PIC18F24J10 DATA SHEET (05/20/2009) DOWNLOAD

PIC18F45J10 Family
Data Sheet
28/40/44-Pin High-Performance,
RISC Microcontrollers
© 2009 Microchip Technology Inc.
DS39682E
Note the following details of the code protection feature on Microchip devices:
•
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•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
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•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
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Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
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Information contained in this publication regarding device
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Trademarks
The Microchip name and logo, the Microchip logo, Accuron,
dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro,
PICSTART, rfPIC, SmartShunt and UNI/O are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
FilterLab, Hampshire, Linear Active Thermistor, MXDEV,
MXLAB, SEEVAL, SmartSensor and The Embedded Control
Solutions Company are registered trademarks of Microchip
Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, In-Circuit Serial
Programming, ICSP, ICEPIC, Mindi, MiWi, MPASM, MPLAB
Certified logo, MPLIB, MPLINK, mTouch, nanoWatt XLP,
PICkit, PICDEM, PICDEM.net, PICtail, PIC32 logo, PowerCal,
PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, Select
Mode, Total Endurance, TSHARC, WiperLock and ZENA are
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2009, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS39682E-page ii
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
28/40/44-Pin High-Performance, RISC Microcontrollers
Special Microcontroller Features:
Peripheral Highlights:
•
•
•
•
• High-Current Sink/Source 25 mA/25 mA
(PORTB and PORTC)
• Three Programmable External Interrupts
• Four Input Change Interrupts
• One Capture/Compare/PWM (CCP) module
• One Enhanced Capture/Compare/PWM (ECCP)
module:
- One, two or four PWM outputs
- Selectable polarity
- Programmable dead time
- Auto-shutdown and auto-restart
• Two Master Synchronous Serial Port (MSSP)
modules supporting 3-Wire SPI (all 4 modes) and
I2C™ Master and Slave modes
• One Enhanced Addressable USART module:
- Supports RS-485, RS-232 and LIN/J2602
- Auto-wake-up on Start bit
- Auto-Baud Detect (ABD)
• 10-Bit, up to 13-Channel Analog-to-Digital
Converter module (A/D):
- Auto-acquisition capability
- Conversion available during Sleep
- Self-calibration feature
• Dual Analog Comparators with Input Multiplexing
•
•
Flexible Oscillator Structure:
•
•
•
•
•
•
Two Crystal modes, up to 40 MHz
Two External Clock modes, up to 40 MHz
Internal 31 kHz Oscillator
Secondary Oscillator using Timer1 @ 32 kHz
Two-Speed Oscillator Start-up
Fail-Safe Clock Monitor:
- Allows for safe shutdown if peripheral clock
stops
Program Memory
Device
MSSP
SRAM Data
Flash # Single-Word Memory
(bytes)
(bytes) Instructions
I/O
10-Bit
A/D (ch)
CCP/
ECCP
(PWM)
SPI
Master
I2C™
Timers
8/16-Bit
•
Comparators
•
•
•
EUSART
•
•
•
Operating Voltage Range: 2.0V to 3.6V
5.5V Tolerant Input (digital pins only)
On-Chip 2.5V Regulator
4x Phase Lock Loop (PLL) available for Crystal
and Internal Oscillators
Self-Programmable under Software Control
Low-Power, High-Speed CMOS Flash Technology
C Compiler Optimized Architecture:
- Optional extended instruction set designed to
optimize re-entrant code
Priority Levels for Interrupts
8 x 8 Single-Cycle Hardware Multiplier
Extended Watchdog Timer (WDT):
- Programmable period from 4 ms to 131s
Single-Supply In-Circuit Serial Programming™
(ICSP™) via Two Pins
In-Circuit Debug (ICD) with Three Breakpoints via
Two Pins
Power-Managed modes with Clock Switching:
- Run: CPU on, peripherals on
- Idle: CPU off, peripherals on
- Sleep: CPU off, peripherals off
PIC18F24J10
16K
8192
1024
21
10
2/0
1
Y
Y
1
2
1/2
PIC18F25J10
32K
16384
1024
21
10
2/0
1
Y
Y
1
2
1/2
PIC18F44J10
16K
8192
1024
32
13
1/1
2
Y
Y
1
2
1/2
PIC18F45J10
32K
16384
1024
32
13
1/1
2
Y
Y
1
2
1/2
© 2009 Microchip Technology Inc.
DS39682E-page 1
PIC18F45J10 FAMILY
Pin Diagrams
= Pins are up to 5.5V tolerant
MCLR
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
VDDCORE/VCAP
RA5/AN4/SS1/C2OUT
VSS
OSC1/CLKI
OSC2/CLKO
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2*
RC2/CCP1
RC3/SCK1/SCL1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
PIC18F24J10
PIC18F25J10
28-Pin SPDIP, SOIC, SSOP (300 MIL)
28
27
26
25
24
23
22
21
20
19
18
17
16
15
RB7/KBI3/PGD
RB6/KBI2/PGC
RB5/KBI1/T0CKI/C1OUT
RB4/KBI0/AN11
RB3/AN9/CCP2*
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RC7/RX/DT
RC6/TX/CK
RC5/SDO1
RC4/SDI1/SDA1
* Pin feature is dependent on device configuration.
