
0
0
AFFC
AWAI
ETRIGLE
ETRIGP
ETRIGE
ASCIE
S8C
S4C
S2C
S1C
FIFO
FRZ1
FRZ0
SRES8
SMP1
SMP0
PRS4
PRS3
PRS2
PRS1
PRS0
DJM
DSGN
SCAN
MULT
CD
CC
CB
CA
ETORF
FIFOR
CC3
CC2
CC1
CC0
ADPU
0
SCF
0
R
3
2
1
Bit 0
WRAP3
WRAP2
WRAP1
WRAP0
ETRIGCH3 ETRIGCH2 ETRIGCH1 ETRIGCH0
ASCIF
Unimplemented
W
W
0x000A
ATDSTAT2
W
0x000C
ATDDIEN0
4
R
0x0009
ATDTEST1
0x000B
ATDSTAT1
5
ETRIGSEL
R
W
0x0008
ATDTEST0
6
W
0x0003
ATDCTL3
0x0005
ATDCTL5
Bit 7
R
R
R
Unimplemented
SC
CCF15
CCF14
CCF13
CCF12
CCF11
CCF10
CCF9
CCF8
CCF7
CCF6
CCF5
CCF4
CCF3
CCF2
CCF1
CCF0
IEN15
IEN14
IEN13
IEN12
IEN11
IEN10
IEN9
IEN8
W
R
W
= Unimplemented or Reserved
u = Unaffected
Figure 9-2. ATD Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
381
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Register
Name
0x000D
ATDDIEN1
R
W
0x000E
PORTAD0
R
Bit 7
6
5
4
3
2
1
Bit 0
IEN7
IEN6
IEN5
IEN4
IEN3
IEN2
IEN1
IEN0
PTAD15
PTAD14
PTAD13
PTAD12
PTAD11
PTAD10
PTAD9
PTAD8
PTAD7
PTAD6
PTAD5
PTAD4
PTAD3
PTAD2
PTAD1
PTAD0
BIT 8
BIT 6
BIT 7
BIT 5
BIT 6
BIT 4
BIT 5
BIT 3
BIT 4
BIT 2
BIT 3
BIT 1
BIT 2
BIT 0
BIT 0
u
0
0
0
0
0
0
0
0
0
0
0
0
W
0x000F
PORTAD1
R
W
R BIT 9 MSB
BIT 7 MSB
0x0010–0x002F W
ATDDRxH–
ATDDRxL R
BIT 1
u
W
= Unimplemented or Reserved
u = Unaffected
Figure 9-2. ATD Register Summary (continued)
9.3.2.1
ATD Control Register 0 (ATDCTL0)
Writes to this register will abort current conversion sequence but will not start a new sequence.
Module Base + 0x0000
R
7
6
5
4
0
0
0
0
3
2
1
0
WRAP3
WRAP2
WRAP1
WRAP0
1
1
1
1
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 9-3. ATD Control Register 0 (ATDCTL0)
Read: Anytime
Write: Anytime
Table 9-2. ATDCTL0 Field Descriptions
Field
3:0
WRAP[3:0]
Description
Wrap Around Channel Select Bits — These bits determine the channel for wrap around when doing multichannel conversions. The coding is summarized in Table 9-3.
MC9S12XHZ512 Data Sheet, Rev. 1.06
382
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-3. Multi-Channel Wrap Around Coding
9.3.2.2
WRAP3
WRAP2
WRAP1
WRAP0
Multiple Channel Conversions
(MULT = 1) Wrap Around to AN0
after Converting
0
0
0
0
Reserved
0
0
0
1
AN1
0
0
1
0
AN2
0
0
1
1
AN3
0
1
0
0
AN4
0
1
0
1
AN5
0
1
1
0
AN6
0
1
1
1
AN7
1
0
0
0
AN8
1
0
0
1
AN9
1
0
1
0
AN10
1
0
1
1
AN11
1
1
0
0
AN12
1
1
0
1
AN13
1
1
1
0
AN14
1
1
1
1
AN15
ATD Control Register 1 (ATDCTL1)
Writes to this register will abort current conversion sequence but will not start a new sequence.
Module Base + 0x0001
7
R
6
5
4
0
0
0
ETRIGSEL
3
2
1
0
ETRIGCH3
ETRIGCH2
ETRIGCH1
ETRIGCH0
1
1
1
1
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 9-4. ATD Control Register 1 (ATDCTL1)
Read: Anytime
Write: Anytime
Table 9-4. ATDCTL1 Field Descriptions
Field
Description
7
ETRIGSEL
External Trigger Source Select — This bit selects the external trigger source to be either one of the AD
channels or one of the ETRIG[3:0] inputs. See device specification for availability and connectivity of
ETRIG[3:0] inputs. If ETRIG[3:0] input option is not available, writing a 1 to ETRISEL only sets the bit but has
no effect, that means one of the AD channels (selected by ETRIGCH[3:0]) remains the source for external
trigger. The coding is summarized in Table 9-5.
3:0
External Trigger Channel Select — These bits select one of the AD channels or one of the ETRIG[3:0] inputs
ETRIGCH[3:0] as source for the external trigger. The coding is summarized in Table 9-5.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
383
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-5. External Trigger Channel Select Coding
ETRIGSEL
ETRIGCH3
ETRIGCH2
ETRIGCH1
ETRIGCH0
External Trigger Source
0
0
0
0
0
AN0
0
0
0
0
1
AN1
0
0
0
1
0
AN2
0
0
0
1
1
AN3
0
0
1
0
0
AN4
0
0
1
0
1
AN5
0
0
1
1
0
AN6
0
0
1
1
1
AN7
0
1
0
0
0
AN8
0
1
0
0
1
AN9
0
1
0
1
0
AN10
0
1
0
1
1
AN11
0
1
1
0
0
AN12
0
1
1
0
1
AN13
0
1
1
1
0
AN14
0
1
1
1
1
AN15
1
0
0
0
0
ETRIG0(1)
1
0
0
0
1
ETRIG11
1
0
0
1
0
ETRIG21
1
0
0
1
1
ETRIG31
1
0
1
X
X
Reserved
1
1
X
X
X
Reserved
1. Only if ETRIG[3:0] input option is available (see device specification), else ETRISEL is ignored, that means
external trigger source remains on one of the AD channels selected by ETRIGCH[3:0]
9.3.2.3
ATD Control Register 2 (ATDCTL2)
This register controls power down, interrupt and external trigger. Writes to this register will abort current
conversion sequence but will not start a new sequence.
MC9S12XHZ512 Data Sheet, Rev. 1.06
384
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Module Base + 0x0002
7
6
5
4
3
2
1
ADPU
AFFC
AWAI
ETRIGLE
ETRIGP
ETRIGE
ASCIE
0
0
0
0
0
0
0
R
0
ASCIF
W
Reset
0
= Unimplemented or Reserved
Figure 9-5. ATD Control Register 2 (ATDCTL2)
Read: Anytime
Write: Anytime
Table 9-6. ATDCTL2 Field Descriptions
Field
Description
7
ADPU
ATD Power Down — This bit provides on/off control over the ATD10B16C block allowing reduced MCU power
consumption. Because analog electronic is turned off when powered down, the ATD requires a recovery time
period after ADPU bit is enabled.
0 Power down ATD
1 Normal ATD functionality
6
AFFC
ATD Fast Flag Clear All
0 ATD flag clearing operates normally (read the status register ATDSTAT1 before reading the result register
to clear the associate CCF flag).
1 Changes all ATD conversion complete flags to a fast clear sequence. Any access to a result register will
cause the associate CCF flag to clear automatically.
5
AWAI
ATD Power Down in Wait Mode — When entering Wait Mode this bit provides on/off control over the
ATD10B16C block allowing reduced MCU power. Because analog electronic is turned off when powered down,
the ATD requires a recovery time period after exit from Wait mode.
0 ATD continues to run in Wait mode
1 Halt conversion and power down ATD during Wait mode
After exiting Wait mode with an interrupt conversion will resume. But due to the recovery time the result of
this conversion should be ignored.
4
ETRIGLE
External Trigger Level/Edge Control — This bit controls the sensitivity of the external trigger signal. See
Table 9-7 for details.
3
ETRIGP
External Trigger Polarity — This bit controls the polarity of the external trigger signal. See Table 9-7 for
details.
2
ETRIGE
External Trigger Mode Enable — This bit enables the external trigger on one of the AD channels or one of
the ETRIG[3:0] inputs as described in Table 9-5. If external trigger source is one of the AD channels, the digital
input buffer of this channel is enabled. The external trigger allows to synchronize the start of conversion with
external events.
0 Disable external trigger
1 Enable external trigger
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
385
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-6. ATDCTL2 Field Descriptions (continued)
Field
Description
1
ASCIE
ATD Sequence Complete Interrupt Enable
0 ATD Sequence Complete interrupt requests are disabled.
1 ATD Interrupt will be requested whenever ASCIF = 1 is set.
0
ASCIF
ATD Sequence Complete Interrupt Flag — If ASCIE = 1 the ASCIF flag equals the SCF flag (see
Section 9.3.2.7, “ATD Status Register 0 (ATDSTAT0)”), else ASCIF reads zero. Writes have no effect.
0 No ATD interrupt occurred
1 ATD sequence complete interrupt pending
Table 9-7. External Trigger Configurations
ETRIGLE
ETRIGP
External Trigger Sensitivity
0
0
Falling Edge
0
1
Ring Edge
1
0
Low Level
1
1
High Level
MC9S12XHZ512 Data Sheet, Rev. 1.06
386
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.4
ATD Control Register 3 (ATDCTL3)
This register controls the conversion sequence length, FIFO for results registers and behavior in Freeze
Mode. Writes to this register will abort current conversion sequence but will not start a new sequence.
Module Base + 0x0003
7
R
6
5
4
3
2
1
0
S8C
S4C
S2C
S1C
FIFO
FRZ1
FRZ0
0
1
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 9-6. ATD Control Register 3 (ATDCTL3)
Read: Anytime
Write: Anytime
Table 9-8. ATDCTL3 Field Descriptions
Field
Description
6
S8C
Conversion Sequence Length — This bit controls the number of conversions per sequence. Table 9-9 shows
all combinations. At reset, S4C is set to 1 (sequence length is 4). This is to maintain software continuity to HC12
Family.
5
S4C
Conversion Sequence Length — This bit controls the number of conversions per sequence. Table 9-9 shows
all combinations. At reset, S4C is set to 1 (sequence length is 4). This is to maintain software continuity to HC12
Family.
4
S2C
Conversion Sequence Length — This bit controls the number of conversions per sequence. Table 9-9 shows
all combinations. At reset, S4C is set to 1 (sequence length is 4). This is to maintain software continuity to HC12
Family.
3
S1C
Conversion Sequence Length — This bit controls the number of conversions per sequence. Table 9-9 shows
all combinations. At reset, S4C is set to 1 (sequence length is 4). This is to maintain software continuity to HC12
Family.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
387
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-8. ATDCTL3 Field Descriptions (continued)
Field
Description
2
FIFO
Result Register FIFO Mode —If this bit is zero (non-FIFO mode), the A/D conversion results map into the
result registers based on the conversion sequence; the result of the first conversion appears in the first result
register, the second result in the second result register, and so on.
If this bit is one (FIFO mode) the conversion counter is not reset at the beginning or ending of a conversion
sequence; sequential conversion results are placed in consecutive result registers. In a continuously scanning
conversion sequence, the result register counter will wrap around when it reaches the end of the result register
file. The conversion counter value (CC3-0 in ATDSTAT0) can be used to determine where in the result register
file, the current conversion result will be placed.
Aborting a conversion or starting a new conversion by write to an ATDCTL register (ATDCTL5-0) clears the
conversion counter even if FIFO=1. So the first result of a new conversion sequence, started by writing to
ATDCTL5, will always be place in the first result register (ATDDDR0). Intended usage of FIFO mode is
continuos conversion (SCAN=1) or triggered conversion (ETRIG=1).
Finally, which result registers hold valid data can be tracked using the conversion complete flags. Fast flag clear
mode may or may not be useful in a particular application to track valid data.
0 Conversion results are placed in the corresponding result register up to the selected sequence length.
1 Conversion results are placed in consecutive result registers (wrap around at end).
1:0
FRZ[1:0]
Background Debug Freeze Enable — When debugging an application, it is useful in many cases to have the
ATD pause when a breakpoint (Freeze Mode) is encountered. These 2 bits determine how the ATD will respond
to a breakpoint as shown in Table 9-10. Leakage onto the storage node and comparator reference capacitors
may compromise the accuracy of an immediately frozen conversion depending on the length of the freeze
period.
Table 9-9. Conversion Sequence Length Coding
S8C
S4C
S2C
S1C
Number of Conversions
per Sequence
0
0
0
0
16
0
0
0
1
1
0
0
1
0
2
0
0
1
1
3
0
1
0
0
4
0
1
0
1
5
0
1
1
0
6
0
1
1
1
7
1
0
0
0
8
1
0
0
1
9
1
0
1
0
10
1
0
1
1
11
1
1
0
0
12
1
1
0
1
13
1
1
1
0
14
1
1
1
1
15
MC9S12XHZ512 Data Sheet, Rev. 1.06
388
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-10. ATD Behavior in Freeze Mode (Breakpoint)
FRZ1
FRZ0
Behavior in Freeze Mode
0
0
Continue conversion
0
1
Reserved
1
0
Finish current conversion, then freeze
1
1
Freeze Immediately
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
389
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.5
ATD Control Register 4 (ATDCTL4)
This register selects the conversion clock frequency, the length of the second phase of the sample time and
the resolution of the A/D conversion (i.e., 8-bits or 10-bits). Writes to this register will abort current
conversion sequence but will not start a new sequence.
Module Base + 0x0004
7
6
5
4
3
2
1
0
SRES8
SMP1
SMP0
PRS4
PRS3
PRS2
PRS1
PRS0
0
0
0
0
0
1
0
1
R
W
Reset
Figure 9-7. ATD Control Register 4 (ATDCTL4)
Read: Anytime
Write: Anytime
Table 9-11. ATDCTL4 Field Descriptions
Field
Description
7
SRES8
A/D Resolution Select — This bit selects the resolution of A/D conversion results as either 8 or 10 bits. The
A/D converter has an accuracy of 10 bits. However, if low resolution is required, the conversion can be speeded
up by selecting 8-bit resolution.
0 10 bit resolution
1 8 bit resolution
6:5
SMP[1:0]
Sample Time Select —These two bits select the length of the second phase of the sample time in units of ATD
conversion clock cycles. Note that the ATD conversion clock period is itself a function of the prescaler value
(bits PRS4-0). The sample time consists of two phases. The first phase is two ATD conversion clock cycles
long and transfers the sample quickly (via the buffer amplifier) onto the A/D machine’s storage node. The
second phase attaches the external analog signal directly to the storage node for final charging and high
accuracy. Table 9-12 lists the lengths available for the second sample phase.
4:0
PRS[4:0]
ATD Clock Prescaler — These 5 bits are the binary value prescaler value PRS. The ATD conversion clock
frequency is calculated as follows:
[ BusClock ]
ATDclock = -------------------------------- × 0.5
[ PRS + 1 ]
Note: The maximum ATD conversion clock frequency is half the bus clock. The default (after reset) prescaler
value is 5 which results in a default ATD conversion clock frequency that is bus clock divided by 12.
Table 9-13 illustrates the divide-by operation and the appropriate range of the bus clock.
Table 9-12. Sample Time Select
SMP1
SMP0
Length of 2nd Phase of Sample Time
0
0
2 A/D conversion clock periods
0
1
4 A/D conversion clock periods
1
0
8 A/D conversion clock periods
1
1
16 A/D conversion clock periods
MC9S12XHZ512 Data Sheet, Rev. 1.06
390
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-13. Clock Prescaler Values
Prescale Value
Total Divisor
Value
Max. Bus Clock(1)
Min. Bus Clock(2)
1 MHz
00000
4 MHz
Divide by 2
2 MHz
00001
8 MHz
Divide by 4
3 MHz
00010
12 MHz
Divide by 6
4 MHz
00011
16 MHz
Divide by 8
5 MHz
00100
20 MHz
Divide by 10
6 MHz
00101
24 MHz
Divide by 12
7 MHz
00110
28 MHz
Divide by 14
8 MHz
00111
32 MHz
Divide by 16
9 MHz
36 MHz
01000
Divide by 18
10 MHz
40 MHz
01001
Divide by 20
11 MHz
44 MHz
01010
Divide by 22
12 MHz
48 MHz
01011
Divide by 24
13 MHz
52 MHz
01100
Divide by 26
14 MHz
56 MHz
01101
Divide by 28
15 MHz
60 MHz
01110
Divide by 30
16 MHz
64 MHz
01111
Divide by 32
17 MHz
68 MHz
10000
Divide by 34
18 MHz
72 MHz
10001
Divide by 36
19 MHz
76 MHz
10010
Divide by 38
20 MHz
80 MHz
10011
Divide by 40
21 MHz
84 MHz
10100
Divide by 42
22 MHz
88 MHz
Divide by 44
10101
23 MHz
92 MHz
Divide by 46
10110
24 MHz
96 MHz
Divide by 48
10111
25 MHz
100 MHz
Divide by 50
11000
26 MHz
104 MHz
Divide by 52
11001
27 MHz
108 MHz
Divide by 54
11010
28 MHz
112 MHz
Divide by 56
11011
29 MHz
116 MHz
Divide by 58
11100
30 MHz
120 MHz
Divide by 60
11101
31 MHz
124 MHz
Divide by 62
11110
32 MHz
128 MHz
Divide by 64
11111
1. Maximum ATD conversion clock frequency is 2 MHz. The maximum allowed bus clock frequency is
shown in this column.
2. Minimum ATD conversion clock frequency is 500 kHz. The minimum allowed bus clock frequency is
shown in this column.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
391
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.6
ATD Control Register 5 (ATDCTL5)
This register selects the type of conversion sequence and the analog input channels sampled. Writes to this
register will abort current conversion sequence and start a new conversion sequence. If external trigger is
enabled (ETRIGE = 1) an initial write to ATDCTL5 is required to allow starting of a conversion sequence
which will then occur on each trigger event. Start of conversion means the beginning of the sampling
phase.
Module Base + 0x0005
7
6
5
4
3
2
1
0
DJM
DSGN
SCAN
MULT
CD
CC
CB
CA
0
0
0
0
0
0
0
0
R
W
Reset
Figure 9-8. ATD Control Register 5 (ATDCTL5)
Read: Anytime
Write: Anytime
Table 9-14. ATDCTL5 Field Descriptions
Field
Description
7
DJM
Result Register Data Justification — This bit controls justification of conversion data in the result registers.
See Section 9.3.2.16, “ATD Conversion Result Registers (ATDDRx)” for details.
0 Left justified data in the result registers.
1 Right justified data in the result registers.
6
DSGN
Result Register Data Signed or Unsigned Representation — This bit selects between signed and unsigned
conversion data representation in the result registers. Signed data is represented as 2’s complement. Signed
data is not available in right justification. See <st-bold>9.3.2.16 ATD Conversion Result Registers (ATDDRx)
for details.
0 Unsigned data representation in the result registers.
1 Signed data representation in the result registers.
Table 9-15 summarizes the result data formats available and how they are set up using the control bits.
Table 9-16 illustrates the difference between the signed and unsigned, left justified output codes for an input
signal range between 0 and 5.12 Volts.
5
SCAN
Continuous Conversion Sequence Mode — This bit selects whether conversion sequences are performed
continuously or only once. If external trigger is enabled (ETRIGE=1) setting this bit has no effect, that means
each trigger event starts a single conversion sequence.
0 Single conversion sequence
1 Continuous conversion sequences (scan mode)
4
MULT
Multi-Channel Sample Mode — When MULT is 0, the ATD sequence controller samples only from the
specified analog input channel for an entire conversion sequence. The analog channel is selected by channel
selection code (control bits CD/CC/CB/CA located in ATDCTL5). When MULT is 1, the ATD sequence controller
samples across channels. The number of channels sampled is determined by the sequence length value (S8C,
S4C, S2C, S1C). The first analog channel examined is determined by channel selection code (CC, CB, CA
control bits); subsequent channels sampled in the sequence are determined by incrementing the channel
selection code or wrapping around to AN0 (channel 0.
0 Sample only one channel
1 Sample across several channels
MC9S12XHZ512 Data Sheet, Rev. 1.06
392
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-14. ATDCTL5 Field Descriptions (continued)
Field
Description
3:0
C[D:A}
Analog Input Channel Select Code — These bits select the analog input channel(s) whose signals are
sampled and converted to digital codes. Table 9-17 lists the coding used to select the various analog input
channels.
In the case of single channel conversions (MULT = 0), this selection code specified the channel to be examined.
In the case of multiple channel conversions (MULT = 1), this selection code represents the first channel to be
examined in the conversion sequence. Subsequent channels are determined by incrementing the channel
selection code or wrapping around to AN0 (after converting the channel defined by the Wrap Around Channel
Select Bits WRAP[3:0] in ATDCTL0). In case starting with a channel number higher than the one defined by
WRAP[3:0] the first wrap around will be AN15 to AN0.
Table 9-15. Available Result Data Formats.
SRES8
DJM
DSGN
Result Data Formats
Description and Bus Bit Mapping
1
0
0
8-bit / left justified / unsigned — bits 15:8
1
0
1
8-bit / left justified / signed — bits 15:8
1
1
X
8-bit / right justified / unsigned — bits 7:0
0
0
0
10-bit / left justified / unsigned — bits 15:6
0
0
1
10-bit / left justified / signed -— bits 15:6
0
1
X
10-bit / right justified / unsigned — bits 9:0
Table 9-16. Left Justified, Signed and Unsigned ATD Output Codes.
Input Signal
VRL = 0 Volts
VRH = 5.12 Volts
Signed
8-Bit Codes
Unsigned
8-Bit Codes
Signed
10-Bit Codes
Unsigned
10-Bit Codes
5.120 Volts
7F
FF
7FC0
FFC0
5.100
7F
FF
7F00
FF00
5.080
7E
FE
7E00
FE00
2.580
01
81
0100
8100
2.560
00
80
0000
8000
2.540
FF
7F
FF00
7F00
0.020
81
01
8100
0100
0.000
80
00
8000
0000
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
393
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-17. Analog Input Channel Select Coding
CD
CC
CB
CA
Analog Input
Channel
0
0
0
0
AN0
0
0
0
1
AN1
0
0
1
0
AN2
0
0
1
1
AN3
0
1
0
0
AN4
0
1
0
1
AN5
0
1
1
0
AN6
0
1
1
1
AN7
1
0
0
0
AN8
1
0
0
1
AN9
1
0
1
0
AN10
1
0
1
1
AN11
1
1
0
0
AN12
1
1
0
1
AN13
1
1
1
0
AN14
1
1
1
1
AN15
MC9S12XHZ512 Data Sheet, Rev. 1.06
394
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.7
ATD Status Register 0 (ATDSTAT0)
This read-only register contains the Sequence Complete Flag, overrun flags for external trigger and FIFO
mode, and the conversion counter.
Module Base + 0x0006
7
6
R
5
4
ETORF
FIFOR
0
0
0
SCF
3
2
1
0
CC3
CC2
CC1
CC0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 9-9. ATD Status Register 0 (ATDSTAT0)
Read: Anytime
Write: Anytime (No effect on CC[3:0])
Table 9-18. ATDSTAT0 Field Descriptions
Field
7
SCF
5
ETORF
Description
Sequence Complete Flag — This flag is set upon completion of a conversion sequence. If conversion
sequences are continuously performed (SCAN = 1), the flag is set after each one is completed. This flag is
cleared when one of the following occurs:
• Write “1” to SCF
• Write to ATDCTL5 (a new conversion sequence is started)
• If AFFC = 1 and read of a result register
0 Conversion sequence not completed
1 Conversion sequence has completed
External Trigger Overrun Flag —While in edge trigger mode (ETRIGLE = 0), if additional active edges are
detected while a conversion sequence is in process the overrun flag is set. This flag is cleared when one of the
following occurs:
• Write “1” to ETORF
• Write to ATDCTL0,1,2,3,4 (a conversion sequence is aborted)
• Write to ATDCTL5 (a new conversion sequence is started)
0 No External trigger over run error has occurred
1 External trigger over run error has occurred
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
395
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-18. ATDSTAT0 Field Descriptions (continued)
Field
Description
4
FIFOR
FIFO Over Run Flag — This bit indicates that a result register has been written to before its associated
conversion complete flag (CCF) has been cleared. This flag is most useful when using the FIFO mode because
the flag potentially indicates that result registers are out of sync with the input channels. However, it is also
practical for non-FIFO modes, and indicates that a result register has been over written before it has been read
(i.e., the old data has been lost). This flag is cleared when one of the following occurs:
• Write “1” to FIFOR
• Start a new conversion sequence (write to ATDCTL5 or external trigger)
0 No over run has occurred
1 Overrun condition exists (result register has been written while associated CCFx flag remained set)
3:0
CC[3:0}
Conversion Counter — These 4 read-only bits are the binary value of the conversion counter. The conversion
counter points to the result register that will receive the result of the current conversion. For example, CC3 = 0,
CC2 = 1, CC1 = 1, CC0 = 0 indicates that the result of the current conversion will be in ATD Result Register 6.
If in non-FIFO mode (FIFO = 0) the conversion counter is initialized to zero at the begin and end of the
conversion sequence. If in FIFO mode (FIFO = 1) the register counter is not initialized. The conversion
counters wraps around when its maximum value is reached.
Aborting a conversion or starting a new conversion by write to an ATDCTL register (ATDCTL5-0) clears the
conversion counter even if FIFO=1.
MC9S12XHZ512 Data Sheet, Rev. 1.06
396
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.8
Reserved Register 0 (ATDTEST0)
Module Base + 0x0008
R
7
6
5
4
3
2
1
0
u
u
u
u
u
u
u
u
1
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected
Figure 9-10. Reserved Register 0 (ATDTEST0)
Read: Anytime, returns unpredictable values
Write: Anytime in special modes, unimplemented in normal modes
NOTE
Writing to this register when in special modes can alter functionality.
9.3.2.9
ATD Test Register 1 (ATDTEST1)
This register contains the SC bit used to enable special channel conversions.
Module Base + 0x0009
R
7
6
5
4
3
2
1
u
u
u
u
u
u
u
0
SC
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
0
0
0
u = Unaffected
Figure 9-11. Reserved Register 1 (ATDTEST1)
Read: Anytime, returns unpredictable values for bit 7 and bit 6
Write: Anytime
NOTE
Writing to this register when in special modes can alter functionality.
Table 9-19. ATDTEST1 Field Descriptions
Field
Description
0
SC
Special Channel Conversion Bit — If this bit is set, then special channel conversion can be selected using
CC, CB, and CA of ATDCTL5. Table 9-20 lists the coding.
0 Special channel conversions disabled
1 Special channel conversions enabled
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
397
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-20. Special Channel Select Coding
SC
CD
CC
CB
CA
Analog Input Channel
1
0
0
X
X
Reserved
9.3.2.10
1
0
1
0
0
VRH
1
0
1
0
1
VRL
1
0
1
1
0
(VRH+VRL) / 2
1
0
1
1
1
Reserved
1
1
X
X
X
Reserved
ATD Status Register 2 (ATDSTAT2)
This read-only register contains the Conversion Complete Flags CCF15 to CCF8.
Module Base + 0x000A
R
7
6
5
4
3
2
1
0
CCF15
CCF14
CCF13
CCF12
CCF11
CCF10
CCF9
CCF8
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 9-12. ATD Status Register 2 (ATDSTAT2)
Read: Anytime
Write: Anytime, no effect
Table 9-21. ATDSTAT2 Field Descriptions
Field
Description
7:0
CCF[15:8]
Conversion Complete Flag Bits — A conversion complete flag is set at the end of each conversion in a
conversion sequence. The flags are associated with the conversion position in a sequence (and also the result
register number). Therefore, CCF8 is set when the ninth conversion in a sequence is complete and the result
is available in result register ATDDR8; CCF9 is set when the tenth conversion in a sequence is complete and
the result is available in ATDDR9, and so forth. A flag CCFx (x = 15, 14, 13, 12, 11, 10, 9, 8) is cleared when
one of the following occurs:
• Write to ATDCTL5 (a new conversion sequence is started)
• If AFFC = 0 and read of ATDSTAT2 followed by read of result register ATDDRx
• If AFFC = 1 and read of result register ATDDRx
In case of a concurrent set and clear on CCFx: The clearing by method A) will overwrite the set. The clearing
by methods B) or C) will be overwritten by the set.
0 Conversion number x not completed
1 Conversion number x has completed, result ready in ATDDRx
MC9S12XHZ512 Data Sheet, Rev. 1.06
398
Freescale Semiconductor
Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.11
ATD Status Register 1 (ATDSTAT1)
This read-only register contains the Conversion Complete Flags CCF7 to CCF0
Module Base + 0x000B
R
7
6
5
4
3
2
1
0
CCF7
CCF6
CCF5
CCF4
CCF3
CCF2
CCF1
CCF0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 9-13. ATD Status Register 1 (ATDSTAT1)
Read: Anytime
Write: Anytime, no effect
Table 9-22. ATDSTAT1 Field Descriptions
Field
Description
7:0
CCF[7:0]
Conversion Complete Flag Bits — A conversion complete flag is set at the end of each conversion in a
conversion sequence. The flags are associated with the conversion position in a sequence (and also the result
register number). Therefore, CCF0 is set when the first conversion in a sequence is complete and the result is
available in result register ATDDR0; CCF1 is set when the second conversion in a sequence is complete and
the result is available in ATDDR1, and so forth. A CCF flag is cleared when one of the following occurs:
• Write to ATDCTL5 (a new conversion sequence is started)
• If AFFC = 0 and read of ATDSTAT1 followed by read of result register ATDDRx
• If AFFC = 1 and read of result register ATDDRx
In case of a concurrent set and clear on CCFx: The clearing by method A) will overwrite the set. The clearing
by methods B) or C) will be overwritten by the set.
Conversion number x not completed
Conversion number x has completed, result ready in ATDDRx
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.12
ATD Input Enable Register 0 (ATDDIEN0)
Module Base + 0x000C
7
6
5
4
3
2
1
0
IEN15
IEN14
IEN13
IEN12
IEN11
IEN10
IEN9
IEN8
0
0
0
0
0
0
0
0
R
W
Reset
Figure 9-14. ATD Input Enable Register 0 (ATDDIEN0)
Read: Anytime
Write: anytime
Table 9-23. ATDDIEN0 Field Descriptions
Field
Description
7:0
IEN[15:8]
ATD Digital Input Enable on Channel Bits — This bit controls the digital input buffer from the analog input
pin (ANx) to PTADx data register.
0 Disable digital input buffer to PTADx
1 Enable digital input buffer to PTADx.
Note: Setting this bit will enable the corresponding digital input buffer continuously. If this bit is set while
simultaneously using it as an analog port, there is potentially increased power consumption because the
digital input buffer maybe in the linear region.
9.3.2.13
ATD Input Enable Register 1 (ATDDIEN1)
Module Base + 0x000D
7
6
5
4
3
2
1
0
IEN7
IEN6
IEN5
IEN4
IEN3
IEN2
IEN1
IEN0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 9-15. ATD Input Enable Register 1 (ATDDIEN1)
Read: Anytime
Write: Anytime
Table 9-24. ATDDIEN1 Field Descriptions
Field
Description
7:0
IEN[7:0]
ATD Digital Input Enable on Channel Bits — This bit controls the digital input buffer from the analog input
pin (ANx) to PTADx data register.
0 Disable digital input buffer to PTADx
1 Enable digital input buffer to PTADx.
Note: Setting this bit will enable the corresponding digital input buffer continuously. If this bit is set while
simultaneously using it as an analog port, there is potentially increased power consumption because the
digital input buffer maybe in the linear region.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.14
Port Data Register 0 (PORTAD0)
The data port associated with the ATD is input-only. The port pins are shared with the analog A/D inputs
AN[15:8].
Module Base + 0x000E
R
7
6
5
4
3
2
1
0
PTAD15
PTAD14
PTAD13
PTAD12
PTAD11
PTAD10
PTAD9
PTAD8
1
1
1
1
1
1
1
1
AN15
AN14
AN13
AN12
AN11
AN10
AN9
AN8
W
Reset
Pin
Function
= Unimplemented or Reserved
Figure 9-16. Port Data Register 0 (PORTAD0)
Read: Anytime
Write: Anytime, no effect
The A/D input channels may be used for general-purpose digital input.
Table 9-25. PORTAD0 Field Descriptions
Field
Description
7:0
PTAD[15:8]
A/D Channel x (ANx) Digital Input Bits— If the digital input buffer on the ANx pin is enabled (IENx = 1) or
channel x is enabled as external trigger (ETRIGE = 1, ETRIGCH[3-0] = x, ETRIGSEL = 0) read returns the
logic level on ANx pin (signal potentials not meeting VIL or VIH specifications will have an indeterminate value)).
If the digital input buffers are disabled (IENx = 0) and channel x is not enabled as external trigger, read returns
a “1”.
Reset sets all PORTAD0 bits to “1”.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.15
Port Data Register 1 (PORTAD1)
The data port associated with the ATD is input-only. The port pins are shared with the analog A/D inputs
AN7-0.
Module Base + 0x000F
R
7
6
5
4
3
2
1
0
PTAD7
PTAD6
PTAD5
PTAD4
PTAD3
PTAD2
PTAD1
PTAD0
1
1
1
1
1
1
1
1
AN 7
AN6
AN5
AN4
AN3
AN2
AN1
AN0
W
Reset
Pin
Function
= Unimplemented or Reserved
Figure 9-17. Port Data Register 1 (PORTAD1)
Read: Anytime
Write: Anytime, no effect
The A/D input channels may be used for general-purpose digital input.
Table 9-26. PORTAD1 Field Descriptions
Field
Description
7:0
PTAD[7:8]
A/D Channel x (ANx) Digital Input Bits — If the digital input buffer on the ANx pin is enabled (IENx=1) or
channel x is enabled as external trigger (ETRIGE = 1, ETRIGCH[3-0] = x, ETRIGSEL = 0) read returns the
logic level on ANx pin (signal potentials not meeting VIL or VIH specifications will have an indeterminate value)).
If the digital input buffers are disabled (IENx = 0) and channel x is not enabled as external trigger, read returns
a “1”.
Reset sets all PORTAD1 bits to “1”.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.16
ATD Conversion Result Registers (ATDDRx)
The A/D conversion results are stored in 16 read-only result registers. The result data is formatted in the
result registers bases on two criteria. First there is left and right justification; this selection is made using
the DJM control bit in ATDCTL5. Second there is signed and unsigned data; this selection is made using
the DSGN control bit in ATDCTL5. Signed data is stored in 2’s complement format and only exists in left
justified format. Signed data selected for right justified format is ignored.
Read: Anytime
Write: Anytime in special mode, unimplemented in normal modes
9.3.2.16.1
Left Justified Result Data
Module Base + 0x0010 = ATDDR0H
0x0012 = ATDDR1H
0x0014 = ATDDR2H
0x0016 = ATDDR3H
7
R (10-BIT) BIT 9 MSB
R (8-BIT) BIT 7 MSB
0x0018 = ATDDR4H
0x001A = ATDDR5H
0x001C = ATDDR6H
0x001E = ATDDR7H
0x0020 = ATDDR8H
0x0022 = ATDDR9H
0x0024 = ATDDR10H
0x0026 = ATDDR11H
0x0028 = ATDDR12H
0x002A = ATDDR13H
0x002C = ATDDR14H
0x002E = ATDDR15H
6
5
4
3
2
1
0
BIT 8
BIT 6
BIT 7
BIT 5
BIT 6
BIT 4
BIT 5
BIT 3
BIT 4
BIT 2
BIT 3
BIT 1
BIT 2
BIT 0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 9-18. Left Justified, ATD Conversion Result Register x, High Byte (ATDDRxH)
0x0019 = ATDDR4L
0x001B = ATDDR5L
0x001D = ATDDR6L
0x001F = ATDDR7L
Module Base + 0x0011 = ATDDR0L
0x0013 = ATDDR1L
0x0015 = ATDDR2L
0x0017 = ATDDR3L
R (10-BIT)
R (8-BIT)
0x0021 = ATDDR8L
0x0023 = ATDDR9L
0x0025 = ATDDR10L
0x0027 = ATDDR11L
0x0029 = ATDDR12L
0x002B = ATDDR13L
0x002D = ATDDR14L
0x002F = ATDDR15L
7
6
5
4
3
2
1
0
BIT 1
u
BIT 0
u
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected
Figure 9-19. Left Justified, ATD Conversion Result Register x, Low Byte (ATDDRxL)
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.3.2.16.2
Right Justified Result Data
Module Base + 0x0010 = ATDDR0H,
0x0012 = ATDDR1H,
0x0014 = ATDDR2H,
0x0016 = ATDDR3H
R (10-BIT)
R (8-BIT)
0x0018 = ATDDR4H,
0x001A = ATDDR5H,
0x001C = ATDDR6H,
0x001E = ATDDR7H
0x0020 = ATDDR8H,
0x0022 = ATDDR9H,
0x0024 = ATDDR10H,
0x0026 = ATDDR11H
0x0028 = ATDDR12H,
0x002A = ATDDR13H,
0x002C = ATDDR14H,
0x002E = ATDDR15H
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
BIT 9 MSB
0
BIT 8
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 9-20. Right Justified, ATD Conversion Result Register x, High Byte (ATDDRxH)
Module Base + 0x0011 = ATDDR0L,
0x0013 = ATDDR1L,
0x0015 = ATDDR2L,
0x0017 = ATDDR3L
7
R (10-BIT)
BIT 7
R (8-BIT) BIT 7 MSB
0x0019 = ATDDR4L,
0x001B = ATDDR5L,
0x001D = ATDDR6L,
0x001F = ATDDR7L
0x0021 = ATDDR8L,
0x0023 = ATDDR9L,
0x0025 = ATDDR10L,
0x0027 = ATDDR11L
0x0029 = ATDDR12L,
0x002B = ATDDR13L,
0x002D = ATDDR14L,
0x002F = ATDDR15L
6
5
4
3
2
1
0
BIT 6
BIT 6
BIT 5
BIT 5
BIT 4
BIT 4
BIT 3
BIT 3
BIT 2
BIT 2
BIT 1
BIT 1
BIT 0
BIT 0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 9-21. Right Justified, ATD Conversion Result Register x, Low Byte (ATDDRxL)
9.4
Functional Description
The ATD10B16C is structured in an analog and a digital sub-block.
9.4.1
Analog Sub-block
The analog sub-block contains all analog electronics required to perform a single conversion. Separate
power supplies VDDA and VSSA allow to isolate noise of other MCU circuitry from the analog sub-block.
9.4.1.1
Sample and Hold Machine
The sample and hold (S/H) machine accepts analog signals from the external world and stores them as
capacitor charge on a storage node.
The sample process uses a two stage approach. During the first stage, the sample amplifier is used to
quickly charge the storage node.The second stage connects the input directly to the storage node to
complete the sample for high accuracy.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
When not sampling, the sample and hold machine disables its own clocks. The analog electronics continue
drawing their quiescent current. The power down (ADPU) bit must be set to disable both the digital clocks
and the analog power consumption.
The input analog signals are unipolar and must fall within the potential range of VSSA to VDDA.
9.4.1.2
Analog Input Multiplexer
The analog input multiplexer connects one of the 16 external analog input channels to the sample and hold
machine.
9.4.1.3
Sample Buffer Amplifier
The sample amplifier is used to buffer the input analog signal so that the storage node can be quickly
charged to the sample potential.
9.4.1.4
Analog-to-Digital (A/D) Machine
The A/D machine performs analog to digital conversions. The resolution is program selectable at either 8
or 10 bits. The A/D machine uses a successive approximation architecture. It functions by comparing the
stored analog sample potential with a series of digitally generated analog potentials. By following a binary
search algorithm, the A/D machine locates the approximating potential that is nearest to the sampled
potential.
When not converting the A/D machine disables its own clocks. The analog electronics continue drawing
quiescent current. The power down (ADPU) bit must be set to disable both the digital clocks and the analog
power consumption.
Only analog input signals within the potential range of VRL to VRH (A/D reference potentials) will result
in a non-railed digital output codes.
9.4.2
Digital Sub-Block
This subsection explains some of the digital features in more detail. See register descriptions for all details.
9.4.2.1
External Trigger Input
The external trigger feature allows the user to synchronize ATD conversions to the external environment
events rather than relying on software to signal the ATD module when ATD conversions are to take place.
The external trigger signal (out of reset ATD channel 15, configurable in ATDCTL1) is programmable to
be edge or level sensitive with polarity control. Table 9-27 gives a brief description of the different
combinations of control bits and their effect on the external trigger function.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
Table 9-27. External Trigger Control Bits
ETRIGLE
ETRIGP
ETRIGE
SCAN
Description
X
X
0
0
Ignores external trigger. Performs one conversion sequence and stops.
X
X
0
1
Ignores external trigger. Performs continuous conversion sequences.
0
0
1
X
Falling edge triggered. Performs one conversion sequence per trigger.
0
1
1
X
Rising edge triggered. Performs one conversion sequence per trigger.
1
0
1
X
Trigger active low. Performs continuous conversions while trigger is active.
1
1
1
X
Trigger active high. Performs continuous conversions while trigger is active.
During a conversion, if additional active edges are detected the overrun error flag ETORF is set.
In either level or edge triggered modes, the first conversion begins when the trigger is received. In both
cases, the maximum latency time is one bus clock cycle plus any skew or delay introduced by the trigger
circuitry.
After ETRIGE is enabled, conversions cannot be started by a write to ATDCTL5, but rather must be
triggered externally.
If the level mode is active and the external trigger both de-asserts and re-asserts itself during a conversion
sequence, this does not constitute an overrun. Therefore, the flag is not set. If the trigger remains asserted
in level mode while a sequence is completing, another sequence will be triggered immediately.
9.4.2.2
General-Purpose Digital Input Port Operation
The input channel pins can be multiplexed between analog and digital data. As analog inputs, they are
multiplexed and sampled to supply signals to the A/D converter. As digital inputs, they supply external
input data that can be accessed through the digital port registers (PORTAD0 & PORTAD1) (input-only).
The analog/digital multiplex operation is performed in the input pads. The input pad is always connected
to the analog inputs of the ATD10B16C. The input pad signal is buffered to the digital port registers. This
buffer can be turned on or off with the ATDDIEN0 & ATDDIEN1 register. This is important so that the
buffer does not draw excess current when analog potentials are presented at its input.
9.4.3
Operation in Low Power Modes
The ATD10B16C can be configured for lower MCU power consumption in three different ways:
• Stop Mode
Stop Mode: This halts A/D conversion. Exit from Stop mode will resume A/D conversion, But due
to the recovery time the result of this conversion should be ignored.
Entering stop mode causes all clocks to halt and thus the system is placed in a minimum power
standby mode. This halts any conversion sequence in progress. During recovery from stop mode,
there must be a minimum delay for the stop recovery time tSR before initiating a new ATD
conversion sequence.
• Wait Mode
Wait Mode with AWAI = 1: This halts A/D conversion. Exit from Wait mode will resume A/D
conversion, but due to the recovery time the result of this conversion should be ignored.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
•
Entering wait mode, the ATD conversion either continues or halts for low power depending on the
logical value of the AWAIT bit.
Freeze Mode
Writing ADPU = 0 (Note that all ATD registers remain accessible.): This aborts any A/D
conversion in progress.
In freeze mode, the ATD10B16C will behave according to the logical values of the FRZ1 and FRZ0
bits. This is useful for debugging and emulation.
NOTE
The reset value for the ADPU bit is zero. Therefore, when this module is
reset, it is reset into the power down state.
9.5
9.5.1
Initialization/Application Information
Setting up and starting an A/D conversion
The following describes a typical setup procedure for starting A/D conversions. It is highly recommended
to follow this procedure to avoid common mistakes.
Each step of the procedure will have a general remark and a typical example
9.5.1.1
Step 1
Power up the ATD and concurrently define other settings in ATDCTL2
Example: Write to ATDCTL2: ADPU=1 -> powers up the ATD, ASCIE=1 enable interrupt on finish of a
conversion sequence.
9.5.1.2
Step 2
Wait for the ATD Recovery Time tREC before you proceed with Step 3.
Example: Use the CPU in a branch loop to wait for a defined number of bus clocks.
9.5.1.3
Step 3
Configure how many conversions you want to perform in one sequence and define other settings in
ATDCTL3.
Example: Write S4C=1 to do 4 conversions per sequence.
9.5.1.4
Step 4
Configure resolution, sampling time and ATD clock speed in ATDCTL4.
Example: Use default for resolution and sampling time by leaving SRES8, SMP1 and SMP0 clear. For a
bus clock of 40MHz write 9 to PR4-0, this gives an ATD clock of 0.5*40MHz/(9+1) = 2MHz which is
within the allowed range for fATDCLK.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.5.1.5
Step 5
Configure starting channel, single/multiple channel, continuous or single sequence and result data format
in ATDCTL5. Writing ATDCTL5 will start the conversion, so make sure your write ATDCTL5 in the last
step.
Example: Leave CD, CC,CB,CA clear to start on channel AN0. Write MULT=1 to convert channel AN0
to AN3 in a sequence (4 conversion per sequence selected in ATDCTL3).
9.5.2
9.5.2.1
Aborting an A/D conversion
Step 1
Write to ATDCTL4. This will abort any ongoing conversion sequence.
(Do not use write to other ATDCTL registers to abort, as this under certain circumstances might not work
correctly.)
9.5.2.2
Step 2
Disable the ATD Interrupt by writing ASCIE=0 in ATDCTL2.
It is important to clear the interrupt enable at this point, prior to step 3, as depending on the device clock
gating it may not always be possible to clear it or the SCF flag once the module is disabled (ADPU=0).
9.5.2.3
Step 3
Clear the SCF flag by writing a 1 in ATDSTAT0.
(Remaining flags will be cleared with the next start of a conversions, but SCF flag should be cleared to
avoid SCF interrupt.)
9.5.2.4
Step 4
Power down ATD by writing ADPU=0 in ATDCTL2.
9.6
Resets
At reset the ATD10B16C is in a power down state. The reset state of each individual bit is listed within
Section 9.3, “Memory Map and Register Definition,” which details the registers and their bit fields.
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Chapter 9 Analog-to-Digital Converter (ATD10B16CV4) Block Description
9.7
Interrupts
The interrupt requested by the ATD10B16C is listed in Table 9-28. Refer to MCU specification for related
vector address and priority.
Table 9-28. ATD Interrupt Vectors
Interrupt Source
Sequence Complete Interrupt
CCR Mask
Local Enable
I bit
ASCIE in ATDCTL2
See Section 9.3.2, “Register Descriptions,” for further details.
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MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 10
Liquid Crystal Display (LCD32F4BV1) Block Description
10.1
Introduction
The LCD32F4BV1 driver module has 32 frontplane drivers and 4 backplane drivers so that a maximum of
128 LCD segments are controllable. Each segment is controlled by a corresponding bit in the LCD RAM.
Four multiplex modes (1/1, 1/2, 1/3, 1/4 duty), and three bias (1/1, 1/2, 1/3) methods are available. The V0
voltage is the lowest level of the output waveform and V3 becomes the highest level. All frontplane and
backplane pins can be multiplexed with other port functions.
The LCD32F4BV1 driver system consists of five major sub-modules:
• Timing and Control – consists of registers and control logic for frame clock generation, bias
voltage level select, frame duty select, backplane select, and frontplane select/enable to produce
the required frame frequency and voltage waveforms.
• LCD RAM – contains the data to be displayed on the LCD. Data can be read from or written to the
display RAM at any time.
• Frontplane Drivers – consists of 32 frontplane drivers.
• Backplane Drivers – consists of 4 backplane drivers.
• Voltage Generator – Based on voltage applied to VLCD, it generates the voltage levels for the
timing and control logic to produce the frontplane and backplane waveforms.
10.1.1
Features
The LCD32F4BV1 includes these distinctive features:
• Supports five LCD operation modes
• 32 frontplane drivers
• 4 backplane drivers
— Each frontplane has an enable bit respectively
• Programmable frame clock generator
• Programmable bias voltage level selector
• On-chip generation of 4 different output voltage levels
10.1.2
Modes of Operation
The LCD32F4BV1 module supports five operation modes with different numbers of backplanes and
different biasing levels. During pseudo stop mode and wait mode the LCD operation can be suspended
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
under software control. Depending on the state of internal bits, the LCD can operate normally or the LCD
clock generation can be turned off and the LCD32F4BV1 module enters a power conservation state.
This is a high level description only, detailed descriptions of operating modes are contained in
Section 10.4.2, “Operation in Wait Mode”, Section 10.4.3, “Operation in Pseudo Stop Mode”, and
Section 10.4.4, “Operation in Stop Mode”.
10.1.3
Block Diagram
Figure 10-1 is a block diagram of the LCD32F4BV1 module.
Internal Address/Data/Clocks
OSCCLK
Timing
and
Control
Logic
LCD
RAM
16 bytes
Prescaler
LCD Clock
V3
V3
V2
V2
Frontplane
Drivers
V1
Voltage
Generator
Backplane
Drivers
V0
V0
FP[31:0]
V1
VLCD
BP[3:0]
Figure 10-1. LCD32F4BV1 Block Diagram
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Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.2
External Signal Description
The LCD32F4BV1 module has a total of 37 external pins.
Table 10-1. Signal Properties
Name
Function
Reset State
4 backplane waveforms
BP[3:0]
Backplane waveform signals
that connect directly to the pads
High impedance
32 frontplane waveforms
FP[31:0] Frontplane waveform signals
that connect directly to the pads
High impedance
LCD voltage
10.2.1
Port
VLCD
LCD supply voltage
—
BP[3:0] — Analog Backplane Pins
This output signal vector represents the analog backplane waveforms of the LCD32F4BV1 module and is
connected directly to the corresponding pads.
10.2.2
FP[31:0] — Analog Frontplane Pins
This output signal vector represents the analog frontplane waveforms of the LCD32F4BV1 module and is
connected directly to the corresponding pads.
10.2.3
VLCD — LCD Supply Voltage Pin
Positive supply voltage for the LCD waveform generation.
10.3
Memory Map and Register Definition
This section provides a detailed description of all memory and registers.
10.3.1
Module Memory Map
The memory map for the LCD32F4BV1 module is given in Table 10-2. The address listed for each register
is the address offset. The total address for each register is the sum of the base address for the
LCD32F4BV1 module and the address offset for each register.
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Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
Table 10-2. LCD32F4BV1 Memory Map
Address
Offset
Use
Access
0x0000
LCD Control Register 0 (LCDCR0)
Read/Write
0x0001
LCD Control Register 1 (LCDCR1)
Read/Write
0x0002
LCD Frontplane Enable Register 0 (FPENR0)
Read/Write
0x0003
LCD Frontplane Enable Register 1 (FPENR1)
Read/Write
0x0004
LCD Frontplane Enable Register 2 (FPENR2)
Read/Write
0x0005
LCD Frontplane Enable Register 3 (FPENR3)
Read/Write
0x0006
Unimplemented
0x0007
Unimplemented
0x0008
LCDRAM (Location 0)
Read/Write
0x0009
LCDRAM (Location 1)
Read/Write
0x000A
LCDRAM (Location 2)
Read/Write
0x000B
LCDRAM (Location 3)
Read/Write
0x000C
LCDRAM (Location 4)
Read/Write
0x000D
LCDRAM (Location 5)
Read/Write
0x000E
LCDRAM (Location 6)
Read/Write
0x000F
LCDRAM (Location 7)
Read/Write
0x0010
LCDRAM (Location 8)
Read/Write
0x0011
LCDRAM (Location 9)
Read/Write
0x0012
LCDRAM (Location 10)
Read/Write
0x0013
LCDRAM (Location 11)
Read/Write
0x0014
LCDRAM (Location 12)
Read/Write
0x0015
LCDRAM (Location 13)
Read/Write
0x0016
LCDRAM (Location 14)
Read/Write
0x0017
LCDRAM (Location 15)
Read/Write
MC9S12XHZ512 Data Sheet, Rev. 1.06
414
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.3.2
Register Descriptions
This section consists of register descriptions. Each description includes a standard register diagram.
Details of register bit and field function follow the register diagrams, in bit order.
10.3.2.1
LCD Control Register 0 (LCDCR0)
Module Base + 0x0000
7
6
R
5
4
3
2
1
0
LCLK2
LCLK1
LCLK0
BIAS
DUTY1
DUTY0
0
0
0
0
0
0
0
LCDEN
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-2. LCD Control Register 0 (LCDCR0)
Read: anytime
Write: LCDEN anytime. To avoid segment flicker the clock prescaler bits, the bias select bit and the duty
select bits must not be changed when the LCD is enabled.
Table 10-3. LCDCR0 Field Descriptions
Field
7
LCDEN
Description
LCD32F4BV1 Driver System Enable — The LCDEN bit starts the LCD waveform generator.
0 All frontplane and backplane pins are disabled. In addition, the LCD32F4BV1 system is disabled
and all LCD waveform generation clocks are stopped.
1 LCD driver system is enabled. All FP[31:0] pins with FP[31:0]EN set, will output an LCD driver
waveform The BP[3:0] pins will output an LCD32F4BV1 driver waveform based on the settings of DUTY0
and DUTY1.
5:3
LCLK[2:0]
LCD Clock Prescaler — The LCD clock prescaler bits determine the OSCCLK divider value to produce the LCD
clock frequency. For detailed description of the correlation between LCD clock prescaler bits and the divider
value please refer to Table 10-7.
