Freescale MC68HC11A0FU1 Rom-based high-performance microcontroller Datasheet

Freescale Semiconductor, Inc.
HC11
Freescale Semiconductor, Inc...
MC68HC11D3
Technical Data
For More Information On This Product,
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Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
Freescale Semiconductor, Inc.
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TABLE OF CONTENTS
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Number
Section 1
INTRODUCTION
1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2 Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Freescale Semiconductor, Inc...
Section 2
PIN DESCRIPTIONS
2.1 VDD, VSS, and EVSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Reset (RESET) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Crystal Driver and External Clock Input (XTAL, EXTAL) . . . . . . . . . . . . . . . . . . . .
2.4 E-Clock Output (E) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 Interrupt Request (IRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.6 Non-Maskable Interrupt (XIRQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 MODA and MODB (MODA/LIR,and MODB/VSTBY) . . . . . . . . . . . . . . . . . . . . . . . .
2.8 PD6/AS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9 PD7/R/W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10 Port Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10.1 Port A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10.2 Port B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10.3 Port C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10.4 Port D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2
2-2
2-3
2-4
2-4
2-4
2-5
2-5
2-5
2-6
2-7
2-7
2-7
2-8
Section 3
CENTRAL PROCESSING UNIT
3.1 CPU Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.1 Accumulators A, B, and D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.2 Index Register X (IX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.3 Index Register Y (IY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.4 Stack Pointer (SP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.5 Program Counter (PC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6 Condition Code Register (CCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.1 Carry/Borrow (C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.2 Overflow (V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.3 Zero (Z). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.4 Negative (N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.5 Interrupt Mask (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.6 Half Carry (H) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.7 X Interrupt Mask (X) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.6.8 Stop Disable (S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Data Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Opcodes and Operands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.1 Immediate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2 Direct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2.1 Extended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2.2 Indexed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2.3 Inherent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2.4 Relative. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5 Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TECHNICAL DATA
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3-1
3-2
3-2
3-2
3-2
3-4
3-4
3-4
3-5
3-5
3-5
3-5
3-5
3-5
3-6
3-6
3-6
3-6
3-7
3-7
3-7
3-7
3-7
3-7
3-8
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Section 4
OPERATING MODES AND ON-CHIP MEMORY
4.1 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.1 Single-Chip Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.2 Expanded Multiplexed Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1.3 Special Test Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.1.4 Bootstrap Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.2 Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
4.2.1 Priority and Mode Select Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
4.2.2 System Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
4.2.2.1 CONFIG Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
4.2.2.2 INIT Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
4.2.2.3 OPTION Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Freescale Semiconductor, Inc...
Section 5
RESETS AND INTERRUPTS
5.1 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.1 Power-On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.2 External Reset (RESET). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.3 COP Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.4 Clock Monitor Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
5.1.5 Option Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
5.1.6 CONFIG Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.2 Effects of Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.2.1 CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.2.2 Memory Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.2.3 Parallel I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5.2.4 Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5.2.5 Real-Time Interrupt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5.2.6 Pulse Accumulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
5.2.7 COP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.2.8 SCI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.2.9 SPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.2.10 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.3 Reset and Interrupt Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.3.1 Highest Priority Interrupt and Miscellaneous Register . . . . . . . . . . . . . . . . . 5-7
5.4 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
5.4.1 Interrupt Recognition and Register Stacking . . . . . . . . . . . . . . . . . . . . . . . . 5-9
5.4.2 Non-Maskable Interrupt Request XIRQ . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
5.4.3 Illegal Opcode Trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
5.4.4 Software Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
5.4.5 Maskable Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
5.4.6 Reset and Interrupt Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
5.5 Low-Power Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
5.5.1 WAIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
5.5.2 STOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
Section 6
PARALLEL I/O
6.1 Port A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.2 Port B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.3 Port C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
iv
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6.4 Port D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.5 Parallel I/O Control Register (PIOC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Section 7
SERIAL COMMUNICATIONS INTERFACE
Freescale Semiconductor, Inc...
7.1
7.2
7.3
7.4
Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Transmit Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Receive Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Wake-up Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
7.4.1 Idle-Line Wakeup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
7.4.2 Address-Mark Wakeup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
7.5 SCI Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
7.6 SCI Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
7.6.1 Serial Communications Data Register (SCDR) . . . . . . . . . . . . . . . . . . . . . . 7-5
7.6.2 Serial Communications Control Register 1 (SCCR1) . . . . . . . . . . . . . . . . . . 7-5
7.6.3 Serial Communications Control Register 2 (SCCR2) . . . . . . . . . . . . . . . . . . 7-6
7.6.4 Serial Communication Status Register (SCSR) . . . . . . . . . . . . . . . . . . . . . . 7-7
7.6.5 Baud Rate Register (BAUD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
7.7 Status Flags and Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Section 8
SERIAL PERIPHERAL INTERFACE
8.1 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2 SPI Transfer Formats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2.1 Clock Phase and Polarity Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3 SPI Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3.1 Master In Slave Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3.2 Master Out Slave In . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3.3 Serial Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3.4 Slave Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.4 SPI System Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5 SPI Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5.1 Serial Peripheral Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5.2 Serial Peripheral Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5.3 Serial Peripheral Data I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-1
8-2
8-3
8-3
8-4
8-4
8-4
8-4
8-4
8-5
8-6
8-7
8-7
Section 9
TIMING SYSTEM
9.1 Timer Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
9.2 Input Capture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
9.2.1 Timer Control 2 Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-5
9.2.2 Timer Input Capture Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-6
9.2.3 Timer Input Capture 4/Output Compare 5 Register . . . . . . . . . . . . . . . . . . . 9-6
9.3 Output Compare. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-6
9.3.1 Timer Output Compare Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
9.3.2 Timer Compare Force Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
9.3.3 Output Compare Mask Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
9.3.4 Output Compare 1 Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
9.3.5 Timer Counter Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
9.3.6 Timer Control 1 Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
9.3.7 Timer Interrupt Mask 1 Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
9.3.8 Timer Interrupt Flag 1 Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
TECHNICAL DATA
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Table of Contents (Cont.)
9.3.9 Timer Interrupt Mask 2 Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3.10 Timer Interrupt Flag 2 Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.4 Real-Time Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.4.1 Timer Interrupt Flag 2 Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.4.2 Pulse Accumulator Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.5 Computer Operating Properly Watchdog Function . . . . . . . . . . . . . . . . . . . . . . .
9.6 Pulse Accumulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.6.1 Pulse Accumulator Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.6.2 Pulse Accumulator Count Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.6.3 Pulse Accumulator Status and Interrupt Bits . . . . . . . . . . . . . . . . . . . . . . .
9-11
9-12
9-12
9-13
9-14
9-15
9-15
9-17
9-17
9-18
Appendix A
ELECTRICAL CHARACTERISTICS
Freescale Semiconductor, Inc...
Appendix B
MECHANICAL DATA AND ORDERING INFORMATION
B.1 Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
B.2 Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
B.3 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
Appendix C
DEVELOPMENT SUPPORT
C.1 Development System Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
C.2 MC68HC11D3 Development Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
INDEX
vi
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TECHNICAL DATA
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LIST OF ILLUSTRATIONS
Freescale Semiconductor, Inc...
Figure
Title
Page
1-1
MC68HC11D3 Block Diagram ........................................................................ 1-2
2-1
2-2
2-3
2-4
2-5
2-6
Pin Assignments for 44-Pin PLCC ................................................................. 2-1
Pin Assignments for 40-Pin DIP ..................................................................... 2-2
External Reset Circuit ..................................................................................... 2-3
Common Crystal Connections ........................................................................ 2-3
External Oscillator Connections ..................................................................... 2-4
One Crystal Driving Two MCUs ..................................................................... 2-4
3-1
3-2
Programming Model ....................................................................................... 3-1
Stacking Operations ....................................................................................... 3-3
4-1
4-2
4-3
Address/Data Demultiplexing ......................................................................... 4-2
MC68HC11D3 Memory Map .......................................................................... 4-3
RAM Standby MODB/VSTBY Connections ...................................................... 4-6
5-1
5-2
5-3
Processing Flow out of Reset (1 of 2) .......................................................... 5-12
Interrupt Priority Resolution (1 of 2) ............................................................. 5-14
Interrupt Source Resolution within SCI ........................................................ 5-16
7-1
7-2
7-3
7-4
SCI Transmitter Block Diagram ...................................................................... 7-2
SCI Receiver Block Diagram .......................................................................... 7-3
SCI Baud Rate Diagram ............................................................................... 7-10
Interrupt Source Resolution within SCI ........................................................ 7-12
8-1
8-2
SPI Block Diagram ......................................................................................... 8-2
SPI Transfer Format ....................................................................................... 8-3
9-1
9-2
9-3
Timer Clock Divider Chains ............................................................................ 9-2
Capture/Compare Block Diagram .................................................................. 9-4
Pulse Accumulator ....................................................................................... 9-16
A-1
A-2
A-3
A-4
A-5
A-6
A-7
A-8
A-9
Test Methods .................................................................................................. A-3
Timer Inputs ................................................................................................... A-4
POR and External Reset Timing Diagram ...................................................... A-5
STOP Recovery Timing Diagram ................................................................... A-6
WAIT Recovery Timing Diagram .................................................................... A-7
Port Write Timing Diagram ............................................................................. A-8
Port Read Timing Diagram ............................................................................. A-8
Multiplexed Expansion Bus Timing Diagram ................................................ A-10
SPI Master Timing (CPHA = 0) .................................................................... A-12
MC68HC11D3
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LIST OF ILLUSTRATIONS
Figure
(Continued)
Title
Page
SPI Master Timing (CPHA = 1) .................................................................... A-12
SPI Slave Timing (CPHA = 0) ...................................................................... A-13
SPI Slave Timing (CPHA = 1) ...................................................................... A-13
B-1
B-2
B-3
40-Pin DIP ...................................................................................................... B-1
44-Pin PLCC .................................................................................................. B-2
44-Pin QFP ..................................................................................................... B-3
Freescale Semiconductor, Inc...
A-10
A-11
A-12
TECHNI
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LIST OF TABLES
Table
Title
Page
2-1 Port Signal Functions............................................................................................. 2-6
Freescale Semiconductor, Inc...
3-2 Instruction Set........................................................................................................ 3-8
4-1
4-2
4-3
4-4
Register and Control Bit Assignments ................................................................. 4-4
Hardware Mode Select Summary.......................................................................... 4-6
RAM Mapping ........................................................................................................ 4-9
Register Mapping................................................................................................... 4-9
5-1
5-2
5-3
5-4
5-5
COP Time-out........................................................................................................ 5-2
Reset Cause, Reset Vector, and Operating Mode ................................................ 5-4
Highest Priority Interrupt Selection ........................................................................ 5-8
Interrupt and Reset Vector Assignments ............................................................... 5-9
Stacking Order on Entry to Interrupts .................................................................. 5-10
7-1 Baud Rate Prescale Selects .................................................................................. 7-8
7-2 Baud Rate Selects ................................................................................................ 7-9
9-1 Timer Summary ..................................................................................................... 9-3
9-2 Timer Control Configuration................................................................................... 9-5
9-3 Pulse Accumulator Timing ................................................................................... 9-16
A-1
A-2
A-3
A-4
A-5
A-6
A-7
Maximum Ratings.................................................................................................. A-1
Thermal Characteristics ........................................................................................ A-1
DC Electrical Characteristics................................................................................. A-2
Control Timing .......................................................................................................A-4
Peripheral Port Timing........................................................................................... A-8
Expansion Bus Timing........................................................................................... A-9
Serial Peripheral Interface Timing ....................................................................... A-11
B-1 Ordering Information ............................................................................................. B-3
MC68HC11D3
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SECTION 1
INTRODUCTION
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The MC68HC11D3 and MC68HC11D0 are ROM-based high-performance microcontrollers (MCUs) based on the MC68HC11E9 design. Members of the Dx series are derived from the same mask and feature a high speed multiplexed bus capable of
running at up to 3 MHz, and a fully static design that allows operations at frequencies
to dc.
The only difference between the MCUs in the Dx series is whether or not the ROM has
been tested and guaranteed.
1.1 Features
• MC68HC11 CPU
• Power Saving STOP and WAIT Modes
• 4 Kbytes of On-Chip ROM
• 192 Bytes of On-Chip RAM (All Saved During Standby)
• 16-Bit Timer System
— 3 Input Capture (IC) Channels
— 4 Output Compare (OC) Channels
— One IC or OC Channel (Software Selectable)
• 8-Bit Pulse Accumulator
• Real-Time Interrupt Circuit
• Computer Operating Properly (COP) Watchdog System
• Synchronous Serial Peripheral Interface (SPI)
• Asynchronous Nonreturn to Zero (NRZ) Serial Communications Interface (SCI)
• 26 Input/Output (I/O) Pins
— 16 Bidirectional I/O Pins
— 3 Input Only Pins
— 3 Output Only Pins (One Output Only Pin in the 40-Pin Package)
• Available in a 44-Pin Plastic Leaded Chip Carrier (PLCC) and 40-Pin Dual In-Line
Package (DIP)
1.2 Structure
Refer to Figure 1-1, which shows the structure of the MC68HC11D3 MCU.
INTRODUCTION
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1-1
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XIRQ
RESET
4 KBYTES ROM
INTERRUPT LOGIC
CPU
STROBE AND HANDSHAKE
PARALLEL I/O
SCI
CONTROL
PORT C
PORT D
PD7/R/W
PD6/AS
CONTROL
PORT B
PC7/A7/D7
PC6/A6/D6
PC5/A5/D5
PC4/A4/D4
PC3/A3/D3
PC2/A2/D2
PC1/A1/D1
PC0/A0/D0
CONTROL
PB7/A15
PB6/A14
PB5/A13
PB4/A12
PB3/A11
PB2/A10
PB1/A9
PB0/A8
PA7/PAI/OC1
PA6/OC2/OC1
PA5/OC3/OC1
PA4/OC4/OC1
PA3/OC5/OC1
PA2/IC1
PA1/IC2
PA0/IC3
SPI
TxD
RxD
ADDRESS/DATA
VSS
PD1/TxD
PD0/RxD
BUS EXPANSION
ADDRESS
TIMER
SYSTEM
PORT A
VDD
192 BYTES RAM
SS
SCK
MOSI
MISO
PERIODIC INTERRUPT
COP
PULSE ACCUMULATOR
IRQ/
E
OSCILLATOR
CLOCK LOGIC
MODE
CONTROL
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XTAL EXTAL
PD5/SS
PD4/SCK
PD3/MOSI
PD2/MISO
MODB/
VSTBY
R/W
AS
MODA/
LIR
Figure 1-1 MC68HC11D3 Block Diagram
INTRODUCTION
1-2
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TECHNICAL DATA
SECTION 2
PIN DESCRIPTIONS
E
MODA/LIR
MODB/VSTBY
42
41
40
EXTAL
VSS
2
43
PC0/ADDR0
3
XTAL
PC1/ADDR1
4
44
PC2/ADDR2
5
EVSS
PC3/ADDR3
6
The MC68HC11D3 is available packaged as a 40-pin dual in-line package (DIP), a 44pin plastic leaded chip carrier (PLCC), or a 44-pin quad flat pack (QFP). Most pins on
this MCU serve two or more functions, as described in the following paragraphs. Refer
to Figure 2-1 and Figure 2-2, which shows the MC68HC11D3 pin assignments.
7
39
PB0/ADDR8
PC5/ADDR5
8
38
PB1/ADDR9
PC6/ADDR6
9
37
PB2/ADDR10
PC7/ADDR7
10
36
PB3/ADDR11
XIRQ/VPP
11
35
PB4/ADDR12
PD7/R/W
12
34
PB5/ADDR13
PD6/AS
13
33
PB6/ADDR14
RESET
14
32
PB7/ADDR15
1
PC4/ADDR4
MC68HC(7)11D3
24
25
26
27
28
PA6/OC2/OC1
PA5/OC3/OC1
PA4/OC4/OC1
PA3/IC4/OC5/OC1
PA2/IC1
23
22
VDD
PA7/PAI/OC1
21
PD5/SS
PA1/IC2
20
PD1/TxD
29
19
PA0/IC3
17
PD4/SCK
NC
30
PD3/MOSI
31
16
18
15
PD2/MISO
IRQ
PD0/RxD
Figure 2-1 Pin Assignments for 44-Pin PLCC
Freescale Semiconductor, nc...
I
PIN DESCRIPTIONS
TECHNICAL DATA
2-1
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VSS
1
40
XTAL
PC0/ADDR0
2
39
EXTAL
PC1/ADDR1
3
38
E
PC2/ADDR2
4
37
MODA/LIR
PC3/ADDR3
5
36
MODB/VSTBY
PC4/ADDR4
6
35
PB0/ADDR8
PC5/ADDR5
7
34
PB1/ADDR9
PC6/ADDR6
8
33
PB2/ADDR10
PC7/ADDR7
9
32
PB3/ADDR11
XIRQ/VPP
10
31
PB4/ADDR12
PD7/R/W
11
30
PB5/ADDR13
PD6/AS
12
29
PB6/ADDR14
RESET
13
28
PB7/ADDR15
IRQ
14
27
PA0/IC3
PD0/RxD
15
26
PA1/IC2
PD1/TxD
16
25
PA2/IC1
17
24
PA3/IC4/OC5/OC1
PD3/MOSI
18
23
PA5/OC3/OC1
PD4/SCK
19
22
PA7/PAI/OC1
20
21
VDD
PD2/MISO
PD5/SS
MC68HC(7)11D3
D3 40-PIN DIP
Figure 2-2 Pin Assignments for 40-Pin DIP
2.1 VDD, VSS, and EVSS
Power is supplied to the MCU through VDD and VSS. VSS is the power supply, and
VSS is ground. EVSS, available on the 44-pin PLCC, is an additional ground pin that
must be grounded with VSS. The MCU operates from a single 5-volt (nominal) power
supply. Very fast signal transitions occur on the MCU pins. The short rise and fall times
place high, short duration current demands on the power supply. To prevent noise
problems, provide good power supply bypassing at the MCU. Also, use bypass capacitors that have good high-frequency characteristics and situate them as close to the
MCU as possible. Bypass requirements vary, depending on how heavily the MCU pins
are loaded.
2.2 Reset (RESET)
An active low bidirectional control signal, RESET, acts as an input to initialize the MCU
to a known startup state. It also acts as an open-drain output to indicate that an internal
failure has been detected in either the clock monitor or COP watchdog circuit. The
CPU distinguishes between internal and external reset conditions by sensing whether
the reset pin rises to a logic one in less than two E-clock cycles after a reset has occurred. It is not advisable to connect an external resistor-capacitor (RC) power-up delay circuit to the reset pin of M68HC11 devices because the circuit charge time
PIN DESCRIPTIONS
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constant can cause the device to misinterpret the type of reset that occurred. Refer to
SECTION 5 RESETS AND INTERRUPTS for further information.
Figure 2-3 illustrates a reset circuit that uses an external switch. Use a low voltage
interrupt circuit, however, to prevent corruption of RAM.
VDD
VDD
4.7 k Ω
2
IN
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RESET
MC34(0/1)64
1
TO RESET
OF M68HC11
GND
3
EXT RESET CIRCUIT
Figure 2-3 External Reset Circuit
2.3 Crystal Driver and External Clock Input (XTAL, EXTAL)
These two pins provide the interface for either a crystal or a CMOS compatible clock
to control the internal clock generator circuitry. The frequency applied to these pins is
four times higher than the desired E-clock rate.
The XTAL pin is normally left unterminated when an external CMOS compatible clock
input is connected to the EXTAL pin. However, a 10 kΩ to 100 kΩ load resistor connected from XTAL to ground can be used to reduce RFI noise emission. The XTAL
output is normally intended to drive only a crystal. The XTAL output can be buffered
with a high impedance buffer, or it can be used to drive the EXTAL input of another
M68HC11.
In all cases, use caution around the oscillator pins. Load capacitances shown in the
oscillator circuits include all stray layout capacitances. Refer to Figure 2-4, Figure 25, and Figure 2-6.
25 pF *
EXTAL
10 MΩ
MCU
4xE
CRYSTAL
25 pF *
XTAL
* THIS VALUE INCLUDES ALL STRAY CAPACITANCES.
COMMON XTAL CONN
Figure 2-4 Common Crystal Connections
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4xE
CMOS-COMPATIBLE
EXTERNAL OSCILLATOR
EXTAL
MCU
XTAL
NC
EXT EXTAL CONN
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Figure 2-5 External Oscillator Connections
25 pF *
220 Ω
EXTAL
EXTAL
FIRST
MCU
10 MΩ
SECOND
MCU
4xE
CRYSTAL
25 pF *
XTAL
NC
XTAL
* THIS VALUE INCLUDES ALL STRAY CAPACITANCES.
DUAL-MCU XTAL CONN
Figure 2-6 One Crystal Driving Two MCUs
2.4 E-Clock Output (E)
E is the output connection for the internally generated E clock. The signal from E is
used as a timing reference. The frequency of the E-clock output is one fourth that of
the input frequency at the XTAL and EXTAL pins. When E-clock output is low, an internal process is taking place. When it is high, data is being accessed. All clocks, including the E clock, are halted when the MCU is in STOP mode. The E clock can be
turned off in single-chip modes to reduce the effects of radio frequency interference
(RFI).
2.5 Interrupt Request (IRQ)
The IRQ input provides a means of applying asynchronous interrupt requests to the
MCU. Either negative edge-sensitive triggering or level-sensitive triggering is program
selectable (OPTION register). IRQ is always configured to level-sensitive triggering at
reset. Connect an external pullup resistor, typically 4.7 kΩ, to VDD when IRQ is used
in a level sensitive wired-OR configuration.
2.6 Non-Maskable Interrupt (XIRQ)
The XIRQ input provides a means of requesting a nonmaskable interrupt after reset
initialization. During reset, the X bit in the condition code register (CCR) is set and any
interrupt is masked until MCU software enables it. Because the XIRQ input is levelPIN DESCRIPTIONS
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sensitive, it can be connected to a multiple-source wired-OR network with an external
pullup resistor to VDD. XIRQ is often used as a power loss detect interrupt.
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Whenever XIRQ or IRQ are used with multiple interrupt sources (IRQ must be configured for level-sensitive operation if there is more than one source of IRQ interrupt),
each source must drive the interrupt input with an open-drain type of driver to avoid
contention between outputs. There should be a single pullup resistor near the MCU
interrupt input pin (typically 4.7 kΩ). There must also be an interlock mechanism at
each interrupt source so that the source holds the interrupt line low until the MCU recognizes and acknowledges the interrupt request. If one or more interrupt sources are
still pending after the MCU services a request, the interrupt line will still be held low
and the MCU will be interrupted again as soon as the interrupt mask bit in the MCU is
cleared (normally upon return from an interrupt). Refer to SECTION 5 RESETS AND
INTERRUPTS.
2.7 MODA and MODB (MODA/LIR,and MODB/VSTBY)
During reset, MODA and MODB select one of the four operating modes. Refer to SECTION 4 OPERATING MODES AND ON-CHIP MEMORY.
After the operating mode has been selected, the LIR pin provides an open-drain output
to indicate that execution of an instruction has begun. A series of E-clock cycles occurs
during execution of each instruction. The LIR signal goes low during the first E-clock
cycle of each instruction (opcode fetch). This output is provided for assistance in program debugging.
The VSTBY pin is used to input RAM standby power. When the voltage on this pin is
more than one MOS threshold (about 0.7 volts) above the VDD voltage, the internal
192-byte RAM and part of the reset logic are powered from this signal rather than the
VDD input. This allows RAM contents to be retained without VDD power applied to the
MCU. Reset must be driven low before VDD is removed and must remain low until VDD
has been restored to a valid level.
2.8 PD6/AS
This pin performs either of two separate functions, depending on the operating mode.
In single-chip and bootstrap modes, the pin functions as input/output port D bit 6. In
the expanded multiplexed and test modes, it provides an address strobe (AS) function.
The AS can demultiplex the address and data signals at port C. Refer to SECTION 4
OPERATING MODES AND ON-CHIP MEMORY for further information.
2.9 PD7/R/W
This pin provides two separate functions, depending on the operating mode. In singlechip and bootstrap modes, PD7/R/W acts as input/output port D bit 7. Refer to SECTION 6 PARALLEL I/O for further information.
In expanded multiplexed and test modes, PD7/R/W performs a read/write function.
PD7/R/W controls the direction of transfers on the external data bus. A high on this pin
indicates that a read cycle is in progress.
PIN DESCRIPTIONS
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2.10 Port Signals
In the 44-pin PLCC package, 32 input/output lines are arranged into four 8-bit ports:
A, B, C, and D. The lines of ports B, C, and D are fully bidirectional. Each of these four
ports serves a purpose other than I/O, depending on the operating mode or peripheral
functions selected. Note that ports B, C, and two bits of port D are available for I/O
functions only in single-chip and bootstrap modes. Refer to Table 2-1 for details about
the 32 port signals' functions within different operating modes.
Table 2-1 Port Signal Functions
Port/Bit
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PA0
PA1
PA2
PA3
PA4*
PA5
PA6*
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
Single-Chip and
Bootstrap Mode
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
PD6
PD7
Expanded Multiplexed and
Special Test Mode
PA0/IC3
PA1/IC2
PA2/IC1
PA3/OC5/IC4/OC1
PA4/OC4/OC1
PA5/OC3/OC1
PA6/OC2/OC1
PA7/PAI/OC1
ADDR8
ADDR9
ADDR10
ADDR11
ADDR12
ADDR13
ADDR14
ADDR15
ADDR0/DATA0
ADDR1/DATA1
ADDR2/DATA2
ADDR3/DATA3
ADDR4/DATA4
ADDR5/DATA5
ADDR6/DATA6
ADDR7/DATA7
PD0/RxD
PD1/TxD
PD2/MISO
PD3/MOSI
PD4/SCK
PD5/SS
AS
R/W
*In the 40-pin package, pins PA4 and PA6 are not bonded. Their associated I/O and output compare functions are
not available externally. They can still be used as internal software timers, however.
PIN DESCRIPTIONS
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2.10.1 Port A
Port A can be read at any time. Inputs return the pin level; outputs return the pin driver
input level. If written, port A stores the data in an internal latch. It drives the pins only
if they are configured as outputs. Writes to port A do not change the pin state when
the pins are configured for timer output compares.
Out of reset, port A bits 7 and [3:0] are general high impedance inputs, while bits [6:4]
are outputs, driving low. Bidirectional lines PA7 and PA3 in PACTL are not changed
and do not have any effect on those bits. When the output compare functions associated with these pins are disabled, the DDR bits in PACTL govern the I/O state.
Freescale Semiconductor, Inc...
Refer to SECTION 6 PARALLEL I/O.
2.10.2 Port B
Port B is an 8-bit general-purpose I/O port with a data register (PORTB) and a data
direction register (DDRB). In single-chip mode, port B pins are general-purpose I/O
pins (PB[7:0]). In the expanded multiplexed mode, all of the port B pins act as the highorder address bits (ADDR[15:8]) of the address bus.
Port B can be read at any time. Inputs return the sensed levels at the pin, while outputs
return the input level of the port B pin drivers. If port B is written, the data is stored in
an internal latch and can be driven only if port B is configured as general-purpose outputs in single-chip or bootstrap modes.
Port B pins are general-purpose inputs out of reset in single-chip and bootstrap
modes. These pins are outputs (the high order address bits) out of reset in expanded
multiplexed and test modes.
Refer to SECTION 6 PARALLEL I/O.
2.10.3 Port C
Port C is an 8-bit general-purpose I/O port with a data register (PORTC) and a data
direction register (DDRC). In the single-chip mode, port C pins are general-purpose I/
O pins (PC[7:0]). In the expanded multiplexed mode, port C pins are configured as
multiplexed address/data pins. During the address cycle, bits [7:0] of the address are
output on PC[7:0]. During the data cycle, bits [7:0] (PC[7:0]) are bidirectional data pins
controlled by the R/W signal.
Port C can be read at any time. Inputs return the sensed levels at the pin, while outputs
return the input level of the port C pin drivers. If port C is written, the data is stored in
an internal latch and can be driven only if port C is configured for general-purpose outputs in single-chip or bootstrap mode. Port C pins are general-purpose inputs out of
reset in single-chip and bootstrap modes. These pins are multiplexed low-order address and data bus lines out of reset in expanded multiplexed and test modes.
The CWOM control bit in the PIOC register disables port C's P-channel output driver.