.
28-Pin QFN
RA1/AN1
RA0/AN0
MCLR
RB7/KBI3/PGD
RB6/KBI2/PGC
RB5/KBI1/T0CKI/C1OUT
RB4/KBI0/AN11
= Pins are up to 5.5V tolerant
28 27 26 25 24 23 22
1
2
3
4
5
6
7
PIC18F24J10
PIC18F25J10
8 9 10 11 12 13 14
21
20
19
18
17
16
15
RB3/AN9/CCP2*
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RC7/RX/DT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2*
RC2/CCP1
RC3/SCK1/SCL1
RC4/SDI1/SDA1
RC5/SDO1
RC6/TX/CK
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
VDDCORE/VCAP
RA5/AN4/SS1/C2OUT
VSS
OSC1/CLKI
OSC2/CLKO
* Pin feature is dependent on device configuration.
DS39682E-page 2
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
Pin Diagrams (Continued)
= Pins are up to 5.5V tolerant
40-Pin PDIP (600 MIL)
1
40
2
39
3
38
4
37
5
36
6
35
7
34
8
9
10
11
12
13
PIC18F44J10
PIC18F45J10
MCLR
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
VDDCORE/VCAP
RA5/AN4/SS1/C2OUT
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
VDD
VSS
OSC1/CLKI
OSC2/CLKO
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2*
RC2/CCP1/P1A
RC3/SCK1/SCL1
RD0/PSP0/SCK2/SCL2
RD1/PSP1/SDI2/SDA2
RB7/KBI3/PGD
RB6/KBI2/PGC
RB5/KBI1/T0CKI/C1OUT
RB4/KBI0/AN11
RB3/AN9/CCP2*
RB2/INT2/AN8
RB1/INT1/AN10
RB0/INT0/FLT0/AN12
VDD
VSS
RD7/PSP7/P1D
RD6/PSP6/P1C
RD5/PSP5/P1B
RD4/PSP4
RC7/RX/DT
RC6/TX/CK
RC5/SDO1
RC4/SDI1/SDA1
RD3/PSP3/SS2
RD2/PSP2/SDO2
33
32
31
30
29
28
14
27
15
26
16
25
17
24
18
23
19
22
20
21
* Pin feature is dependent on device configuration.
.
44
43
42
41
40
39
38
37
36
35
34
PIC18F44J10
PIC18F45J10
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
OSC2/CLKO
OSC1/CLKI
VSS
VSS
VDD
VDD
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/AN4/SS1/C2OUT
VDDCORE/VCAP
RB3/AN9/CCP2*
NC
RB4/KBI0/AN11
RB5/KBI1/T0CKI/C1OUT
RB6/KBI2/PGC
RB7/KBI3/PGD
MCLR
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREFRA3/AN3/VREF+
RC7/RX/DT
RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
VSS
VDD
VDD
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
= Pins are up to 5.5V tolerant
RC6/TX/CK
RC5/SDO1
RC4/SDI1/SDA1
RD3/PSP3/SS2
RD2/PSP2/SDO2
RD1/PSP1/SDI2/SDA2
RD0/PSP0/SCK2/SCL2
RC3/SCK1/SCL1
RC2/CCP1/P1A
RC1/T1OSI/CCP2*
RC0/T1OSO/T1CKI
44-Pin QFN(1)
* Pin feature is dependent on device configuration.
Note 1: For the QFN package, it is recommended that the bottom pad be connected to VSS.
© 2009 Microchip Technology Inc.
DS39682E-page 3
PIC18F45J10 FAMILY
Pin Diagrams (Continued)
44-Pin TQFP
PIC18F44J10
PIC18F45J10
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
NC
RC0/T1OSO/T1CKI
OSC2/CLKO
OSC1/CLKI
VSS
VDD
RE2/CS/AN7
RE1/WR/AN6
RE0/RD/AN5
RA5/AN4/SS1/C2OUT
VDDCORE/VCAP
NC
NC
RB4/KBI0/AN11
RB5/KBI1/T0CKI/C1OUT
RB6/KBI2/PGC
RB7/KBI3/PGD
MCLR
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREFRA3/AN3/VREF+
RC7/RX/DT
RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
VSS
VDD
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2*
44
43
42
41
40
39
38
37
36
35
34
RC6/TX/CK
RC5/SDO1
RC4/SDI1/SDA1
RD3/PSP3/SS2
RD2/PSP2/SDO2
RD1/PSP1/SDI2/SDA2
RD0/PSP0/SCK2/SCL2
RC3/SCK1/SCL1
RC2/CCP1/P1A
RC1/T1OSI/CCP2*
NC
= Pins are up to 5.5V tolerant
* Pin feature is dependent on device configuration.