2
BIAS
BIAS Voltage Level Select — This bit selects the bias voltage levels during various LCD operating modes, as
shown in Table 10-8.
1:0
DUTY[1:0]
LCD Duty Select — The DUTY1 and DUTY0 bits select the duty (multiplex mode) of the LCD32F4BV1 driver
system, as shown in Table 10-8.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
415
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.3.2.2
LCD Control Register 1 (LCDCR1)
Module Base + 0x0001
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
LCDSWAI
LCDRPSTP
0
0
W
Reset
0
0
0
0
0
0
Unimplemented or Reserved
Figure 10-3. LCD Control Register 1 (LCDCR1)
Read: anytime
Write: anytime
Table 10-4. LCDCR1 Field Descriptions
Field
1
LCDSWAI
Description
LCD Stop in Wait Mode — This bit controls the LCD operation while in wait mode.
0 LCD operates normally in wait mode.
1 Stop LCD32F4BV1 driver system when in wait mode.
0
LCD Run in Pseudo Stop Mode — This bit controls the LCD operation while in pseudo stop mode.
LCDRPSTP 0 Stop LCD32F4BV1 driver system when in pseudo stop mode.
1 LCD operates normally in pseudo stop mode.
10.3.2.3
LCD Frontplane Enable Register 0–3 (FPENR0–FPENR3)
Module Base + 0x0002
7
6
5
4
3
2
1
0
FP7EN
FP6EN
FP5EN
FP4EN
FP3EN
FP2EN
FP1EN
FP0EN
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-4. LCD Frontplane Enable Register 0 (FPENR0)
Module Base + 0x0003
7
6
5
4
3
2
1
0
FP15EN
FP14EN
FP13EN
FP12EN
FP11EN
FP10EN
FP9EN
FP8EN
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-5. LCD Frontplane Enable Register 1 (FPENR1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
416
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
Module Base + 0x0004
7
6
5
4
3
2
1
0
FP23EN
FP22EN
FP21EN
FP20EN
FP19EN
FP18EN
FP17EN
FP16EN
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-6. LCD Frontplane Enable Register 2 (FPENR2)
Module Base + 0x0005
7
6
5
4
3
2
1
0
FP31EN
FP30EN
FP29EN
FP28EN
FP27EN
FP26EN
FP25EN
FP24EN
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-7. LCD Frontplane Enable Register 3 (FPENR3)
These bits enable the frontplane output waveform on the corresponding frontplane pin when LCDEN = 1.
Read: anytime
Write: anytime
Table 10-5. FPENR0–FPENR3 Field Descriptions
Field
Description
31:0
Frontplane Output Enable — The FP[31:0]EN bit enables the frontplane driver outputs. If LCDEN = 0, these
FP[31:0]EN bits have no effect on the state of the I/O pins. It is recommended to set FP[31:0]EN bits before LCDEN is set.
0 Frontplane driver output disabled on FP[31:0].
1 Frontplane driver output enabled on FP[31:0].
10.3.2.4
LCD RAM (LCDRAM)
The LCD RAM consists of 16 bytes. After reset the LCD RAM contents will be indeterminate (I), as
indicated by Figure 10-8.
0x0008
R
LCDRAM
W
7
6
5
4
3
2
1
0
FP1BP3
FP1BP2
FP1BP1
FP1BP0
FP0BP3
FP0BP2
FP0BP1
FP0BP0
I
I
I
I
I
I
I
I
FP3BP3
FP3BP2
FP3BP1
FP3BP0
FP2BP3
FP2BP2
FP2BP1
FP2BP0
I
I
I
I
I
I
I
I
FP5BP3
FP5BP2
FP5BP1
FP5BP0
FP4BP3
FP4BP2
FP4BP1
FP4BP0
I
I
I
I
I
I
I
I
Reset
0x0009
R
LCDRAM
W
Reset
0x000A
R
LCDRAM
W
Reset
I = Value is indeterminate
Figure 10-8. LCD RAM (LCDRAM)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
417
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
0x000B
R
LCDRAM
W
FP7BP3
FP7BP2
FP7BP1
FP7BP0
FP6BP3
FP6BP2
FP6BP1
FP6BP0
I
I
I
I
I
I
I
I
FP9BP3
FP9BP2
FP9BP1
FP9BP0
FP8BP3
FP8BP2
FP8BP1
FP8BP0
I
I
I
I
I
I
I
I
FP11BP3
FP11BP2
FP11BP1
FP11BP0
FP10BP3
FP10BP2
FP10BP1
FP10BP0
I
I
I
I
I
I
I
I
FP13BP3
FP13BP2
FP13BP1
FP13BP0
FP12BP3
FP12BP2
FP12BP1
FP12BP0
I
I
I
I
I
I
I
I
FP15BP3
FP15BP2
FP15BP1
FP15BP0
FP14BP3
FP14BP2
FP14BP1
FP14BP0
I
I
I
I
I
I
I
I
FP17BP3
FP17BP2
FP17BP1
FP17BP0
FP16BP3
FP16BP2
FP16BP1
FP16BP0
I
I
I
I
I
I
I
I
FP19BP3
FP19BP2
FP19BP1
FP19BP0
FP18BP3
FP18BP2
FP18BP1
FP18BP0
I
I
I
I
I
I
I
I
FP21BP3
FP21BP2
FP21BP1
FP21BP0
FP20BP3
FP20BP2
FP20BP1
FP20BP0
I
I
I
I
I
I
I
I
FP23BP3
FP23BP2
FP23BP1
FP23BP0
FP22BP3
FP22BP2
FP22BP1
FP22BP0
I
I
I
I
I
I
I
I
FP25BP3
FP25BP2
FP25BP1
FP25BP0
FP24BP3
FP24BP2
FP24BP1
FP24BP0
I
I
I
I
I
I
I
I
FP27BP3
FP27BP2
FP27BP1
FP27BP0
FP26BP3
FP26BP2
FP26BP1
FP26BP0
I
I
I
I
I
I
I
I
FP29BP3
FP29BP2
FP29BP1
FP29BP0
FP28BP3
FP28BP2
FP28BP1
FP28BP0
I
I
I
I
I
I
I
I
FP31BP3
FP31BP2
FP31BP1
FP31BP0
FP30BP3
FP30BP2
FP30BP1
FP30BP0
I
I
I
I
I
I
I
I
Reset
0x000C
R
LCDRAM
W
Reset
0x000D
R
LCDRAM
W
Reset
0x000E
R
LCDRAM
W
Reset
0x000F
R
LCDRAM
W
Reset
0x0010
R
LCDRAM
W
Reset
0x0011
R
LCDRAM
W
Reset
0x0012
R
LCDRAM
W
Reset
0x0013
R
LCDRAM
W
Reset
0x0014
R
LCDRAM
W
Reset
0x0015
R
LCDRAM
W
Reset
0x0016
R
LCDRAM
W
Reset
0x0017
R
LCDRAM
W
Reset
I = Value is indeterminate
Figure 10-8. LCD RAM (LCDRAM) (continued)
MC9S12XHZ512 Data Sheet, Rev. 1.06
418
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
Read: anytime
Write: anytime
Table 10-6. LCD RAM Field Descriptions
Field
Description
31:0
3:0
FP[31:0]
BP[3:0]
LCD Segment ON — The FP[31:0]BP[3:0] bit displays (turns on) the LCD segment connected between FP[31:0]
and BP[3:0].
0 LCD segment OFF
1 LCD segment ON
10.4
Functional Description
This section provides a complete functional description of the LCD32F4BV1 block, detailing the
operation of the design from the end user perspective in a number of subsections.
10.4.1
10.4.1.1
LCD Driver Description
Frontplane, Backplane, and LCD System During Reset
During a reset the following conditions exist:
• The LCD32F4BV1 system is configured in the default mode, 1/4 duty and 1/3 bias, that means all
backplanes are used.
• All frontplane enable bits, FP[31:0]EN are cleared and the ON/OFF control for the display, the
LCDEN bit is cleared, thereby forcing all frontplane and backplane driver outputs to the high
impedance state. The MCU pin state during reset is defined by the port integration module (PIM).
10.4.1.2
LCD Clock and Frame Frequency
The frequency of the oscillator clock (OSCCLK) and divider determine the LCD clock frequency. The
divider is set by the LCD clock prescaler bits, LCLK[2:0], in the LCD control register 0 (LCDCR0).
Table 10-7 shows the LCD clock and frame frequency for some multiplexed mode at OSCCLK = 16 MHz,
8 MHz, 4 MHz, 2 MHz, 1 MHz, and 0.5 MHz.
Table 10-7. LCD Clock and Frame Frequency
Oscillator
Frequency in
MHz
LCD Clock Prescaler
Divider
Frame Frequency [Hz]
LCD Clock
Frequency [Hz]
1/1 Duty
1/2 Duty
1/3 Duty
1/4 Duty
LCLK2
LCLK1
LCLK0
OSCCLK = 0.5
0
0
0
0
0
1
1024
2048
488
244
488
244
244
122
163
81
122
61
OSCCLK = 1.0
0
0
0
1
1
0
2048
4096
488
244
488
244
244
122
163
81
122
61
OSCCLK = 2.0
0
0
1
1
0
1
4096
8192
488
244
488
244
244
122
163
81
122
61
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
419
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
Table 10-7. LCD Clock and Frame Frequency
Oscillator
Frequency in
MHz
LCD Clock Prescaler
Divider
Frame Frequency [Hz]
LCD Clock
Frequency [Hz]
1/1 Duty
1/2 Duty
1/3 Duty
1/4 Duty
LCLK2
LCLK1
LCLK0
OSCCLK = 4.0
0
1
1
0
1
0
8192
16384
488
244
488
244
244
122
163
81
122
61
OSCCLK = 8.0
1
1
0
0
0
1
16384
32768
488
244
488
244
244
122
163
81
122
61
OSCCLK = 16.0
1
1
1
1
0
1
65536
131072
244
122
244
122
122
61
81
40
61
31
For other combinations of OSCCLK and divider not shown in Table 10-7, the following formula may be
used to calculate the LCD frame frequency for each multiplex mode:
OSCCLK (Hz)
LCD Frame Frequency (Hz) = ----------------------------------- ⋅ Duty
Divider
The possible divider values are shown in Table 10-7.
10.4.1.3
LCD RAM
For a segment on the LCD to be displayed, data must be written to the LCD RAM which is shown in
Section 10.3, “Memory Map and Register Definition”. The 128 bits in the LCD RAM correspond to the
128 segments that are driven by the frontplane and backplane drivers. Writing a 1 to a given location will
result in the corresponding display segment being driven with a differential RMS voltage necessary to turn
the segment ON when the LCDEN bit is set and the corresponding FP[31:0]EN bit is set. Writing a 0 to a
given location will result in the corresponding display segment being driven with a differential RMS
voltage necessary to turn the segment OFF. The LCD RAM is a dual port RAM that interfaces with the
internal address and data buses of the MCU. It is possible to read from LCD RAM locations for scrolling
purposes. When LCDEN = 0, the LCD RAM can be used as on-chip RAM. Writing or reading of the
LCDEN bit does not change the contents of the LCD RAM. After a reset, the LCD RAM contents will be
indeterminate.
10.4.1.4
LCD Driver System Enable and Frontplane Enable Sequencing
If LCDEN = 0 (LCD32F4BV1 driver system disabled) and the frontplane enable bit, FP[31:0]EN, is set,
the frontplane driver waveform will not appear on the output until LCDEN is set. If LCDEN = 1
(LCD32F4BV1 driver system enabled), the frontplane driver waveform will appear on the output as soon
as the corresponding frontplane enable bit, FP[31:0]EN, in the registers FPENR0–FPENR3 is set.
10.4.1.5
LCD Bias and Modes of Operation
The LCD32F4BV1 driver has five modes of operation:
• 1/1 duty (1 backplane), 1/1 bias (2 voltage levels)
• 1/2 duty (2 backplanes), 1/2 bias (3 voltage levels)
• 1/2 duty (2 backplanes), 1/3 bias (4 voltage levels)
MC9S12XHZ512 Data Sheet, Rev. 1.06
420
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
•
•
1/3 duty (3 backplanes), 1/3 bias (4 voltage levels)
1/4 duty (4 backplanes), 1/3 bias (4 voltage levels)
The voltage levels required for the different operating modes are generated internally based on VLCD.
Changing VLCD alters the differential RMS voltage across the segments in the ON and OFF states,
thereby setting the display contrast.
The backplane waveforms are continuous and repetitive every frame. They are fixed within each operating
mode and are not affected by the data in the LCD RAM.
The frontplane waveforms generated are dependent on the state (ON or OFF) of the LCD segments as
defined in the LCD RAM. The LCD32F4BV1 driver hardware uses the data in the LCD RAM to construct
the frontplane waveform to create a differential RMS voltage necessary to turn the segment ON or OFF.
The LCD duty is decided by the DUTY1 and DUTY0 bits in the LCD control register 0 (LCDCR0). The
number of bias voltage levels is determined by the BIAS bit in LCDCR0. Table 10-8 summarizes the
multiplex modes (duties) and the bias voltage levels that can be selected for each multiplex mode (duty).
The backplane pins have their corresponding backplane waveform output BP[3:0] in high impedance state
when in the OFF state as indicated in Table 10-8. In the OFF state the corresponding pins BP[3:0]can be
used for other functionality, for example as general purpose I/O ports.
Table 10-8. LCD Duty and Bias
LCDCR0 Register
Backplanes
Bias (BIAS = 0)
Bias (BIAS = 1)
Duty
DUTY1
DUTY0
BP3
BP2
BP1
BP0
1/1
1/2
1/3
1/1
1/2
1/3
1/1
0
1
OFF
OFF
OFF
BP0
YES
NA
NA
YES
NA
NA
1/2
1
0
OFF
OFF
BP1
BP0
NA
YES
NA
NA
NA
YES
1/3
1
1
OFF
BP2
BP1
BP0
NA
NA
YES
NA
NA
YES
1/4
0
0
BP3
BP2
BP1
BP0
NA
NA
YES
NA
NA
YES
10.4.2
Operation in Wait Mode
The LCD32F4BV1 driver system operation during wait mode is controlled by the LCD stop in wait
(LCDSWAI) bit in the LCD control register 1 (LCDCR1). If LCDSWAI is reset, the LCD32F4BV1 driver
system continues to operate during wait mode. If LCDSWAI is set, the LCD32F4BV1 driver system is
turned off during wait mode. In this case, the LCD waveform generation clocks are stopped and the
LCD32F4BV1 drivers pull down to VSSX those frontplane and backplane pins that were enabled before
entering wait mode. The contents of the LCD RAM and the LCD registers retain the values they had prior
to entering wait mode.
10.4.3
Operation in Pseudo Stop Mode
The LCD32F4BV1 driver system operation during pseudo stop mode is controlled by the LCD run in
pseudo stop (LCDRPSTP) bit in the LCD control register 1 (LCDCR1). If LCDRPSTP is reset, the
LCD32F4BV1 driver system is turned off during pseudo stop mode. In this case, the LCD waveform
generation clocks are stopped and the LCD32F4BV1 drivers pull down to VSSX those frontplane and
backplane pins that were enabled before entering pseudo stop mode. If LCDRPSTP is set, the
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
421
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
LCD32F4BV1 driver system continues to operate during pseudo stop mode. The contents of the LCD
RAM and the LCD registers retain the values they had prior to entering pseudo stop mode.
10.4.4
Operation in Stop Mode
All LCD32F4BV1 driver system clocks are stopped, the LCD32F4BV1 driver system pulls down to VSSX
those frontplane and backplane pins that were enabled before entering stop mode. Also, during stop mode,
the contents of the LCD RAM and the LCD registers retain the values they had prior to entering stop mode.
As a result, after exiting from stop mode, the LCD32F4BV1 driver system clocks will run (if LCDEN =
1) and the frontplane and backplane pins retain the functionality they had prior to entering stop mode.
10.4.5
LCD Waveform Examples
Figure 10-9 through Figure 10-13 show the timing examples of the LCD output waveforms for the
available modes of operation.
MC9S12XHZ512 Data Sheet, Rev. 1.06
422
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.4.5.1
1/1 Duty Multiplexed with 1/1 Bias Mode
Duty = 1/1:DUTY1 = 0, DUTY0 = 1
Bias = 1/1:BIAS = 0 or BIAS = 1
V0 = V1 = VSSX, V2 = V3 = VLCD
- BP1, BP2, and BP3 are not used, a maximum of 32 segments are displayed.
1 Frame
VLCD
BP0
VSSX
VLCD
FPx (xxx0)
VSSX
VLCD
FPy (xxx1)
VSSX
+VLCD
0
BP0-FPx (OFF)
-VLCD
+VLCD
0
BP0-FPy (ON)
-VLCD
Figure 10-9. 1/1 Duty and 1/1 Bias
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
423
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.4.5.2
1/2 Duty Multiplexed with 1/2 Bias Mode
Duty = 1/2:DUTY1 = 1, DUTY0 = 0
Bias = 1/2:BIAS = 0
V0 = VSSX, V1 = V2 = VLCD * 1/2, V3 = VLCD
- BP2 and BP3 are not used, a maximum of 64 segments are displayed.
1 Frame
BP0
VLCD
VLCD × 1/2
VSSX
BP1
VLCD
VLCD × 1/2
VSSX
FPx (xx10)
VLCD
VLCD × 1/2
VSSX
FPy (xx00)
VLCD
VLCD × 1/2
VSSX
FPz (xx11)
VLCD
VLCD × 1/2
VSSX
BP0-FPx (OFF)
+VLCD
+VLCD × 1/2
0
-VLCD × 1/2
-VLCD
BP1-FPx (ON)
+VLCD
+VLCD × 1/2
0
-VLCD × 1/2
-VLCD
BP0-FPy (OFF)
+VLCD
+VLCD × 1/2
0
-VLCD × 1/2
-VLCD
BP0-FPz (ON)
+VLCD
+VLCD × 1/2
0
-VLCD × 1/2
-VLCD
Figure 10-10. 1/2 Duty and 1/2 Bias
MC9S12XHZ512 Data Sheet, Rev. 1.06
424
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.4.5.3
1/2 Duty Multiplexed with 1/3 Bias Mode
Duty = 1/2:DUTY1 = 1, DUTY0 = 0
Bias = 1/3:BIAS = 1
V0 = VSSX, V1 = VLCD * 1/3, V2 = VLCD * 2/3, V3 = VLCD
- BP2 and BP3 are not used, a maximum of 64 segments are displayed.
1 Frame
BP0
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP1
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
FPx (xx10)
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
FPy (xx00)
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
FPz (xx11)
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP0-FPx (OFF)
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP1-FPx (ON)
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP0-FPy (OFF)
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP0-FPz (ON)
Figure 10-11. 1/2 Duty and 1/3 Bias
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
425
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.4.5.4
1/3 Duty Multiplexed with 1/3 Bias Mode
Duty = 1/3:DUTY1 = 1, DUTY0 = 1
Bias = 1/3:BIAS = 0 or BIAS = 1
V0 = VSSX, V1 = VLCD * 1/3, V2 = VLCD * 2/3, V3 = VLCD
- BP3 is not used, a maximum of 96 segments are displayed.
1 Frame
BP0
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP1
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP2
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
FPx (x010)
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP0-FPx (OFF)
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP1-FPx (ON)
Figure 10-12. 1/3 Duty and 1/3 Bias
MC9S12XHZ512 Data Sheet, Rev. 1.06
426
Freescale Semiconductor
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.4.5.5
1/4 Duty Multiplexed with 1/3 Bias Mode
Duty = 1/4:DUTY1 = 0, DUTY0 = 0
Bias = 1/3:BIAS = 0 or BIAS = 1
V0 = VSSX, V1 = VLCD * 1/3, V2 = VLCD * 2/3, V3 = VLCD
- A maximum of 128 segments are displayed.
1 Frame
BP0
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP1
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP2
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
BP3
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
FPx (1001)
VLCD
VLCD × 2/3
VLCD × 1/3
VSSX
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP0-FPx (ON)
+VLCD
+VLCD × 2/3
+VLCD × 1/3
0
-VLCD × 1/3
-VLCD × 2/3
-VLCD
BP1-FPx (OFF)
Figure 10-13. 1/4 Duty and 1/3 Bias
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
427
Chapter 10 Liquid Crystal Display (LCD32F4BV1) Block Description
10.5
Resets
The reset values of registers and signals are described in Section 10.3, “Memory Map and Register
Definition”. The behavior of the LCD32F4BV1 system during reset is described in Section 10.4.1, “LCD
Driver Description”.
10.6
Interrupts
This module does not generate any interrupts.
MC9S12XHZ512 Data Sheet, Rev. 1.06
428
Freescale Semiconductor
Chapter 11
Motor Controller (MC10B12CV2) Block Description
11.1
Introduction
The block MC10B12C is a PWM motor controller suitable to drive instruments in a cluster configuration
or any other loads requiring a PWM signal. The motor controller has twelve PWM channels associated
with two pins each (24 pins in total).
11.1.1
Features
The MC_10B12C includes the following features:
• 10/11-bit PWM counter
• 11-bit resolution with selectable PWM dithering function
• 7-bit resolution mode (fast mode): duty cycle can be changed by accessing only 1 byte/output
• Left, right, or center aligned PWM
• Output slew rate control
• This module is suited for, but not limited to, driving small stepper and air core motors used in
instrumentation applications. This module can be used for other motor control or PWM
applications that match the frequency, resolution, and output drive capabilities of the module.
11.1.2
Modes of Operation
11.1.2.1
Functional Modes
11.1.2.1.1
PWM Resolution
The motor controller can be configured to either 11- or 7-bits resolution mode by clearing or setting the
FAST bit. This bit influences all PWM channels. For details, please refer to Section 11.3.2.5, “Motor
Controller Duty Cycle Registers”.
11.1.2.1.2
Dither Function
Dither function can be selected or deselected by setting or clearing the DITH bit. This bit influences all
PWM channels. For details, please refer to Section 11.4.1.3.5, “Dither Bit (DITH)”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
429
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.1.2.2
PWM Channel Configuration Modes
The twelve PWM channels can operate in three functional modes. Those modes are, with some
restrictions, selectable for each channel independently.
11.1.2.2.1
Dual Full H-Bridge Mode
This mode is suitable to drive a stepper motor or a 360o air gauge instrument. For details, please refer to
Section 11.4.1.1.1, “Dual Full H-Bridge Mode (MCOM = 11)”. In this mode two adjacent PWM channels
are combined, and two PWM channels drive four pins.
11.1.2.2.2
Full H-Bridge Mode
This mode is suitable to drive any load requiring a PWM signal in a H-bridge configuration using two pins.
For details please refer to Section 11.4.1.1.2, “Full H-Bridge Mode (MCOM = 10)”.
11.1.2.2.3
Half H-Bridge Mode
This mode is suitable to drive a 90o instrument driven by one pin. For details, please refer to
Section 11.4.1.1.3, “Half H-Bridge Mode (MCOM = 00 or 01)”.
11.1.2.3
PWM Alignment Modes
Each PWM channel can operate independently in three different alignment modes. For details, please refer
to Section 11.4.1.3.1, “PWM Alignment Modes”.
11.1.2.4
Low-Power Modes
The behavior of the motor controller in low-power modes is programmable. For details, please refer to
Section 11.4.5, “Operation in Wait Mode” and Section 11.4.6, “Operation in Stop and Pseudo-Stop
Modes”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
430
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.1.3
Block Diagram
Control Registers
FAST
DITH
Period Register
11-Bit Timer/Counter
PWM Channel Pair
PWM Channel
11
Duty Register 0
Comparator
M0C0M
M0C0P
Duty Register 1
Comparator
M0C1M
M0C1P
Duty Register 2
Comparator
M1C0M
M1C0P
Duty Register 3
Comparator
M1C1M
M1C1P
Duty Register 4
Comparator
M2C0M
M2C0P
Duty Register 5
Comparator
M2C1M
M2C1P
Duty Register 6
Comparator
M3C0M
M3C0P
Duty Register 7
Comparator
M3C1M
M3C1P
Duty Register 8
Comparator
M4C0M
M4C0P
Duty Register 9
Comparator
M4C1M
M4C1P
Duty Register 10
Comparator
M5C0M
M5C0P
Duty Register 11
Comparator
M5C1M
M5C1P
Figure 11-1. MC10B12C Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
431
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.2
External Signal Description
The motor controller is associated with 24 pins. Table 11-1 lists the relationship between the PWM
channels and signal pins as well as PWM channel pair (motor number), coils, and nodes they are supposed
to drive if all channels are set to dual full H-bridge configuration.
Table 11-1. PWM Channel and Pin Assignment
Pin Name
PWM Channel
PWM Channel Pair1
Coil
Node
M0C0M
0
0
0
Minus
1
Minus
M0C0P
M0C1M
Plus
1
M0C1P
M1C0M
Plus
2
1
0
M1C0P
M1C1M
Plus
3
1
Minus
0
Minus
1
Minus
M1C1P
M2C0M
Plus
4
2
M2C0P
M2C1M
Plus
5
M2C1P
M3C0M
Plus
6
3
0
M3C0P
M3C1M
7
1
Minus
0
Minus
1
Minus
Plus
8
4
M4C0P
M4C1M
Plus
9
M4C1P
M5C0M
Plus
10
5
0
M5C0P
M5C1M
11.2.1
Minus
Plus
11
M5C1P
1
Minus
Plus
M3C1P
M4C0M
Minus
1
Minus
Plus
A PWM Channel Pair always consists of PWM channel x and PWM channel x+1 (x = 2⋅n). The term
“PWM Channel Pair” is equivalent to the term “Motor”. E.g. Channel Pair 0 is equivalent to Motor 0
M0C0M/M0C0P/M0C1M/M0C1P — PWM Output Pins for Motor 0
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 0. PWM output on M0C0M results in a positive current flow through coil 0 when M0C0P is driven
to a logic high state. PWM output on M0C1M results in a positive current flow through coil 1 when M0C1P
is driven to a logic high state.
MC9S12XHZ512 Data Sheet, Rev. 1.06
432
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.2.2
M1C0M/M1C0P/M1C1M/M1C1P — PWM Output Pins for Motor 1
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 1. PWM output on M1C0M results in a positive current flow through coil 0 when M1C0P is driven
to a logic high state. PWM output on M1C1M results in a positive current flow through coil 1 when M1C1P
is driven to a logic high state.
11.2.3
M2C0M/M2C0P/M2C1M/M2C1P — PWM Output Pins for Motor 2
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 2. PWM output on M2C0M results in a positive current flow through coil 0 when M2C0P is driven
to a logic high state. PWM output on M2C1M results in a positive current flow through coil 1 when M2C1P
is driven to a logic high state.
11.2.4
M3C0M/M3C0P/M3C1M/M3C1P — PWM Output Pins for Motor 3
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 3. PWM output on M3C0M results in a positive current flow through coil 0 when M3C0P is driven
to a logic high state. PWM output on M3C1M results in a positive current flow through coil 1 when M3C1P
is driven to a logic high state.
11.2.5
M4C0M/M4C0P/M4C1M/M4C1P — PWM Output Pins for Motor 4
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 4. PWM output on M4C0M results in a positive current flow through coil 0 when M4C0P is driven
to a logic high state. PWM output on M4C1M results in a positive current flow through coil 1 when M4C1P
is driven to a logic high state.
11.2.6
M5C0M/M5C0P/M5C1M/M5C1P — PWM Output Pins for Motor 5
High current PWM output pins that can be used for motor drive. These pins interface to the coils of
motor 5. PWM output on M5C0M results in a positive current flow through coil 0 when M5C0P is driven
to a logic high state. PWM output on M5C1M results in a positive current flow through coil 1 when M5C1P
is driven to a logic high state.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
433
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.3
Memory Map and Register Definition
This section provides a detailed description of all registers of the 10-bit 12-channel motor controller
module.
11.3.1
Module Memory Map
Table 11-2 shows the memory map of the 10-bit 12-channel motor controller module.
Table 11-2. MC10B12C - Memory Map
Address offset
Use
Access
$00
MCCTL0
RW
$01
MCCTL1
RW
$02
MCPER (high byte)
RW
$03
MCPER (low byte)
RW
$04
Reserved
-
$05
Reserved
-
$06
Reserved
-
$07
Reserved
-
$08
Reserved
-
$09
Reserved
-
$0A
Reserved
-
$0B
Reserved
-
$0C
Reserved
-
$0D
Reserved
-
$0E
Reserved
-
$0F
Reserved
-
$10
MCCC0
RW
$11
MCCC1
RW
$12
MCCC2
RW
$13
MCCC3
RW
$14
MCCC4
RW
$15
MCCC5
RW
$16
MCCC6
RW
$17
MCCC7
RW
$18
MCCC8
RW
$19
MCCC9
RW
$1A
MCCC10
RW
$1B
MCCC11
RW
$1C
Reserved
-
$1D
Reserved
-
$1E
Reserved
-
$1F
Reserved
-
$20
MCDC0 (high byte)
RW
$21
MCDC0 (low byte)
RW
$22
MCDC1 (high byte)
RW
MC9S12XHZ512 Data Sheet, Rev. 1.06
434
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Table 11-2. MC10B12C - Memory Map
$23
MCDC1 (low byte)
RW
$24
MCDC2 (high byte)
RW
$25
MCDC2 (low byte)
RW
$26
MCDC3 (high byte)
RW
$27
MCDC3 (low byte)
RW
$28
MCDC4 (high byte)
RW
$29
MCDC4 (low byte)
RW
$2A
MCDC5 (high byte)
RW
$2B
MCDC5 (low byte)
RW
$2C
MCDC6 (high byte)
RW
$2D
MCDC6 (low byte)
RW
$2E
MCDC7 (high byte)
RW
$2F
MCDC7 (low byte)
RW
$30
MCDC8 (high byte)
RW
$31
MCDC8 (low byte)
RW
$32
MCDC9 (high byte)
RW
$33
MCDC9 (low byte)
RW
$34
MCDC10 (high byte)
RW
$35
MCDC10 (low byte)
RW
$36
MCDC11 (high byte)
RW
$37
MCDC11 (low byte)
RW
$38
Reserved
-
$39
Reserved
-
$3A
Reserved
-
$3B
Reserved
-
$3C
Reserved
-
$3D
Reserved
-
$3E
Reserved
-
$3F
Reserved
-
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
435
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.3.2
11.3.2.1
Register Descriptions
Motor Controller Control Register 0
This register controls the operating mode of the motor controller module.
Offset Module Base + 0x0000
7
R
6
5
4
3
2
MCSWAI
FAST
DITH
0
0
0
0
1
0
0
MCPRE[1:0]
MCTOIF
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-3. Motor Controller Control Register 0 (MCCTL0)
Table 11-3. MCCTL0 Field Descriptions
Field
Description
6:5
MCPRE[1:0]
Motor Controller Prescaler Select — MCPRE1 and MCPRE0 determine the prescaler value that sets the
motor controller timer counter clock frequency (fTC). The clock source for the prescaler is the peripheral bus
clock (fBUS) as shown in Figure 11-22. Writes to MCPRE1 or MCPRE0 will not affect the timer counter clock
frequency fTC until the start of the next PWM period. Table 11-4 shows the prescaler values that result from
the possible combinations of MCPRE1 and MCPRE0
4
MCSWAI
3
FAST
Motor Controller PWM Resolution Mode
0 PWM operates in 11-bit resolution mode, duty cycle registers of all channels are switched to word mode.
1 PWM operates in 7-bit resolution (fast) mode, duty cycle registers of all channels are switched to byte mode.
2
DITH
Motor Control/Driver Dither Feature Enable (refer to Section 11.4.1.3.5, “Dither Bit (DITH)”)
0 Dither feature is disabled.
1 Dither feature is enabled.
0
MCTOIF
.
Motor Controller Module Stop in Wait Mode
0 Entering wait mode has no effect on the motor controller module and the associated port pins maintain the
functionality they had prior to entering wait mode both during wait mode and after exiting wait mode.
1 Entering wait mode will stop the clock of the module and debias the analog circuitry. The
module will release the pins.
Motor Controller Timer Counter Overflow Interrupt Flag — This bit is set when a motor controller timer
counter overflow occurs. The bit is cleared by writing a 1 to the bit.
0 A motor controller timer counter overflow has not occurred since the last reset or since the bit was cleared.
1 A motor controller timer counter overflow has occurred.
Table 11-4. Prescaler Values
MCPRE[1:0]
fTC
00
fBus
01
fBus/2
10
fBus/4
11
fBus/8
MC9S12XHZ512 Data Sheet, Rev. 1.06
436
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.3.2.2
Motor Controller Control Register 1
This register controls the behavior of the analog section of the motor controller as well as the interrupt
enables.
Offset Module Base + 0x0001
7
R
6
5
4
3
2
1
0
0
0
0
0
0
RECIRC
0
MCTOIE
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-4. Motor Controller Control Register 1 (MCCTL1)
Table 11-5. MCCTL1 Field Descriptions
Field
Description
7
RECIRC
Recirculation in (Dual) Full H-Bridge Mode (refer to Section 11.4.1.3.3, “RECIRC Bit”)— RECIRC only
affects the outputs in (dual) full H-bridge modes. In half H-bridge mode, the PWM output is always active low.
RECIRC = 1 will also invert the effect of the S bits (refer to Section 11.4.1.3.2, “Sign Bit (S)”) in (dual) full
H-bridge modes. RECIRC must be changed only while no PWM channel is operating in (dual) full H-bridge
mode; otherwise, erroneous output pattern may occur.
0 Recirculation on the high side transistors. Active state for PWM output is logic low, the static channel will
output logic high.
1 Recirculation on the low side transistors. Active state for PWM output is logic high, the static channel will
output logic low.
0
MCTOIE
Motor Controller Timer Counter Overflow Interrupt Enable
0 Interrupt disabled.
1 Interrupt enabled. An interrupt will be generated when the motor controller timer counter overflow interrupt flag
(MCTOIF) is set.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
437
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.3.2.3
Motor Controller Period Register
The period register defines PER, the number of motor controller timer counter clocks a PWM period lasts.
The motor controller timer counter is clocked with the frequency fTC. If dither mode is enabled (DITH = 1,
refer to Section 11.4.1.3.5, “Dither Bit (DITH)”), P0 is ignored and reads as a 0. In this case
PER = 2 * D[10:1].
Offset Module Base + 0x0002, 0x0003
R
15
14
13
12
11
0
0
0
0
0
10
9
8
7
6
5
4
3
2
1
0
P10
P9
P8
P7
P6
P5
P4
P3
P2
P1
P0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-5. Motor Controller Period Register (MCPER) with DITH = 0
Offset Module Base + 0x0002, 0x0003
R
15
14
13
12
11
0
0
0
0
0
10
9
8
7
6
5
4
3
2
1
P10
P9
P8
P7
P6
P5
P4
P3
P2
P1
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-6. Motor Controller Period Register (MCPER) with DITH = 1
For example, programming MCPER to 0x0022 (PER = 34 decimal) will result in 34 counts for each
complete PWM period. Setting MCPER to 0 will shut off all PWM channels as if MCAM[1:0] is set to 0
in all channel control registers after the next period timer counter overflow. In this case, the motor
controller releases all pins.
NOTE
Programming MCPER to 0x0001 and setting the DITH bit will be managed
as if MCPER is programmed to 0x0000. All PWM channels will be shut off
after the next period timer counter overflow.
MC9S12XHZ512 Data Sheet, Rev. 1.06
438
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.3.2.4
Motor Controller Channel Control Registers
Each PWM channel has one associated control register to control output delay, PWM alignment, and
output mode. The registers are named MCCC0... MCCC11. In the following, MCCC0 is described as a
reference for all twelve registers.
Offset Module Base + 0x0010 . . . 0x001B
7
6
5
4
MCOM1
MCOM0
MCAM1
MCAM0
0
0
0
0
R
3
2
0
0
1
0
CD1
CD0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 11-7. Motor Controller Control Register Channel0
.. 11 (MCCC0 .. MCCC11)
Table 11-6. MCCC0–MCCC11 Field Descriptions
Field
Description
7:6
Output Mode — MCOM1, MCOM0 control the PWM channel’s output mode. See Table 11-7.
MCOM[1:0]
5:4
MCAM[1:0]
PWM Channel Alignment Mode — MCAM1, MCAM0 control the PWM channel’s PWM alignment mode and
operation. See Table 11-8.
MCAM[1:0] and MCOM[1:0] are double buffered. The values used for the generation of the output waveform
will be copied to the working registers either at once (if all PWM channels are disabled or MCPER is set to 0)
or if a timer counter overflow occurs. Reads of the register return the most recent written value, which are not
necessarily the currently active values.
1:0
CD[1:0]
PWM Channel Delay — Each PWM channel can be individually delayed by a programmable number of PWM
timer counter clocks. The delay will be n/fTC. See Table 11-9.
Table 11-7. Output Mode
MCOM[1:0]
Output Mode
00
Half H-bridge mode, PWM on MnCxM, MnCxP is released
01
Half H-bridge mode, PWM on MnCxP, MnCxM is released
10
Full H-bridge mode
11
Dual full H-bridge mode
Table 11-8. PWM Alignment Mode
MCAM[1:0]
PWM Alignment Mode
00
Channel disabled
01
Left aligned
10
Right aligned
11
Center aligned
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
439
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Table 11-9. Channel Delay
CD[1:0]
n [# of PWM Clocks]
00
0
01
1
10
2
11
3
NOTE
The PWM motor controller will release the pins after the next PWM timer
counter overflow without accommodating any channel delay if a single
channel has been disabled or if the period register has been cleared or all
channels have been disabled. Program one or more inactive PWM frames
(duty cycle = 0) before writing a configuration that disables a single channel
or the entire PWM motor controller.
11.3.2.5
Motor Controller Duty Cycle Registers
Each duty cycle register sets the sign and duty functionality for the respective PWM channel.
The contents of the duty cycle registers define DUTY, the number of motor controller timer counter clocks
the corresponding output is driven low (RECIRC = 0) or is driven high (RECIRC = 1). Setting all bits to 0
will give a static high output in case of RECIRC = 0; otherwise, a static low output. Values greater than or
equal to the contents of the period register will generate a static low output in case of RECIRC = 0, or a
static high output if RECIRC = 1. The layout of the duty cycle registers differ dependent upon the state of
the FAST bit in the control register 0.
Offset Module Base + 0x0020 . . . 0x0037
15
R
14
13
12
11
S
S
S
S
S
Access: User read/write
10
9
8
7
6
5
4
3
2
1
0
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-8. Motor Controller Duty Cycle Register x (MCDCx) with FAST = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
440
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Offset Module Base + 0x0020 . . . 0x0037
Access: User read/write
15
14
13
12
11
10
9
8
S
D8
D7
D6
D5
D4
D3
D2
0
0
0
0
0
0
0
0
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 11-9. Motor Controller Duty Cycle Register x (MCDCx) with FAST = 1
Table 11-10. MCDCx Field Descriptions
Field
Description
0
S
SIGN — The SIGN bit is used to define which output will drive the PWM signal in (dual) full-H-bridge modes. The
SIGN bit has no effect in half-bridge modes. See Section 11.4.1.3.2, “Sign Bit (S)”, and table Table 11-12 for
detailed information about the impact of RECIRC and SIGN bit on the PWM output.
Whenever FAST = 1, the bits D10, D9, D1, and D0 will be set to 0 if the duty cycle register is written.
For example setting MCDCx = 0x0158 with FAST = 0 gives the same output waveform as setting
MCDCx = 0x5600 with FAST = 1 (with FAST = 1, the low byte of MCDCx needs not to be written).
The state of the FAST bit has impact only during write and read operations. A change of the FAST bit (set
or clear) without writing a new value does not impact the internal interpretation of the duty cycle values.
To prevent the output from inconsistent signals, the duty cycle registers are double buffered. The motor
controller module will use working registers to generate the output signals. The working registers are
copied from the bus accessible registers at the following conditions:
• MCPER is set to 0 (all channels are disabled in this case)
• MCAM[1:0] of the respective channel is set to 0 (channel is disabled)
• A PWM timer counter overflow occurs while in half H-bridge or full H-bridge mode
• A PWM channel pair is configured to work in Dual Full H-Bridge mode and a PWM timer counter
overflow occurs after the odd1 duty cycle register of the channel pair has been written.
In this way, the output of the PWM will always be either the old PWM waveform or the new PWM
waveform, not some variation in between.
Reads of this register return the most recent value written. Reads do not necessarily return the value of the
currently active sign, duty cycle, and dither functionality due to the double buffering scheme.
1. Odd duty cycle register: MCDCx+1, x = 2⋅n
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
441
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4
Functional Description
11.4.1
Modes of Operation
11.4.1.1
PWM Output Modes
The motor controller is configurable between three output modes.
• Dual full H-bridge mode can be used to control either a stepper motor or a 360° air core instrument.
In this case two PWM channels are combined.
• In full H-bridge mode, each PWM channel is updated independently.
• In half H-bridge mode, one pin of the PWM channel can generate a PWM signal to control a 90°
air core instrument (or other load requiring a PWM signal) and the other pin is unused.
The mode of operation for each PWM channel is determined by the corresponding MCOM[1:0] bits in
channel control registers. After a reset occurs, each PWM channel will be disabled, the corresponding pins
are released.
Each PWM channel consists of two pins. One output pin will generate a PWM signal. The other will
operate as logic high or low output depending on the state of the RECIRC bit (refer to Section 11.4.1.3.3,
“RECIRC Bit”), while in (dual) full H-bridge mode, or will be released, while in half H-bridge mode. The
state of the S bit in the duty cycle register determines the pin where the PWM signal is driven in full
H-bridge mode. While in half H-bridge mode, the state of the released pin is determined by other modules
associated with this pin.
Associated with each PWM channel pair n are two PWM channels, x and x + 1, where x = 2 * n and n
(0,1,2... 5) is the PWM channel pair number. Duty cycle register x controls the sign of the PWM signal
(which pin drives the PWM signal) and the duty cycle of the PWM signal for motor controller channel x.
The pins associated with PWM channel x are MnC0P and MnC0M. Similarly, duty cycle register x + 1
controls the sign of the PWM signal and the duty cycle of the PWM signal for channel x + 1. The pins
associated with PWM channel x + 1 are MnC1P and MnC1M. This is summarized in Table 11-11.
Table 11-11. Corresponding Registers and Pin Names for each PWM Channel Pair
PWM Channel
Pair Number
PWM
Channel
Control
Register
Duty Cycle Register
Channel Number
MCMCx
MCDCx
PWM Channel x, x = 2⋅n
MCMCx+1
MCDCx+1
PWM Channel x+1, x = 2⋅n
n
Pin
Names
MnC0M
MnC0P
MnC1M
MnC1P
M0C0M
MCMC0
MCDC0
PWM Channel 0
MCMC1
MCDC1
PWM Channel 1
0
M0C0P
M0C1M
M0C1P
MC9S12XHZ512 Data Sheet, Rev. 1.06
442
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Table 11-11. Corresponding Registers and Pin Names for each PWM Channel Pair
PWM Channel
Pair Number
PWM
Channel
Control
Register
Duty Cycle Register
Channel Number
MCMC2
MCDC2
PWM Channel 2
MCMC3
MCDC3
PWM Channel 3
Pin
Names
M1C0M
1
M1C0P
M1C1M
M1C1P
M2C0M
MCMC4
MCDC4
PWM Channel 4
MCMC5
MCDC5
PWM Channel 5
2
M2C0P
M2C1M
M2C1P
M3C0M
MCMC6
MCDC6
PWM Channel 6
MCMC7
MCDC7
PWM Channel 7
3
M3C0P
M3C1M
M3C1P
M4C0M
MCMC8
MCDC8
PWM Channel 8
MCMC9
MCDC9
PWM Channel 9
4
M4C0P
M4C1M
M4C1P
M5C0M
MCMC10
MCDC10
PWM Channel 10
MCMC11
MCDC11
PWM Channel 11
5
M5C0P
M5C1M
11.4.1.1.1
M5C1P
Dual Full H-Bridge Mode (MCOM = 11)
PWM channel pairs x and x + 1 operate in dual full H-bridge mode if both channels have been enabled
(MCAM[1:0]=01, 10, or 11) and both of the corresponding output mode bits MCOM[1:0] in both PWM
channel control registers are set.
A typical configuration in dual full H-bridge mode is shown in Figure 11-10. PWM channel x drives the
PWM output signal on either MnC0P or MnC0M. If MnC0P drives the PWM signal, MnC0M will be
output either high or low depending on the RECIRC bit. If MnC0M drives the PWM signal, MnC0P will
be an output high or low. PWM channel x + 1 drives the PWM output signal on either MnC1P or MnC1M.
If MnC1P drives the PWM signal, MnC1M will be an output high or low. If MnC1M drives the PWM
signal, MnC1P will be an output high or low. This results in motor recirculation currents on the high side
drivers (RECIRC = 0) while the PWM signal is at a logic high level, or motor recirculation currents on the
low side drivers (RECIRC = 1) while the PWM signal is at a logic low level. The pin driving the PWM
signal is determined by the S (sign) bit in the corresponding duty cycle register and the state of the
RECIRC bit. The value of the PWM duty cycle is determined by the value of the D[10:0] or D[8:2] bits
respectively in the duty cycle register depending on the state of the FAST bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
443
Chapter 11 Motor Controller (MC10B12CV2) Block Description
PWM Channel x
MnC0P
MnC0M
Motor n, Coil 0
Motor n, Coil 1
PWM Channel x + 1
MnC1P
MnC1M
Figure 11-10. Typical Dual Full H-Bridge Mode Configuration
Whenever FAST = 0 only 16-bit write accesses to the duty cycle registers are allowed, 8-bit write accesses
can lead to unpredictable duty cycles.
While fast mode is enabled (FAST = 1), 8-bit write accesses to the high byte of the duty cycle registers are
allowed, because only the high byte of the duty cycle register is used to determine the duty cycle.
The following sequence should be used to update the current magnitude and direction for coil 0 and coil 1
of the motor to achieve consistent PWM output:
1. Write to duty cycle register x
2. Write to duty cycle register x + 1.
At the next timer counter overflow, the duty cycle registers will be copied to the working duty cycle
registers. Sequential writes to the duty cycle register x will result in the previous data being overwritten.
11.4.1.1.2
Full H-Bridge Mode (MCOM = 10)
In full H-bridge mode, the PWM channels x and x + 1 operate independently. The duty cycle working
registers are updated whenever a timer counter overflow occurs.
11.4.1.1.3
Half H-Bridge Mode (MCOM = 00 or 01)
In half H-bridge mode, the PWM channels x and x + 1 operate independently. In this mode, each PWM
channel can be configured such that one pin is released and the other pin is a PWM output. Figure 11-11
shows a typical configuration in half H-bridge mode.
The two pins associated with each channel are switchable between released mode and PWM output
dependent upon the state of the MCOM[1:0] bits in the MCCCx (channel control) register. See register
description in Section 11.3.2.4, “Motor Controller Channel Control Registers”. In half H-bridge mode, the
state of the S bit has no effect.
MC9S12XHZ512 Data Sheet, Rev. 1.06
444
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
VDDM
Released
MnC0P
MnC0M
PWM Channel x
PWM Output
VDDM
VSSM
Released
PWM Channel x + 1
MnC1P
MnC1M
PWM Output
VSSM
Figure 11-11. Typical Quad Half H-Bridge Mode Configuration
11.4.1.2
Relationship Between PWM Mode and PWM Channel Enable
The pair of motor controller channels cannot be placed into dual full H-bridge mode unless both motor
controller channels have been enabled (MCAM[1:0] not equal to 00) and dual full H-bridge mode is
selected for both PWM channels (MCOM[1:0] = 11). If only one channel is set to dual full H-bridge mode,
this channel will operate in full H-bridge mode, the other as programmed.
11.4.1.3
11.4.1.3.1
Relationship Between Sign, Duty, Dither, RECIRC, Period,
and PWM Mode Functions
PWM Alignment Modes
Each PWM channel can be programmed individually to three different alignment modes. The mode is
determined by the MCAM[1:0] bits in the corresponding channel control register.
Left aligned (MCAM[1:0] = 01): The output will start active (low if RECIRC = 0 or high if RECIRC = 1)
and will turn inactive (high if RECIRC = 0 or low if RECIRC = 1) after the number of counts specified by
the corresponding duty cycle register.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
445
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
99 0
15
15
99 0
PWM Output
1 Period
1 Period
100 Counts
100 Counts
DITH = 0, MCAM[1:0] = 01, MCDCx = 15, MCPER = 100, RECIRC = 0
Right aligned (MCAM[1:0] = 10): The output will start inactive (high if RECIRC = 0 and low if
RECIRC = 1) and will turn active after the number of counts specified by the difference of the contents of
period register and the corresponding duty cycle register.
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
85
99 0
85
99 0
PWM Output
1 Period
1 Period
100 Counts
100 Counts
DITH = 0, MCAM[1:0] = 10, MCDCx = 15, MCPER = 100, RECIRC = 0
Center aligned (MCAM[1:0] = 11): Even periods will be output left aligned, odd periods will be output
right aligned. PWM operation starts with the even period after the channel has been enabled. PWM
operation in center aligned mode might start with the odd period if the channel has not been disabled before
changing the alignment mode to center aligned.
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
99 0
15
85
99 0
PWM Output
1 Period
1 Period
100 Counts
100 Counts
DITH = 0, MCAM[1:0] = 11, MCDCx = 15, MCPER = 100, RECIRC = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
446
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4.1.3.2
Sign Bit (S)
Assuming RECIRC = 0 (the active state of the PWM signal is low), when the S bit for the corresponding
channel is cleared, MnC0P (if the PWM channel number is even, n = 0, 1, 2...5, see Table 11-11) or MnC1P
(if the PWM channel number is odd, ,n = 0, 1, 2...5 see Table 11-11), outputs a logic high while in (dual)
full H-bridge mode. In half H-bridge mode the state of the S bit has no effect. The PWM output signal is
generated on MnC0M (if the PWM channel number is even, n = 0, 1, 2...5, see Table 11-11) or MnC1M
(if the PWM channel number is odd, n = 0, 1, 2...5).
Assuming RECIRC = 0 (the active state of the PWM signal is low), when the S bit for the corresponding
channel is set, MnC0M (if the PWM channel number is even, n = 0, 1, 2...5, see Table 11-11) or MnC1M
(if the PWM channel number is odd, n = 0, 1, 2...5, see Table 11-11), outputs a logic high while in (dual)
full H-bridge mode. In half H-bridge mode the state of the S bit has no effect. The PWM output signal is
generated on MnC0P (if the PWM channel number is even, n = 0, 1, 2...5, see Table 11-11) or MnC1P (if
the PWM channel number is odd, n = 0, 1, 2...5).
Setting RECIRC = 1 will also invert the effect of the S bit such that while S = 0, MnC0P or MnC1P will
generate the PWM signal and MnC0M or MnC1M will be a static low output. While S = 1, MnC0M or
MnC1M will generate the PWM signal and MnC0P or MnC1P will be a static low output. In this case the
active state of the PWM signal will be high.
See Table 11-12 for detailed information about the impact of SIGN and RECIRC bit on the PWM output.
Table 11-12. Impact of RECIRC and SIGN Bit on the PWM Output
Output Mode
RECIRC
SIGN
MnCyM
MnCyP
1
(Dual) Full H-Bridge
0
0
PWM1
(Dual) Full H-Bridge
0
1
1
PWM
(Dual) Full H-Bridge
1
0
0
PWM2
(Dual) Full H-Bridge
1
1
PWM
1
Half H-Bridge: PWM on MnCyM
Don’t care
Don’t care
PWM
—3
Half H-Bridge: PWM on MnCyP
Don’t care
Don’t care
—
PWM
1
PWM: The PWM signal is low active. e.g., the waveform starts with 0 in left aligned mode. Output M generates the PWM signal.
Output P is static high.
2
PWM: The PWM signal is high active. e.g., the waveform starts with 1 in left aligned mode. output P generates the PWM signal.
Output M is static low.
3 The state of the output transistors is not controlled by the motor controller.
11.4.1.3.3
RECIRC Bit
The RECIRC bit controls the flow of the recirculation current of the load. Setting RECIRC = 0 will cause
recirculation current to flow through the high side transistors, and RECIRC = 1 will cause the recirculation
current to flow through the low side transistors. The RECIRC bit is only active in (dual) full H-bridge
modes.
Effectively, RECIRC = 0 will cause a static high output on the output terminal not driven by the PWM,
RECIRC = 1 will cause a static low output on the output terminals not driven by the PWM. To achieve the
same current direction, the S bit behavior is inverted if RECIRC = 1. Figure 11-12, Figure 11-13,
Figure 11-14, and Figure 11-15 illustrate the effect of the RECIRC bit in (dual) full H-bridge modes.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
447
Chapter 11 Motor Controller (MC10B12CV2) Block Description
RECIRC bit must be changed only while no PWM channel is operated in (dual) full H-bridge mode.
VDDM
Static 0
PWM 1
MnC0P
MnC0M
Static 0
PWM 1
VSSM
Figure 11-12. PWM Active Phase, RECIRC = 0, S = 0
VDDM
Static 0
PWM 0
MnC0P
MnC0M
Static 0
PWM 0
VSSM
Figure 11-13. PWM Passive Phase, RECIRC = 0, S = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
448
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
VDDM
Static 1
PWM 0
MnC0P
MnC0M
Static 1
PWM 0
VSSM
Figure 11-14. PWM Active Phase, RECIRC = 1, S = 0
VDDM
Static 1
PWM 1
MnC0P
MnC0M
PWM 1
Static 1
VSSM
Figure 11-15. PWM Passive Phase, RECIRC = 1, S = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
449
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4.1.3.4
Relationship Between RECIRC Bit, S Bit, MCOM Bits, PWM State, and Output
Transistors
Please refer to Figure 11-16 for the output transistor assignment.