CWOM simultaneously affects all eight bits of port C. Because the N-channel driver is
not affected by CWOM, setting CWOM causes port C to become an open-drain-type
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output port suitable for wired-OR operation. In wired-OR mode (a port C bit is at logic
level zero), it is actively driven low by the N-channel driver. When a port C bit is at logic
level one, the associated pin has high impedance, as neither the N- nor the P-channel
devices are active. It is customary to have an external pullup resistor on lines that are
driven by open-drain devices. Port C can only be configured for wired-OR operation
when the MCU is in single-chip mode. Refer to SECTION 6 PARALLEL I/O for additional information about port C functions.
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2.10.4 Port D
Port D, an 8-bit, general-purpose I/O port has a data register (PORTD) and a data direction register (DDRD). The eight port D bits (D[7:0]) can be used for general-purpose
I/O, for the serial communications interface (SCI) and serial peripheral interface (SPI)
subsystems, or for bus data direction control.
Port D can be read at any time and inputs return the sensed levels at the pin; whereas,
the outputs return the input level of the port D pin drivers. If PORTD is written, the data
is stored in an internal latch, and can be driven only if port D is configured for generalpurpose output. This port shares functions with the on-chip SCI and SPI subsystems,
while bits 6 and 7 control the direction of data flow on the bus in expanded and special
test modes.
Refer to SECTION 6 PARALLEL I/O.
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SECTION 3
CENTRAL PROCESSING UNIT
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This section presents information on M68HC11 central processing unit (CPU) architecture, data types, addressing modes, the instruction set, and special operations,
such as subroutine calls and interrupts.
The CPU is designed to treat all peripheral, I/O, and memory locations identically as
addresses in the 64 Kbyte memory map. This is referred to as memory-mapped I/O.
There are no special instructions for I/O that are separate from those used for memory.
This architecture also allows accessing an operand from an external memory location
with no execution-time penalty.
3.1 CPU Registers
M68HC11 CPU registers are an integral part of the CPU and are not addressed as if
they were memory locations. The seven registers, discussed in the following paragraphs, are shown in Figure 3-1.
7
15
A
0
7
0
0
B
D
8-BIT ACCUMULATORS A & B
OR 16-BIT DOUBLE ACCUMULATOR D
IX
INDEX REGISTER X
IY
INDEX REGISTER Y
SP
STACK POINTER
PROGRAM COUNTER
PC
7
S
0
X
H
I
N
Z
V
C
CONDITION CODES
CARRY/BORROW FROM MSB
OVERFLOW
ZERO
NEGATIVE
I-INTERRUPT MASK
HALF CARRY (FROM BIT 3)
X-INTERRUPT MASK
STOP DISABLE
HC11 PROG MODEL
Figure 3-1 Programming Model
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3.1.1 Accumulators A, B, and D
Accumulators A and B are general-purpose 8-bit registers that hold operands and results of arithmetic calculations or data manipulations. For some instructions, these two
accumulators are treated as a single double-byte (16-bit) accumulator called accumulator D. Although most operations can use accumulators A or B interchangeably, the
following exceptions apply:
The ABX and ABY instructions add the contents of 8-bit accumulator B to the contents
of 16-bit register X or Y, but there are no equivalent instructions that use A instead of B.
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The TAP and TPA instructions transfer data from accumulator A to the condition code
register, or from the condition code register to accumulator A, however there are no
equivalent instructions that use B rather than A.
The decimal adjust accumulator (DAA) instruction is used after binary-coded decimal
(BCD) arithmetic operations, but there is no equivalent BCD instruction to adjust accumulator B.
The add, subtract, and compare instructions associated with both A and B (ABA, SBA,
and CBA) only operate in one direction, making it important to plan ahead to ensure
the correct operand is in the correct accumulator.
3.1.2 Index Register X (IX)
The IX register provides a 16-bit indexing value that can be added to the 8-bit offset
provided in an instruction to create an effective address. The IX register can also be
used as a counter or as a temporary storage register.
3.1.3 Index Register Y (IY)
The 16-bit IY register performs an indexed mode function similar to that of the IX register. However, most instructions using the IY register require an extra byte of machine
code and an extra cycle of execution time because of the way the opcode map is implemented. Refer to 3.3 Opcodes and Operands for further information.
3.1.4 Stack Pointer (SP)
The M68HC11 CPU has an automatic program stack. This stack can be located anywhere in the address space and can be any size up to the amount of memory available
in the system. Normally the SP is initialized by one of the first instructions in an application program. The stack is configured as a data structure that grows downward from
high memory to low memory. Each time a new byte is pushed onto the stack, the SP
is decremented. Each time a byte is pulled from the stack, the SP is incremented. At
any given time, the SP holds the 16-bit address of the next free location in the stack.
Figure 3-2 is a summary of SP operations.
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WAI, WAIT FOR INTERRUPT
JSR, JUMP TO SUBROUTINE
7
MAIN PROGRAM
PC
$9D = JSR
$3E = WAI
CCR
SP+1
CCR
ACCB
SP+2
ACCB
SP+3
ACCA
SP+3
ACCA
MAIN PROGRAM
SP+4
IXH
SP+4
IXH
$AD = JSR
SP+5
IXL
SP+5
IXL
ff
SP+6
IYH
SP+6
IYH
NEXT MAIN INSTR.
SP+7
IYL
SP+7
IYL
SP+8
RTNH
SP+8
RTNH
➩ SP+9
RTNL
➩ SP+9
RTNL
PC
$18 = PRE
INDEXED, Y
$AD = JSR
RTN
SWI, SOFTWARE INTERRUPT
ff
NEXT MAIN INSTR.
PC
$3F = SWI
$BD = PRE
hh
INDEXED, Y
RTN
ll
7
MAIN PROGRAM
MAIN PROGRAM
PC
WAI, WAIT FOR INTERRUPT
PC
SP–8
CCR
SP–7
ACCB
SP–6
ACCA
SP–5
IXH
IXL
SP–3
IYH
$3E = WAI
SP–2
IYL
SP–1
RTNH
SP
RTNL
MAIN PROGRAM
$6E = JMP
ff
BSR, BRANCH TO SUBROUTINE
INDEXED, X
7
MAIN PROGRAM
NEXT MAIN INSTR.
PC
$8D = BSR
MAIN PROGRAM
$6E = JMP
ff
SP–1
RTNH
SP
RTNL
RTS, RETURN FROM
SUBROUTINE
PC
$39 = RTS
NEXT MAIN INSTR.
MAIN PROGRAM
7
STACK
0
SP
SP+1
RTNH
➩ SP+2
RTNL
$7E = JMP
hh
ll
EXTENDED
hh ll
0
➩ SP–2
MAIN PROGRAM
PC
STACK
$18 = PRE
INDEXED, Y
X + ff
0
➩ SP–9
MAIN PROGRAM
JMP, JUMP
PC
STACK
SP–4
NEXT MAIN INSTR.
X + ff
0
SP
SP+2
MAIN PROGRAM
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PC
STACK
SP+1
INDEXED, X
PC
7
INTERRUPT ROUTINE
dd
PC
RTN
SP
0
NEXT MAIN INSTR.
DIRECT
RTN
STACK
NEXT MAIN INSTR.
LEGEND:
RTN = ADDRESS OF NEXT INSTRUCTION IN MAIN PROGRAM TO
BE EXECUTED UPON RETURN FROM SUBROUTINE
RTNH = MOST SIGNIFICANT BYTE OF RETURN ADDRESS
RTNL = LEAST SIGNIFICANT BYTE OF RETURN ADDRESS
➩ = STACK POINTER POSITION AFTER OPERATION IS COMPLETE
dd = 8-BIT DIRECT ADDRESS ($0000–$00FF) (HIGH BYTE ASSUMED
TO BE $00)
ff = 8-BIT POSITIVE OFFSET $00 (0) TO $FF (256) IS ADDED TO INDEX
hh = HIGH-ORDER BYTE OF 16-BIT EXTENDED ADDRESS
ll = LOW-ORDER BYTE OF 16-BIT EXTENDED ADDRESS
rr= SIGNED RELATIVE OFFSET $80 (–128) TO $7F (+127) (OFFSET
RELATIVE TO THE ADDRESS FOLLOWING THE MACHINE CODE
OFFSET BYTE)
HC11 STACK OPERATIONS
Figure 3-2 Stacking Operations
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When a subroutine is called by a jump to subroutine (JSR) or branch to subroutine
(BSR) instruction, the address of the instruction after the JSR or BSR is automatically
pushed onto the stack, least significant byte first. When the subroutine is finished, a
return from subroutine (RTS) instruction is executed. The RTS pulls the previously
stacked return address from the stack, and loads it into the program counter. Execution then continues at this recovered return address.
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When an interrupt is recognized, the current instruction finishes normally, the return
address (the current value in the program counter) is pushed onto the stack, all of the
CPU registers are pushed onto the stack, and execution continues at the address
specified by the vector for the interrupt. At the end of the interrupt service routine, an
RTI instruction is executed. The RTI instruction causes the saved registers to be pulled
off the stack in reverse order. Program execution resumes at the return address.
There are instructions that push and pull the A and B accumulators and the X and Y
index registers. These instructions are often used to preserve program context. For example, pushing accumulator A onto the stack when entering a subroutine that uses accumulator A, and then pulling accumulator A off the stack just before leaving the
subroutine, ensures that the contents of a register will be the same after returning from
the subroutine as it was before starting the subroutine.
3.1.5 Program Counter (PC)
The program counter, a 16-bit register, contains the address of the next instruction to
be executed. After reset, the program counter is initialized from one of six possible
vectors, depending on operating mode and the cause of reset.
Table 3-1 Reset Vector Comparison
Normal
Test or Boot
POR or Pin
$FFFE, F
$BFFE, F
Clock Monitor
$FFFC, D
$BFFC, D
COP Watchdog
$FFFA, B
$BFFA, B
3.1.6 Condition Code Register (CCR)
This 8-bit register contains five condition code indicators (C, V, Z, N, and H), two interrupt masking bits, (IRQ and XIRQ) and a stop disable bit (S). In the M68HC11 CPU,
condition codes are automatically updated by most instructions. For example, load accumulator A (LDAA) and store accumulator A (STAA) instructions automatically set or
clear the N, Z, and V condition code flags. Pushes, pulls, add B to X (ABX), add B to
Y (ABY), and transfer/exchange instructions do not affect the condition codes. Refer
to Table 3-2, which shows what condition codes are affected by a particular instruction.
3.1.6.1 Carry/Borrow (C)
The C bit is set if the arithmetic logic unit (ALU) performs a carry or borrow during an
arithmetic operation. The C bit also acts as an error flag for multiply and divide opera-
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tions. Shift and rotate instructions operate with and through the carry bit to facilitate
multiple-word shift operations.
3.1.6.2 Overflow (V)
The overflow bit is set if an operation causes an arithmetic overflow. Otherwise, the V
bit is cleared.
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3.1.6.3 Zero (Z)
The Z bit is set if the result of an arithmetic, logic, or data manipulation operation is
zero. Otherwise, the Z bit is cleared. Compare instructions do an internal implied subtraction and the condition codes, including Z, reflect the results of that subtraction. A
few operations (INX, DEX, INY, and DEY) affect the Z bit and no other condition flags.
For these operations, only = and - conditions can be determined.
3.1.6.4 Negative (N)
The N bit is set if the result of an arithmetic, logic, or data manipulation operation is
negative (MSB = 1). Otherwise, the N bit is cleared. A result is said to be negative if its
most significant bit (MSB) is a one. A quick way to test whether the contents of a memory location has the MSB set is to load it into an accumulator and then check the status
of the N bit.
3.1.6.5 Interrupt Mask (I)
The interrupt request (IRQ) mask (I bit) is a global mask that disables all maskable interrupt sources. While the I bit is set, interrupts can become pending, but the operation
of the CPU continues uninterrupted until the I bit is cleared. After any reset, the I bit is
set by default and can only be cleared by a software instruction. When an interrupt is
recognized, the I bit is set after the registers are stacked, but before the interrupt vector
is fetched. After the interrupt has been serviced, a return from interrupt instruction is
normally executed, restoring the registers to the values that were present before the
interrupt occurred. Normally, the I bit is zero after a return from interrupt is executed.
Although the I bit can be cleared within an interrupt service routine, “nesting” interrupts
in this way should only be done when there is a clear understanding of latency and of
the arbitration mechanism. Refer to SECTION 5 RESETS AND INTERRUPTS.
3.1.6.6 Half Carry (H)
The H bit is set when a carry occurs between bits 3 and 4 of the arithmetic logic unit
during an ADD, ABA, or ADC instruction. Otherwise, the H bit is cleared. Half carry is
used during BCD operations.
3.1.6.7 X Interrupt Mask (X)
The XIRQ mask (X) bit disables interrupts from the pin. After any reset, X is set by default and must be cleared by a software instruction. When an interrupt is recognized,
the X and I bits are set after the registers are stacked, but before the interrupt vector
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terrupt occurred. The X interrupt mask bit is set only by hardware (or acknowledge). X
is cleared only by program instruction (TAP, where the associated bit of A is 0; or RTI,
where bit 6 of the value loaded into the CCR from the stack has been cleared). There
is no hardware action for clearing X.
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3.1.6.8 Stop Disable (S)
Setting the STOP disable (S) bit prevents the STOP instruction from putting the
M68HC11 into a low-power stop condition. If the STOP instruction is encountered by
the CPU while the S bit is set, it is treated as a no-operation (NOP) instruction, and
processing continues to the next instruction. S is set by reset —STOP disabled by default.
3.2 Data Types
The M68HC11 CPU supports the following data types:
• Bit data
• 8-bit and 16-bit signed and unsigned integers
• 16-bit unsigned fractions
• 16-bit addresses
A byte is eight bits wide and can be accessed at any byte location. A word is composed
of two consecutive bytes with the most significant byte at the lower value address. Because the M68HC11 is an 8-bit CPU, there are no special requirements for alignment
of instructions or operands.
3.3 Opcodes and Operands
The M68HC11 family of microcontrollers uses 8-bit opcodes. Each opcode identifies
a particular instruction and associated addressing mode to the CPU. Several opcodes
are required to provide each instruction with a range of addressing capabilities. Only
256 opcodes would be available if the range of values were restricted to the number
able to be expressed in 8-bit binary numbers.
A four-page opcode map has been implemented to expand the number of instructions.
An additional byte, called a prebyte, directs the processor from page 0 of the opcode
map to one of the other three pages. As its name implies, the additional byte precedes
the opcode.
A complete instruction consists of a prebyte, if any, an opcode, and zero, one, two, or
three operands. The operands contain information the CPU needs for executing the
instruction. Complete instructions can be from one to five bytes long.
3.4 Addressing Modes
Six addressing modes; immediate, direct, extended, indexed, inherent, and relative,
detailed in the following paragraphs, can be used to access memory. All modes except
inherent mode use an effective address. The effective address is the memory address
from which the argument is fetched or stored, or the address from which execution is
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to proceed. The effective address can be specified within an instruction, or it can be
calculated.
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3.4.1 Immediate
In the immediate addressing mode an argument is contained in the byte(s) immediately following the opcode. The number of bytes following the opcode matches the size
of the register or memory location being operated on. There are two-, three-, and four(if prebyte is required) byte immediate instructions. The effective address is the address of the byte following the instruction.
3.4.2 Direct
In the direct addressing mode, the low-order byte of the operand address is contained
in a single byte following the opcode, and the high-order byte of the address is assumed to be $00. Addresses $00–$FF are thus accessed directly, using two-byte instructions. Execution time is reduced by eliminating the additional memory access
required for the high-order address byte. In most applications, this 256-byte area is reserved for frequently referenced data. In M68HC11 MCUs, the memory map can be
configured for combinations of internal registers, RAM or external memory to occupy
these addresses.
3.4.2.1 Extended
In the extended addressing mode, the effective address of the argument is contained
in two bytes following the opcode byte. These are three-byte instructions (or four-byte
instructions if a prebyte is required). One or two bytes are needed for the opcode and
two for the effective address.
3.4.2.2 Indexed
In the indexed addressing mode, an 8-bit unsigned offset contained in the instruction
is added to the value contained in an index register (IX or IY) — the sum is the effective
address. This addressing mode allows referencing any memory location in the 64
Kbyte address space. These are from two- to five-byte instructions, depending on
whether or not a prebyte is required.
3.4.2.3 Inherent
In the inherent addressing mode, all the information necessary to execute the instruction is contained in the opcode. Operations that use only the index registers or accumulators, as well as control instructions with no arguments, are included in this
addressing mode. These are one- or two-byte instructions.
3.4.2.4 Relative
The relative addressing mode is used only for branch instructions. If the branch condition is true, an 8-bit signed offset included in the instruction is added to the contents
of the program counter to form the effective branch address. Otherwise, control proceeds to the next instruction. These are usually two-byte instructions.
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3.5 Instruction Set
Refer to Table 3-2, which shows all the M68HC11 instructions in all possible addressing modes. For each instruction, the table shows the operand construction, the number
of machine code bytes, and execution time in CPU E-clock cycles.
Table 3-2 Instruction Set (Sheet 1 of 7)
Mnemonic
ABA
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ABX
ABY
ADCA (opr)
Operation
Add
Accumulators
Add B to X
Add B to Y
Add with Carry
to A
Description
Addressing
Mode
INH
A+B⇒A
IX + (00 : B) ⇒ IX
IY + (00 : B) ⇒ IY
A+M+C⇒A
ADCB (opr)
Add with Carry
to B
B+M+C⇒B
ADDA (opr)
Add Memory
to A
A+M⇒A
ADDB (opr)
Add Memory
to B
B+M⇒B
ADDD (opr)
Add 16-Bit to D D + (M : M + 1) ⇒ D
ANDA (opr)
AND A with
Memory
A•M⇒A
ANDB (opr)
AND B with
Memory
B•M⇒B
ASL (opr)
Arithmetic
Shift Left
C
ASLA
b0
b7
b0
Arithmetic
Shift Left B
C
ASLD
b7
Arithmetic
Shift Left A
C
ASLB
A
A
A
A
A
B
B
B
B
B
A
A
A
A
A
B
B
B
B
B
b7
b0
A
A
A
A
A
B
B
B
B
B
0
INH
INH
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
EXT
IND,X
IND,Y
Instruction
Opcode
Operand Cycles
1B
—
2
18
18
18
18
18
18
18
18
18
3A
3A
89
99
B9
A9
A9
C9
D9
F9
E9
E9
8B
9B
BB
AB
AB
CB
DB
FB
EB
EB
C3
D3
F3
E3
E3
84
94
B4
A4
A4
C4
D4
F4
E4
E4
78
68
68
—
—
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
hh ll
ff
ff
S
—
X
—
Condition Codes
H
I
N
Z
∆
∆
∆
—
V
∆
C
∆
3
4
2
3
4
4
5
2
3
4
4
5
2
3
4
4
5
2
3
4
4
5
4
5
6
6
7
2
3
4
4
5
2
3
4
4
5
6
6
7
—
—
—
—
—
—
—
—
∆
—
—
—
—
—
∆
—
—
∆
—
—
∆
—
—
∆
—
—
∆
—
∆
∆
∆
∆
—
—
∆
—
∆
∆
∆
∆
—
—
∆
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
∆
∆
A
INH
48
—
2
—
—
—
—
∆
∆
∆
∆
B
INH
58
—
2
—
—
—
—
∆
∆
∆
∆
INH
05
—
3
—
—
—
—
∆
∆
∆
∆
77
67
67
47
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
∆
∆
∆
∆
A
EXT
IND,X
IND,Y
INH
—
—
—
—
∆
∆
∆
∆
B
INH
57
—
2
—
—
—
—
∆
∆
∆
∆
REL
24
3
—
—
—
—
—
—
—
—
0
0
Arithmetic
Shift Left D
0
C b7 A b0 b7 B b0
ASR
Arithmetic
Shift Right
ASRA
Arithmetic
Shift Right A
ASRB
Arithmetic
Shift Right B
BCC (rel)
Branch if Carry
Clear
b7
b7
b7
b0 C
18
b0 C
b0 C
?C=0
rr
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Table 3-2 Instruction Set (Sheet 2 of 7)
Mnemonic
Description
BCLR (opr)
(msk)
Clear Bit(s)
M • (mm) ⇒ M
BCS (rel)
Branch if Carry
Set
Branch if =
Zero
Branch if ∆
Zero
Branch if >
Zero
Branch if
Higher
Branch if
Higher or
Same
Bit(s) Test A
with Memory
?C=1
BEQ (rel)
BGE (rel)
BGT (rel)
BHI (rel)
BHS (rel)
Addressing
Mode
DIR
IND,X
IND,Y
REL
Instruction
Opcode
Operand Cycles
6
15 dd mm
7
1D ff mm
8
18
1D ff mm
25 rr
3
S
—
X
—
Condition Codes
H
I
N
Z
∆
∆
—
—
V
0
C
—
—
—
—
—
—
—
—
—
?Z=1
REL
27
rr
3
—
—
—
—
—
—
—
—
?N⊕V=0
REL
2C
rr
3
—
—
—
—
—
—
—
—
? Z + (N ⊕ V) = 0
REL
2E
rr
3
—
—
—
—
—
—
—
—
?C+Z=0
REL
22
rr
3
—
—
—
—
—
—
—
—
?C=0
REL
24
rr
3
—
—
—
—
—
—
—
—
A
A
A
A
A
IMM
DIR
EXT
IND,X
IND,Y
ii
dd
hh ll
ff
ff
—
—
—
—
∆
∆
0
—
18
85
95
B5
A5
A5
B
B
B
B
B
IMM
DIR
EXT
IND,X
IND,Y
ii
dd
hh ll
ff
ff
—
—
—
—
∆
∆
0
—
18
C5
D5
F5
E5
E5
—
—
—
—
—
—
—
—
? Z + (N ⊕ V) = 1
REL
2F
rr
?C=1
REL
25
rr
3
—
—
—
—
—
—
—
—
?C+Z=1
REL
23
rr
3
—
—
—
—
—
—
—
—
?N⊕V=1
REL
2D
rr
3
—
—
—
—
—
—
—
—
?N=1
REL
2B
rr
3
—
—
—
—
—
—
—
—
?Z=0
REL
26
rr
3
—
—
—
—
—
—
—
—
BPL (rel)
Branch if ∆
Zero
Branch if
Lower
Branch if
Lower or
Same
Branch if <
Zero
Branch if
Minus
Branch if not =
Zero
Branch if Plus
2
3
4
4
5
2
3
4
4
5
3
?N=0
REL
2A
rr
—
—
—
—
—
—
—
—
BRA (rel)
Branch Always
?1=1
REL
20
rr
—
—
—
—
—
—
—
—
BRCLR(opr)
(msk)
(rel)
Branch if
Bit(s) Clear
? M • mm = 0
DIR
IND,X
IND,Y
dd mm rr
ff mm rr
ff mm rr
—
—
—
—
—
—
—
—
18
13
1F
1F
BRN (rel)
Branch Never
REL
21
rr
—
—
—
—
—
—
—
—
DIR
IND,X
IND,Y
dd mm rr
ff mm rr
ff mm rr
—
—
—
—
—
—
—
—
18
12
1E
1E
dd mm
ff mm
ff mm
—
—
—
—
∆
∆
0
—
18
14
1C
1C
—
—
—
—
—
—
—
—
BITA (opr)
Freescale Semiconductor, Inc...
Operation
BITB (opr)
BLE (rel)
BLO (rel)
BLS (rel)
BLT (rel)
BMI (rel)
BNE (rel)
Bit(s) Test B
with Memory
Branch if Bit(s)
BRSET(opr)
Set
(msk)
(rel)
BSET (opr)
(msk)
BSR (rel)
BVC (rel)
BVS (rel)
CBA
CLC
CLI
CLR (opr)
Set Bit(s)
Branch to
Subroutine
Branch if
Overflow Clear
Branch if
Overflow Set
Compare A to
B
Clear Carry Bit
Clear Interrupt
Mask
Clear Memory
Byte
A•M
B•M
See Figure 3–2
REL
8D
rr
3
3
6
7
8
3
6
7
8
6
7
8
6
?V=0
REL
28
rr
3
—
—
—
—
—
—
—
—
?V=1
REL
29
rr
3
—
—
—
—
—
—
—
—
A–B
INH
11
—
2
—
—
—
—
∆
∆
∆
∆
0⇒C
0⇒I
INH
0C
—
—
—
—
—
—
—
0
0E
—
2
2
—
INH
—
—
—
0
—
—
—
—
0⇒M
EXT
IND,X
IND,Y
7F
6F
6F
6
6
7
—
—
—
—
0
1
0
0
?1=0
? (M) • mm = 0
M + mm ⇒ M
DIR
IND,X
IND,Y
18
hh ll
ff
ff
CENTRAL PROCESSING UNIT
TECHNICAL DATA
For More Information On This Product,
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3-9
Freescale Semiconductor, Inc.
Table 3-2 Instruction Set (Sheet 3 of 7)
Mnemonic
CLRA
CLRB
CLV
Freescale Semiconductor, Inc...
CMPA (opr)
Operation
Clear
Accumulator A
Clear
Accumulator B
Clear Overflow
Flag
Compare A to
Memory
Description
0⇒A
Addressing
Mode
A
INH
0⇒B
B
0⇒V
A–M
COMA
COMB
CPD (opr)
—
—
—
0
1
0
0
INH
0A
—
2
—
—
—
—
—
—
0
—
81
91
B1
A1
A1
C1
D1
F1
E1
E1
73
63
63
43
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
hh ll
ff
ff
—
2
3
4
4
5
2
3
4
4
5
6
6
7
2
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
0
1
—
—
—
—
∆
∆
0
1
—
2
—
—
—
—
∆
∆
0
1
83
93
B3
A3
A3
8C
9C
BC
AC
AC
8C
9C
BC
AC
AC
19
jj kk
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
—
5
6
7
7
7
4
5
6
6
7
5
6
7
7
7
2
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
7A
6A
6A
4A
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
∆
∆
∆
—
—
—
—
—
∆
∆
∆
—
INH
$FF – M ⇒ M
D–M:M +1
C
0
—
B
Ones
Complement
Memory Byte
Ones
Complement
A
Ones
Complement
B
Compare D to
Memory 16-Bit
V
0
2
$FF – B ⇒ B
COM (opr)
Condition Codes
H
I
N
Z
—
—
0
1
—
A
B–M
X
—
5F
$FF – A ⇒ A
Compare B to
Memory
S
—
INH
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
EXT
IND,X
IND,Y
INH
CMPB (opr)
A
A
A
A
A
B
B
B
B
B
Instruction
Opcode
Operand Cycles
4F
—
2
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
INH
18
18
18
53
1A
1A
1A
1A
CD
CPX (opr)
Compare X to
Memory 16-Bit
IX – M : M + 1
CPY (opr)
Compare Y to
Memory 16-Bit
IY – M : M + 1
DAA
Decimal Adjust
A
Decrement
Memory Byte
Adjust Sum to BCD
Decrement
Accumulator
A
Decrement
Accumulator
B
Decrement
Stack Pointer
Decrement
Index Register
X
Decrement
Index Register
Y
Exclusive OR
A with Memory
A–1⇒A
A
EXT
IND,X
IND,Y
INH
B–1⇒B
B
INH
5A
—
2
—
—
—
—
∆
∆
∆
—
SP – 1 ⇒ SP
INH
34
—
3
—
—
—
—
—
—
—
—
IX – 1 ⇒ IX
INH
09
—
3
—
—
—
—
—
∆
—
—
IY – 1 ⇒ IY
INH
09
—
4
—
—
—
—
—
∆
—
—
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
—
2
3
4
4
5
2
3
4
4
5
41
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
—
∆
∆
∆
—
41
—
—
—
—
—
∆
0
∆
DEC (opr)
DECA
DECB
DES
DEX
DEY
EORA (opr)
M–1⇒M
A⊕M⇒A
EORB (opr)
Exclusive OR
B with Memory
B⊕M⇒B
FDIV
Fractional
Divide 16 by
16
Integer Divide
16 by 16
D / IX ⇒ IX; r ⇒ D
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
INH
D / IX ⇒ IX; r ⇒ D
INH
IDIV
A
A
A
A
A
B
B
B
B
B
CD
18
18
18
1A
18
18
18
18
18
88
98
B8
A8
A8
C8
D8
F8
E8
E8
03
02
CENTRAL PROCESSING UNIT
3-10
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TECHNICAL DATA
Freescale Semiconductor, Inc.