DS39682E-page 4
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
Table of Contents
1.0 Device Overview .......................................................................................................................................................................... 7
2.0 Guidelines for Getting Started with PIC18FJ Microcontrollers ................................................................................................... 23
3.0 Oscillator Configurations ............................................................................................................................................................ 27
4.0 Power-Managed Modes ............................................................................................................................................................. 35
5.0 Reset .......................................................................................................................................................................................... 41
6.0 Memory Organization ................................................................................................................................................................. 51
7.0 Flash Program Memory.............................................................................................................................................................. 71
8.0 8 x 8 Hardware Multiplier............................................................................................................................................................ 81
9.0 Interrupts .................................................................................................................................................................................... 83
10.0 I/O Ports ..................................................................................................................................................................................... 97
11.0 Timer0 Module ......................................................................................................................................................................... 115
12.0 Timer1 Module ......................................................................................................................................................................... 119
13.0 Timer2 Module ......................................................................................................................................................................... 125
14.0 Capture/Compare/PWM (CCP) Modules ................................................................................................................................. 127
15.0 Enhanced Capture/Compare/PWM (ECCP) Module................................................................................................................ 135
16.0 Master Synchronous Serial Port (MSSP) Module .................................................................................................................... 149
17.0 Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) ............................................................... 193
18.0 10-Bit Analog-to-Digital Converter (A/D) Module ..................................................................................................................... 215
19.0 Comparator Module.................................................................................................................................................................. 225
20.0 Comparator Voltage Reference Module................................................................................................................................... 231
21.0 Special Features of the CPU.................................................................................................................................................... 235
22.0 Instruction Set Summary .......................................................................................................................................................... 249
23.0 Development Support............................................................................................................................................................... 299
24.0 Electrical Characteristics .......................................................................................................................................................... 303
25.0 Packaging Information.............................................................................................................................................................. 337
Appendix A: Revision History............................................................................................................................................................. 349
Appendix B: Migration Between High-End Device Families............................................................................................................... 350
Index .................................................................................................................................................................................................. 353
The Microchip Web Site ..................................................................................................................................................................... 363
Customer Change Notification Service .............................................................................................................................................. 363
Customer Support .............................................................................................................................................................................. 363
Reader Response .............................................................................................................................................................................. 364
PIC18F45J10 family Product Identification System ........................................................................................................................... 365
© 2009 Microchip Technology Inc.
DS39682E-page 5
PIC18F45J10 FAMILY
TO OUR VALUED CUSTOMERS
It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip
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If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via
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welcome your feedback.
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The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
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To determine if an errata sheet exists for a particular device, please check with one of the following:
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DS39682E-page 6
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
1.0
DEVICE OVERVIEW
This document contains device specific information for
the following devices:
• PIC18F24J10
• PIC18LF24J10
• PIC18F25J10
• PIC18LF25J10
• PIC18F44J10
• PIC18LF44J10
• PIC18F45J10
• PIC18LF45J10
This family offers the advantages of all PIC18
microcontrollers – namely, high computational performance at an economical price. The PIC18F45J10 family
introduces design enhancements that make these microcontrollers a logical choice for many high-performance,
power sensitive applications.
1.1
1.1.1
Core Features
LOW POWER
All of the devices in the PIC18F45J10 family
incorporate a range of features that can significantly
reduce power consumption during operation. Key
items include:
• Alternate Run Modes: By clocking the controller
from the Timer1 source or the internal oscillator
block, power consumption during code execution
can be reduced by as much as 90%.
• Multiple Idle Modes: The controller can also run
with its CPU core disabled but the peripherals still
active. In these states, power consumption can be
reduced even further, to as little as 4% of normal
operation requirements.
• On-the-Fly Mode Switching: The powermanaged modes are invoked by user code during
operation, allowing the user to incorporate
power-saving ideas into their application’s software
design.
• Low Consumption in Key Modules: The
power requirements for both Timer1 and the
Watchdog Timer are minimized. See
Section 24.0 “Electrical Characteristics”
for values.
© 2009 Microchip Technology Inc.
1.1.2
MULTIPLE OSCILLATOR OPTIONS
AND FEATURES
All of the devices in the PIC18F45J10 family offer three
different oscillator options. These include:
• Two Crystal modes, using crystals or ceramic
resonators
• Two External Clock modes
• INTRC source (approximately 31 kHz)
Besides its availability as a clock source, the internal
oscillator block provides a stable reference source that
gives the family additional features for robust
operation:
• Fail-Safe Clock Monitor: This option constantly
monitors the main clock source against a reference signal provided by the internal oscillator. If a
clock failure occurs, the controller is switched to
the internal oscillator block, allowing for continued
low-speed operation or a safe application
shutdown.
• Two-Speed Start-up: This option allows the
internal oscillator to serve as the clock source
from Power-on Reset, or wake-up from Sleep
mode, until the primary clock source is available.