VDDM
T3
T1
MnCyP
MnCyM
T2
T4
VSSM
Figure 11-16. Output Transistor Assignment
Table 11-13 illustrates the state of the output transistors in different states of the PWM motor controller
module. ‘—’ means that the state of the output transistor is not controlled by the motor controller.
Table 11-13. State of Output Transistors in Various Modes
Mode
MCOM[1:0]
PWM Duty
RECIRC
S
T1
T2
T3
T4
Off
Don’t care
—
Don’t care
Don’t care
—
—
—
—
Half H-Bridge
00
Active
Don’t care
Don’t care
—
—
OFF
ON
Half H-Bridge
00
Passive
Don’t care
Don’t care
—
—
ON
OFF
Half H-Bridge
01
Active
Don’t care
Don’t care
OFF
ON
—
—
Half H-Bridge
01
Passive
Don’t care
Don’t care
ON
OFF
—
—
(Dual) Full
10 or 11
Active
0
0
ON
OFF
OFF
ON
(Dual) Full
10 or 11
Passive
0
0
ON
OFF
ON
OFF
(Dual) Full
10 or 11
Active
0
1
OFF
ON
ON
OFF
(Dual) Full
10 or 11
Passive
0
1
ON
OFF
ON
OFF
(Dual) Full
10 or 11
Active
1
0
ON
OFF
OFF
ON
(Dual) Full
10 or 11
Passive
1
0
OFF
ON
OFF
ON
(Dual) Full
10 or 11
Active
1
1
OFF
ON
ON
OFF
(Dual) Full
10 or 11
Passive
1
1
OFF
ON
OFF
ON
MC9S12XHZ512 Data Sheet, Rev. 1.06
450
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4.1.3.5
Dither Bit (DITH)
The purpose of the dither mode is to increase the minimum length of output pulses without decreasing the
PWM resolution, in order to limit the pulse distortion introduced by the slew rate control of the outputs. If
dither mode is selected the output pattern will repeat after two timer counter overflows. For the same output
frequency, the shortest output pulse will have twice the length while dither feature is selected. To achieve
the same output frame frequency, the prescaler of the MC10B12C module has to be set to twice the
division rate if dither mode is selected; e.g., with the same prescaler division rate the repeat rate of the
output pattern is the same as well as the shortest output pulse with or without dither mode selected.
The DITH bit in control register 0 enables or disables the dither function.
DITH = 0: dither function is disabled.
When DITH is cleared and assuming left aligned operation and RECIRC = 0, the PWM output will start
at a logic low level at the beginning of the PWM period (motor controller timer counter = 0x000). The
PWM output remains low until the motor controller timer counter matches the 11-bit PWM duty cycle
value, DUTY, contained in D[10:0] in MCDCx. When a match (output compare between motor controller
timer counter and DUTY) occurs, the PWM output will toggle to a logic high level and will remain at a
logic high level until the motor controller timer counter overflows (reaches the contents of MCPER – 1).
After the motor controller timer counter resets to 0x000, the PWM output will return to a logic low level.
This completes one PWM period. The PWM period repeats every P counts (as defined by the bits P[10:0]
in the motor controller period register) of the motor controller timer counter. If DUTY >= P, the output
will be static low. If DUTY = 0x0000, the output will be continuously at a logic high level. The relationship
between the motor controller timer counter clock, motor controller timer counter value, and PWM output
while DITH = 0 is shown in Figure 11-17.
Motor Controller
Timer Counter Clock
Motor Controller
Timer Counter
0
100
199 0
100
199 0
PWM Output
1 Period
200 Counts
1 Period
200 Counts
Figure 11-17. PWM Output: DITH = 0, MCAM[1:0] = 01, MCDC = 100,
MCPER = 200, RECIRC = 0
DITH = 1: dither function is enabled
Please note if DITH = 1, the bit P0 in the motor controller period register will be internally forced to 0 and
read always as 0.
When DITH is set and assuming left aligned operation and RECIRC = 0, the PWM output will start at a
logic low level at the beginning of the PWM period (when the motor controller timer counter = 0x000).
The PWM output remains low until the motor controller timer counter matches the 10-bit PWM duty cycle
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
451
Chapter 11 Motor Controller (MC10B12CV2) Block Description
value, DUTY, contained in D[10:1] in MCDCx. When a match (output compare between motor controller
timer counter and DUTY) occurs, the PWM output will toggle to a logic high level and will remain at a
logic high level until the motor controller timer counter overflows (reaches the value defined by P[10:1] – 1
in MCPER). After the motor controller timer counter resets to 0x000, the PWM output will return to a logic
low level. This completes the first half of the PWM period. During the second half of the PWM period, the
PWM output will remain at a logic low level until either the motor controller timer counter matches the
10-bit PWM duty cycle value, DUTY, contained in D[10:1] in MCDCx if D0 = 0, or the motor controller
timer counter matches the 10-bit PWM duty cycle value + 1 (the value of D[10:1] in MCDCx is increment
by 1 and is compared with the motor controller timer counter value) if D0 = 1 in the corresponding duty
cycle register. When a match occurs, the PWM output will toggle to a logic high level and will remain at
a logic high level until the motor controller timer counter overflows (reaches the value defined by P[10:1]
– 1 in MCPER). After the motor controller timer counter resets to 0x000, the PWM output will return to
a logic low level.
This process will repeat every number of counts of the motor controller timer counter defined by the period
register contents (P[10:0]). If the output is neither set to 0% nor to 100% there will be four edges on the
PWM output per PWM period in this case. Therefore, the PWM output compare function will alternate
between DUTY and DUTY + 1 every half PWM period if D0 in the corresponding duty cycle register is
set to 1. The relationship between the motor controller timer counter clock (fTC), motor controller timer
counter value, and left aligned PWM output if DITH = 1 is shown in Figure 11-18 and Figure 11-19.
Figure 11-20 and Figure 11-21 show right aligned and center aligned PWM operation respectively, with
dither feature enabled and D0 = 1. Please note: In the following examples, the MCPER value is defined by
the bits P[10:0], which is, if DITH = 1, always an even number.
NOTE
The DITH bit must be changed only if the motor controller is disabled (all
channels disabled or period register cleared) to avoid erroneous waveforms.
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
15
16
99 0
15
16
99 0
PWM Output
1 Period
100 Counts
100 Counts
Figure 11-18. PWM Output: DITH = 1, MCAM[1:0] = 01, MCDC = 31, MCPER = 200, RECIRC = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
452
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
Motor Controller
Timer Counter
Clock
Motor Controller
Timer Counter
0
16
15
99 0
15
16
99 0
PWM Output
1 Period
100 Counts
100 Counts
Figure 11-19. PWM Output: DITH = 1, MCAM[1:0] = 01, MCDC = 30, MCPER = 200, RECIRC = 0
.
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
84
85
99 0
84
85
99 0
PWM Output
1 Period
100 Counts
100 Counts
Figure 11-20. PWM Output: DITH = 1, MCAM[1:0] = 10, MCDC = 31, MCPER = 200, RECIRC = 0
Motor Controller
Timer Counter
Clock
Motor Controller
0
Timer Counter
99 0
15
84
99 0
PWM Output
1 Period
100 Counts
100 Counts
Figure 11-21. PWM Output: DITH = 1, MCAM[1:0] = 11, MCDC = 31, MCPER = 200, RECIRC = 0
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
453
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4.2
PWM Duty Cycle
The PWM duty cycle for the motor controller channel x can be determined by dividing the decimal
representation of bits D[10:0] in MCDCx by the decimal representation of the bits P[10:0] in MCPER and
multiplying the result by 100% as shown in the equation below:
DUTY
Effective PWM Channel X % Duty Cycle = --------------------- ⋅ 100%
MCPER
NOTE
x = PWM Channel Number = 0, 1, 2, 3 ... 11. This equation is only valid if
DUTY <= MCPER and MCPER is not equal to 0.
Whenever D[10:0] >= P[10:0], a constant low level (RECIRC = 0) or high level (RECIRC = 1) will be
output.
11.4.3
Motor Controller Counter Clock Source
Figure 11-22 shows how the PWM motor controller timer counter clock source is selected.
Clock
Generator
Clocks and
Reset
Generator
Module
CLK
Peripheral
Bus
Clock fBUS
Motor Controller
Timer
Counter Clock
Prescaler Select
MPPRE0, MPPRE1
1
1/2
1/4
1/8
Motor Controller Timer
Counter Clock fTC
11-Bit Motor Controller
Timer Counter
Motor Controller Timer
Counter Prescaler
Figure 11-22. Motor Controller Counter Clock Selection
The peripheral bus clock is the source for the motor controller counter prescaler. The motor controller
counter clock rate, fTC, is set by selecting the appropriate prescaler value. The prescaler is selected with
the MCPRE[1:0] bits in motor controller control register 0 (MCCTL0). The motor controller channel
frequency of operation can be calculated using the following formula if DITH = 0:
fTC
Motor Channel Frequency (Hz) = -----------------------------MCPER ⋅ M
MC9S12XHZ512 Data Sheet, Rev. 1.06
454
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
The motor controller channel frequency of operation can be calculated using the following formula if
DITH = 1:
fTC
Motor Channel Frequency (Hz) = ------------------------------------MCPER ⋅ M ⁄ 2
NOTE
Both equations are only valid if MCPER is not equal to 0. M = 1 for left or
right aligned mode, M = 2 for center aligned mode.
Table 11-14 shows examples of the motor controller channel frequencies that can be generated based on
different peripheral bus clock frequencies and the prescaler value.
Table 11-14. Motor Controller Channel Frequencies (Hz),
MCPER = 256, DITH = 0, MCAM = 10, 01
Peripheral Bus Clock Frequency
Prescaler
16 MHz
10 MHz
8 MHz
5 MHz
4 MHz
1
62500
39063
31250
19531
15625
1/2
31250
19531
15625
9766
7813
1/4
15625
9766
7813
4883
3906
1/8
7813
4883
3906
2441
1953
NOTE
Due to the selectable slew rate control of the outputs, clipping may occur on
short output pulses.
11.4.4
Output Switching Delay
In order to prevent large peak current draw from the motor power supply, selectable delays can be used to
stagger the high logic level to low logic level transitions on the motor controller outputs. The timing delay,
td, is determined by the CD[1:0] bits in the corresponding channel control register (MCMCx) and is
selectable between 0, 1, 2, or 3 motor controller timer counter clock cycles.
NOTE
A PWM channel gets disabled at the next timer counter overflow without
notice of the switching delay.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
455
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.4.5
Operation in Wait Mode
During wait mode, the operation of the motor controller pins are selectable between the following two
options:
1. MCSWAI = 1: All module clocks are stopped and the associated port pins are set to their inactive
state, which is defined by the state of the RECIRC bit during wait mode. The motor controller
module registers stay the same as they were prior to entering wait mode. Therefore, after exiting
from wait mode, the associated port pins will resume to the same functionality they had prior to
entering wait mode.
2. MCSWAI = 0: The PWM clocks continue to run and the associated port pins maintain the
functionality they had prior to entering wait mode both during wait mode and after exiting wait
mode.
11.4.6
Operation in Stop and Pseudo-Stop Modes
All module clocks are stopped and the associated port pins are set to their inactive state, which is defined
by the state of the RECIRC bit. The motor controller module registers stay the same as they were prior to
entering stop or pseudo-stop modes. Therefore, after exiting from stop or pseudo-stop modes, the
associated port pins will resume to the same functionality they had prior to entering stop or pseudo-stop
modes.
11.5
Reset
The motor controller is reset by system reset. All associated ports are released, all registers of the motor
controller module will switch to their reset state as defined in Section 11.3.2, “Register Descriptions”.
11.6
Interrupts
The motor controller has one interrupt source.
11.6.1
Timer Counter Overflow Interrupt
An interrupt will be requested when the MCTOIE bit in the motor controller control register 1 is set and
the running PWM frame is finished. The interrupt is cleared by either setting the MCTOIE bit to 0 or to
write a 1 to the MCTOIF bit in the motor controller control register 0.
MC9S12XHZ512 Data Sheet, Rev. 1.06
456
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
11.7
Initialization/Application Information
This section provides an example of how the PWM motor controller can be initialized and used by
application software. The configuration parameters (e.g., timer settings, duty cycle values, etc.) are not
guaranteed to be adequate for any real application.
The example software is implemented in assembly language.
11.7.1
Code Example
One way to use the motor controller is:
1. Perform global initialization
a) Set the motor controller control registers MCCTL0 and MCCTL1 to appropriate values.
i) Prescaler disabled (MCPRE1 = 0, MCPRE0 = 0).
ii) Fast mode and dither disabled (FAST = 0, DITH = 0).
iii) Recirculation feature in dual full H-bridge mode disabled (RECIRC = 0).
All other bits in MCCTL0 and MCCTL1 are set to 0.
b) Configure the channel control registers for the desired mode.
i) Dual full H-bridge mode (MCOM[1:0] = 11).
ii) Left aligned PWM (MCAM[1:0] = 01).
iii) No channel delay (MCCD[1:0] = 00).
2. Perform the startup phase
a) Clear the duty cycle registers MCDC0 and MCDC1
b) Initialize the period register MCPER, which is equivalent to enabling the motor controller.
c) Enable the timer which generates the timebase for the updates of the duty cycle registers.
3. Main program
a) Check if pin PB0 is set to “1” and execute the sub program if a timer interrupt is pending.
b) Initiate the shutdown procedure if pin PB0 is set to “0”.
4. Sub program
a) Update the duty cycle registers
Load the duty cycle registers MCDC0 and MCDC1 with new values from the table and clear
the timer interrupt flag.
The sub program will initiate the shutdown procedure if pin PB0 is set to “0”.
b) Shutdown procedure
The timer is disabled and the duty cycle registers are cleared to drive an inactive value on the PWM output
as long as the motor controller is enabled. The period register is cleared after a certain time, which disables
the motor controller. The table address is restored and the timer interrupt flag is cleared.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
457
Chapter 11 Motor Controller (MC10B12CV2) Block Description
;-----------------------------------------------------------------------------------------; Motor Controller (MC10B8C) setup example
;-----------------------------------------------------------------------------------------; Timer defines
;-----------------------------------------------------------------------------------------T_START
EQU $0040
TSCR1
EQU T_START+$06
TFLG2
EQU T_START+$0F
;-----------------------------------------------------------------------------------------; Motor Controller defines
;-----------------------------------------------------------------------------------------MC_START
EQU $0200
MCCTL0
EQU MC_START+$00
MCCTL1
EQU MC_START+$01
MCPER_HI
EQU MC_START+$02
MCPER_LO
EQU MC_START+$03
MCCC0
EQU MC_START+$10
MCCC1
EQU MC_START+$11
MCCC2
EQU MC_START+$12
MCCC3
EQU MC_START+$13
MCDC0_HI
EQU MC_START+$20
MCDC0_LO
EQU MC_START+$21
MCDC1_HI
EQU MC_START+$22
MCDC1_LO
EQU MC_START+$23
MCDC2_HI
EQU MC_START+$24
MCDC2_LO
EQU MC_START+$25
MCDC3_HI
EQU MC_START+$26
MCDC3_LO
EQU MC_START+$27
;-----------------------------------------------------------------------------------------; Port defines
;-----------------------------------------------------------------------------------------DDRB
EQU $0003
PORTB
EQU $0001
;-----------------------------------------------------------------------------------------; Flash defines
;-----------------------------------------------------------------------------------------FLASH_START
EQU $0100
FCMD
EQU FLASH_START+$06
FCLKDIV
EQU FLASH_START+$00
FSTAT
EQU FLASH_START+$05
FTSTMOD
EQU FLASH_START+$02
; Variables
CODE_START
EQU $1000
; start of program code
DTYDAT
EQU $1500
; start of motor controller duty cycle data
TEMP_X
EQU $1700
; save location for IX reg in ISR
TABLESIZE
EQU $1704
; number of config entries in the table
MCPERIOD
EQU $0250
; motor controller period
;-----------------------------------------------------------------------------------------;-----------------------------------------------------------------------------------------ORG
CODE_START
; start of code
LDS
#$1FFF
; set stack pointer
MOVW
#$000A,TABLESIZE
; number of configurations in the table
MOVW
TABLESIZE,TEMP_X
MC9S12XHZ512 Data Sheet, Rev. 1.06
458
Freescale Semiconductor
Chapter 11 Motor Controller (MC10B12CV2) Block Description
;-----------------------------------------------------------------------------------------;global motor controller init
;-----------------------------------------------------------------------------------------GLB_INIT: MOVB
#$0000,MCCTL0
; fMC = fBUS, FAST=0, DITH=0
MOVB
#$0000,MCCTL1
; RECIRC=0, MCTOIE=0
MOVW
#$D0D0,MCCC0
; dual full h-bridge mode, left aligned,
; no channel delay
MOVW
#$0000,MCPER_HI
; disable motor controller
;-----------------------------------------------------------------------------------------;motor controller startup
;-----------------------------------------------------------------------------------------STARTUP:
MOVW
#$0000,MCDC0_HI
; define startup duty cycles
MOVW
#$0000,MCDC1_HI
MOVW
#MCPERIOD,MCPER_HI
; define PWM period
MOVB
#$80,TSCR1
; enable timer
MAIN:
LDAA
PORTB
; if PB=0, activate shutdown
ANDA
#$01
BEQ
MN0
JSR
TIM_SR
MN0:
TST
TFLG2
; poll for timer counter overflow flag
BEQ
MAIN
; TOF set?
JSR
TIM_SR
; yes, go to TIM_SR
BRA
MAIN
TIM_SR:
LDX
TEMP_X
; restore index register X
LDAA
PORTB
; if PB=0, enter shutdown routine
ANDA
#$01
BNE
SHUTDOWN
LDX
TEMP_X
; restore index register X
BEQ
NEW_SEQ
; all mc configurations done?
NEW_CFG: LDD
DTYDAT,X
; load new config’s
STD
MCDC0_HI
DEX
DEX
LDD
DTYDAT,X
STD
MCDC1_HI
BRA
END_SR
; leave sub-routine
SHUTDOWN: MOVB
#$00,TSCR1
; disable timer
MOVW
#$0000,MCDC0_HI
; define startup duty cycle
MOVW
#$0000,MCDC1_HI
; define startup duty cycle
LDAA
#$0000
; ensure that duty cycle registers are
; cleared for some time before disabling
; the motor controller
LOOP
DECA
BNE
LOOP
MOVW
#$0000,MCPER_HI
; define pwm period
NEW_SEQ: MOVW
TABLESIZE,TEMP_X
; start new tx loop
LDX
TEMP_X
END_SR:
STX
TEMP_X
; save byte counter
MOVB
#$80,TFLG2
; clear TOF
RTS
; wait for new timer overflow
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
459
Chapter 11 Motor Controller (MC10B12CV2) Block Description
;-----------------------------------------------------------------------------------------; motor controller duty cycles
;-----------------------------------------------------------------------------------------org
DTYDAT
DC.B
$02, $FF1; MCDC1_HI, MCDC1_LO
DC.B
$02, $D0 ; MCDC0_HI, MCDC0_LO
DC.B
$02, $A0 ; MCDC1_HI, MCDC1_LO
DC.B
$02, $90 ; MCDC0_HI, MCDC0_LO
DC.B
$02, $60 ; MCDC1_HI, MCDC1_LO
DC.B
$02, $25 ; MCDC0_HI, MCDC0_LO
1. The values for the duty cycle table have to be defined for the needs of the target application.
MC9S12XHZ512 Data Sheet, Rev. 1.06
460
Freescale Semiconductor
Chapter 12
Stepper Stall Detector (SSDV1) Block Description
12.1
Introduction
The stepper stall detector (SSD) block provides a circuit to measure and integrate the induced voltage on
the non-driven coil of a stepper motor using full steps when the gauge pointer is returning to zero (RTZ).
During the RTZ event, the pointer is returned to zero using full steps in either clockwise or counter
clockwise direction, where only one coil is driven at any point in time. The back electromotive force
(EMF) signal present on the non-driven coil is integrated after a blanking time, and its results stored in a
16-bit accumulator. The 16-bit modulus down counter can be used to monitor the blanking time and the
integration time. The value in the accumulator represents the change in linked flux (magnetic flux times
the number of turns in the coil) and can be compared to a stored threshold. Values above the threshold
indicate a moving motor, in which case the pointer can be advanced another full step in the same direction
and integration be repeated. Values below the threshold indicate a stalled motor, thereby marking the
cessation of the RTZ event. The SSD is capable of multiplexing two stepper motors.
12.1.1
•
•
Return to zero modes
— Blanking with no drive
— Blanking with drive
— Conversion
— Integration
Low-power modes
12.1.2
•
•
•
•
•
•
Modes of Operation
Features
Programmable full step state
Programmable integration polarity
Blanking (recirculation) state
16-bit integration accumulator register
16-bit modulus down counter with interrupt
Multiplex two stepper motors
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
461
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.1.3
Block Diagram
Coil COSx
x = A or B
Coil SINx
VDDM
T3
T1
S1
S3
S2
S4
P
A
D
P
A
D
VSSM
T7
SINxP
SINxM
S5
S7
S6
S8
T6
T4
T2
VDDM
T5
COSxM
COSxP
P
A
D
VDDM
VDDM
T8
VSSM
VSSM
P
A
D
VSSM
reference
integrator
DAC
C1
R1
–
–
+
16-bit accumulator
register
DFF
VDDM
+
R2
16-bit load
register
R2
sigma-delta converter
(analog)
VSSM
4:1 MUX
Bus Clock
1/8
1/2
1/2
1/2
2:1 MUX
16-bit modulus
down counter
1/8
Figure 12-1. SSD Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
462
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.2
External Signal Description
Each SSD signal is the output pin of a half bridge, designed to source or sink current. The H-bridge pins
drive the sine and cosine coils of a stepper motor to provide four-quadrant operation. The SSD is capable
of multiplexing between stepper motor A and stepper motor B if two motors are connected.
Table 12-1. Pin Table1
1
12.2.1
Pin Name
Node
Coil
COSxM
Minus
COSx
COSxP
Plus
SINxM
Minus
SINxP
Plus
SINx
x = A or B indicating motor A or motor B
COSxM/COSxP — Cosine Coil Pins for Motor x
These pins interface to the cosine coils of a stepper motor to measure the back EMF for calibration of the
pointer reset position.
12.2.2
SINxM/SINxP — Sine Coil Pins for Motor x
These pins interface to the sine coils of a stepper motor to measure the back EMF for calibration of the
pointer reset position.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
463
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.3
Memory Map and Register Definition
This section provides a detailed description of all registers of the stepper stall detector (SSD) block.
12.3.1
Module Memory Map
Table 12-2 gives an overview of all registers in the SSDV1 memory map. The SSDV1 occupies eight bytes
in the memory space. The register address results from the addition of base address and address offset. The
base address is determined at the MCU level and is given in the Device Overview chapter. The address
offset is defined at the block level and is given here.
Table 12-2. SSDV1 Memory Map
Address
Offset
12.3.2
Use
Access
0x0000
RTZCTL
R/W
0x0001
MDCCTL
R/W
0x0002
SSDCTL
R/W
0x0003
SSDFLG
R/W
0x0004
MDCCNT (High)
R/W
0x0005
MDCCNT (Low)
R/W
0x0006
ITGACC (High)
R
0x0007
ITGACC (Low)
R
Register Descriptions
This section describes in detail all the registers and register bits in the SSDV1 block. Each description
includes a standard register diagram with an associated figure number. Details of register bit and field
function follow the register diagrams, in bit order.
MC9S12XHZ512 Data Sheet, Rev. 1.06
464
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.3.2.1
Return-to-Zero Control Register (RTZCTL)
Module Base + 0x0000
7
6
5
4
ITG
DCOIL
RCIR
POL
0
0
0
0
R
3
2
1
0
0
SMS
STEP
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 12-2. Return-to-Zero Control Register (RTZCTL)
Read: anytime
Write: anytime
Table 12-3. RTZCTL Field Descriptions
Field
Description
7
ITG
Integration — During return to zero (RTZE = 1), one of the coils must be recirculated or non-driven determined
by the STEP field. If the ITG bit is set, the coil is non-driven, and if the ITG bit is clear, the coil is being recirculated.
Table 12-4 shows the condition state of each transistor from Figure 12-1 based on the STEP, ITG, DCOIL and
RCIR bits.
Regardless of the RTZE bit value, if the ITG bit is set, one end of the non-driven coil connects to the (non-zero)
reference input and the other end connects to the integrator input of the sigma-delta converter. Regardless of
the RTZE bit value, if the ITG bit is clear, the non-driven coil is in a blanking state, the converter is in a reset state,
and the accumulator is initialized to zero. Table 12-5 shows the condition state of each switch from Figure 12-1
based on the ITG, STEP and POL bits.
0 Blanking
1 Integration
6
DCOIL
Drive Coil — During return to zero (RTZE=1), one of the coils must be driven determined by the STEP field. If
the DCOIL bit is set, this coil is driven. If the DCOIL bit is clear, this coil is disconnected or drivers turned off.
Table 12-4 shows the condition state of each transistor from Figure 12-1 based on the STEP, ITG, DCOIL and
RCIR bits.
0 Disconnect Coil
1 Drive Coil
5
RCIR
Recirculation in Blanking Mode — During return to zero (RTZE = 1), one of the coils is recirculated prior to
integration during the blanking period. This bit determines if the coil is recirculated via VDDM or via VSSM.
Table 12-4 shows the condition state of each transistor from Figure 12-1 based on the STEP, ITG, DCOIL and
RCIR bits.
0 Recirculation on the high side transistors
1 Recirculation on the low side transistors
4
POL
Polarity — This bit determines which end of the non-driven coil is routed to the sigma-delta converter during
conversion or integration mode. Table 12-5 shows the condition state of each switch from Figure 12-1 based on
the ITG, STEP and POL bits.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
465
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
Table 12-3. RTZCTL Field Descriptions (continued)
Field
Description
2
SMS
Stepper Motor Select — This bit selects one of two possible stepper motors to be used for stall detection. See
top level chip description for the stepper motor assignments to the SSD.
0 Stepper Motor A is selected for stall detection
1 Stepper Motor B is selected for stall detection
1:0
STEP
Full Step State — This field indicates one of the four possible full step states. Step 0 is considered the east pole
or 0° angle, step 1 is the north Pole or 90° angle, step 2 is the west pole or 180° angle, and step 3 is the south
pole or 270° angle. For each full step state, Table 12-6 shows the current through each of the two coils, and the
coil nodes that are multiplexed to the sigma-delta converter during conversion or integration mode.
Table 12-4. Transistor Condition States (RTZE = 1)
STEP
ITG
DCOIL
RCIR
T1
T2
T3
T4
T5
T6
T7
T8
xx
1
0
x
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
00
0
0
0
OFF
OFF
OFF
OFF
ON
OFF
ON
OFF
00
0
0
1
OFF
OFF
OFF
OFF
OFF
ON
OFF
ON
00
0
1
0
ON
OFF
OFF
ON
ON
OFF
ON
OFF
00
0
1
1
ON
OFF
OFF
ON
OFF
ON
OFF
ON
00
1
1
x
ON
OFF
OFF
ON
OFF
OFF
OFF
OFF
01
0
0
0
ON
OFF
ON
OFF
OFF
OFF
OFF
OFF
01
0
0
1
OFF
ON
OFF
ON
OFF
OFF
OFF
OFF
01
0
1
0
ON
OFF
ON
OFF
ON
OFF
OFF
ON
01
0
1
1
OFF
ON
OFF
ON
ON
OFF
OFF
ON
01
1
1
x
OFF
OFF
OFF
OFF
ON
OFF
OFF
ON
10
0
0
0
OFF
OFF
OFF
OFF
ON
OFF
ON
OFF
10
0
0
1
OFF
OFF
OFF
OFF
OFF
ON
OFF
ON
10
0
1
0
OFF
ON
ON
OFF
ON
OFF
ON
OFF
10
0
1
1
OFF
ON
ON
OFF
OFF
ON
OFF
ON
10
1
1
x
OFF
ON
ON
OFF
OFF
OFF
OFF
OFF
11
0
0
0
ON
OFF
ON
OFF
OFF
OFF
OFF
OFF
11
0
0
1
OFF
ON
OFF
ON
OFF
OFF
OFF
OFF
11
0
1
0
ON
OFF
ON
OFF
OFF
ON
ON
OFF
11
0
1
1
OFF
ON
OFF
ON
OFF
ON
ON
OFF
11
1
1
x
OFF
OFF
OFF
OFF
OFF
ON
ON
OFF
MC9S12XHZ512 Data Sheet, Rev. 1.06
466
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
Table 12-5. Switch Condition States (RTZE = 1 or 0)
ITG
STEP
POL
S1
S2
S3
S4
S5
S6
S7
S8
0
xx
x
Open
Open
Open
Open
Open
Open
Open
Open
1
00
0
Open
Open
Open
Open
Close
Open
Open
Close
1
00
1
Open
Open
Open
Open
Open
Close
Close
Open
1
01
0
Open
Close
Close
Open
Open
Open
Open
Open
1
01
1
Close
Open
Open
Close
Open
Open
Open
Open
1
10
0
Open
Open
Open
Open
Open
Close
Close
Open
1
10
1
Open
Open
Open
Open
Close
Open
Open
Close
1
11
0
Close
Open
Open
Close
Open
Open
Open
Open
1
11
1
Open
Close
Close
Open
Open
Open
Open
Open
Table 12-6. Full Step States
COSINE
Coil Current
STEP Pole
SINE
Coil Current
Angle
DCOIL = 0 DCOIL = 1 DCOIL = 0 DCOIL = 1
0
East
0°
0
+ I max
0
0
1
North
90°
0
0
0
+ I max
2
West
180°
0
– I max
0
0
3
South
270°
0
0
0
– I max
12.3.2.2
Coil Node to
Integrator input
(Close Switch)
Coil Node to
Reference input
(Close Switch)
ITG = 1
POL = 0
ITG = 1
POL = 1
ITG = 1
POL = 0
ITG = 1
POL = 1
SINxM (S8)
SINxP (S6)
SINxP (S5)
SINxM (S7)
COSxP (S2) COSxM (S4) COSxM (S3) COSxP (S1)
SINxP (S6)
SINxM (S8)
SINxM (S7)
SINxP (S5)
COSxM (S4) COSxP (S2) COSxP (S1) COSxM (S3)
Modulus Down Counter Control Register (MDCCTL)
Module Base + 0x0001
7
6
5
4
MCZIE
MODMC
RDMCL
PRE
R
2
0
W
Reset
3
1
0
0
MCEN
AOVIE
FLMC
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 12-3. Modulus Down Counter Control Register (MDCCTL)
Read: anytime
Write: anytime.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
467
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
l
Table 12-7. MDCCTL Field Descriptions
Field
Description
7
MCZIE
Modulus Counter Underflow Interrupt Enable
0 Interrupt disabled.
1 Interrupt enabled. An interrupt will be generated when the modulus counter underflow interrupt flag (MCZIF)
is set.
6
MODMC
Modulus Mode Enable
0 The modulus counter counts down from the value in the counter register and will stop at 0x0000.
1 Modulus mode is enabled. When the counter reaches 0x0000, the counter is loaded with the latest value
written to the modulus counter register.
Note: For proper operation, the MCEN bit should be cleared before modifying the MODMC bit in order to reset
the modulus counter to 0xFFFF.
5
RDMCL
Read Modulus Down-Counter Load
0 Reads of the modulus count register (MDCCNT) will return the present value of the count register.
1 Reads of the modulus count register (MDCCNT) will return the contents of the load register.
4
PRE
Prescaler
0 The modulus down counter clock frequency is the bus frequency divided by 64.
1 The modulus down counter clock frequency is the bus frequency divided by 512.
Note: A change in the prescaler division rate will not be effective until a load of the load register into the modulus
counter count register occurs.
3
FLMC
Force Load Register into the Modulus Counter Count Register — This bit always reads zero.
0 Write zero to this bit has no effect.
1 Write one into this bit loads the load register into the modulus counter count register.
2
MCEN
Modulus Down-Counter Enable
0 Modulus down-counter is disabled. The modulus counter (MDCCNT) is preset to 0xFFFF. This will prevent an
early interrupt flag when the modulus down-counter is enabled.
1 Modulus down-counter is enabled.
0
AOVIE
Accumulator Overflow Interrupt Enable
0 Interrupt disabled.
1 Interrupt enabled. An interrupt will be generated when the accumulator overflow interrupt flag (AOVIF) is set.
12.3.2.3
Stepper Stall Detector Control Register (SSDCTL)
Module Base + 0x0002
7
6
5
4
RTZE
SDCPU
SSDWAI
FTST
0
0
0
0
R
3
2
0
0
1
0
ACLKS
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 12-4. Stepper Stall Detector Control Register (SSDCTL)
Read: anytime
Write: anytime
MC9S12XHZ512 Data Sheet, Rev. 1.06
468
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
l
Table 12-8. SSDCTL Field Descriptions
Field
Description
7
RTZE
Return to Zero Enable — If this bit is set, the coils are controlled by the SSD and are configured into one of the
four full step states as shown in Table 12-6. If this bit is cleared, the coils are not controlled by the SSD.
0 RTZ is disabled.
1 RTZ is enabled.
6
SDCPU
Sigma-Delta Converter Power Up — This bit provides on/off control for the sigma-delta converter allowing
reduced MCU power consumption. Because the analog circuit is turned off when powered down, the sigma-delta
converter requires a recovery time after it is powered up.
0 Sigma-delta converter is powered down.
1 Sigma-delta converter is powered up.
5
SSDWAI
SSD Disabled during Wait Mode — When entering Wait Mode, this bit provides on/off control over the SSD
allowing reduced MCU power consumption. Because the analog circuit is turned off when powered down, the
sigma-delta converter requires a recovery time after exit from Wait Mode.
0 SSD continues to run in WAIT mode.
1 Entering WAIT mode freezes the clock to the prescaler divider, powers down the sigma-delta converter, and
if RTZE bit is set, the sine and cosine coils are recirculated via VSSM.
4
FTST
1:0
ACLKS
Factory Test — This bit is reserved for factory test and reads zero in user mode.
Accumulator Sample Frequency Select — This field sets the accumulator sample frequency by pre-scaling
the bus frequency by a factor of 8, 16, 32, or 64. A faster sample frequency can provide more accurate results
but cause the accumulator to overflow. Best results are achieved with a frequency between 500 kHz and 2 MHz.
Accumulator Sample Frequency = fBUS / (8 x 2ACLKS)
Table 12-9. Accumulator Sample Frequency
ACLKS
Frequency
fBUS = 40
MHz
fBUS = 25
MHz
fBUS = 16
MHz
0
fBUS / 8
5.00 MHz
3.12 MHz
2.00 MHz
1
fBUS / 16
2.50 MHz
1.56 MHz
1.00 MHz
2
fBUS / 32
1.25 MHz
781 kHz
500 kHz
3
fBUS / 64
625 kHz
391 kHz
250 kHz
NOTE
A change in the accumulator sample frequency will not be effective until the
ITG bit is cleared.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
469
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.3.2.4
Stepper Stall Detector Flag Register (SSDFLG)
Module Base + 0x0003
7
R
6
5
4
3
2
1
0
0
0
0
0
0
MCZIF
0
AOVIF
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 12-5. Stepper Stall Detector Flag Register (SSDFLG)
Read: anytime
Write: anytime.
l
Table 12-10. SSDFLG Field Descriptions
Field
Description
7
MCZIF
Modulus Counter Underflow Interrupt Flag — This flag is set when the modulus down-counter reaches
0x0000. If not masked (MCZIE = 1), a modulus counter underflow interrupt is pending while this flag is set. This
flag is cleared by writing a ‘1’ to the bit. A write of ‘0’ has no effect.
0
AOVIF
Accumulator Overflow Interrupt Flag — This flag is set when the Integration Accumulator has a positive or
negative overflow. If not masked (AOVIE = 1), an accumulator overflow interrupt is pending while this flag is set.
This flag is cleared by writing a ‘1’ to the bit. A write of ‘0’ has no effect.
12.3.2.5
Modulus Down-Counter Count Register (MDCCNT)
Module Base + 0x0004
15
14
13
12
11
10
9
8
1
1
1
1
R
MDCCNT
W
Reset
1
1
1
1
Figure 12-6. Modulus Down-Counter Count Register High (MDCCNT)
Module Base + 0x0005
7
6
5
4
3
2
1
0
1
1
1
1
R
MDCCNT
W
Reset
1
1
1
1
Figure 12-7. Modulus Down-Counter Count Register Low (MDCCNT)
Read: anytime
Write: anytime.
MC9S12XHZ512 Data Sheet, Rev. 1.06
470
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
NOTE
A separate read/write for high byte and low byte gives a different result than
accessing the register as a word.
If the RDMCL bit in the MDCCTL register is cleared, reads of the MDCCNT register will return the
present value of the count register. If the RDMCL bit is set, reads of the MDCCNT register will return the
contents of the load register.
With a 0x0000 write to the MDCCNT register, the modulus counter stays at zero and does not set the
MCZIF flag in the SSDFLG register.
If modulus mode is not enabled (MODMC = 0), a write to the MDCCNT register immediately updates the
load register and the counter register with the value written to it. The modulus counter will count down
from this value and will stop at 0x0000.
If modulus mode is enabled (MODMC = 1), a write to the MDCCNT register updates the load register with
the value written to it. The count register will not be updated with the new value until the next counter
underflow. The FLMC bit in the MDCCTL register can be used to immediately update the count register
with the new value if an immediate load is desired.
The modulus down counter clock frequency is the bus frequency divided by 64 or 512.
12.3.2.6
Integration Accumulator Register (ITGACC)
Module Base + 0x0006
15
14
13
12
R
11
10
9
8
0
0
0
0
ITGACC
W
Reset
0
0
0
0
Figure 12-8. Integration Accumulator Register High (ITGACC)
Module Base + 0x0007
7
6
5
4
R
3
2
1
0
0
0
0
0
ITGACC
W
Reset
0
0
0
0
Figure 12-9. Integration Accumulator Register Low (ITGACC)
Read: anytime.
Write: Never.
NOTE
A separate read for high byte and low byte gives a different result than
accessing the register as a word.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
471
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
This 16-bit field is signed and is represented in two’s complement. It indicates the change in flux while
integrating the back EMF present in the non-driven coil during a return to zero event.
When ITG is zero, the accumulator is initialized to 0x0000 and the sigma-delta converter is in a reset state.
When ITG is one, the accumulator increments or decrements depending on the sigma-delta conversion
sample. The accumulator sample frequency is determined by the ACLKS field. The accumulator freezes
at 0x7FFF on a positive overflow and freezes at 0x8000 on a negative overflow.
12.4
Functional Description
The stepper stall detector (SSD) has a simple control block to configure the H-bridge drivers of a stepper
motor in four different full step states with four available modes during a return to zero event. The SSD
has a detect circuit using a sigma-delta converter to measure and integrate changes in flux of the
de-energized winding in the stepping motor and the conversion result is accumulated in a 16-bit signed
register. The SSD also has a 16-bit modulus down counter to monitor blanking and integration times. DC
offset compensation is implemented when using the modulus down counter to monitor integration times.
12.4.1
Return to Zero Modes
There are four return to zero modes as shown in Table 12-11.
Table 12-11. Return to Zero Modes
12.4.1.1
ITG
DCOIL
Mode
0
0
Blanking with no drive
0
1
Blanking with drive
1
0
Conversion
1
1
Integration
Blanking with No Drive
In blanking mode with no drive, one of the coils is masked from the sigma-delta converter, and if RTZ is
enabled (RTZE = 1), it is set up to recirculate its current. If RTZ is enabled (RTZE = 1), the other coil is
disconnected to prevent any loss of flux change that would occur when the motor starts moving before the
end of recirculation and start of integration. In blanking mode with no drive, the accumulator is initialized
to 0x0000 and the converter is in a reset state.
12.4.1.2
Blanking with Drive
In blanking mode with drive, one of the coils is masked from the sigma-delta converter, and if RTZ is
enabled (RTZE = 1), it is set up to recirculate its current. If RTZ is enabled (RTZE = 1), the other coil is
driven. In blanking mode with drive, the accumulator is initialized to 0x0000 and the converter is in a reset
state.
MC9S12XHZ512 Data Sheet, Rev. 1.06
472
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.4.1.3
Conversion
In conversion mode, one of the coils is routed for integration with one end connected to the (non-zero)
reference input and the other end connected to the integrator input of the sigma-delta converter. If RTZ is
enabled (RTZE=1), both coils are disconnected. This mode is not useful for stall detection.
12.4.1.4
Integration
In integration mode, one of the coils is routed for integration with one end connected to the (non-zero)
reference input and the other end connected to the integrator input of the sigma-delta converter. If RTZ is
enabled (RTZE = 1), the other coil is driven. This mode is used to rectify and integrate the back EMF
produced by the coils to detect stepped rotary motion.
DC offset compensation is implemented when using the modulus down counter to monitor integration
time.
12.4.2
Full Step States
During a return to zero (RTZ) event, the stepper motor pointer requires a 90° full motor electrical step with
full amplitude pulses applied to each phase in turn. For counter clockwise rotation (CCW), the STEP value
is incremented 0, 1, 2, 3, 0 and so on, and for a clockwise rotation the STEP value is decremented 3, 2, 1,
0 and so on. Figure 12-10 shows the current level through each coil for each full step in CCW rotation
when DCOIL is set.
+ Imax
SINE COIL
CURRENT
0
_ Imax
Recirculation
+ Imax
COSINE COIL
CURRENT
0
_ Imax
0
1
2
3
Figure 12-10. Full Steps (CCW)
Figure 12-11 shows the current flow in the SINx and COSx H-bridges when STEP = 0, DCOIL = 1,
ITG = 0 and RCIR = 0.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
473
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
VDDM
VDDM
T3
T1
COSxP
COSxM
T2
T4
T7
T5
SINxP
SINxM
T6
VSSM
T8
VSSM
Figure 12-11. Current Flow when STEP = 0, DCOIL = 1, ITG = 0, RCIR = 0
Figure 12-12 shows the current flow in the SINx and COSx H-bridges when STEP = 1, DCOIL = 1,
ITG = 0 and RCIR = 1.
VDDM
VDDM
T3
T1
COSxP
COSxM
T2
T4
T7
T5
SINxP
SINxM
T6
VSSM
T8
VSSM
Figure 12-12. Current Flow when STEP = 1, DCOIL = 1, ITG = 0, RCIR = 1
Figure 12-13 shows the current flow in the SINx and COSx H-bridges when STEP = 2, DCOIL = 1 and
ITG = 1.
MC9S12XHZ512 Data Sheet, Rev. 1.06
474
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
VDDM
VDDM
T3
T1
COSxP
COSxM
T2
T4
T7
T5
SINxP
SINxM
T6
VSSM
T8
VSSM
Figure 12-13. Current flow when STEP = 2, DCOIL = 1, ITG = 1
Figure 12-14 shows the current flow in the SINx and COSx H-bridges when STEP = 3, DCOIL = 1 and
ITG = 1.
VDDM
VDDM
T3
T1
COSxP
COSxM
T2
T4
T7
T5
SINxP
SINxM
T6
VSSM
T8
VSSM
Figure 12-14. Current flow when STEP = 3, DCOIL = 1, ITG = 1
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
475
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
12.4.3
Operation in Low Power Modes
The SSD block can be configured for lower MCU power consumption in three different ways.
• Stop mode powers down the sigma-delta converter and halts clock to the modulus counter. Exit
from Stop enables the sigma-delta converter and the clock to the modulus counter but due to the
converter recovery time, the integration result should be ignored.
• Wait mode with SSDWAI bit set powers down the sigma-delta converter and halts the clock to the
modulus counter. Exit from Wait enables the sigma-delta converter and clock to the modulus
counter but due to the converter recovery time, the integration result should be ignored.
• Clearing SDCPU bit powers down the sigma-delta converter.
12.4.4
Stall Detection Flow
Figure 12-15 shows a flowchart and software setup for stall detection of a stepper motor. To control a
second stepper motor, the SMS bit must be toggled during the SSD initialization.
MC9S12XHZ512 Data Sheet, Rev. 1.06
476
Freescale Semiconductor
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
Using Motor Control module, drive pointer to within 3 full steps of
calibrated zero position.
Advance Pointer
Initialize SSD
1. Clear (or set) RCIR; clear (or set) POL; clear (or set) SMS;
2. Set MCZIE; clear MODMC; clear (or set) PRE; set MCEN.
3. Set RTZE; set SDCPU; write ACLKS (select sample frequency).
4. Store threshold value in RAM.
Start Blanking
1. Clear MCZIF.
2. Write MDCCNT with blanking time value.
3. Clear ITG; clear (or set) DCOIL; increment (or decrement) STEP for
CCW (or CW) motion.
End of
Blanking?
MDCCNT = 0x0000? or MCZIF = 1?
No
Yes
1. Clear MCZIF.
2. Write MDCCNT with integration time value.
3. Set ITG; set DCOIL.
Start Integration
End of
Integration?
MDCCNT = 0x0000? or MCZIF = 1?
No
Yes
No
Stall
Detection?
ITGACC < Threshold (RAM value)?
Yes
Disable SSD
1. Clear MCZIF.
2. Clear MCEN.
3. Clear ITG.
4. Clear RTZE; clear SDCPU.
Figure 12-15. Return-to-Zero Flowchart
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
477
Chapter 12 Stepper Stall Detector (SSDV1) Block Description
MC9S12XHZ512 Data Sheet, Rev. 1.06
478
Freescale Semiconductor
Chapter 13
Inter-Integrated Circuit (IICV3) Block Description
Table 13-1. Revision History
Revision
Number
Revision Date
V01.03
28 Jul 2006
V01.04
17 Nov 2006
13.3.1.2/13-483 - Revise Table1-5
Rev. 1.06
14 Aug 2007
13.3.1.1/13-483 - Backward compatible for IBAD bit name
13.1
Sections
Affected
Description of Changes
13.7.1.7/13-503 - Update flow-chart of interrupt routine for 10-bit address
Introduction
The inter-IC bus (IIC) is a two-wire, bidirectional serial bus that provides a simple, efficient method of data
exchange between devices. Being a two-wire device, the IIC bus minimizes the need for large numbers of
connections between devices, and eliminates the need for an address decoder.
This bus is suitable for applications requiring occasional communications over a short distance between a
number of devices. It also provides flexibility, allowing additional devices to be connected to the bus for
further expansion and system development.
The interface is designed to operate up to 100 kbps with maximum bus loading and timing. The device is
capable of operating at higher baud rates, up to a maximum of clock/20, with reduced bus loading. The
maximum communication length and the number of devices that can be connected are limited by a
maximum bus capacitance of 400 pF.
13.1.1
Features
The IIC module has the following key features:
• Compatible with I2C bus standard
• Multi-master operation
• Software programmable for one of 256 different serial clock frequencies
• Software selectable acknowledge bit
• Interrupt driven byte-by-byte data transfer
• Arbitration lost interrupt with automatic mode switching from master to slave
• Calling address identification interrupt
• Start and stop signal generation/detection
• Repeated start signal generation
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
479
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
•
•
•
•
Acknowledge bit generation/detection
Bus busy detection
General Call Address detection
Compliant to ten-bit address
MC9S12XHZ512 Data Sheet, Rev. 1.06
480
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.1.2
Modes of Operation
The IIC functions the same in normal, special, and emulation modes. It has two low power modes: wait
and stop modes.
13.1.3
Block Diagram
The block diagram of the IIC module is shown in Figure 13-1.
IIC
Registers
Start
Stop
Arbitration
Control
Clock
Control
In/Out
Data
Shift
Register
Interrupt
bus_clock
SCL
SDA
Address
Compare
Figure 13-1. IIC Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
481
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.2
External Signal Description
The IICV3 module has two external pins.
13.2.1
IIC_SCL — Serial Clock Line Pin
This is the bidirectional serial clock line (SCL) of the module, compatible to the IIC bus specification.
13.2.2
IIC_SDA — Serial Data Line Pin
This is the bidirectional serial data line (SDA) of the module, compatible to the IIC bus specification.
13.3
Memory Map and Register Definition
This section provides a detailed description of all memory and registers for the IIC module.
13.3.1
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Details of register bit and field function follow the register
diagrams, in bit order.
Register
Name
0x0000
IBAD
0x0001
IBFD
0x0002
IBCR
0x0003
IBSR
R
W
R
W
R
W
R
Bit 7
6
5
4
3
2
1
ADR7
ADR6
ADR5
ADR4
ADR3
ADR2
ADR1
IBC7
IBC6
IBC5
IBC4
IBC3
IBC2
IBC1
IBEN
IBIE
MS/SL
Tx/Rx
TXAK
0
0
TCF
IAAS
IBB
D7
D6
D5
GCEN
ADTYPE
0
W
0x0004
IBDR
R
W
0x0005
IBCR2
W
R
RSTA
Bit 0
0
IBC0
IBSWAI
0
SRW
D4
D3
D2
D1
D0
0
0
ADR10
ADR9
ADR8
IBAL
IBIF
RXAK
= Unimplemented or Reserved
Figure 13-2. IIC Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
482
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.3.1.1
IIC Address Register (IBAD)
Module Base +0x0000
7
6
5
4
3
2
1
ADR7
ADR6
ADR5
ADR4
ADR3
ADR2
ADR1
0
0
0
0
0
0
0
R
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 13-3. IIC Bus Address Register (IBAD)
Read and write anytime
This register contains the address the IIC bus will respond to when addressed as a slave; note that it is not
the address sent on the bus during the address transfer.
Table 13-2. IBAD Field Descriptions
Field
Description
7:1
ADR[7:1]
Slave Address — Bit 1 to bit 7 contain the specific slave address to be used by the IIC bus module.The default
mode of IIC bus is slave mode for an address match on the bus.
0
Reserved
Reserved — Bit 0 of the IBAD is reserved for future compatibility. This bit will always read 0.
13.3.1.2
IIC Frequency Divider Register (IBFD)
Module Base + 0x0001
7
6
5
4
3
2
1
0
IBC7
IBC6
IBC5
IBC4
IBC3
IBC2
IBC1
IBC0
0
0
0
0
0
0
0
0
R
W
Reset
= Unimplemented or Reserved
Figure 13-4. IIC Bus Frequency Divider Register (IBFD)
Read and write anytime
Table 13-3. IBFD Field Descriptions
Field
Description
7:0
IBC[7:0]
I Bus Clock Rate 7:0 — This field is used to prescale the clock for bit rate selection. The bit clock generator is
implemented as a prescale divider — IBC7:6, prescaled shift register — IBC5:3 select the prescaler divider and
IBC2-0 select the shift register tap point. The IBC bits are decoded to give the tap and prescale values as shown
in Table 13-4.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
483
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-4. I-Bus Tap and Prescale Values
IBC2-0
(bin)
SCL Tap
(clocks)
SDA Tap
(clocks)
000
5
1
001
6
1
010
7
2
011
8
2
100
9
3
101
10
3
110
12
4
111
15
4
Table 13-5. Prescale Divider Encoding
IBC5-3
(bin)
scl2start
(clocks)
scl2stop
(clocks)
scl2tap
(clocks)
tap2tap
(clocks)
000
2
7
4
1
001
2
7
4
2
010
2
9
6
4
011
6
9
6
8
100
14
17
14
16
101
30
33
30
32
110
62
65
62
64
111
126
129
126
128
Table 13-6. Multiplier Factor
IBC7-6
MUL
00
01
01
02
10
04
11
RESERVED
The number of clocks from the falling edge of SCL to the first tap (Tap[1]) is defined by the values shown
in the scl2tap column of Table 13-4, all subsequent tap points are separated by 2IBC5-3 as shown in the
tap2tap column in Table 13-5. The SCL Tap is used to generated the SCL period and the SDA Tap is used
to determine the delay from the falling edge of SCL to SDA changing, the SDA hold time.
IBC7–6 defines the multiplier factor MUL. The values of MUL are shown in the Table 13-6.