Table 3-2 Instruction Set (Sheet 4 of 7)
Mnemonic
INC (opr)
Increment
Memory Byte
M+1⇒M
INCA
Increment
Accumulator
A
Increment
Accumulator
B
Increment
Stack Pointer
Increment
Index Register
X
Increment
Index Register
Y
Jump
A+1⇒A
Addressing
Mode
EXT
IND,X
IND,Y
A
INH
B+1⇒B
B
INCB
INS
INX
INY
Freescale Semiconductor, Inc...
JMP (opr)
Operation
Description
—
∆
—
SP + 1 ⇒ SP
INH
31
—
3
—
—
—
—
—
—
—
—
IX + 1 ⇒ IX
INH
08
—
3
—
—
—
—
—
∆
—
—
IY + 1 ⇒ IY
INH
08
—
4
—
—
—
—
—
∆
—
—
hh ll
ff
ff
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
hh ll
ff
ff
—
3
3
4
5
6
6
7
2
3
4
4
5
2
3
4
4
5
3
4
5
5
6
3
4
5
5
6
3
4
5
5
6
4
5
6
6
6
6
6
7
2
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
LDD (opr)
Load Double
Accumulator
D
M ⇒ A,M + 1 ⇒ B
LDS (opr)
Load Stack
Pointer
M : M + 1 ⇒ SP
LDX (opr)
Load Index
Register
X
M : M + 1 ⇒ IX
LDY (opr)
Load Index
Register
Y
M : M + 1 ⇒ IY
LSL (opr)
Logical Shift
Left
C b7
C b7
C b7
b0
b0
b0
B
INH
58
—
2
—
—
—
—
∆
∆
∆
∆
INH
05
—
3
—
—
—
—
∆
∆
∆
∆
EXT
IND,X
IND,Y
INH
74
64
64
44
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
0
∆
∆
∆
—
—
—
—
0
∆
∆
∆
18
18
18
18
18
18
CD
18
18
18
1A
18
18
0
0
0
b0 C
A
b7
7E
6E
6E
9D
BD
AD
AD
86
96
B6
A6
A6
C6
D6
F6
E6
E6
CC
DC
FC
EC
EC
8E
9E
BE
AE
AE
CE
DE
FE
EE
EE
CE
DE
FE
EE
EE
78
68
68
48
A
0
C b7 A b0 b7 B b0
b7
18
EXT
IND,X
IND,Y
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
EXT
IND,X
IND,Y
INH
A
A
A
A
A
B
B
B
B
B
Logical Shift
Left Double
0
∆
∆
M⇒B
Logical Shift
Right A
∆
∆
Load
Accumulator
B
LSRA
∆
—
See Figure 3–2
0
—
—
LDAB (opr)
Logical Shift
Right
—
—
M⇒A
LSR (opr)
—
C
—
—
Load
Accumulator
A
LSLD
—
V
∆
2
LDAA (opr)
Logical Shift
Left B
Condition Codes
H
I
N
Z
∆
∆
—
—
—
See Figure 3–2
LSLB
X
—
5C
Jump to
Subroutine
Logical Shift
Left A
S
—
INH
JSR (opr)
LSLA
Instruction
Opcode
Operand Cycles
6
7C hh ll
6
6C ff
7
18
6C ff
4C
—
2
18
b0 C
CENTRAL PROCESSING UNIT
TECHNICAL DATA
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3-11
Freescale Semiconductor, Inc.
Table 3-2 Instruction Set (Sheet 5 of 7)
Mnemonic
LSRB
Logical Shift
Right B
LSRD
Logical Shift
Right Double
MUL
NEG (opr)
NEGA
NEGB
Freescale Semiconductor, Inc...
Operation
NOP
ORAA (opr)
Multiply 8 by 8
Two’s
Complement
Memory Byte
Two’s
Complement
A
Two’s
Complement
B
No operation
OR
Accumulator
A (Inclusive)
ORAB (opr)
OR
Accumulator
B (Inclusive)
PSHA
ROL (opr)
Push A onto
Stack
Push B onto
Stack
Push X onto
Stack (Lo
First)
Push Y onto
Stack (Lo
First)
Pull A from
Stack
Pull B from
Stack
Pull X From
Stack (Hi
First)
Pull Y from
Stack (Hi
First)
Rotate Left
ROLA
Rotate Left A
ROLB
Rotate Left B
ROR (opr)
Rotate Right
RORA
Rotate Right A
RORB
Rotate Right B
RTI
Return from
Interrupt
Return from
Subroutine
Subtract B
from A
PSHB
PSHX
PSHY
PULA
PULB
PULX
PULY
Description
0
0
b7
S
—
X
—
Condition Codes
H
I
N
Z
∆
—
—
0
V
∆
C
∆
INH
04
—
3
—
—
—
—
0
∆
∆
∆
3D
70
60
60
40
—
hh ll
ff
ff
—
10
6
6
7
2
—
—
—
—
—
—
—
—
—
∆
—
∆
—
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
2
—
—
—
—
∆
∆
∆
∆
—
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
—
2
2
3
4
4
5
2
3
4
4
5
3
—
—
—
—
—
—
—
—
—
∆
—
∆
—
0
—
—
—
—
—
—
∆
∆
0
—
—
—
—
—
—
—
—
—
b7 A b0 b7 B b0 C
A∗B⇒D
0–M⇒M
0–A⇒A
A
INH
EXT
IND,X
IND,Y
INH
0–B⇒B
B
INH
50
A
A
A
A
A
B+M⇒B
B
B
B
B
B
A ⇒ Stk,SP = SP – 1 A
INH
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
INH
01
8A
9A
BA
AA
AA
CA
DA
FA
EA
EA
36
B ⇒ Stk,SP = SP – 1 B
INH
37
—
3
—
—
—
—
—
—
—
—
IX ⇒ Stk,SP = SP – 2
INH
3C
—
4
—
—
—
—
—
—
—
—
IY ⇒ Stk,SP = SP – 2
INH
3C
—
5
—
—
—
—
—
—
—
—
SP = SP + 1, A ⇐ Stk A
INH
32
—
4
—
—
—
—
—
—
—
—
SP = SP + 1, B ⇐ Stk B
INH
33
—
4
—
—
—
—
—
—
—
—
SP = SP + 2, IX ⇐
Stk
INH
38
—
5
—
—
—
—
—
—
—
—
SP = SP + 2, IY ⇐
Stk
INH
18
38
—
6
—
—
—
—
—
—
—
—
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
∆
∆
∆
∆
18
79
69
69
49
—
—
—
—
∆
∆
∆
∆
No Operation
A+M⇒A
18
18
18
18
A
EXT
IND,X
IND,Y
INH
B
INH
59
—
2
—
—
—
—
∆
∆
∆
∆
76
66
66
46
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
∆
∆
∆
∆
A
EXT
IND,X
IND,Y
INH
—
—
—
—
∆
∆
∆
∆
B
INH
56
—
2
—
—
—
—
∆
∆
∆
∆
See Figure 3–2
INH
3B
—
12
∆
↓
∆
∆
∆
∆
∆
∆
See Figure 3–2
INH
39
—
5
—
—
—
—
—
—
—
—
A–B⇒A
INH
10
—
2
—
—
—
—
∆
∆
∆
∆
b0
C b7
b0
C b7
b7
b7
b7
SBA
Instruction
Opcode
Operand Cycles
54
—
2
b0 C
C b7
RTS
Addressing
Mode
B
INH
b0
b0 C
18
b0 C
b0 C
CENTRAL PROCESSING UNIT
3-12
For More Information On This Product,
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TECHNICAL DATA
Freescale Semiconductor, Inc.
Table 3-2 Instruction Set (Sheet 6 of 7)
Mnemonic
Description
SBCA (opr)
Subtract with
Carry from A
A–M–C⇒A
SBCB (opr)
Subtract with
Carry from B
B–M–C⇒B
SEC
SEI
Set Carry
Set Interrupt
Mask
Set Overflow
Flag
Store
Accumulator
A
1⇒C
1⇒I
SEV
STAA (opr)
Freescale Semiconductor, Inc...
Operation
1⇒V
A⇒M
STAB (opr)
Store
Accumulator
B
B⇒M
STD (opr)
Store
Accumulator
D
A ⇒ M, B ⇒ M + 1
STOP
Stop Internal
Clocks
Store Stack
Pointer
—
STS (opr)
Store Index
Register X
IX ⇒ M : M + 1
STY (opr)
Store Index
Register Y
IY ⇒ M : M + 1
SUBA (opr)
Subtract
Memory from
A
A–M⇒A
SUBB (opr)
Subtract
Memory from
B
B–M⇒B
SUBD (opr)
Subtract
Memory from
D
D–M:M+1⇒D
TAB
TAP
TBA
TEST
TPA
TST (opr)
TSTA
TSTB
A
A
A
A
B
B
B
B
SP ⇒ M : M + 1
STX (opr)
SWI
A
A
A
A
A
B
B
B
B
B
A
A
A
A
A
A
A
A
A
A
Software
See Figure 3–2
Interrupt
Transfer A to B
A⇒B
Transfer A to
A ⇒ CCR
CC Register
Transfer B to A
B⇒A
TEST (Only in Address Bus Counts
Test Modes)
Transfer CC
CCR ⇒ A
Register to A
Test for Zero
M–0
or Minus
Test A for Zero
or Minus
Test B for Zero
or Minus
Addressing
Mode
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
INH
INH
Instruction
Opcode
Operand Cycles
2
82 ii
3
92 dd
4
B2 hh ll
4
A2 ff
5
18
A2 ff
2
C2 ii
3
D2 dd
4
F2 hh ll
4
E2 ff
5
18
E2 ff
0D
—
2
0F
—
2
INH
0B
DIR
EXT
IND,X
IND,Y
DIR
EXT
IND,X
IND,Y
DIR
EXT
IND,X
IND,Y
INH
DIR
EXT
IND,X
IND,Y
DIR
EXT
IND,X
IND,Y
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
IMM
DIR
EXT
IND,X
IND,Y
INH
18
18
18
18
CD
18
18
1A
18
18
18
18
S
—
X
—
Condition Codes
H
I
N
Z
∆
∆
—
—
—
—
—
—
∆
—
—
—
—
—
—
—
1
V
∆
C
∆
∆
∆
∆
—
—
—
—
—
—
1
—
—
2
—
—
—
—
—
—
1
—
97
B7
A7
A7
D7
F7
E7
E7
DD
FD
ED
ED
CF
dd
hh ll
ff
ff
dd
hh ll
ff
ff
dd
hh ll
ff
ff
—
3
4
4
5
3
4
4
5
4
5
5
6
2
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
—
—
—
—
9F
BF
AF
AF
DF
FF
EF
EF
DF
FF
EF
EF
80
90
B0
A0
A0
C0
D0
F0
E0
E0
83
93
B3
A3
A3
3F
dd
hh ll
ff
ff
dd
hh ll
ff
ff
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
ii
dd
hh ll
ff
ff
jj kk
dd
hh ll
ff
ff
—
4
5
5
6
4
5
5
6
5
6
6
6
2
3
4
4
5
2
3
4
4
5
4
5
6
6
7
14
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
0
—
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
—
∆
∆
∆
∆
—
—
—
1
—
—
—
—
INH
INH
16
06
—
—
2
2
—
∆
—
↓
—
∆
—
∆
∆
∆
∆
∆
0
∆
—
∆
INH
INH
17
00
—
—
2
*
—
—
—
—
—
—
—
—
∆
—
∆
—
0
—
—
—
INH
07
—
2
—
—
—
—
—
—
—
—
7D
6D
6D
4D
hh ll
ff
ff
—
6
6
7
2
—
—
—
—
∆
∆
0
0
—
—
—
—
∆
∆
0
0
5D
—
2
—
—
—
—
∆
∆
0
0
A–0
A
EXT
IND,X
IND,Y
INH
B–0
B
INH
18
CENTRAL PROCESSING UNIT
TECHNICAL DATA
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Table 3-2 Instruction Set (Sheet 7 of 7)
Mnemonic
TSX
TSY
TXS
TYS
WAI
XGDX
Transfer Stack
Pointer to X
Transfer Stack
Pointer to Y
Transfer X to
Stack Pointer
Transfer Y to
Stack Pointer
Wait for
Interrupt
Exchange D
with X
Exchange D
with Y
Description
SP + 1 ⇒ IX
Addressing
Mode
INH
SP + 1 ⇒ IY
INH
IX – 1 ⇒ SP
INH
IY – 1 ⇒ SP
INH
Stack Regs & WAIT
Instruction
Opcode
Operand Cycles
30
—
3
18
S
—
X
—
Condition Codes
H
I
N
Z
—
—
—
—
V
—
C
—
30
—
4
—
—
—
—
—
—
—
—
35
—
3
—
—
—
—
—
—
—
—
35
—
4
—
—
—
—
—
—
—
—
INH
3E
—
**
—
—
—
—
—
—
—
—
IX ⇒ D, D ⇒ IX
INH
8F
—
3
—
—
—
—
—
—
—
—
IY ⇒ D, D ⇒ IY
INH
8F
—
4
—
—
—
—
—
—
—
—
18
18
Freescale Semiconductor, Inc...
XGDY
Operation
CENTRAL PROCESSING UNIT
3-14
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TECHNICAL DATA
Freescale Semiconductor, Inc.
SECTION 4
OPERATING MODES AND ON-CHIP MEMORY
Freescale Semiconductor, Inc...
This section contains information about the modes that define MC68HC11D3 operating conditions, and about the on-chip memory that allows the MCU to be configured
for various applications.
4.1 Operating Modes
The values of the mode select inputs MODB and MODA during reset determine the
operating mode. Single chip and expanded multiplexed are the normal modes. With
single-chip mode only on-board memory is available. Expanded multiplexed mode,
however, allows access to external memory. Each of these two normal modes is
paired with a special mode. Bootstrap, a variation of the single-chip mode, is a special
mode that executes a bootloader program in an internal bootstrap ROM. Test is a special mode that allows privileged access to internal resources.
4.1.1 Single-Chip Mode
In single-chip mode, ports B and C are available for general-purpose parallel I/O. In
expanded multiplexed mode the MCU can access a 64 Kbyte address space. The total
address space includes the same on-chip memory addresses used for single-chip
mode plus external memory and peripheral devices.
4.1.2 Expanded Multiplexed Mode
Expanded memory access is achieved by providing multiplexed external data and address buses on two of the M68HC11 ports; therefore only 18 pins are needed for an
8-bit data bus, a 16-bit address bus and two bus control lines. Port B is designated for
ADDR[15:8], while port C is multiplexed ADDR[7:0]/DATA[7:0]. The address, R/W,
and AS signals are active and valid for all bus cycles including accesses to internal
memory locations. Refer to Figure 4-1, which illustrates a recommended method of
demultiplexing low order addresses from data at port C.
OPERATING MODES AND ON-CHIP MEMORY
TECHNICAL DATA
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4-1
Freescale Semiconductor, Inc.
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
ADDR15
ADDR14
ADDR13
ADDR12
ADDR11
ADDR10
ADDR9
ADDR8
HC373
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
AS
Freescale Semiconductor, Inc...
R/W
E
D1
D2
D3
D4
D5
D6
D7
D8
LE
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
OE
ADDR7
ADDR6
ADDR5
ADDR4
ADDR3
ADDR2
ADDR1
ADDR0
WE
OE
MCU
DATA7
DATA6
DATA5
DATA4
DATA3
DATA2
DATA1
DATA0
ADDR/DATA DEMUX
Figure 4-1 Address/Data Demultiplexing
4.1.3 Special Test Mode
Special test, a variation of the expanded multiplexed mode, is primarily used during
Motorola's internal production testing; however, it is accessible for programming the
CONFIG register, and supporting emulation and debugging during development.
4.1.4 Bootstrap Mode
When the MCU is reset in special bootstrap mode, a small amount of on-chip ROM is
enabled at address $BF00–$BFFF. The ROM contains a bootloader program and a
special set of interrupt and reset vectors. The MCU fetches the reset vector, then executes the bootloader.
For normal use of the bootloader program, send $FF to the SCI receiver at either E
clock ÷16, or E clock ÷104 (1200 baud for E clock equals 2 MHz). Then download up
to 192 bytes of program data, which is put into RAM starting at $0040. These characters are echoed through the transmitter. When loading is complete, the program jumps
to location $0040 and begins executing the code. The bootloader program ends the
download after 192 bytes, or when the received data line is idle for at least four character times. Use of an external pullup resistor is required when using the SCI transmitter pin because port D pins are configured for wired-OR operation by the bootloader.
In bootstrap mode, the interrupt vectors are directed to RAM. This allows the use of
interrupts through a jump table. Refer to Freescale application note AN1060,
MC68HC11 Bootstrap Mode.
OPERATING MODES AND ON-CHIP MEMORY
4-2
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4.2 Memory Map
The operating mode determines memory mapping and whether memory is addressed
on- or off-chip. Refer to Figure 4-2, which illustrates the memory maps for each of the
four modes of operation. Memory locations for on-chip resources are the same for both
expanded multiplexed and single-chip modes. 192-byte RAM is mapped to $0040 after reset. It can be placed at any other 4K boundary ($x040) by writing an appropriate
value to the INIT register. The 64-byte register block is mapped to $0000 after reset
and can also be placed at any 4K boundary ($x000) by writing an appropriate value to
the INIT register. Refer to Table 4-1, which details the MCU register and control bit
assignments.
$0000
0000
64-BYTE REGISTER BLOCK
003F
0040
192 BYTES STATIC RAM
Freescale Semiconductor, Inc...
$0040
00FF
EXT
EXT
$7000
7000
4 KBYTES ROM
7FFF
EXT
BF00
BOOT
ROM
BFFF
BFC0
BFFF
SPECIAL MODES
INTERRUPT
VECTORS
4 KBYTES ROM
FFC0
$F000
F000
FFFF
FFFF
$FFFF
SINGLE
CHIP
EXPANDED
BOOTSTRAP
SPECIAL
TEST
FFFF
NORMAL
MODES
INTERRUPT
VECTORS
D3 MEM MAP
Figure 4-2 MC68HC11D3 Memory Map
OPERATING MODES AND ON-CHIP MEMORY
TECHNICAL DATA
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4-3
Freescale Semiconductor, Inc.
Table 4-1 Register and Control Bit Assignments
$0000
Bit 7
6
5
4
3
2
1
Bit 0
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
$0001
Reserved
$0002
CWOM
PIOC
$0003
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PORTC
$0004
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
PORTB
$0005
Freescale Semiconductor, Inc...
PORTA
Reserved
$0006
DDB7
DDB6
DDB5
DDB4
DDB3
DDB2
DDB1
DDB0
DDRB
$0007
DDC7
DDC6
DDC5
DDC4
DDC3
DDC2
DDC1
DDC0
DDRC
$0008
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
PORTD
$0009
DDD7
DDD6
DDD5
DDD4
DDD3
DDD2
DDD1
DDD0
DDRD
$000A
Reserved
$000B
FOC1
FOC2
FOC3
FOC4
FOC5
0
0
0
CFORC
$000C
OC1M7
OC1M6
OC1M5
OC1M4
OC1M3
0
0
0
OC1M
$000D
OC1D7
OC1D6
OC1D5
OC1D4
OC1D3
0
0
0
OC1D
$000E
Bit 15
14
13
12
11
10
9
Bit 8
TCNT (High)
$000F
Bit 7
6
5
4
3
2
1
Bit 0
TCNT (Low)
$0010
Bit 15
14
13
12
11
10
9
Bit 8
TIC1 (High)
$0011
Bit 7
6
5
4
3
2
1
Bit 0
TIC1 (Low)
$0012
Bit 15
14
13
12
11
10
9
Bit 8
TIC2 (High)
$0013
Bit 7
6
5
4
3
2
1
Bit 0
TIC2 (Low)
$0014
Bit 15
14
13
12
11
10
9
Bit 8
TIC3 (High)
$0015
Bit 7
6
5
4
3
2
1
Bit 0
TIC3 (Low)
$0016
Bit 15
14
13
12
11
10
9
Bit 8
TOC1(High)
$0017
Bit 7
6
5
4
3
2
1
Bit 0
TOC1 (Low)
$0018
Bit 15
14
13
12
11
10
9
Bit 8
TOC2 (High)
$0019
Bit 7
6
5
4
3
2
1
Bit 0
TOC2 (Low)
$001A
Bit 15
14
13
12
11
10
9
Bit 8
TOC3 (High)
$001B
Bit 7
6
5
4
3
2
1
Bit 0
TOC3 (Low)
$001C
Bit 15
14
13
12
11
10
9
Bit 8
TOC4 (High)
$001D
Bit 7
6
5
4
3
2
1
Bit 0
TOC4 (Low)
$0023
OC1F
OC2F
OC3F
OC4F
I4/O5F
IC1F
IC2F
IC3F
TFLG1
$0024
TOI
RTII
PAOVI
PAII
0
0
PR1
PR0
TMSK2
$0025
TOF
RTIF
PAOVF
PAIF
0
0
0
0
TFLG2
$0026
DDRA7
PAEN
PAMOD
PEDGE
DDRA3
I4/O5
RTR1
RTR0
PACTL
$0027
Bit 7
6
5
4
3
2
1
Bit 0
PACNT
$0028
SPIE
SPE
DWOM
MSTR
CPOL
CPHA
SPR1
SPR0
SPCR
$0029
SPIF
WCOL
0
MODF
0
0
0
0
SPSR
$002A
Bit 7
6
5
4
3
2
1
Bit 0
SPDR
OPERATING MODES AND ON-CHIP MEMORY
4-4
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TECHNICAL DATA
Freescale Semiconductor, Inc.
Table 4-1 Register and Control Bit Assignments (Continued)
Bit 7
6
5
4
3
2
1
Bit 0
$002B
TCLR
0
SCP1
SCP0
RCKB
SCR2
SCR1
SCR0
BAUD
$002C
R8
T8
0
M
WAKE
0
0
0
SCCR1
$002D
TIE
TCIE
RIE
ILIE
TE
RE
RWU
SBK
SCCR2
$002E
TDRE
TC
RDRF
IDLE
OR
NF
FE
0
SCSR
$002F
R7/T7
R6/T6
R5/T5
R4/T4
R3/T3
R2/T2
R1/T1
R0/T0
SCDR
$0030
Reserved
to
Freescale Semiconductor, Inc...
$0038
Reserved
$0039
0
0
IRQE
DLY
CME
0
CR1
CR0
OPTION
$003A
Bit 7
6
5
4
3
2
1
Bit 0
COPRST
$003B
Reserved
$003C
RBOOT
SMOD
MDA
IRVNE
PSEL3
PSEL2
PSEL1
PSEL0
HPRIO
$003D
RAM3
RAM2
RAM1
RAM0
REG3
REG2
REG1
REG0
INIT
$003E
TILOP
0
OCCR
CBYP
DISR
FCM
FCOP
0
TEST1
$003F
0
0
0
0
0
NOCOP
ROMON
0
CONFIG
The bootloader program is contained in the 192-byte bootstrap ROM. This ROM,
which appears as internal memory space at locations $BF40–$BFFF, is enabled only
if the MCU is reset in special bootstrap mode.
Memory locations are the same for expanded multiplexed and single-chip modes, except for ROM in expanded mode and the bootloader ROM in special bootstrap mode.
The on-board 192-byte RAM is initially located at $0040 after reset, but can be placed
at any other 4K boundary ($x040) by writing an appropriate value to the INIT register.
The 4 Kbyte ROM is located at $F000 through $FFFF in all modes except expanded
multiplexed, in which it is located at $7000. ROM can be located at $F000 in expanded
multiplexed by entering single-chip mode out of reset and setting the MDA bit in the
HPRIO register to 1, thereby entering expanded mode from internal ROM. Disable
ROM by clearing the ROMON bit in the CONFIG register.
Hardware priority is built into RAM and I/O remapping. Registers and RAM have priority over ROM. In the event of conflicts, the higher priority resource takes precedence.
The 192 bytes of fully static RAM store instructions, variables, and temporary data.
The direct addressing mode can access RAM locations using a one-byte address operand, saving program memory space and execution time, depending on the application. RAM contents are preserved during periods of processor inactivity by two
methods, both of which reduce power consumption.
In the software-based STOP mode, the clocks are stopped while VDD powers the
MCU. Because power supply current is directly related to operating frequency in
CMOS integrated circuits, only a very small amount of leakage exists when the clocks
are stopped.
OPERATING MODES AND ON-CHIP MEMORY
TECHNICAL DATA
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In the second method, the MODB/VSTBY pin can supply RAM power from a battery
backup or from a second power supply, as shown in Figure 4-3. Using the MODB/
VSTBY pin may require external hardware, but can be justified when a significant
amount of external circuitry is operating from VDD. If VSTBY is used to maintain RAM
contents, reset must be held low whenever VDD is below normal operating level. Refer
to SECTION 5 RESETS AND INTERRUPTS.
VDD
MAX
690
VDD
4.7k
TO MODB/VSTBY
OF M68HC11
Freescale Semiconductor, Inc...
VOUT
4.8 V
NiCd
VBATT
+
MODB/VSTBY CONN
Figure 4-3 RAM Standby MODB/VSTBY Connections
4.2.1 Priority and Mode Select Register
The four operating modes are selected with the logic states of the mode A (MODA)
and mode B (MODB) pins during reset. The MODA and MODB logic levels determine
the logic state of the special mode (SMOD) and mode A (MDA) control bits in the
HPRIO register.
After reset is released, the mode select pins no longer influence the MCU operating
mode. For single-chip mode, the MODA pin is connected to a logic zero. For expanded
mode, MODA is normally connected to VDD through a pull-up resistor of 4.7 kΩ. The
MODA pin also functions as the load instruction register (LIR) pin when the MCU is not
in reset. The open drain active low LIR output pin drives low during the first E cycle of
each instruction. The MODB pin also functions as standby power input, VSTBY, which
maintains RAM contents in the absence of VDD. Refer to Table 4-2 for information
about hardware mode selection.
Table 4-2 Hardware Mode Select Summary
Inputs
MODB
1
1
0
0
Mode
MODA
0
1
0
1
Single-Chip
Expanded Multiplexed
Special Bootstrap
Special Test
Latched at Reset
RBOOT SMOD
MDA
0
0
0
0
0
1
1
1
0
0
1
1
OPERATING MODES AND ON-CHIP MEMORY
4-6
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HPRIO — Highest Priority I-Bit Interrupt and Miscellaneous
RESET:
Bit 7
RBOOT
—
6
SMOD
—
5
MDA
—
4
IRVNE
—
3
PSEL3
0
$003C
2
PSEL2
1
1
PSEL1
0
Bit 0
PSEL0
1
The values of the RBOOT, SMOD, IRVNE, and MDA at reset depend on the mode during initialization. Refer to Table 4-2.
Freescale Semiconductor, Inc...
RBOOT — Read Bootstrap ROM
Has meaning only when the SMOD bit is a one (special bootstrap mode or special test
mode). At all other times this bit is clear and cannot be written.
0 = Bootloader ROM disabled and not in map
1 = Bootloader ROM enabled and located in map at $BF40–$BFFF
SMOD — Special Mode Select
This bit reflects the inverse of the MODB input pin at the rising edge of reset. It is set
if the MODB input pin is low during reset. If MODB is high during reset, it is cleared.
SMOD can be cleared under software control from the special modes, thus changing
the operating mode of the MCU. SMOD can never be set by software.
0 = Normal mode variation in effect
1 = Special mode variation in effect
MDA — Mode Select A
The mode select A bit reflects the status of the MODA input pin at the rising edge of
reset. While the SMOD bit is set (special bootstrap or special test mode in effect), the
MDA bit can be written, thus changing the operating mode of the MCU. When the
SMOD bit is clear, the MODA bit is read-only and the operating mode cannot be
changed without going through a reset sequence.
0 = Normal single-chip or special bootstrap mode in effect
1 = Normal expanded or special test mode in effect
IRVNE — Internal Read Visibility/Not E
The IRVNE control bit allows internal read accesses to be available on the external
data bus during factory testing or emulation. If this capability is used for other purposes, bus conflicts can occur because the bidirectional data bus is driven out during a
read of internal addresses, even though the R/W line suggests a high impedance
read mode.