DS39682E-page 7
PIC18F45J10 FAMILY
1.2
Other Special Features
• Communications: The PIC18F45J10 family
incorporates a range of serial communication
peripherals, including 1 independent Enhanced
USART and 2 Master SSP modules capable of
both SPI and I2C (Master and Slave) modes of
operation. Also, one of the general purpose I/O
ports can be reconfigured as an 8-bit Parallel
Slave Port for direct processor-to-processor
communications.
• Self-Programmability: These devices can write
to their own program memory spaces under
internal software control. By using a bootloader
routine, it becomes possible to create an
application that can update itself in the field.
• Extended Instruction Set: The PIC18F45J10
family introduces an optional extension to the
PIC18 instruction set, which adds 8 new instructions and an Indexed Addressing mode. This
extension, enabled as a device configuration
option, has been specifically designed to optimize
re-entrant application code originally developed in
high-level languages, such as C.
• Enhanced CCP module: In PWM mode, this
module provides 1, 2 or 4 modulated outputs for
controlling half-bridge and full-bridge drivers.
Other features include Auto-Shutdown, for
disabling PWM outputs on interrupt or other select
conditions and Auto-Restart, to reactivate outputs
once the condition has cleared.
• Enhanced Addressable USART: This serial
communication module is capable of standard
RS-232 operation and provides support for the
LIN/J2602 protocol. Other enhancements include
automatic baud rate detection and a 16-bit Baud
Rate Generator for improved resolution.
• 10-bit A/D Converter: This module incorporates
programmable acquisition time, allowing for a
channel to be selected and a conversion to be
initiated without waiting for a sampling period and
thus, reduce code overhead.
• Extended Watchdog Timer (WDT): This
enhanced version incorporates a 16-bit prescaler,
allowing an extended time-out range that is stable
across operating voltage and temperature. See
Section 24.0 “Electrical Characteristics” for
time-out periods.
DS39682E-page 8
1.3
Details on Individual Family
Members
Devices in the PIC18F45J10 family are available in
28-pin and 40/44-pin packages. Block diagrams for the
two groups are shown in Figure 1-1 and Figure 1-2.
The devices are differentiated from each other in five
ways:
1.
2.
3.
4.
5.
6.
7.
Flash program memory (16 Kbytes for
PIC18F24J10/44J10 devices and 32 Kbytes for
PIC18F25J10/45J10).
A/D channels (10 for 28-pin devices, 13 for
40/44-pin devices).
I/O ports (3 bidirectional ports on 28-pin devices,
5 bidirectional ports on 40/44-pin devices).
CCP and Enhanced CCP implementation
(28-pin devices have 2 standard CCP modules, 40/44-pin devices have one standard CCP
module and one ECCP module).
Parallel Slave Port (present only on 40/44-pin
devices).
One MSSP module for PIC18F24J10/25J10
devices
and
2
MSSP
modules
for
PIC18F44J10/45J10 devices
Parts designated with an “F” part number (i.e.,
PIC18F25J10) have a minimum VDD of 2.7 volts,
whereas parts designated with an “LF” part
number (i.e., PIC18LF25J10) can operate
between 2.0-3.6 volts on VDD; however,
VDDCORE should never exceed VDD.
All of the other features for devices in this family are
identical. These are summarized in Table 1-1.
The pinouts for all devices are listed in Table 1-2 and
Table 1-3.
The PIC18F45J10 family of devices provides an on-chip
voltage regulator to supply the correct voltage levels to
the core. Parts designated with an “F” part number (such
as PIC18F25J10) have the voltage regulator enabled.
These parts can run from 2.7-3.6 volts on VDD but should
have the VDDCORE pin connected to VSS through a lowESR capacitor. Parts designated with an “LF” part
number (such as PIC18LF24J10) do not enable the
voltage regulator. An external supply of 2.0-2.7 Volts has
to be supplied to the VDDCORE pin while 2.0-3.6 Volts
can be supplied to VDD (VDDCORE should never exceed
VDD). See Section 21.3 “On-Chip Voltage Regulator”
for more details about the internal voltage regulator.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-1:
DEVICE FEATURES
Features
Operating Frequency
PIC18F24J10
PIC18F25J10
PIC18F44J10
PIC18F45J10
DC – 40 MHz
DC – 40 MHz
DC – 40 MHz
DC – 40 MHz
Program Memory (Bytes)
16384
32768
16384
32768
Program Memory
(Instructions)
8192
16384
8192
16384
Data Memory (Bytes)
1024
1024
1024
1024
Interrupt Sources
I/O Ports
19
19
20
20
Ports A, B, C
Ports A, B, C
Ports A, B, C, D, E
Ports A, B, C, D, E
Timers
3
3
3
3
Capture/Compare/PWM Modules
2
2
1
1
Enhanced
Capture/Compare/PWM Modules
0
0
1
1
MSSP,
Enhanced USART
MSSP,
Enhanced USART
MSSP,
Enhanced USART
MSSP,
Enhanced USART
Serial Communications
Parallel Communications (PSP)
No
No
Yes
Yes
10-Bit Analog-to-Digital Module
10 Input Channels
10 Input Channels
13 Input Channels
13 Input Channels
Resets (and Delays)
POR, BOR(1),
RESET Instruction,
Stack Full, Stack
Underflow (PWRT,
OST),
MCLR, WDT
POR, BOR(1),
RESET Instruction,
Stack Full, Stack
Underflow (PWRT,
OST),
MCLR, WDT
POR, BOR(1),
RESET Instruction,
Stack Full, Stack
Underflow (PWRT,
OST),
MCLR, WDT
POR, BOR(1),
RESET Instruction,
Stack Full, Stack
Underflow (PWRT,
OST),
MCLR, WDT
Yes
Yes
Yes
Yes
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
75 Instructions;
83 with Extended
Instruction Set enabled
28-pin SPDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
28-pin SPDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
40-pin PDIP
44-pin QFN
44-pin TQFP
40-pin PDIP
44-pin QFN
44-pin TQFP
Programmable Brown-out Reset
Instruction Set
Packages
Note 1:
BOR is not available in PIC18LF2XJ10/4XJ10 devices.