MC9S12XHZ512 Data Sheet, Rev. 1.06
484
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
SCL Divider
SCL
SDA Hold
SDA
SDA
SCL Hold(stop)
SCL Hold(start)
SCL
START condition
STOP condition
Figure 13-5. SCL Divider and SDA Hold
The equation used to generate the divider values from the IBFD bits is:
SCL Divider = MUL x {2 x (scl2tap + [(SCL_Tap -1) x tap2tap] + 2)}
The SDA hold delay is equal to the CPU clock period multiplied by the SDA Hold value shown in
Table 13-7. The equation used to generate the SDA Hold value from the IBFD bits is:
SDA Hold = MUL x {scl2tap + [(SDA_Tap - 1) x tap2tap] + 3}
The equation for SCL Hold values to generate the start and stop conditions from the IBFD bits is:
SCL Hold(start) = MUL x [scl2start + (SCL_Tap - 1) x tap2tap]
SCL Hold(stop) = MUL x [scl2stop + (SCL_Tap - 1) x tap2tap]
Table 13-7. IIC Divider and Hold Values (Sheet 1 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
MUL=1
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
485
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-7. IIC Divider and Hold Values (Sheet 2 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
20/22
22/24
24/26
26/28
28/30
30/32
34/36
40/42
28/32
32/36
36/40
40/44
44/48
48/52
56/60
68/72
48
56
64
72
80
88
104
128
80
96
112
128
144
160
192
240
160
192
224
256
288
320
384
480
320
384
448
512
576
7
7
8
8
9
9
10
10
7
7
9
9
11
11
13
13
9
9
13
13
17
17
21
21
9
9
17
17
25
25
33
33
17
17
33
33
49
49
65
65
33
33
65
65
97
6
7
8
9
10
11
13
16
10
12
14
16
18
20
24
30
18
22
26
30
34
38
46
58
38
46
54
62
70
78
94
118
78
94
110
126
142
158
190
238
158
190
222
254
286
11
12
13
14
15
16
18
21
15
17
19
21
23
25
29
35
25
29
33
37
41
45
53
65
41
49
57
65
73
81
97
121
81
97
113
129
145
161
193
241
161
193
225
257
289
MC9S12XHZ512 Data Sheet, Rev. 1.06
486
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-7. IIC Divider and Hold Values (Sheet 3 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
640
768
960
640
768
896
1024
1152
1280
1536
1920
1280
1536
1792
2048
2304
2560
3072
3840
97
129
129
65
65
129
129
193
193
257
257
129
129
257
257
385
385
513
513
318
382
478
318
382
446
510
574
638
766
958
638
766
894
1022
1150
1278
1534
1918
321
385
481
321
385
449
513
577
641
769
961
641
769
897
1025
1153
1281
1537
1921
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
40
44
48
52
56
60
68
80
56
64
72
80
88
96
112
136
96
112
128
144
160
176
208
256
160
14
14
16
16
18
18
20
20
14
14
18
18
22
22
26
26
18
18
26
26
34
34
42
42
18
12
14
16
18
20
22
26
32
20
24
28
32
36
40
48
60
36
44
52
60
68
76
92
116
76
22
24
26
28
30
32
36
42
30
34
38
42
46
50
58
70
50
58
66
74
82
90
106
130
82
MUL=2
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
487
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-7. IIC Divider and Hold Values (Sheet 4 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
59
5A
5B
5C
5D
5E
5F
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
192
224
256
288
320
384
480
320
384
448
512
576
640
768
960
640
768
896
1024
1152
1280
1536
1920
1280
1536
1792
2048
2304
2560
3072
3840
2560
3072
3584
4096
4608
5120
6144
7680
18
34
34
50
50
66
66
34
34
66
66
98
98
130
130
66
66
130
130
194
194
258
258
130
130
258
258
386
386
514
514
258
258
514
514
770
770
1026
1026
92
108
124
140
156
188
236
156
188
220
252
284
316
380
476
316
380
444
508
572
636
764
956
636
764
892
1020
1148
1276
1532
1916
1276
1532
1788
2044
2300
2556
3068
3836
98
114
130
146
162
194
242
162
194
226
258
290
322
386
482
322
386
450
514
578
642
770
962
642
770
898
1026
1154
1282
1538
1922
1282
1538
1794
2050
2306
2562
3074
3842
80
81
82
83
84
72
80
88
96
104
28
28
32
32
36
24
28
32
36
40
44
48
52
56
60
MUL=4
MC9S12XHZ512 Data Sheet, Rev. 1.06
488
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-7. IIC Divider and Hold Values (Sheet 5 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
85
86
87
88
89
8A
8B
8C
8D
8E
8F
90
91
92
93
94
95
96
97
98
99
9A
9B
9C
9D
9E
9F
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
AA
AB
AC
AD
AE
AF
B0
B1
112
128
152
112
128
144
160
176
192
224
272
192
224
256
288
320
352
416
512
320
384
448
512
576
640
768
960
640
768
896
1024
1152
1280
1536
1920
1280
1536
1792
2048
2304
2560
3072
3840
2560
3072
36
40
40
28
28
36
36
44
44
52
52
36
36
52
52
68
68
84
84
36
36
68
68
100
100
132
132
68
68
132
132
196
196
260
260
132
132
260
260
388
388
516
516
260
260
44
52
64
40
48
56
64
72
80
96
120
72
88
104
120
136
152
184
232
152
184
216
248
280
312
376
472
312
376
440
504
568
632
760
952
632
760
888
1016
1144
1272
1528
1912
1272
1528
64
72
84
60
68
76
84
92
100
116
140
100
116
132
148
164
180
212
260
164
196
228
260
292
324
388
484
324
388
452
516
580
644
772
964
644
772
900
1028
1156
1284
1540
1924
1284
1540
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
489
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-7. IIC Divider and Hold Values (Sheet 6 of 6)
IBC[7:0]
(hex)
SCL Divider
(clocks)
SDA Hold
(clocks)
SCL Hold
(start)
SCL Hold
(stop)
B2
B3
B4
B5
B6
B7
B8
B9
BA
BB
BC
BD
BE
BF
3584
4096
4608
5120
6144
7680
5120
6144
7168
8192
9216
10240
12288
15360
516
516
772
772
1028
1028
516
516
1028
1028
1540
1540
2052
2052
1784
2040
2296
2552
3064
3832
2552
3064
3576
4088
4600
5112
6136
7672
1796
2052
2308
2564
3076
3844
2564
3076
3588
4100
4612
5124
6148
7684
Note:Since the bus frequency is speeding up,the SCL Divider could be expanded by it.Therefore,in the
table,when IBC[7:0] is from $00 to $0F,the SCL Divider is revised by the format value1/value2.Value1 is
the divider under the low frequency.Value2 is the divider under the high frequency.How to select the
divider depends on the bus frequency.When IBC[7:0] is from $10 to $BF,the divider is not changed.
13.3.1.3
IIC Control Register (IBCR)
Module Base + 0x0002
7
6
5
4
3
IBEN
IBIE
MS/SL
Tx/Rx
TXAK
R
1
0
0
0
IBSWAI
RSTA
W
Reset
2
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-6. IIC Bus Control Register (IBCR)
Read and write anytime
MC9S12XHZ512 Data Sheet, Rev. 1.06
490
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-8. IBCR Field Descriptions
Field
Description
7
IBEN
I-Bus Enable — This bit controls the software reset of the entire IIC bus module.
0 The module is reset and disabled. This is the power-on reset situation. When low the interface is held in reset
but registers can be accessed
1 The IIC bus module is enabled.This bit must be set before any other IBCR bits have any effect
If the IIC bus module is enabled in the middle of a byte transfer the interface behaves as follows: slave mode
ignores the current transfer on the bus and starts operating whenever a subsequent start condition is detected.
Master mode will not be aware that the bus is busy, hence if a start cycle is initiated then the current bus cycle
may become corrupt. This would ultimately result in either the current bus master or the IIC bus module losing
arbitration, after which bus operation would return to normal.
6
IBIE
I-Bus Interrupt Enable
0 Interrupts from the IIC bus module are disabled. Note that this does not clear any currently pending interrupt
condition
1 Interrupts from the IIC bus module are enabled. An IIC bus interrupt occurs provided the IBIF bit in the status
register is also set.
5
MS/SL
Master/Slave Mode Select Bit — Upon reset, this bit is cleared. When this bit is changed from 0 to 1, a START
signal is generated on the bus, and the master mode is selected. When this bit is changed from 1 to 0, a STOP
signal is generated and the operation mode changes from master to slave.A STOP signal should only be
generated if the IBIF flag is set. MS/SL is cleared without generating a STOP signal when the master loses
arbitration.
0 Slave Mode
1 Master Mode
4
Tx/Rx
Transmit/Receive Mode Select Bit — This bit selects the direction of master and slave transfers. When
addressed as a slave this bit should be set by software according to the SRW bit in the status register. In master
mode this bit should be set according to the type of transfer required. Therefore, for address cycles, this bit will
always be high.
0 Receive
1 Transmit
3
TXAK
Transmit Acknowledge Enable — This bit specifies the value driven onto SDA during data acknowledge cycles
for both master and slave receivers. The IIC module will always acknowledge address matches, provided it is
enabled, regardless of the value of TXAK. Note that values written to this bit are only used when the IIC bus is a
receiver, not a transmitter.
0 An acknowledge signal will be sent out to the bus at the 9th clock bit after receiving one byte data
1 No acknowledge signal response is sent (i.e., acknowledge bit = 1)
2
RSTA
Repeat Start — Writing a 1 to this bit will generate a repeated START condition on the bus, provided it is the
current bus master. This bit will always be read as a low. Attempting a repeated start at the wrong time, if the bus
is owned by another master, will result in loss of arbitration.
1 Generate repeat start cycle
1
Reserved — Bit 1 of the IBCR is reserved for future compatibility. This bit will always read 0.
RESERVED
0
IBSWAI
I Bus Interface Stop in Wait Mode
0 IIC bus module clock operates normally
1 Halt IIC bus module clock generation in wait mode
Wait mode is entered via execution of a CPU WAI instruction. In the event that the IBSWAI bit is set, all
clocks internal to the IIC will be stopped and any transmission currently in progress will halt.If the CPU
were woken up by a source other than the IIC module, then clocks would restart and the IIC would resume
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
491
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
from where was during the previous transmission. It is not possible for the IIC to wake up the CPU when
its internal clocks are stopped.
If it were the case that the IBSWAI bit was cleared when the WAI instruction was executed, the IIC internal
clocks and interface would remain alive, continuing the operation which was currently underway. It is also
possible to configure the IIC such that it will wake up the CPU via an interrupt at the conclusion of the
current operation. See the discussion on the IBIF and IBIE bits in the IBSR and IBCR, respectively.
13.3.1.4
IIC Status Register (IBSR)
Module Base + 0x0003
R
7
6
5
TCF
IAAS
IBB
4
3
2
0
SRW
IBAL
1
0
RXAK
IBIF
W
Reset
1
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-7. IIC Bus Status Register (IBSR)
This status register is read-only with exception of bit 1 (IBIF) and bit 4 (IBAL), which are software
clearable.
Table 13-9. IBSR Field Descriptions
Field
Description
7
TCF
Data Transferring Bit — While one byte of data is being transferred, this bit is cleared. It is set by the falling
edge of the 9th clock of a byte transfer. Note that this bit is only valid during or immediately following a transfer
to the IIC module or from the IIC module.
0 Transfer in progress
1 Transfer complete
6
IAAS
Addressed as a Slave Bit — When its own specific address (I-bus address register) is matched with the calling
address or it receives the general call address with GCEN== 1,this bit is set.The CPU is interrupted provided the
IBIE is set.Then the CPU needs to check the SRW bit and set its Tx/Rx mode accordingly.Writing to the I-bus
control register clears this bit.
0 Not addressed
1 Addressed as a slave
5
IBB
Bus Busy Bit
0 This bit indicates the status of the bus. When a START signal is detected, the IBB is set. If a STOP signal is
detected, IBB is cleared and the bus enters idle state.
1 Bus is busy
4
IBAL
Arbitration Lost — The arbitration lost bit (IBAL) is set by hardware when the arbitration procedure is lost.
Arbitration is lost in the following circumstances:
1. SDA sampled low when the master drives a high during an address or data transmit cycle.
2. SDA sampled low when the master drives a high during the acknowledge bit of a data receive cycle.
3. A start cycle is attempted when the bus is busy.
4. A repeated start cycle is requested in slave mode.
5. A stop condition is detected when the master did not request it.
This bit must be cleared by software, by writing a one to it. A write of 0 has no effect on this bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
492
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Table 13-9. IBSR Field Descriptions (continued)
Field
Description
3
Reserved — Bit 3 of IBSR is reserved for future use. A read operation on this bit will return 0.
RESERVED
2
SRW
Slave Read/Write — When IAAS is set this bit indicates the value of the R/W command bit of the calling address
sent from the master
This bit is only valid when the I-bus is in slave mode, a complete address transfer has occurred with an address
match and no other transfers have been initiated.
Checking this bit, the CPU can select slave transmit/receive mode according to the command of the master.
0 Slave receive, master writing to slave
1 Slave transmit, master reading from slave
1
IBIF
I-Bus Interrupt — The IBIF bit is set when one of the following conditions occurs:
— Arbitration lost (IBAL bit set)
— Data transfer complete (TCF bit set)
— Addressed as slave (IAAS bit set)
It will cause a processor interrupt request if the IBIE bit is set. This bit must be cleared by software, writing a one
to it. A write of 0 has no effect on this bit.
0
RXAK
Received Acknowledge — The value of SDA during the acknowledge bit of a bus cycle. If the received
acknowledge bit (RXAK) is low, it indicates an acknowledge signal has been received after the completion of 8
bits data transmission on the bus. If RXAK is high, it means no acknowledge signal is detected at the 9th clock.
0 Acknowledge received
1 No acknowledge received
13.3.1.5
IIC Data I/O Register (IBDR)
Module Base + 0x0004
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 13-8. IIC Bus Data I/O Register (IBDR)
In master transmit mode, when data is written to the IBDR a data transfer is initiated. The most significant
bit is sent first. In master receive mode, reading this register initiates next byte data receiving. In slave
mode, the same functions are available after an address match has occurred.Note that the Tx/Rx bit in the
IBCR must correctly reflect the desired direction of transfer in master and slave modes for the transmission
to begin. For instance, if the IIC is configured for master transmit but a master receive is desired, then
reading the IBDR will not initiate the receive.
Reading the IBDR will return the last byte received while the IIC is configured in either master receive or
slave receive modes. The IBDR does not reflect every byte that is transmitted on the IIC bus, nor can
software verify that a byte has been written to the IBDR correctly by reading it back.
In master transmit mode, the first byte of data written to IBDR following assertion of MS/SL is used for
the address transfer and should com.prise of the calling address (in position D7:D1) concatenated with the
required R/W bit (in position D0).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
493
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.3.1.6
IIC Control Register 2(IBCR2)
Module Base + 0x0005
7
6
GCEN
ADTYPE
0
0
R
5
4
3
0
0
0
2
1
0
ADR10
ADR9
ADR8
0
0
0
W
Reset
0
0
0
Figure 13-9. IIC Bus Control Register 2(IBCR2)
This register contains the variables used in general call and in ten-bit address.
Read and write anytime
Table 13-10. IBCR2 Field Descriptions
Field
Description
General Call Enable.
0 General call is disabled. The module dont receive any general call data and address.
1 enable general call. It indicates that the module can receive address and any data.
7
GCEN
6
ADTYPE
Address Type— This bit selects the address length. The variable must be configured correctly before IIC enters
slave mode.
0 7-bit address
1 10-bit address
5,4,3
Reserved — Bit 5,4 and 3 of the IBCR2 are reserved for future compatibility. These bits will always read 0.
RESERVED
2:0
ADR[10:8]
13.4
Slave Address [10:8] —These 3 bits represent the MSB of the 10-bit address when address type is asserted
(ADTYPE = 1).
Functional Description
This section provides a complete functional description of the IICV3.
13.4.1
I-Bus Protocol
The IIC bus system uses a serial data line (SDA) and a serial clock line (SCL) for data transfer. All devices
connected to it must have open drain or open collector outputs. Logic AND function is exercised on both
lines with external pull-up resistors. The value of these resistors is system dependent.
Normally, a standard communication is composed of four parts: START signal, slave address transmission,
data transfer and STOP signal. They are described briefly in the following sections and illustrated in
Figure 13-10.
MC9S12XHZ512 Data Sheet, Rev. 1.06
494
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
MSB
CL
1
DA
LSB
2
3
4
5
6
7
8
MSB
9
ADR7 ADR6 ADR5 ADR4ADR3 ADR2 ADR1R/W
Calling Address
Start
Signal
Read/
Write
MSB
CL
1
DA
XXX
3
4
5
6
7
8
Calling Address
Read/
Write
3
4
5
6
7
8
D7
D6
D5
D4
D3
D2
D1
D0
Data Byte
1
XX
Ack
Bit
9
No
Ack
Bit
MSB
9
ADR7 ADR6 ADR5 ADR4 ADR3 ADR2 ADR1R/W
Start
Signal
2
Ack
Bit
LSB
2
LSB
1
LSB
2
3
4
5
6
7
8
9
ADR7 ADR6 ADR5 ADR4 ADR3 ADR2 ADR1R/W
Repeated
Start
Signal
New Calling Address
Read/
Write
No
Ack
Bit
Figure 13-10. IIC-Bus Transmission Signals
13.4.1.1
START Signal
When the bus is free, i.e. no master device is engaging the bus (both SCL and SDA lines are at logical
high), a master may initiate communication by sending a START signal.As shown in Figure 13-10, a
START signal is defined as a high-to-low transition of SDA while SCL is high. This signal denotes the
beginning of a new data transfer (each data transfer may contain several bytes of data) and brings all slaves
out of their idle states.
SDA
SCL
START Condition
STOP Condition
Figure 13-11. Start and Stop Conditions
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
495
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.4.1.2
Slave Address Transmission
The first byte of data transfer immediately after the START signal is the slave address transmitted by the
master. This is a seven-bit calling address followed by a R/W bit. The R/W bit tells the slave the desired
direction of data transfer.
1 = Read transfer, the slave transmits data to the master.
0 = Write transfer, the master transmits data to the slave.
If the calling address is 10-bit, another byte is followed by the first byte.Only the slave with a calling
address that matches the one transmitted by the master will respond by sending back an acknowledge bit.
This is done by pulling the SDA low at the 9th clock (see Figure 13-10).
No two slaves in the system may have the same address. If the IIC bus is master, it must not transmit an
address that is equal to its own slave address. The IIC bus cannot be master and slave at the same
time.However, if arbitration is lost during an address cycle the IIC bus will revert to slave mode and operate
correctly even if it is being addressed by another master.
13.4.1.3
Data Transfer
As soon as successful slave addressing is achieved, the data transfer can proceed byte-by-byte in a
direction specified by the R/W bit sent by the calling master
All transfers that come after an address cycle are referred to as data transfers, even if they carry sub-address
information for the slave device.
Each data byte is 8 bits long. Data may be changed only while SCL is low and must be held stable while
SCL is high as shown in Figure 13-10. There is one clock pulse on SCL for each data bit, the MSB being
transferred first. Each data byte has to be followed by an acknowledge bit, which is signalled from the
receiving device by pulling the SDA low at the ninth clock. So one complete data byte transfer needs nine
clock pulses.
If the slave receiver does not acknowledge the master, the SDA line must be left high by the slave. The
master can then generate a stop signal to abort the data transfer or a start signal (repeated start) to
commence a new calling.
If the master receiver does not acknowledge the slave transmitter after a byte transmission, it means 'end
of data' to the slave, so the slave releases the SDA line for the master to generate STOP or START
signal.Note in order to release the bus correctly,after no-acknowledge to the master,the slave must be
immediately switched to receiver and a following dummy reading of the IBDR is necessary.
13.4.1.4
STOP Signal
The master can terminate the communication by generating a STOP signal to free the bus. However, the
master may generate a START signal followed by a calling command without generating a STOP signal
first. This is called repeated START. A STOP signal is defined as a low-to-high transition of SDA while
SCL at logical 1 (see Figure 13-10).
The master can generate a STOP even if the slave has generated an acknowledge at which point the slave
must release the bus.
MC9S12XHZ512 Data Sheet, Rev. 1.06
496
Freescale Semiconductor
Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.4.1.5
Repeated START Signal
As shown in Figure 13-10, a repeated START signal is a START signal generated without first generating
a STOP signal to terminate the communication. This is used by the master to communicate with another
slave or with the same slave in different mode (transmit/receive mode) without releasing the bus.
13.4.1.6
Arbitration Procedure
The Inter-IC bus is a true multi-master bus that allows more than one master to be connected on it. If two
or more masters try to control the bus at the same time, a clock synchronization procedure determines the
bus clock, for which the low period is equal to the longest clock low period and the high is equal to the
shortest one among the masters. The relative priority of the contending masters is determined by a data
arbitration procedure, a bus master loses arbitration if it transmits logic 1 while another master transmits
logic 0. The losing masters immediately switch over to slave receive mode and stop driving SDA output.
In this case the transition from master to slave mode does not generate a STOP condition. Meanwhile, a
status bit is set by hardware to indicate loss of arbitration.
13.4.1.7
Clock Synchronization
Because wire-AND logic is performed on SCL line, a high-to-low transition on SCL line affects all the
devices connected on the bus. The devices start counting their low period and as soon as a device's clock
has gone low, it holds the SCL line low until the clock high state is reached.However, the change of low to
high in this device clock may not change the state of the SCL line if another device clock is within its low
period. Therefore, synchronized clock SCL is held low by the device with the longest low period. Devices
with shorter low periods enter a high wait state during this time (see Figure 13-11). When all devices
concerned have counted off their low period, the synchronized clock SCL line is released and pulled high.
There is then no difference between the device clocks and the state of the SCL line and all the devices start
counting their high periods.The first device to complete its high period pulls the SCL line low again.
WAIT
Start Counting High Period
SCL1
SCL2
SCL
Internal Counter Reset
Figure 13-12. IIC-Bus Clock Synchronization
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.4.1.8
Handshaking
The clock synchronization mechanism can be used as a handshake in data transfer. Slave devices may hold
the SCL low after completion of one byte transfer (9 bits). In such case, it halts the bus clock and forces
the master clock into wait states until the slave releases the SCL line.
13.4.1.9
Clock Stretching
The clock synchronization mechanism can be used by slaves to slow down the bit rate of a transfer. After
the master has driven SCL low the slave can drive SCL low for the required period and then release it.If
the slave SCL low period is greater than the master SCL low period then the resulting SCL bus signal low
period is stretched.
13.4.1.10 Ten-bit Address
A ten-bit address is indicated if the first 5 bits of the first address byte are 0x11110. The following rules
apply to the first address byte.
SLAVE
ADDRESS
0000000
R/W BIT
DESCRIPTION
0
0000010
x
0000011
11111XX
11110XX
x
x
x
General call address
Reserved for different bus
format
Reserved for future purposes
Reserved for future purposes
10-bit slave addressing
Figure 13-13. Definition
of bits in the first byte.
The address type is identified by ADTYPE. When ADTYPE is 0, 7-bit address is applied. Reversely, the
address is 10-bit address.Generally, there are two cases of 10-bit address.See the Figure 13-14 and
Figure 13-15.
S
Slave Add1st 7bits
11110+ADR10+ADR9
R/W
0
A1
Slave Add 2nd byte
ADR[8:1]
A2
Data
A3
Figure 13-14. A master-transmitter addresses a slave-receiver with a 10-bit address
S
Slave Add1st 7bits
11110+ADR10+ADR9
R/W
0
A1
Slave Add 2nd byte
ADR[8:1]
A2
Sr
Slave Add 1st 7bits
R/W
11110+ADR10+ADR9
1
A3
Data
Figure 13-15. A master-receiver addresses a slave-transmitter with a 10-bit address.
In the Figure 13-15, the first two bytes are the similar to Figure 13-14. After the repeated START(Sr),the
first slave address is transmitted again, but the R/W is 1, meaning that the slave is acted as a transmitter.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.4.1.11 General Call Address
To broadcast using a general call, a device must first generate the general call address($00), then after
receiving acknowledge, it must transmit data.
In communication, as a slave device, provided the GCEN is asserted, a device acknowledges the broadcast
and receives data until the GCEN is disabled or the master device releases the bus or generates a new
transfer. In the broadcast, slaves always act as receivers. In general call, IAAS is also used to indicate the
address match.
In order to distinguish whether the address match is the normal address match or the general call address
match, IBDR should be read after the address byte has been received. If the data is $00, the match is
general call address match. The meaning of the general call address is always specified in the first data byte
and must be dealt with by S/W, the IIC hardware does not decode and process the first data byte.
When one byte transfer is done, the received data can be read from IBDR. The user can control the
procedure by enabling or disabling GCEN.
13.4.2
Operation in Run Mode
This is the basic mode of operation.
13.4.3
Operation in Wait Mode
IIC operation in wait mode can be configured. Depending on the state of internal bits, the IIC can operate
normally when the CPU is in wait mode or the IIC clock generation can be turned off and the IIC module
enters a power conservation state during wait mode. In the later case, any transmission or reception in
progress stops at wait mode entry.
13.4.4
Operation in Stop Mode
The IIC is inactive in stop mode for reduced power consumption. The STOP instruction does not affect IIC
register states.
13.5
Resets
The reset state of each individual bit is listed in Section 13.3, “Memory Map and Register Definition,”
which details the registers and their bit-fields.
13.6
Interrupts
IICV3 uses only one interrupt vector.
Table 13-11. Interrupt Summary
Interrupt
Offset
Vector
Priority
Source
Description
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
IIC
Interrupt
—
—
—
IBAL, TCF, IAAS When either of IBAL, TCF or IAAS bits is set
may cause an interrupt based on arbitration
bits in IBSR
lost, transfer complete or address detect
register
conditions
Internally there are three types of interrupts in IIC. The interrupt service routine can determine the interrupt
type by reading the status register.
IIC Interrupt can be generated on
1. Arbitration lost condition (IBAL bit set)
2. Byte transfer condition (TCF bit set)
3. Address detect condition (IAAS bit set)
The IIC interrupt is enabled by the IBIE bit in the IIC control register. It must be cleared by writing 0 to
the IBF bit in the interrupt service routine.
13.7
Application Information
13.7.1
13.7.1.1
IIC Programming Examples
Initialization Sequence
Reset will put the IIC bus control register to its default status. Before the interface can be used to transfer
serial data, an initialization procedure must be carried out, as follows:
1. Update the frequency divider register (IBFD) and select the required division ratio to obtain SCL
frequency from system clock.
2. Update the ADTYPE of IBCR2 to define the address length, 7 bits or 10 bits.
3. Update the IIC bus address register (IBAD) to define its slave address. If 10-bit address is applied
IBCR2 should be updated to define the rest bits of address.
4. Set the IBEN bit of the IIC bus control register (IBCR) to enable the IIC interface system.
5. Modify the bits of the IIC bus control register (IBCR) to select master/slave mode, transmit/receive
mode and interrupt enable or not.
6. If supported general call, the GCEN in IBCR2 should be asserted.
13.7.1.2
Generation of START
After completion of the initialization procedure, serial data can be transmitted by selecting the 'master
transmitter' mode. If the device is connected to a multi-master bus system, the state of the IIC bus busy bit
(IBB) must be tested to check whether the serial bus is free.
If the bus is free (IBB=0), the start condition and the first byte (the slave address) can be sent. The data
written to the data register comprises the slave calling address and the LSB set to indicate the direction of
transfer required from the slave.
The bus free time (i.e., the time between a STOP condition and the following START condition) is built
into the hardware that generates the START cycle. Depending on the relative frequencies of the system
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
clock and the SCL period it may be necessary to wait until the IIC is busy after writing the calling address
to the IBDR before proceeding with the following instructions. This is illustrated in the following example.
An example of a program which generates the START signal and transmits the first byte of data (slave
address) is shown below:
CHFLAG
BRSET
IBSR,#$20,*
;WAIT FOR IBB FLAG TO CLEAR
TXSTART
BSET
IBCR,#$30
;SET TRANSMIT AND MASTER MODE;i.e. GENERATE START CONDITION
MOVB
CALLING,IBDR
;TRANSMIT THE CALLING ADDRESS, D0=R/W
BRCLR
IBSR,#$20,*
;WAIT FOR IBB FLAG TO SET
IBFREE
13.7.1.3
Post-Transfer Software Response
Transmission or reception of a byte will set the data transferring bit (TCF) to 1, which indicates one byte
communication is finished. The IIC bus interrupt bit (IBIF) is set also; an interrupt will be generated if the
interrupt function is enabled during initialization by setting the IBIE bit. Software must clear the IBIF bit
in the interrupt routine first. The TCF bit will be cleared by reading from the IIC bus data I/O register
(IBDR) in receive mode or writing to IBDR in transmit mode.
Software may service the IIC I/O in the main program by monitoring the IBIF bit if the interrupt function
is disabled. Note that polling should monitor the IBIF bit rather than the TCF bit because their operation
is different when arbitration is lost.
Note that when an interrupt occurs at the end of the address cycle the master will always be in transmit
mode, i.e. the address is transmitted. If master receive mode is required, indicated by R/W bit in IBDR,
then the Tx/Rx bit should be toggled at this stage.
During slave mode address cycles (IAAS=1), the SRW bit in the status register is read to determine the
direction of the subsequent transfer and the Tx/Rx bit is programmed accordingly.For slave mode data
cycles (IAAS=0) the SRW bit is not valid, the Tx/Rx bit in the control register should be read to determine
the direction of the current transfer.
The following is an example of a software response by a 'master transmitter' in the interrupt routine.
ISR
TRANSMIT
BCLR
BRCLR
BRCLR
BRSET
MOVB
IBSR,#$02
IBCR,#$20,SLAVE
IBCR,#$10,RECEIVE
IBSR,#$01,END
DATABUF,IBDR
13.7.1.4
Generation of STOP
;CLEAR THE IBIF FLAG
;BRANCH IF IN SLAVE MODE
;BRANCH IF IN RECEIVE MODE
;IF NO ACK, END OF TRANSMISSION
;TRANSMIT NEXT BYTE OF DATA
A data transfer ends with a STOP signal generated by the 'master' device. A master transmitter can simply
generate a STOP signal after all the data has been transmitted. The following is an example showing how
a stop condition is generated by a master transmitter.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
MASTX
END
EMASTX
TST
BEQ
BRSET
MOVB
DEC
BRA
BCLR
RTI
TXCNT
END
IBSR,#$01,END
DATABUF,IBDR
TXCNT
EMASTX
IBCR,#$20
;GET VALUE FROM THE TRANSMITING COUNTER
;END IF NO MORE DATA
;END IF NO ACK
;TRANSMIT NEXT BYTE OF DATA
;DECREASE THE TXCNT
;EXIT
;GENERATE A STOP CONDITION
;RETURN FROM INTERRUPT
If a master receiver wants to terminate a data transfer, it must inform the slave transmitter by not
acknowledging the last byte of data which can be done by setting the transmit acknowledge bit (TXAK)
before reading the 2nd last byte of data. Before reading the last byte of data, a STOP signal must be
generated first. The following is an example showing how a STOP signal is generated by a master receiver.
MASR
DEC
BEQ
MOVB
DEC
BNE
BSET
RXCNT
ENMASR
RXCNT,D1
D1
NXMAR
IBCR,#$08
ENMASR
NXMAR
BRA
BCLR
MOVB
RTI
NXMAR
IBCR,#$20
IBDR,RXBUF
13.7.1.5
Generation of Repeated START
LAMAR
;DECREASE THE RXCNT
;LAST BYTE TO BE READ
;CHECK SECOND LAST BYTE
;TO BE READ
;NOT LAST OR SECOND LAST
;SECOND LAST, DISABLE ACK
;TRANSMITTING
;LAST ONE, GENERATE ‘STOP’ SIGNAL
;READ DATA AND STORE
At the end of data transfer, if the master continues to want to communicate on the bus, it can generate
another START signal followed by another slave address without first generating a STOP signal. A
program example is as shown.
RESTART
BSET
MOVB
IBCR,#$04
CALLING,IBDR
13.7.1.6
Slave Mode
;ANOTHER START (RESTART)
;TRANSMIT THE CALLING ADDRESS;D0=R/W
In the slave interrupt service routine, the module addressed as slave bit (IAAS) should be tested to check
if a calling of its own address has just been received. If IAAS is set, software should set the transmit/receive
mode select bit (Tx/Rx bit of IBCR) according to the R/W command bit (SRW). Writing to the IBCR
clears the IAAS automatically. Note that the only time IAAS is read as set is from the interrupt at the end
of the address cycle where an address match occurred, interrupts resulting from subsequent data transfers
will have IAAS cleared. A data transfer may now be initiated by writing information to IBDR, for slave
transmits, or dummy reading from IBDR, in slave receive mode. The slave will drive SCL low in-between
byte transfers, SCL is released when the IBDR is accessed in the required mode.
In slave transmitter routine, the received acknowledge bit (RXAK) must be tested before transmitting the
next byte of data. Setting RXAK means an 'end of data' signal from the master receiver, after which it must
be switched from transmitter mode to receiver mode by software. A dummy read then releases the SCL
line so that the master can generate a STOP signal.
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
13.7.1.7
Arbitration Lost
If several masters try to engage the bus simultaneously, only one master wins and the others lose
arbitration. The devices which lost arbitration are immediately switched to slave receive mode by the
hardware. Their data output to the SDA line is stopped, but SCL continues to be generated until the end of
the byte during which arbitration was lost. An interrupt occurs at the falling edge of the ninth clock of this
transfer with IBAL=1 and MS/SL=0. If one master attempts to start transmission while the bus is being
engaged by another master, the hardware will inhibit the transmission; switch the MS/SL bit from 1 to 0
without generating STOP condition; generate an interrupt to CPU and set the IBAL to indicate that the
attempt to engage the bus is failed. When considering these cases, the slave service routine should test the
IBAL first and the software should clear the IBAL bit if it is set.
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Clear
IBIF
Master
Mode
?
Y
TX
N
RX
Tx/Rx
?
Y
Arbitration
Lost
?
N
Last Byte
Transmitted
?
N
Clear IBAL
Y
RXAK=0
?
Last
Byte To Be Read
?
N
End Of
Addr Cycle
(Master Rx)
?
N
Y
2nd Last
Byte To Be Read
?
Y
(Read)
Set TXAK =1
Y
Y
10-bit
address?
7-bit address transfer
Data Transfer
TX/RX
?
TX
SRW=1
?
N (Write) Y
Generate
Stop Signal
IAAS=1
?
N
N
N
Write Next
Byte To IBDR
Y
IAAS=1
?
N
Y
Y
N
Y
Set TX
Mode
ACK From
Receiver
?
N
10-bit address transfer
N
IBDR==
11110xx1?
Y
set RX
Mode
Read Data
From IBDR
And Store
Tx Next
Byte
Write Data
To IBDR
Switch To
Rx Mode
RX
set TX
Mode
Dummy Read
From IBDR
Set RX
Mode
Switch To
Rx Mode
Write Data
To IBDR
Dummy Read
From IBDR
Generate
Stop Signal
Read Data
From IBDR
And Store
Dummy Read
From IBDR
Dummy Read
From IBDR
RTI
Figure 13-16. Flow-Chart of Typical IIC Interrupt Routine
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
Caution:When IIC is configured as 10-bit address,the point of the data array in interrupt routine must be
reset after it’s addressed.
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Chapter 13 Inter-Integrated Circuit (IICV3) Block Description
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 14
Freescale’s Scalable Controller Area Network
(S12MSCANV3)
Table 14-1. Revision History
Revision
Number
Revision Date
V03.10
19 Aug 2008
V03.11
31 Mar 2009
V03.12
09 Aug 2010
14.1
Sections
Affected
Description of Changes
14.4.7.4/14-559 - Corrected wake-up description
14.4.4.5/14-553 - Relocated initialization section
14.2/14-510
- Added note to external pin descriptions for use with integrated physical layer
- Minor corrections
- Orthographic corrections
Table 14-37
- Added ‘Bosch CAN 2.0A/B’ to bit time settings table
Introduction
Freescale’s scalable controller area network (S12MSCANV3) definition is based on the MSCAN12
definition, which is the specific implementation of the MSCAN concept targeted for the M68HC12
microcontroller family.
The module is a communication controller implementing the CAN 2.0A/B protocol as defined in the
Bosch specification dated September 1991. For users to fully understand the MSCAN specification, it is
recommended that the Bosch specification be read first to familiarize the reader with the terms and
concepts contained within this document.
Though not exclusively intended for automotive applications, CAN protocol is designed to meet the
specific requirements of a vehicle serial data bus: real-time processing, reliable operation in the EMI
environment of a vehicle, cost-effectiveness, and required bandwidth.
MSCAN uses an advanced buffer arrangement resulting in predictable real-time behavior and simplified
application software.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.1.1
Glossary
Table 14-2. Terminology
ACK
Acknowledge of CAN message
CAN
Controller Area Network
CRC
Cyclic Redundancy Code
EOF
End of Frame
FIFO
First-In-First-Out Memory
IFS
Inter-Frame Sequence
SOF
Start of Frame
CPU bus
CPU related read/write data bus
CAN bus
CAN protocol related serial bus
oscillator clock
14.1.2
Direct clock from external oscillator
bus clock
CPU bus related clock
CAN clock
CAN protocol related clock
Block Diagram
MSCAN
Oscillator Clock
Bus Clock
CANCLK
MUX
Presc.
Tq Clk
Receive/
Transmit
Engine
RXCAN
TXCAN
Transmit Interrupt Req.
Receive Interrupt Req.
Errors Interrupt Req.
Message
Filtering
and
Buffering
Control
and
Status
Wake-Up Interrupt Req.
Configuration
Registers
Wake-Up
Low Pass Filter
Figure 14-1. MSCAN Block Diagram
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.1.3
Features
The basic features of the MSCAN are as follows:
• Implementation of the CAN protocol — Version 2.0A/B
— Standard and extended data frames
— Zero to eight bytes data length
— Programmable bit rate up to 1 Mbps1
— Support for remote frames
• Five receive buffers with FIFO storage scheme
• Three transmit buffers with internal prioritization using a “local priority” concept
• Flexible maskable identifier filter supports two full-size (32-bit) extended identifier filters, or four
16-bit filters, or eight 8-bit filters
• Programmable wake-up functionality with integrated low-pass filter
• Programmable loopback mode supports self-test operation
• Programmable listen-only mode for monitoring of CAN bus
• Programmable bus-off recovery functionality
• Separate signalling and interrupt capabilities for all CAN receiver and transmitter error states
(warning, error passive, bus-off)
• Programmable MSCAN clock source either bus clock or oscillator clock
• Internal timer for time-stamping of received and transmitted messages
• Three low-power modes: sleep, power down, and MSCAN enable
• Global initialization of configuration registers
14.1.4
Modes of Operation
For a description of the specific MSCAN modes and the module operation related to the system operating
modes refer to Section 14.4.4, “Modes of Operation”.
1. Depending on the actual bit timing and the clock jitter of the PLL.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.2
External Signal Description
The MSCAN uses two external pins.
NOTE
On MCUs with an integrated CAN physical interface (transceiver) the
MSCAN interface is connected internally to the transceiver interface. In
these cases the external availability of signals TXCAN and RXCAN is
optional.
14.2.1
RXCAN — CAN Receiver Input Pin
RXCAN is the MSCAN receiver input pin.
14.2.2
TXCAN — CAN Transmitter Output Pin
TXCAN is the MSCAN transmitter output pin. The TXCAN output pin represents the logic level on the
CAN bus:
0 = Dominant state
1 = Recessive state
14.2.3
CAN System
A typical CAN system with MSCAN is shown in Figure 14-2. Each CAN station is connected physically
to the CAN bus lines through a transceiver device. The transceiver is capable of driving the large current
needed for the CAN bus and has current protection against defective CAN or defective stations.
CAN node 2
CAN node 1
CAN node n
MCU
CAN Controller
(MSCAN)
TXCAN
RXCAN
Transceiver
CANH
CANL
CAN Bus
Figure 14-2. CAN System
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the MSCAN.
14.3.1
Module Memory Map
Figure 14-3 gives an overview on all registers and their individual bits in the MSCAN memory map. The
register address results from the addition of base address and address offset. The base address is
determined at the MCU level and can be found in the MCU memory map description. The address offset
is defined at the module level.
The MSCAN occupies 64 bytes in the memory space. The base address of the MSCAN module is
determined at the MCU level when the MCU is defined. The register decode map is fixed and begins at the
first address of the module address offset.
The detailed register descriptions follow in the order they appear in the register map.
MC9S12XHZ512 Data Sheet Rev. 1.06
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Register
Name
Bit 7
0x0000
CANCTL0
R
0x0001
CANCTL1
R
W
W
0x0002
CANBTR0
R
0x0003
CANBTR1
R
0x0004
CANRFLG
R
0x0005
CANRIER
R
0x0006
CANTFLG
R
0x0007
CANTIER
0x0008
CANTARQ
W
W
W
W
R
R
W
0x000E
CANRXERR
SYNCH
3
2
1
Bit 0
TIME
WUPE
SLPRQ
INITRQ
SLPAK
INITAK
CANE
CLKSRC
LOOPB
LISTEN
BORM
WUPM
SJW1
SJW0
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
SAMP
TSEG22
TSEG21
TSEG20
TSEG13
TSEG12
TSEG11
TSEG10
WUPIF
CSCIF
RSTAT1
RSTAT0
TSTAT1
TSTAT0
OVRIF
RXF
WUPIE
CSCIE
RSTATE1
RSTATE0
TSTATE1
TSTATE0
OVRIE
RXFIE
0
0
0
0
0
TXE2
TXE1
TXE0
0
0
0
0
0
TXEIE2
TXEIE1
TXEIE0
0
0
0
0
0
ABTRQ2
ABTRQ1
ABTRQ0
0
0
0
0
0
ABTAK2
ABTAK1
ABTAK0
0
0
0
0
0
TX2
TX1
TX0
0
0
IDAM1
IDAM0
0
IDHIT2
IDHIT1
IDHIT0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RXERR7
RXERR6
RXERR5
RXERR4
RXERR3
RXERR2
RXERR1
W
0x000A
CANTBSEL
0x000D
CANMISC
CSWAI
4
W
W
0x000C
Reserved
RXACT
5
W
0x0009
CANTAAK
0x000B
CANIDAC
RXFRM
6
R
R
R
W
R
W
R
W
R
BOHOLD
RXERR0
W
= Unimplemented or Reserved
Figure 14-3. MSCAN Register Summary
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Register
Name
0x000F
CANTXERR
R
0x0010–0x0013
CANIDAR0–3
R
0x0014–0x0017
CANIDMRx
R
0x0018–0x001B
CANIDAR4–7
R
0x001C–0x001F
CANIDMR4–7
R
0x0020–0x002F
CANRXFG
R
0x0030–0x003F
CANTXFG
R
Bit 7
6
5
4
3
2
1
Bit 0
TXERR7
TXERR6
TXERR5
TXERR4
TXERR3
TXERR2
TXERR1
TXERR0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
W
W
W
W
W
See Section 14.3.3, “Programmer’s Model of Message Storage”
W
See Section 14.3.3, “Programmer’s Model of Message Storage”
W
= Unimplemented or Reserved
Figure 14-3. MSCAN Register Summary (continued)
14.3.2
Register Descriptions
This section describes in detail all the registers and register bits in the MSCAN module. Each description
includes a standard register diagram with an associated figure number. Details of register bit and field
function follow the register diagrams, in bit order. All bits of all registers in this module are completely
synchronous to internal clocks during a register read.
14.3.2.1
MSCAN Control Register 0 (CANCTL0)
The CANCTL0 register provides various control bits of the MSCAN module as described below.
Access: User read/write(1)
Module Base + 0x0000
7
R
6
5
RXACT
RXFRM
4
3
2
1
0
TIME
WUPE
SLPRQ
INITRQ
0
0
0
1
SYNCH
CSWAI
W
Reset:
0
0
0
0
= Unimplemented
Figure 14-4. MSCAN Control Register 0 (CANCTL0)
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
1. Read: Anytime
Write: Anytime when out of initialization mode; exceptions are read-only RXACT and SYNCH, RXFRM (which is set by the
module only), and INITRQ (which is also writable in initialization mode)
NOTE
The CANCTL0 register, except WUPE, INITRQ, and SLPRQ, is held in the
reset state when the initialization mode is active (INITRQ = 1 and
INITAK = 1). This register is writable again as soon as the initialization
mode is exited (INITRQ = 0 and INITAK = 0).
Table 14-3. CANCTL0 Register Field Descriptions
Field
Description
7
RXFRM(1)
Received Frame Flag — This bit is read and clear only. It is set when a receiver has received a valid message
correctly, independently of the filter configuration. After it is set, it remains set until cleared by software or reset.
Clearing is done by writing a 1. Writing a 0 is ignored. This bit is not valid in loopback mode.
0 No valid message was received since last clearing this flag
1 A valid message was received since last clearing of this flag
6
RXACT
Receiver Active Status — This read-only flag indicates the MSCAN is receiving a message. The flag is
controlled by the receiver front end. This bit is not valid in loopback mode.
0 MSCAN is transmitting or idle2
1 MSCAN is receiving a message (including when arbitration is lost)(2)
5
CSWAI(3)
CAN Stops in Wait Mode — Enabling this bit allows for lower power consumption in wait mode by disabling all
the clocks at the CPU bus interface to the MSCAN module.
0 The module is not affected during wait mode
1 The module ceases to be clocked during wait mode
4
SYNCH
Synchronized Status — This read-only flag indicates whether the MSCAN is synchronized to the CAN bus and
able to participate in the communication process. It is set and cleared by the MSCAN.
0 MSCAN is not synchronized to the CAN bus
1 MSCAN is synchronized to the CAN bus
3
TIME
Timer Enable — This bit activates an internal 16-bit wide free running timer which is clocked by the bit clock rate.
If the timer is enabled, a 16-bit time stamp will be assigned to each transmitted/received message within the
active TX/RX buffer. Right after the EOF of a valid message on the CAN bus, the time stamp is written to the
highest bytes (0x000E, 0x000F) in the appropriate buffer (see Section 14.3.3, “Programmer’s Model of Message
Storage”). The internal timer is reset (all bits set to 0) when disabled. This bit is held low in initialization mode.
0 Disable internal MSCAN timer
1 Enable internal MSCAN timer
2
WUPE(4)
Wake-Up Enable — This configuration bit allows the MSCAN to restart from sleep mode or from power down
mode (entered from sleep) when traffic on CAN is detected (see Section 14.4.5.5, “MSCAN Sleep Mode”). This
bit must be configured before sleep mode entry for the selected function to take effect.
0 Wake-up disabled — The MSCAN ignores traffic on CAN
1 Wake-up enabled — The MSCAN is able to restart
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Table 14-3. CANCTL0 Register Field Descriptions (continued)
Field
Description
1
SLPRQ(5)
Sleep Mode Request — This bit requests the MSCAN to enter sleep mode, which is an internal power saving
mode (see Section 14.4.5.5, “MSCAN Sleep Mode”). The sleep mode request is serviced when the CAN bus is
idle, i.e., the module is not receiving a message and all transmit buffers are empty. The module indicates entry
to sleep mode by setting SLPAK = 1 (see Section 14.3.2.2, “MSCAN Control Register 1 (CANCTL1)”). SLPRQ
cannot be set while the WUPIF flag is set (see Section 14.3.2.5, “MSCAN Receiver Flag Register (CANRFLG)”).
Sleep mode will be active until SLPRQ is cleared by the CPU or, depending on the setting of WUPE, the MSCAN
detects activity on the CAN bus and clears SLPRQ itself.
0 Running — The MSCAN functions normally
1 Sleep mode request — The MSCAN enters sleep mode when CAN bus idle
0
Initialization Mode Request — When this bit is set by the CPU, the MSCAN skips to initialization mode (see
INITRQ(6),(7) Section 14.4.4.5, “MSCAN Initialization Mode”). Any ongoing transmission or reception is aborted and
synchronization to the CAN bus is lost. The module indicates entry to initialization mode by setting INITAK = 1
(Section 14.3.2.2, “MSCAN Control Register 1 (CANCTL1)”).
The following registers enter their hard reset state and restore their default values: CANCTL0(8), CANRFLG(9),
CANRIER(10), CANTFLG, CANTIER, CANTARQ, CANTAAK, and CANTBSEL.
The registers CANCTL1, CANBTR0, CANBTR1, CANIDAC, CANIDAR0-7, and CANIDMR0-7 can only be
written by the CPU when the MSCAN is in initialization mode (INITRQ = 1 and INITAK = 1). The values of the
error counters are not affected by initialization mode.
When this bit is cleared by the CPU, the MSCAN restarts and then tries to synchronize to the CAN bus. If the
MSCAN is not in bus-off state, it synchronizes after 11 consecutive recessive bits on the CAN bus; if the MSCAN
is in bus-off state, it continues to wait for 128 occurrences of 11 consecutive recessive bits.
Writing to other bits in CANCTL0, CANRFLG, CANRIER, CANTFLG, or CANTIER must be done only after
initialization mode is exited, which is INITRQ = 0 and INITAK = 0.
0 Normal operation
1 MSCAN in initialization mode
1. The MSCAN must be in normal mode for this bit to become set.
2. See the Bosch CAN 2.0A/B specification for a detailed definition of transmitter and receiver states.
3. In order to protect from accidentally violating the CAN protocol, TXCAN is immediately forced to a recessive state when the
CPU enters wait (CSWAI = 1) or stop mode (see Section 14.4.5.2, “Operation in Wait Mode” and Section 14.4.5.3, “Operation
in Stop Mode”).
4. The CPU has to make sure that the WUPE register and the WUPIE wake-up interrupt enable register (see Section 14.3.2.6,
“MSCAN Receiver Interrupt Enable Register (CANRIER)) is enabled, if the recovery mechanism from stop or wait is required.
5. The CPU cannot clear SLPRQ before the MSCAN has entered sleep mode (SLPRQ = 1 and SLPAK = 1).
6. The CPU cannot clear INITRQ before the MSCAN has entered initialization mode (INITRQ = 1 and INITAK = 1).
7. In order to protect from accidentally violating the CAN protocol, TXCAN is immediately forced to a recessive state when the
initialization mode is requested by the CPU. Thus, the recommended procedure is to bring the MSCAN into sleep mode
(SLPRQ = 1 and SLPAK = 1) before requesting initialization mode.
8. Not including WUPE, INITRQ, and SLPRQ.
9. TSTAT1 and TSTAT0 are not affected by initialization mode.
10. RSTAT1 and RSTAT0 are not affected by initialization mode.
14.3.2.2
MSCAN Control Register 1 (CANCTL1)
The CANCTL1 register provides various control bits and handshake status information of the MSCAN
module as described below.
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Access: User read/write(1)
Module Base + 0x0001
7
6
5
4
3
2
CANE
CLKSRC
LOOPB
LISTEN
BORM
WUPM
0
0
0
1
0
0
R
1
0
SLPAK
INITAK
0
1
W
Reset:
= Unimplemented
Figure 14-5. MSCAN Control Register 1 (CANCTL1)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1); CANE is write once
Table 14-4. CANCTL1 Register Field Descriptions
Field
7
CANE
Description
MSCAN Enable
0 MSCAN module is disabled
1 MSCAN module is enabled
6
CLKSRC
MSCAN Clock Source — This bit defines the clock source for the MSCAN module (only for systems with a clock
generation module; Section 14.4.3.2, “Clock System,” and Section Figure 14-43., “MSCAN Clocking Scheme,”).
0 MSCAN clock source is the oscillator clock
1 MSCAN clock source is the bus clock
5
LOOPB
Loopback Self Test Mode — When this bit is set, the MSCAN performs an internal loopback which can be used
for self test operation. The bit stream output of the transmitter is fed back to the receiver internally. The RXCAN
input is ignored and the TXCAN output goes to the recessive state (logic 1). The MSCAN behaves as it does
normally when transmitting and treats its own transmitted message as a message received from a remote node.
In this state, the MSCAN ignores the bit sent during the ACK slot in the CAN frame acknowledge field to ensure
proper reception of its own message. Both transmit and receive interrupts are generated.
0 Loopback self test disabled
1 Loopback self test enabled
4
LISTEN
Listen Only Mode — This bit configures the MSCAN as a CAN bus monitor. When LISTEN is set, all valid CAN
messages with matching ID are received, but no acknowledgement or error frames are sent out (see
Section 14.4.4.4, “Listen-Only Mode”). In addition, the error counters are frozen. Listen only mode supports
applications which require “hot plugging” or throughput analysis. The MSCAN is unable to transmit any
messages when listen only mode is active.
0 Normal operation
1 Listen only mode activated
3
BORM
Bus-Off Recovery Mode — This bit configures the bus-off state recovery mode of the MSCAN. Refer to
Section 14.5.2, “Bus-Off Recovery,” for details.
0 Automatic bus-off recovery (see Bosch CAN 2.0A/B protocol specification)
1 Bus-off recovery upon user request
2
WUPM
Wake-Up Mode — If WUPE in CANCTL0 is enabled, this bit defines whether the integrated low-pass filter is
applied to protect the MSCAN from spurious wake-up (see Section 14.4.5.5, “MSCAN Sleep Mode”).
0 MSCAN wakes up on any dominant level on the CAN bus
1 MSCAN wakes up only in case of a dominant pulse on the CAN bus that has a length of Twup
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Table 14-4. CANCTL1 Register Field Descriptions (continued)
Field
Description
1
SLPAK
Sleep Mode Acknowledge — This flag indicates whether the MSCAN module has entered sleep mode (see
Section 14.4.5.5, “MSCAN Sleep Mode”). It is used as a handshake flag for the SLPRQ sleep mode request.
Sleep mode is active when SLPRQ = 1 and SLPAK = 1. Depending on the setting of WUPE, the MSCAN will
clear the flag if it detects activity on the CAN bus while in sleep mode.
0 Running — The MSCAN operates normally
1 Sleep mode active — The MSCAN has entered sleep mode
0
INITAK
Initialization Mode Acknowledge — This flag indicates whether the MSCAN module is in initialization mode
(see Section 14.4.4.5, “MSCAN Initialization Mode”). It is used as a handshake flag for the INITRQ initialization
mode request. Initialization mode is active when INITRQ = 1 and INITAK = 1. The registers CANCTL1,
CANBTR0, CANBTR1, CANIDAC, CANIDAR0–CANIDAR7, and CANIDMR0–CANIDMR7 can be written only by
the CPU when the MSCAN is in initialization mode.
0 Running — The MSCAN operates normally
1 Initialization mode active — The MSCAN has entered initialization mode
14.3.2.3
MSCAN Bus Timing Register 0 (CANBTR0)
The CANBTR0 register configures various CAN bus timing parameters of the MSCAN module.
Access: User read/write(1)
Module Base + 0x0002
7
6
5
4
3
2
1
0
SJW1
SJW0
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 14-6. MSCAN Bus Timing Register 0 (CANBTR0)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 14-5. CANBTR0 Register Field Descriptions
Field
Description
7-6
SJW[1:0]
Synchronization Jump Width — The synchronization jump width defines the maximum number of time quanta
(Tq) clock cycles a bit can be shortened or lengthened to achieve resynchronization to data transitions on the
CAN bus (see Table 14-6).