0 = No internal read visibility on external bus
1 = Internal read data driven out data bus
In single-chip modes, this bit determines whether the E clock drives out of the chip.
0 = E driven out
1 = E pin driven low
OPERATING MODES AND ON-CHIP MEMORY
TECHNICAL DATA
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Mode
IRVNE Out
of Reset
0
0
0
1
Single-Chip
Expanded
Boot
Special Test
E Clock Out
of Reset
On
On
On
On
IRV Out of
Reset
Off
Off
Off
On
IRVNE
Affects Only
E
IRV
E
IRV
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PSEL[3:0] — Priority Select Bits
Refer to SECTION 5 RESETS AND INTERRUPTS.
4.2.2 System Initialization
Registers and bits that control initialization and the basic configuration of the MCU are
protected against writes except under special circumstances. The protection mechanism, overridden in special operating modes, permits writing these bits only within the
first 64 bus cycles after any reset, and then only once after each reset. If the MCU is
going to be changed to a normal mode after being reset in a special mode, write to the
protected registers before writing the SMOD control bit to zero.
4.2.2.1 CONFIG Register
The CONFIG register consists of static latches that control the startup configuration of
the MCU. CONFIG is writable only once in expanded and single-chip modes (SMOD
= 0). In these modes, the COP watchdog timer is enabled out of reset.
CONFIG — System Configuration
RESET:
Bit 7
0
0
6
0
0
5
0
0
$003F
4
0
0
3
0
0
2
NOCOP
—
1
ROMON
—
Bit 0
0
0
Bits [7:3] and 0 — Not implemented
Always read zero
NOCOP — COP System Disable
This bit is cleared out of reset in normal modes (COP enabled). Refer to SECTION 5
RESETS AND INTERRUPTS.
0 = COP system enabled
1 = COP system disabled
ROMON — ROM Enable
In all modes, ROMON is forced to one out of reset. Writable once in normal modes and
writable at any time in special modes.
0 = ROM removed from the memory map
1 = ROM present in the memory map
OPERATING MODES AND ON-CHIP MEMORY
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NOTE
In expanded mode, ROM is located at $7000–$7FFF out of reset. In
all other modes, ROM is located at $F000–$FFFF.
4.2.2.2 INIT Register
The internal registers used to control the operation of the MCU can be relocated on 4K
boundaries within the memory space with the use of INIT. This 8-bit special-purpose
register can change the default locations of the RAM and control registers within the
MCU memory map. It can be written to only once within the first 64 E-clock cycles after
a reset, and then it becomes a read-only register.
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INIT — RAM and I/O Mapping Register
RESET:
Bit 7
RAM3
0
6
RAM2
0
5
RAM1
0
$003D
4
RAM0
0
3
REG3
0
2
REG2
0
1
REG1
0
Bit 0
REG0
1
RAM[3:0] — RAM Map Position
These four bits, which specify the upper hexadecimal digit of the RAM address, control
position of RAM in the memory map. RAM can be positioned at the beginning of any
4K page in the memory map. It is initialized to address $0040 out of reset. Refer to
Table 4-3.
REG[3:0] — 64-Byte Register Block Position
These four bits specify the upper hexadecimal digit of the address for the 64-byte block
of internal registers. The register block, positioned at the beginning of any 4K page in
the memory map, is initialized to address $0000 out of reset. Refer to Table 4-4.
Table 4-3 RAM Mapping
RAM[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Address
$0040–$00FF
$1040–$10FF
$2040–$20FF
$3040–$30FF
$4040–$40FF
$5040–$50FF
$6040–$60FF
$7040–$70FF
$8040–$80FF
$9040–$90FF
$A040–$A0FF
$B040–$B0FF
$C040–$C0FF
$D040–$D0FF
$E040–$E0FF
$F040–$F0FF
Table 4-4 Register Mapping
REG[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Address
$0000–$003F
$1000–$103F
$2000–$203F
$3000–$303F
$4000–$403F
$5000–$503F
$6000–$603F
$7000–$703F
$8000–$803F
$9000–$903F
$A000–$A03F
$B000–$B03F
$C000–$C03F
$D000–$D03F
$E000–$E03F
$F000–$F03F
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4.2.2.3 OPTION Register
The 8-bit special-purpose OPTION register sets internal system configuration options
during initialization. The time protected control bits, IRQE, DLY, and CR[1:0] can be
written to only once after a reset and then they become read-only. This minimizes the
possibility of any accidental changes to the system configuration.
OPTION — System Configuration Options
RESET:
Bit 7
0
0
6
0
0
5
IRQE*
0
4
DLY*
1
$0039
3
CME
0
2
0
0
1
CR1*
0
Bit 0
CR0*
0
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*Can be written only once in first 64 cycles out of reset in normal modes, or at any time in special modes
Bits [7:6] and 2 — Not implemented
Always read zero
IRQE — IRQ Select Edge Sensitive only
0 = IRQ is configured for level sensitive operation
1 = IRQ is configured for edge sensitive only operation
DLY — Enable Oscillator Startup Delay
0 = The oscillator startup delay coming out of STOP is bypassed and the MCU resumes processing within about four bus cycles.
1 = A delay of approximately 4000 E-clock cycles is imposed as the MCU is started
up from the STOP power-saving mode. This delay allows the crystal oscillator
to stabilize.
CME — Clock Monitor Enable
Refer to SECTION 5 RESETS AND INTERRUPTS.
CR[1:0] — COP Timer Rate Select Bits
The internal E clock is first divided by 215 before it enters the COP watchdog system.
These control bits determine a scaling factor for the watchdog timer. Refer to SECTION 5 RESETS AND INTERRUPTS.
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SECTION 5
RESETS AND INTERRUPTS
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Resets and interrupt operations load the program counter with a vector that points to
a new location from which instructions are to be fetched. A reset immediately stops
execution of the current instruction and forces the program counter to a known starting
address. Internal registers and control bits are initialized so the MCU can resume executing instructions. An interrupt temporarily suspends normal program execution
while an interrupt service routine is being executed. After an interrupt has been serviced, the main program resumes as if there had been no interruption.
5.1 Resets
There are four possible sources of reset. Power-on reset (POR) and external reset
share the normal reset vector. The computer operating properly (COP) system and the
clock monitor each has its own vector.
5.1.1 Power-On Reset
A positive transition on VDD generates a power-on reset (POR), which is used only for
power-up conditions. POR cannot be used to detect drops in power supply voltages.
A 4064 tCYC (internal clock cycle) delay after the oscillator becomes active allows the
clock generator to stabilize. If RESET is at logical zero at the end of 4064 tCYC, the
CPU remains in the reset condition until goes to logical one.
It is important to protect the MCU during power transitions. Most M68HC11 systems
need an external circuit that holds the RESET pin low whenever VDD is below the minimum operating level. This external voltage level detector, or other external reset circuits, are the usual source of reset in a system. The POR circuit only initializes internal
circuitry during cold starts. Refer to Figure 2-3.
5.1.2 External Reset (RESET)
The CPU distinguishes between internal and external reset conditions by sensing
whether the reset pin rises to a logic one in less than two E-clock cycles after an internal device releases reset. When a reset condition is sensed, the RESET pin is driven
low by an internal device for four E-clock cycles, then released. Two E-clock cycles
later it is sampled. If the pin is still held low, the CPU assumes that an external reset
has occurred. If the pin is high, it indicates that the reset was initiated internally by either the COP system or the clock monitor. It is not advisable to connect an external
resistor capacitor (RC) power-up delay circuit to the reset pin of M68HC11 devices because the circuit charge time constant can cause the device to misinterpret the type of
reset that occurred.
5.1.3 COP Reset
The MCU includes a COP system to help protect against software failures. When the
RESETS AND INTERRUPTS
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COP is enabled, the software is responsible for keeping a free-running watchdog timer
from timing out. When the software is no longer being executed in the intended sequence, a system reset is initiated.
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The state of the NOCOP bit in the CONFIG register determines whether the COP system is enabled or disabled. In normal modes, COP is enabled out of reset and does
not depend on software action. To disable the COP system, set the NOCOP bit in the
CONFIG register. In the special test and bootstrap operating modes, the COP system
is initially inhibited by the disable resets (DISR) control bit in the TEST1 register. The
DISR bit can subsequently be written to zero to enable COP resets.
The COP timer rate control bits CR[1:0] in the OPTION register determine the COP
time-out period. The system E clock is divided by 215 and then further scaled by a factor shown in Table 5-1. After reset, these bits are zero, which selects the fastest timeout period. In normal operating modes, these bits can only be written once within 64
bus cycles after reset.
Table 5-1 COP Time-out
CR[1:0]
Divide
E/215
By
XTAL = 4.0 MHz
Time-out
–0/+32.8 ms
XTAL = 8.0 MHz
Time-out
–0/+16.4 ms
XTAL = 12.0 MHz
Time-out
–0/+10.9 ms
00
1
32.768 ms
16.384 ms
10.923 ms
01
4
131.072 ms
65.536 ms
43.691 ms
10
16
524.288 ms
262.140 ms
174.76 ms
64
2.097 sec
1.049 sec
699.05 ms
E=
1.0 MHz
2.0 MHz
3.0 MHz
11
COPRST — Am/Reset COP Timer Circuitry
RESET:
Bit 7
7
0
6
6
0
5
5
0
4
4
0
$003A
3
3
0
2
2
0
1
1
0
Bit 0
0
0
Complete the following reset sequence to service the COP timer. Write $55 to COPRST to arm the COP timer clearing mechanism. Then write $AA to COPRST to clear
the COP timer. Performing instructions between these two steps is possible as long as
both steps are completed in the correct sequence before the timer times out.
5.1.4 Clock Monitor Reset
The clock monitor circuit is based on an internal RC time delay. If no MCU clock edges
are detected within this RC time delay, the clock monitor can optionally generate a system reset. The clock monitor function is enabled or disabled by the CME control bit in
the OPTION register. The presence of a time-out is determined by the RC delay, which
allows the clock monitor to operate without any MCU clocks.
Clock monitor is used as a backup for the COP system. Because the COP needs a
clock to function, it is disabled when the clocks stop. Therefore, the clock monitor system can detect clock failures not detected by the COP system.
RESETS AND INTERRUPTS
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Semiconductor wafer processing causes variations of the RC time-out values between
individual devices. An E-clock frequency below 10 kHz is detected as a clock monitor
error. An E-clock frequency of 200 kHz or more prevents clock monitor errors. Using
the clock monitor function when the E clock is below 200 kHz is not recommended.
Special considerations are needed when a STOP instruction is executed and the clock
monitor is enabled. Because the STOP function causes the clocks to be halted, the
clock monitor function generates a reset sequence if it is enabled at the time the STOP
mode was initiated. Before executing a STOP instruction, clear the CME bit in the OPTION register to zero to disable the clock monitor. After recovery from STOP, set the
CME bit to logic one to enable the clock monitor.
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5.1.5 Option Register
OPTION — System Configuration Options
RESET:
Bit 7
0
0
6
0
0
5
IRQE*
0
4
DLY*
1
$0039
3
CME
0
2
0
0
1
CR1*
0
Bit 0
CR0*
0
*Can be written only once in first 64 cycles out of reset in normal modes, or at any time in special modes.
Bits [7:6] and 2 — Not implemented
Always read zero
IRQE — Configure IRQ for Edge Sensitive Only Operation
This bit can be written only once during the first 64 E-clock cycles after reset in normal
modes.
0 = Low level recognition
1 = Falling edge recognition
DLY — Enable Oscillator Startup Delay
This bit is set during reset and can be written only once during the first 64 E-clock cycles after reset in normal modes. If an external clock source rather than a crystal is
used, the stabilization delay can be inhibited because the clock source is assumed to
be stable.
0 = No stabilization delay on exit from STOP
1 = Stabilization delay enabled on exit from STOP
CME — Clock Monitor Enable
This control bit can be read or written at any time and controls whether or not the internal clock monitor circuit triggers a reset sequence when the system clock is slow or
absent. When it is clear, the clock monitor circuit is disabled. When it is set, the clock
monitor circuit is enabled. Reset clears the CME bit.
CR[1:0] — COP Timer Rate Select
These control bits determine a scaling factor for the watchdog timer.
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5.1.6 CONFIG Register
CONFIG — Configuration Control Register
RESET:
Bit 7
0
0
6
0
0
5
0
0
$003F
4
0
0
3
0
0
2
NOCOP
—
1
ROMON
—
Bit 0
0
0
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Bits [7:4] and 0 — Not implemented
Always read zero
NOCOP — COP System Disable
This bit is cleared out of reset in normal modes, enabling the COP system. It is set out
of reset in special modes. NOCOP is writable once in normal modes and at any time
in special modes.
0 = The COP system is enabled as the MCU comes out of reset.
1 = The COP system is disabled and does not generate system resets.
ROMON — Enable On-Chip ROM
Refer to SECTION 4 OPERATING MODES AND ON-CHIP MEMORY.
5.2 Effects of Reset
When a reset condition is recognized, the internal registers and control bits are forced
to an initial state. Depending on the cause of the reset and the operating mode, the
reset vector can be fetched from any of six possible locations. Refer to Table 5-2.
Table 5-2 Reset Cause, Reset Vector, and Operating Mode
Cause of Reset
Normal Mode Vector
Special Test or Bootstrap
POR or RESET Pin
$FFFE, FFFF
$BFFE, BFFF
Clock Monitor Failure
$FFFC, FFFD
$BFFC, $BFFD
COP Watchdog Time-out
$FFFA, FFFB
$BFFA, BFFB
These initial states then control on-chip peripheral systems to force them to known
startup states, as follows:
5.2.1 CPU
After reset, the CPU fetches the restart vector from the appropriate address during the
first three cycles, and begins executing instructions. The stack pointer and other CPU
registers are indeterminate immediately after reset; however, the X and I interrupt
mask bits in the condition code register (CCR) are set to mask any interrupt requests.
Also, the S bit in the CCR is set to inhibit the STOP mode.
5.2.2 Memory Map
After reset, the INIT register is initialized to $00, putting the 192 bytes of RAM at locations $0040 through $00FF, and the control registers at locations $0000 through
$003F.
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5.2.3 Parallel I/O
When a reset occurs in expanded multiplexed operating modes, the pins used for parallel I/O are dedicated to the expansion bus. In single-chip and bootstrap modes, all
ports are parallel I/O data ports. In expanded multiplexed and test modes, ports B, C,
and lines DATA6/AS and DATA7/R/W are a memory expansion bus with port B as a
high-order address bus, port C as a multiplexed address and data bus, AS as the demultiplexing signal, and R/as the data bus direction control. The CWOM bit in PIOC is
cleared so that port C is not in wired-OR mode. Port A, bits [0:3] and 7; and ports B,
C, and D are general-purpose I/O at reset and set for input. For this reason the pins
are configured as high impedance upon reset. Port A bits [4:6] are outputs, so high impedance protection is not necessary.
NOTE
Do not confuse pin function with the electrical state of the pin at reset.
All general-purpose I/O pins configured as inputs at reset are in a
high impedance state. Port data registers reflect the port's functional
state at reset. The pin function is mode dependent.
5.2.4 Timer
During reset, the timing system is initialized to a count of $0000. The prescaler bits are
cleared, and all output compare registers are initialized to $FFFF. All input capture registers are indeterminate after reset. The output compare 1 mask (OC1M) register is
cleared so that successful OC1 compares do not affect any I/O pins. The other four
output compares are configured so that they do not affect any I/O pins on successful
compares. All input capture edge-detector circuits are configured for capture disabled
operation. The timer overflow interrupt flag and all eight timer function interrupt flags
are cleared. All nine timer interrupts are disabled because their mask bits have been
cleared.
The I4/O5 bit in the PACTL register is cleared to configure the I4/O5 function as OC5;
however, the OM5:OL5 control bits in the TCTL1 register are clear so OC5 does not
control the PA3 pin.
5.2.5 Real-Time Interrupt
The real-time interrupt flag (RTIF) is cleared and automatic hardware interrupts are
masked. The rate control bits are cleared after reset and can be initialized by software
before the real-time interrupt (RTI) system is used. After reset, a full RTI period elapses before the first RTI interrupt.
5.2.6 Pulse Accumulator
The pulse accumulator system is disabled at reset so that the PAI input pin defaults to
being a general-purpose input pin (PA7).
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5.2.7 COP
The COP watchdog system is enabled if the NOCOP control bit in the CONFIG register is clear, and disabled if NOCOP is set. The COP rate is set for the shortest duration
time-out.
5.2.8 SCI
The reset condition of the SCI system is independent of the operating mode. At reset,
the SCI baud rate is indeterminate and must be established by a software write to the
BAUD register. All transmit and receive interrupts are masked and both the transmitter
and receiver are disabled so the port pins default to being general-purpose I/O lines.
The SCI frame format is initialized to an 8-bit character size. The send break and receiver wake-up functions are disabled. The TDRE and TC status bits in the SCI status
register are both set, indicating that there is no transmit data in either the transmit data
register or the transmit serial shift register. The RDRF, IDLE, OR, NF, and FE receiverelated status bits are cleared.
5.2.9 SPI
The SPI system is disabled by reset. The port pins associated with this function default
to being general-purpose I/O lines.
5.2.10 System
The memory system is configured for normal read operation. PSEL[3:0] are initialized
with the value $0101, causing the external IRQ pin to have the highest I-bit interrupt
priority. The IRQ pin is configured for level sensitive operation (for wired-OR systems).
The RBOOT, SMOD, and MDA bits in the HPRIO register reflect the status of the
MODB and MODA inputs at the rising edge of reset. The DLY control bit in OPTION is
set to specify that an oscillator start-up delay is imposed upon recovery from STOP.
The clock monitor system is disabled by CME equals zero.
5.3 Reset and Interrupt Priority
Resets and interrupts have a hardware priority that determines which reset or interrupt
is serviced first when simultaneous requests occur. Any maskable interrupt can be given priority over other maskable interrupts.
The first six interrupt sources are not maskable. The priority arrangement for these
sources is as follows:
1.
2.
3.
4.
5.
6.
POR or RESET pin
Clock monitor reset
COP watchdog reset
XIRQ interrupt
Illegal opcode interrupt
Software interrupt (SWI)
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The maskable interrupt sources have the following priority arrangement:
1. IRQ
2. Real-time interrupt
3. Timer input capture 1
4. Timer input capture 2
5. Timer input capture 3
6. Timer output compare 1
7. Timer output compare 2
8. Timer output compare 3
9. Timer output compare 4
10. Timer input capture 4/output compare 5
11. Timer overflow
12. Pulse accumulator overflow
13. Pulse accumulator input edge
14. SPI transfer complete
15. SCI system
Any one of these interrupts can be assigned the highest maskable interrupt priority by
writing the appropriate value to the PSEL bits in the HPRIO register. Otherwise, the
priority arrangement remains the same. An interrupt that is assigned highest priority is
still subject to global masking by the I bit in the CCR, or by any associated local bits.
Interrupt vectors are not affected by priority assignment. To avoid race conditions,
HPRIO can be written only while I-bit interrupts are inhibited.
5.3.1 Highest Priority Interrupt and Miscellaneous Register
HPRIO — Highest Priority I-Bit Interrupt and Miscellaneous
RESET:
Bit 7
RBOOT
—
6
SMOD
—
5
MDA
—
4
IRVNE
—
3
PSEL3
0
$003C
2
PSEL2
1
1
PSEL1
0
Bit 0
PSEL0
1
The values of the RBOOT, SMOD, IRVNE, and MDA reset bits depend on the mode
during initialization. Refer to Table 5-3.
RBOOT — Read Bootstrap ROM
Has meaning only when the SMOD bit is a one (special bootstrap mode or special test
mode). At all other times this bit is clear and cannot be written. Refer to SECTION 4
OPERATING MODES AND ON-CHIP MEMORY for more information.
SMOD — Special Mode Select
This bit reflects the inverse of the MODB input pin at the rising edge of reset. Refer to
SECTION 4 OPERATING MODES AND ON-CHIP MEMORY for more information.
MDA — Mode Select A
The mode select A bit reflects the status of the MODA input pin at the rising edge of
reset. Refer to SECTION 4 OPERATING MODES AND ON-CHIP MEMORY for more
information.
IRVNE — Internal Read Visibility Enable/Not E
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The IRVNE control bit allows internal read accesses to be available on the external
data bus during factory testing or emulation. Refer to SECTION 4 OPERATING
MODES AND ON-CHIP MEMORY for more information.
PSEL[3:0] — Priority Select Bits
These bits select one interrupt source to be elevated above all other I-bit-related
sources and can be written to only while the I bit in the CCR is set (interrupts disabled).
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Table 5-3 Highest Priority Interrupt Selection
PSEL[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Interrupt Source Promoted
Timer Overflow
Pulse Accumulator Overflow
Pulse Accumulator Input Edge
SPI Serial Transfer Complete
SCI Serial System
Reserved (Default to IRQ)
IRQ (External Pin)
Real-Time Interrupt
Timer Input Capture 1
Timer Input Capture 2
Timer Input Capture 3
Timer Output Compare 1
Timer Output Compare 2
Timer Output Compare 3
Timer Output Compare 4
Timer Input Capture 4/Output Compare 5
5.4 Interrupts
The MCU has 18 interrupt vectors that support 22 interrupt sources. The 19 maskable
interrupts are generated by on-chip peripheral systems. These interrupts are recognized when the global interrupt mask bit (I) in the condition code register (CCR) is
clear. The three non-maskable interrupt sources are illegal opcode trap, software interrupt, and XIRQ pin. Refer to Table 5-4, which shows the interrupt sources and vector assignments for each source.
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Table 5-4 Interrupt and Reset Vector Assignments
Vector Address
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FFC0, C1 — FFD4, D5
FFD6, D7
FFD8, D9
FFDA, DB
FFDC, DD
FFDE, DF
FFE0, E1
FFE2, E3
FFE4, E5
FFE6, E7
FFE8, E9
FFEA, EB
FFEC, ED
FFEE, EF
FFF0, F1
FFF2, F3
FFF4, F5
FFF6, F7
FFF8, F9
FFFA, FB
FFFC, FD
FFFE, FF
Interrupt Source
Reserved
SCI Serial System
• SCI Transmit Complete
• SCI Transmit Data Register Empty
• SCI Idle Line Detect
• SCI Receiver Overrun
• SCI Receive Data Register Full
SPI Serial Transfer Complete
Pulse Accumulator Input Edge
Pulse Accumulator Overflow
Timer Overflow
Timer Input Capture 4/Output Compare 5
Timer Output Compare 4
Timer Output Compare 3
Timer Output Compare 2
Timer Output Compare 1
Timer Input Capture 3
Timer Input Capture 2
Timer Input Capture 1
Real Time Interrupt
IRQ (External Pin)
XIRQ Pin
Software Interrupt
Illegal Opcode Trap
COP Failure
Clock Monitor Fail
RESET
CCR Mask
—
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
I Bit
X Bit
None
None
None
None
None
Local
Mask
—
—
TCIE
TIE
ILIE
RIE
RIE
SPIE
PAII
PAOVI
TOI
I4/O5I
OC4I
OC3I
OC2I
OC1I
IC3I
IC2I
IC1I
RTII
None
None
None
None
NOCOP
CME
None
5.4.1 Interrupt Recognition and Register Stacking
An interrupt can be recognized at any time after it is enabled by its local mask, if any,
and by the global mask bit in the CCR. Once an interrupt source is recognized, the
CPU responds at the completion of the instruction being executed. Interrupt latency
varies according to the number of cycles required to complete the current instruction.
When the CPU begins to service an interrupt, the contents of the CPU registers are
pushed onto the stack in the order shown in Table 5-5. After the CCR value is stacked,
the I bit and the X bit, if XIRQ is pending, are set to inhibit further interrupts. The interrupt vector for the highest priority pending source is fetched, and execution continues
at the address specified by the vector. At the end of the interrupt service routine, the
return from interrupt instruction is executed and the saved registers are pulled from the
stack in reverse order so that normal program execution can resume. Refer to SECTION 3 CENTRAL PROCESSING UNIT for further information.
RESETS AND INTERRUPTS
TECHNICAL DATA
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Table 5-5 Stacking Order on Entry to Interrupts
Freescale Semiconductor, Inc...
Memory Location
SP
SP – 1
SP –2
SP – 3
SP – 4
SP – 5
SP – 6
SP – 7
SP – 8
CPU Registers
PCL
PCH
IYL
IYH
IXL
IXH
ACCA
ACCB
CCR
5.4.2 Non-Maskable Interrupt Request XIRQ
Non-maskable interrupts are useful because they can always interrupt CPU operations. The most common use for such an interrupt is for serious system problems, such
as program runaway or power failure. The XIRQ input is an updated version of the
nonmaskable NMI input of earlier MCUs.
Upon reset, both the X bit and I bits of the CCR are set to inhibit all maskable interrupts
and XIRQ. After minimum system initialization, software can clear the X bit by a TAP
instruction, enabling XIRQ interrupts. Thereafter, software cannot set the X bit. Thus,
an XIRQ interrupt is a nonmaskable interrupt. Because the operation of the I-bit-related interrupt structure has no effect on the X bit, the internal XIRQ pin remains nonmasked. In the interrupt priority logic, the XIRQ interrupt has a higher priority than any
source that is maskable by the I bit. All I-bit-related interrupts operate normally with
their own priority relationship.
When an I-bit-related interrupt occurs, the I bit is automatically set by hardware after
stacking the CCR byte. The X bit is not affected. When an X-bit-related interrupt occurs, both the X and I bits are automatically set by hardware after stacking the CCR.
A return from interrupt instruction restores the X and I bits to their pre-interrupt request
state.
5.4.3 Illegal Opcode Trap
Because not all possible opcodes or opcode sequences are defined, the MCU includes an illegal opcode detection circuit, which generates an interrupt request. When
an illegal opcode is detected and the interrupt is recognized, the current value of the
program counter is stacked. After interrupt service is complete, reinitialize the stack
pointer so repeated execution of illegal opcodes does not cause stack underflow. Left
uninitialized, the illegal opcode vector can point to a memory location that contains an
illegal opcode. This condition causes an infinite loop that causes stack underflow. The
stack grows until the system crashes.
The illegal opcode trap mechanism works for all unimplemented opcodes on all four
opcode map pages. The address stacked as the return address for the illegal opcode
interrupt is the address of the first byte of the illegal opcode. Otherwise, it would be
almost impossible to determine whether the illegal opcode had been one or two bytes.
RESETS AND INTERRUPTS
5-10
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The stacked return address can be used as a pointer to the illegal opcode so the illegal
opcode service routine can evaluate the offending opcode.
Freescale Semiconductor, Inc...
5.4.4 Software Interrupt
SWI is an instruction, and thus cannot be interrupted until complete. SWI is not inhibited by the global mask bits in the CCR. Because execution of SWI sets the I mask bit,
once an SWI interrupt begins, other interrupts are inhibited until SWI is complete, or
until user software clears the I bit in the CCR.
5.4.5 Maskable Interrupts
The maskable interrupt structure of the MCU can be extended to include additional external interrupt sources through the IRQ pin. The default configuration of this pin is a
low-level sensitive wired-OR network. When an event triggers an interrupt, a software
accessible interrupt flag is set. When enabled, this flag causes a constant request for
interrupt service. After the flag is cleared, the service request is released.
5.4.6 Reset and Interrupt Processing
Figure 5-1 and Figure 5-1 illustrate the reset and interrupt process. Figure 5-1 illustrates how the CPU begins from a reset and how interrupt detection relates to normal
opcode fetches. Figure 5-1 is an expansion of a block in Figure 5-1 and illustrates interrupt priorities. Figure 5-2 shows the resolution of interrupt sources within the SCI
subsystem.
RESETS AND INTERRUPTS
TECHNICAL DATA
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HIGHEST
PRIORITY
POWER-ON RESET
(POR)
DELAY 4064 E CYCLES
EXTERNAL RESET
CLOCK MONITOR FAIL
(WITH CME = 1)
Freescale Semiconductor, Inc...
LOWEST
PRIORITY
COP WATCHDOG
TIMEOUT
(WITH NOCOP = 0)
LOAD PROGRAM COUNTER
WITH CONTENTS OF
$FFFE, $FFFF
(VECTOR FETCH)
LOAD PROGRAM COUNTER
WITH CONTENTS OF
$FFFC, $FFFD
(VECTOR FETCH)
LOAD PROGRAM COUNTER
WITH CONTENTS OF
$FFFA, $FFFB
(VECTOR FETCH)
SET BITS S, I, AND X
RESET MCU
HARDWARE
1A
BEGIN INSTRUCTION
SEQUENCE
Y
BIT X IN
CCR = 1?