© 2009 Microchip Technology Inc.
DS39682E-page 9
PIC18F45J10 FAMILY
FIGURE 1-1:
PIC18F24J10/25J10 (28-PIN) BLOCK DIAGRAM
Data Bus<8>
Table Pointer<21>
Data Latch
8
8
inc/dec logic
PCLATU PCLATH
21
20
31 Level Stack
Address Latch
STKPTR
RA5/AN4/SS1/C2OUT
12
Data Address<12>
4
BSR
Data Latch
8
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
Address Latch
PCU PCH PCL
Program Counter
Program Memory
(16/32 Kbytes)
PORTA
Data Memory
(1 Kbyte)
12
FSR0
FSR1
FSR2
4
Access
Bank
12
PORTB
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2(1)
RB4/KBI0/AN11
RB5/KBI1/T0CKI/C1OUT
RB6/KBI2/PGC
RB7/KBI3/PGD
inc/dec
logic
Table Latch
Address
Decode
ROM Latch
Instruction Bus <16>
IR
Instruction
Decode and
Control
8
State Machine
Control Signals
PRODH PRODL
3
Internal
Oscillator
Block
Power-up
Timer
INTRC
Oscillator
T1OSI
Oscillator
Start-up Timer
Power-on
Reset
T1OSO
Watchdog
Timer
OSC1
OSC2
Single-Supply
Programming
In-Circuit
Debugger
MCLR
VDD, VSS
Note
Brown-out(2)
Reset
Fail-Safe
Clock Monitor
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1
RC3/SCK1/SCL1
RC4/SDI1/SDA1
RC5/SDO1
RC6/TX/CK
RC7/RX/DT
8
W
BITOP
8
VDDCORE
PORTC
8 x 8 Multiply
8
8
8
8
ALU<8>
8
Precision
Band Gap
Reference
BOR(2)
Timer0
Timer1
Timer2
ADC
10-Bit
Comparator
CCP1
CCP2
MSSP
EUSART
1:
CCP2 is multiplexed with RC1 when Configuration bit, CCP2MX, is set, or RB3 when CCP2MX is not set.
2:
Brown-out Reset is not available in PIC18LF2XJ10/4XJ10 devices.
DS39682E-page 10
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 1-2:
PIC18F44J10/45J10 (40/44-PIN) BLOCK DIAGRAM
Data Bus<8>
Table Pointer<21>
Data Memory
(3.9 Kbytes)
PCLATU PCLATH
21
20
12
Data Address<12>
31 Level Stack
4
BSR
Address Latch
STKPTR
Data Latch
8
RA5/AN4/SS1/C2OUT
Address Latch
PCU PCH PCL
Program Counter
Program Memory
(16/32 Kbytes)
RA0/AN0
RA1/AN1
RA2/AN2/VREF-/CVREF
RA3/AN3/VREF+
Data Latch
8
8
inc/dec logic
PORTA
12
FSR0
FSR1
FSR2
PORTB
RB0/INT0/FLT0/AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2(1)
RB4/KBI0/AN11
RB5/KBI1/T0CKI/C1OUT
RB6/KBI2/PGC
RB7/KBI3/PGD
4
Access
Bank
12
inc/dec
logic
Table Latch
PORTC
Address
Decode
ROM Latch
Instruction Bus <16>
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2(1)
RC2/CCP1/P1A
RC3/SCK1/SCL1
RC4/SDI1/SDA1
RC5/SDO1
RC6/TX/CK
RC7/RX/DT
IR
Instruction
Decode and
Control
8
State Machine
Control Signals
PRODH PRODL
3
Internal
Oscillator
Block
Power-up
Timer
INTRC
Oscillator
T1OSI
Oscillator
Start-up Timer
Power-on
Reset
T1OSO
Watchdog
Timer
OSC1
OSC2
MCLR
VDD, VSS
Note
Single-Supply
Programming
In-Circuit
Debugger
(2)
Brown-out
Reset
Fail-Safe
Clock Monitor
RD0/PSP0/SCK2/SCL2
RD1/PSP1/SDI2/SDA2
RD2/PSP2/SDO2
RD3/PSP3/SS2
RD4/PSP4
RD5/PSP5/P1B
RD6/PSP6/P1C
RD7/PSP7/P1D
8
W
BITOP
8
VDDCORE
PORTD
8 x 8 Multiply
8
8
8
8
ALU<8>
8
PORTE
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
Precision
Band Gap
Reference
BOR(2)
Timer0
Timer1
Timer2
ADC
10-Bit
Comparator
ECCP1
CCP2
MSSP
EUSART
1:
CCP2 is multiplexed with RC1 when Configuration bit, CCP2MX, is set, or RB3 when CCP2MX is not set.