5-0
BRP[5:0]
Baud Rate Prescaler — These bits determine the time quanta (Tq) clock which is used to build up the bit timing
(see Table 14-7).
Table 14-6. Synchronization Jump Width
SJW1
SJW0
Synchronization Jump Width
0
0
1 Tq clock cycle
0
1
2 Tq clock cycles
1
0
3 Tq clock cycles
1
1
4 Tq clock cycles
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Table 14-7. Baud Rate Prescaler
14.3.2.4
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
Prescaler value (P)
0
0
0
0
0
0
1
0
0
0
0
0
1
2
0
0
0
0
1
0
3
0
0
0
0
1
1
4
:
:
:
:
:
:
:
1
1
1
1
1
1
64
MSCAN Bus Timing Register 1 (CANBTR1)
The CANBTR1 register configures various CAN bus timing parameters of the MSCAN module.
Access: User read/write(1)
Module Base + 0x0003
7
6
5
4
3
2
1
0
SAMP
TSEG22
TSEG21
TSEG20
TSEG13
TSEG12
TSEG11
TSEG10
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 14-7. MSCAN Bus Timing Register 1 (CANBTR1)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 14-8. CANBTR1 Register Field Descriptions
Field
Description
7
SAMP
Sampling — This bit determines the number of CAN bus samples taken per bit time.
0 One sample per bit.
1 Three samples per bit(1).
If SAMP = 0, the resulting bit value is equal to the value of the single bit positioned at the sample point. If
SAMP = 1, the resulting bit value is determined by using majority rule on the three total samples. For higher bit
rates, it is recommended that only one sample is taken per bit time (SAMP = 0).
6-4
Time Segment 2 — Time segments within the bit time fix the number of clock cycles per bit time and the location
TSEG2[2:0] of the sample point (see Figure 14-44). Time segment 2 (TSEG2) values are programmable as shown in
Table 14-9.
3-0
Time Segment 1 — Time segments within the bit time fix the number of clock cycles per bit time and the location
TSEG1[3:0] of the sample point (see Figure 14-44). Time segment 1 (TSEG1) values are programmable as shown in
Table 14-10.
1. In this case, PHASE_SEG1 must be at least 2 time quanta (Tq).
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Table 14-9. Time Segment 2 Values
TSEG22
TSEG21
TSEG20
Time Segment 2
0
0
0
1 Tq clock cycle(1)
0
0
1
2 Tq clock cycles
:
:
:
:
1
1
0
7 Tq clock cycles
1
1
1
8 Tq clock cycles
1. This setting is not valid. Please refer to Table 14-37 for valid settings.
Table 14-10. Time Segment 1 Values
TSEG13
TSEG12
TSEG11
TSEG10
Time segment 1
0
0
0
0
1 Tq clock cycle(1)
0
0
0
1
2 Tq clock cycles1
0
0
1
0
3 Tq clock cycles1
0
0
1
1
4 Tq clock cycles
:
:
:
:
:
1
1
1
0
15 Tq clock cycles
1
1
1
1
16 Tq clock cycles
1. This setting is not valid. Please refer to Table 14-37 for valid settings.
The bit time is determined by the oscillator frequency, the baud rate prescaler, and the number of time
quanta (Tq) clock cycles per bit (as shown in Table 14-9 and Table 14-10).
Eqn. 14-1
( Prescaler value )
Bit Time = ------------------------------------------------------ • ( 1 + TimeSegment1 + TimeSegment2 )
f CANCLK
14.3.2.5
MSCAN Receiver Flag Register (CANRFLG)
A flag can be cleared only by software (writing a 1 to the corresponding bit position) when the condition
which caused the setting is no longer valid. Every flag has an associated interrupt enable bit in the
CANRIER register.
Access: User read/write(1)
Module Base + 0x0004
7
6
WUPIF
CSCIF
0
0
R
5
4
3
2
RSTAT1
RSTAT0
TSTAT1
TSTAT0
1
0
OVRIF
RXF
0
0
W
Reset:
0
0
0
0
= Unimplemented
Figure 14-8. MSCAN Receiver Flag Register (CANRFLG)
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1. Read: Anytime
Write: Anytime when not in initialization mode, except RSTAT[1:0] and TSTAT[1:0] flags which are read-only; write of 1 clears
flag; write of 0 is ignored
NOTE
The CANRFLG register is held in the reset state1 when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable again
as soon as the initialization mode is exited (INITRQ = 0 and INITAK = 0).
Table 14-11. CANRFLG Register Field Descriptions
Field
Description
7
WUPIF
Wake-Up Interrupt Flag — If the MSCAN detects CAN bus activity while in sleep mode (see Section 14.4.5.5,
“MSCAN Sleep Mode,”) and WUPE = 1 in CANTCTL0 (see Section 14.3.2.1, “MSCAN Control Register 0
(CANCTL0)”), the module will set WUPIF. If not masked, a wake-up interrupt is pending while this flag is set.
0
No wake-up activity observed while in sleep mode
1
MSCAN detected activity on the CAN bus and requested wake-up
6
CSCIF
CAN Status Change Interrupt Flag — This flag is set when the MSCAN changes its current CAN bus status
due to the actual value of the transmit error counter (TEC) and the receive error counter (REC). An additional 4bit (RSTAT[1:0], TSTAT[1:0]) status register, which is split into separate sections for TEC/REC, informs the
system on the actual CAN bus status (see Section 14.3.2.6, “MSCAN Receiver Interrupt Enable Register
(CANRIER)”). If not masked, an error interrupt is pending while this flag is set. CSCIF provides a blocking
interrupt. That guarantees that the receiver/transmitter status bits (RSTAT/TSTAT) are only updated when no
CAN status change interrupt is pending. If the TECs/RECs change their current value after the CSCIF is
asserted, which would cause an additional state change in the RSTAT/TSTAT bits, these bits keep their status
until the current CSCIF interrupt is cleared again.
0
No change in CAN bus status occurred since last interrupt
1
MSCAN changed current CAN bus status
5-4
RSTAT[1:0]
Receiver Status Bits — The values of the error counters control the actual CAN bus status of the MSCAN. As
soon as the status change interrupt flag (CSCIF) is set, these bits indicate the appropriate receiver related CAN
bus status of the MSCAN. The coding for the bits RSTAT1, RSTAT0 is:
00
RxOK: 0 ≤ receive error counter ≤ 96
01
RxWRN: 96 < receive error counter ≤ 127
10
RxERR: 127 < receive error counter
11
Bus-off(1): transmit error counter > 255
3-2
TSTAT[1:0]
Transmitter Status Bits — The values of the error counters control the actual CAN bus status of the MSCAN.
As soon as the status change interrupt flag (CSCIF) is set, these bits indicate the appropriate transmitter related
CAN bus status of the MSCAN. The coding for the bits TSTAT1, TSTAT0 is:
00
TxOK: 0 ≤ transmit error counter ≤ 96
01
TxWRN: 96 < transmit error counter ≤ 127
10
TxERR: 127 < transmit error counter ≤ 255
11
Bus-Off: transmit error counter > 255
1. The RSTAT[1:0], TSTAT[1:0] bits are not affected by initialization mode.
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Table 14-11. CANRFLG Register Field Descriptions (continued)
Field
Description
1
OVRIF
Overrun Interrupt Flag — This flag is set when a data overrun condition occurs. If not masked, an error interrupt
is pending while this flag is set.
0
No data overrun condition
1
A data overrun detected
0
RXF(2)
Receive Buffer Full Flag — RXF is set by the MSCAN when a new message is shifted in the receiver FIFO.
This flag indicates whether the shifted buffer is loaded with a correctly received message (matching identifier,
matching cyclic redundancy code (CRC) and no other errors detected). After the CPU has read that message
from the RxFG buffer in the receiver FIFO, the RXF flag must be cleared to release the buffer. A set RXF flag
prohibits the shifting of the next FIFO entry into the foreground buffer (RxFG). If not masked, a receive interrupt
is pending while this flag is set.
0
No new message available within the RxFG
1
The receiver FIFO is not empty. A new message is available in the RxFG
1. Redundant Information for the most critical CAN bus status which is “bus-off”. This only occurs if the Tx error counter exceeds
a number of 255 errors. Bus-off affects the receiver state. As soon as the transmitter leaves its bus-off state the receiver state
skips to RxOK too. Refer also to TSTAT[1:0] coding in this register.
2. To ensure data integrity, do not read the receive buffer registers while the RXF flag is cleared. For MCUs with dual CPUs,
reading the receive buffer registers while the RXF flag is cleared may result in a CPU fault condition.
14.3.2.6
MSCAN Receiver Interrupt Enable Register (CANRIER)
This register contains the interrupt enable bits for the interrupt flags described in the CANRFLG register.
Access: User read/write(1)
Module Base + 0x0005
7
6
5
4
3
2
1
0
WUPIE
CSCIE
RSTATE1
RSTATE0
TSTATE1
TSTATE0
OVRIE
RXFIE
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 14-9. MSCAN Receiver Interrupt Enable Register (CANRIER)
1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANRIER register is held in the reset state when the initialization mode
is active (INITRQ=1 and INITAK=1). This register is writable when not in
initialization mode (INITRQ=0 and INITAK=0).
The RSTATE[1:0], TSTATE[1:0] bits are not affected by initialization
mode.
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Table 14-12. CANRIER Register Field Descriptions
Field
7
WUPIE(1)
6
CSCIE
Description
Wake-Up Interrupt Enable
0 No interrupt request is generated from this event.
1 A wake-up event causes a Wake-Up interrupt request.
CAN Status Change Interrupt Enable
0 No interrupt request is generated from this event.
1 A CAN Status Change event causes an error interrupt request.
5-4
Receiver Status Change Enable — These RSTAT enable bits control the sensitivity level in which receiver state
RSTATE[1:0] changes are causing CSCIF interrupts. Independent of the chosen sensitivity level the RSTAT flags continue to
indicate the actual receiver state and are only updated if no CSCIF interrupt is pending.
00 Do not generate any CSCIF interrupt caused by receiver state changes.
01 Generate CSCIF interrupt only if the receiver enters or leaves “bus-off” state. Discard other receiver state
changes for generating CSCIF interrupt.
10 Generate CSCIF interrupt only if the receiver enters or leaves “RxErr” or “bus-off”(2) state. Discard other
receiver state changes for generating CSCIF interrupt.
11 Generate CSCIF interrupt on all state changes.
3-2
Transmitter Status Change Enable — These TSTAT enable bits control the sensitivity level in which transmitter
TSTATE[1:0] state changes are causing CSCIF interrupts. Independent of the chosen sensitivity level, the TSTAT flags
continue to indicate the actual transmitter state and are only updated if no CSCIF interrupt is pending.
00 Do not generate any CSCIF interrupt caused by transmitter state changes.
01 Generate CSCIF interrupt only if the transmitter enters or leaves “bus-off” state. Discard other transmitter
state changes for generating CSCIF interrupt.
10 Generate CSCIF interrupt only if the transmitter enters or leaves “TxErr” or “bus-off” state. Discard other
transmitter state changes for generating CSCIF interrupt.
11 Generate CSCIF interrupt on all state changes.
1
OVRIE
Overrun Interrupt Enable
0 No interrupt request is generated from this event.
1 An overrun event causes an error interrupt request.
0
RXFIE
Receiver Full Interrupt Enable
0 No interrupt request is generated from this event.
1 A receive buffer full (successful message reception) event causes a receiver interrupt request.
1. WUPIE and WUPE (see Section 14.3.2.1, “MSCAN Control Register 0 (CANCTL0)”) must both be enabled if the recovery
mechanism from stop or wait is required.
2. Bus-off state is only defined for transmitters by the CAN standard (see Bosch CAN 2.0A/B protocol specification). Because
the only possible state change for the transmitter from bus-off to TxOK also forces the receiver to skip its current state to RxOK,
the coding of the RXSTAT[1:0] flags define an additional bus-off state for the receiver (see Section 14.3.2.5, “MSCAN Receiver
Flag Register (CANRFLG)”).
14.3.2.7
MSCAN Transmitter Flag Register (CANTFLG)
The transmit buffer empty flags each have an associated interrupt enable bit in the CANTIER register.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Access: User read/write(1)
Module Base + 0x0006
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TXE2
TXE1
TXE0
1
1
1
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 14-10. MSCAN Transmitter Flag Register (CANTFLG)
1. Read: Anytime
Write: Anytime when not in initialization mode; write of 1 clears flag, write of 0 is ignored
NOTE
The CANTFLG register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 14-13. CANTFLG Register Field Descriptions
Field
Description
2-0
TXE[2:0]
Transmitter Buffer Empty — This flag indicates that the associated transmit message buffer is empty, and thus
not scheduled for transmission. The CPU must clear the flag after a message is set up in the transmit buffer and
is due for transmission. The MSCAN sets the flag after the message is sent successfully. The flag is also set by
the MSCAN when the transmission request is successfully aborted due to a pending abort request (see
Section 14.3.2.9, “MSCAN Transmitter Message Abort Request Register (CANTARQ)”). If not masked, a
transmit interrupt is pending while this flag is set.
Clearing a TXEx flag also clears the corresponding ABTAKx (see Section 14.3.2.10, “MSCAN Transmitter
Message Abort Acknowledge Register (CANTAAK)”). When a TXEx flag is set, the corresponding ABTRQx bit
is cleared (see Section 14.3.2.9, “MSCAN Transmitter Message Abort Request Register (CANTARQ)”).
When listen-mode is active (see Section 14.3.2.2, “MSCAN Control Register 1 (CANCTL1)”) the TXEx flags
cannot be cleared and no transmission is started.
Read and write accesses to the transmit buffer will be blocked, if the corresponding TXEx bit is cleared
(TXEx = 0) and the buffer is scheduled for transmission.
0 The associated message buffer is full (loaded with a message due for transmission)
1 The associated message buffer is empty (not scheduled)
14.3.2.8
MSCAN Transmitter Interrupt Enable Register (CANTIER)
This register contains the interrupt enable bits for the transmit buffer empty interrupt flags.
Access: User read/write(1)
Module Base + 0x0007
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TXEIE2
TXEIE1
TXEIE0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 14-11. MSCAN Transmitter Interrupt Enable Register (CANTIER)
MC9S12XHZ512 Data Sheet Rev. 1.06
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANTIER register is held in the reset state when the initialization mode
is active (INITRQ = 1 and INITAK = 1). This register is writable when not
in initialization mode (INITRQ = 0 and INITAK = 0).
Table 14-14. CANTIER Register Field Descriptions
Field
Description
2-0
TXEIE[2:0]
14.3.2.9
Transmitter Empty Interrupt Enable
0 No interrupt request is generated from this event.
1 A transmitter empty (transmit buffer available for transmission) event causes a transmitter empty interrupt
request.
MSCAN Transmitter Message Abort Request Register (CANTARQ)
The CANTARQ register allows abort request of queued messages as described below.
Access: User read/write(1)
Module Base + 0x0008
R
7
6
5
4
3
0
0
0
0
0
2
1
0
ABTRQ2
ABTRQ1
ABTRQ0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 14-12. MSCAN Transmitter Message Abort Request Register (CANTARQ)
1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANTARQ register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 14-15. CANTARQ Register Field Descriptions
Field
Description
2-0
Abort Request — The CPU sets the ABTRQx bit to request that a scheduled message buffer (TXEx = 0) be
ABTRQ[2:0] aborted. The MSCAN grants the request if the message has not already started transmission, or if the
transmission is not successful (lost arbitration or error). When a message is aborted, the associated TXE (see
Section 14.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and abort acknowledge flags (ABTAK, see
Section 14.3.2.10, “MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)”) are set and a
transmit interrupt occurs if enabled. The CPU cannot reset ABTRQx. ABTRQx is reset whenever the associated
TXE flag is set.
0 No abort request
1 Abort request pending
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3.2.10 MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)
The CANTAAK register indicates the successful abort of a queued message, if requested by the
appropriate bits in the CANTARQ register.
Access: User read/write(1)
Module Base + 0x0009
R
7
6
5
4
3
2
1
0
0
0
0
0
0
ABTAK2
ABTAK1
ABTAK0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 14-13. MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)
1. Read: Anytime
Write: Unimplemented
NOTE
The CANTAAK register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1).
Table 14-16. CANTAAK Register Field Descriptions
Field
Description
2-0
Abort Acknowledge — This flag acknowledges that a message was aborted due to a pending abort request
ABTAK[2:0] from the CPU. After a particular message buffer is flagged empty, this flag can be used by the application
software to identify whether the message was aborted successfully or was sent anyway. The ABTAKx flag is
cleared whenever the corresponding TXE flag is cleared.
0 The message was not aborted.
1 The message was aborted.
14.3.2.11 MSCAN Transmit Buffer Selection Register (CANTBSEL)
The CANTBSEL register allows the selection of the actual transmit message buffer, which then will be
accessible in the CANTXFG register space.
Access: User read/write(1)
Module Base + 0x000A
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TX2
TX1
TX0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 14-14. MSCAN Transmit Buffer Selection Register (CANTBSEL)
1. Read: Find the lowest ordered bit set to 1, all other bits will be read as 0
Write: Anytime when not in initialization mode
MC9S12XHZ512 Data Sheet Rev. 1.06
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
NOTE
The CANTBSEL register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK=1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 14-17. CANTBSEL Register Field Descriptions
Field
Description
2-0
TX[2:0]
Transmit Buffer Select — The lowest numbered bit places the respective transmit buffer in the CANTXFG
register space (e.g., TX1 = 1 and TX0 = 1 selects transmit buffer TX0; TX1 = 1 and TX0 = 0 selects transmit
buffer TX1). Read and write accesses to the selected transmit buffer will be blocked, if the corresponding TXEx
bit is cleared and the buffer is scheduled for transmission (see Section 14.3.2.7, “MSCAN Transmitter Flag
Register (CANTFLG)”).
0 The associated message buffer is deselected
1 The associated message buffer is selected, if lowest numbered bit
The following gives a short programming example of the usage of the CANTBSEL register:
To get the next available transmit buffer, application software must read the CANTFLG register and write
this value back into the CANTBSEL register. In this example Tx buffers TX1 and TX2 are available. The
value read from CANTFLG is therefore 0b0000_0110. When writing this value back to CANTBSEL, the
Tx buffer TX1 is selected in the CANTXFG because the lowest numbered bit set to 1 is at bit position 1.
Reading back this value out of CANTBSEL results in 0b0000_0010, because only the lowest numbered
bit position set to 1 is presented. This mechanism eases the application software’s selection of the next
available Tx buffer.
• LDAA CANTFLG; value read is 0b0000_0110
• STAA CANTBSEL; value written is 0b0000_0110
• LDAA CANTBSEL; value read is 0b0000_0010
If all transmit message buffers are deselected, no accesses are allowed to the CANTXFG registers.
14.3.2.12 MSCAN Identifier Acceptance Control Register (CANIDAC)
The CANIDAC register is used for identifier acceptance control as described below.
Access: User read/write(1)
Module Base + 0x000B
R
7
6
0
0
5
4
IDAM1
IDAM0
0
0
3
2
1
0
0
IDHIT2
IDHIT1
IDHIT0
0
0
0
0
W
Reset:
0
0
= Unimplemented
Figure 14-15. MSCAN Identifier Acceptance Control Register (CANIDAC)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1), except bits IDHITx, which are read-only
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Table 14-18. CANIDAC Register Field Descriptions
Field
Description
5-4
IDAM[1:0]
Identifier Acceptance Mode — The CPU sets these flags to define the identifier acceptance filter organization
(see Section 14.4.3, “Identifier Acceptance Filter”). Table 14-19 summarizes the different settings. In filter closed
mode, no message is accepted such that the foreground buffer is never reloaded.
2-0
IDHIT[2:0]
Identifier Acceptance Hit Indicator — The MSCAN sets these flags to indicate an identifier acceptance hit (see
Section 14.4.3, “Identifier Acceptance Filter”). Table 14-20 summarizes the different settings.
Table 14-19. Identifier Acceptance Mode Settings
IDAM1
IDAM0
Identifier Acceptance Mode
0
0
Two 32-bit acceptance filters
0
1
Four 16-bit acceptance filters
1
0
Eight 8-bit acceptance filters
1
1
Filter closed
Table 14-20. Identifier Acceptance Hit Indication
IDHIT2
IDHIT1
IDHIT0
Identifier Acceptance Hit
0
0
0
Filter 0 hit
0
0
1
Filter 1 hit
0
1
0
Filter 2 hit
0
1
1
Filter 3 hit
1
0
0
Filter 4 hit
1
0
1
Filter 5 hit
1
1
0
Filter 6 hit
1
1
1
Filter 7 hit
The IDHITx indicators are always related to the message in the foreground buffer (RxFG). When a
message gets shifted into the foreground buffer of the receiver FIFO the indicators are updated as well.
14.3.2.13 MSCAN Reserved Register
This register is reserved for factory testing of the MSCAN module and is not available in normal system
operating modes.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Access: User read/write(1)
Module Base + 0x000C to Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 14-16. MSCAN Reserved Register
1. Read: Always reads zero in normal system operation modes
Write: Unimplemented in normal system operation modes
NOTE
Writing to this register when in special system operating modes can alter the
MSCAN functionality.
14.3.2.14 MSCAN Miscellaneous Register (CANMISC)
This register provides additional features.
Access: User read/write(1)
Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
BOHOLD
W
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 14-17. MSCAN Miscellaneous Register (CANMISC)
1. Read: Anytime
Write: Anytime; write of ‘1’ clears flag; write of ‘0’ ignored
Table 14-21. CANMISC Register Field Descriptions
Field
Description
0
BOHOLD
Bus-off State Hold Until User Request — If BORM is set in MSCAN Control Register 1 (CANCTL1), this bit
indicates whether the module has entered the bus-off state. Clearing this bit requests the recovery from bus-off.
Refer to Section 14.5.2, “Bus-Off Recovery,” for details.
0 Module is not bus-off or recovery has been requested by user in bus-off state
1 Module is bus-off and holds this state until user request
14.3.2.15 MSCAN Receive Error Counter (CANRXERR)
This register reflects the status of the MSCAN receive error counter.
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Access: User read/write(1)
Module Base + 0x000E
R
7
6
5
4
3
2
1
0
RXERR7
RXERR6
RXERR5
RXERR4
RXERR3
RXERR2
RXERR1
RXERR0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 14-18. MSCAN Receive Error Counter (CANRXERR)
1. Read: Only when in sleep mode (SLPRQ = 1 and SLPAK = 1) or initialization mode (INITRQ = 1 and INITAK = 1)
Write: Unimplemented
NOTE
Reading this register when in any other mode other than sleep or
initialization mode may return an incorrect value. For MCUs with dual
CPUs, this may result in a CPU fault condition.
Writing to this register when in special modes can alter the MSCAN
functionality.
14.3.2.16 MSCAN Transmit Error Counter (CANTXERR)
This register reflects the status of the MSCAN transmit error counter.
Access: User read/write(1)
Module Base + 0x000F
R
7
6
5
4
3
2
1
0
TXERR7
TXERR6
TXERR5
TXERR4
TXERR3
TXERR2
TXERR1
TXERR0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 14-19. MSCAN Transmit Error Counter (CANTXERR)
1. Read: Only when in sleep mode (SLPRQ = 1 and SLPAK = 1) or initialization mode (INITRQ = 1 and INITAK = 1)
Write: Unimplemented
NOTE
Reading this register when in any other mode other than sleep or
initialization mode, may return an incorrect value. For MCUs with dual
CPUs, this may result in a CPU fault condition.
Writing to this register when in special modes can alter the MSCAN
functionality.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3.2.17 MSCAN Identifier Acceptance Registers (CANIDAR0-7)
On reception, each message is written into the background receive buffer. The CPU is only signalled to
read the message if it passes the criteria in the identifier acceptance and identifier mask registers
(accepted); otherwise, the message is overwritten by the next message (dropped).
The acceptance registers of the MSCAN are applied on the IDR0–IDR3 registers (see Section 14.3.3.1,
“Identifier Registers (IDR0–IDR3)”) of incoming messages in a bit by bit manner (see Section 14.4.3,
“Identifier Acceptance Filter”).
For extended identifiers, all four acceptance and mask registers are applied. For standard identifiers, only
the first two (CANIDAR0/1, CANIDMR0/1) are applied.
Access: User read/write(1)
Module Base + 0x0010 to Module Base + 0x0013
7
6
5
4
3
2
1
0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-20. MSCAN Identifier Acceptance Registers (First Bank) — CANIDAR0–CANIDAR3
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 14-22. CANIDAR0–CANIDAR3 Register Field Descriptions
Field
Description
7-0
AC[7:0]
Acceptance Code Bits — AC[7:0] comprise a user-defined sequence of bits with which the corresponding bits
of the related identifier register (IDRn) of the receive message buffer are compared. The result of this comparison
is then masked with the corresponding identifier mask register.
Access: User read/write(1)
Module Base + 0x0018 to Module Base + 0x001B
7
6
5
4
3
2
1
0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-21. MSCAN Identifier Acceptance Registers (Second Bank) — CANIDAR4–CANIDAR7
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Table 14-23. CANIDAR4–CANIDAR7 Register Field Descriptions
Field
Description
7-0
AC[7:0]
Acceptance Code Bits — AC[7:0] comprise a user-defined sequence of bits with which the corresponding bits
of the related identifier register (IDRn) of the receive message buffer are compared. The result of this comparison
is then masked with the corresponding identifier mask register.
14.3.2.18 MSCAN Identifier Mask Registers (CANIDMR0–CANIDMR7)
The identifier mask register specifies which of the corresponding bits in the identifier acceptance register
are relevant for acceptance filtering. To receive standard identifiers in 32 bit filter mode, it is required to
program the last three bits (AM[2:0]) in the mask registers CANIDMR1 and CANIDMR5 to “don’t care.”
To receive standard identifiers in 16 bit filter mode, it is required to program the last three bits (AM[2:0])
in the mask registers CANIDMR1, CANIDMR3, CANIDMR5, and CANIDMR7 to “don’t care.”
Access: User read/write(1)
Module Base + 0x0014 to Module Base + 0x0017
7
6
5
4
3
2
1
0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-22. MSCAN Identifier Mask Registers (First Bank) — CANIDMR0–CANIDMR3
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 14-24. CANIDMR0–CANIDMR3 Register Field Descriptions
Field
Description
7-0
AM[7:0]
Acceptance Mask Bits — If a particular bit in this register is cleared, this indicates that the corresponding bit in
the identifier acceptance register must be the same as its identifier bit before a match is detected. The message
is accepted if all such bits match. If a bit is set, it indicates that the state of the corresponding bit in the identifier
acceptance register does not affect whether or not the message is accepted.
0 Match corresponding acceptance code register and identifier bits
1 Ignore corresponding acceptance code register bit
Access: User read/write(1)
Module Base + 0x001C to Module Base + 0x001F
7
6
5
4
3
2
1
0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-23. MSCAN Identifier Mask Registers (Second Bank) — CANIDMR4–CANIDMR7
MC9S12XHZ512 Data Sheet Rev. 1.06
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531
Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 14-25. CANIDMR4–CANIDMR7 Register Field Descriptions
Field
Description
7-0
AM[7:0]
Acceptance Mask Bits — If a particular bit in this register is cleared, this indicates that the corresponding bit in
the identifier acceptance register must be the same as its identifier bit before a match is detected. The message
is accepted if all such bits match. If a bit is set, it indicates that the state of the corresponding bit in the identifier
acceptance register does not affect whether or not the message is accepted.
0 Match corresponding acceptance code register and identifier bits
1 Ignore corresponding acceptance code register bit
14.3.3
Programmer’s Model of Message Storage
The following section details the organization of the receive and transmit message buffers and the
associated control registers.
To simplify the programmer interface, the receive and transmit message buffers have the same outline.
Each message buffer allocates 16 bytes in the memory map containing a 13 byte data structure.
An additional transmit buffer priority register (TBPR) is defined for the transmit buffers. Within the last
two bytes of this memory map, the MSCAN stores a special 16-bit time stamp, which is sampled from an
internal timer after successful transmission or reception of a message. This feature is only available for
transmit and receiver buffers, if the TIME bit is set (see Section 14.3.2.1, “MSCAN Control Register 0
(CANCTL0)”).
The time stamp register is written by the MSCAN. The CPU can only read these registers.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Table 14-26. Message Buffer Organization
Offset
Address
Register
Access
0x00X0
Identifier Register 0
R/W
0x00X1
Identifier Register 1
R/W
0x00X2
Identifier Register 2
R/W
0x00X3
Identifier Register 3
R/W
0x00X4
Data Segment Register 0
R/W
0x00X5
Data Segment Register 1
R/W
0x00X6
Data Segment Register 2
R/W
0x00X7
Data Segment Register 3
R/W
0x00X8
Data Segment Register 4
R/W
0x00X9
Data Segment Register 5
R/W
0x00XA
Data Segment Register 6
R/W
0x00XB
Data Segment Register 7
R/W
0x00XC
Data Length Register
R/W
(1)
0x00XD
Transmit Buffer Priority Register
R/W
0x00XE
Time Stamp Register (High Byte)
R
0x00XF
Time Stamp Register (Low Byte)
1. Not applicable for receive buffers
R
Figure 14-24 shows the common 13-byte data structure of receive and transmit buffers for extended
identifiers. The mapping of standard identifiers into the IDR registers is shown in Figure 14-25.
All bits of the receive and transmit buffers are ‘x’ out of reset because of RAM-based implementation1.
All reserved or unused bits of the receive and transmit buffers always read ‘x’.
1. Exception: The transmit buffer priority registers are 0 out of reset.
MC9S12XHZ512 Data Sheet Rev. 1.06
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Figure 14-24. Receive/Transmit Message Buffer — Extended Identifier Mapping
Register
Name
0x00X0
IDR0
0x00X1
IDR1
0x00X2
IDR2
0x00X3
IDR3
0x00X4
DSR0
0x00X5
DSR1
0x00X6
DSR2
0x00X7
DSR3
0x00X8
DSR4
0x00X9
DSR5
0x00XA
DSR6
0x00XB
DSR7
0x00XC
DLR
Bit 7
6
5
4
3
2
1
Bit0
ID28
ID27
ID26
ID25
ID24
ID23
ID22
ID21
ID20
ID19
ID18
SRR (=1)
IDE (=1)
ID17
ID16
ID15
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DLC3
DLC2
DLC1
DLC0
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Figure 14-24. Receive/Transmit Message Buffer — Extended Identifier Mapping (continued)
Register
Name
Bit 7
6
5
4
3
2
1
Bit0
= Unused, always read ‘x’
Read:
• For transmit buffers, anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter
Flag Register (CANTFLG)”) and the corresponding transmit buffer is selected in CANTBSEL (see
Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register (CANTBSEL)”).
• For receive buffers, only when RXF flag is set (see Section 14.3.2.5, “MSCAN Receiver Flag
Register (CANRFLG)”).
Write:
•
•
For transmit buffers, anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter
Flag Register (CANTFLG)”) and the corresponding transmit buffer is selected in CANTBSEL (see
Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register (CANTBSEL)”).
Unimplemented for receive buffers.
Reset: Undefined because of RAM-based implementation
Figure 14-25. Receive/Transmit Message Buffer — Standard Identifier Mapping
Register
Name
IDR0
0x00X0
IDR1
0x00X1
IDR2
0x00X2
IDR3
0x00X3
Bit 7
6
5
4
3
2
1
Bit 0
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
IDE (=0)
R
W
R
W
R
W
R
W
= Unused, always read ‘x’
14.3.3.1
Identifier Registers (IDR0–IDR3)
The identifier registers for an extended format identifier consist of a total of 32 bits: ID[28:0], SRR, IDE,
and RTR. The identifier registers for a standard format identifier consist of a total of 13 bits: ID[10:0],
RTR, and IDE.
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3.3.1.1
IDR0–IDR3 for Extended Identifier Mapping
Module Base + 0x00X0
7
6
5
4
3
2
1
0
ID28
ID27
ID26
ID25
ID24
ID23
ID22
ID21
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-26. Identifier Register 0 (IDR0) — Extended Identifier Mapping
Table 14-27. IDR0 Register Field Descriptions — Extended
Field
Description
7-0
ID[28:21]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
Module Base + 0x00X1
7
6
5
4
3
2
1
0
ID20
ID19
ID18
SRR (=1)
IDE (=1)
ID17
ID16
ID15
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-27. Identifier Register 1 (IDR1) — Extended Identifier Mapping
Table 14-28. IDR1 Register Field Descriptions — Extended
Field
Description
7-5
ID[20:18]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
4
SRR
Substitute Remote Request — This fixed recessive bit is used only in extended format. It must be set to 1 by
the user for transmission buffers and is stored as received on the CAN bus for receive buffers.
3
IDE
ID Extended — This flag indicates whether the extended or standard identifier format is applied in this buffer. In
the case of a receive buffer, the flag is set as received and indicates to the CPU how to process the buffer
identifier registers. In the case of a transmit buffer, the flag indicates to the MSCAN what type of identifier to send.
0 Standard format (11 bit)
1 Extended format (29 bit)
2-0
ID[17:15]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
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Module Base + 0x00X2
7
6
5
4
3
2
1
0
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-28. Identifier Register 2 (IDR2) — Extended Identifier Mapping
Table 14-29. IDR2 Register Field Descriptions — Extended
Field
Description
7-0
ID[14:7]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
Module Base + 0x00X3
7
6
5
4
3
2
1
0
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-29. Identifier Register 3 (IDR3) — Extended Identifier Mapping
Table 14-30. IDR3 Register Field Descriptions — Extended
Field
Description
7-1
ID[6:0]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
0
RTR
Remote Transmission Request — This flag reflects the status of the remote transmission request bit in the
CAN frame. In the case of a receive buffer, it indicates the status of the received frame and supports the
transmission of an answering frame in software. In the case of a transmit buffer, this flag defines the setting of
the RTR bit to be sent.
0 Data frame
1 Remote frame
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3.3.1.2
IDR0–IDR3 for Standard Identifier Mapping
Module Base + 0x00X0
7
6
5
4
3
2
1
0
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-30. Identifier Register 0 — Standard Mapping
Table 14-31. IDR0 Register Field Descriptions — Standard
Field
Description
7-0
ID[10:3]
Standard Format Identifier — The identifiers consist of 11 bits (ID[10:0]) for the standard format. ID10 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number. See also ID bits in Table 14-32.
Module Base + 0x00X1
7
6
5
4
3
ID2
ID1
ID0
RTR
IDE (=0)
x
x
x
x
x
2
1
0
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 14-31. Identifier Register 1 — Standard Mapping
Table 14-32. IDR1 Register Field Descriptions
Field
Description
7-5
ID[2:0]
Standard Format Identifier — The identifiers consist of 11 bits (ID[10:0]) for the standard format. ID10 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number. See also ID bits in Table 14-31.
4
RTR
Remote Transmission Request — This flag reflects the status of the Remote Transmission Request bit in the
CAN frame. In the case of a receive buffer, it indicates the status of the received frame and supports the
transmission of an answering frame in software. In the case of a transmit buffer, this flag defines the setting of
the RTR bit to be sent.
0 Data frame
1 Remote frame
3
IDE
ID Extended — This flag indicates whether the extended or standard identifier format is applied in this buffer. In
the case of a receive buffer, the flag is set as received and indicates to the CPU how to process the buffer
identifier registers. In the case of a transmit buffer, the flag indicates to the MSCAN what type of identifier to send.
0 Standard format (11 bit)
1 Extended format (29 bit)
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Module Base + 0x00X2
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 14-32. Identifier Register 2 — Standard Mapping
Module Base + 0x00X3
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 14-33. Identifier Register 3 — Standard Mapping
14.3.3.2
Data Segment Registers (DSR0-7)
The eight data segment registers, each with bits DB[7:0], contain the data to be transmitted or received.
The number of bytes to be transmitted or received is determined by the data length code in the
corresponding DLR register.
Module Base + 0x00X4 to Module Base + 0x00XB
7
6
5
4
3
2
1
0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 14-34. Data Segment Registers (DSR0–DSR7) — Extended Identifier Mapping
Table 14-33. DSR0–DSR7 Register Field Descriptions
Field
7-0
DB[7:0]
Description
Data bits 7-0
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.3.3.3
Data Length Register (DLR)
This register keeps the data length field of the CAN frame.
Module Base + 0x00XC
7
6
5
4
3
2
1
0
DLC3
DLC2
DLC1
DLC0
x
x
x
x
R
W
Reset:
x
x
x
x
= Unused; always read “x”
Figure 14-35. Data Length Register (DLR) — Extended Identifier Mapping
Table 14-34. DLR Register Field Descriptions
Field
Description
3-0
DLC[3:0]
Data Length Code Bits — The data length code contains the number of bytes (data byte count) of the respective
message. During the transmission of a remote frame, the data length code is transmitted as programmed while
the number of transmitted data bytes is always 0. The data byte count ranges from 0 to 8 for a data frame.
Table 14-35 shows the effect of setting the DLC bits.
Table 14-35. Data Length Codes
Data Length Code
14.3.3.4
DLC3
DLC2
DLC1
DLC0
Data Byte
Count
0
0
0
0
0
0
0
0
1
1
0
0
1
0
2
0
0
1
1
3
0
1
0
0
4
0
1
0
1
5
0
1
1
0
6
0
1
1
1
7
1
0
0
0
8
Transmit Buffer Priority Register (TBPR)
This register defines the local priority of the associated message buffer. The local priority is used for the
internal prioritization process of the MSCAN and is defined to be highest for the smallest binary number.
The MSCAN implements the following internal prioritization mechanisms:
• All transmission buffers with a cleared TXEx flag participate in the prioritization immediately
before the SOF (start of frame) is sent.
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•
The transmission buffer with the lowest local priority field wins the prioritization.
In cases of more than one buffer having the same lowest priority, the message buffer with the lower index
number wins.
Access: User read/write(1)
Module Base + 0x00XD
7
6
5
4
3
2
1
0
PRIO7
PRIO6
PRIO5
PRIO4
PRIO3
PRIO2
PRIO1
PRIO0
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 14-36. Transmit Buffer Priority Register (TBPR)
1. Read: Anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
14.3.3.5
Time Stamp Register (TSRH–TSRL)
If the TIME bit is enabled, the MSCAN will write a time stamp to the respective registers in the active
transmit or receive buffer right after the EOF of a valid message on the CAN bus (see Section 14.3.2.1,
“MSCAN Control Register 0 (CANCTL0)”). In case of a transmission, the CPU can only read the time
stamp after the respective transmit buffer has been flagged empty.
The timer value, which is used for stamping, is taken from a free running internal CAN bit clock. A timer
overrun is not indicated by the MSCAN. The timer is reset (all bits set to 0) during initialization mode. The
CPU can only read the time stamp registers.
Access: User read/write(1)
Module Base + 0x00XE
R
7
6
5
4
3
2
1
0
TSR15
TSR14
TSR13
TSR12
TSR11
TSR10
TSR9
TSR8
x
x
x
x
x
x
x
x
W
Reset:
Figure 14-37. Time Stamp Register — High Byte (TSRH)
1. Read: Anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Unimplemented
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
Access: User read/write(1)
Module Base + 0x00XF
R
7
6
5
4
3
2
1
0
TSR7
TSR6
TSR5
TSR4
TSR3
TSR2
TSR1
TSR0
x
x
x
x
x
x
x
x
W
Reset:
Figure 14-38. Time Stamp Register — Low Byte (TSRL)
1. Read: Anytime when TXEx flag is set (see Section 14.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Unimplemented
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
14.4
14.4.1
Functional Description
General
This section provides a complete functional description of the MSCAN.
14.4.2
Message Storage
CAN Receive / Transmit Engine
Memory Mapped I/O
Rx0
RXF
Receiver
TxBG
Tx0
MSCAN
TxFG
Tx1
TxBG
Tx2
Transmitter
CPU bus
RxFG
RxBG
MSCAN
Rx1
Rx2
Rx3
Rx4
TXE0
PRIO
TXE1
CPU bus
PRIO
TXE2
PRIO
Figure 14-39. User Model for Message Buffer Organization
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
The MSCAN facilitates a sophisticated message storage system which addresses the requirements of a
broad range of network applications.
14.4.2.1
Message Transmit Background
Modern application layer software is built upon two fundamental assumptions:
• Any CAN node is able to send out a stream of scheduled messages without releasing the CAN bus
between the two messages. Such nodes arbitrate for the CAN bus immediately after sending the
previous message and only release the CAN bus in case of lost arbitration.
• The internal message queue within any CAN node is organized such that the highest priority
message is sent out first, if more than one message is ready to be sent.
The behavior described in the bullets above cannot be achieved with a single transmit buffer. That buffer
must be reloaded immediately after the previous message is sent. This loading process lasts a finite amount
of time and must be completed within the inter-frame sequence (IFS) to be able to send an uninterrupted
stream of messages. Even if this is feasible for limited CAN bus speeds, it requires that the CPU reacts
with short latencies to the transmit interrupt.
A double buffer scheme de-couples the reloading of the transmit buffer from the actual message sending
and, therefore, reduces the reactiveness requirements of the CPU. Problems can arise if the sending of a
message is finished while the CPU re-loads the second buffer. No buffer would then be ready for
transmission, and the CAN bus would be released.
At least three transmit buffers are required to meet the first of the above requirements under all
circumstances. The MSCAN has three transmit buffers.
The second requirement calls for some sort of internal prioritization which the MSCAN implements with
the “local priority” concept described in Section 14.4.2.2, “Transmit Structures.”
14.4.2.2
Transmit Structures
The MSCAN triple transmit buffer scheme optimizes real-time performance by allowing multiple
messages to be set up in advance. The three buffers are arranged as shown in Figure 14-39.
All three buffers have a 13-byte data structure similar to the outline of the receive buffers (see
Section 14.3.3, “Programmer’s Model of Message Storage”). An additional Transmit Buffer Priority
Register (TBPR) contains an 8-bit local priority field (PRIO) (see Section 14.3.3.4, “Transmit Buffer
Priority Register (TBPR)”). The remaining two bytes are used for time stamping of a message, if required
(see Section 14.3.3.5, “Time Stamp Register (TSRH–TSRL)”).
To transmit a message, the CPU must identify an available transmit buffer, which is indicated by a set
transmitter buffer empty (TXEx) flag (see Section 14.3.2.7, “MSCAN Transmitter Flag Register
(CANTFLG)”). If a transmit buffer is available, the CPU must set a pointer to this buffer by writing to the
CANTBSEL register (see Section 14.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”). This makes the respective buffer accessible within the CANTXFG address space (see
Section 14.3.3, “Programmer’s Model of Message Storage”). The algorithmic feature associated with the
CANTBSEL register simplifies the transmit buffer selection. In addition, this scheme makes the handler
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software simpler because only one address area is applicable for the transmit process, and the required
address space is minimized.
The CPU then stores the identifier, the control bits, and the data content into one of the transmit buffers.
Finally, the buffer is flagged as ready for transmission by clearing the associated TXE flag.
The MSCAN then schedules the message for transmission and signals the successful transmission of the
buffer by setting the associated TXE flag. A transmit interrupt (see Section 14.4.7.2, “Transmit Interrupt”)
is generated1 when TXEx is set and can be used to drive the application software to re-load the buffer.
If more than one buffer is scheduled for transmission when the CAN bus becomes available for arbitration,
the MSCAN uses the local priority setting of the three buffers to determine the prioritization. For this
purpose, every transmit buffer has an 8-bit local priority field (PRIO). The application software programs
this field when the message is set up. The local priority reflects the priority of this particular message
relative to the set of messages being transmitted from this node. The lowest binary value of the PRIO field
is defined to be the highest priority. The internal scheduling process takes place whenever the MSCAN
arbitrates for the CAN bus. This is also the case after the occurrence of a transmission error.
When a high priority message is scheduled by the application software, it may become necessary to abort
a lower priority message in one of the three transmit buffers. Because messages that are already in
transmission cannot be aborted, the user must request the abort by setting the corresponding abort request
bit (ABTRQ) (see Section 14.3.2.9, “MSCAN Transmitter Message Abort Request Register
(CANTARQ)”.) The MSCAN then grants the request, if possible, by:
1. Setting the corresponding abort acknowledge flag (ABTAK) in the CANTAAK register.
2. Setting the associated TXE flag to release the buffer.
3. Generating a transmit interrupt. The transmit interrupt handler software can determine from the
setting of the ABTAK flag whether the message was aborted (ABTAK = 1) or sent (ABTAK = 0).
14.4.2.3
Receive Structures
The received messages are stored in a five stage input FIFO. The five message buffers are alternately
mapped into a single memory area (see Figure 14-39). The background receive buffer (RxBG) is
exclusively associated with the MSCAN, but the foreground receive buffer (RxFG) is addressable by the
CPU (see Figure 14-39). This scheme simplifies the handler software because only one address area is
applicable for the receive process.
All receive buffers have a size of 15 bytes to store the CAN control bits, the identifier (standard or
extended), the data contents, and a time stamp, if enabled (see Section 14.3.3, “Programmer’s Model of
Message Storage”).
The receiver full flag (RXF) (see Section 14.3.2.5, “MSCAN Receiver Flag Register (CANRFLG)”)
signals the status of the foreground receive buffer. When the buffer contains a correctly received message
with a matching identifier, this flag is set.
On reception, each message is checked to see whether it passes the filter (see Section 14.4.3, “Identifier
Acceptance Filter”) and simultaneously is written into the active RxBG. After successful reception of a
valid message, the MSCAN shifts the content of RxBG into the receiver FIFO, sets the RXF flag, and
1. The transmit interrupt occurs only if not masked. A polling scheme can be applied on TXEx also.
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generates a receive interrupt1 (see Section 14.4.7.3, “Receive Interrupt”) to the CPU. The user’s receive
handler must read the received message from the RxFG and then reset the RXF flag to acknowledge the
interrupt and to release the foreground buffer. A new message, which can follow immediately after the IFS
field of the CAN frame, is received into the next available RxBG. If the MSCAN receives an invalid
message in its RxBG (wrong identifier, transmission errors, etc.) the actual contents of the buffer will be
over-written by the next message. The buffer will then not be shifted into the FIFO.
When the MSCAN module is transmitting, the MSCAN receives its own transmitted messages into the
background receive buffer, RxBG, but does not shift it into the receiver FIFO, generate a receive interrupt,
or acknowledge its own messages on the CAN bus. The exception to this rule is in loopback mode (see
Section 14.3.2.2, “MSCAN Control Register 1 (CANCTL1)”) where the MSCAN treats its own messages
exactly like all other incoming messages. The MSCAN receives its own transmitted messages in the event
that it loses arbitration. If arbitration is lost, the MSCAN must be prepared to become a receiver.
An overrun condition occurs when all receive message buffers in the FIFO are filled with correctly
received messages with accepted identifiers and another message is correctly received from the CAN bus
with an accepted identifier. The latter message is discarded and an error interrupt with overrun indication
is generated if enabled (see Section 14.4.7.5, “Error Interrupt”). The MSCAN remains able to transmit
messages while the receiver FIFO is being filled, but all incoming messages are discarded. As soon as a
receive buffer in the FIFO is available again, new valid messages will be accepted.
14.4.3
Identifier Acceptance Filter
The MSCAN identifier acceptance registers (see Section 14.3.2.12, “MSCAN Identifier Acceptance
Control Register (CANIDAC)”) define the acceptable patterns of the standard or extended identifier
(ID[10:0] or ID[28:0]). Any of these bits can be marked ‘don’t care’ in the MSCAN identifier mask
registers (see Section 14.3.2.18, “MSCAN Identifier Mask Registers (CANIDMR0–CANIDMR7)”).
A filter hit is indicated to the application software by a set receive buffer full flag (RXF = 1) and three bits
in the CANIDAC register (see Section 14.3.2.12, “MSCAN Identifier Acceptance Control Register
(CANIDAC)”). These identifier hit flags (IDHIT[2:0]) clearly identify the filter section that caused the
acceptance. They simplify the application software’s task to identify the cause of the receiver interrupt. If
more than one hit occurs (two or more filters match), the lower hit has priority.
A very flexible programmable generic identifier acceptance filter has been introduced to reduce the CPU
interrupt loading. The filter is programmable to operate in four different modes:
• Two identifier acceptance filters, each to be applied to:
— The full 29 bits of the extended identifier and to the following bits of the CAN 2.0B frame:
– Remote transmission request (RTR)
– Identifier extension (IDE)
– Substitute remote request (SRR)
— The 11 bits of the standard identifier plus the RTR and IDE bits of the CAN 2.0A/B messages.
This mode implements two filters for a full length CAN 2.0B compliant extended identifier.
Although this mode can be used for standard identifiers, it is recommended to use the four or
eight identifier acceptance filters.
1. The receive interrupt occurs only if not masked. A polling scheme can be applied on RXF also.
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•
•
•
Figure 14-40 shows how the first 32-bit filter bank (CANIDAR0–CANIDAR3,
CANIDMR0–CANIDMR3) produces a filter 0 hit. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces a filter 1 hit.
Four identifier acceptance filters, each to be applied to:
— The 14 most significant bits of the extended identifier plus the SRR and IDE bits of CAN 2.0B
messages.
— The 11 bits of the standard identifier, the RTR and IDE bits of CAN 2.0A/B messages.
Figure 14-41 shows how the first 32-bit filter bank (CANIDAR0–CANIDAR3,
CANIDMR0–CANIDMR3) produces filter 0 and 1 hits. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces filter 2 and 3 hits.
Eight identifier acceptance filters, each to be applied to the first 8 bits of the identifier. This mode
implements eight independent filters for the first 8 bits of a CAN 2.0A/B compliant standard
identifier or a CAN 2.0B compliant extended identifier.
Figure 14-42 shows how the first 32-bit filter bank (CANIDAR0–CANIDAR3,
CANIDMR0–CANIDMR3) produces filter 0 to 3 hits. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces filter 4 to 7 hits.
Closed filter. No CAN message is copied into the foreground buffer RxFG, and the RXF flag is
never set.
CAN 2.0B
Extended Identifier ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier ID10
IDR0
ID3
ID2
IDR1
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
AM7
CANIDMR0
AM0
AM7
CANIDMR1
AM0
AM7
CANIDMR2
AM0
AM7
CANIDMR3
AM0
AC7
CANIDAR0
AC0
AC7
CANIDAR1
AC0
AC7
CANIDAR2
AC0
AC7
CANIDAR3
AC0
ID Accepted (Filter 0 Hit)
Figure 14-40. 32-bit Maskable Identifier Acceptance Filter
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Chapter 14 Freescale’s Scalable Controller Area Network (S12MSCANV3)
CAN 2.0B
Extended Identifier
ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier
ID10
IDR0
ID3
ID2
IDR1
AM7
CANIDMR0
AM0
AM7
CANIDMR1
AM0
AC7
CANIDAR0
AC0
AC7
CANIDAR1
AC0
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
ID Accepted (Filter 0 Hit)
AM7
CANIDMR2
AM0
AM7
CANIDMR3
AM0
AC7
CANIDAR2
AC0
AC7
CANIDAR3
AC0
ID Accepted (Filter 1 Hit)
Figure 14-41. 16-bit Maskable Identifier Acceptance Filters
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CAN 2.0B
Extended Identifier ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier ID10
IDR0
ID3
ID2
IDR1
AM7
CIDMR0
AM0
AC7
CIDAR0
AC0
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
ID Accepted (Filter 0 Hit)
AM7
CIDMR1
AM0
AC7
CIDAR1
AC0
ID Accepted (Filter 1 Hit)
AM7
CIDMR2
AM0
AC7
CIDAR2
AC0
ID Accepted (Filter 2 Hit)
AM7
CIDMR3
AM0
AC7
CIDAR3
AC0
ID Accepted (Filter 3 Hit)
Figure 14-42. 8-bit Maskable Identifier Acceptance Filters
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14.4.3.1
Protocol Violation Protection
The MSCAN protects the user from accidentally violating the CAN protocol through programming errors.
The protection logic implements the following features:
• The receive and transmit error counters cannot be written or otherwise manipulated.
• All registers which control the configuration of the MSCAN cannot be modified while the MSCAN
is on-line. The MSCAN has to be in Initialization Mode. The corresponding INITRQ/INITAK
handshake bits in the CANCTL0/CANCTL1 registers (see Section 14.3.2.1, “MSCAN Control
Register 0 (CANCTL0)”) serve as a lock to protect the following registers:
— MSCAN control 1 register (CANCTL1)
— MSCAN bus timing registers 0 and 1 (CANBTR0, CANBTR1)
— MSCAN identifier acceptance control register (CANIDAC)
— MSCAN identifier acceptance registers (CANIDAR0–CANIDAR7)
— MSCAN identifier mask registers (CANIDMR0–CANIDMR7)
• The TXCAN is immediately forced to a recessive state when the MSCAN goes into the power
down mode or initialization mode (see Section 14.4.5.6, “MSCAN Power Down Mode,” and
Section 14.4.4.5, “MSCAN Initialization Mode”).
• The MSCAN enable bit (CANE) is writable only once in normal system operation modes, which
provides further protection against inadvertently disabling the MSCAN.
14.4.3.2
Clock System
Figure 14-43 shows the structure of the MSCAN clock generation circuitry.
MSCAN
Bus Clock
CANCLK
CLKSRC
Prescaler
(1 .. 64)
Time quanta clock (Tq)
CLKSRC
Oscillator Clock
Figure 14-43. MSCAN Clocking Scheme
The clock source bit (CLKSRC) in the CANCTL1 register (14.3.2.2/14-515) defines whether the internal
CANCLK is connected to the output of a crystal oscillator (oscillator clock) or to the bus clock.