N
XIRQ
PIN LOW?
Y
N
2A
STACK CPU
REGISTERS
SET BITS I AND X
FETCH VECTOR
$FFF4, $FFF5
FLOW OUT OF RESET P1
Figure 5-1 Processing Flow out of Reset (1 of 2)
RESETS AND INTERRUPTS
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2A
Y
BIT I IN
CCR = 1?
N
ANY I-BIT
INTERRUPT
PENDING?
Y
STACK CPU
REGISTERS
N
Freescale Semiconductor, Inc...
FETCH OPCODE
Y
STACK CPU
REGISTERS
ILLEGAL
OPCODE?
SET BIT I IN CCR
N
FETCH VECTOR
$FFF8, $FFF9
WAI
Y
INSTRUCTION?
STACK CPU
REGISTERS
N
Y
STACK CPU
REGISTERS
SWI
INSTRUCTION?
N
N
SET BIT I IN CCR
FETCH VECTOR
$FFF6, $FFF7
Y
RESTORE CPU
REGISTERS
FROM STACK
Y
SET BIT I IN CCR
RTI
INSTRUCTION?
N
EXECUTE THIS
INSTRUCTION
ANY
INTERRUPT
PENDING?
RESOLVE INTERRUPT
PRIORITY AND FETCH
VECTOR FOR HIGHEST
PENDING SOURCE
SEE FIGURE 5–2
1A
FLOW OUT OF RESET P2
Figure 5-1 Processing Flow out of Reset (2 of 2)
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BEGIN
X BIT
IN CCR
SET ?
YES
NO
HIGHEST
PRIORITY
INTERRUPT
?
NO
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IRQ ?
XIRQ PIN
LOW ?
YES
SET X BIT IN CCR
FETCH VECTOR
$FFF4, FFF5
NO
YES
FETCH VECTOR
YES
FETCH VECTOR
$FFF2, FFF3
NO
RTII = 1 ?
YES
NO
YES
NO
FETCH VECTOR
$FFF0, FFF1
TIMER
IC1F ?
YES
FETCH VECTOR
$FFEE, FFEF
YES
FETCH VECTOR
$FFEC, FFED
YES
FETCH VECTOR
$FFEA, FFEB
YES
FETCH VECTOR
$FFE8, FFE9
NO
YES
IC2I = 1 ?
NO
TIMER
IC2F ?
NO
YES
IC3I = 1 ?
NO
TIMER
IC3F ?
NO
YES
NO
YES
NO
IC1I = 1 ?
OC1I = 1 ?
REAL-TIME
INTERRUPT
?
TIMER
OC1F ?
NO
2A
2B
INT PRIORITY RES P1
Figure 5-2 Interrupt Priority Resolution (1 of 2)
RESETS AND INTERRUPTS
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2A
2B
Y
OC2I = 1?
Y
OC3I = 1?
Y
OC4I = 1?
Freescale Semiconductor, Inc...
FETCH VECTOR
$FFE6, $FFE7
FLAG
OC3F = 1
Y
FETCH VECTOR
$FFE4, $FFE5
Y
FETCH VECTOR
$FFE2, $FFE3
Y
FETCH VECTOR
$FFE0, $FFE1
Y
FETCH VECTOR
$FFDE, $FFDF
Y
FETCH VECTOR
$FFDC, $FFDD
Y
FETCH VECTOR
$FFDA, $FFDB
Y
FETCH VECTOR
$FFD8, $FFD9
N
N
FLAG
OC4F = 1?
N
N
Y
OC5I = 1?
FLAG
OC5F = 1?
N
N
Y
TOI = 1?
FLAG
TOF = 1?
N
N
Y
PAOVI = 1?
FLAG
PAOVF = 1
N
N
Y
PAII = 1?
FLAG
PAIF = 1?
N
N
Y
SPIE = 1?
FLAGS
SPIF = 1? OR
MODF = 1?
N
N
N
Y
N
N
SCI
INTERRUPT?
SEE FIGURE
9–7
FLAG
OC2F = 1?
Y
FETCH VECTOR
$FFD6, $FFD7
FETCH VECTOR
$FFF2, $FFF3
END
INT PRI RES P2
Figure 5-2 Interrupt Priority Resolution (2 of 2)
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BEGIN
FLAG
RDRF = 1?
Y
N
OR = 1?
Y
RIE = 1?
N
N
Y
Freescale Semiconductor, Inc...
Y
TDRE = 1?
Y
N
Y
Y
TE = 1?
TIE = 1?
N
N
RE = 1?
N
Y
Y
TCIE = 1?
TC = 1?
N
N
Y
IDLE = 1?
Y
ILIE = 1?
N
N
Y
RE = 1?
N
NO
VALID SCI REQUEST
VALID SCI REQUEST
INT SOURCE RES
Figure 5-3 Interrupt Source Resolution within SCI
5.5 Low-Power Operation
Both STOP and WAIT suspend CPU operation until a reset or interrupt occurs. The
WAIT condition suspends processing and reduces power consumption to an intermediate level. The STOP condition turns off all on-chip clocks and reduces power consumption to an absolute minimum while retaining the contents of all 192 bytes of RAM.
5.5.1 WAIT
The WAI opcode places the MCU in the WAIT condition, during which the CPU registers are stacked and CPU processing is suspended until a qualified interrupt is detected. The interrupt can be an external IRQ, an XIRQ, or any of the internally generated
interrupts, such as the timer or serial interrupts. The on-chip crystal oscillator remains
active throughout the WAIT standby period.
The reduction of power in the WAIT condition depends on how many internal clock sigRESETS AND INTERRUPTS
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nals driving on-chip peripheral functions can be shut down. The CPU is always shut
down during WAIT. While in the wait state, the address/data bus repeatedly runs read
cycles to the address where the CCR contents were stacked. The MPU leaves the wait
state when it senses any interrupt that has not been masked.
Freescale Semiconductor, Inc...
The free-running timer system is shut down only if the I bit is set to one and the COP
system is disabled by NOCOP being set to one. Several other systems can also be in
a reduced power consumption state depending on the state of software-controlled
configuration control bits. The SPI system is enabled or disabled by the SPE control
bit. The SCI transmitter is enabled or disabled by the TE bit, and the SCI receiver is
enabled or disabled by the RE bit. Therefore the power consumption in WAIT is dependent on the particular application.
5.5.2 STOP
Executing the STOP instruction while the S bit in the CCR is equal to zero places the
MCU in the STOP condition. If the S bit is not zero, the STOP opcode is treated as a
no-op (NOP). The STOP condition offers minimum power consumption because all
clocks, including the crystal oscillator, are stopped while in this mode. To exit STOP
and resume normal processing, a logic low level must be applied to one of the external
interrupts (IRQ or XIRQ), or to the RESET pin. A pending edge-triggered IRQ can also
bring the CPU out of STOP.
Because all clocks are stopped in this mode, all internal peripheral functions also stop.
The data in the internal RAM is retained as long as VDD power is maintained. The CPU
state and I/O pin levels are static and are unchanged by STOP. Therefore, when an
interrupt comes to restart the system, the MCU resumes processing as if there were
no interruption. If reset is used to restart the system a normal reset sequence results
where all I/O pins and functions are also restored to their initial states.
To use the IRQ pin as a means of recovering from STOP, the I bit in the CCR must be
clear (IRQ not masked). The XIRQ pin can be used to wake up the MCU from STOP
regardless of the state of the X bit in the CCR, although the recovery sequence depends on the state of the X bit. If X is set to zero (XIRQ not masked), the MCU starts
up, beginning with the stacking sequence leading to normal service of the XIRQ request. If X is set to one (XIRQ masked or inhibited), then processing continues with
the instruction that immediately follows the STOP instruction, and no XIRQ interrupt
service is requested or pending.
Because the oscillator is stopped in STOP mode, a restart delay may be imposed to
allow oscillator stabilization upon leaving STOP. If the internal oscillator is being used,
this delay is required; however, if a stable external oscillator is being used, the DLY
control bit can be used to bypass this startup delay. The DLY control bit is set by reset
and can be optionally cleared during initialization. If the DLY equal to zero option is
used to avoid startup delay on recovery from STOP, then reset should not be used as
the means of recovering from STOP, as this causes DLY to be set again by reset, imposing the restart delay. This same delay also applies to power-on-reset, regardless
of the state of the DLY control bit, but does not apply to a reset while the clocks are
running.
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5-18
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SECTION 6
PARALLEL I/O
The MC68HC11D3 has four 8-bit I/O ports; A, B, C, and D. In single-chip and bootstrap
modes, all ports are parallel I/O data ports. In expanded multiplexed and test modes,
ports B and C, and lines DATA6/AS and DATA7/R/W are a memory expansion bus
with port B as the high order address bus, port C as the multiplexed address and data
bus, AS as the demultiplexing signal, and R/W as the data bus direction control. Refer
to Table 6-1, which is a summary of the ports and their shared functions:
Freescale Semiconductor, Inc...
Table 6-1 I/O Ports
Port
Port A
Port B
Port C
Port D
Input Pins
3
—
—
—
Output Pins
3
—
—
—
Bidirectional Pins
2
8
8
8
Shared Functions
TImer
High Order Address
Low Order Address and Data Bus
SCI, SPI, AS, and R/
6.1 Port A
Port A bits handle the timer functions and can also be used as general-purpose I/O. In
both the normal operating modes, port A can be configured for four timer input capture
(IC) and three timer output compare (OC) functions, or four OC and three IC functions
with either a pulse accumulator input (PAI) or a fifth OC function.
PORTA — Port A Data
RESET:
Alt. Func:
And/or:
$0000
Bit 7
PA7
HiZ
6
PA6*
0
5
PA5
0
4
PA4*
0
3
PA3
HiZ
2
PA2
HiZ
1
PA1
HiZ
Bit 0
PA0
HiZ
PAI
OC1
OC2
OC1
OC3
OC1
OC4
OC1
IC4/OC5
OC1
IC1
—
IC2
—
IC3
—
*This pin is not bonded in the 40-pin version.
6.2 Port B
In single-chip mode, all port B pins are general-purpose I/O (PB[7:0]). In expanded
multiplexed mode, all port B pins act as high-order address bits (ADDR[15:8]).
PORTB — Port B Data
S. Chip
or Boot:
RESET:
Expan.
or Test:
RESET:
$0004
Bit 7
PB7
6
PB6
5
PB5
4
PB4
3
PB3
2
PB2
1
PB1
Bit 0
PB0
PB7
PB6
PB5
PB4
PB3
PB2
Reset configures pins as HiZ inputs
PB1
PB0
ADDR15
ADDR14
ADDR13
ADDR12
ADDR11
ADDR10
Reset configures pins as high-order address outputs
ADDR9
ADDR8
PARALLEL I/O
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DDRB — Data Direction Register for Port B
RESET:
Bit 7
DDB7
0
6
DDB6
0
5
DDB5
0
4
DDC4
0
$0006
3
DDB3
0
2
DDB2
0
1
DDB1
0
Bit 0
DDB0
0
DDB[7:0] — Data Direction for Port B
0 = Corresponding port B pin configured for input only
1 = Corresponding port B pin configured as output
Freescale Semiconductor, Inc...
6.3 Port C
Port C pins are general-purpose I/O (PC[7:0]) in single-chip mode. In expanded multiplexed mode, port C pins are configured as multiplexed address/data pins. During the
data cycle, bits [7:0] (PC[7:0]) are bidirectional data pins controlled by the R/W signal.
PORTC — Port C Data
S. Chip
or Boot:
RESET:
Expan.
or Test:
RESET:
$0003
Bit 7
PC7
6
PC6
PC7
PC6
ADDR7/
DATA7
5
PC5
4
PC4
3
PC3
2
PC2
1
PC1
PC5
PC4
PC3
PC2
PC1
Reset configures pins as HiZ inputs
ADDR6/
ADDR5/
ADDR4/
ADDR3/
ADDR2/
ADDR1/
DATA6
DATA5
DATA4
DATA3
DATA2
DATA1
Reset configures pins as multiplexed, low-order address/data I/O
DDRC — Data Direction Register for Port C
RESET:
Bit 7
DDC7
0
6
DDC6
0
5
DDC5
0
4
DDC4
0
Bit 0
PC0
PC0
ADDR0/
DATA0
$0007
3
DDC3
0
2
DDC2
0
1
DDC1
0
Bit 0
DDC0
0
DDC[7:0] — Data Direction for Port C
0 = Input
1 = Output
6.4 Port D
The eight port D bits (PD[7:0]) can be used for general-purpose I/O, for the SCI and
SPI subsystems, or for bus data direction control. Port D can be read at any time. Inputs return the sensed levels at the pin; outputs return the input level of the port D pin
drivers. If port D is written, the data is stored in an internal latch, and can be driven only
if port D is configured for general-purpose output. This port shares functions with the
on-chip SCI and SPI subsystems, while bits 6 and 7 control the direction of data flow
on the bus in expanded and special test modes.
PARALLEL I/O
6-2
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PORTD — Port D Data
RESET:
Alt. Func.:
Bit 7
PD7
0
R/W
$0008
6
PD6
0
AS
5
PD5
0
4
PD4
0
SCK
3
PD3
0
MOSI
2
PD2
0
MISO
1
PD1
0
TxD
DDRD — Data Direction Register for Port D
Freescale Semiconductor, Inc...
RESET:
Bit 7
DDD7
0
6
DDD6
0
5
DDD5
0
4
DDD4
0
Bit 0
PD0
0
RxD
$0009
3
DDD3
0
2
DDD2
0
1
DDD1
0
Bit 0
DDD0
0
DDD[7:0] — Data Direction for Port D
When port D is a general-purpose I/O port, the DDRD register controls the direction of
the I/O pins as follows:
0 = Configures the corresponding port D pin for input
1 = Configures the corresponding port D pin for output
In expanded and test modes, bits 6 and 7 are dedicated AS and R/W outputs.
When port D is functioning with the SPI system enabled, bit 5 is dedicated as the slave
select (SS) input. In SPI slave mode, DDD5 has no meaning or effect. In SPI master
mode, DDD5 affects port D bit 5 as follows:
0 = Port D bit 5 is an error-detect input to the SPI.
1 = Port D bit 5 is configured as a general-purpose output line.
If the SPI is enabled and expects port D bits 2, 3, and 4 (MISO, MOSI, and SCK) to be
inputs, then they are inputs, regardless of the state of DDRD bits 2, 3, and 4. If the SPI
expects port D bits 2, 3, and 4 to be outputs, they are outputs only if DDRD bits 2, 3,
and 4 are set.
PACTL — Pulse Accumulator Control
RESET:
Bit 7
DDRA7
0
6
PAEN
0
5
PAMOD
0
$0026
4
PEDGE
0
3
DDRA3
0
2
I4/O5
0
1
RTR1
0
Bit 0
RTR0
0
DDRA7 — Data Direction Control for Port A Bit 7
Refer to SECTION 9 TIMING SYSTEM.
PAEN — Pulse Accumulator System Enable
Refer to SECTION 9 TIMING SYSTEM.
PAMOD — Pulse Accumulator Mode
Refer to SECTION 9 TIMING SYSTEM.
PEDGE — Pulse Accumulator Edge Control
Refer to SECTION 9 TIMING SYSTEM.
DDRA3 — Data Direction for Port A Bit 3
Overridden if an output compare function is configured to control the PA3 pin.
0 = Input only
1 = Output
PARALLEL I/O
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I4/O5 — Configure TI4/O5 register for IC4 or OC5
0 = OC5 function enabled
1 = IC4 function enabled
RTR[1:0] — Real-Time Interrupt (RTI) Rate
Refer to SECTION 9 TIMING SYSTEM.
6.5 Parallel I/O Control Register (PIOC)
PIOC configures and controls handshake I/O functions in MCUs where this function is
available. In the MC68HC11D3, however, only the CWOM bit in the PIOC register is
usable. The CWOM bit is cleared so that port C is not in wired-OR mode.
Freescale Semiconductor, Inc...
PIOC— Parallel I/O Control
RESET:
Bit 7
0
0
6
0
0
$0002
5
CWOM
0
4
0
0
3
0
0
2
0
0
1
0
0
Bit 0
0
0
CWOM — Port C Wired-OR Mode (affects all eight port C pins)
0 = Port C outputs are normal CMOS outputs
1 = Port C outputs are open-drain outputs
PARALLEL I/O
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SECTION 7
SERIAL COMMUNICATIONS INTERFACE
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The serial communications interface (SCI) is a universal asynchronous receiver transmitter (UART), one of two independent serial I/O subsystems in the MC68HC11D3. It
has a standard nonreturn to zero (NRZ) format (one start, eight or nine data, and one
stop bit). Several baud rates are available. The SCI transmitter and receiver are independent, but use the same data format and bit rate.
7.1 Data Format
The serial data format requires the following conditions:
1. An idle line in the high state before transmission or reception of a message
2. A start bit, logic zero, transmitted or received, that indicates the start of each
character
3. Data that is transmitted and received least significant bit (LSB) first
4. A stop bit, logic one, used to indicate the end of a frame (A frame consists of a
start bit, a character of eight or nine data bits, and a stop bit.)
5. A break (defined as the transmission or reception of a logic zero for some multiple number of frames).
Selection of the word length is controlled by the M bit of SCI control register SCCR1.
7.2 Transmit Operation
The SCI transmitter includes a parallel transmit data register (SCDR) and a serial shift
register. The contents of the serial shift register can only be written through the SCDR.
This double buffered operation allows a character to be shifted out serially while another character is waiting in the SCDR to be transferred into the serial shift register.
The output of the serial shift register is applied to TxD as long as transmission is in
progress or the transmit enable (TE) bit of serial communication control register 2
(SCCR2) is set. The block diagram, Figure 7-1, shows the transmit serial shift register,
and the buffer logic at the top of the figure.
SERIAL COMMUNICATIONS INTERFACE
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TRANSMITTER
BAUD RATE
CLOCK
(WRITE ONLY)
SCDR Tx BUFFER
DDD1
10 (11) - BIT Tx SHIFT REGISTER
2
1
0
PIN BUFFER
AND CONTROL
L
BREAK—JAM 0s
3
JAM ENABLE
4
PREAMBLE—JAM 1s
5
SHIFT ENABLE
SIZE 8/9
Freescale Semiconductor, Inc...
6
TRANSFER Tx BUFFER
H (8) 7
PD1
TxD
8
FORCE PIN
DIRECTION (OUT)
TRANSMITTER
CONTROL LOGIC
SCCR1 SCI CONTROL 1
FE
NF
OR
IDLE
RDRF
TC
TDRE
WAKE
M
T8
R8
8
SCSR INTERRUPT STATUS
8
TDRE
TIE
TC
SBK
RWU
RE
TE
ILIE
RIE
TCIE
TIE
TCIE
SCCR2 SCI CONTROL 2
SCI Rx
REQUESTS
SCI INTERRUPT
REQUEST
INTERNAL
DATA BUS
11 SCI TX BLOCK
Figure 7-1 SCI Transmitter Block Diagram
7.3 Receive Operation
During receive operations, the transmit sequence is reversed. The serial shift register
receives data and transfers it to a parallel receive data register (SCDR) as a complete
word. Refer to Figure 7-2. This double buffered operation allows a character to be
shifted in serially while another character is already in the SCDR. An advanced data
SERIAL COMMUNICATIONS INTERFACE
7-2
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recovery scheme distinguishes valid data from noise in the serial data stream. The
data input is selectively sampled to detect receive data, and a majority voting circuit
determines the value and integrity of each bit.
RECEIVER
BAUD RATE
CLOCK
10 (11) - BIT
Rx SHIFT REGISTER
DATA
RECOVERY
PIN BUFFER
AND CONTROL
PD0
RxD
STOP
÷16
(8) 7
6
5
4
3
2
1
0
MSB
DISABLE
DRIVER
ALL ONES
RE
M
WAKEUP
LOGIC
RWU
FE
NF
OR
IDLE
RDRF
TC
TDRE
WAKE
M
T8
8
R8
SCSR SCI STATUS 1
SCCR1 SCI CONTROL 1
SCDR Rx BUFFER
(READ ONLY)
8
RDRF
RIE
IDLE
ILIE
OR
SBK
RWU
RE
TE
ILIE
RIE
TCIE
RIE
TIE
Freescale Semiconductor, Inc...
START
DDD0
8
SCCR2 SCI CONTROL 2
SCI Tx
REQUESTS
SCI INTERRUPT
REQUEST
INTERNAL
DATA BUS
11 SCI RX BLOCK
Figure 7-2 SCI Receiver Block Diagram
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Freescale Semiconductor, Inc...
7.4 Wake-up Feature
The wake-up feature reduces SCI service overhead in multiple receiver systems. Software for each receiver evaluates the first character of each message. The receiver is
placed in wakeup mode by writing a one to the RWU bit in the SCCR2 register. While
RWU is one, all of the receiver-related status flags (RDRF, IDLE, OR, NF, and FE) are
inhibited (cannot become set). Although RWU can be cleared by a software write to
SCCR2, to do so would be unusual. Normally RWU is set by software and is cleared
automatically with hardware. Whenever a new message begins, logic alerts the sleeping receivers to wake up and evaluate the initial character of the new message.
Two methods of wake-up are available: idle line wake-up and address mark wake-up.
During idle line wake-up, a sleeping receiver awakens as soon as the RxD line becomes idle. In the address mark wake-up, logic one in the most significant bit (MSB)
of a character wakes up all sleeping receivers.
7.4.1 Idle-Line Wakeup
To use the receiver wake-up method, establish a software addressing scheme to allow
the transmitting devices to direct a message to individual receivers or to groups of receivers. This addressing scheme can take any form as long as all transmitting and receiving devices are programmed to understand the same scheme. Because the
addressing information is usually the first frame(s) in a message, receivers that are not
part of the current task do not become burdened with the entire set of addressing
frames. All receivers are awake (RWU = 0) when each message begins. As soon as
a receiver determines that the message is not intended for it, software sets the RWU
bit (RWU = 1), which inhibits further flag setting until the RxD line goes idle at the end
of the message. As soon as an idle line is detected by receiver logic, hardware automatically clears the RWU bit so that the first frame of the next message can be received. This type of receiver wakeup requires a minimum of one idle-line frame time
between messages, and no idle time between frames in a message.
7.4.2 Address-Mark Wakeup
The serial characters in this type of wakeup consist of seven (eight if M = 1) information
bits and an MSB, which indicates an address character (when set to one — mark). The
first character of each message is an addressing character (MSB = 1). All receivers in
the system evaluate this character to determine if the remainder of the message is directed toward this particular receiver. As soon as a receiver determines that a message is not intended for it, the receiver activates the RWU function by using a software
write to set the RWU bit. Because setting RWU inhibits receiver-related flags, there is
no further software overhead for the rest of this message. When the next message begins, its first character has its MSB set, which automatically clears the RWU bit and
enables normal character reception. The first character whose MSB is set is also the
first character to be received after wakeup because RWU gets cleared before the stop
bit for that frame is serially received. This type of wakeup allows messages to include
gaps of idle time, unlike the idle-line method, but there is a loss of efficiency because
of the extra bit time for each character (address bit) required for all characters.
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7.5 SCI Error Detection
Three error conditions, SCDR overrun, received bit noise, and framing can occur during generation of SCI system interrupts. Three bits (OR, NF, and FE) in the serial communications status register (SCSR) indicate if one of these error conditions exists. The
overrun error (OR) bit is set when the next byte is ready to be transferred from the receive shift register to the SCDR and the SCDR is already full (RDRF bit is set). When
an overrun error occurs, the data that caused the overrun is lost and the data that was
already in SCDR is not disturbed. The OR is cleared when the SCSR is read (with OR
set), followed by a read of the SCDR.
Freescale Semiconductor, Inc...
The noise flag (NF) bit is set if there is noise on any of the received bits, including the
start and stop bits. The NF bit is not set until the RDRF flag is set. The NF bit is cleared
when the SCSR is read (with FE equal to one) followed by a read of the SCDR.
When no stop bit is detected in the received data character, the framing error (FE) bit
is set. FE is set at the same time as the RDRF. If the byte received causes both framing and overrun errors, the processor only recognizes the overrun error. The framing
error flag inhibits further transfer of data into the SCDR until it is cleared. The FE bit is
cleared when the SCSR is read (with FE equal to one) followed by a read of the SCDR.
7.6 SCI Registers
There are five addressable registers in the SCI.
7.6.1 Serial Communications Data Register (SCDR)
SCDR is a parallel register that performs two functions. It is the receive data register
when it is read, and the transmit data register when it is written. Reads access the receive data buffer and writes access the transmit data buffer. Receive and transmit are
double buffered.
SCDR — SCI Data Register
RESET:
Bit 7
R7/T7
U*
6
R6/T6
U
$002F
5
R5/T5
U
4
R4/T4
U
3
R3/T3
U
2
R2/T2
U
1
R1/T1
U
Bit 0
R0/T0
U
*U = Unaffected
7.6.2 Serial Communications Control Register 1 (SCCR1)
The SCCR1 register provides the control bits that determine word length and select
the method used for the wake-up feature.
SCCR1 — SCI Control Register 1
RESET:
Bit 7
R8
U
6
T8
U
5
0
0
$002C
4
M
0
3
WAKE
0
2
0
0
1
0
0
Bit 0
0
0
R8 — Receive Data Bit 8
If M bit is set, R8 stores the ninth bit in the receive data character.
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T8 — Transmit Data bit 8
If M bit is set, T8 stores ninth bit in transmit data character.
M — Mode (Select Character Format)
0 = Start bit, 8 data bits, 1 stop bit
1 = Start bit, 9 data bits, 1 stop bit
WAKE — Wake-up by Address Mark/Idle
0 = Wake-up by IDLE line recognition
1 = Wake-up by address mark (most significant data bit set)
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7.6.3 Serial Communications Control Register 2 (SCCR2)
The SCCR2 register provides the control bits that enable or disable individual SCI
functions.
SCCR2 — SCI Control Register 2
RESET:
Bit 7
TIE
0
6
TCIE
0
5
RIE
0
$002D
4
ILIE
0
3
TE
0
2
RE
0
1
RWU
0
Bit 0
SBK
0
TIE — Transmit Interrupt Enable
0 = TDRE interrupts disabled
1 = SCI interrupt requested when TDRE status flag is set
TCIE — Transmit Complete Interrupt Enable
0 = TC interrupts disabled
1 = SCI interrupt requested when TC status flag is set
RIE — Receiver Interrupt Enable
0 = RDRF and OR interrupts disabled
1 = SCI interrupt requested when RDRF flag or the OR status flag is set
ILIE — Idle Line Interrupt Enable
0 = IDLE interrupts disabled
1 = SCI interrupt requested when IDLE status flag is set
TE — Transmitter Enable
When TE goes from zero to one, one unit of idle character time (logic one) is queued
as a preamble.
0 = Transmitter disabled
1 = Transmitter enabled
RE — Receiver Enable
0 = Receiver disabled
1 = Receiver enabled
RWU — Receiver Wake-Up Control
0 = Normal SCI receiver
1 = Wake-up enabled and receiver interrupts inhibited
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SBK — Send Break
At least one character time of break is queued and sent each time SBK is written to
one. More than one break may be sent if the transmitter is idle at the time the SBK bit
is toggled on and off, as the baud rate clock edge could occur between writing the one
and writing the zero to SBK.
0 = Break generator off
1 = Break codes generated as long as SBK = 1
7.6.4 Serial Communication Status Register (SCSR)
The SCSR provides inputs to the interrupt logic circuits for generation of the SCI system interrupt.
Freescale Semiconductor, Inc...
SCSR — SCI Status Register
RESET:
Bit 7
TDRE
1
6
TC
1
$002E
5
RDRF
0
4
IDLE
0
3
OR
0
2
NF
0
1
FE
0
Bit 0
0
0
TDRE — Transmit Data Register Empty Flag
This flag is set when SCDR is empty. Clear the TDRE flag by reading SCSR with
TDRE set and then writing to SCDR.
0 = SCDR busy
1 = SCDR empty
TC — Transmit Complete Flag
This flag is set when the transmitter is idle (no data, preamble, or break transmission
in progress). Clear the TC flag by reading SCSR with TC set and then writing to SCDR.