2:
Brown-out Reset is not available in PIC18LF2XJ10/4XJ10 devices.
© 2009 Microchip Technology Inc.
DS39682E-page 11
PIC18F45J10 FAMILY
TABLE 1-2:
PIC18F24J10/25J10 PINOUT I/O DESCRIPTIONS
Pin Number
Pin Name
Pin Buffer
SPDIP,
SOIC, QFN Type Type
SSOP
MCLR
MCLR
1
OSC1/CLKI
OSC1
9
26
I
ST
I
I
—
CMOS
O
—
O
—
6
CLKI
OSC2/CLKO
OSC2
CLKO
10
7
Description
Master Clear (input) or programming voltage (input).
Master Clear (Reset) input. This pin is an active-low
Reset to the device.
Oscillator crystal or external clock input.
Oscillator crystal input or external clock source input.
External clock source input. Always associated with pin
function OSC1. See related OSC2/CLKO pins.
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In EC mode, OSC2 pin outputs CLKO which has 1/4 the
frequency of OSC1 and denotes the instruction cycle rate.
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39682E-page 12
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-2:
PIC18F24J10/25J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
SPDIP,
SOIC, QFN Type Type
SSOP
Description
PORTA is a bidirectional I/O port.
RA0/AN0
RA0
AN0
2
RA1/AN1
RA1
AN1
3
RA2/AN2/VREF-/CVREF
RA2
AN2
VREFCVREF
4
RA3/AN3/VREF+
RA3
AN3
VREF+
5
RA5/AN4/SS1/C2OUT
RA5
AN4
SS1
C2OUT
7
27
I/O
TTL
I Analog
Digital I/O.
Analog Input 0.
I/O
TTL
I Analog
Digital I/O.
Analog Input 1.
I/O
TTL
I Analog
I Analog
O Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
Comparator reference voltage output.
I/O
TTL
I Analog
I Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
I/O
TTL
I Analog
I
TTL
O
—
Digital I/O.
Analog Input 4.
SPI slave select input.
Comparator 2 output.
28
1
2
4
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 13
PIC18F45J10 FAMILY
TABLE 1-2:
PIC18F24J10/25J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
SPDIP,
SOIC, QFN Type Type
SSOP
Description
PORTB is a bidirectional I/O port. PORTB can be software
programmed for internal weak pull-ups on all inputs.
RB0/INT0/FLT0/AN12
RB0
INT0
FLT0
AN12
21
RB1/INT1/AN10
RB1
INT1
AN10
22
RB2/INT2/AN8
RB2
INT2
AN8
23
RB3/AN9/CCP2
RB3
AN9
CCP2(1)
24
RB4/KBI0/AN11
RB4
KBI0
AN11
25
RB5/KBI1/T0CKI/
C1OUT
RB5
KBI1
T0CKI
C1OUT
26
RB6/KBI2/PGC
RB6
KBI2
PGC
27
RB7/KBI3/PGD
RB7
KBI3
PGD
28
18
I/O
TTL
I
ST
I
ST
I Analog
Digital I/O.
External Interrupt 0.
PWM Fault input for CCP1.
Analog input 12.
I/O
TTL
I
ST
I Analog
Digital I/O.
External Interrupt 1.
Analog input 10.
I/O
TTL
I
ST
I Analog
Digital I/O.
External Interrupt 2.
Analog input 8.
I/O
TTL
I Analog
I/O
ST
Digital I/O.
Analog Input 9.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
TTL
I
TTL
I Analog
Digital I/O.
Interrupt-on-change pin.
Analog Input 11.
I/O
I
I
O
TTL
TTL
ST
—
Digital I/O.
Interrupt-on-change pin.
Timer0 external clock input.
Comparator 1 output.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP™ programming clock pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming data pin.
19
20
21
22
23
24
25
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39682E-page 14
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-2:
PIC18F24J10/25J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
Pin Buffer
SPDIP,
SOIC, QFN Type Type
SSOP
Description
PORTC is a bidirectional I/O port.
RC0/T1OSO/T1CKI
RC0
T1OSO
T1CKI
11
RC1/T1OSI/CCP2
RC1
T1OSI
CCP2(2)
12
RC2/CCP1
RC2
CCP1
13
RC3/SCK1/SCL1
RC3
SCK1
SCL1
14
RC4/SDI1/SDA1
RC4
SDI1
SDA1
15
RC5/SDO1
RC5
SDO1
16
RC6/TX/CK
RC6
TX
CK
17
RC7/RX/DT
RC7
RX
DT
18
8
I/O
O
I
ST
—
ST
Digital I/O.