The clock source has to be chosen such that the tight oscillator tolerance requirements (up to 0.4%) of the
CAN protocol are met. Additionally, for high CAN bus rates (1 Mbps), a 45% to 55% duty cycle of the
clock is required.
If the bus clock is generated from a PLL, it is recommended to select the oscillator clock rather than the
bus clock due to jitter considerations, especially at the faster CAN bus rates.
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For microcontrollers without a clock and reset generator (CRG), CANCLK is driven from the crystal
oscillator (oscillator clock).
A programmable prescaler generates the time quanta (Tq) clock from CANCLK. A time quantum is the
atomic unit of time handled by the MSCAN.
Eqn. 14-2
f CANCLK
=
----------------------------------------------------Tq ( Prescaler value -)
A bit time is subdivided into three segments as described in the Bosch CAN 2.0A/B specification. (see
Figure 14-44):
• SYNC_SEG: This segment has a fixed length of one time quantum. Signal edges are expected to
happen within this section.
• Time Segment 1: This segment includes the PROP_SEG and the PHASE_SEG1 of the CAN
standard. It can be programmed by setting the parameter TSEG1 to consist of 4 to 16 time quanta.
• Time Segment 2: This segment represents the PHASE_SEG2 of the CAN standard. It can be
programmed by setting the TSEG2 parameter to be 2 to 8 time quanta long.
Eqn. 14-3
f Tq
Bit Rate = --------------------------------------------------------------------------------( number of Time Quanta )
NRZ Signal
SYNC_SEG
Time Segment 1
(PROP_SEG + PHASE_SEG1)
Time Segment 2
(PHASE_SEG2)
1
4 ... 16
2 ... 8
8 ... 25 Time Quanta
= 1 Bit Time
Transmit Point
Sample Point
(single or triple sampling)
Figure 14-44. Segments within the Bit Time
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Table 14-36. Time Segment Syntax
Syntax
Description
System expects transitions to occur on the CAN bus during this
period.
SYNC_SEG
Transmit Point
A node in transmit mode transfers a new value to the CAN bus at
this point.
Sample Point
A node in receive mode samples the CAN bus at this point. If the
three samples per bit option is selected, then this point marks the
position of the third sample.
The synchronization jump width (see the Bosch CAN 2.0A/B specification for details) can be programmed
in a range of 1 to 4 time quanta by setting the SJW parameter.
The SYNC_SEG, TSEG1, TSEG2, and SJW parameters are set by programming the MSCAN bus timing
registers (CANBTR0, CANBTR1) (see Section 14.3.2.3, “MSCAN Bus Timing Register 0 (CANBTR0)”
and Section 14.3.2.4, “MSCAN Bus Timing Register 1 (CANBTR1)”).
Table 14-37 gives an overview of the Bosch CAN 2.0A/B specification compliant segment settings and the
related parameter values.
NOTE
It is the user’s responsibility to ensure the bit time settings are in compliance
with the CAN standard.
Table 14-37. Bosch CAN 2.0A/B Compliant Bit Time Segment Settings
Synchronization
Jump Width
Time Segment 1
TSEG1
Time Segment 2
TSEG2
5 .. 10
4 .. 9
2
1
1 .. 2
0 .. 1
4 .. 11
3 .. 10
3
2
1 .. 3
0 .. 2
5 .. 12
4 .. 11
4
3
1 .. 4
0 .. 3
6 .. 13
5 .. 12
5
4
1 .. 4
0 .. 3
7 .. 14
6 .. 13
6
5
1 .. 4
0 .. 3
8 .. 15
7 .. 14
7
6
1 .. 4
0 .. 3
9 .. 16
8 .. 15
8
7
1 .. 4
0 .. 3
14.4.4
14.4.4.1
SJW
Modes of Operation
Normal System Operating Modes
The MSCAN module behaves as described within this specification in all normal system operating modes.
Write restrictions exist for some registers.
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14.4.4.2
Special System Operating Modes
The MSCAN module behaves as described within this specification in all special system operating modes.
Write restrictions which exist on specific registers in normal modes are lifted for test purposes in special
modes.
14.4.4.3
Emulation Modes
In all emulation modes, the MSCAN module behaves just like in normal system operating modes as
described within this specification.
14.4.4.4
Listen-Only Mode
In an optional CAN bus monitoring mode (listen-only), the CAN node is able to receive valid data frames
and valid remote frames, but it sends only “recessive” bits on the CAN bus. In addition, it cannot start a
transmission.
If the MAC sub-layer is required to send a “dominant” bit (ACK bit, overload flag, or active error flag), the
bit is rerouted internally so that the MAC sub-layer monitors this “dominant” bit, although the CAN bus
may remain in recessive state externally.
14.4.4.5
MSCAN Initialization Mode
The MSCAN enters initialization mode when it is enabled (CANE=1).
When entering initialization mode during operation, any on-going transmission or reception is
immediately aborted and synchronization to the CAN bus is lost, potentially causing CAN protocol
violations. To protect the CAN bus system from fatal consequences of violations, the MSCAN
immediately drives TXCAN into a recessive state.
NOTE
The user is responsible for ensuring that the MSCAN is not active when
initialization mode is entered. The recommended procedure is to bring the
MSCAN into sleep mode (SLPRQ = 1 and SLPAK = 1) before setting the
INITRQ bit in the CANCTL0 register. Otherwise, the abort of an on-going
message can cause an error condition and can impact other CAN bus
devices.
In initialization mode, the MSCAN is stopped. However, interface registers remain accessible. This mode
is used to reset the CANCTL0, CANRFLG, CANRIER, CANTFLG, CANTIER, CANTARQ,
CANTAAK, and CANTBSEL registers to their default values. In addition, the MSCAN enables the
configuration of the CANBTR0, CANBTR1 bit timing registers; CANIDAC; and the CANIDAR,
CANIDMR message filters. See Section 14.3.2.1, “MSCAN Control Register 0 (CANCTL0),” for a
detailed description of the initialization mode.
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Bus Clock Domain
CAN Clock Domain
INITRQ
SYNC
sync.
INITRQ
sync.
SYNC
INITAK
CPU
Init Request
INITAK
Flag
INITAK
INIT
Flag
Figure 14-45. Initialization Request/Acknowledge Cycle
Due to independent clock domains within the MSCAN, INITRQ must be synchronized to all domains by
using a special handshake mechanism. This handshake causes additional synchronization delay (see
Figure 14-45).
If there is no message transfer ongoing on the CAN bus, the minimum delay will be two additional bus
clocks and three additional CAN clocks. When all parts of the MSCAN are in initialization mode, the
INITAK flag is set. The application software must use INITAK as a handshake indication for the request
(INITRQ) to go into initialization mode.
NOTE
The CPU cannot clear INITRQ before initialization mode (INITRQ = 1 and
INITAK = 1) is active.
14.4.5
Low-Power Options
If the MSCAN is disabled (CANE = 0), the MSCAN clocks are stopped for power saving.
If the MSCAN is enabled (CANE = 1), the MSCAN has two additional modes with reduced power
consumption, compared to normal mode: sleep and power down mode. In sleep mode, power consumption
is reduced by stopping all clocks except those to access the registers from the CPU side. In power down
mode, all clocks are stopped and no power is consumed.
Table 14-38 summarizes the combinations of MSCAN and CPU modes. A particular combination of
modes is entered by the given settings on the CSWAI and SLPRQ/SLPAK bits.
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Table 14-38. CPU vs. MSCAN Operating Modes
MSCAN Mode
Reduced Power Consumption
CPU Mode
Normal
Sleep
RUN
CSWAI = X(1)
SLPRQ = 0
SLPAK = 0
CSWAI = X
SLPRQ = 1
SLPAK = 1
WAIT
CSWAI = 0
SLPRQ = 0
SLPAK = 0
CSWAI = 0
SLPRQ = 1
SLPAK = 1
STOP
Power Down
Disabled
(CANE=0)
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = 1
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
1. ‘X’ means don’t care.
14.4.5.1
Operation in Run Mode
As shown in Table 14-38, only MSCAN sleep mode is available as low power option when the CPU is in
run mode.
14.4.5.2
Operation in Wait Mode
The WAI instruction puts the MCU in a low power consumption stand-by mode. If the CSWAI bit is set,
additional power can be saved in power down mode because the CPU clocks are stopped. After leaving
this power down mode, the MSCAN restarts and enters normal mode again.
While the CPU is in wait mode, the MSCAN can be operated in normal mode and generate interrupts
(registers can be accessed via background debug mode).
14.4.5.3
Operation in Stop Mode
The STOP instruction puts the MCU in a low power consumption stand-by mode. In stop mode, the
MSCAN is set in power down mode regardless of the value of the SLPRQ/SLPAK and CSWAI bits
(Table 14-38).
14.4.5.4
MSCAN Normal Mode
This is a non-power-saving mode. Enabling the MSCAN puts the module from disabled mode into normal
mode. In this mode the module can either be in initialization mode or out of initialization mode. See
Section 14.4.4.5, “MSCAN Initialization Mode”.
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14.4.5.5
MSCAN Sleep Mode
The CPU can request the MSCAN to enter this low power mode by asserting the SLPRQ bit in the
CANCTL0 register. The time when the MSCAN enters sleep mode depends on a fixed synchronization
delay and its current activity:
• If there are one or more message buffers scheduled for transmission (TXEx = 0), the MSCAN will
continue to transmit until all transmit message buffers are empty (TXEx = 1, transmitted
successfully or aborted) and then goes into sleep mode.
• If the MSCAN is receiving, it continues to receive and goes into sleep mode as soon as the CAN
bus next becomes idle.
• If the MSCAN is neither transmitting nor receiving, it immediately goes into sleep mode.
Bus Clock Domain
CAN Clock Domain
SLPRQ
SYNC
sync.
SLPRQ
sync.
SYNC
SLPAK
CPU
Sleep Request
SLPAK
Flag
SLPAK
SLPRQ
Flag
MSCAN
in Sleep Mode
Figure 14-46. Sleep Request / Acknowledge Cycle
NOTE
The application software must avoid setting up a transmission (by clearing
one or more TXEx flag(s)) and immediately request sleep mode (by setting
SLPRQ). Whether the MSCAN starts transmitting or goes into sleep mode
directly depends on the exact sequence of operations.
If sleep mode is active, the SLPRQ and SLPAK bits are set (Figure 14-46). The application software must
use SLPAK as a handshake indication for the request (SLPRQ) to go into sleep mode.
When in sleep mode (SLPRQ = 1 and SLPAK = 1), the MSCAN stops its internal clocks. However, clocks
that allow register accesses from the CPU side continue to run.
If the MSCAN is in bus-off state, it stops counting the 128 occurrences of 11 consecutive recessive bits
due to the stopped clocks. TXCAN remains in a recessive state. If RXF = 1, the message can be read and
RXF can be cleared. Shifting a new message into the foreground buffer of the receiver FIFO (RxFG) does
not take place while in sleep mode.
It is possible to access the transmit buffers and to clear the associated TXE flags. No message abort takes
place while in sleep mode.
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If the WUPE bit in CANCTL0 is not asserted, the MSCAN will mask any activity it detects on CAN.
RXCAN is therefore held internally in a recessive state. This locks the MSCAN in sleep mode. WUPE
must be set before entering sleep mode to take effect.
The MSCAN is able to leave sleep mode (wake up) only when:
• CAN bus activity occurs and WUPE = 1
or
• the CPU clears the SLPRQ bit
NOTE
The CPU cannot clear the SLPRQ bit before sleep mode (SLPRQ = 1 and
SLPAK = 1) is active.
After wake-up, the MSCAN waits for 11 consecutive recessive bits to synchronize to the CAN bus. As a
consequence, if the MSCAN is woken-up by a CAN frame, this frame is not received.
The receive message buffers (RxFG and RxBG) contain messages if they were received before sleep mode
was entered. All pending actions will be executed upon wake-up; copying of RxBG into RxFG, message
aborts and message transmissions. If the MSCAN remains in bus-off state after sleep mode was exited, it
continues counting the 128 occurrences of 11 consecutive recessive bits.
14.4.5.6
MSCAN Power Down Mode
The MSCAN is in power down mode (Table 14-38) when
• CPU is in stop mode
or
• CPU is in wait mode and the CSWAI bit is set
When entering the power down mode, the MSCAN immediately stops all ongoing transmissions and
receptions, potentially causing CAN protocol violations. To protect the CAN bus system from fatal
consequences of violations to the above rule, the MSCAN immediately drives TXCAN into a recessive
state.
NOTE
The user is responsible for ensuring that the MSCAN is not active when
power down mode is entered. The recommended procedure is to bring the
MSCAN into Sleep mode before the STOP or WAI instruction (if CSWAI
is set) is executed. Otherwise, the abort of an ongoing message can cause an
error condition and impact other CAN bus devices.
In power down mode, all clocks are stopped and no registers can be accessed. If the MSCAN was not in
sleep mode before power down mode became active, the module performs an internal recovery cycle after
powering up. This causes some fixed delay before the module enters normal mode again.
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14.4.5.7
Disabled Mode
The MSCAN is in disabled mode out of reset (CANE=0). All module clocks are stopped for power saving,
however the register map can still be accessed as specified.
14.4.5.8
Programmable Wake-Up Function
The MSCAN can be programmed to wake up from sleep or power down mode as soon as CAN bus activity
is detected (see control bit WUPE in MSCAN Control Register 0 (CANCTL0). The sensitivity to existing
CAN bus action can be modified by applying a low-pass filter function to the RXCAN input line (see
control bit WUPM in Section 14.3.2.2, “MSCAN Control Register 1 (CANCTL1)”).
This feature can be used to protect the MSCAN from wake-up due to short glitches on the CAN bus lines.
Such glitches can result from—for example—electromagnetic interference within noisy environments.
14.4.6
Reset Initialization
The reset state of each individual bit is listed in Section 14.3.2, “Register Descriptions,” which details all
the registers and their bit-fields.
14.4.7
Interrupts
This section describes all interrupts originated by the MSCAN. It documents the enable bits and generated
flags. Each interrupt is listed and described separately.
14.4.7.1
Description of Interrupt Operation
The MSCAN supports four interrupt vectors (see Table 14-39), any of which can be individually masked
(for details see Section 14.3.2.6, “MSCAN Receiver Interrupt Enable Register (CANRIER)” to
Section 14.3.2.8, “MSCAN Transmitter Interrupt Enable Register (CANTIER)”).
Refer to the device overview section to determine the dedicated interrupt vector addresses.
Table 14-39. Interrupt Vectors
Interrupt Source
Wake-Up Interrupt (WUPIF)
14.4.7.2
CCR Mask
I bit
Local Enable
CANRIER (WUPIE)
Error Interrupts Interrupt (CSCIF, OVRIF)
I bit
CANRIER (CSCIE, OVRIE)
Receive Interrupt (RXF)
I bit
CANRIER (RXFIE)
Transmit Interrupts (TXE[2:0])
I bit
CANTIER (TXEIE[2:0])
Transmit Interrupt
At least one of the three transmit buffers is empty (not scheduled) and can be loaded to schedule a message
for transmission. The TXEx flag of the empty message buffer is set.
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14.4.7.3
Receive Interrupt
A message is successfully received and shifted into the foreground buffer (RxFG) of the receiver FIFO.
This interrupt is generated immediately after receiving the EOF symbol. The RXF flag is set. If there are
multiple messages in the receiver FIFO, the RXF flag is set as soon as the next message is shifted to the
foreground buffer.
14.4.7.4
Wake-Up Interrupt
A wake-up interrupt is generated if activity on the CAN bus occurs during MSCAN sleep or power-down
mode.
NOTE
This interrupt can only occur if the MSCAN was in sleep mode (SLPRQ = 1
and SLPAK = 1) before entering power down mode, the wake-up option is
enabled (WUPE = 1), and the wake-up interrupt is enabled (WUPIE = 1).
14.4.7.5
Error Interrupt
An error interrupt is generated if an overrun of the receiver FIFO, error, warning, or bus-off condition
occurrs. MSCAN Receiver Flag Register (CANRFLG) indicates one of the following conditions:
• Overrun — An overrun condition of the receiver FIFO as described in Section 14.4.2.3, “Receive
Structures,” occurred.
• CAN Status Change — The actual value of the transmit and receive error counters control the
CAN bus state of the MSCAN. As soon as the error counters skip into a critical range (Tx/Rxwarning, Tx/Rx-error, bus-off) the MSCAN flags an error condition. The status change, which
caused the error condition, is indicated by the TSTAT and RSTAT flags (see Section 14.3.2.5,
“MSCAN Receiver Flag Register (CANRFLG)” and Section 14.3.2.6, “MSCAN Receiver
Interrupt Enable Register (CANRIER)”).
14.4.7.6
Interrupt Acknowledge
Interrupts are directly associated with one or more status flags in either the MSCAN Receiver Flag Register
(CANRFLG) or the MSCAN Transmitter Flag Register (CANTFLG). Interrupts are pending as long as
one of the corresponding flags is set. The flags in CANRFLG and CANTFLG must be reset within the
interrupt handler to handshake the interrupt. The flags are reset by writing a 1 to the corresponding bit
position. A flag cannot be cleared if the respective condition prevails.
NOTE
It must be guaranteed that the CPU clears only the bit causing the current
interrupt. For this reason, bit manipulation instructions (BSET) must not be
used to clear interrupt flags. These instructions may cause accidental
clearing of interrupt flags which are set after entering the current interrupt
service routine.
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14.5
14.5.1
Initialization/Application Information
MSCAN initialization
The procedure to initially start up the MSCAN module out of reset is as follows:
1. Assert CANE
2. Write to the configuration registers in initialization mode
3. Clear INITRQ to leave initialization mode
If the configuration of registers which are only writable in initialization mode shall be changed:
1. Bring the module into sleep mode by setting SLPRQ and awaiting SLPAK to assert after the CAN
bus becomes idle.
2. Enter initialization mode: assert INITRQ and await INITAK
3. Write to the configuration registers in initialization mode
4. Clear INITRQ to leave initialization mode and continue
14.5.2
Bus-Off Recovery
The bus-off recovery is user configurable. The bus-off state can either be left automatically or on user
request.
For reasons of backwards compatibility, the MSCAN defaults to automatic recovery after reset. In this
case, the MSCAN will become error active again after counting 128 occurrences of 11 consecutive
recessive bits on the CAN bus (see the Bosch CAN 2.0 A/B specification for details).
If the MSCAN is configured for user request (BORM set in MSCAN Control Register 1 (CANCTL1)), the
recovery from bus-off starts after both independent events have become true:
• 128 occurrences of 11 consecutive recessive bits on the CAN bus have been monitored
• BOHOLD in MSCAN Miscellaneous Register (CANMISC) has been cleared by the user
These two events may occur in any order.
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Chapter 15
Serial Communication Interface (S12SCIV5)
Table 15-1. Revision History
Version Revision Effective
Number
Date
Date
05.03 12/25/2008
Author
Description of Changes
05.04
08/05/2009
remove redundancy comments in Figure1-2
fix typo, SCIBDL reset value be 0x04, not 0x00
05.05
06/03/2010
fix typo, Table 15-4,SCICR1 Even parity should be PT=0
fix typo, on page 15-583,should be BKDIF,not BLDIF
15.1
Introduction
This block guide provides an overview of the serial communication interface (SCI) module.
The SCI allows asynchronous serial communications with peripheral devices and other CPUs.
15.1.1
Glossary
IR: InfraRed
IrDA: Infrared Design Associate
IRQ: Interrupt Request
LIN: Local Interconnect Network
LSB: Least Significant Bit
MSB: Most Significant Bit
NRZ: Non-Return-to-Zero
RZI: Return-to-Zero-Inverted
RXD: Receive Pin
SCI : Serial Communication Interface
TXD: Transmit Pin
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15.1.2
Features
The SCI includes these distinctive features:
• Full-duplex or single-wire operation
• Standard mark/space non-return-to-zero (NRZ) format
• Selectable IrDA 1.4 return-to-zero-inverted (RZI) format with programmable pulse widths
• 13-bit baud rate selection
• Programmable 8-bit or 9-bit data format
• Separately enabled transmitter and receiver
• Programmable polarity for transmitter and receiver
• Programmable transmitter output parity
• Two receiver wakeup methods:
— Idle line wakeup
— Address mark wakeup
• Interrupt-driven operation with eight flags:
— Transmitter empty
— Transmission complete
— Receiver full
— Idle receiver input
— Receiver overrun
— Noise error
— Framing error
— Parity error
— Receive wakeup on active edge
— Transmit collision detect supporting LIN
— Break Detect supporting LIN
• Receiver framing error detection
• Hardware parity checking
• 1/16 bit-time noise detection
15.1.3
Modes of Operation
The SCI functions the same in normal, special, and emulation modes. It has two low power modes, wait
and stop modes.
• Run mode
• Wait mode
• Stop mode
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15.1.4
Block Diagram
Figure 15-1 is a high level block diagram of the SCI module, showing the interaction of various function
blocks.
SCI Data Register
RXD Data In
Infrared
Decoder
Receive Shift Register
Receive & Wakeup
Control
Bus Clock
Baud Rate
Generator
IDLE
Receive
RDRF/OR
Interrupt
Generation BRKD
RXEDG
BERR
Data Format Control
1/16
Transmit Control
Transmit Shift Register
SCI
Interrupt
Request
Transmit
TDRE
Interrupt
Generation TC
Infrared
Encoder
Data Out TXD
SCI Data Register
Figure 15-1. SCI Block Diagram
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15.2
External Signal Description
The SCI module has a total of two external pins.
15.2.1
TXD — Transmit Pin
The TXD pin transmits SCI (standard or infrared) data. It will idle high in either mode and is high
impedance anytime the transmitter is disabled.
15.2.2
RXD — Receive Pin
The RXD pin receives SCI (standard or infrared) data. An idle line is detected as a line high. This input is
ignored when the receiver is disabled and should be terminated to a known voltage.
15.3
Memory Map and Register Definition
This section provides a detailed description of all the SCI registers.
15.3.1
Module Memory Map and Register Definition
The memory map for the SCI module is given below in Figure 15-2. The address listed for each register is
the address offset. The total address for each register is the sum of the base address for the SCI module and
the address offset for each register.
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15.3.2
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Writes to a reserved register locations do not have any effect
and reads of these locations return a zero. Details of register bit and field function follow the register
diagrams, in bit order.
Register
Name
0x0000
SCIBDH1
W
0x0001
SCIBDL1
W
0x0002
SCICR11
R
R
R
W
0x0000
SCIASR12
W
0x0001
SCIACR12
W
0x0002
SCIACR22
0x0003
SCICR2
0x0004
SCISR1
0x0005
SCISR2
0x0006
SCIDRH
0x0007
SCIDRL
R
R
Bit 7
6
5
4
3
2
1
Bit 0
IREN
TNP1
TNP0
SBR12
SBR11
SBR10
SBR9
SBR8
SBR7
SBR6
SBR5
SBR4
SBR3
SBR2
SBR1
SBR0
LOOPS
SCISWAI
RSRC
M
WAKE
ILT
PE
PT
0
0
0
0
BERRV
BERRIF
BKDIF
0
0
0
0
BERRIE
BKDIE
0
0
0
0
0
BERRM1
BERRM0
BKDFE
TIE
TCIE
RIE
ILIE
TE
RE
RWU
SBK
TDRE
TC
RDRF
IDLE
OR
NF
FE
PF
0
0
TXPOL
RXPOL
BRK13
TXDIR
0
0
0
0
0
0
RXEDGIF
RXEDGIE
R
W
R
W
R
0
W
R
W
R
AMAP
R8
W
T8
RAF
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
1.These registers are accessible if the AMAP bit in the SCISR2 register is set to zero.
2,These registers are accessible if the AMAP bit in the SCISR2 register is set to one.
= Unimplemented or Reserved
Figure 15-2. SCI Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
565
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.1
SCI Baud Rate Registers (SCIBDH, SCIBDL)
Module Base + 0x0000
R
W
Reset
7
6
5
4
3
2
1
0
IREN
TNP1
TNP0
SBR12
SBR11
SBR10
SBR9
SBR8
0
0
0
0
0
0
0
0
Figure 15-3. SCI Baud Rate Register (SCIBDH)
Module Base + 0x0001
R
W
Reset
7
6
5
4
3
2
1
0
SBR7
SBR6
SBR5
SBR4
SBR3
SBR2
SBR1
SBR0
0
0
0
0
0
1
0
0
Figure 15-4. SCI Baud Rate Register (SCIBDL)
Read: Anytime, if AMAP = 0. If only SCIBDH is written to, a read will not return the correct data until
SCIBDL is written to as well, following a write to SCIBDH.
Write: Anytime, if AMAP = 0.
NOTE
Those two registers are only visible in the memory map if AMAP = 0 (reset
condition).
The SCI baud rate register is used by to determine the baud rate of the SCI, and to control the infrared
modulation/demodulation submodule.
Table 15-2. SCIBDH and SCIBDL Field Descriptions
Field
7
IREN
Description
Infrared Enable Bit — This bit enables/disables the infrared modulation/demodulation submodule.
0 IR disabled
1 IR enabled
6:5
TNP[1:0]
Transmitter Narrow Pulse Bits — These bits enable whether the SCI transmits a 1/16, 3/16, 1/32 or 1/4 narrow
pulse. See Table 15-3.
4:0
7:0
SBR[12:0]
SCI Baud Rate Bits — The baud rate for the SCI is determined by the bits in this register. The baud rate is
calculated two different ways depending on the state of the IREN bit.
The formulas for calculating the baud rate are:
When IREN = 0 then,
SCI baud rate = SCI bus clock / (16 x SBR[12:0])
When IREN = 1 then,
SCI baud rate = SCI bus clock / (32 x SBR[12:1])
Note: The baud rate generator is disabled after reset and not started until the TE bit or the RE bit is set for the
first time. The baud rate generator is disabled when (SBR[12:0] = 0 and IREN = 0) or (SBR[12:1] = 0 and
IREN = 1).
Note: Writing to SCIBDH has no effect without writing to SCIBDL, because writing to SCIBDH puts the data in
a temporary location until SCIBDL is written to.
MC9S12XHZ512 Data Sheet, Rev. 1.06
566
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
Table 15-3. IRSCI Transmit Pulse Width
15.3.2.2
TNP[1:0]
Narrow Pulse Width
11
1/4
10
1/32
01
1/16
00
3/16
SCI Control Register 1 (SCICR1)
Module Base + 0x0002
R
W
Reset
7
6
5
4
3
2
1
0
LOOPS
SCISWAI
RSRC
M
WAKE
ILT
PE
PT
0
0
0
0
0
0
0
0
Figure 15-5. SCI Control Register 1 (SCICR1)
Read: Anytime, if AMAP = 0.
Write: Anytime, if AMAP = 0.
NOTE
This register is only visible in the memory map if AMAP = 0 (reset
condition).
Table 15-4. SCICR1 Field Descriptions
Field
Description
7
LOOPS
Loop Select Bit — LOOPS enables loop operation. In loop operation, the RXD pin is disconnected from the SCI
and the transmitter output is internally connected to the receiver input. Both the transmitter and the receiver must
be enabled to use the loop function.
0 Normal operation enabled
1 Loop operation enabled
The receiver input is determined by the RSRC bit.
6
SCISWAI
5
RSRC
4
M
3
WAKE
SCI Stop in Wait Mode Bit — SCISWAI disables the SCI in wait mode.
0 SCI enabled in wait mode
1 SCI disabled in wait mode
Receiver Source Bit — When LOOPS = 1, the RSRC bit determines the source for the receiver shift register
input. See Table 15-5.
0 Receiver input internally connected to transmitter output
1 Receiver input connected externally to transmitter
Data Format Mode Bit — MODE determines whether data characters are eight or nine bits long.
0 One start bit, eight data bits, one stop bit
1 One start bit, nine data bits, one stop bit
Wakeup Condition Bit — WAKE determines which condition wakes up the SCI: a logic 1 (address mark) in the
most significant bit position of a received data character or an idle condition on the RXD pin.
0 Idle line wakeup
1 Address mark wakeup
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
567
Chapter 15 Serial Communication Interface (S12SCIV5)
Table 15-4. SCICR1 Field Descriptions (continued)
Field
Description
2
ILT
Idle Line Type Bit — ILT determines when the receiver starts counting logic 1s as idle character bits. The
counting begins either after the start bit or after the stop bit. If the count begins after the start bit, then a string of
logic 1s preceding the stop bit may cause false recognition of an idle character. Beginning the count after the
stop bit avoids false idle character recognition, but requires properly synchronized transmissions.
0 Idle character bit count begins after start bit
1 Idle character bit count begins after stop bit
1
PE
Parity Enable Bit — PE enables the parity function. When enabled, the parity function inserts a parity bit in the
most significant bit position.
0 Parity function disabled
1 Parity function enabled
0
PT
Parity Type Bit — PT determines whether the SCI generates and checks for even parity or odd parity. With even
parity, an even number of 1s clears the parity bit and an odd number of 1s sets the parity bit. With odd parity, an
odd number of 1s clears the parity bit and an even number of 1s sets the parity bit.
0 Even parity
1 Odd parity
Table 15-5. Loop Functions
LOOPS
RSRC
Function
0
x
Normal operation
1
0
Loop mode with transmitter output internally connected to receiver input
1
1
Single-wire mode with TXD pin connected to receiver input
MC9S12XHZ512 Data Sheet, Rev. 1.06
568
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.3
SCI Alternative Status Register 1 (SCIASR1)
Module Base + 0x0000
7
R
W
Reset
RXEDGIF
0
6
5
4
3
2
0
0
0
0
BERRV
0
0
0
0
0
1
0
BERRIF
BKDIF
0
0
= Unimplemented or Reserved
Figure 15-6. SCI Alternative Status Register 1 (SCIASR1)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
Table 15-6. SCIASR1 Field Descriptions
Field
7
RXEDGIF
Description
Receive Input Active Edge Interrupt Flag — RXEDGIF is asserted, if an active edge (falling if RXPOL = 0,
rising if RXPOL = 1) on the RXD input occurs. RXEDGIF bit is cleared by writing a “1” to it.
0 No active receive on the receive input has occurred
1 An active edge on the receive input has occurred
2
BERRV
Bit Error Value — BERRV reflects the state of the RXD input when the bit error detect circuitry is enabled and
a mismatch to the expected value happened. The value is only meaningful, if BERRIF = 1.
0 A low input was sampled, when a high was expected
1 A high input reassembled, when a low was expected
1
BERRIF
Bit Error Interrupt Flag — BERRIF is asserted, when the bit error detect circuitry is enabled and if the value
sampled at the RXD input does not match the transmitted value. If the BERRIE interrupt enable bit is set an
interrupt will be generated. The BERRIF bit is cleared by writing a “1” to it.
0 No mismatch detected
1 A mismatch has occurred
0
BKDIF
Break Detect Interrupt Flag — BKDIF is asserted, if the break detect circuitry is enabled and a break signal is
received. If the BKDIE interrupt enable bit is set an interrupt will be generated. The BKDIF bit is cleared by writing
a “1” to it.
0 No break signal was received
1 A break signal was received
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
569
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.4
SCI Alternative Control Register 1 (SCIACR1)
Module Base + 0x0001
7
R
W
Reset
RXEDGIE
0
6
5
4
3
2
0
0
0
0
0
0
0
0
0
0
1
0
BERRIE
BKDIE
0
0
= Unimplemented or Reserved
Figure 15-7. SCI Alternative Control Register 1 (SCIACR1)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
Table 15-7. SCIACR1 Field Descriptions
Field
Description
7
RSEDGIE
Receive Input Active Edge Interrupt Enable — RXEDGIE enables the receive input active edge interrupt flag,
RXEDGIF, to generate interrupt requests.
0 RXEDGIF interrupt requests disabled
1 RXEDGIF interrupt requests enabled
1
BERRIE
0
BKDIE
Bit Error Interrupt Enable — BERRIE enables the bit error interrupt flag, BERRIF, to generate interrupt
requests.
0 BERRIF interrupt requests disabled
1 BERRIF interrupt requests enabled
Break Detect Interrupt Enable — BKDIE enables the break detect interrupt flag, BKDIF, to generate interrupt
requests.
0 BKDIF interrupt requests disabled
1 BKDIF interrupt requests enabled
MC9S12XHZ512 Data Sheet, Rev. 1.06
570
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.5
SCI Alternative Control Register 2 (SCIACR2)
Module Base + 0x0002
R
7
6
5
4
3
0
0
0
0
0
0
0
0
0
W
Reset
0
2
1
0
BERRM1
BERRM0
BKDFE
0
0
0
= Unimplemented or Reserved
Figure 15-8. SCI Alternative Control Register 2 (SCIACR2)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
Table 15-8. SCIACR2 Field Descriptions
Field
Description
2:1
Bit Error Mode — Those two bits determines the functionality of the bit error detect feature. See Table 15-9.
BERRM[1:0]
0
BKDFE
Break Detect Feature Enable — BKDFE enables the break detect circuitry.
0 Break detect circuit disabled
1 Break detect circuit enabled
Table 15-9. Bit Error Mode Coding
BERRM1
BERRM0
Function
0
0
Bit error detect circuit is disabled
0
1
Receive input sampling occurs during the 9th time tick of a transmitted bit
(refer to Figure 15-19)
1
0
Receive input sampling occurs during the 13th time tick of a transmitted bit
(refer to Figure 15-19)
1
1
Reserved
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
571
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.6
SCI Control Register 2 (SCICR2)
Module Base + 0x0003
R
W
Reset
7
6
5
4
3
2
1
0
TIE
TCIE
RIE
ILIE
TE
RE
RWU
SBK
0
0
0
0
0
0
0
0
Figure 15-9. SCI Control Register 2 (SCICR2)
Read: Anytime
Write: Anytime
Table 15-10. SCICR2 Field Descriptions
Field
7
TIE
Description
Transmitter Interrupt Enable Bit — TIE enables the transmit data register empty flag, TDRE, to generate
interrupt requests.
0 TDRE interrupt requests disabled
1 TDRE interrupt requests enabled
6
TCIE
Transmission Complete Interrupt Enable Bit — TCIE enables the transmission complete flag, TC, to generate
interrupt requests.
0 TC interrupt requests disabled
1 TC interrupt requests enabled
5
RIE
Receiver Full Interrupt Enable Bit — RIE enables the receive data register full flag, RDRF, or the overrun flag,
OR, to generate interrupt requests.
0 RDRF and OR interrupt requests disabled
1 RDRF and OR interrupt requests enabled
4
ILIE
Idle Line Interrupt Enable Bit — ILIE enables the idle line flag, IDLE, to generate interrupt requests.
0 IDLE interrupt requests disabled
1 IDLE interrupt requests enabled
3
TE
Transmitter Enable Bit — TE enables the SCI transmitter and configures the TXD pin as being controlled by
the SCI. The TE bit can be used to queue an idle preamble.
0 Transmitter disabled
1 Transmitter enabled
2
RE
Receiver Enable Bit — RE enables the SCI receiver.
0 Receiver disabled
1 Receiver enabled
1
RWU
Receiver Wakeup Bit — Standby state
0 Normal operation.
1 RWU enables the wakeup function and inhibits further receiver interrupt requests. Normally, hardware wakes
the receiver by automatically clearing RWU.
0
SBK
Send Break Bit — Toggling SBK sends one break character (10 or 11 logic 0s, respectively 13 or 14 logics 0s
if BRK13 is set). Toggling implies clearing the SBK bit before the break character has finished transmitting. As
long as SBK is set, the transmitter continues to send complete break characters (10 or 11 bits, respectively 13
or 14 bits).
0 No break characters
1 Transmit break characters
MC9S12XHZ512 Data Sheet, Rev. 1.06
572
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.7
SCI Status Register 1 (SCISR1)
The SCISR1 and SCISR2 registers provides inputs to the MCU for generation of SCI interrupts. Also,
these registers can be polled by the MCU to check the status of these bits. The flag-clearing procedures
require that the status register be read followed by a read or write to the SCI data register.It is permissible
to execute other instructions between the two steps as long as it does not compromise the handling of I/O,
but the order of operations is important for flag clearing.
Module Base + 0x0004
R
7
6
5
4
3
2
1
0
TDRE
TC
RDRF
IDLE
OR
NF
FE
PF
1
0
0
0
0
0
0
W
Reset
1
= Unimplemented or Reserved
Figure 15-10. SCI Status Register 1 (SCISR1)
Read: Anytime
Write: Has no meaning or effect
Table 15-11. SCISR1 Field Descriptions
Field
Description
7
TDRE
Transmit Data Register Empty Flag — TDRE is set when the transmit shift register receives a byte from the
SCI data register. When TDRE is 1, the transmit data register (SCIDRH/L) is empty and can receive a new value
to transmit.Clear TDRE by reading SCI status register 1 (SCISR1), with TDRE set and then writing to SCI data
register low (SCIDRL).
0 No byte transferred to transmit shift register
1 Byte transferred to transmit shift register; transmit data register empty
6
TC
Transmit Complete Flag — TC is set low when there is a transmission in progress or when a preamble or break
character is loaded. TC is set high when the TDRE flag is set and no data, preamble, or break character is being
transmitted.When TC is set, the TXD pin becomes idle (logic 1). Clear TC by reading SCI status register 1
(SCISR1) with TC set and then writing to SCI data register low (SCIDRL). TC is cleared automatically when data,
preamble, or break is queued and ready to be sent. TC is cleared in the event of a simultaneous set and clear of
the TC flag (transmission not complete).
0 Transmission in progress
1 No transmission in progress
5
RDRF
Receive Data Register Full Flag — RDRF is set when the data in the receive shift register transfers to the SCI
data register. Clear RDRF by reading SCI status register 1 (SCISR1) with RDRF set and then reading SCI data
register low (SCIDRL).
0 Data not available in SCI data register
1 Received data available in SCI data register
4
IDLE
Idle Line Flag — IDLE is set when 10 consecutive logic 1s (if M = 0) or 11 consecutive logic 1s (if M =1) appear
on the receiver input. Once the IDLE flag is cleared, a valid frame must again set the RDRF flag before an idle
condition can set the IDLE flag.Clear IDLE by reading SCI status register 1 (SCISR1) with IDLE set and then
reading SCI data register low (SCIDRL).
0 Receiver input is either active now or has never become active since the IDLE flag was last cleared
1 Receiver input has become idle
Note: When the receiver wakeup bit (RWU) is set, an idle line condition does not set the IDLE flag.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
573
Chapter 15 Serial Communication Interface (S12SCIV5)
Table 15-11. SCISR1 Field Descriptions (continued)
Field
Description
3
OR
Overrun Flag — OR is set when software fails to read the SCI data register before the receive shift register
receives the next frame. The OR bit is set immediately after the stop bit has been completely received for the
second frame. The data in the shift register is lost, but the data already in the SCI data registers is not affected.
Clear OR by reading SCI status register 1 (SCISR1) with OR set and then reading SCI data register low
(SCIDRL).
0 No overrun
1 Overrun
Note: OR flag may read back as set when RDRF flag is clear. This may happen if the following sequence of
events occurs:
1. After the first frame is received, read status register SCISR1 (returns RDRF set and OR flag clear);
2. Receive second frame without reading the first frame in the data register (the second frame is not
received and OR flag is set);
3. Read data register SCIDRL (returns first frame and clears RDRF flag in the status register);
4. Read status register SCISR1 (returns RDRF clear and OR set).
Event 3 may be at exactly the same time as event 2 or any time after. When this happens, a dummy
SCIDRL read following event 4 will be required to clear the OR flag if further frames are to be received.
2
NF
Noise Flag — NF is set when the SCI detects noise on the receiver input. NF bit is set during the same cycle as
the RDRF flag but does not get set in the case of an overrun. Clear NF by reading SCI status register 1(SCISR1),
and then reading SCI data register low (SCIDRL).
0 No noise
1 Noise
1
FE
Framing Error Flag — FE is set when a logic 0 is accepted as the stop bit. FE bit is set during the same cycle
as the RDRF flag but does not get set in the case of an overrun. FE inhibits further data reception until it is
cleared. Clear FE by reading SCI status register 1 (SCISR1) with FE set and then reading the SCI data register
low (SCIDRL).
0 No framing error
1 Framing error
0
PF
Parity Error Flag — PF is set when the parity enable bit (PE) is set and the parity of the received data does not
match the parity type bit (PT). PF bit is set during the same cycle as the RDRF flag but does not get set in the
case of an overrun. Clear PF by reading SCI status register 1 (SCISR1), and then reading SCI data register low
(SCIDRL).
0 No parity error
1 Parity error
MC9S12XHZ512 Data Sheet, Rev. 1.06
574
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.8
SCI Status Register 2 (SCISR2)
Module Base + 0x0005
7
R
W
Reset
AMAP
0
6
5
0
0
0
0
4
3
2
1
TXPOL
RXPOL
BRK13
TXDIR
0
0
0
0
0
RAF
0
= Unimplemented or Reserved
Figure 15-11. SCI Status Register 2 (SCISR2)
Read: Anytime
Write: Anytime
Table 15-12. SCISR2 Field Descriptions
Field
Description
7
AMAP
Alternative Map — This bit controls which registers sharing the same address space are accessible. In the reset
condition the SCI behaves as previous versions. Setting AMAP=1 allows the access to another set of control and
status registers and hides the baud rate and SCI control Register 1.
0 The registers labelled SCIBDH (0x0000),SCIBDL (0x0001), SCICR1 (0x0002) are accessible
1 The registers labelled SCIASR1 (0x0000),SCIACR1 (0x0001), SCIACR2 (0x00002) are accessible
4
TXPOL
Transmit Polarity — This bit control the polarity of the transmitted data. In NRZ format, a one is represented by
a mark and a zero is represented by a space for normal polarity, and the opposite for inverted polarity. In IrDA
format, a zero is represented by short high pulse in the middle of a bit time remaining idle low for a one for normal
polarity, and a zero is represented by short low pulse in the middle of a bit time remaining idle high for a one for
inverted polarity.
0 Normal polarity
1 Inverted polarity
3
RXPOL
Receive Polarity — This bit control the polarity of the received data. In NRZ format, a one is represented by a
mark and a zero is represented by a space for normal polarity, and the opposite for inverted polarity. In IrDA
format, a zero is represented by short high pulse in the middle of a bit time remaining idle low for a one for normal
polarity, and a zero is represented by short low pulse in the middle of a bit time remaining idle high for a one for
inverted polarity.
0 Normal polarity
1 Inverted polarity
2
BRK13
Break Transmit Character Length — This bit determines whether the transmit break character is 10 or 11 bit
respectively 13 or 14 bits long. The detection of a framing error is not affected by this bit.
0 Break character is 10 or 11 bit long
1 Break character is 13 or 14 bit long
1
TXDIR
Transmitter Pin Data Direction in Single-Wire Mode — This bit determines whether the TXD pin is going to
be used as an input or output, in the single-wire mode of operation. This bit is only relevant in the single-wire
mode of operation.
0 TXD pin to be used as an input in single-wire mode
1 TXD pin to be used as an output in single-wire mode
0
RAF
Receiver Active Flag — RAF is set when the receiver detects a logic 0 during the RT1 time period of the start
bit search. RAF is cleared when the receiver detects an idle character.
0 No reception in progress
1 Reception in progress
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
575
Chapter 15 Serial Communication Interface (S12SCIV5)
15.3.2.9
SCI Data Registers (SCIDRH, SCIDRL)
Module Base + 0x0006
7
R
6
R8
W
Reset
0
T8
0
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 15-12. SCI Data Registers (SCIDRH)
Module Base + 0x0007
7
6
5
4
3
2
1
0
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
0
0
0
0
0
0
0
0
Reset
Figure 15-13. SCI Data Registers (SCIDRL)
Read: Anytime; reading accesses SCI receive data register
Write: Anytime; writing accesses SCI transmit data register; writing to R8 has no effect
Table 15-13. SCIDRH and SCIDRL Field Descriptions
Field
Description
SCIDRH
7
R8
Received Bit 8 — R8 is the ninth data bit received when the SCI is configured for 9-bit data format (M = 1).
SCIDRH
6
T8
Transmit Bit 8 — T8 is the ninth data bit transmitted when the SCI is configured for 9-bit data format (M = 1).
SCIDRL
7:0
R[7:0]
T[7:0]
R7:R0 — Received bits seven through zero for 9-bit or 8-bit data formats
T7:T0 — Transmit bits seven through zero for 9-bit or 8-bit formats
NOTE
If the value of T8 is the same as in the previous transmission, T8 does not
have to be rewritten.The same value is transmitted until T8 is rewritten
In 8-bit data format, only SCI data register low (SCIDRL) needs to be
accessed.
When transmitting in 9-bit data format and using 8-bit write instructions,
write first to SCI data register high (SCIDRH), then SCIDRL.
MC9S12XHZ512 Data Sheet, Rev. 1.06
576
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4
Functional Description
This section provides a complete functional description of the SCI block, detailing the operation of the
design from the end user perspective in a number of subsections.
Figure 15-14 shows the structure of the SCI module. The SCI allows full duplex, asynchronous, serial
communication between the CPU and remote devices, including other CPUs. The SCI transmitter and
receiver operate independently, although they use the same baud rate generator. The CPU monitors the
status of the SCI, writes the data to be transmitted, and processes received data.
R8
IREN
SCI Data
Register
NF
FE
Ir_RXD
Bus
Clock
Receive
Shift Register
SCRXD
Receive
and Wakeup
Control
PF
RAF
RE
IDLE
RWU
RDRF
LOOPS
OR
RSRC
M
Baud Rate
Generator
IDLE
ILIE
RDRF/OR
Infrared
Receive
Decoder
R16XCLK
RXD
RIE
TIE
WAKE
Data Format
Control
ILT
PE
SBR12:SBR0
TDRE
TDRE
TC
SCI
Interrupt
Request
PT
TC
TCIE
TE
÷16
Transmit
Control
LOOPS
SBK
RSRC
T8
Transmit
Shift Register
RXEDGIE
Active Edge
Detect
RXEDGIF
BKDIF
RXD
SCI Data
Register
Break Detect
BKDFE
SCTXD
BKDIE
LIN Transmit BERRIF
Collision
Detect
BERRIE
R16XCLK
Infrared
Transmit
Encoder
BERRM[1:0]
Ir_TXD
TXD
R32XCLK
TNP[1:0]
IREN
Figure 15-14. Detailed SCI Block Diagram
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
577
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.1
Infrared Interface Submodule
This module provides the capability of transmitting narrow pulses to an IR LED and receiving narrow
pulses and transforming them to serial bits, which are sent to the SCI. The IrDA physical layer
specification defines a half-duplex infrared communication link for exchange data. The full standard
includes data rates up to 16 Mbits/s. This design covers only data rates between 2.4 Kbits/s and 115.2
Kbits/s.
The infrared submodule consists of two major blocks: the transmit encoder and the receive decoder. The
SCI transmits serial bits of data which are encoded by the infrared submodule to transmit a narrow pulse
for every zero bit. No pulse is transmitted for every one bit. When receiving data, the IR pulses should be
detected using an IR photo diode and transformed to CMOS levels by the IR receive decoder (external
from the MCU). The narrow pulses are then stretched by the infrared submodule to get back to a serial bit
stream to be received by the SCI.The polarity of transmitted pulses and expected receive pulses can be
inverted so that a direct connection can be made to external IrDA transceiver modules that uses active low
pulses.
The infrared submodule receives its clock sources from the SCI. One of these two clocks are selected in
the infrared submodule in order to generate either 3/16, 1/16, 1/32 or 1/4 narrow pulses during
transmission. The infrared block receives two clock sources from the SCI, R16XCLK and R32XCLK,
which are configured to generate the narrow pulse width during transmission. The R16XCLK and
R32XCLK are internal clocks with frequencies 16 and 32 times the baud rate respectively. Both
R16XCLK and R32XCLK clocks are used for transmitting data. The receive decoder uses only the
R16XCLK clock.
15.4.1.1
Infrared Transmit Encoder
The infrared transmit encoder converts serial bits of data from transmit shift register to the TXD pin. A
narrow pulse is transmitted for a zero bit and no pulse for a one bit. The narrow pulse is sent in the middle
of the bit with a duration of 1/32, 1/16, 3/16 or 1/4 of a bit time. A narrow high pulse is transmitted for a
zero bit when TXPOL is cleared, while a narrow low pulse is transmitted for a zero bit when TXPOL is set.
15.4.1.2
Infrared Receive Decoder
The infrared receive block converts data from the RXD pin to the receive shift register. A narrow pulse is
expected for each zero received and no pulse is expected for each one received. A narrow high pulse is
expected for a zero bit when RXPOL is cleared, while a narrow low pulse is expected for a zero bit when
RXPOL is set. This receive decoder meets the edge jitter requirement as defined by the IrDA serial infrared
physical layer specification.
15.4.2
LIN Support
This module provides some basic support for the LIN protocol. At first this is a break detect circuitry
making it easier for the LIN software to distinguish a break character from an incoming data stream. As a
further addition is supports a collision detection at the bit level as well as cancelling pending transmissions.
MC9S12XHZ512 Data Sheet, Rev. 1.06
578
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.3
Data Format
The SCI uses the standard NRZ mark/space data format. When Infrared is enabled, the SCI uses RZI data
format where zeroes are represented by light pulses and ones remain low. See Figure 15-15 below.
8-Bit Data Format
(Bit M in SCICR1 Clear)
Start
Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Possible
Parity
Bit
Bit 6
STOP
Bit
Bit 7
Next
Start
Bit
Standard
SCI Data
Infrared
SCI Data
9-Bit Data Format
(Bit M in SCICR1 Set)
Start
Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
POSSIBLE
PARITY
Bit
Bit 6
Bit 7
Bit 8
STOP
Bit
NEXT
START
Bit
Standard
SCI Data
Infrared
SCI Data
Figure 15-15. SCI Data Formats
Each data character is contained in a frame that includes a start bit, eight or nine data bits, and a stop bit.
Clearing the M bit in SCI control register 1 configures the SCI for 8-bit data characters. A frame with eight
data bits has a total of 10 bits. Setting the M bit configures the SCI for nine-bit data characters. A frame
with nine data bits has a total of 11 bits.
Table 15-14. Example of 8-Bit Data Formats
Start
Bit
Data
Bits
Address
Bits
Parity
Bits
Stop
Bit
1
8
0
0
1
1
7
0
1
1
7
1
0
1
1
1
1
The address bit identifies the frame as an address
character. See Section 15.4.6.6, “Receiver Wakeup”.
When the SCI is configured for 9-bit data characters, the ninth data bit is the T8 bit in SCI data register
high (SCIDRH). It remains unchanged after transmission and can be used repeatedly without rewriting it.
A frame with nine data bits has a total of 11 bits.
Table 15-15. Example of 9-Bit Data Formats
Start
Bit
Data
Bits
Address
Bits
Parity
Bits
Stop
Bit
1
9
0
0
1
1
8
0
1
1
8
1
0
1
1
1
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
579
Chapter 15 Serial Communication Interface (S12SCIV5)
1
15.4.4
The address bit identifies the frame as an address
character. See Section 15.4.6.6, “Receiver Wakeup”.
Baud Rate Generation
A 13-bit modulus counter in the baud rate generator derives the baud rate for both the receiver and the
transmitter. The value from 0 to 8191 written to the SBR12:SBR0 bits determines the bus clock divisor.
The SBR bits are in the SCI baud rate registers (SCIBDH and SCIBDL). The baud rate clock is
synchronized with the bus clock and drives the receiver. The baud rate clock divided by 16 drives the
transmitter. The receiver has an acquisition rate of 16 samples per bit time.
Baud rate generation is subject to one source of error:
• Integer division of the bus clock may not give the exact target frequency.
Table 15-16 lists some examples of achieving target baud rates with a bus clock frequency of 25 MHz.
When IREN = 0 then,
SCI baud rate = SCI bus clock / (16 * SCIBR[12:0])
Table 15-16. Baud Rates (Example: Bus Clock = 25 MHz)
Bits
SBR[12:0]
Receiver
Clock (Hz)
Transmitter
Clock (Hz)
Target
Baud Rate
Error
(%)
41
609,756.1
38,109.8
38,400
.76
81
308,642.0
19,290.1
19,200
.47
163
153,374.2
9585.9
9,600
.16
326
76,687.1
4792.9
4,800
.15
651
38,402.5
2400.2
2,400
.01
1302
19,201.2
1200.1
1,200
.01
2604
9600.6
600.0
600
.00
5208
4800.0
300.0
300
.00
MC9S12XHZ512 Data Sheet, Rev. 1.06
580
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.5
Transmitter
Internal Bus
Bus
Clock
÷ 16
Baud Divider
SCI Data Registers
11-Bit Transmit Register
H
8
7
6
5
4
3
2
1
0
TXPOL
SCTXD
L
MSB
M
Start
Stop
SBR12:SBR0
LOOP
CONTROL
TIE
TDRE IRQ
Break (All 0s)
Parity
Generation
Preamble (All 1s)
PT
Shift Enable
PE
Load from SCIDR
T8
To Receiver
LOOPS
RSRC
TDRE
Transmitter Control
TC
TC IRQ
TCIE
TE
BERRIF
BER IRQ
TCIE
SBK
BERRM[1:0]
Transmit
Collision Detect
SCTXD
SCRXD
(From Receiver)
Figure 15-16. Transmitter Block Diagram
15.4.5.1
Transmitter Character Length
The SCI transmitter can accommodate either 8-bit or 9-bit data characters. The state of the M bit in SCI
control register 1 (SCICR1) determines the length of data characters. When transmitting 9-bit data, bit T8
in SCI data register high (SCIDRH) is the ninth bit (bit 8).