0 = Transmitter busy
1 = Transmitter idle
RDRF — Receive Data Register Full Flag
This flag is set if a received character is ready to be read from SCDR. Clear the RDRF
flag by reading SCSR with RDRF set and then reading SCDR.
0 = SCDR empty
1 = SCDR full
IDLE — Idle Line Detected Flag
This flag is set if the RxD line is idle. Once cleared, IDLE is not set again until the RxD
line has been active and becomes idle again. The IDLE flag is inhibited when RWU =
1. Clear IDLE by reading SCSR with IDLE set and then reading SCDR.
0 = RxD line is active
1 = RxD line is idle
OR — Overrun Error Flag
OR is set if a new character is received before a previously received character is read
from SCDR. Clear the OR flag by reading SCSR with OR set and then reading SCDR.
0 = No overrun
1 = Overrun detected
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NF — Noise Error Flag
NF is set if majority sample logic detects anything other than a unanimous decision.
Clear NF by reading SCSR with NF set and then reading SCDR.
0 = Unanimous decision
1 = Noise detected
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FE — Framing Error
FE is set when a 0 is detected where a stop bit was expected. Clear the FE flag by
reading SCSR with FE set and then reading SCDR.
0 = Stop bit detected
1 = 0 detected
7.6.5 Baud Rate Register (BAUD)
Use this register to select different baud rates for the SCI system. The SCP[1:0] bits
function as a prescaler for the SCR[2:0] bits. Together, these five bits provide multiple
baud rate combinations for a given crystal frequency. Normally, this register is written
once during initialization. The prescaler is set to its fastest rate by default out of reset,
and can be changed at any time. Refer to Table 7-1 and Table 7-2 for normal baud
rate selections.
BAUD — Baud Rate
RESET:
Bit 7
TCLR
0
$002B
6
0
0
5
SCP1
0
4
SCP0
0
3
RCKB
0
2
SCR2
U
1
SCR1
U
Bit 0
SCR0
U
TCLR — Clear Baud Rate Counters (Test)
RCKB — SCI Baud Rate Clock Check (Test)
SCP1, SCP0 — SCI Baud Rate Prescaler Selects
These two bits select a prescale factor for the SCI baud rate generator that determines
the highest possible baud rate.
Table 7-1 Baud Rate Prescale Selects
SCP[1:0]
00
01
10
11
Divide
Internal Clock
By
1
3
4
13
Crystal Frequency in MHz
4.0 MHz 8.0 MHz 10.0 MHz 12.0 MHz
(Baud)
(Baud)
(Baud)
(Baud)
62.50 K
125.0 K 156.25 K 187.5 K
20.83 K
41.67 K
52.08 K
62.5 K
15.625 K 31.25 K
38.4 K
46.88 K
4800
9600
12.02 K
14.42 K
SCR[2:0] — SCI Baud Rate Selects
These three bits select receiver and transmitter bit rate based on output from baud rate
prescaler stage.
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Table 7-2 Baud Rate Selects
SCR[2:0]
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000
001
010
011
100
101
110
111
Divide
Prescaler
By
1
2
4
8
16
32
64
128
Highest Baud Rate
(Prescaler Output from Previous Table)
4800
9600
38.4 K
4800
9600
38.4 K
2400
4800
19.2 K
1200
2400
9600
600
1200
4800
300
600
2400
150
300
1200
—
150
600
—
—
300
The prescale bits, SCP[1:0], determine the highest baud rate and the SCR[2:0] bits select an additional binary submultiple (≥1, ≥2, ≥4, through ≥128) of this highest baud
rate. The result of these two dividers in series is the 16 X receiver baud rate clock. The
SCR[2:0] bits are not affected by reset and can be changed at any time, although they
should not be changed when any SCI transfer is in progress.
Figure 7-3 illustrates the SCI baud rate timing chain. The prescale select bits determine the highest baud rate. The rate select bits determine additional divide by two
stages to arrive at the receiver timing (RT) clock rate. The baud rate clock is the result
of dividing the RT clock by 16.
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EXTAL
XTAL
INTERNAL BUS CLOCK (PH2)
OSCILLATOR
AND
CLOCK GENERATOR
÷3
(÷ 4)
÷4
÷ 13
SCP[1:0]
0:0
E
0:1
1:0
1:1
AS
Freescale Semiconductor, Inc...
SCR[2:0]
0:0:0
÷2
0:0:1
÷2
0:1:0
÷2
0:1:1
÷ 16
÷2
1:0:0
÷2
1:0:1
÷2
1:1:0
÷2
1:1:1
SCI
TRANSMIT
BAUD RATE
(1X)
SCI
RECEIVE
BAUD RATE
(16X)
SCI BAUD GENERATOR
Figure 7-3 SCI Baud Rate Diagram
7.7 Status Flags and Interrupts
The SCI transmitter has two status flags. These status flags can be read by software
(polled) to tell when the corresponding condition exists. Alternatively, a local interrupt
enable bit can be set to enable each of these status conditions to generate interrupt
requests when the corresponding condition is present. Status flags are automatically
set by hardware logic conditions, but must be cleared by software, which provides an
interlock mechanism that enables logic to know when software has noticed the status
indication. The software clearing sequence for these flags is automatic — functions
that are normally performed in response to the status flags also satisfy the conditions
of the clearing sequence.
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TDRE and TC flags are normally set when the transmitter is first enabled (TE set to
one). The TDRE flag indicates there is room in the transmit queue to store another
data character in the TDR. The TIE bit is the local interrupt mask for TDRE. When TIE
is zero, TDRE must be polled. When TIE and TDRE are one, an interrupt is requested.
Freescale Semiconductor, Inc...
The TC flag indicates the transmitter has completed the queue. The TCIE bit is the local interrupt mask for TC. When TCIE is zero, TC must be polled; when TCIE is one
and TC is one, an interrupt is requested.
Writing a zero to TE requests that the transmitter stop when it can. The transmitter
completes any transmission in progress before actually shutting down. Only an MCU
reset can cause the transmitter to stop and shut down immediately. If TE is written to
zero when the transmitter is already idle, the pin reverts to its general-purpose I/O
function (synchronized to the bit-rate clock). If anything is being transmitted when TE
is written to zero, that character is completed before the pin reverts to general-purpose
I/O, but any other characters waiting in the transmit queue are lost. The TC and TDRE
flags are set at the completion of this last character, even though TE has been disabled.
The SCI receiver has five status flags, three of which can generate interrupt requests.
The status flags are set by the SCI logic in response to specific conditions in the receiver. These flags can be read (polled) at any time by software. Refer to Figure 7-4,
which shows SCI interrupt arbitration.
When an overrun takes place, the new character is lost, and the character that was in
its way in the parallel RDR is undisturbed. RDRF is set when a character has been
received and transferred into the parallel RDR. The OR flag is set instead of RDRF if
overrun occurs. A new character is ready to be transferred into RDR before a previous
character is read from RDR.
The NF and FE flags provide additional information about the character in the RDR,
but do not generate interrupt requests.
The last receiver status flag and interrupt source come from the IDLE flag. The RxD
line is idle if it has constantly been at logic one for a full character time. The IDLE flag
is set only after the RxD line has been busy and becomes idle, which prevents repeated interrupts for the whole time RxD remains idle.
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BEGIN
FLAG
RDRF = 1?
Y
N
OR = 1?
Y
RIE = 1?
N
N
Y
TDRE = 1?
Freescale Semiconductor, Inc...
Y
Y
N
Y
Y
TE = 1?
TIE = 1?
N
N
RE = 1?
N
Y
Y
TCIE = 1?
TC = 1?
N
N
Y
IDLE = 1?
Y
ILIE = 1?
N
N
Y
RE = 1?
N
NO
VALID SCI REQUEST
VALID SCI REQUEST
INT SOURCE RES
Figure 7-4 Interrupt Source Resolution within SCI
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SECTION 8
SERIAL PERIPHERAL INTERFACE
The serial peripheral interface (SPI), an independent serial communications subsystem, allows the MCU to communicate synchronously with peripheral devices, such
as transistor-transistor logic (TTL) shift registers, liquid crystal diode (LCD) display
drivers, analog-to-digital converter subsystems, and other microprocessors. The SPI
is also capable of inter-processor communication in a multiple master system. The SPI
system can be configured as either a master or a slave device with data rates as high
as one half of the E-clock rate when configured as master, and as fast as the E-clock
rate when configured as slave.
8.1 Functional Description
The central element in the SPI system is the block containing the shift register and the
read data buffer. The system is single buffered in the transmit direction and double
buffered in the receive direction. This means that new data for transmission cannot be
written to the shifter until the previous transfer is complete; however, received data is
transferred into a parallel read data buffer so the shifter is free to accept a second serial character. As long as the first character is read out of the read data buffer before
the next serial character is ready to be transferred, no overrun condition occurs. A single MCU register address is used for reading data from the read data buffer, and for
writing data to the shifter.
The SPI status block represents the SPI status functions (transfer complete, write collision, and mode fault) performed by the serial peripheral status register (SPSR). The
SPI control block represents those functions that control the SPI system through the
serial peripheral control register (SPCR).
Refer to Figure 8-1, which shows the SPI block diagram.
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INTERNAL
MCU CLOCK
MISO
PD2
S
M
LSB
M
S
8/16-BIT SHIFT REGISTER
÷16 ÷32
READ DATA BUFFER
CLOCK
S
CLOCK
LOGIC
SCK
PD4
M
SPR0
DWOM
SS
PD5
MSTR
SPR1
MOSI
PD3
MSTR
SPR0
SPR1
CPHA
CPOL
MSTR
DWOM
SPIE
MODF
WCOL
SPE
SPE
SPI CONTROL
SPIF
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SELECT
SPI CLOCK (MASTER)
SPE
÷4
PIN CONTROL LOGIC
MSB
DIVIDER
÷2
8
SPI STATUS REGISTER
SPI CONTROL REGISTER
8
SPI INTERRUPT
REQUEST
8
INTERNAL
DATA BUS
11 SPI BLOCK
Figure 8-1 SPI Block Diagram
8.2 SPI Transfer Formats
During an SPI transfer, data is simultaneously transmitted and received. A serial clock
line synchronizes shifting and sampling of the information on the two serial data lines.
A slave select line allows individual selection of a slave SPI device; slave devices that
are not selected do not interfere with SPI bus activities. On a master SPI device, the
select line can optionally be used to indicate a multiple master bus contention. Refer
to Figure 8-2.
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1
SCK CYCLE #
2
3
4
5
6
7
8
SCK (CPOL = 0)
SCK (CPOL = 1)
SAMPLE INPUT
MSB
(CPHA = 0) DATA OUT
6
5
4
3
2
1
LSB
SAMPLE INPUT
MSB
(CPHA = 1) DATA OUT
6
5
4
3
2
1
LSB
SS (TO SLAVE)
Freescale Semiconductor, Inc...
SLAVE CPHA=1 TRANSFER IN PROGRESS
3
MASTER TRANSFER IN PROGRESS
2
4
SLAVE CPHA=0 TRANSFER IN PROGRESS
1
5
1. SS ASSERTED
2. MASTER WRITES TO SPDR
3. FIRST SCK EDGE
4. SPIF SET
5. SS NEGATED
SPI TRANSFER FORMAT 1
Figure 8-2 SPI Transfer Format
8.2.1 Clock Phase and Polarity Controls
Software can select one of four combinations of serial clock phase and polarity using
two bits in the SPI control register (SPCR). The clock polarity is specified by the CPOL
control bit, which selects an active high or active low clock, and has no significant effect on the transfer format. The clock phase (CPHA) control bit selects one of two different transfer formats. The 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 transfers to allow a master device to communicate with peripheral slaves having different requirements.
When CPHA equals zero, the slave select (SS) line must be negated and reasserted
between each successive serial byte. Also, if the slave writes data to the SPI data register (SPDR) while SS is active low, a write collision error results.
When CPHA equals one, the SS line can remain low between successive transfers.
8.3 SPI Signals
The following paragraphs contain descriptions of the four SPI signals: master in slave
out (MISO), master out slave in (MOSI), serial clock (SCK), and SS.
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8.3.1 Master In Slave Out
MISO is one of two unidirectional serial data signals. It is an input to a master device
and an output from a slave device. The MISO line of a slave device is placed in the
high impedance state if the slave device is not selected.
Freescale Semiconductor, Inc...
8.3.2 Master Out Slave In
The MOSI line is the second of the two unidirectional serial data signals. It is an output
from a master device and an input to a slave device. The master device places data
on the MOSI line a half-cycle before the clock edge that the slave device uses to latch
the data.
8.3.3 Serial Clock
SCK, an input to a slave device, is generated by the master device and synchronizes
data movement in and out of the device through the MOSI and MISO lines. Master and
slave devices are capable of exchanging a byte of information during a sequence of
eight clock cycles.
There are four possible timing relationships that can be chosen by using control bits
CPOL and CPHA in the serial peripheral control register (SPCR). Both master and
slave devices must operate with the same timing. The SPI clock rate select bits,
SPR[1:0], in the SPCR of the master device, select the clock rate. In a slave device,
SPR[1:0] have no effect on the operation of the SPI.
8.3.4 Slave Select
The SS input of a slave device must be externally asserted before a master device can
exchange data with the slave device. must be low before data transactions and must
stay low for the duration of the transaction.
The SS line of the master must be held high. If it goes low, a mode fault error flag
(MODF) is set in the serial peripheral status register (SPSR). To disable the mode fault
circuit, write a one in bit 5 of the port D data direction register. This sets the SS pin to
act as a general-purpose output. The other three lines are dedicated to the SPI whenever the serial peripheral interface is on.
The state of the master and slave CPHA bits affects the operation of SS. CPHA settings should be identical for master and slave. When CPHA = 0, the shift clock is the
OR of SS with SCK. In this clock phase mode, SS must go high between successive
characters in an SPI message. When CPHA = 1, SS can be left low between successive SPI characters. In cases where there is only one SPI slave MCU, its SS line can
be tied to VSS as long as only CPHA = 1 clock mode is used.
8.4 SPI System Errors
Two system errors can be detected by the SPI system. The first type of error arises in
a multiple-master system when more than one SPI device simultaneously tries to be
a master. This error is called a mode fault. The second type of error, write collision,
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indicates that an attempt was made to write data to the SPDR while a transfer was in
progress.
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When the SPI system is configured as a master and the SS input line goes to active
low, a mode fault error has occurred — usually because two devices have attempted
to act as master at the same time. In cases where more than one device is concurrently configured as a master, there is a chance of contention between two pin drivers. For
push-pull CMOS drivers, this contention can cause permanent damage. The mode
fault attempts to protect the device by disabling the drivers. The MSTR control bit in
the SPCR and all four DDRD control bits associated with the SPI are cleared. An interrupt is generated subject to masking by the SPIE control bit and the I bit in the CCR.
Other precautions may need to be taken to prevent driver damage. If two devices are
made masters at the same time, mode fault does not help protect either one unless
one of them selects the other as slave. The amount of damage possible depends on
the length of time both devices attempt to act as master.
A write collision error occurs if the SPDR is written while a transfer is in progress. Because the SPDR is not double buffered in the transmit direction, writes to SPDR cause
data to be written directly into the SPI shift register. Because this write corrupts any
transfer in progress, a write collision error is generated. The transfer continues undisturbed, and the write data that caused the error is not written to the shifter.
A write collision is normally a slave error because a slave has no control over when a
master initiates a transfer. A master knows when a transfer is in progress, so there is
no reason for a master to generate a write-collision error, although the SPI logic can
detect write collisions in both master and slave devices.
The SPI configuration determines the characteristics of a transfer in progress. For a
master, a transfer begins when data is written to SPDR and ends when SPIF is set.
For a slave with CPHA equal to zero, a transfer starts when SS goes low and ends
when SS returns high. In this case, SPIF is set at the middle of the eighth SCK cycle
when data is transferred from the shifter to the parallel data register, but the transfer
is still in progress until SS goes high. For a slave with CPHA equal to one, transfer begins when the SCK line goes to its active level, which is the edge at the beginning of
the first SCK cycle. The transfer ends in a slave in which CPHA equals one when SPIF
is set. For a slave, after a byte transfer, SCK must be in inactive state for at least 2 Eclock cycles before the next byte transfer begins.
8.5 SPI Registers
The three SPI registers, SPCR, SPSR, and SPDR, provide control, status, and data
storage functions. Refer to the following information for a description of how these registers are organized.
SERIAL PERIPHERAL INTERFACE
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8.5.1 Serial Peripheral Control
SPCR — Serial Peripheral Control Register
RESET:
Bit 7
SPIE
0
6
SPE
0
5
DWOM
0
4
MSTR
0
$0028
3
CPOL
0
2
CPHA
1
1
SPR1
U
Bit 0
SPR0
U
SPIE — Serial Peripheral Interrupt Enable
0 = SPI interrupt disabled
1 = SPI interrupt enabled
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SPE — Serial Peripheral System Enable
0 = SPI off
1 = SPI on
DWOM — Port D Wired-OR Mode
DWOM affects all six port D pins.
0 = Normal CMOS outputs
1 = Open-drain outputs
MSTR — Master Mode Select
0 = Slave mode
1 = Master mode
CPOL — Clock Polarity
When the clock polarity bit is cleared and data is not being transferred, the SCK pin of
the master device has a steady state low value. When CPOL is set, SCK idles high.
Refer to Figure 8-2 and 8.2.1 Clock Phase and Polarity Controls.
CPHA — Clock Phase
The clock phase bit, in conjunction with the CPOL bit, controls the clock-data relationship between master and slave. The CPHA bit selects one of two different clocking
protocols. Refer to Figure 8-2 and 8.2.1 Clock Phase and Polarity Controls.
SPR1 and SPR0 — SPI Clock Rate Selects
These two serial peripheral rate bits select one of four baud rates to be used as SCK
if the device is a master; however, they have no effect in the slave mode.
SPR[1:0]
00
01
10
11
E Clock
Divide By
2
4
16
32
Frequency at
E = 2 MHz (Baud)
1.0 MHz
500 kHz
125 kHz
62.5 kHz
SERIAL PERIPHERAL INTERFACE
8-6
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8.5.2 Serial Peripheral Status
SPSR — Serial Peripheral Status Register
RESET:
Bit 7
SPIF
0
6
WCOL
0
5
0
0
$0029
4
MODF
0
3
0
0
2
0
0
1
0
0
Bit 0
0
0
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SPIF — SPI Transfer Complete Flag
SPIF is set upon completion of data transfer between the processor and the external
device. If SPIF goes high, and if SPIE is set, a serial peripheral interrupt is generated.
To clear the SPIF bit, read the SPSR with SPIF set, then access the SPDR. Unless
SPSR is read (with SPIF set) first, attempts to write SPDR are inhibited.
WCOL — Write Collision
Clearing the WCOL bit is accomplished by reading the SPSR (with WCOL set) followed by an access of SPDR. Refer to 8.3.4 Slave Select and 8.4 SPI System Errors.
0 = No write collision
1 = Write collision
Bit 5 — Not implemented
Always reads zero
MODF — Mode Fault
To clear the MODF bit, read the SPSR (with MODF set), then write to the SPCR. Refer
to 8.3.4 Slave Select and 8.4 SPI System Errors.
0 = No mode fault
1 = Mode fault
Bits [3:0] — Not implemented
Always read zero
8.5.3 Serial Peripheral Data I/O
The SPDR is used when transmitting or receiving data on the serial bus. Only a write
to this register initiates transmission or reception of a byte, and this only occurs in the
master device. At the completion of transferring a byte of data, the SPIF status bit is
set in both the master and slave devices.
A read of the SPDR is actually a read of a buffer. To prevent an overrun and the loss
of the byte that caused the overrun, the first SPIF must be cleared by the time a second
transfer of data from the shift register to the read buffer is initiated.
SPDR — SPI Data Register
Bit 7
Bit 7
6
6
$002A
5
5
4
4
3
3
2
2
1
1
Bit 0
Bit 0
NOTE
SPI is double buffered in and single buffered out.
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SERIAL PERIPHERAL INTERFACE
8-8
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SECTION 9
TIMING SYSTEM
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The M68HC11 timing system is composed of five clock divider chains. The main clock
divider chain includes a 16-bit free-running counter, which is driven by a programmable prescaler. The main timer's programmable prescaler provides one of the four
clocking rates to drive the 16-bit counter. Two prescaler control bits select the prescale
rate.
The prescaler output divides the system clock by 1, 4, 8, or 16. Taps off of this main
clocking chain drive circuitry that generates the slower clocks used by the pulse accumulator, the real-time interrupt (RTI), and the computer operating properly (COP)
watchdog subsystems, also described in this section. Refer to Figure 9-1.
All main timer system activities are referenced to this free-running counter. The
counter begins incrementing from $0000 as the MCU comes out of reset, and continues to the maximum count, $FFFF. At the maximum count, the counter rolls over to
$0000, sets an overflow flag, and continues to increment. As long as the MCU is running in a normal operating mode, there is no way to reset, change, or interrupt the
counting. The capture/compare subsystem features three input capture channels, four
output compare channels, and one channel that can be selected to perform either input capture or output compare. Each of the three input capture functions has its own
16-bit input capture register (time capture latch) and each of the output compare functions has its own 16-bit compare register. All timer functions, including the timer overflow and RTI have their own interrupt controls and separate interrupt vectors.
The pulse accumulator contains an 8-bit counter and edge select logic. The pulse accumulator can operate in either event counting or gated time accumulation modes.
During event counting mode, the pulse accumulator's 8-bit counter increments when
a specified edge is detected on an input signal. During gated time accumulation mode,
an internal clock source increments the 8-bit counter while an input signal has a predetermined logic level.
RTI is a programmable periodic interrupt circuit that permits pacing the execution of
software routines by selecting one of four interrupt rates.
The COP watchdog clock input (E÷215) is tapped off of the free-running counter chain.
The COP automatically times out unless it is serviced within a specific time by a program reset sequence. If the COP is allowed to time out, a reset is generated, which
drives the RESET pin low to reset the MCU and the external system. Refer to Table
9-1 for crystal related frequencies and periods.
TIMING SYSTEM
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OSCILLATOR AND
CLOCK GENERATOR
(DIVIDE BY FOUR)
AS
E CLOCK
INTERNAL BUS CLOCK (PH2)
PRESCALER
(÷ 2, 4, 16, 32)
SPR[1:0]
SPI
PRESCALER
(÷ 1, 2, 4,....128)
SCR[2:0]
PRESCALER
(÷ 1, 3, 4, 13)
SCP[1:0]
SCI RECEIVER CLOCK
÷16
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E÷26
SCI TRANSMIT CLOCK
PULSE ACCUMULATOR
PRESCALER
(÷ 1, 2, 4, 8)
RTR[1:0]
E÷213
REAL-TIME INTERRUPT
÷4
E÷2 15
PRESCALER
(÷ 1, 4, 8, 16)
PR[1:0]
PRESCALER
(÷1, 4, 16, 64)
CR[1:0]
TOF
TCNT
FF1
S
Q
R
Q
FF2
S
Q
R
Q
FORCE
COP
RESET
IC/OC
CLEAR COP
TIMER
SYSTEM
RESET
TIMER DIV CHAIN
Figure 9-1 Timer Clock Divider Chains
TIMING SYSTEM
9-2
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Table 9-1 Timer Summary
4.0 MHz
1.0 MHz
1000 ns
XTAL Frequencies
8.0 MHz
12.0 MHz
2.0 MHz
3.0 MHz
500 ns
333 ns
Main Timer Count Rates
Other Rates
(E)
(1/E)
Control
Bits
PR[1:0]
00
1 count —
overflow —
1.0 µs
65.536 ms
500 ns
32.768 ms
333 ns
21.845 ms
(E/1)
(E/216)
01
1 count —
overflow —
4.0 µs
262.14 ms
2.0 µs
131.07 ms
1.333 µs
87.381 ms
(E/4)
(E/218)
10
1 count —
overflow —
8.0 µs
524.29 ms
4.0 µs
262.14 ms
2.667 µs
174.76 ms
(E/8)
(E/219)
11
1 count —
overflow —
16.0 µs
1.049 s
8.0 µs
524.29 ms
5.333 µs
349.52 ms
(E/16)
(E/220)
9.1 Timer Structure
Figure 9-1 shows the capture/compare system block diagram. The port A pin control
block includes logic for timer functions and for general-purpose I/O. For pins PA2,
PA1, and PA0, this block contains both the edge-detection logic and the control logic
that enables the selection of which edge triggers an input capture. The digital level on
PA[2:0] can be read at any time (read PORTA register), even if the pin is being used
for the input capture function. Pins PA[6:4] are used for either general-purpose output,
or as output compare pins. Pin PA3 can be used for general-purpose I/O, input capture
4, output compare 5, or output compare 1. When one of these pins is being used for
an output compare function, it cannot be written directly as if it were a general-purpose
output. Each of the output compare functions (OC5–OC2) is related to one of the port
A output pins. Output compare one (OC1) has extra control logic, allowing it optional
control of any combination of the PA[7:3] pins. The PA7 pin can be used as a generalpurpose I/O pin, as an input to the pulse accumulator, or as an OC1 output pin.
TIMING SYSTEM
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SYSTEM
CLOCK
PRESCALER — DIVIDE BY
1, 4, 8, 16
PR1
TCNT (HI)
TCNT (LO)
16-BIT FREE RUNNING
PR0
TOI
9
TOF
COUNTER
INTERRUPT REQUESTS
16-BIT TIMER BUS
OC1I
16-BIT COMPARATOR =
TOC1 (HI)
OC1F
TOC1 (LO)
FOC1
OC2I
16-BIT COMPARATOR =
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TOC2 (HI)
TOC2 (LO)
TOC3 (LO)
TOC4 (LO)
OC5
TI4/O5 (LO)
I4/O5F
16-BIT LATCH CLK
TIC3 (HI)
PA4
OC4/OC1
BIT 3
PA3
IC4/OC5
OC1
BIT 2
PA2
IC1
BIT 1
PA1
IC2
BIT 3
PA0
IC3
IC4
IC1I
CLK
CLK
IC2I
2
IC2F
TIC2 (LO)
CLK
3
IC1F
TIC1 (LO)
16-BIT LATCH
BIT 4
4
FOC5
I4/O5
TIC2 (HI)
PA5
OC3/OC1
5
FOC4
16-BIT COMPARATOR =
16-BIT LATCH
BIT 5
OC4F
I4/O5I
TIC1 (HI)
PA6
OC2/OC1
6
FOC3
16-BIT COMPARATOR =
16-BIT LATCH
BIT 6
OC3F
OC4I
TI4/O5 (HI)
PA7
OC1
7
FOC2
16-BIT COMPARATOR =
TOC4 (HI)
BIT 7
OC2F
OC3I
TOC3 (HI)
PIN
FUNCTIONS
8
IC3I
IC3F
1
TIC3 (LO)
TFLG 1
STATUS
FLAGS
TMSK 1
CFORC
FORCE OUTPUT INTERRUPT
ENABLES
COMPARE
PARALLEL PORT
PIN CONTROL
11 CC BLOCK
Figure 9-2 Capture/Compare Block Diagram
9.2 Input Capture
The input capture function records the time an external event occurs by latching the
value of the free-running counter when a selected edge is detected at the associated
timer input pin. Software can store latched values and use them to compute the periodicity and duration of events. For example, by storing the times of successive edges
of an incoming signal, software can determine the period and pulse width of a signal.
To measure period, two successive edges of the same polarity are captured. To measure pulse width, two alternate polarity edges are captured.
TIMING SYSTEM
9-4
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In most cases, input capture edges are asynchronous to the internal timer counter,
which is clocked relative to the PH2 clock. These asynchronous capture requests are
synchronized to PH2 so that the latching occurs on the opposite half cycle of PH2 from
when the timer counter is being incremented. This synchronization process introduces
a delay from when the edge occurs to when the counter value is detected. Because
these delays offset each other when the time between two edges is being measured,
the delay can be ignored. When an input capture is being used with an output compare, there is a similar delay between the actual compare point and when the output
pin changes state.
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The control and status bits that implement the input capture functions are contained in
the PACTL, TCTL2, TMSK1, and TFLG1 registers.