Timer1 oscillator output.
Timer1 external clock input.
9
I/O
ST
I Analog
I/O
ST
Digital I/O.
Timer1 oscillator input.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I/O
ST
ST
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
I/O
I/O
I/O
ST
ST
ST
Digital I/O.
Synchronous serial clock input/output for SPI mode.
Synchronous serial clock input/output for I2C™ mode.
I/O
I
I/O
ST
ST
ST
Digital I/O.
SPI data in.
I2C data I/O.
I/O
O
ST
—
Digital I/O.
SPI data out.
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX/DT).
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX/CK).
10
11
12
13
14
15
VSS
8, 19
5, 16
P
—
Ground reference for logic and I/O pins.
VDD
20
17
P
—
Positive supply for logic and I/O pins.
VDDCORE/VCAP
VDDCORE
VCAP
6
3
P
P
—
—
Positive supply for logic and I/O pins.
Ground reference for logic and I/O pins.
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 15
PIC18F45J10 FAMILY
TABLE 1-3:
Pin Name
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS
Pin Number
PDIP
MCLR
MCLR
1
OSC1/CLKI
OSC1
CLKI
13
OSC2/CLKO
OSC2
14
CLKO
Pin Buffer
QFN TQFP Type Type
18
32
33
18
Description
I
ST
Master Clear (input) or programming voltage (input).
Master Clear (Reset) input. This pin is an active-low
Reset to the device.
I
I
—
CMOS
Oscillator crystal or external clock input.
Oscillator crystal input or external clock source input.
External clock source input. Always associated with
pin function OSC1. See related OSC2/CLKO pins.
O
—
O
—
30
31
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal
or resonator in Crystal Oscillator mode.
In RC mode, OSC2 pin outputs CLKO which
has 1/4 the frequency of OSC1 and denotes
the instruction cycle rate.
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39682E-page 16
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-3:
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTA is a bidirectional I/O port.
RA0/AN0
RA0
AN0
2
RA1/AN1
RA1
AN1
3
RA2/AN2/VREF-/CVREF
RA2
AN2
VREFCVREF
4
RA3/AN3/VREF+
RA3
AN3
VREF+
5
RA5/AN4/SS1/C2OUT
RA5
AN4
SS1
C2OUT
7
19
20
21
22
24
19
I/O
I
TTL
Analog
Digital I/O.
Analog Input 0.
I/O
I
TTL
Analog
Digital I/O.
Analog Input 1.
I/O
I
I
O
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
Comparator reference voltage output.
I/O
I
I
TTL
Analog
Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
I/O
I
I
O
TTL
Analog
TTL
—
Digital I/O.
Analog Input 4.
SPI slave select input.
Comparator 2 output.
20
21
22
24
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 17
PIC18F45J10 FAMILY
TABLE 1-3:
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTB is a bidirectional I/O port. PORTB can be
software programmed for internal weak pull-ups on
all inputs.
RB0/INT0/FLT0/AN12
RB0
INT0
FLT0
AN12
33
RB1/INT1/AN10
RB1
INT1
AN10
34
RB2/INT2/AN8
RB2
INT2
AN8
35
RB3/AN9/CCP2
RB3
AN9
CCP2(1)
36
RB4/KBI0/AN11
RB4
KBI0
AN11
37
RB5/KBI1/C1OUT
RB5
KBI1
C1OUT
38
RB6/KBI2/PGC
RB6
KBI2
PGC
39
RB7/KBI3/PGD
RB7
KBI3
PGD
40
9
10
11
12
14
15
16
17
8
I/O
I
I
I
TTL
ST
ST
Analog
Digital I/O.
External Interrupt 0.
PWM Fault input for Enhanced CCP1.
Analog input 12.
I/O
I
I
TTL
ST
Analog
Digital I/O.
External Interrupt 1.
Analog input 10.
I/O
I
I
TTL
ST
Analog
Digital I/O.
External Interrupt 2.
Analog input 8.
I/O
I
I/O
TTL
Analog
ST
Digital I/O.
Analog Input 9.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I
I
TTL
TTL
Analog
Digital I/O.
Interrupt-on-change pin.
Analog Input 11.
I/O
I
O
TTL
TTL
—
Digital I/O.
Interrupt-on-change pin.
Comparator 1 output.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP™ programming
clock pin.
I/O
I
I/O
TTL
TTL
ST
Digital I/O.
Interrupt-on-change pin.
In-Circuit Debugger and ICSP programming
data pin.
9
10
11
14
15
16
17
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39682E-page 18
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-3:
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTC is a bidirectional I/O port.