15.4.5.2
Character Transmission
To transmit data, the MCU writes the data bits to the SCI data registers (SCIDRH/SCIDRL), which in turn
are transferred to the transmitter shift register. The transmit shift register then shifts a frame out through
the TXD pin, after it has prefaced them with a start bit and appended them with a stop bit. The SCI data
registers (SCIDRH and SCIDRL) are the write-only buffers between the internal data bus and the transmit
shift register.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
581
Chapter 15 Serial Communication Interface (S12SCIV5)
The SCI also sets a flag, the transmit data register empty flag (TDRE), every time it transfers data from the
buffer (SCIDRH/L) to the transmitter shift register.The transmit driver routine may respond to this flag by
writing another byte to the Transmitter buffer (SCIDRH/SCIDRL), while the shift register is still shifting
out the first byte.
To initiate an SCI transmission:
1. Configure the SCI:
a) Select a baud rate. Write this value to the SCI baud registers (SCIBDH/L) to begin the baud
rate generator. Remember that the baud rate generator is disabled when the baud rate is zero.
Writing to the SCIBDH has no effect without also writing to SCIBDL.
b) Write to SCICR1 to configure word length, parity, and other configuration bits
(LOOPS,RSRC,M,WAKE,ILT,PE,PT).
c) Enable the transmitter, interrupts, receive, and wake up as required, by writing to the SCICR2
register bits (TIE,TCIE,RIE,ILIE,TE,RE,RWU,SBK). A preamble or idle character will now
be shifted out of the transmitter shift register.
2. Transmit Procedure for each byte:
a) Poll the TDRE flag by reading the SCISR1 or responding to the TDRE interrupt. Keep in mind
that the TDRE bit resets to one.
b) If the TDRE flag is set, write the data to be transmitted to SCIDRH/L, where the ninth bit is
written to the T8 bit in SCIDRH if the SCI is in 9-bit data format. A new transmission will not
result until the TDRE flag has been cleared.
3. Repeat step 2 for each subsequent transmission.
NOTE
The TDRE flag is set when the shift register is loaded with the next data to
be transmitted from SCIDRH/L, which happens, generally speaking, a little
over half-way through the stop bit of the previous frame. Specifically, this
transfer occurs 9/16ths of a bit time AFTER the start of the stop bit of the
previous frame.
Writing the TE bit from 0 to a 1 automatically loads the transmit shift register with a preamble of 10 logic
1s (if M = 0) or 11 logic 1s (if M = 1). After the preamble shifts out, control logic transfers the data from
the SCI data register into the transmit shift register. A logic 0 start bit automatically goes into the least
significant bit position of the transmit shift register. A logic 1 stop bit goes into the most significant bit
position.
Hardware supports odd or even parity. When parity is enabled, the most significant bit (MSB) of the data
character is the parity bit.
The transmit data register empty flag, TDRE, in SCI status register 1 (SCISR1) becomes set when the SCI
data register transfers a byte to the transmit shift register. The TDRE flag indicates that the SCI data
register can accept new data from the internal data bus. If the transmit interrupt enable bit, TIE, in SCI
control register 2 (SCICR2) is also set, the TDRE flag generates a transmitter interrupt request.
MC9S12XHZ512 Data Sheet, Rev. 1.06
582
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
When the transmit shift register is not transmitting a frame, the TXD pin goes to the idle condition, logic
1. If at any time software clears the TE bit in SCI control register 2 (SCICR2), the transmitter enable signal
goes low and the transmit signal goes idle.
If software clears TE while a transmission is in progress (TC = 0), the frame in the transmit shift register
continues to shift out. To avoid accidentally cutting off the last frame in a message, always wait for TDRE
to go high after the last frame before clearing TE.
To separate messages with preambles with minimum idle line time, use this sequence between messages:
1. Write the last byte of the first message to SCIDRH/L.
2. Wait for the TDRE flag to go high, indicating the transfer of the last frame to the transmit shift
register.
3. Queue a preamble by clearing and then setting the TE bit.
4. Write the first byte of the second message to SCIDRH/L.
15.4.5.3
Break Characters
Writing a logic 1 to the send break bit, SBK, in SCI control register 2 (SCICR2) loads the transmit shift
register with a break character. A break character contains all logic 0s and has no start, stop, or parity bit.
Break character length depends on the M bit in SCI control register 1 (SCICR1). As long as SBK is at logic
1, transmitter logic continuously loads break characters into the transmit shift register. After software
clears the SBK bit, the shift register finishes transmitting the last break character and then transmits at least
one logic 1. The automatic logic 1 at the end of a break character guarantees the recognition of the start bit
of the next frame.
The SCI recognizes a break character when there are 10 or 11(M = 0 or M = 1) consecutive zero received.
Depending if the break detect feature is enabled or not receiving a break character has these effects on SCI
registers.
If the break detect feature is disabled (BKDFE = 0):
• Sets the framing error flag, FE
• Sets the receive data register full flag, RDRF
• Clears the SCI data registers (SCIDRH/L)
• May set the overrun flag, OR, noise flag, NF, parity error flag, PE, or the receiver active flag, RAF
(see 3.4.4 and 3.4.5 SCI Status Register 1 and 2)
If the break detect feature is enabled (BKDFE = 1) there are two scenarios1
The break is detected right from a start bit or is detected during a byte reception.
• Sets the break detect interrupt flag, BKDIF
• Does not change the data register full flag, RDRF or overrun flag OR
• Does not change the framing error flag FE, parity error flag PE.
• Does not clear the SCI data registers (SCIDRH/L)
• May set noise flag NF, or receiver active flag RAF.
1. A Break character in this context are either 10 or 11 consecutive zero received bits
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
583
Chapter 15 Serial Communication Interface (S12SCIV5)
Figure 15-17 shows two cases of break detect. In trace RXD_1 the break symbol starts with the start bit,
while in RXD_2 the break starts in the middle of a transmission. If BRKDFE = 1, in RXD_1 case there
will be no byte transferred to the receive buffer and the RDRF flag will not be modified. Also no framing
error or parity error will be flagged from this transfer. In RXD_2 case, however the break signal starts later
during the transmission. At the expected stop bit position the byte received so far will be transferred to the
receive buffer, the receive data register full flag will be set, a framing error and if enabled and appropriate
a parity error will be set. Once the break is detected the BRKDIF flag will be set.
Start Bit Position
Stop Bit Position
BRKDIF = 1
RXD_1
Zero Bit Counter
1
2
3
4
5
6
7
8
9
10 . . .
BRKDIF = 1
FE = 1
RXD_2
Zero Bit Counter
1
2
3
4
5
6
7
8
9
10
...
Figure 15-17. Break Detection if BRKDFE = 1 (M = 0)
15.4.5.4
Idle Characters
An idle character (or preamble) contains all logic 1s and has no start, stop, or parity bit. Idle character
length depends on the M bit in SCI control register 1 (SCICR1). The preamble is a synchronizing idle
character that begins the first transmission initiated after writing the TE bit from 0 to 1.
If the TE bit is cleared during a transmission, the TXD pin becomes idle after completion of the
transmission in progress. Clearing and then setting the TE bit during a transmission queues an idle
character to be sent after the frame currently being transmitted.
NOTE
When queueing an idle character, return the TE bit to logic 1 before the stop
bit of the current frame shifts out through the TXD pin. Setting TE after the
stop bit appears on TXD causes data previously written to the SCI data
register to be lost. Toggle the TE bit for a queued idle character while the
TDRE flag is set and immediately before writing the next byte to the SCI
data register.
If the TE bit is clear and the transmission is complete, the SCI is not the
master of the TXD pin
MC9S12XHZ512 Data Sheet, Rev. 1.06
584
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.5.5
LIN Transmit Collision Detection
This module allows to check for collisions on the LIN bus.
LIN Physical Interface
Synchronizer Stage
Receive Shift
Register
Compare
RXD Pin
Bit Error
LIN Bus
Bus Clock
Sample
Point
Transmit Shift
Register
TXD Pin
Figure 15-18. Collision Detect Principle
If the bit error circuit is enabled (BERRM[1:0] = 0:1 or = 1:0]), the error detect circuit will compare the
transmitted and the received data stream at a point in time and flag any mismatch. The timing checks run
when transmitter is active (not idle). As soon as a mismatch between the transmitted data and the received
data is detected the following happens:
• The next bit transmitted will have a high level (TXPOL = 0) or low level (TXPOL = 1)
• The transmission is aborted and the byte in transmit buffer is discarded.
• the transmit data register empty and the transmission complete flag will be set
• The bit error interrupt flag, BERRIF, will be set.
• No further transmissions will take place until the BERRIF is cleared.
4
5
6
7
8
BERRM[1:0] = 0:1
9
10
11
12
13
14
15
0
Sampling End
3
Sampling Begin
Input Receive
Shift Register
2
Sampling End
Output Transmit
Shift Register
1
Sampling Begin
0
BERRM[1:0] = 1:1
Compare Sample Points
Figure 15-19. Timing Diagram Bit Error Detection
If the bit error detect feature is disabled, the bit error interrupt flag is cleared.
NOTE
The RXPOL and TXPOL bit should be set the same when transmission
collision detect feature is enabled, otherwise the bit error interrupt flag may
be set incorrectly.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
585
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.6
Receiver
Internal Bus
SBR12:SBR0
RXPOL
Data
Recovery
Loop
Control
H
Start
11-Bit Receive Shift Register
8
7
6
5
4
3
2
1
0
L
All 1s
SCRXD
From TXD Pin
or Transmitter
Stop
Baud Divider
MSB
Bus
Clock
SCI Data Register
RE
RAF
LOOPS
RSRC
FE
M
RWU
NF
WAKE
ILT
PE
PT
Wakeup
Logic
PE
R8
Parity
Checking
Idle IRQ
IDLE
ILIE
BRKDFE
OR
Break
Detect Logic
RIE
BRKDIF
BRKDIE
Active Edge
Detect Logic
RDRF/OR
IRQ
RDRF
Break IRQ
RXEDGIF
RXEDGIE
RX Active Edge IRQ
Figure 15-20. SCI Receiver Block Diagram
15.4.6.1
Receiver Character Length
The SCI receiver can accommodate either 8-bit or 9-bit data characters. The state of the M bit in SCI
control register 1 (SCICR1) determines the length of data characters. When receiving 9-bit data, bit R8 in
SCI data register high (SCIDRH) is the ninth bit (bit 8).
15.4.6.2
Character Reception
During an SCI reception, the receive shift register shifts a frame in from the RXD pin. The SCI data register
is the read-only buffer between the internal data bus and the receive shift register.
After a complete frame shifts into the receive shift register, the data portion of the frame transfers to the
SCI data register. The receive data register full flag, RDRF, in SCI status register 1 (SCISR1) becomes set,
MC9S12XHZ512 Data Sheet, Rev. 1.06
586
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
indicating that the received byte can be read. If the receive interrupt enable bit, RIE, in SCI control
register 2 (SCICR2) is also set, the RDRF flag generates an RDRF interrupt request.
15.4.6.3
Data Sampling
The RT clock rate. The RT clock is an internal signal with a frequency 16 times the baud rate. To adjust
for baud rate mismatch, the RT clock (see Figure 15-21) is re-synchronized:
• After every start bit
• After the receiver detects a data bit change from logic 1 to logic 0 (after the majority of data bit
samples at RT8, RT9, and RT10 returns a valid logic 1 and the majority of the next RT8, RT9, and
RT10 samples returns a valid logic 0)
To locate the start bit, data recovery logic does an asynchronous search for a logic 0 preceded by three logic
1s.When the falling edge of a possible start bit occurs, the RT clock begins to count to 16.
Start Bit
LSB
RXD
Samples
1
1
1
1
1
1
1
1
0
0
Start Bit
Qualification
0
0
Start Bit
Verification
0
0
0
Data
Sampling
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT CLock Count
RT1
RT Clock
Reset RT Clock
Figure 15-21. Receiver Data Sampling
To verify the start bit and to detect noise, data recovery logic takes samples at RT3, RT5, and RT7.
Figure 15-17 summarizes the results of the start bit verification samples.
Table 15-17. Start Bit Verification
RT3, RT5, and RT7 Samples
Start Bit Verification
Noise Flag
000
Yes
0
001
Yes
1
010
Yes
1
011
No
0
100
Yes
1
101
No
0
110
No
0
111
No
0
If start bit verification is not successful, the RT clock is reset and a new search for a start bit begins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
587
Chapter 15 Serial Communication Interface (S12SCIV5)
To determine the value of a data bit and to detect noise, recovery logic takes samples at RT8, RT9, and
RT10. Table 15-18 summarizes the results of the data bit samples.
Table 15-18. Data Bit Recovery
RT8, RT9, and RT10 Samples
Data Bit Determination
Noise Flag
000
0
0
001
0
1
010
0
1
011
1
1
100
0
1
101
1
1
110
1
1
111
1
0
NOTE
The RT8, RT9, and RT10 samples do not affect start bit verification. If any
or all of the RT8, RT9, and RT10 start bit samples are logic 1s following a
successful start bit verification, the noise flag (NF) is set and the receiver
assumes that the bit is a start bit (logic 0).
To verify a stop bit and to detect noise, recovery logic takes samples at RT8, RT9, and RT10. Table 15-19
summarizes the results of the stop bit samples.
Table 15-19. Stop Bit Recovery
RT8, RT9, and RT10 Samples
Framing Error Flag
Noise Flag
000
1
0
001
1
1
010
1
1
011
0
1
100
1
1
101
0
1
110
0
1
111
0
0
MC9S12XHZ512 Data Sheet, Rev. 1.06
588
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
In Figure 15-22 the verification samples RT3 and RT5 determine that the first low detected was noise and
not the beginning of a start bit. The RT clock is reset and the start bit search begins again. The noise flag
is not set because the noise occurred before the start bit was found.
LSB
Start Bit
0
0
0
0
0
0
RT10
1
RT9
RT1
1
RT8
RT1
1
RT7
0
RT1
1
RT1
1
RT5
1
RT1
Samples
RT1
RXD
0
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT2
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-22. Start Bit Search Example 1
In Figure 15-23, verification sample at RT3 is high. The RT3 sample sets the noise flag. Although the
perceived bit time is misaligned, the data samples RT8, RT9, and RT10 are within the bit time and data
recovery is successful.
Perceived Start Bit
Actual Start Bit
LSB
1
0
RT1
RT1
RT1
RT1
1
0
0
0
0
0
RT10
1
RT9
1
RT8
1
RT7
1
RT1
Samples
RT1
RXD
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-23. Start Bit Search Example 2
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
589
Chapter 15 Serial Communication Interface (S12SCIV5)
In Figure 15-24, a large burst of noise is perceived as the beginning of a start bit, although the test sample
at RT5 is high. The RT5 sample sets the noise flag. Although this is a worst-case misalignment of perceived
bit time, the data samples RT8, RT9, and RT10 are within the bit time and data recovery is successful.
Perceived Start Bit
LSB
Actual Start Bit
RT1
RT1
0
1
0
0
0
0
RT10
0
RT9
1
RT8
1
RT7
1
RT1
Samples
RT1
RXD
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-24. Start Bit Search Example 3
Figure 15-25 shows the effect of noise early in the start bit time. Although this noise does not affect proper
synchronization with the start bit time, it does set the noise flag.
Perceived and Actual Start Bit
LSB
RT1
RT1
RT1
RT1
1
1
1
1
0
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
RXD
Samples
1
0
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT9
RT10
RT8
RT7
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-25. Start Bit Search Example 4
MC9S12XHZ512 Data Sheet, Rev. 1.06
590
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
Figure 15-26 shows a burst of noise near the beginning of the start bit that resets the RT clock. The sample
after the reset is low but is not preceded by three high samples that would qualify as a falling edge.
Depending on the timing of the start bit search and on the data, the frame may be missed entirely or it may
set the framing error flag.
Start Bit
0
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
0
1
1
0
0
0
0
0
0
0
0
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT7
1
RT1
Samples
LSB
No Start Bit Found
RXD
RT1
RT1
RT1
RT1
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-26. Start Bit Search Example 5
In Figure 15-27, a noise burst makes the majority of data samples RT8, RT9, and RT10 high. This sets the
noise flag but does not reset the RT clock. In start bits only, the RT8, RT9, and RT10 data samples are
ignored.
Start Bit
LSB
1
1
1
1
1
0
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
0
0
0
1
0
1
RT10
1
RT9
1
RT8
1
RT7
1
RT1
Samples
RT1
RXD
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 15-27. Start Bit Search Example 6
15.4.6.4
Framing Errors
If the data recovery logic does not detect a logic 1 where the stop bit should be in an incoming frame, it
sets the framing error flag, FE, in SCI status register 1 (SCISR1). A break character also sets the FE flag
because a break character has no stop bit. The FE flag is set at the same time that the RDRF flag is set.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
591
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.6.5
Baud Rate Tolerance
A transmitting device may be operating at a baud rate below or above the receiver baud rate. Accumulated
bit time misalignment can cause one of the three stop bit data samples (RT8, RT9, and RT10) to fall outside
the actual stop bit. A noise error will occur if the RT8, RT9, and RT10 samples are not all the same logical
values. A framing error will occur if the receiver clock is misaligned in such a way that the majority of the
RT8, RT9, and RT10 stop bit samples are a logic zero.
As the receiver samples an incoming frame, it re-synchronizes the RT clock on any valid falling edge
within the frame. Re synchronization within frames will correct a misalignment between transmitter bit
times and receiver bit times.
15.4.6.5.1
Slow Data Tolerance
Figure 15-28 shows how much a slow received frame can be misaligned without causing a noise error or
a framing error. The slow stop bit begins at RT8 instead of RT1 but arrives in time for the stop bit data
samples at RT8, RT9, and RT10.
MSB
Stop
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
Receiver
RT Clock
Data
Samples
Figure 15-28. Slow Data
Let’s take RTr as receiver RT clock and RTt as transmitter RT clock.
For an 8-bit data character, it takes the receiver 9 bit times x 16 RTr cycles +7 RTr cycles = 151 RTr cycles
to start data sampling of the stop bit.
With the misaligned character shown in Figure 15-28, the receiver counts 151 RTr cycles at the point when
the count of the transmitting device is 9 bit times x 16 RTt cycles = 144 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a slow 8-bit data
character with no errors is:
((151 – 144) / 151) x 100 = 4.63%
For a 9-bit data character, it takes the receiver 10 bit times x 16 RTr cycles + 7 RTr cycles = 167 RTr cycles
to start data sampling of the stop bit.
With the misaligned character shown in Figure 15-28, the receiver counts 167 RTr cycles at the point when
the count of the transmitting device is 10 bit times x 16 RTt cycles = 160 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a slow 9-bit
character with no errors is:
((167 – 160) / 167) X 100 = 4.19%
MC9S12XHZ512 Data Sheet, Rev. 1.06
592
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.6.5.2
Fast Data Tolerance
Figure 15-29 shows how much a fast received frame can be misaligned. The fast stop bit ends at RT10
instead of RT16 but is still sampled at RT8, RT9, and RT10.
Stop
Idle or Next Frame
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
Receiver
RT Clock
Data
Samples
Figure 15-29. Fast Data
For an 8-bit data character, it takes the receiver 9 bit times x 16 RTr cycles + 10 RTr cycles = 154 RTr cycles
to finish data sampling of the stop bit.
With the misaligned character shown in Figure 15-29, the receiver counts 154 RTr cycles at the point when
the count of the transmitting device is 10 bit times x 16 RTt cycles = 160 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a fast 8-bit
character with no errors is:
((160 – 154) / 160) x 100 = 3.75%
For a 9-bit data character, it takes the receiver 10 bit times x 16 RTr cycles + 10 RTr cycles = 170 RTr cycles
to finish data sampling of the stop bit.
With the misaligned character shown in Figure 15-29, the receiver counts 170 RTr cycles at the point when
the count of the transmitting device is 11 bit times x 16 RTt cycles = 176 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a fast 9-bit
character with no errors is:
((176 – 170) /176) x 100 = 3.40%
15.4.6.6
Receiver Wakeup
To enable the SCI to ignore transmissions intended only for other receivers in multiple-receiver systems,
the receiver can be put into a standby state. Setting the receiver wakeup bit, RWU, in SCI control register 2
(SCICR2) puts the receiver into standby state during which receiver interrupts are disabled.The SCI will
still load the receive data into the SCIDRH/L registers, but it will not set the RDRF flag.
The transmitting device can address messages to selected receivers by including addressing information in
the initial frame or frames of each message.
The WAKE bit in SCI control register 1 (SCICR1) determines how the SCI is brought out of the standby
state to process an incoming message. The WAKE bit enables either idle line wakeup or address mark
wakeup.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
593
Chapter 15 Serial Communication Interface (S12SCIV5)
15.4.6.6.1
Idle Input line Wakeup (WAKE = 0)
In this wakeup method, an idle condition on the RXD pin clears the RWU bit and wakes up the SCI. The
initial frame or frames of every message contain addressing information. All receivers evaluate the
addressing information, and receivers for which the message is addressed process the frames that follow.
Any receiver for which a message is not addressed can set its RWU bit and return to the standby state. The
RWU bit remains set and the receiver remains on standby until another idle character appears on the RXD
pin.
Idle line wakeup requires that messages be separated by at least one idle character and that no message
contains idle characters.
The idle character that wakes a receiver does not set the receiver idle bit, IDLE, or the receive data register
full flag, RDRF.
The idle line type bit, ILT, determines whether the receiver begins counting logic 1s as idle character bits
after the start bit or after the stop bit. ILT is in SCI control register 1 (SCICR1).
15.4.6.6.2
Address Mark Wakeup (WAKE = 1)
In this wakeup method, a logic 1 in the most significant bit (MSB) position of a frame clears the RWU bit
and wakes up the SCI. The logic 1 in the MSB position marks a frame as an address frame that contains
addressing information. All receivers evaluate the addressing information, and the receivers for which the
message is addressed process the frames that follow.Any receiver for which a message is not addressed can
set its RWU bit and return to the standby state. The RWU bit remains set and the receiver remains on
standby until another address frame appears on the RXD pin.
The logic 1 MSB of an address frame clears the receiver’s RWU bit before the stop bit is received and sets
the RDRF flag.
Address mark wakeup allows messages to contain idle characters but requires that the MSB be reserved
for use in address frames.
NOTE
With the WAKE bit clear, setting the RWU bit after the RXD pin has been
idle can cause the receiver to wake up immediately.
15.4.7
Single-Wire Operation
Normally, the SCI uses two pins for transmitting and receiving. In single-wire operation, the RXD pin is
disconnected from the SCI. The SCI uses the TXD pin for both receiving and transmitting.
Transmitter
Receiver
TXD
RXD
Figure 15-30. Single-Wire Operation (LOOPS = 1, RSRC = 1)
MC9S12XHZ512 Data Sheet, Rev. 1.06
594
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
Enable single-wire operation by setting the LOOPS bit and the receiver source bit, RSRC, in SCI control
register 1 (SCICR1). Setting the LOOPS bit disables the path from the RXD pin to the receiver. Setting
the RSRC bit connects the TXD pin to the receiver. Both the transmitter and receiver must be enabled
(TE = 1 and RE = 1).The TXDIR bit (SCISR2[1]) determines whether the TXD pin is going to be used as
an input (TXDIR = 0) or an output (TXDIR = 1) in this mode of operation.
NOTE
In single-wire operation data from the TXD pin is inverted if RXPOL is set.
15.4.8
Loop Operation
In loop operation the transmitter output goes to the receiver input. The RXD pin is disconnected from the
SCI.
Transmitter
TXD
Receiver
RXD
Figure 15-31. Loop Operation (LOOPS = 1, RSRC = 0)
Enable loop operation by setting the LOOPS bit and clearing the RSRC bit in SCI control register 1
(SCICR1). Setting the LOOPS bit disables the path from the RXD pin to the receiver. Clearing the RSRC
bit connects the transmitter output to the receiver input. Both the transmitter and receiver must be enabled
(TE = 1 and RE = 1).
NOTE
In loop operation data from the transmitter is not recognized by the receiver
if RXPOL and TXPOL are not the same.
15.5
Initialization/Application Information
15.5.1
Reset Initialization
See Section 15.3.2, “Register Descriptions”.
15.5.2
15.5.2.1
Modes of Operation
Run Mode
Normal mode of operation.
To initialize a SCI transmission, see Section 15.4.5.2, “Character Transmission”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
595
Chapter 15 Serial Communication Interface (S12SCIV5)
15.5.2.2
Wait Mode
SCI operation in wait mode depends on the state of the SCISWAI bit in the SCI control register 1
(SCICR1).
• If SCISWAI is clear, the SCI operates normally when the CPU is in wait mode.
• If SCISWAI is set, SCI clock generation ceases and the SCI module enters a power-conservation
state when the CPU is in wait mode. Setting SCISWAI does not affect the state of the receiver
enable bit, RE, or the transmitter enable bit, TE.
If SCISWAI is set, any transmission or reception in progress stops at wait mode entry. The
transmission or reception resumes when either an internal or external interrupt brings the CPU out
of wait mode. Exiting wait mode by reset aborts any transmission or reception in progress and
resets the SCI.
15.5.2.3
Stop Mode
The SCI is inactive during stop mode for reduced power consumption. The STOP instruction does not
affect the SCI register states, but the SCI bus clock will be disabled. The SCI operation resumes from
where it left off after an external interrupt brings the CPU out of stop mode. Exiting stop mode by reset
aborts any transmission or reception in progress and resets the SCI.
The receive input active edge detect circuit is still active in stop mode. An active edge on the receive input
can be used to bring the CPU out of stop mode.
15.5.3
Interrupt Operation
This section describes the interrupt originated by the SCI block.The MCU must service the interrupt
requests. Table 15-20 lists the eight interrupt sources of the SCI.
Table 15-20. SCI Interrupt Sources
Interrupt
Source
Local Enable
TDRE
SCISR1[7]
TIE
TC
SCISR1[6]
TCIE
RDRF
SCISR1[5]
RIE
OR
SCISR1[3]
IDLE
SCISR1[4]
RXEDGIF SCIASR1[7]
Description
Active high level. Indicates that a byte was transferred from SCIDRH/L to the
transmit shift register.
Active high level. Indicates that a transmit is complete.
Active high level. The RDRF interrupt indicates that received data is available
in the SCI data register.
Active high level. This interrupt indicates that an overrun condition has occurred.
ILIE
RXEDGIE
Active high level. Indicates that receiver input has become idle.
Active high level. Indicates that an active edge (falling for RXPOL = 0, rising for
RXPOL = 1) was detected.
BERRIF
SCIASR1[1]
BERRIE
Active high level. Indicates that a mismatch between transmitted and received data
in a single wire application has happened.
BKDIF
SCIASR1[0]
BRKDIE
Active high level. Indicates that a break character has been received.
MC9S12XHZ512 Data Sheet, Rev. 1.06
596
Freescale Semiconductor
Chapter 15 Serial Communication Interface (S12SCIV5)
15.5.3.1
Description of Interrupt Operation
The SCI only originates interrupt requests. The following is a description of how the SCI makes a request
and how the MCU should acknowledge that request. The interrupt vector offset and interrupt number are
chip dependent. The SCI only has a single interrupt line (SCI Interrupt Signal, active high operation) and
all the following interrupts, when generated, are ORed together and issued through that port.
15.5.3.1.1
TDRE Description
The TDRE interrupt is set high by the SCI when the transmit shift register receives a byte from the SCI
data register. A TDRE interrupt indicates that the transmit data register (SCIDRH/L) is empty and that a
new byte can be written to the SCIDRH/L for transmission.Clear TDRE by reading SCI status register 1
with TDRE set and then writing to SCI data register low (SCIDRL).
15.5.3.1.2
TC Description
The TC interrupt is set by the SCI when a transmission has been completed. Transmission is completed
when all bits including the stop bit (if transmitted) have been shifted out and no data is queued to be
transmitted. No stop bit is transmitted when sending a break character and the TC flag is set (providing
there is no more data queued for transmission) when the break character has been shifted out. A TC
interrupt indicates that there is no transmission in progress. TC is set high when the TDRE flag is set and
no data, preamble, or break character is being transmitted. When TC is set, the TXD pin becomes idle
(logic 1). Clear TC by reading SCI status register 1 (SCISR1) with TC set and then writing to SCI data
register low (SCIDRL).TC is cleared automatically when data, preamble, or break is queued and ready to
be sent.
15.5.3.1.3
RDRF Description
The RDRF interrupt is set when the data in the receive shift register transfers to the SCI data register. A
RDRF interrupt indicates that the received data has been transferred to the SCI data register and that the
byte can now be read by the MCU. The RDRF interrupt is cleared by reading the SCI status register one
(SCISR1) and then reading SCI data register low (SCIDRL).
15.5.3.1.4
OR Description
The OR interrupt is set when software fails to read the SCI data register before the receive shift register
receives the next frame. The newly acquired data in the shift register will be lost in this case, but the data
already in the SCI data registers is not affected. The OR interrupt is cleared by reading the SCI status
register one (SCISR1) and then reading SCI data register low (SCIDRL).
15.5.3.1.5
IDLE Description
The IDLE interrupt is set when 10 consecutive logic 1s (if M = 0) or 11 consecutive logic 1s (if M = 1)
appear on the receiver input. Once the IDLE is cleared, a valid frame must again set the RDRF flag before
an idle condition can set the IDLE flag. Clear IDLE by reading SCI status register 1 (SCISR1) with IDLE
set and then reading SCI data register low (SCIDRL).
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
597
Chapter 15 Serial Communication Interface (S12SCIV5)
15.5.3.1.6
RXEDGIF Description
The RXEDGIF interrupt is set when an active edge (falling if RXPOL = 0, rising if RXPOL = 1) on the
RXD pin is detected. Clear RXEDGIF by writing a “1” to the SCIASR1 SCI alternative status register 1.
15.5.3.1.7
BERRIF Description
The BERRIF interrupt is set when a mismatch between the transmitted and the received data in a single
wire application like LIN was detected. Clear BERRIF by writing a “1” to the SCIASR1 SCI alternative
status register 1. This flag is also cleared if the bit error detect feature is disabled.
15.5.3.1.8
BKDIF Description
The BKDIF interrupt is set when a break signal was received. Clear BKDIF by writing a “1” to the
SCIASR1 SCI alternative status register 1. This flag is also cleared if break detect feature is disabled.
15.5.4
Recovery from Wait Mode
The SCI interrupt request can be used to bring the CPU out of wait mode.
15.5.5
Recovery from Stop Mode
An active edge on the receive input can be used to bring the CPU out of stop mode.
MC9S12XHZ512 Data Sheet, Rev. 1.06
598
Freescale Semiconductor
Chapter 16
Serial Peripheral Interface (S12SPIV4)
16.1
Introduction
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or the SPI operation can be interrupt driven.
16.1.1
Glossary of Terms
SPI
SS
SCK
MOSI
MISO
MOMI
SISO
16.1.2
Serial Peripheral Interface
Slave Select
Serial Clock
Master Output, Slave Input
Master Input, Slave Output
Master Output, Master Input
Slave Input, Slave Output
Features
The SPI includes these distinctive features:
• Master mode and slave mode
• Bidirectional mode
• Slave select output
• Mode fault error flag with CPU interrupt capability
• Double-buffered data register
• Serial clock with programmable polarity and phase
• Control of SPI operation during wait mode
16.1.3
Modes of Operation
The SPI functions in three modes: run, wait, and stop.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
599
Chapter 16 Serial Peripheral Interface (S12SPIV4)
•
•
•
Run mode
This is the basic mode of operation.
Wait mode
SPI operation in wait mode is a configurable low power mode, controlled by the SPISWAI bit
located in the SPICR2 register. In wait mode, if the SPISWAI bit is clear, the SPI operates like in
run mode. If the SPISWAI bit is set, the SPI goes into a power conservative state, with the SPI clock
generation turned off. If the SPI is configured as a master, any transmission in progress stops, but
is resumed after CPU goes into run mode. If the SPI is configured as a slave, reception and
transmission of a byte continues, so that the slave stays synchronized to the master.
Stop mode
The SPI is inactive in stop mode for reduced power consumption. If the SPI is configured as a
master, any transmission in progress stops, but is resumed after CPU goes into run mode. If the SPI
is configured as a slave, reception and transmission of a byte continues, so that the slave stays
synchronized to the master.
This is a high level description only, detailed descriptions of operating modes are contained in
Section 16.4.7, “Low Power Mode Options”.
16.1.4
Block Diagram
Figure 16-1 gives an overview on the SPI architecture. The main parts of the SPI are status, control and
data registers, shifter logic, baud rate generator, master/slave control logic, and port control logic.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
SPI
2
SPI Control Register 1
BIDIROE
2
SPI Control Register 2
SPC0
SPI Status Register
Slave
Control
SPIF MODF SPTEF
CPOL
CPHA
Phase + SCK In
Slave Baud Rate Polarity
Control
Master Baud Rate
Phase + SCK Out
Polarity
Control
Interrupt Control
SPI
Interrupt
Request
Baud Rate Generator
Master
Control
Counter
Bus Clock
3
SPR
Port
Control
Logic
SCK
SS
Prescaler Clock Select
SPPR
MOSI
Baud Rate
Shift
Clock
Sample
Clock
3
Shifter
SPI Baud Rate Register
Data In
LSBFE=1
LSBFE=0
8
SPI Data Register
8
LSBFE=1
MSB
LSBFE=0
LSBFE=0 LSB
LSBFE=1
Data Out
Figure 16-1. SPI Block Diagram
16.2
External Signal Description
This section lists the name and description of all ports including inputs and outputs that do, or may, connect
off chip. The SPI module has a total of four external pins.
16.2.1
MOSI — Master Out/Slave In Pin
This pin is used to transmit data out of the SPI module when it is configured as a master and receive data
when it is configured as slave.
16.2.2
MISO — Master In/Slave Out Pin
This pin is used to transmit data out of the SPI module when it is configured as a slave and receive data
when it is configured as master.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
601
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.2.3
SS — Slave Select Pin
This pin is used to output the select signal from the SPI module to another peripheral with which a data
transfer is to take place when it is configured as a master and it is used as an input to receive the slave select
signal when the SPI is configured as slave.
16.2.4
SCK — Serial Clock Pin
In master mode, this is the synchronous output clock. In slave mode, this is the synchronous input clock.
16.3
Memory Map and Register Definition
This section provides a detailed description of address space and registers used by the SPI.
16.3.1
Module Memory Map
The memory map for the SPI is given in Figure 16-2. The address listed for each register is the sum of a
base address and an address offset. The base address is defined at the SoC level and the address offset is
defined at the module level. Reads from the reserved bits return zeros and writes to the reserved bits have
no effect.
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
SPIE
SPE
SPTIE
MSTR
CPOL
CPHA
SSOE
LSBFE
0
0
MODFEN
BIDIROE
SPISWAI
SPC0
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
0x0000
SPICR1
R
W
0x0001
SPICR2
R
W
0
0x0002
SPIBR
R
W
0
0x0003
SPISR
R
W
SPIF
0
SPTEF
MODF
0
0
0
0
0x0004
Reserved
R
W
0x0005
SPIDR
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0006
Reserved
R
W
0x0007
Reserved
R
W
0
0
= Unimplemented or Reserved
Figure 16-2. SPI Register Summary
MC9S12XHZ512 Data Sheet, Rev. 1.06
602
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.3.2
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Details of register bit and field function follow the register
diagrams, in bit order.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
603
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.3.2.1
SPI Control Register 1 (SPICR1)
Module Base +0x0000
R
W
Reset
7
6
5
4
3
2
1
0
SPIE
SPE
SPTIE
MSTR
CPOL
CPHA
SSOE
LSBFE
0
0
0
0
0
1
0
0
Figure 16-3. SPI Control Register 1 (SPICR1)
Read: Anytime
Write: Anytime
Table 16-1. SPICR1 Field Descriptions
Field
Description
7
SPIE
SPI Interrupt Enable Bit — This bit enables SPI interrupt requests, if SPIF or MODF status flag is set.
0 SPI interrupts disabled.
1 SPI interrupts enabled.
6
SPE
SPI System Enable Bit — This bit enables the SPI system and dedicates the SPI port pins to SPI system
functions. If SPE is cleared, SPI is disabled and forced into idle state, status bits in SPISR register are reset.
0 SPI disabled (lower power consumption).
1 SPI enabled, port pins are dedicated to SPI functions.
5
SPTIE
SPI Transmit Interrupt Enable — This bit enables SPI interrupt requests, if SPTEF flag is set.
0 SPTEF interrupt disabled.
1 SPTEF interrupt enabled.
4
MSTR
SPI Master/Slave Mode Select Bit — This bit selects whether the SPI operates in master or slave mode.
Switching the SPI from master to slave or vice versa forces the SPI system into idle state.
0 SPI is in slave mode.
1 SPI is in master mode.
3
CPOL
SPI Clock Polarity Bit — This bit selects an inverted or non-inverted SPI clock. To transmit data between SPI
modules, the SPI modules must have identical CPOL values. In master mode, a change of this bit will abort a
transmission in progress and force the SPI system into idle state.
0 Active-high clocks selected. In idle state SCK is low.
1 Active-low clocks selected. In idle state SCK is high.
2
CPHA
SPI Clock Phase Bit — This bit is used to select the SPI clock format. In master mode, a change of this bit will
abort a transmission in progress and force the SPI system into idle state.
0 Sampling of data occurs at odd edges (1,3,5,...,15) of the SCK clock.
1 Sampling of data occurs at even edges (2,4,6,...,16) of the SCK clock.
1
SSOE
Slave Select Output Enable — The SS output feature is enabled only in master mode, if MODFEN is set, by
asserting the SSOE as shown in Table 16-2. In master mode, a change of this bit will abort a transmission in
progress and force the SPI system into idle state.
0
LSBFE
LSB-First Enable — This bit does not affect the position of the MSB and LSB in the data register. Reads and
writes of the data register always have the MSB in bit 7. In master mode, a change of this bit will abort a
transmission in progress and force the SPI system into idle state.
0 Data is transferred most significant bit first.
1 Data is transferred least significant bit first.
MC9S12XHZ512 Data Sheet, Rev. 1.06
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Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Table 16-2. SS Input / Output Selection
16.3.2.2
MODFEN
SSOE
Master Mode
Slave Mode
0
0
SS not used by SPI
SS input
0
1
SS not used by SPI
SS input
1
0
SS input with MODF feature
SS input
1
1
SS is slave select output
SS input
SPI Control Register 2 (SPICR2)
Module Base +0x0001
R
7
6
5
0
0
0
0
0
W
Reset
0
4
3
MODFEN
BIDIROE
0
0
2
0
0
1
0
SPISWAI
SPC0
0
0
= Unimplemented or Reserved
Figure 16-4. SPI Control Register 2 (SPICR2)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 16-3. SPICR2 Field Descriptions
Field
Description
4
MODFEN
Mode Fault Enable Bit — This bit allows the MODF failure to be detected. If the SPI is in master mode and
MODFEN is cleared, then the SS port pin is not used by the SPI. In slave mode, the SS is available only as an
input regardless of the value of MODFEN. For an overview on the impact of the MODFEN bit on the SS port pin
configuration, refer to Table 16-4. In master mode, a change of this bit will abort a transmission in progress and
force the SPI system into idle state.
0 SS port pin is not used by the SPI.
1 SS port pin with MODF feature.
3
BIDIROE
Output Enable in the Bidirectional Mode of Operation — This bit controls the MOSI and MISO output buffer
of the SPI, when in bidirectional mode of operation (SPC0 is set). In master mode, this bit controls the output
buffer of the MOSI port, in slave mode it controls the output buffer of the MISO port. In master mode, with SPC0
set, a change of this bit will abort a transmission in progress and force the SPI into idle state.
0 Output buffer disabled.
1 Output buffer enabled.
1
SPISWAI
SPI Stop in Wait Mode Bit — This bit is used for power conservation while in wait mode.
0 SPI clock operates normally in wait mode.
1 Stop SPI clock generation when in wait mode.
0
SPC0
Serial Pin Control Bit 0 — This bit enables bidirectional pin configurations as shown in Table 16-4. In master
mode, a change of this bit will abort a transmission in progress and force the SPI system into idle state.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
605
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Table 16-4. Bidirectional Pin Configurations
Pin Mode
SPC0
BIDIROE
MISO
MOSI
Master Mode of Operation
Normal
0
X
Master In
Master Out
Bidirectional
1
0
MISO not used by SPI
Master In
1
Master I/O
Slave Mode of Operation
16.3.2.3
Normal
0
X
Slave Out
Slave In
Bidirectional
1
0
Slave In
MOSI not used by SPI
1
Slave I/O
SPI Baud Rate Register (SPIBR)
Module Base +0x0002
7
R
0
W
Reset
0
6
5
4
3
SPPR2
SPPR1
SPPR0
0
0
0
0
0
2
1
0
SPR2
SPR1
SPR0
0
0
0
= Unimplemented or Reserved
Figure 16-5. SPI Baud Rate Register (SPIBR)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 16-5. SPIBR Field Descriptions
Field
Description
6–4
SPPR[2:0]
SPI Baud Rate Preselection Bits — These bits specify the SPI baud rates as shown in Table 16-6. In master
mode, a change of these bits will abort a transmission in progress and force the SPI system into idle state.
2–0
SPR[2:0]
SPI Baud Rate Selection Bits — These bits specify the SPI baud rates as shown in Table 16-6. In master mode,
a change of these bits will abort a transmission in progress and force the SPI system into idle state.
The baud rate divisor equation is as follows:
BaudRateDivisor = (SPPR + 1) • 2(SPR + 1)
Eqn. 16-1
The baud rate can be calculated with the following equation:
Baud Rate = BusClock / BaudRateDivisor
Eqn. 16-2
NOTE
For maximum allowed baud rates, please refer to the SPI Electrical
Specification in the Electricals chapter of this data sheet.
MC9S12XHZ512 Data Sheet, Rev. 1.06
606
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Table 16-6. Example SPI Baud Rate Selection (25 MHz Bus Clock)
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
Baud Rate
Divisor
Baud Rate
0
0
0
0
0
0
2
12.5 Mbit/s
0
0
0
0
0
1
4
6.25 Mbit/s
0
0
0
0
1
0
8
3.125 Mbit/s
0
0
0
0
1
1
16
1.5625 Mbit/s
0
0
0
1
0
0
32
781.25 kbit/s
0
0
0
1
0
1
64
390.63 kbit/s
0
0
0
1
1
0
128
195.31 kbit/s
0
0
0
1
1
1
256
97.66 kbit/s
0
0
1
0
0
0
4
6.25 Mbit/s
0
0
1
0
0
1
8
3.125 Mbit/s
0
0
1
0
1
0
16
1.5625 Mbit/s
0
0
1
0
1
1
32
781.25 kbit/s
0
0
1
1
0
0
64
390.63 kbit/s
0
0
1
1
0
1
128
195.31 kbit/s
0
0
1
1
1
0
256
97.66 kbit/s
0
0
1
1
1
1
512
48.83 kbit/s
0
1
0
0
0
0
6
4.16667 Mbit/s
0
1
0
0
0
1
12
2.08333 Mbit/s
0
1
0
0
1
0
24
1.04167 Mbit/s
0
1
0
0
1
1
48
520.83 kbit/s
0
1
0
1
0
0
96
260.42 kbit/s
0
1
0
1
0
1
192
130.21 kbit/s
0
1
0
1
1
0
384
65.10 kbit/s
0
1
0
1
1
1
768
32.55 kbit/s
0
1
1
0
0
0
8
3.125 Mbit/s
0
1
1
0
0
1
16
1.5625 Mbit/s
0
1
1
0
1
0
32
781.25 kbit/s
0
1
1
0
1
1
64
390.63 kbit/s
0
1
1
1
0
0
128
195.31 kbit/s
0
1
1
1
0
1
256
97.66 kbit/s
0
1
1
1
1
0
512
48.83 kbit/s
0
1
1
1
1
1
1024
24.41 kbit/s
1
0
0
0
0
0
10
2.5 Mbit/s
1
0
0
0
0
1
20
1.25 Mbit/s
1
0
0
0
1
0
40
625 kbit/s
1
0
0
0
1
1
80
312.5 kbit/s
1
0
0
1
0
0
160
156.25 kbit/s
1
0
0
1
0
1
320
78.13 kbit/s
1
0
0
1
1
0
640
39.06 kbit/s
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
607
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Table 16-6. Example SPI Baud Rate Selection (25 MHz Bus Clock) (continued)
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
Baud Rate
Divisor
Baud Rate
1
0
0
1
1
1
1280
19.53 kbit/s
1
0
1
0
0
0
12
2.08333 Mbit/s
1
0
1
0
0
1
24
1.04167 Mbit/s
1
0
1
0
1
0
48
520.83 kbit/s
1
0
1
0
1
1
96
260.42 kbit/s
1
0
1
1
0
0
192
130.21 kbit/s
1
0
1
1
0
1
384
65.10 kbit/s
1
0
1
1
1
0
768
32.55 kbit/s
1
0
1
1
1
1
1536
16.28 kbit/s
1
1
0
0
0
0
14
1.78571 Mbit/s
1
1
0
0
0
1
28
892.86 kbit/s
1
1
0
0
1
0
56
446.43 kbit/s
1
1
0
0
1
1
112
223.21 kbit/s
1
1
0
1
0
0
224
111.61 kbit/s
1
1
0
1
0
1
448
55.80 kbit/s
1
1
0
1
1
0
896
27.90 kbit/s
1
1
0
1
1
1
1792
13.95 kbit/s
1
1
1
0
0
0
16
1.5625 Mbit/s
1
1
1
0
0
1
32
781.25 kbit/s
1
1
1
0
1
0
64
390.63 kbit/s
1
1
1
0
1
1
128
195.31 kbit/s
1
1
1
1
0
0
256
97.66 kbit/s
1
1
1
1
0
1
512
48.83 kbit/s
1
1
1
1
1
0
1024
24.41 kbit/s
1
1
1
1
1
1
2048
12.21 kbit/s
MC9S12XHZ512 Data Sheet, Rev. 1.06
608
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.3.2.4
SPI Status Register (SPISR)
Module Base +0x0003
R
7
6
5
4
3
2
1
0
SPIF
0
SPTEF
MODF
0
0
0
0
0
1
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 16-6. SPI Status Register (SPISR)
Read: Anytime
Write: Has no effect
Table 16-7. SPISR Field Descriptions
Field
Description
7
SPIF
SPIF Interrupt Flag — This bit is set after a received data byte has been transferred into the SPI data register.
This bit is cleared by reading the SPISR register (with SPIF set) followed by a read access to the SPI data
register.
0 Transfer not yet complete.
1 New data copied to SPIDR.
5
SPTEF
SPI Transmit Empty Interrupt Flag — If set, this bit indicates that the transmit data register is empty. To clear
this bit and place data into the transmit data register, SPISR must be read with SPTEF = 1, followed by a write
to SPIDR. Any write to the SPI data register without reading SPTEF = 1, is effectively ignored.
0 SPI data register not empty.
1 SPI data register empty.
4
MODF
Mode Fault Flag — This bit is set if the SS input becomes low while the SPI is configured as a master and mode
fault detection is enabled, MODFEN bit of SPICR2 register is set. Refer to MODFEN bit description in
Section 16.3.2.2, “SPI Control Register 2 (SPICR2)”. The flag is cleared automatically by a read of the SPI status
register (with MODF set) followed by a write to the SPI control register 1.
0 Mode fault has not occurred.
1 Mode fault has occurred.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
609
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.3.2.5
SPI Data Register (SPIDR)
Module Base +0x0005
R
W
Reset
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
2
Bit 0
0
0
0
0
0
0
0
0
Figure 16-7. SPI Data Register (SPIDR)
Read: Anytime; normally read only when SPIF is set
Write: Anytime
The SPI data register is both the input and output register for SPI data. A write to this register
allows a data byte to be queued and transmitted. For an SPI configured as a master, a queued data
byte is transmitted immediately after the previous transmission has completed. The SPI transmitter
empty flag SPTEF in the SPISR register indicates when the SPI data register is ready to accept new
data.
Received data in the SPIDR is valid when SPIF is set.
If SPIF is cleared and a byte has been received, the received byte is transferred from the receive
shift register to the SPIDR and SPIF is set.
If SPIF is set and not serviced, and a second byte has been received, the second received byte is
kept as valid byte in the receive shift register until the start of another transmission. The byte in the
SPIDR does not change.
If SPIF is set and a valid byte is in the receive shift register, and SPIF is serviced before the start of
a third transmission, the byte in the receive shift register is transferred into the SPIDR and SPIF
remains set (see Figure 16-8).
If SPIF is set and a valid byte is in the receive shift register, and SPIF is serviced after the start of
a third transmission, the byte in the receive shift register has become invalid and is not transferred
into the SPIDR (see Figure 16-9).
MC9S12XHZ512 Data Sheet, Rev. 1.06
610
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Data A Received
Data B Received
Data C Received
SPIF Serviced
Receive Shift Register
Data B
Data A
Data C
SPIF
SPI Data Register
Data B
Data A
= Unspecified
Data C
= Reception in progress
Figure 16-8. Reception with SPIF Serviced in Time
Data A Received
Data B Received
Data C Received
Data B Lost
SPIF Serviced
Receive Shift Register
Data B
Data A
Data C
SPIF
SPI Data Register
Data A
= Unspecified
Data C
= Reception in progress
Figure 16-9. Reception with SPIF Serviced too Late
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
611
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4
Functional Description
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or SPI operation can be interrupt driven.
The SPI system is enabled by setting the SPI enable (SPE) bit in SPI control register 1. While SPE is set,
the four associated SPI port pins are dedicated to the SPI function as:
• Slave select (SS)
• Serial clock (SCK)
• Master out/slave in (MOSI)
• Master in/slave out (MISO)
The main element of the SPI system is the SPI data register. The 8-bit data register in the master and the
8-bit data register in the slave are linked by the MOSI and MISO pins to form a distributed 16-bit register.
When a data transfer operation is performed, this 16-bit register is serially shifted eight bit positions by the
S-clock from the master, so data is exchanged between the master and the slave. Data written to the master
SPI data register becomes the output data for the slave, and data read from the master SPI data register after
a transfer operation is the input data from the slave.
A read of SPISR with SPTEF = 1 followed by a write to SPIDR puts data into the transmit data register.
When a transfer is complete and SPIF is cleared, received data is moved into the receive data register. This
8-bit data register acts as the SPI receive data register for reads and as the SPI transmit data register for
writes. A single SPI register address is used for reading data from the read data buffer and for writing data
to the transmit data register.
The clock phase control bit (CPHA) and a clock polarity control bit (CPOL) in the SPI control register 1
(SPICR1) select one of four possible clock formats to be used by the SPI system. The CPOL bit simply
selects a non-inverted or inverted clock. The CPHA bit is used to accommodate two fundamentally
different protocols by sampling data on odd numbered SCK edges or on even numbered SCK edges (see
Section 16.4.3, “Transmission Formats”).
The SPI can be configured to operate as a master or as a slave. When the MSTR bit in SPI control register1
is set, master mode is selected, when the MSTR bit is clear, slave mode is selected.
NOTE
A change of CPOL or MSTR bit while there is a received byte pending in
the receive shift register will destroy the received byte and must be avoided.
MC9S12XHZ512 Data Sheet, Rev. 1.06
612
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.1
Master Mode
The SPI operates in master mode when the MSTR bit is set. Only a master SPI module can initiate
transmissions. A transmission begins by writing to the master SPI data register. If the shift register is
empty, the byte immediately transfers to the shift register. The byte begins shifting out on the MOSI pin
under the control of the serial clock.
• Serial clock
The SPR2, SPR1, and SPR0 baud rate selection bits, in conjunction with the SPPR2, SPPR1, and
SPPR0 baud rate preselection bits in the SPI baud rate register, control the baud rate generator and
determine the speed of the transmission. The SCK pin is the SPI clock output. Through the SCK
pin, the baud rate generator of the master controls the shift register of the slave peripheral.
• MOSI, MISO pin
In master mode, the function of the serial data output pin (MOSI) and the serial data input pin
(MISO) is determined by the SPC0 and BIDIROE control bits.
• SS pin
If MODFEN and SSOE are set, the SS pin is configured as slave select output. The SS output
becomes low during each transmission and is high when the SPI is in idle state.
If MODFEN is set and SSOE is cleared, the SS pin is configured as input for detecting mode fault
error. If the SS input becomes low this indicates a mode fault error where another master tries to
drive the MOSI and SCK lines. In this case, the SPI immediately switches to slave mode, by
clearing the MSTR bit and also disables the slave output buffer MISO (or SISO in bidirectional
mode). So the result is that all outputs are disabled and SCK, MOSI, and MISO are inputs. If a
transmission is in progress when the mode fault occurs, the transmission is aborted and the SPI is
forced into idle state.
This mode fault error also sets the mode fault (MODF) flag in the SPI status register (SPISR). If
the SPI interrupt enable bit (SPIE) is set when the MODF flag becomes set, then an SPI interrupt
sequence is also requested.
When a write to the SPI data register in the master occurs, there is a half SCK-cycle delay. After
the delay, SCK is started within the master. The rest of the transfer operation differs slightly,
depending on the clock format specified by the SPI clock phase bit, CPHA, in SPI control register 1
(see Section 16.4.3, “Transmission Formats”).
NOTE
A change of the bits CPOL, CPHA, SSOE, LSBFE, MODFEN, SPC0, or
BIDIROE with SPC0 set, SPPR2-SPPR0 and SPR2-SPR0 in master mode
will abort a transmission in progress and force the SPI into idle state. The
remote slave cannot detect this, therefore the master must ensure that the
remote slave is returned to idle state.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
613
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.2
Slave Mode
The SPI operates in slave mode when the MSTR bit in SPI control register 1 is clear.
• Serial clock
In slave mode, SCK is the SPI clock input from the master.