To configure port A bit 3 as an input capture, clear the DDRA3 bit of the PACTL register. Note that this bit is cleared out of reset. To enable PA3 as the fourth input capture, set the I4/O5 bit in the PACTL register. Otherwise, PA3 is configured as a fifth
output compare out of reset, with bit I4/O5 being cleared. If the DDRA3 bit is set (configuring PA3 as an output), and IC4 is enabled, then writes to PA3 cause edges on the
pin to result in input captures. Writing to TI4/O5 has no effect when the TI4/O5 register
is acting as IC4.
9.2.1 Timer Control 2 Register
Use the control bits of this register to program input capture functions to detect a particular edge polarity on the corresponding timer input pin. Each of the input capture
functions can be independently configured to detect rising edges only, falling edges
only, any edge (rising or falling), or to disable the input capture function. The input capture functions operate independently of each other and can capture the same TCNT
value if the input edges are detected within the same timer count cycle.
TCTL2 — Timer Control 2
RESET:
Bit 7
EDG4B
0
6
EDG4A
0
$0021
5
EDG1B
0
4
EDG1A
0
3
EDG2B
0
2
EDG2A
0
1
EDG3B
0
Bit 0
EDG3A
0
EDGxB and EDGxA — Input Capture Edge Control
There are four pairs of these bits. Each pair is cleared to zero by reset and must be
encoded to configure the corresponding input capture edge detector circuit. IC4 functions only if the I4/O5 bit in the PACTL register is set. Refer to Table 9-2 for timer control configuration.
Table 9-2 Timer Control Configuration
EDGxB
0
0
1
1
EDGxA
0
1
0
1
Configuration
Capture disabled
Capture on rising edges only
Capture on falling edges only
Capture on any edge
TIMING SYSTEM
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9.2.2 Timer Input Capture Registers
When an edge has been detected and synchronized, the 16-bit free-running counter
value is transferred into the input capture register pair as a single 16-bit parallel transfer. Timer counter value captures and timer counter incrementing occur on opposite
half-cycles of the phase two clock so that the count value is stable whenever a capture
occurs. The TICx registers are not affected by reset. Input capture values can be read
from a pair of 8-bit read-only registers. A read of the high-order byte of an input capture
register pair inhibits a new capture transfer for one bus cycle. If a double-byte read instruction, such as LDD, is used to read the captured value, coherency is assured.
When a new input capture occurs immediately after a high-order byte read, transfer is
delayed for an additional cycle but the value is not lost.
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TIC1–TIC3 — Timer Input Capture
$0010–$0015
$0010
Bit 15
14
13
12
11
10
9
Bit 8
TIC1 (High)
$0011
Bit 7
6
5
4
3
2
1
Bit 0
TIC1 (Low)
$0012
Bit 15
14
13
12
11
10
9
Bit 8
TIC2 (High)
$0013
Bit 7
6
5
4
3
2
1
Bit 0
TIC2 (Low)
$0014
Bit 15
14
13
12
11
10
9
Bit 8
TIC3 (High)
$0015
Bit 7
6
5
4
3
2
1
Bit 0
TIC3 (Low)
RESET:
Input capture registers not affected by reset.
9.2.3 Timer Input Capture 4/Output Compare 5 Register
Use TI4/O5 as either an input capture register or an output compare register, depending on the function chosen for the I4/O5 pin. To enable it as an input capture pin, set
the I4/O5 bit in the pulse accumulator control register (PACTL) to logic level one. To
use it as an output compare register, set the I4/O5 bit to a logic level zero. Refer to 9.6
Pulse Accumulator.
TI4/O5 — Timer Input Capture 4/Output Compare 5
$001E
$001F
RESET:
Bit 15
Bit 7
14
6
13
12
11
10
9
5
4
3
2
1
All I4/O5 register pairs reset to ones ($FFFF).
$001E, $001F
Bit 8
Bit 0
TI4/O5 (High)
TI4/O5 (Low)
9.3 Output Compare
Use the output compare (OC) function to program an action to occur at a specific time
— when the 16-bit counter reaches a specified value. For each of the five output compare functions, there is a separate 16-bit compare register and a dedicated 16-bit comparator. The value in the compare register is compared to the value of the free-running
counter on every bus cycle. When the compare register matches the counter value, an
output compare status flag is set. The flag can be used to initiate the automatic actions
for that output compare function.
To produce a pulse of a specific duration, write to the output compare register a value
representing the time the leading edge of the pulse is to occur. The output compare
circuit is configured to set the appropriate output either high or low, depending on the
TIMING SYSTEM
9-6
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polarity of the pulse being produced. After a match occurs, the output compare register
is reprogrammed to change the output pin back to its inactive level at the next match.
A value representing the width of the pulse is added to the original value, and then written to the output compare register. Because the pin state changes occur at specific
values of the free-running counter, the pulse width can be controlled accurately at the
resolution of the free-running counter, independent of software latencies. To generate
an output signal of a specific frequency and duty cycle, repeat this pulse-generating
procedure.
There are four 16-bit read/write output compare registers: TOC1, TOC2, TOC3, and
TOC4, and the TI4/O5 register, which functions under software control as either IC4
or OC5. Each of the OC registers is set to $FFFF on reset. A value written to an OC
register is compared to the free-running counter value during each E-clock cycle. If a
match is found, the particular output compare flag is set in timer interrupt flag register
1 (TFLG1). If that particular interrupt is enabled in the timer interrupt mask register 1
(TMSK1), an interrupt is generated. In addition to an interrupt, a specified action can
be initiated at one or more timer output pins. For OC5–OC2, the pin action is controlled
by pairs of bits (OMx and OLx) in the TCTL1 register. The output action is taken on
each successful compare, regardless of whether or not the OCxF flag in the TFLG1
register was previously cleared.
OC1 is different from the other output compares in that a successful OC1 compare can
affect any or all five of the OC pins. The OC1 output action taken when a match is
found is controlled by two 8-bit registers with three bits unimplemented: the output
compare 1 mask register, OC1M, and the output compare 1 data register, OC1D.
OC1M specifies which port A outputs are to be used, and OC1D specifies what data
is placed on these port pins.
9.3.1 Timer Output Compare Registers
All output compare registers are 16-bit read-write. Each is initialized to $FFFF at reset.
If an output compare register is not used for an output compare function, it can be used
as a storage location. A write to the high-order byte of an output compare register pair
inhibits the output compare function for one bus cycle. This inhibition prevents inappropriate subsequent comparisons. Coherency requires a complete 16-bit read or
write. However, if coherency is not needed, byte accesses can be used.
For output compare functions, write a comparison value to output compare registers
TOC1–TOC4 and TI4/O5. When TCNT value matches the comparison value, specified pin actions occur.
TIMING SYSTEM
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TOC1–TOC4 — Timer Output Compare
$0016–$001D
$0016
Bit 15
14
13
12
11
10
9
Bit 8
TOC1 (High)
$0017
Bit 7
6
5
4
3
2
1
Bit 0
TOC1 (Low)
$0018
Bit 15
14
13
12
11
10
9
Bit 8
TOC2 (High)
$0019
Bit 7
6
5
4
3
2
1
Bit 0
TOC2 (Low)
$001A
Bit 15
14
13
12
11
10
9
Bit 8
TOC3 (High)
$001B
Bit 7
6
5
4
3
2
1
Bit 0
TOC3 (Low)
$001C
Bit 15
14
13
12
11
10
9
Bit 8
TOC4 (High)
$001D
Bit 7
6
5
4
3
2
1
Bit 0
TOC4 (Low)
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All TOCx register pairs reset to ones ($FFFF)
TI4/O5 — Timer Input Capture 4/Output Compare 5
$001E, $001F
Refer to 9.2.3 Timer Input Capture 4/Output Compare 5 Register.
9.3.2 Timer Compare Force Register
The CFORC register allows forced early compares. FOC[1:5] correspond to the five
output compares. These bits are set for each output compare that is to be forced. The
action taken as a result of a forced compare is the same as if there were a match between the OCx register and the free-running counter, except that the corresponding
interrupt status flag bits are not set. The forced channels trigger their programmed pin
actions to occur at the next timer count transition after the write to CFORC.
The CFORC bits should not be used on an output compare function that is programmed to toggle its output on a successful compare because a normal compare that
occurs immediately before or after the force can result in an undesirable operation.
CFORC — Timer Compare Force
RESET:
Bit 7
FOC1
0
6
FOC2
0
5
FOC3
0
$000B
4
FOC4
0
3
FOC5
0
2
0
0
1
0
0
Bit 0
0
0
FOC1–FOC5 — Write Ones to Force Compare(s)
0 = Not affected
1 = Output x action occurs
Bits [2:0] — Not implemented, always read zero
9.3.3 Output Compare Mask Registers
Use OC1M with OC1 to specify the bits of port A that are affected by a successful OC1
compare. The bits of the OC1M register correspond to PA[7:3].
TIMING SYSTEM
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OC1M — Output Compare 1 Mask
RESET:
Bit 7
OC1M7
0
6
OC1M6
0
$000C
5
OC1M5
0
4
OC1M4
0
3
OC1M3
0
2
0
0
1
0
0
Bit 0
0
0
OC1M7–OC1M3 — Output Compare Masks
0 = OC1 is disabled
1 = OC1 is enabled to control the corresponding pin of port A
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Bits [2:0] — Not implemented; always read zero
Set bit(s) to enable OC1 to control corresponding pin(s) of port A.
9.3.4 Output Compare 1 Data Register
Use this register with OC1 to specify the data that is to be stored on the affected pin
of port A after a successful OC1 compare. When a successful OC1 compare occurs,
a data bit in OC1D is stored in the corresponding bit of port A for each bit that is set in
OC1M.
OC1D — Output Compare 1 Data
RESET:
Bit 7
OC1D7
0
6
OC1D6
0
$000D
5
OC1D5
0
4
OC1D4
0
3
OC1D3
0
2
0
0
1
0
0
Bit 0
0
0
If OC1Mx is set, data in OC1Dx is output to port A bit x on successful OC1 compares.
Bits [2:0] — Not implemented; always read zero
9.3.5 Timer Counter Register
The 16-bit read-only TCNT register contains the prescaled value of the 16-bit timer. A
full counter read addresses the most significant byte (MSB) first. A read of this address
causes the least significant byte (LSB) to be latched into a buffer for the next CPU cycle so that a double-byte read returns the full 16-bit state of the counter at the time of
the MSB read cycle.
TCNT — Timer Counter
$000E
$000F
Bit 15
Bit 7
14
6
$000E, $000F
13
5
12
4
11
3
10
2
9
1
Bit 8
Bit 0
TCNT (High)
TCNT (Low)
TCNT resets to $0000.
In normal modes, TCNT is read-only.
9.3.6 Timer Control 1 Register
The bits of this register specify the action taken as a result of a successful OCx compare.
TIMING SYSTEM
TECHNICAL DATA
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TCTL1 — Timer Control 1
RESET:
Bit 7
OM2
0
6
OL2
0
$0020
5
OM3
0
4
OL3
0
3
OM4
0
2
OL4
0
1
OM5
0
Bit 0
OL5
0
OM[2:5] — Output Mode
Freescale Semiconductor, Inc...
OL[2:5] — Output Level
These control bit pairs are encoded to specify the action taken after a successful OCx
compare. OC5 functions only if the I4/O5 bit in the PACTL register is clear. Refer to
the following table for the coding.
OMx
0
0
1
1
OLx
0
1
0
1
Action Taken on Successful Compare
Timer disconnected from output pin logic
Toggle OCx output line
Clear OCx output line to 0
Set OCx output line to 1
9.3.7 Timer Interrupt Mask 1 Register
Use this 8-bit register to enable or inhibit the timer input capture and output compare
interrupts.
TMSK1 — Timer Interrupt Mask 1
RESET:
Bit 7
OC1I
0
6
OC2I
0
5
OC3I
0
$0022
4
OC4I
0
3
I4/O5I
0
2
IC1I
0
1
IC2I
0
Bit 0
IC3I
0
OC1I–OC4I — Output Compare x Interrupt Enable
If the OCxI enable bit is set when the OCxF flag bit is set, a hardware interrupt sequence is requested.
I4/O5I — Input Capture 4 or Output Compare 5 Interrupt Enable
When I4/O5 in PACTL is one, I4/O5I is the input capture 4 interrupt enable bit. When
I4/O5 in PACTL is zero, I4/O5I is the output compare 5 interrupt enable bit.
IC1I–IC3I — Input Capture x Interrupt Enable
If the ICxI enable bit is set when the ICxF flag bit is set, a hardware interrupt sequence
is requested.
NOTE
Bits in TMSK1 correspond bit for bit with flag bits in TFLG1. Ones in
TMSK1 enable the corresponding interrupt sources.
9.3.8 Timer Interrupt Flag 1 Register
Bits in this register indicate when timer system events have occurred. Coupled with the
bits of TMSK1, the bits of TFLG1 allow the timer subsystem to operate in either a
TIMING SYSTEM
9-10
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TECHNICAL DATA
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polled or interrupt driven system. Each bit of TFLG1 corresponds to a bit in TMSK1 in
the same position.
TFLG1 — Timer Interrupt Flag 1
RESET:
Bit 7
OC1F
0
6
OC2F
0
$0023
5
OC3F
0
4
OC4F
0
3
I4/O5F
0
2
IC1F
0
1
IC2F
0
Bit 0
IC3F
0
Clear flags by writing a one to the corresponding bit position(s).
Freescale Semiconductor, Inc...
OC1F–OC5F — Output Compare x Flag
Set each time the counter matches output compare x value
I4/O5F — Input Capture 4/Output Compare 5 Flag
Set by IC4 or OC5, depending on the function enabled by I4/O5 bit in PACTL
IC1F–IC3F — Input Capture x Flag
Set each time a selected active edge is detected on the ICx input line
9.3.9 Timer Interrupt Mask 2 Register
Use this 8-bit register to enable or inhibit timer overflow and real-time interrupts. The
timer prescaler control bits are included in this register.
TMSK2 — Timer Interrupt Mask 2
RESET:
Bit 7
TOI
0
6
RTII
0
$0024
5
PAOVI
0
4
PAII
0
3
0
0
2
0
0
1
PR1
0
Bit 0
PR0
0
TOI — Timer Overflow Interrupt Enable
0 = TOF interrupts disabled
1 = Interrupt requested when TOF is set to one
RTII — Real-time Interrupt Enable
Refer to 9.4 Real-Time Interrupt.
PAOVI — Pulse Accumulator Overflow Interrupt Enable
Refer to 9.6 Pulse Accumulator.
PAII — Pulse Accumulator Input Edge Interrupt Enable
Refer to 9.6 Pulse Accumulator.
NOTE
Bits in TMSK2 correspond bit for bit with flag bits in TFLG2. Ones in
TMSK2 enable the corresponding interrupt sources.
TIMING SYSTEM
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PR[1:0] — Timer Prescaler Select
These bits are used to select the prescaler divide-by ratio. In normal modes, PR[1:0]
can only be written once, and the write must be within 64 cycles after reset. Refer to
Table 9-1 for specific timing values.
Freescale Semiconductor, Inc...
PR[1:0]
00
01
10
11
Prescaler
1
4
8
16
9.3.10 Timer Interrupt Flag 2 Register
Bits in this register indicate when certain timer system events have occurred. Coupled
with the four high-order bits of TMSK2, the bits of TFLG2 allow the timer subsystem to
operate in either a polled or interrupt driven system. Each bit of TFLG2 corresponds
to a bit in TMSK2 in the same position.
TFLG2 — Timer Interrupt Flag 2
RESET:
Bit 7
TOF
0
6
RTIF
0
$0025
5
PAOVF
0
4
PAIF
0
3
0
0
2
0
0
1
0
0
Bit 0
0
0
Clear flags by writing a one to the corresponding bit position(s).
TOF — Timer Overflow Interrupt Flag
Set when TCNT changes from $FFFF to $0000
RTIF — Real-Time (Periodic) Interrupt Flag
Refer to 9.4 Real-Time Interrupt.
PAOVF — Pulse Accumulator Overflow Interrupt Flag
Refer to 9.6 Pulse Accumulator.
PAIF — Pulse Accumulator Input Edge Interrupt Flag
Refer to 9.6 Pulse Accumulator.
Bits [3:0]— Not implemented
Always read zero
9.4 Real-Time Interrupt
The real-time interrupt feature, used to generate hardware interrupts at a fixed periodic
rate, is controlled and configured by two bits (RTR1 and RTR0) in the pulse accumulator control (PACTL) register. The RTII bit in the TMSK2 register enables the interrupt
capability. The four different rates available are a product of the MCU oscillator frequency and the value of bits RTR[1:0]. Refer to the following table, which shows the
periodic real-time interrupt rates.
TIMING SYSTEM
9-12
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RTR[1:0]
00
01
10
11
E = 1 MHz
2.731 ms
5.461 ms
10.923 ms
21.845 ms
E = 2 MHz
4.096 ms
8.192 ms
16.384 ms
32.768 ms
E = 3 MHz
8.192 ms
16.384 ms
32.768 ms
65.536 ms
E = X MHz
(E/213)
(E/214)
(E/215)
(E/216)
Freescale Semiconductor, Inc...
The clock source for the RTI function is a free-running clock that cannot be stopped or
interrupted except by reset. This clock causes the time between successive RTI timeouts to be a constant that is independent of the software latencies associated with flag
clearing and service. For this reason, an RTI period starts from the previous time-out,
not from when RTIF is cleared.
Every time-out causes the RTIF bit in TFLG2 to be set, and if RTII is set, an interrupt
request is generated. After reset, one entire real-time interrupt period elapses before
the RTIF flag is set for the first time. Refer to the TMSK2, TFLG2, and PACTL registers.
9.4.1 Timer Interrupt Mask 2 Register
This register contains the real-time interrupt enable bits.
TMSK2 — Timer Interrupt Mask 2
RESET:
Bit 7
TOI
0
6
RTII
0
$0024
5
PAOVI
0
4
PAII
0
3
0
0
2
0
0
1
PR1
0
Bit 0
PR0
0
TOI — Timer Overflow Interrupt Enable
Refer to 9.3 Output Compare.
RTII — Real-time Interrupt Enable
0 = RTIF interrupts disabled
1 = Interrupt requested when RTIF is set to one
PAOVI — Pulse Accumulator Overflow Interrupt Enable
Refer to 9.6 Pulse Accumulator.
PAII — Pulse Accumulator Input Edge
Refer to 9.6 Pulse Accumulator.
NOTE
Bits in TMSK2 correspond bit for bit with flag bits in TFLG2. Ones in
TMSK2 enable the corresponding interrupt sources.
9.4.1 Timer Interrupt Flag 2 Register
Bits of this register indicate the occurrence of timer system events. Coupled with the
four high-order bits of TMSK2, the bits of TFLG2 allow the timer subsystem to operate
in either a polled or interrupt driven system. Each bit of TFLG2 corresponds to a bit in
TMSK2 in the same position.
TIMING SYSTEM
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TFLG2 — Timer Interrupt Flag 2
RESET:
Bit 7
TOF
0
6
RTIF
0
$0025
5
PAOVF
0
4
PAIF
0
3
0
0
2
0
0
1
0
0
Bit 0
0
0
Clear flags by writing a one to the corresponding bit position(s).
TOF — Timer Overflow Interrupt Flag
Set when TCNT changes from $FFFF to $0000
Freescale Semiconductor, Inc...
RTIF — Real-Time Interrupt Flag
The RTIF status bit is automatically set to one at the end of every RTI period. To clear
RTIF, write a byte to TFLG2 with bit 6 set.
PAOVF — Pulse Accumulator Overflow Interrupt Flag
Refer to 9.6 Pulse Accumulator.
PAIF — Pulse Accumulator Input Edge Interrupt Flag
Refer to 9.6 Pulse Accumulator.
Bits [3:0] — Not implemented
Always read zero
9.4.2 Pulse Accumulator Control Register
Bits RTR[1:0] of this register select the rate for the real-time interrupt system. Bit
DDRA3 determines whether Port A bit three is an input or an output when used for
general-purpose I/O. The remaining bits control the pulse accumulator.
PACTL — Pulse Accumulator Control
RESET:
Bit 7
DDRA7
0
6
PAEN
0
5
PAMOD
0
$0026
4
PEDGE
0
3
DDRA3
0
2
I4/O5
0
1
RTR1
0
Bit 0
RTR0
0
DDRA7 — Data Direction Control for Port A Bit 7
Refer to 9.6 Pulse Accumulator.
PAEN — Pulse Accumulator System Enable
Refer to 9.6 Pulse Accumulator.
PAMOD — Pulse Accumulator Mode
Refer to 9.6 Pulse Accumulator.
PEDGE — Pulse Accumulator Edge Control
Refer to 9.6 Pulse Accumulator.
DDRA3 — Data Direction Register for Port A Bit 3
Refer to SECTION 6 PARALLEL I/O.
I4/O5 — Input Capture 4/Output Compare 5
Refer to 9.2 Input Capture.
TIMING SYSTEM
9-14
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RTR[1:0] — RTI Interrupt Rate Select
These two bits determine the rate at which the RTI system requests interrupts. The
RTI system is driven by an E divided by 213 rate clock that is compensated so it is independent of the timer prescaler. These two control bits select an additional division
factor.
Freescale Semiconductor, Inc...
RTR[1:0]
00
01
10
11
E = 1 MHz
2.731 ms
5.461 ms
10.923 ms
21.845 ms
E = 2 MHz
4.096 ms
8.192 ms
16.384 ms
32.768 ms
E = 3 MHz
8.192 ms
16.384 ms
32.768 ms
65.536 ms
E = X MHz
(E/213)
(E/214)
(E/215)
(E/216)
9.5 Computer Operating Properly Watchdog Function
The clocking chain for the COP function, tapped off of the main timer divider chain, is
only superficially related to the main timer system. The CR[1:0] bits in the OPTION
register and the NOCOP bit in the CONFIG register determine the status of the COP
function. Refer to SECTION 5 RESETS AND INTERRUPTS for a more detailed discussion of the COP function.
9.6 Pulse Accumulator
The MC68HC11D3 has an 8-bit counter that can be configured to operate either as a
simple event counter, or for gated time accumulation, depending on the state of the
PAMOD bit in the PACTL register. Refer to the pulse accumulator block diagram, Figure 9-3.
In the event counting mode, the 8-bit counter is clocked to increasing values by an external pin. The maximum clocking rate for the external event counting mode is the E
clock divided by two. In gated time accumulation mode, a free-running E-clock ÷ 64
signal drives the 8-bit counter, but only while the external PAI pin is activated. Refer to
Table 9-3. The pulse accumulator counter can be read or written at any time.
TIMING SYSTEM
TECHNICAL DATA
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1
INTERRUPT
REQUESTS
TMSK2
PAIF
PAOVF
PAII
PAOVI
2
TFLG2
PAI EDGE
DISABLE
FLAG SETTING
INPUT BUFFER
&
EDGE DETECTION
PA7/
PAI/OC1
OVERFLOW
2:1
MUX
PACNT
8-BIT COUNTER
ENABLE
OUTPUT
BUFFER
PEDGE
PAMOD
PAEN
PAEN
FROM
MAIN TIMER
OC1
DDRA7
Freescale Semiconductor, Inc...
E ÷ 64 CLOCK
(FROM MAIN TIMER)
PACTL
INTERNAL
DATA BUS
11 PULSE ACC BLOCK
Figure 9-3 Pulse Accumulator
Table 9-3 Pulse Accumulator Timing
Common XTAL Frequencies
Selected Crystal
CPU Clock
(E)
Cycle Time
(1/E)
Pulse Accumulator (in Gated Mode)
1 count (E/26)
overflow (E/214)
4.0 MHz
1.0 MHz
1000 ns
8.0 MHz
2.0 MHz
500 ns
12.0 MHz
3.0 MHz
333 ns
64.0 µs
16.384 ms
32.0 µs
8.192 ms
21.33 µs
5.461 ms
Pulse accumulator control bits are also located within two timer registers, TMSK2 and
TFLG2, as described in the following paragraphs.
TIMING SYSTEM
9-16
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9.6.1 Pulse Accumulator Control Register
Four of this register's bits control an 8-bit pulse accumulator system. Another bit enables either the OC5 function or the IC4 function, while two other bits select the rate
for the real-time interrupt system.
PACTL — Pulse Accumulator Control
Freescale Semiconductor, Inc...
RESET:
Bit 7
DDRA7
0
6
PAEN
0
5
PAMOD
0
$0026
4
PEDGE
0
3
DDRA3
0
2
I4/O5
0
1
RTR1
0
Bit 0
RTR0
0
DDRA7 — Data Direction Control for Port A Bit 7
The pulse accumulator uses port A bit 7 as the PAI input, but the pin can also be used
as general-purpose I/O or as an output compare. Note that even when port A bit 7 is
configured as an output, the pin still drives the input to the pulse accumulator. Refer to
SECTION 6 PARALLEL I/O for more information.
PAEN — Pulse Accumulator System Enable
0 = Pulse accumulator disabled
1 = Pulse accumulator enabled
PAMOD — Pulse Accumulator Mode
0 = Event counter
1 = Gated time accumulation
PEDGE — Pulse Accumulator Edge Control
This bit has different meanings depending on the state of the PAMOD bit, as shown in
the following table:
PAMOD
0
0
1
1
PEDGE
0
1
0
1
Action on Clock
PAI Falling Edge Increments the Counter.
PAI Rising Edge Increments the Counter.
A Zero on PAI Inhibits Counting.
A One on PAI Inhibits Counting.
DDRA3 — Data Direction Register for Port A Bit 3
Refer to SECTION 6 PARALLEL I/O.
I4/O5 — Input Capture 4/Output Compare 5
Refer to 9.2 Input Capture.
RTR[1:0] — RTI Interrupt Rate Selects
Refer to 9.4 Real-Time Interrupt.
9.6.2 Pulse Accumulator Count Register
This 8-bit read/write register contains the count of external input events at the PAI input, or the accumulated count. The counter is not affected by reset and can be read or
written at any time. Counting is synchronized to the internal PH2 clock so that incrementing and reading occur during opposite half cycles.
TIMING SYSTEM
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PACNT — Pulse Accumulator Count
Bit 7
Bit 7
6
6
5
5
$0027
4
4
3
3
2
2
1
1
Bit 0
Bit 0
Freescale Semiconductor, Inc...
9.6.3 Pulse Accumulator Status and Interrupt Bits
The pulse accumulator control bits, PAOVI and PAII, PAOVF, and PAIF are located
within timer registers TMSK2 and TFLG2.
PAOVI and PAOVF — Pulse Accumulator Interrupt Enable and Overflow Flag
The PAOVF status bit is set each time the pulse accumulator count rolls over from $FF
to $00. To clear this status bit, write a one in the corresponding data bit position (bit 5)
of the TFLG2 register. The PAOVI control bit allows configuring the pulse accumulator
overflow for polled or interrupt-driven operation and does not affect the state of
PAOVF. When PAOVI is zero, pulse accumulator overflow interrupts are inhibited, and
the system operates in a polled mode, which requires PAOVF to be polled by user software to determine when an overflow has occurred. When the PAOVI control bit is set,
a hardware interrupt request is generated each time PAOVF is set. Before leaving the
interrupt service routine, software must clear PAOVF by writing to the TFLG2 register.
PAII and PAIF — Pulse Accumulator Input Edge Interrupt Enable and Flag
The PAIF status bit is automatically set each time a selected edge is detected at the
PA7/PAI/OC1 pin. To clear this status bit, write to the TFLG2 register with a one in the
corresponding data bit position (bit 4). The PAII control bit allows configuring the pulse
accumulator input edge detect for polled or interrupt-driven operation but does not affect setting or clearing the PAIF bit. When PAII is zero, pulse accumulator input interrupts are inhibited, and the system operates in a polled mode. In this mode, the PAIF
bit must be polled by user software to determine when an edge has occurred. When
the PAII control bit is set, a hardware interrupt request is generated each time PAIF is
set. Before leaving the interrupt service routine, software must clear PAIF by writing to
the TFLG register.
TMSK2 — Timer Interrupt Mask 2
RESET:
Bit 7
TOI
0
6
RTII
0
$0024
5
PAOVI
0
4
PAII
0
3
0
0
2
0
0
1
PR1
0
TFLG2 — Timer Interrupt Flag 2
RESET:
Bit 7
TOF
0
6
RTIF
0
Bit 0
PR0
0
$0025
5
PAOVF
0
4
PAIF
0
3
0
0
2
0
0
1
0
0
Bit 0
0
0
TIMING SYSTEM
9-18
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APPENDIX A
ELECTRICAL CHARACTERISTICS
Table A-1 Maximum Ratings
Freescale Semiconductor, Inc...