• MISO, MOSI pin
In slave mode, the function of the serial data output pin (MISO) and serial data input pin (MOSI)
is determined by the SPC0 bit and BIDIROE bit in SPI control register 2.
• SS pin
The SS pin is the slave select input. Before a data transmission occurs, the SS pin of the slave SPI
must be low. SS must remain low until the transmission is complete. If SS goes high, the SPI is
forced into idle state.
The SS input also controls the serial data output pin, if SS is high (not selected), the serial data
output pin is high impedance, and, if SS is low, the first bit in the SPI data register is driven out of
the serial data output pin. Also, if the slave is not selected (SS is high), then the SCK input is
ignored and no internal shifting of the SPI shift register occurs.
Although the SPI is capable of duplex operation, some SPI peripherals are capable of only
receiving SPI data in a slave mode. For these simpler devices, there is no serial data out pin.
NOTE
When peripherals with duplex capability are used, take care not to
simultaneously enable two receivers whose serial outputs drive the same
system slave’s serial data output line.
As long as no more than one slave device drives the system slave’s serial data output line, it is possible for
several slaves to receive the same transmission from a master, although the master would not receive return
information from all of the receiving slaves.
If the CPHA bit in SPI control register 1 is clear, odd numbered edges on the SCK input cause the data at
the serial data input pin to be latched. Even numbered edges cause the value previously latched from the
serial data input pin to shift into the LSB or MSB of the SPI shift register, depending on the LSBFE bit.
If the CPHA bit is set, even numbered edges on the SCK input cause the data at the serial data input pin to
be latched. Odd numbered edges cause the value previously latched from the serial data input pin to shift
into the LSB or MSB of the SPI shift register, depending on the LSBFE bit.
When CPHA is set, the first edge is used to get the first data bit onto the serial data output pin. When CPHA
is clear and the SS input is low (slave selected), the first bit of the SPI data is driven out of the serial data
output pin. After the eighth shift, the transfer is considered complete and the received data is transferred
into the SPI data register. To indicate transfer is complete, the SPIF flag in the SPI status register is set.
NOTE
A change of the bits CPOL, CPHA, SSOE, LSBFE, MODFEN, SPC0, or
BIDIROE with SPC0 set in slave mode will corrupt a transmission in
progress and must be avoided.
MC9S12XHZ512 Data Sheet, Rev. 1.06
614
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.3
Transmission Formats
During an SPI transmission, data is transmitted (shifted out serially) and received (shifted in serially)
simultaneously. The serial clock (SCK) synchronizes shifting and sampling of the information on the two
serial data lines. A slave select line allows selection of an individual slave SPI device; slave devices that
are not selected do not interfere with SPI bus activities. Optionally, on a master SPI device, the slave select
line can be used to indicate multiple-master bus contention.
MASTER SPI
SHIFT REGISTER
BAUD RATE
GENERATOR
SLAVE SPI
MISO
MISO
MOSI
MOSI
SCK
SCK
SS
VDD
SHIFT REGISTER
SS
Figure 16-10. Master/Slave Transfer Block Diagram
16.4.3.1
Clock Phase and Polarity Controls
Using two bits in the SPI control register 1, software selects one of four combinations of serial clock phase
and polarity.
The CPOL clock polarity control bit specifies an active high or low clock and has no significant effect on
the transmission format.
The CPHA clock phase control bit selects one of two fundamentally different transmission formats.
Clock phase and polarity should be identical for the master SPI device and the communicating slave
device. In some cases, the phase and polarity are changed between transmissions to allow a master device
to communicate with peripheral slaves having different requirements.
16.4.3.2
CPHA = 0 Transfer Format
The first edge on the SCK line is used to clock the first data bit of the slave into the master and the first
data bit of the master into the slave. In some peripherals, the first bit of the slave’s data is available at the
slave’s data out pin as soon as the slave is selected. In this format, the first SCK edge is issued a half cycle
after SS has become low.
A half SCK cycle later, the second edge appears on the SCK line. When this second edge occurs, the value
previously latched from the serial data input pin is shifted into the LSB or MSB of the shift register,
depending on LSBFE bit.
After this second edge, the next bit of the SPI master data is transmitted out of the serial data output pin of
the master to the serial input pin on the slave. This process continues for a total of 16 edges on the SCK
line, with data being latched on odd numbered edges and shifted on even numbered edges.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
615
Chapter 16 Serial Peripheral Interface (S12SPIV4)
Data reception is double buffered. Data is shifted serially into the SPI shift register during the transfer and
is transferred to the parallel SPI data register after the last bit is shifted in.
After the 16th (last) SCK edge:
• Data that was previously in the master SPI data register should now be in the slave data register and
the data that was in the slave data register should be in the master.
• The SPIF flag in the SPI status register is set, indicating that the transfer is complete.
Figure 16-11 is a timing diagram of an SPI transfer where CPHA = 0. SCK waveforms are shown for
CPOL = 0 and CPOL = 1. The diagram may be interpreted as a master or slave timing diagram because
the SCK, MISO, and MOSI pins are connected directly between the master and the slave. The MISO signal
is the output from the slave and the MOSI signal is the output from the master. The SS pin of the master
must be either high or reconfigured as a general-purpose output not affecting the SPI.
End of Idle State
Begin
1
SCK Edge Number
2
3
4
5
6
7
8
Begin of Idle State
End
Transfer
9
10
11
12
13 14
15
16
Bit 1
Bit 6
LSB Minimum 1/2 SCK
for tT, tl, tL
MSB
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
tT
tL
MSB first (LSBFE = 0): MSB
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
LSB first (LSBFE = 1): LSB
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
tL = Minimum leading time before the first SCK edge
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time)
tL, tT, and tI are guaranteed for the master mode and required for the slave mode.
tI
tL
Figure 16-11. SPI Clock Format 0 (CPHA = 0)
MC9S12XHZ512 Data Sheet, Rev. 1.06
616
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
In slave mode, if the SS line is not deasserted between the successive transmissions then the content of the
SPI data register is not transmitted; instead the last received byte is transmitted. If the SS line is deasserted
for at least minimum idle time (half SCK cycle) between successive transmissions, then the content of the
SPI data register is transmitted.
In master mode, with slave select output enabled the SS line is always deasserted and reasserted between
successive transfers for at least minimum idle time.
16.4.3.3
CPHA = 1 Transfer Format
Some peripherals require the first SCK edge before the first data bit becomes available at the data out pin,
the second edge clocks data into the system. In this format, the first SCK edge is issued by setting the
CPHA bit at the beginning of the 8-cycle transfer operation.
The first edge of SCK occurs immediately after the half SCK clock cycle synchronization delay. This first
edge commands the slave to transfer its first data bit to the serial data input pin of the master.
A half SCK cycle later, the second edge appears on the SCK pin. This is the latching edge for both the
master and slave.
When the third edge occurs, the value previously latched from the serial data input pin is shifted into the
LSB or MSB of the SPI shift register, depending on LSBFE bit. After this edge, the next bit of the master
data is coupled out of the serial data output pin of the master to the serial input pin on the slave.
This process continues for a total of 16 edges on the SCK line with data being latched on even numbered
edges and shifting taking place on odd numbered edges.
Data reception is double buffered, data is serially shifted into the SPI shift register during the transfer and
is transferred to the parallel SPI data register after the last bit is shifted in.
After the 16th SCK edge:
• Data that was previously in the SPI data register of the master is now in the data register of the
slave, and data that was in the data register of the slave is in the master.
• The SPIF flag bit in SPISR is set indicating that the transfer is complete.
Figure 16-12 shows two clocking variations for CPHA = 1. The diagram may be interpreted as a master or
slave timing diagram because the SCK, MISO, and MOSI pins are connected directly between the master
and the slave. The MISO signal is the output from the slave, and the MOSI signal is the output from the
master. The SS line is the slave select input to the slave. The SS pin of the master must be either high or
reconfigured as a general-purpose output not affecting the SPI.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
617
Chapter 16 Serial Peripheral Interface (S12SPIV4)
End of Idle State
Begin
SCK Edge Number
1
2
3
4
End
Transfer
5
6
7
8
9
10
11
12
13 14
Begin of Idle State
15
16
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
tT
tL
tI
tL
MSB first (LSBFE = 0):
LSB first (LSBFE = 1):
MSB
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
LSB Minimum 1/2 SCK
for tT, tl, tL
LSB
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
MSB
tL = Minimum leading time before the first SCK edge, not required for back-to-back transfers
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time), not required for back-to-back transfers
Figure 16-12. SPI Clock Format 1 (CPHA = 1)
The SS line can remain active low between successive transfers (can be tied low at all times). This format
is sometimes preferred in systems having a single fixed master and a single slave that drive the MISO data
line.
• Back-to-back transfers in master mode
In master mode, if a transmission has completed and a new data byte is available in the SPI data
register, this byte is sent out immediately without a trailing and minimum idle time.
The SPI interrupt request flag (SPIF) is common to both the master and slave modes. SPIF gets set one
half SCK cycle after the last SCK edge.
MC9S12XHZ512 Data Sheet, Rev. 1.06
618
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.4
SPI Baud Rate Generation
Baud rate generation consists of a series of divider stages. Six bits in the SPI baud rate register (SPPR2,
SPPR1, SPPR0, SPR2, SPR1, and SPR0) determine the divisor to the SPI module clock which results in
the SPI baud rate.
The SPI clock rate is determined by the product of the value in the baud rate preselection bits
(SPPR2–SPPR0) and the value in the baud rate selection bits (SPR2–SPR0). The module clock divisor
equation is shown in Equation 16-3.
BaudRateDivisor = (SPPR + 1) • 2(SPR + 1)
Eqn. 16-3
When all bits are clear (the default condition), the SPI module clock is divided by 2. When the selection
bits (SPR2–SPR0) are 001 and the preselection bits (SPPR2–SPPR0) are 000, the module clock divisor
becomes 4. When the selection bits are 010, the module clock divisor becomes 8, etc.
When the preselection bits are 001, the divisor determined by the selection bits is multiplied by 2. When
the preselection bits are 010, the divisor is multiplied by 3, etc. See Table 16-6 for baud rate calculations
for all bit conditions, based on a 25 MHz bus clock. The two sets of selects allows the clock to be divided
by a non-power of two to achieve other baud rates such as divide by 6, divide by 10, etc.
The baud rate generator is activated only when the SPI is in master mode and a serial transfer is taking
place. In the other cases, the divider is disabled to decrease IDD current.
NOTE
For maximum allowed baud rates, please refer to the SPI Electrical
Specification in the Electricals chapter of this data sheet.
16.4.5
16.4.5.1
Special Features
SS Output
The SS output feature automatically drives the SS pin low during transmission to select external devices
and drives it high during idle to deselect external devices. When SS output is selected, the SS output pin
is connected to the SS input pin of the external device.
The SS output is available only in master mode during normal SPI operation by asserting SSOE and
MODFEN bit as shown in Table 16-2.
The mode fault feature is disabled while SS output is enabled.
NOTE
Care must be taken when using the SS output feature in a multimaster
system because the mode fault feature is not available for detecting system
errors between masters.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
619
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.5.2
Bidirectional Mode (MOMI or SISO)
The bidirectional mode is selected when the SPC0 bit is set in SPI control register 2 (see Table 16-8). In
this mode, the SPI uses only one serial data pin for the interface with external device(s). The MSTR bit
decides which pin to use. The MOSI pin becomes the serial data I/O (MOMI) pin for the master mode, and
the MISO pin becomes serial data I/O (SISO) pin for the slave mode. The MISO pin in master mode and
MOSI pin in slave mode are not used by the SPI.
Table 16-8. Normal Mode and Bidirectional Mode
When SPE = 1
Master Mode MSTR = 1
Serial Out
Normal Mode
SPC0 = 0
MOSI
Serial In
MOSI
SPI
SPI
Serial In
MISO
Serial Out
Bidirectional Mode
SPC0 = 1
Slave Mode MSTR = 0
MOMI
Serial Out
MISO
Serial In
BIDIROE
SPI
Serial In
BIDIROE
SPI
Serial Out
SISO
The direction of each serial I/O pin depends on the BIDIROE bit. If the pin is configured as an output,
serial data from the shift register is driven out on the pin. The same pin is also the serial input to the shift
register.
• The SCK is output for the master mode and input for the slave mode.
• The SS is the input or output for the master mode, and it is always the input for the slave mode.
• The bidirectional mode does not affect SCK and SS functions.
NOTE
In bidirectional master mode, with mode fault enabled, both data pins MISO
and MOSI can be occupied by the SPI, though MOSI is normally used for
transmissions in bidirectional mode and MISO is not used by the SPI. If a
mode fault occurs, the SPI is automatically switched to slave mode. In this
case MISO becomes occupied by the SPI and MOSI is not used. This must
be considered, if the MISO pin is used for another purpose.
MC9S12XHZ512 Data Sheet, Rev. 1.06
620
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.6
Error Conditions
The SPI has one error condition:
• Mode fault error
16.4.6.1
Mode Fault Error
If the SS input becomes low while the SPI is configured as a master, it indicates a system error where more
than one master may be trying to drive the MOSI and SCK lines simultaneously. This condition is not
permitted in normal operation, the MODF bit in the SPI status register is set automatically, provided the
MODFEN bit is set.
In the special case where the SPI is in master mode and MODFEN bit is cleared, the SS pin is not used by
the SPI. In this special case, the mode fault error function is inhibited and MODF remains cleared. In case
the SPI system is configured as a slave, the SS pin is a dedicated input pin. Mode fault error doesn’t occur
in slave mode.
If a mode fault error occurs, the SPI is switched to slave mode, with the exception that the slave output
buffer is disabled. So SCK, MISO, and MOSI pins are forced to be high impedance inputs to avoid any
possibility of conflict with another output driver. A transmission in progress is aborted and the SPI is
forced into idle state.
If the mode fault error occurs in the bidirectional mode for a SPI system configured in master mode, output
enable of the MOMI (MOSI in bidirectional mode) is cleared if it was set. No mode fault error occurs in
the bidirectional mode for SPI system configured in slave mode.
The mode fault flag is cleared automatically by a read of the SPI status register (with MODF set) followed
by a write to SPI control register 1. If the mode fault flag is cleared, the SPI becomes a normal master or
slave again.
NOTE
If a mode fault error occurs and a received data byte is pending in the receive
shift register, this data byte will be lost.
16.4.7
16.4.7.1
Low Power Mode Options
SPI in Run Mode
In run mode with the SPI system enable (SPE) bit in the SPI control register clear, the SPI system is in a
low-power, disabled state. SPI registers remain accessible, but clocks to the core of this module are
disabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
621
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.7.2
SPI in Wait Mode
SPI operation in wait mode depends upon the state of the SPISWAI bit in SPI control register 2.
• If SPISWAI is clear, the SPI operates normally when the CPU is in wait mode
• If SPISWAI is set, SPI clock generation ceases and the SPI module enters a power conservation
state when the CPU is in wait mode.
–
If SPISWAI is set and the SPI is configured for master, any transmission and reception in
progress stops at wait mode entry. The transmission and reception resumes when the SPI exits
wait mode.
–
If SPISWAI is set and the SPI is configured as a slave, any transmission and reception in
progress continues if the SCK continues to be driven from the master. This keeps the slave
synchronized to the master and the SCK.
If the master transmits several bytes while the slave is in wait mode, the slave will continue to
send out bytes consistent with the operation mode at the start of wait mode (i.e., if the slave is
currently sending its SPIDR to the master, it will continue to send the same byte. Else if the
slave is currently sending the last received byte from the master, it will continue to send each
previous master byte).
NOTE
Care must be taken when expecting data from a master while the slave is in
wait or stop mode. Even though the shift register will continue to operate,
the rest of the SPI is shut down (i.e., a SPIF interrupt will not be generated
until exiting stop or wait mode). Also, the byte from the shift register will
not be copied into the SPIDR register until after the slave SPI has exited wait
or stop mode. In slave mode, a received byte pending in the receive shift
register will be lost when entering wait or stop mode. An SPIF flag and
SPIDR copy is generated only if wait mode is entered or exited during a
tranmission. If the slave enters wait mode in idle mode and exits wait mode
in idle mode, neither a SPIF nor a SPIDR copy will occur.
16.4.7.3
SPI in Stop Mode
Stop mode is dependent on the system. The SPI enters stop mode when the module clock is disabled (held
high or low). If the SPI is in master mode and exchanging data when the CPU enters stop mode, the
transmission is frozen until the CPU exits stop mode. After stop, data to and from the external SPI is
exchanged correctly. In slave mode, the SPI will stay synchronized with the master.
The stop mode is not dependent on the SPISWAI bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
622
Freescale Semiconductor
Chapter 16 Serial Peripheral Interface (S12SPIV4)
16.4.7.4
Reset
The reset values of registers and signals are described in Section 16.3, “Memory Map and Register
Definition”, which details the registers and their bit fields.
• If a data transmission occurs in slave mode after reset without a write to SPIDR, it will transmit
garbage, or the byte last received from the master before the reset.
• Reading from the SPIDR after reset will always read a byte of zeros.
16.4.7.5
Interrupts
The SPI only originates interrupt requests when SPI is enabled (SPE bit in SPICR1 set). The following is
a description of how the SPI makes a request and how the MCU should acknowledge that request. The
interrupt vector offset and interrupt priority are chip dependent.
The interrupt flags MODF, SPIF, and SPTEF are logically ORed to generate an interrupt request.
16.4.7.5.1
MODF
MODF occurs when the master detects an error on the SS pin. The master SPI must be configured for the
MODF feature (see Table 16-2). After MODF is set, the current transfer is aborted and the following bit is
changed:
• MSTR = 0, The master bit in SPICR1 resets.
The MODF interrupt is reflected in the status register MODF flag. Clearing the flag will also clear the
interrupt. This interrupt will stay active while the MODF flag is set. MODF has an automatic clearing
process which is described in Section 16.3.2.4, “SPI Status Register (SPISR)”.
16.4.7.5.2
SPIF
SPIF occurs when new data has been received and copied to the SPI data register. After SPIF is set, it does
not clear until it is serviced. SPIF has an automatic clearing process, which is described in
Section 16.3.2.4, “SPI Status Register (SPISR)”.
16.4.7.5.3
SPTEF
SPTEF occurs when the SPI data register is ready to accept new data. After SPTEF is set, it does not clear
until it is serviced. SPTEF has an automatic clearing process, which is described in Section 16.3.2.4, “SPI
Status Register (SPISR)”.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
623
Chapter 16 Serial Peripheral Interface (S12SPIV4)
MC9S12XHZ512 Data Sheet, Rev. 1.06
624
Freescale Semiconductor
Chapter 17
Periodic Interrupt Timer (S12PIT24B4CV1)
17.1
Introduction
The period interrupt timer (PIT) is an array of 24-bit timers that can be used to trigger peripheral modules
or raise periodic interrupts. Refer to Figure 17-1 for a simplified block diagram.
17.1.1
Glossary
Acronyms and Abbreviations
PIT
ISR
CCR
SoC
micro time bases
17.1.2
Periodic Interrupt Timer
Interrupt Service Routine
Condition Code Register
System on Chip
clock periods of the 16-bit timer modulus down-counters, which are generated by the 8-bit
modulus down-counters.
Features
The PIT includes these features:
• Four timers implemented as modulus down-counters with independent time-out periods.
• Time-out periods selectable between 1 and 224 bus clock cycles. Time-out equals m*n bus clock
cycles with 1 <= m <= 256 and 1 <= n <= 65536.
• Timers that can be enabled individually.
• Four time-out interrupts.
• Four time-out trigger output signals available to trigger peripheral modules.
• Start of timer channels can be aligned to each other.
17.1.3
Modes of Operation
Refer to the SoC guide for a detailed explanation of the chip modes.
• Run mode
This is the basic mode of operation.
• Wait mode
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
625
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
PIT operation in wait mode is controlled by the PITSWAI bit located in the PITCFLMT register.
In wait mode, if the bus clock is globally enabled and if the PITSWAI bit is clear, the PIT operates
like in run mode. In wait mode, if the PITSWAI bit is set, the PIT module is stalled.
Stop mode
In full stop mode or pseudo stop mode, the PIT module is stalled.
Freeze mode
PIT operation in freeze mode is controlled by the PITFRZ bit located in the PITCFLMT register.
In freeze mode, if the PITFRZ bit is clear, the PIT operates like in run mode. In freeze mode, if the
PITFRZ bit is set, the PIT module is stalled.
•
•
17.1.4
Block Diagram
Figure 17-1 shows a block diagram of the PIT.
Bus Clock
8-Bit
Micro Timer 0
Micro Time
Base 0
16-Bit Timer 0
16-Bit Timer 1
8-Bit
Micro Timer 1
Micro
Time
Base 1
16-Bit Timer 2
16-Bit Timer 3
Time-Out 0
Time-Out 1
Time-Out 2
Time-Out 3
Interrupt 0
Interface
Trigger 0
Interrupt 1
Interface
Trigger 1
Interrupt 2
Interface
Trigger 2
Interrupt 3
Interface
Trigger 3
Figure 17-1. PIT Block Diagram
17.2
External Signal Description
The PIT module has no external pins.
MC9S12XHZ512 Data Sheet, Rev. 1.06
626
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3
Memory Map and Register Definition
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Details of register bit and field function follow the register
diagrams, in bit order.
Register
Name
0x0000
PITCFLMT
R
W
0x0001
PITFLT
W
0x0002
PITCE
W
Bit 7
6
5
PITE
PITSWAI
PITFRZ
0
0
0
R
3
2
1
Bit 0
0
0
0
0
0
PFLMT1
PFLMT0
0
0
0
0
0
PFLT3
PFLT2
PFLT1
PFLT0
PCE3
PCE2
PCE1
PCE0
PMUX3
PMUX2
PMUX1
PMUX0
PINTE3
PINTE2
PINTE1
PINTE0
PTF3
PTF2
PTF1
PTF0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PMTLD7
PMTLD6
PMTLD5
PMTLD4
PMTLD3
PMTLD2
PMTLD1
PMTLD0
PMTLD7
PMTLD6
PMTLD5
PMTLD4
PMTLD3
PMTLD2
PMTLD1
PMTLD0
PLD15
PLD14
PLD13
PLD12
PLD11
PLD10
PLD9
PLD8
PLD7
PLD6
PLD5
PLD4
PLD3
PLD2
PLD1
PLD0
0x000A
R
PITCNT0 (High) W
PCNT15
PCNT14
PCNT13
PCNT12
PCNT11
PCNT10
PCNT9
PCNT8
0x000B
R
PITCNT0 (Low) W
PCNT7
PCNT6
PCNT5
PCNT4
PCNT3
PCNT2
PCNT1
PCNT0
0x000C
PITLD1 (High)
PLD15
PLD14
PLD13
PLD12
PLD11
PLD10
PLD9
PLD8
0x0003
PITMUX
R
4
R
W
0x0004
PITINTE
W
0x0005
PITTF
W
0x0006
PITMTLD0
R
R
R
W
0x0007
PITMTLD1
W
0x0008
PITLD0 (High)
W
0x0009
PITLD0 (Low)
R
R
R
W
R
W
= Unimplemented or Reserved
Figure 17-2. PIT Register Summary (Sheet 1 of 2)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
627
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
PLD7
PLD6
PLD5
PLD4
PLD3
PLD2
PLD1
PLD0
0x000E
R
PITCNT1 (High) W
PCNT15
PCNT14
PCNT13
PCNT12
PCNT11
PCNT10
PCNT9
PCNT8
0x000F
R
PITCNT1 (Low) W
PCNT7
PCNT6
PCNT5
PCNT4
PCNT3
PCNT2
PCNT1
PCNT0
0x0010
PITLD2 (High)
PLD15
PLD14
PLD13
PLD12
PLD11
PLD10
PLD9
PLD8
PLD7
PLD6
PLD5
PLD4
PLD3
PLD2
PLD1
PLD0
0x0012
R
PITCNT2 (High) W
PCNT15
PCNT14
PCNT13
PCNT12
PCNT11
PCNT10
PCNT9
PCNT8
0x0013
R
PITCNT2 (Low) W
PCNT7
PCNT6
PCNT5
PCNT4
PCNT3
PCNT2
PCNT1
PCNT0
PLD15
PLD14
PLD13
PLD12
PLD11
PLD10
PLD9
PLD8
PLD7
PLD6
PLD5
PLD4
PLD3
PLD2
PLD1
PLD0
0x0016
R
PITCNT3 (High) W
PCNT15
PCNT14
PCNT13
PCNT12
PCNT11
PCNT10
PCNT9
PCNT8
0x0017
R
PITCNT3 (Low) W
PCNT7
PCNT6
PCNT5
PCNT4
PCNT3
PCNT2
PCNT1
PCNT0
0x000D
PITLD1 (Low)
0x0011
PITLD2 (Low)
R
W
R
W
R
W
R
0x0014
PITLD3 (High)
W
0x0015
PITLD3 (Low)
W
R
= Unimplemented or Reserved
Figure 17-2. PIT Register Summary (Sheet 2 of 2)
MC9S12XHZ512 Data Sheet, Rev. 1.06
628
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.1
PIT Control and Force Load Micro Timer Register (PITCFLMT)
Module Base + 0x0000
R
W
Reset
7
6
5
PITE
PITSWAI
PITFRZ
0
0
0
4
3
2
0
0
0
0
0
0
1
0
0
0
PFLMT1
PFLMT0
0
0
= Unimplemented or Reserved
Figure 17-3. PIT Control and Force Load Micro Timer Register (PITCFLMT)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 17-1. PITCFLMT Field Descriptions
Field
Description
7
PITE
PIT Module Enable Bit — This bit enables the PIT module. If PITE is cleared, the PIT module is disabled and
flag bits in the PITTF register are cleared. When PITE is set, individually enabled timers (PCE set) start
down-counting with the corresponding load register values.
0 PIT disabled (lower power consumption).
1 PIT is enabled.
6
PITSWAI
PIT Stop in Wait Mode Bit — This bit is used for power conservation while in wait mode.
0 PIT operates normally in wait mode
1 PIT clock generation stops and freezes the PIT module when in wait mode
5
PITFRZ
PIT Counter Freeze while in Freeze Mode Bit — When during debugging a breakpoint (freeze mode) is
encountered it is useful in many cases to freeze the PIT counters to avoid e.g. interrupt generation. The PITFRZ
bit controls the PIT operation while in freeze mode.
0 PIT operates normally in freeze mode
1 PIT counters are stalled when in freeze mode
1:0
PIT Force Load Bits for Micro Timer 1:0 — These bits have only an effect if the corresponding micro timer is
PFLMT[1:0] active and if the PIT module is enabled (PITE set). Writing a one into a PFLMT bit loads the corresponding 8-bit
micro timer load register into the 8-bit micro timer down-counter. Writing a zero has no effect. Reading these bits
will always return zero.
Note: A micro timer force load affects all timer channels that use the corresponding micro time base.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
629
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.2
PIT Force Load Timer Register (PITFLT)
Module Base + 0x0001
R
7
6
5
4
0
0
0
0
3
W
Reset
0
0
0
2
1
0
0
0
0
0
PFLT3
PFLT2
PFLT1
PFLT0
0
0
0
0
0
= Unimplemented or Reserved
Figure 17-4. PIT Force Load Timer Register (PITFLT)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 17-2. PITFLT Field Descriptions
Field
Description
3:0
PFLT[3:0]
PIT Force Load Bits for Timer 3-0 — These bits have only an effect if the corresponding timer channel (PCE
set) is enabled and if the PIT module is enabled (PITE set). Writing a one into a PFLT bit loads the corresponding
16-bit timer load register into the 16-bit timer down-counter. Writing a zero has no effect. Reading these bits will
always return zero.
17.3.0.3
PIT Channel Enable Register (PITCE)
Module Base + 0x0002
R
7
6
5
4
0
0
0
0
0
0
0
0
W
Reset
3
2
1
0
PCE3
PCE2
PCE1
PCE0
0
0
0
0
= Unimplemented or Reserved
Figure 17-5. PIT Channel Enable Register (PITCE)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 17-3. PITCE Field Descriptions
Field
Description
3:0
PCE[3:0]
PIT Enable Bits for Timer Channel 3:0 — These bits enable the PIT channels 3-0. If PCE is cleared, the PIT
channel is disabled and the corresponding flag bit in the PITTF register is cleared. When PCE is set, and if the
PIT module is enabled (PITE = 1) the 16-bit timer counter is loaded with the start count value and starts
down-counting.
0 The corresponding PIT channel is disabled.
1 The corresponding PIT channel is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
630
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.4
PIT Multiplex Register (PITMUX)
Module Base + 0x0003
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
PMUX3
PMUX2
PMUX1
PMUX0
0
0
0
0
= Unimplemented or Reserved
Figure 17-6. PIT Multiplex Register (PITMUX)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 17-4. PITMUX Field Descriptions
Field
Description
3:0
PMUX[3:0]
PIT Multiplex Bits for Timer Channel 3:0 — These bits select if the corresponding 16-bit timer is connected to
micro time base 1 or 0. If PMUX is modified, the corresponding 16-bit timer is immediately switched to the other
micro time base.
0 The corresponding 16-bit timer counts with micro time base 0.
1 The corresponding 16-bit timer counts with micro time base 1.
17.3.0.5
PIT Interrupt Enable Register (PITINTE)
Module Base + 0x0004
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
PINTE3
PINTE2
PINTE1
PINTE0
0
0
0
0
= Unimplemented or Reserved
Figure 17-7. PIT Interrupt Enable Register (PITINTE)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 17-5. PITINTE Field Descriptions
Field
Description
3:0
PINTE[3:0]
PIT Time-out Interrupt Enable Bits for Timer Channel 3:0 — These bits enable an interrupt service request
whenever the time-out flag PTF of the corresponding PIT channel is set. When an interrupt is pending (PTF set)
enabling the interrupt will immediately cause an interrupt. To avoid this, the corresponding PTF flag has to be
cleared first.
0 Interrupt of the corresponding PIT channel is disabled.
1 Interrupt of the corresponding PIT channel is enabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
631
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.6
PIT Time-Out Flag Register (PITTF)
Module Base + 0x0005
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
PTF3
PTF2
PTF1
PTF0
0
0
0
0
= Unimplemented or Reserved
Figure 17-8. PIT Time-Out Flag Register (PITTF)
Read: Anytime
Write: Anytime (write to clear); writes to the reserved bits have no effect
Table 17-6. PITTF Field Descriptions
Field
Description
3:0
PTF[3:0]
PIT Time-out Flag Bits for Timer Channel 3:0 — PTF is set when the corresponding 16-bit timer modulus
down-counter and the selected 8-bit micro timer modulus down-counter have counted to zero. The flag can be
cleared by writing a one to the flag bit. Writing a zero has no effect. If flag clearing by writing a one and flag setting
happen in the same bus clock cycle, the flag remains set. The flag bits are cleared if the PIT module is disabled
or if the corresponding timer channel is disabled.
0 Time-out of the corresponding PIT channel has not yet occurred.
1 Time-out of the corresponding PIT channel has occurred.
17.3.0.7
PIT Micro Timer Load Register 0 to 1 (PITMTLD0–1)
Module Base + 0x0006
R
W
Reset
7
6
5
4
3
2
1
0
PMTLD7
PMTLD6
PMTLD5
PMTLD4
PMTLD3
PMTLD2
PMTLD1
PMTLD0
0
0
0
0
0
0
0
0
Figure 17-9. PIT Micro Timer Load Register 0 (PITMTLD0)
Module Base + 0x0007
R
W
Reset
7
6
5
4
3
2
1
0
PMTLD7
PMTLD6
PMTLD5
PMTLD4
PMTLD3
PMTLD2
PMTLD1
PMTLD0
0
0
0
0
0
0
0
0
Figure 17-10. PIT Micro Timer Load Register 1 (PITMTLD1)
Read: Anytime
Write: Anytime
MC9S12XHZ512 Data Sheet, Rev. 1.06
632
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
Table 17-7. PITMTLD0–1 Field Descriptions
Field
Description
7:0
PIT Micro Timer Load Bits 7:0 — These bits set the 8-bit modulus down-counter load value of the micro timers.
PMTLD[7:0] Writing a new value into the PITMTLD register will not restart the timer. When the micro timer has counted down
to zero, the PMTLD register value will be loaded. The PFLMT bits in the PITCFLMT register can be used to
immediately update the count register with the new value if an immediate load is desired.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
633
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.8
PIT Load Register 0 to 3 (PITLD0–3)
Module Base + 0x0008, 0x0009
15
R
W
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PLD15 PLD14 PLD13 PLD12 PLD11 PLD10 PLD9 PLD8 PLD7 PLD6 PLD5 PLD4 PLD3 PLD2 PLD1 PLD0
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-11. PIT Load Register 0 (PITLD0)
Module Base + 0x000C, 0x000D
15
R
W
14
13
12
11
10
9
8
7
6
5
PLD15 PLD14 PLD13 PLD12 PLD11 PLD10 PLD9 PLD8 PLD7 PLD6 PLD5 PLD4 PLD3 PLD2 PLD1 PLD0
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-12. PIT Load Register 1 (PITLD1)
Module Base + 0x0010, 0x0011
15
R
W
14
13
12
11
10
9
8
7
6
5
PLD15 PLD14 PLD13 PLD12 PLD11 PLD10 PLD9 PLD8 PLD7 PLD6 PLD5 PLD4 PLD3 PLD2 PLD1 PLD0
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-13. PIT Load Register 2 (PITLD2)
Module Base + 0x0014, 0x0015
15
R
W
14
13
12
11
10
9
8
7
6
5
PLD15 PLD14 PLD13 PLD12 PLD11 PLD10 PLD9 PLD8 PLD7 PLD6 PLD5 PLD4 PLD3 PLD2 PLD1 PLD0
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 17-14. PIT Load Register 3 (PITLD3)
Read: Anytime
Write: Anytime
Table 17-8. PITLD0–3 Field Descriptions
Field
Description
15:0
PLD[15:0]
PIT Load Bits 15:0 — These bits set the 16-bit modulus down-counter load value. Writing a new value into the
PITLD register must be a 16-bit access, to ensure data consistency. It will not restart the timer. When the timer
has counted down to zero the PTF time-out flag will be set and the register value will be loaded. The PFLT bits
in the PITFLT register can be used to immediately update the count register with the new value if an immediate
load is desired.
MC9S12XHZ512 Data Sheet, Rev. 1.06
634
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.3.0.9
PIT Count Register 0 to 3 (PITCNT0–3)
Module Base + 0x000A, 0x000B
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-15. PIT Count Register 0 (PITCNT0)
Module Base + 0x000E, 0x000F
15
14
13
12
11
10
9
8
7
6
5
R PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
W 15
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-16. PIT Count Register 1 (PITCNT1)
Module Base + 0x0012, 0x0013
15
14
13
12
11
10
9
8
7
6
5
R PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
W 15
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
2
1
0
Figure 17-17. PIT Count Register 2 (PITCNT2)
Module Base + 0x0016, 0x0017
15
14
13
12
11
10
9
8
7
6
5
R PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT PCNT
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
W 15
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 17-18. PIT Count Register 3 (PITCNT3)
Read: Anytime
Write: Has no meaning or effect
Table 17-9. PITCNT0–3 Field Descriptions
Field
Description
15:0
PIT Count Bits 15-0 — These bits represent the current 16-bit modulus down-counter value. The read access
PCNT[15:0] for the count register must take place in one clock cycle as a 16-bit access.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
635
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
17.4
Functional Description
Figure 17-19 shows a detailed block diagram of the PIT module. The main parts of the PIT are status,
control and data registers, two 8-bit down-counters, four 16-bit down-counters and an interrupt/trigger
interface.
4
PMUX0
4
PITMUX Register
time-out 0
PFLT1
[1]
8-Bit Micro Timer 0
[0]
Timer 1
PITLD1 Register
PITCNT1 Register
PMUX
Clock
Timer 0
PITLD0 Register
PITCNT0 Register
PITMLD0 Register
Bus
PIT_24B4C
PFLT0
PITFLT Register
timeout 1
[2]
8-Bit Micro Timer 1
[1]
Timer 2
PITLD2 Register
PITCNT2 Register
PITCFLMT Register
4
Hardware
Trigger
PFLT2
PITMLD1 Register
Interrupt /
Trigger Interface
PITTF Register
4
timeout 2
PITINTE Register
Interrupt
Request
PFLT3
PFLMT
PMUX3
Timer 3
PITLD3 Register
PITCNT3 Register
Time-Out 3
Figure 17-19. PIT Detailed Block Diagram
17.4.1
Timer
As shown in Figure 17-1and Figure 17-19, the 24-bit timers are built in a two-stage architecture with four
16-bit modulus down-counters and two 8-bit modulus down-counters. The 16-bit timers are clocked with
two selectable micro time bases which are generated with 8-bit modulus down-counters. Each 16-bit timer
is connected to micro time base 0 or 1 via the PMUX[3:0] bit setting in the PIT Multiplex (PITMUX)
register.
A timer channel is enabled if the module enable bit PITE in the PIT control and force load micro timer
(PITCFLMT) register is set and if the corresponding PCE bit in the PIT channel enable (PITCE) register
is set. Two 8-bit modulus down-counters are used to generate two micro time bases. As soon as a micro
time base is selected for an enabled timer channel, the corresponding micro timer modulus down-counter
will load its start value as specified in the PITMTLD0 or PITMTLD1 register and will start down-counting.
Whenever the micro timer down-counter has counted to zero the PITMTLD register is reloaded and the
connected 16-bit modulus down-counters count one cycle.
MC9S12XHZ512 Data Sheet, Rev. 1.06
636
Freescale Semiconductor
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
Whenever a 16-bit timer counter and the connected 8-bit micro timer counter have counted to zero, the
PITLD register is reloaded and the corresponding time-out flag PTF in the PIT time-out flag (PITTF)
register is set, as shown in Figure 17-20. The time-out period is a function of the timer load (PITLD) and
micro timer load (PITMTLD) registers and the bus clock fBUS:
time-out period = (PITMTLD + 1) * (PITLD + 1) / fBUS.
For example, for a 40 MHz bus clock, the maximum time-out period equals:
256 * 65536 * 25 ns = 419.43 ms.
The current 16-bit modulus down-counter value can be read via the PITCNT register. The micro timer
down-counter values cannot be read.
The 8-bit micro timers can individually be restarted by writing a one to the corresponding force load micro
timer PFLMT bits in the PIT control and force load micro timer (PITCFLMT) register. The 16-bit timers
can individually be restarted by writing a one to the corresponding force load timer PFLT bits in the PIT
forceload timer (PITFLT) register. If desired, any group of timers and micro timers can be restarted at the
same time by using one 16-bit write to the adjacent PITCFLMT and PITFLT registers with the relevant
bits set, as shown in Figure 17-20.
Bus Clock
8-Bit Micro
0
Timer Counter
PITCNT Register
00
2
1
0
2
0001
1
0
2
0000
1
0001
0
2
1
1
2
0000
0
0001
2
1
0000
0
2
1
0
2
0001
8-Bit Force Load
16-Bit Force Load
PTF Flag1
PITTRIG
Time-Out Period
Note 1. The PTF flag clearing depends on the software
Time-Out Period
After Restart
Figure 17-20. PIT Trigger and Flag Signal Timing
17.4.2
Interrupt Interface
Each time-out event can be used to trigger an interrupt service request. For each timer channel, an
individual bit PINTE in the PIT interrupt enable (PITINTE) register exists to enable this feature. If PINTE
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
637
Chapter 17 Periodic Interrupt Timer (S12PIT24B4CV1)
is set, an interrupt service is requested whenever the corresponding time-out flag PTF in the PIT time-out
flag (PITTF) register is set. The flag can be cleared by writing a one to the flag bit.
NOTE
Be careful when resetting the PITE, PINTE or PITCE bits in case of pending
PIT interrupt requests, to avoid spurious interrupt requests.
17.4.3
Hardware Trigger
The PIT module contains four hardware trigger signal lines PITTRIG[3:0], one for each timer channel.
These signals can be connected on SoC level to peripheral modules enabling e.g. periodic ATD conversion
(please refer to the SoC Guide for the mapping of PITTRIG[3:0] signals to peripheral modules).
Whenever a timer channel time-out is reached, the corresponding PTF flag is set and the corresponding
trigger signal PITTRIG triggers a rising edge. The trigger feature requires a minimum time-out period of
two bus clock cycles because the trigger is asserted high for at least one bus clock cycle. For load register
values PITLD = 0x0001 and PITMTLD = 0x0002 the flag setting, trigger timing and a restart with force
load is shown in Figure 17-20.
17.5
17.5.1
Initialization/Application Information
Startup
Set the configuration registers before the PITE bit in the PITCFLMT register is set. Before PITE is set, the
configuration registers can be written in arbitrary order.
17.5.2
Shutdown
When the PITCE register bits, the PITINTE register bits or the PITE bit in the PITCFLMT register are
cleared, the corresponding PIT interrupt flags are cleared. In case of a pending PIT interrupt request, a
spurious interrupt can be generated. Two strategies, which avoid spurious interrupts, are recommended:
1. Reset the PIT interrupt flags only in an ISR. When entering the ISR, the I mask bit in the CCR is
set automatically. The I mask bit must not be cleared before the PIT interrupt flags are cleared.
2. After setting the I mask bit with the SEI instruction, the PIT interrupt flags can be cleared. Then
clear the I mask bit with the CLI instruction to re-enable interrupts.
17.5.3
Flag Clearing
A flag is cleared by writing a one to the flag bit. Always use store or move instructions to write a one in
certain bit positions. Do not use the BSET instructions. Do not use any C-constructs that compile to BSET
instructions. “BSET flag_register, #mask” must not be used for flag clearing because BSET is a
read-modify-write instruction which writes back the “bit-wise or” of the flag_register and the mask into
the flag_register. BSET would clear all flag bits that were set, independent from the mask.
For example, to clear flag bit 0 use: MOVB #$01,PITTF.
MC9S12XHZ512 Data Sheet, Rev. 1.06
638
Freescale Semiconductor
Chapter 18
Pulse-Width Modulator (S12PWM8B8CV1)
18.1
Introduction
The PWM definition is based on the HC12 PWM definitions. It contains the basic features from the HC11
with some of the enhancements incorporated on the HC12: center aligned output mode and four available
clock sources.The PWM module has eight channels with independent control of left and center aligned
outputs on each channel.
Each of the eight channels has a programmable period and duty cycle as well as a dedicated counter. A
flexible clock select scheme allows a total of four different clock sources to be used with the counters. Each
of the modulators can create independent continuous waveforms with software-selectable duty rates from
0% to 100%. The PWM outputs can be programmed as left aligned outputs or center aligned outputs.
18.1.1
Features
The PWM block includes these distinctive features:
• Eight independent PWM channels with programmable period and duty cycle
• Dedicated counter for each PWM channel
• Programmable PWM enable/disable for each channel
• Software selection of PWM duty pulse polarity for each channel
• Period and duty cycle are double buffered. Change takes effect when the end of the effective period
is reached (PWM counter reaches zero) or when the channel is disabled.
• Programmable center or left aligned outputs on individual channels
• Eight 8-bit channel or four 16-bit channel PWM resolution
• Four clock sources (A, B, SA, and SB) provide for a wide range of frequencies
• Programmable clock select logic
• Emergency shutdown
18.1.2
Modes of Operation
There is a software programmable option for low power consumption in wait mode that disables the input
clock to the prescaler.
In freeze mode there is a software programmable option to disable the input clock to the prescaler. This is
useful for emulation.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
639
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
18.1.3
Block Diagram
Figure 18-1 shows the block diagram for the 8-bit 8-channel PWM block.
PWM8B8C
PWM Channels
Channel 7
Period and Duty
Counter
Channel 6
Bus Clock
Clock Select
PWM Clock
Period and Duty
PWM6
Counter
Channel 5
Period and Duty
PWM7
PWM5
Counter
Control
Channel 4
Period and Duty
PWM4
Counter
Channel 3
Enable
Period and Duty
PWM3
Counter
Channel 2
Polarity
Period and Duty
Alignment
PWM2
Counter
Channel 1
Period and Duty
PWM1
Counter
Channel 0
Period and Duty
Counter
PWM0
Figure 18-1. PWM Block Diagram
18.2
External Signal Description
The PWM module has a total of 8 external pins.
18.2.1
PWM7 — PWM Channel 7
This pin serves as waveform output of PWM channel 7 and as an input for the emergency shutdown
feature.
18.2.2
PWM6 — PWM Channel 6
This pin serves as waveform output of PWM channel 6.
MC9S12XHZ512 Data Sheet, Rev. 1.06
640
Freescale Semiconductor
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
18.2.3
PWM5 — PWM Channel 5
This pin serves as waveform output of PWM channel 5.
18.2.4
PWM4 — PWM Channel 4
This pin serves as waveform output of PWM channel 4.
18.2.5
PWM3 — PWM Channel 3
This pin serves as waveform output of PWM channel 3.
18.2.6
PWM3 — PWM Channel 2
This pin serves as waveform output of PWM channel 2.
18.2.7
PWM3 — PWM Channel 1
This pin serves as waveform output of PWM channel 1.
18.2.8
PWM3 — PWM Channel 0
This pin serves as waveform output of PWM channel 0.
18.3
Memory Map and Register Definition
This section describes in detail all the registers and register bits in the PWM module.
The special-purpose registers and register bit functions that are not normally available to device end users,
such as factory test control registers and reserved registers, are clearly identified by means of shading the
appropriate portions of address maps and register diagrams. Notes explaining the reasons for restricting
access to the registers and functions are also explained in the individual register descriptions.
18.3.1
Module Memory Map
This section describes the content of the registers in the PWM module. The base address of the PWM
module is determined at the MCU level when the MCU is defined. The register decode map is fixed and
begins at the first address of the module address offset. The figure below shows the registers associated
with the PWM and their relative offset from the base address. The register detail description follows the
order they appear in the register map.
Reserved bits within a register will always read as 0 and the write will be unimplemented. Unimplemented
functions are indicated by shading the bit. .
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
641
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
NOTE
Register Address = Base Address + Address Offset, where the Base Address
is defined at the MCU level and the Address Offset is defined at the module
level.
18.3.2
Register Descriptions
This section describes in detail all the registers and register bits in the PWM module.
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
PWME7
PWME6
PWME5
PWME4
PWME3
PWME2
PWME1
PWME0
PPOL7
PPOL6
PPOL5
PPOL4
PPOL3
PPOL2
PPOL1
PPOL0
PCLK7
PCLKL6
PCLK5
PCLK4
PCLK3
PCLK2
PCLK1
PCLK0
PCKB2
PCKB1
PCKB0
PCKA2
PCKA1
PCKA0
CAE7
CAE6
CAE5
CAE4
CAE3
CAE2
CAE1
CAE0
CON67
CON45
CON23
CON01
PSWAI
PFRZ
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0x0008
R
PWMSCLA W
Bit 7
6
5
4
3
2
1
Bit 0
0x0009
R
PWMSCLB W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0000
PWME
R
W
0x0001
PWMPOL
R
W
0x0002
PWMCLK
W
R
0x0003
R
PWMPRCLK W
0x0004
PWMCAE
W
0x0005
PWMCTL
W
0x0006
PWMTST1
R
R
R
0
0
W
0x0007
R
PWMPRSC1 W
0x000A
R
PWMSCNTA W
1
= Unimplemented or Reserved
Figure 18-2. PWM Register Summary (Sheet 1 of 3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
642
Freescale Semiconductor
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x000B
R
PWMSCNTB W
1
0
0
0
0
0
0
0
0
0x000C
R
PWMCNT0 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x000D
R
PWMCNT1 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x000E
R
PWMCNT2 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x000F
R
PWMCNT3 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0010
R
PWMCNT4 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0011
R
PWMCNT5 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0012
R
PWMCNT6 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0013
R
PWMCNT7 W
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0x0014
R
PWMPER0 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0015
R
PWMPER1 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0016
R
PWMPER2 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0017
R
PWMPER3 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0018
R
PWMPER4 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0019
R
PWMPER5 W
Bit 7
6
5
4
3
2
1
Bit 0
= Unimplemented or Reserved
Figure 18-2. PWM Register Summary (Sheet 2 of 3)
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
643
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x001A
R
PWMPER6 W
Bit 7
6
5
4
3
2
1
Bit 0
0x001B
R
PWMPER7 W
Bit 7
6
5
4
3
2
1
Bit 0
0x001C
R
PWMDTY0 W
Bit 7
6
5
4
3
2
1
Bit 0
0x001D
R
PWMDTY1 W
Bit 7
6
5
4
3
2
1
Bit 0
0x001E
R
PWMDTY2 W
Bit 7
6
5
4
3
2
1
Bit 0
0x001F
R
PWMDTY3 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0010
R
PWMDTY4 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0021
R
PWMDTY5 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0022
R
PWMDTY6 W
Bit 7
6
5
4
3
2
1
Bit 0
0x0023
R
PWMDTY7 W
Bit 7
6
5
4
3
2
1
Bit 0
PWMIF
PWMIE
0
PWM7IN
PWM7INL
PWM7ENA
0x0024
PWMSDN
R
W
0
PWMRSTRT
PWMLVL
= Unimplemented or Reserved
Figure 18-2. PWM Register Summary (Sheet 3 of 3)
1
Intended for factory test purposes only.
18.3.2.1
PWM Enable Register (PWME)
Each PWM channel has an enable bit (PWMEx) to start its waveform output. When any of the PWMEx
bits are set (PWMEx = 1), the associated PWM output is enabled immediately. However, the actual PWM
waveform is not available on the associated PWM output until its clock source begins its next cycle due to
the synchronization of PWMEx and the clock source.
NOTE
The first PWM cycle after enabling the channel can be irregular.
MC9S12XHZ512 Data Sheet, Rev. 1.06
644
Freescale Semiconductor
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
An exception to this is when channels are concatenated. Once concatenated mode is enabled (CONxx bits
set in PWMCTL register), enabling/disabling the corresponding 16-bit PWM channel is controlled by the
low order PWMEx bit.In this case, the high order bytes PWMEx bits have no effect and their
corresponding PWM output lines are disabled.
While in run mode, if all eight PWM channels are disabled (PWME7–0 = 0), the prescaler counter shuts
off for power savings.
Module Base + 0x0000
R
W
Reset
7
6
5
4
3
2
1
0
PWME7
PWME6
PWME5
PWME4
PWME3
PWME2
PWME1
PWME0
0
0
0
0
0
0
0
0
Figure 18-3. PWM Enable Register (PWME)
Read: Anytime
Write: Anytime
Table 18-1. PWME Field Descriptions
Field
Description
7
PWME7
Pulse Width Channel 7 Enable
0 Pulse width channel 7 is disabled.
1 Pulse width channel 7 is enabled. The pulse modulated signal becomes available at PWM output bit 7 when
its clock source begins its next cycle.
6
PWME6
Pulse Width Channel 6 Enable
0 Pulse width channel 6 is disabled.
1 Pulse width channel 6 is enabled. The pulse modulated signal becomes available at PWM output bit6 when
its clock source begins its next cycle. If CON67=1, then bit has no effect and PWM output line 6 is disabled.
5
PWME5
Pulse Width Channel 5 Enable
0 Pulse width channel 5 is disabled.
1 Pulse width channel 5 is enabled. The pulse modulated signal becomes available at PWM output bit 5 when
its clock source begins its next cycle.
4
PWME4
Pulse Width Channel 4 Enable
0 Pulse width channel 4 is disabled.
1 Pulse width channel 4 is enabled. The pulse modulated signal becomes available at PWM, output bit 4 when
its clock source begins its next cycle. If CON45 = 1, then bit has no effect and PWM output bit4 is disabled.
3
PWME3
Pulse Width Channel 3 Enable
0 Pulse width channel 3 is disabled.
1 Pulse width channel 3 is enabled. The pulse modulated signal becomes available at PWM, output bit 3 when
its clock source begins its next cycle.
2
PWME2
Pulse Width Channel 2 Enable
0 Pulse width channel 2 is disabled.
1 Pulse width channel 2 is enabled. The pulse modulated signal becomes available at PWM, output bit 2 when
its clock source begins its next cycle. If CON23 = 1, then bit has no effect and PWM output bit2 is disabled.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
645
Chapter 18 Pulse-Width Modulator (S12PWM8B8CV1)
Table 18-1. PWME Field Descriptions (continued)
Field
Description
1
PWME1
Pulse Width Channel 1 Enable
0 Pulse width channel 1 is disabled.
1 Pulse width channel 1 is enabled. The pulse modulated signal becomes available at PWM, output bit 1 when
its clock source begins its next cycle.
0
PWME0
Pulse Width Channel 0 Enable
0 Pulse width channel 0 is disabled.
1 Pulse width channel 0 is enabled. The pulse modulated signal becomes available at PWM, output bit 0 when
its clock source begins its next cycle. If CON01 = 1, then bit has no effect and PWM output line0 is disabled.
18.3.2.2
PWM Polarity Register (PWMPOL)
The starting polarity of each PWM channel waveform is determined by the associated PPOLx bit in the
PWMPOL register. If the polarity bit is one, the PWM channel output is high at the beginning of the cycle
and then goes low when the duty count is reached. Conversely, if the polarity bit is zero, the output starts
low and then goes high when the duty count is reached.
Module Base + 0x0001
R
W
Reset
7
6
5
4
3
2
1
0
PPOL7
PPOL6
PPOL5
PPOL4
PPOL3
PPOL2
PPOL1
PPOL0
0
0
0
0
0
0
0
0
Figure 18-4. PWM Polarity Register (PWMPOL)
Read: Anytime
Write: Anytime
NOTE
PPOLx register bits can be written anytime. If the polarity is changed while
a PWM signal is being generated, a truncated or stretched pulse can occ