Rating
Symbol
Value
Unit
Supply Voltage
VDD
– 0.3 to + 7.0
V
Input Voltage
Vin
– 0.3 to + 7.0
V
Operating Temperature Range
MC6811D3
MC6811D3C
MC6811D3V
MC6811D3M
TA
TL to TH
°C
0 to + 70
– 40 to + 85
– 40 to + 105
– 40 to + 125
Storage Temperature Range
Tstg
– 55 to + 150
°C
ID
25
mA
Current Drain per Pin*
Excluding VDD and VSS
*One pin at a time, observing maximum power dissipation limits.
Internal circuitry protects the inputs against damage caused by high static voltages or
electric fields; however, normal precautions are necessary to avoid application of any
voltage higher than maximum-rated voltages to this high-impedance circuit. Extended
operation at the maximum ratings can adversely affect device reliability. Tying unused
inputs to an appropriate logic voltage level (either GND or VDD) enhances reliability of
operation.
Table A-2 Thermal Characteristics
Symbol
Value
Unit
Average Junction Temperature
Characteristic
TJ
TA + (PD x ΘJA)
°C
Ambient Temperature
TA
User-determined
°C
Package Thermal Resistance
(Junction-to-Ambient)
44-Pin Plastic Leaded Chip Carrier (PLCC)
44-Pin Plastic Quad Flat Pack (QFP)
52-Pin Plastic Dip (P)
ΘJA
Total Power Dissipation
PD
(Note 1)
°C/W
50
50
50
PINT + PI/O
K / (TJ + 273°C)
W
PINT
IDD x VDD
W
I/O Pin Power Dissipation
(Note 2)
PI/O
User-determined
W
A Constant
(Note 3)
K
PD x (TA + 273°C) +
ΘJA x PD2
W < °C
Device Internal Power Dissipation
NOTES:
1. This is an approximate value, neglecting PI/O.
2. For most applications PI/O « PINT and can be neglected.
3. K is a constant pertaining to the device. Solve for K with a known TA and a measured PD (at equilibrium). Use
this value of K to solve for P D and TJ iteratively for any value of TA.
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-1
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Table A-3 DC Electrical Characteristics
Characteristic
Symbol
Min
Max
Unit
All Outputs except XTAL
All Outputs Except XTAL, RESET,
and MODA
VOL
VOH
—
VDD – 0.1
0.1
—
V
V
All Outputs Except XTAL,
RESET, and MODA
VOH
VDD – 0.8
—
V
Output Low Voltage
ILOAD = 1.6 mA, VDD = 5.0 V
All Outputs Except XTAL
VOL
—
0.4
V
Input High Voltage
All Inputs Except RESET
RESET
VIH
0.7 x VDD
0.8 x VDD
VDD + 0.3
VDD + 0.3
V
V
Input Low Voltage
All Inputs
VIL
VSS – 0.3
0.2 x VDD
V
I/O Ports, Three-State Leakage PA7, PA3, PB[7:0], PC[7:0], PD[7:0],
MODA/LIR, RESET
Vin = VIH or VIL
IOZ
—
±10
µA
Input Leakage Current
Vin = VDD or VSS
Vin = VDD or VSS
PA[2:0], IRQ, XIRQ
MODB/VSTBY
Iin
—
—
±1
±10
µA
µA
RAM Standby Voltage
Power down
VSB
4.0
VDD
V
RAM Standby Current
Power down
ISB
—
10
µA
Input Capacitance
PA[2:0], IRQ, XIRQ, EXTAL
PA7, PA3, PB[7:0], PC[7:0], PD[7:0], MODA/LIR, RESET
Cin
—
—
8
12
pF
pF
Output Load Capacitance
All Outputs Except PD[4:1]
CL
—
—
90
100
pF
pF
Symbol
1 MHz
2 MHz
Unit
8
14
15
27
mA
mA
3
5
6
10
mA
mA
50
50
µA
44
77
85
150
mW
mW
Output Voltage (Note 1)
ILOAD = ± 10.0 µA
Output High Voltage (Note 1)
Freescale Semiconductor, Inc...
ILOAD = – 0.8 mA, VDD = 4.5 V
PD[4:1]
Characteristic
Maximum Total Supply Current (Note 2)
RUN:
Single-Chip Mode
VDD = 5.5 V
Expanded Multiplexed Mode
VDD = 5.5 V
(All Peripheral Functions Shut Down)
WAIT:
Single-Chip Mode
VDD = 5.5 V
Expanded Multiplexed Mode
VDD = 5.5 V
STOP:
Single-Chip Mode, No Clocks
VDD = 5.5 V
Maximum Power Dissipation
Single-Chip Mode
Expanded Multiplexed Mode
VDD = 5.5 V
VDD = 5.5 V
IDD
WIDD
SIDD
PD
NOTES:
1. VOH specification for RESET and MODA is not applicable because they are open-drain pins. VOH specification
not applicable to ports C and D in wired-OR mode.
2. EXTAL is driven with a square wave, and
tcyc = 1000 ns for 1 MHz rating;
tcyc = 500 ns for 2 MHz rating;
tcyc = 333 ns for 3 MHz rating;
VIL ≤ 0.2 V;VIH ≥ VDD - 0.2 V;
No dc loads.
ELECTRICAL CHARACTERISTICS
A-2
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TECHNICAL DATA
Freescale Semiconductor, Inc.
~ VDD
CLOCKS,
STROBES
VDD– 0.8 Volts
0.4 Volts
0.4 Volts
~ V SS
NOM.
NOM.
70% of VDD
INPUTS
20% of VDD
NOMINAL TIMING
~ VDD
VDD– 0.8 Volts
OUTPUTS
0.4 Volts
~ VSS
Freescale Semiconductor, Inc...
DC TESTING
~ VDD
CLOCKS,
STROBES
70% of VDD
20% of VDD
~ V SS
20% of VDD
SPEC
SPEC
70% of VDD
INPUTS
20% of VDD
(NOTE 2)
VDD – 0.8 Volts
0.4 Volts
SPEC TIMING
~ VDD
OUTPUTS
~ VSS
70% of VDD
20% of VDD
AC TESTING
NOTES:
1. Full test loads are applied during all DC electrical tests and AC timing measurements.
2. During AC timing measurements, inputs are driven to 0.4 volts and VDD – 0.8 volts while timing
measurements are taken at the 20% and 70% of VDD points.
TEST METHODS
Figure A-1 Test Methods
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-3
Freescale Semiconductor, Inc.
Table A-4 Control Timing
Characteristic
Symbol
Frequency of Operation
E-Clock Period
Crystal Frequency
2.0 MHz
3.0 MHz
Unit
Min
Max
Min
Max
Min
Max
fo
dc
1.0
dc
2.0
dc
3.0
MHz
tcyc
1000
—
500
—
333
—
ns
fXTAL
—
4.0
—
8.0
—
12.0
MHz
External Oscillator Frequency
4 fo
dc
4.0
dc
8.0
dc
12.0
MHz
Processor Control SetupTime
tPCSU = 1/4 tcyc + 50 ns
tPCSU
300
—
175
—
133
—
ns
8
1
—
—
8
1
—
—
8
1
—
—
tcyc
tcyc
Reset Input Pulse Width
To Guarantee External Reset Vector
Minimum Input Time
(Can Be Preempted by Internal Reset)
Freescale Semiconductor, Inc...
1.0 MHz
PWRSTL
Mode Programming Setup Time
tMPS
2
—
2
—
2
—
tcyc
Mode Programming Hold Time
tMPH
10
—
10
—
10
—
ns
Interrupt Pulse Width,
IRQ Edge-Sensitive Mode
PWIRQ = tcyc + 20 ns
PWIRQ
1020
—
520
—
353
—
ns
Wait Recovery Startup Time
tWRS
—
4
—
4
—
4
tcyc
PWTIM
1020
—
520
—
353
—
ns
Timer Pulse Width,
Input Capture Pulse
Accumulator Input
PWTIM = tcyc + 20 ns
NOTES:
1. RESET is recognized during the first clock cycle it is held low. Internal circuitry then drives the pin low for four
clock cycles, releases the pin, and samples the pin level two cycles later to determine the source of the interrupt.
Refer to SECTION 5 RESETS AND INTERRUPTS for further detail.
2. All timing is shown with respect to 20% V DD and 70% VDD, unless otherwise noted.
PA[2:0]
PA[2:0]
PA7
1
2
1,3
PWTIM
PA7
2,3
NOTES:
1. Rising edge sensitive input
2. Falling edge sensitive input
3. Maximum pulse accumulator clocking rate is E-clock frequency divided by 2.
TIMER INPUTS TIM
Figure A-2 Timer Inputs
ELECTRICAL CHARACTERISTICS
A-4
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TECHNICAL DATA
POR EXT RESET TIM
FFFE
ADDRESS
MODA, MODB
RESET
E
EXTAL
VDD
4064 tCYC
FFFE
FFFE
FFFE
FFFE
FFFF
tPCSU
NEW
PC
FFFE
PWRSTL
tMPS
Freescale Semiconductor, Inc...
FFFE
tMPH
FFFE
FFFE
FFFF
NEW
PC
Freescale Semiconductor, Inc.
Figure A-3 POR and External Reset Timing Diagram
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-5
A-6
STOP
ADDR + 1
STOP
ADDR
ADDRESS5
PWIRQ
tSTOPDELAY3
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4. XIRQ with X bit in CCR = 1.
5. IRQ or (XIRQ with X bit in CCR = 0).
1. Edge Sensitive IRQ pin (IRQE bit = 1)
2. Level sensitive IRQ pin (IRQE bit = 0)
3. tSTOPDELAY
= 4064 tCYC if DLY bit = 1 or 4 tCYC if DLY = 0.
NOTES:
STOP
ADDR + 1
STOP
ADDR
ADDRESS4
E
IRQ
or XIRQ
IRQ1
INTERNAL
CLOCKS
STOP
STOP
SP…SP–7
ADDR + 1 ADDR + 2
SP – 8
SP – 8
FFF2
(FFF4)
FFF3
(FFF5)
STOP RECOVERY TIM
NEW
PC
Resume program with instruction which follows the STOP instruction.
STOP
OPCODE
ADDR + 1
Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
Figure A-4 STOP Recovery Timing Diagram
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
TECHNICAL DATA
WAIT
ADDR
WAIT
ADDR + 1
PCL
SP
SP – 2…SP – 8
STACK REGISTERS
PCH, YL, YH, XL, XH, A, B, CCR
SP – 1
NOTE: RESET also causes recovery from WAIT.
R/W
ADDRESS
IRQ, XIRQ,
OR INTERNAL
INTERRUPTS
E
SP – 8
SP – 8…SP – 8
SP – 8
tPCSU
SP – 8
tWRS
Freescale Semiconductor, Inc...
SP – 8
VECTOR
ADDR
VECTOR
ADDR + 1
WAIT RECOVERY TIM
NEW
PC
Freescale Semiconductor, Inc.
Figure A-5 WAIT Recovery Timing Diagram
ELECTRICAL CHARACTERISTICS
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A-7
Freescale Semiconductor, Inc.
Table A-5 Peripheral Port Timing
Characteristic
Symbol
2.0 MHz
3.0 MHz
Unit
Min
Max
Min
Max
Min
Max
fo
dc
1.0
dc
2.0
dc
3.0
MHz
tcyc
1000
—
500
—
333
—
ns
Peripheral Data Setup Time
MCU Read of Ports A, B, C, and D
tPDSU
100
—
100
—
100
—
ns
Peripheral Data Hold Time
MCU Read of Ports A, B, C, and D
tPDH
50
—
50
—
50
—
ns
Delay Time, Peripheral Data Write
tPWD
—
—
200
350
—
—
200
225
—
—
200
183
ns
ns
Frequency of Operation (E-Clock Frequency)
E-Clock Period
Freescale Semiconductor, Inc...
1.0 MHz
MCU Write to Port A
MCU Writes to Ports B, C, and D
tPWD = 1/4 tcyc + 150 ns
NOTES:
1. Port C and D timing is valid for active drive (CWOM and DWOM bits not set in PIOC and SPCR registers respectively).
2. All timing is shown with respect to 20% VDD and 70% VDD, unless otherwise noted.
MCU WRITE TO PORT
E
t PWD
PORTS
B, C, D
PREVIOUS PORT DATA
NEW DATA VALID
tPWD
PORT A
PREVIOUS PORT DATA
NEW DATA VALID
D3 PORT WRITE TIM
Figure A-6 Port Write Timing Diagram
MCU READ OF PORT
E
tPDSU
tPDH
PORTS
A, B, C, D
D3 PORT READ TIM
Figure A-7 Port Read Timing Diagram
ELECTRICAL CHARACTERISTICS
A-8
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TECHNICAL DATA
Freescale Semiconductor, Inc.
Table A-6 Expansion Bus Timing
Num
Characteristic
Symbol
Frequency of Operation (E-Clock
Frequency)
2.0 MHz
3.0 MHz
Unit
Min
Max
Min
Max
Min
Max
fo
dc
1.0
dc
2.0
dc
3.0
MHz
tcyc
1000
—
500
—
333
—
ns
1
Cycle Time
2
Pulse Width, E Low
PWEL = 1/2 tcyc - 23ns
PWEL
477
—
227
—
146
—
ns
3
Pulse Width, E High
PWEH = 1/2 tcyc - 28 ns
PWEH
472
—
222
—
141
—
ns
tr
tf
—
—
20
20
—
—
20
20
—
—
20
15
ns
ns
tAH
95.5
—
33
—
26
—
ns
tAV
281.5
—
94
—
54
—
ns
4A
4B
9
Freescale Semiconductor, Inc...
1.0 MHz
E and AS Rise Time
E and AS Fall Time
Address Hold Time
tAH = 1/8 tcyc - 29.5 ns
(Note 1a)
12
Non-Muxed Address Valid Time to E Rise
tAV = PWEL - (tASD + 80 ns) (Note 1a)
17
Read Data Setup Time
tDSR
30
—
30
—
30
—
ns
18
Read Data Hold Time (Max = tMAD)
tDHR
0
145.5
0
83
0
51
ns
19
Write Data Delay Time
tDDW = 1/8 tcyc + 65.5 ns
tDDW
—
190.5
—
128
—
71
ns
(Note 1a)
Write Data Hold Time
tDHW = 1/8 tcyc - 30 ns
tDHW
95.5
—
33
—
26
—
ns
(Note 1a)
21
22
Muxed Address Valid Time to E Rise
tAVM = PWEL - (tASD + 90 ns) (Note 1a)
tAVM
271.5
—
84
—
54
—
ns
24
Muxed Address Valid Time to AS Fall
tASL = PWASH - 70 ns
tASL
151
—
26
—
13
—
ns
25
Muxed Address Hold Time
tAHL = 1/8 tcyc - 30 ns
tAHL
95.5
—
33
—
31
—
ns
(Note 1b)
Delay Time, E to AS Rise
tASD = 1/8 tcyc - 5 ns
tASD
115.5
—
53
—
31
—
ns
(Note 1a)
PWASH
221
—
96
—
63
—
ns
tASED
115.5
—
53
—
31
—
ns
26
27
Pulse Width, AS High
PWASH = 1/4 tcyc - 30 ns
28
Delay Time, AS to E Rise
tASED = 1/8 tcyc - 5 ns
(Note 1b)
29
MPU Address Access Time
(Note 1a)
tACCA = tcyc – (PWEL– tAVM) – tDSR–tf
tACCA
744.5
—
307
—
196
—
ns
35
MPU Access Time
tACCE = PWEH - tDSR
tACCE
—
442
—
192
—
111
ns
36
Muxed Address Delay
(Previous Cycle MPU Read)
tMAD = tASD + 30 ns(Note 1a)
tMAD
145.5
—
83
—
51
—
ns
NOTES:
1. Input clocks with duty cycles other than 50% affect bus performance. Timing parameters affected by input clock
duty cycle are identified by (a) and (b). To recalculate the approximate bus timing values, substitute the following
expressions in place of 1/8 tcyc in the above formulas, where applicable:
(a) (1-DC) × 1/4 tcyc
(b) DC × 1/4 tcyc
Where:
DC is the decimal value of duty cycle percentage (high time).
2. All timing is shown with respect to 20% VDD and 70% VDD, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-9
Freescale Semiconductor, Inc.
1
2
3
E
4a
4b
12
9
R/W, ADDRESS
(NON-MUX)
22
35
17
36
29
READ
ADDRESS
DATA
ADDRESS/DATA
(MULTIPLEXED)
Freescale Semiconductor, Inc...
18
19
WRITE
ADDRESS
21
DATA
25
24
4a
4b
AS
26
27
28
NOTE: Measurement points shown are 20% and 70% of VDD.
MUX BUS TIM
Figure A-8 Multiplexed Expansion Bus Timing Diagram
ELECTRICAL CHARACTERISTICS
A-10
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TECHNICAL DATA
Freescale Semiconductor, Inc.
Table A-7 Serial Peripheral Interface Timing
Num
Characteristic
2.0 MHz
3.0 MHz
Unit
Min
Max
Min
Max
fop(m)
fop(s)
dc
dc
0.5
2.0
dc
dc
0.5
3.0
fop
MHz
Cycle Time
Master
Slave
tcyc(m)
tcyc(s)
2.0
500
—
—
2.0
333
—
—
tcyc
ns
Enable Lead Time
Master (Note 2)
Slave
tlead(m)
tlead(s)
—
250
—
—
—
240
—
—
ns
ns
Enable Lag Time
Master (Note 2)
Slave
tlag(m)
tlag(s)
—
250
—
—
—
240
—
—
ns
ns
Clock (SCK) High Time
Master
Slave
tw(SCKH)m
tw(SCKH)s
340
190
—
—
340
190
—
—
ns
ns
Clock (SCK) Low Time
Master
Slave
tw(SCKL)m
tw(SCKL)s
340
190
—
—
340
190
—
—
ns
ns
Data Setup Time (Inputs)
Master
Slave
tsu(m)
tsu(s)
100
100
—
—
100
100
—
—
ns
ns
Data Hold Time (Inputs)
Master
Slave
th(m)
th(s)
100
100
—
—
100
100
—
—
ns
ns
Access Time
(Time to Data Active from High-Imp. State)
Slave
ta
0
120
0
120
ns
Disable Time
(Hold Time to High-Impedance State)
Slave
tdis
—
240
—
167
ns
10
Data Valid (After Enable Edge) (Note 3)
tv(s)
—
240
—
167
ns
11
Data Hold Time (Outputs) (After Enable Edge)
tho
0
—
0
—
ns
12
Rise Time (20% VDD to 70% VDD, CL = 200 pF)
SPI Outputs (SCK, MOSI, and MISO)
SPI Inputs (SCK, MOSI, MISO, and SS)
trm
trs
—
—
100
2.0
—
—
100
2.0
ns
µs
Fall Time (70% VDD to 20% VDD, CL = 200 pF)
SPI Outputs (SCK, MOSI, and MISO)
SPI Inputs (SCK, MOSI, MISO, and SS)
tfm
tfs
—
—
100
2.0
—
—
100
2.0
ns
µs
Operating Frequency
Master
Slave
1
2
3
Freescale Semiconductor, Inc...
Symbol
4
5
6
7
8
9
13
NOTES:
1. All timing is shown with respect to 20% VDD and 70% VDD, unless otherwise noted.
2. Signal production depends on software.
3. Assumes 100 pF load on all SPI pins.
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-11
Freescale Semiconductor, Inc.
SS
(INPUT)
SS is held high on master.
1
12
13
13
12
5
SCK (CPOL = 0)
(OUTPUT)
SEE
NOTE
4
5
SCK (CPOL = 1)
(OUTPUT)
SEE
NOTE
4
6
MISO
(INPUT)
7
MSB IN
BIT 6 - - - -1
11
Freescale Semiconductor, Inc...
10 (ref)
MOSI
(OUTPUT)
MASTER MSB OUT
LSB IN
11 (ref)
10
BIT 6 - - - -1
MASTER LSB OUT
13
12
NOTE: This first clock edge is generated internally but is not seen at the SCK pin.
SPI MASTER CPHA0 TIM
Figure A-9 SPI Master Timing (CPHA = 0)
SS
(INPUT)
SS is held high on master.
1
12
13
5
SEE
NOTE
SCK (CPOL = 0)
(OUTPUT)
4
13
5
SCK (CPOL = 1)
(OUTPUT)
SEE
NOTE
4
MISO
(INPUT)
MSB IN
10 (ref)
MOSI
(OUTPUT)
12
BIT 6 - - - -1
LSB IN
11 (ref)
10
11
MASTER MSB OUT
7
6
BIT 6 - - - -1
MASTER LSB OUT
13
NOTE: This last clock edge is generated internally but is not seen at the SCK pin.
12
SPI MASTER CPHA1 TIM
Figure A-10 SPI Master Timing (CPHA = 1)
ELECTRICAL CHARACTERISTICS
A-12
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TECHNICAL DATA
Freescale Semiconductor, Inc.
SS
(INPUT)
1
13
12
12
13
3
5
SCK (CPOL = 0)
(INPUT)
4
2
5
SCK (CPOL = 1)
(INPUT)
4
8
MISO
(OUTPUT)
Freescale Semiconductor, Inc...
6
MOSI
(INPUT)
BIT 6 - - - -1
MSB OUT
SLAVE
7
10
SEE
NOTE
SLAVE LSB OUT
11
11
BIT 6 - - - -1
MSB IN
9
LSB IN
NOTE: Not defined but normally MSB of character just received.
SPI SLAVE CPHA0 TIM
Figure A-11 SPI Slave Timing (CPHA = 0)
SS
(INPUT)
1
12
13
5
SCK (CPOL = 0)
(INPUT)
4
2
3
5
SCK (CPOL = 1)
(INPUT)
4
8
MISO
(OUTPUT)
SEE
NOTE
SLAVE
MSB OUT
6
MOSI
(INPUT)
13
10
7
MSB IN
12
BIT 6 - - - -1
10
9
SLAVE LSB OUT
11
BIT 6 - - - -1
LSB IN
NOTE: Not defined but normally LSB of character previously transmitted.
SPI SLAVE CPHA1 TIM
Figure A-12 SPI Slave Timing (CPHA = 1)
ELECTRICAL CHARACTERISTICS
TECHNICAL DATA
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A-13
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Freescale Semiconductor, Inc.
ELECTRICAL CHARACTERISTICS
A-14
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TECHNICAL DATA
Freescale Semiconductor, Inc.
APPENDIX B
MECHANICAL DATA AND ORDERING INFORMATION
Freescale Semiconductor, Inc...
B.1 Pin Assignments
The MC68HC11D3 is available in the 40-pin DIP, shown in Figure B-1, the 44-pin
PLCC, shown in Figure B-2, or the 44-pin quad flat pack (QFP), as shown in Figure
B-3. Refer to Table B-1 for ordering information.
VSS
1
40
XTAL
PC0/ADDR0
2
39
EXTAL
PC1/ADDR1
3
38
E
PC2/ADDR2
4
37
MODA/LIR
PC3/ADDR3
5
36
MODB/VSTBY
PC4/ADDR4
6
35
PB0/ADDR8
PC5/ADDR5
7
34
PB1/ADDR9
PC6/ADDR6
8
33
PB2/ADDR10
PC7/ADDR7
MC68HC(7)11D3
9
32
PB3/ADDR11
XIRQ/VPP
10
31
PB4/ADDR12
PD7/R/W
11
30
PB5/ADDR13
PD6/AS
12
29
PB6/ADDR14
RESET
13
28
PB7/ADDR15
IRQ
14
27
PA0/IC3
PD0/RxD
15
26
PA1/IC2
PD1/TxD
16
25
PA2/IC1
PD2/MISO
17
24
PA3/IC4/OC5/OC1
PD3/MOSI
18
23
PA5/OC3/OC1
PD4/SCK
19
22
PA7/PAI/OC1
PD5/SS
20
21
VDD
D3 40-PIN DIP
Figure B-1 40-Pin DIP
MECHANICAL DATA AND ORDERING INFORMATION
TECHNICAL DATA
For More Information On This Product,
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B-1
E
MODA/LIR
MODB/VSTBY
42
41
40
EXTAL
VSS
2
43
PC0/ADDR0
3
XTAL
PC1/ADDR1
4
44
PC2/ADDR2
5
EVSS
PC3/ADDR3
6
1
39
PB0/ADDR8
PC4/ADDR4
7
PC5/ADDR5
8
38
PB1/ADDR9
PC6/ADDR6
9
37
PB2/ADDR10
PC7/ADDR7
10
36
PB3/ADDR11
XIRQ/VPP
11
35
PB4/ADDR12
PD7/R/W
12
34
PB5/ADDR13
PD6/AS
13
33
PB6/ADDR14
RESET
14
32
PB7/ADDR15
IRQ
15
31
NC
PD0/RxD
16
30
PA0/IC3
PD1/TxD
17
29
PA1/IC2
25
26
27
28
PA5/OC3/OC1
PA4/OC4/OC1
PA3/IC4/OC5/OC1
PA2/IC1
22
VDD
24
21
PD5/SS
PA6/OC2/OC1
20
PD4/SCK
23
19
PD3/MOSI
PA7/PAI/OC1
18
PD2/MISO
MC68HC(7)11D3
Figure B-2 44-Pin PLCC
Freescale Semiconductor, nc...
I
MC68HC11D3
B-2
TECHNICAL DATA
PC0/ADDR0
VSS
EVSS
XTAL
EXTAL
E
MODA/LIR
40
39
38
36
35
34
MODB/VSTBY
PC1/ADDR1
41
37
PC2/ADDR2
42
PC3/ADDR3
44
43
PC4/ADDR4
PB0/ADDR8
PC5/ADDR5
1
2
33
32
PC6/ADDR6
3
31
PB2/ADDR10
PC7/ADDR7
4
30
PB3/ADDR11
XIRQ/VPP
5
29
PB4/ADDR12
PD7/R/W
6
28
PB5/ADDR13
PD6/AS
7
27
PB6/ADDR14
RESET
8
26
PB7/ADDR15
IRQ
9
25
NC
PD0/RxD
10
PA0/IC3
PD1/TxD
11
24
23
13
14
15
16
17
18
19
20
21
22
PD3/MOSI
PD4/SCK
PD5/SS
VDD
PA7/PAI/OC1
PA6/OC2/OC1
PA5/OC3/OC1
PA4/OC4/OC1
PA3/IC4/OC5/OC1
PA1/IC2
PA2/IC1
12
PD2/MISO
MC68HC(7)11D3
PB1/ADDR9
Figure B-3 44-Pin QFP
B.2 Package Dimensions
For case outline information check our web site at http://www.motsps.com.
B.3 Ordering Information
Add the proper suffix, from Table B-1, to the M68HC11- (or 711-) MCU number to
specify the appropriate device when placing an order. Figure B-4 identifies the codes
used to identify specific MCU options.
Table B-1 Ordering Information
Package
40-Pin DIP
44-Pin PLCC
44-Pin Quad Flat Pack
40-Pin DIP
44-Pin PLCC
44-Pin Quad Flat Pack
MCU
D3
D0
Temperature
– 40 to +85°C
– 40 to +85°C
– 40 to +85°C
– 40 to +85°C
– 40 to +85°C
– 40 to +85°C
Description
BUFFALO ROM
BUFFALO ROM
BUFFALO ROM
No ROM
No ROM
No ROM
Suffix
CP1
CFN1
CFBL
CP
CFN
CFB
Freescale Semiconductor, nc...
I
TECHNICAL DATA
B-3
Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
Figure B-4 M68HC11 Part Number Options
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APPENDIX C
DEVELOPMENT SUPPORT
Freescale Semiconductor, Inc...
C.1 Development System Tools
Freescale has developed tools for use in debugging and evaluating M68HC11 equipment. Refer to the following list for those development tools that are available for use
with the MC68HC11D3. For information about Freescale and third party development
system hardware and software, contact your Freescale sales representative.
C.2 MC68HC11D3 Development Tools
• M68HC11D3EVS Evaluation System
• M68HC711D3PGMR Programmer Board
• M68HC711D3EVB Evaluation Board
DEVELOPMENT SUPPORT
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C-1
Freescale Semiconductor, Inc...
Freescale Semiconductor, Inc.
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DEVELOPMENT SUPPORT
C-2
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