RC0/T1OSO/T1CKI
RC0
T1OSO
T1CKI
15
RC1/T1OSI/CCP2
RC1
T1OSI
CCP2(2)
16
RC2/CCP1/P1A
RC2
CCP1
P1A
17
RC3/SCK1/SCL1
RC3
SCK1
18
34
35
36
37
32
23
RC5/SDO1
RC5
SDO1
24
RC6/TX/CK
RC6
TX
CK
25
RC7/RX/DT
RC7
RX
DT
26
42
43
44
1
ST
—
ST
Digital I/O.
Timer1 oscillator output.
Timer1 external clock input.
I/O
I
I/O
ST
CMOS
ST
Digital I/O.
Timer1 oscillator input.
Capture 2 input/Compare 2 output/PWM2 output.
I/O
I/O
O
ST
ST
—
Digital I/O.
Capture 1 input/Compare 1 output/PWM1 output.
Enhanced CCP1 output.
I/O
I/O
ST
ST
I/O
ST
Digital I/O.
Synchronous serial clock input/output for
SPI mode.
Synchronous serial clock input/output for
I2C™ mode.
I/O
I
I/O
ST
ST
ST
Digital I/O.
SPI data in.
I2C data I/O.
I/O
O
ST
—
Digital I/O.
SPI data out.
I/O
O
I/O
ST
—
ST
Digital I/O.
EUSART asynchronous transmit.
EUSART synchronous clock (see related RX/DT).
I/O
I
I/O
ST
ST
ST
Digital I/O.
EUSART asynchronous receive.
EUSART synchronous data (see related TX/CK).
35
36
37
SCL1
RC4/SDI1/SDA1
RC4
SDI1
SDA1
I/O
O
I
42
43
44
1
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 19
PIC18F45J10 FAMILY
TABLE 1-3:
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Name
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTD is a bidirectional I/O port or a Parallel Slave
Port (PSP) for interfacing to a microprocessor port.
These pins have TTL input buffers when PSP module
is enabled.
RD0/PSP0/SCK2/
SCL2
RD0
PSP0
SCK2
19
38
38
SCL2
RD1/PSP1/SDI2/SDA2
RD1
PSP1
SDI2
SDA2
20
RD2/PSP2/SDO2
RD2
PSP2
SDO2
21
RD3/PSP3/SS2
RD3
PSP3
SS2
22
RD4/PSP4
RD4
PSP4
27
RD5/PSP5/P1B
RD5
PSP5
P1B
28
RD6/PSP6/P1C
RD6
PSP6
P1C
29
RD7/PSP7/P1D
RD7
PSP7
P1D
30
39
40
41
2
3
4
5
I/O
I/O
I/O
ST
TTL
ST
I/O
ST
I/O
I/O
I
I/O
ST
TTL
ST
ST
Digital I/O.
Parallel Slave Port data.
SPI data in.
I2C data I/O.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
SPI data out.
I/O
I/O
I
ST
TTL
TTL
Digital I/O.
Parallel Slave Port data.
SPI slave select input.
I/O
I/O
ST
TTL
Digital I/O.
Parallel Slave Port data.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
I/O
I/O
O
ST
TTL
—
Digital I/O.
Parallel Slave Port data.
Enhanced CCP1 output.
Digital I/O.
Parallel Slave Port data.
Synchronous serial clock input/output for
SPI mode.
Synchronous serial clock input/output for
I2C™ mode.
39
40
41
2
3
4
5
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
DS39682E-page 20
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 1-3:
Pin Name
PIC18F44J10/45J10 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
Pin Buffer
QFN TQFP Type Type
Description
PORTE is a bidirectional I/O port.
RE0/RD/AN5
RE0
RD
8
25
25
I/O
I
ST
TTL
I
Analog
I/O
I
ST
TTL
I
Analog
I/O
I
ST
TTL
I
Analog
6, 29
P
—
Ground reference for logic and I/O pins.
7, 8, 7, 28
28, 29
P
—
Positive supply for logic and I/O pins.
P
P
—
—
Positive supply for logic and I/O pins.
Ground reference for logic and I/O pins.
—
—
No connect.
AN5
RE1/WR/AN6
RE1
WR
9
26
26
AN6
RE2/CS/AN7
RE2
CS
10
27
12, 31 6, 30,
31
VDD
11, 32
VDDCORE/VCAP
VDDCORE
VCAP
6
NC
—
23
13
Digital I/O.
Write control for Parallel Slave Port
(see CS and RD pins).
Analog input 6.
27
AN7
VSS
Digital I/O.
Read control for Parallel Slave Port
(see also WR and CS pins).
Analog input 5.
Digital I/O.
Chip Select control for Parallel Slave Port
(see related RD and WR pins).
Analog input 7.
23
12, 13,
33, 34
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
Note 1: Default assignment for CCP2 when Configuration bit, CCP2MX, is set.
2: Alternate assignment for CCP2 when Configuration bit, CCP2MX, is cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 21
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 22
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
2.0
GUIDELINES FOR GETTING
STARTED WITH PIC18FJ
MICROCONTROLLERS
FIGURE 2-1:
RECOMMENDED
MINIMUM CONNECTIONS
C2(2)
• All VDD and VSS pins
(see Section 2.2 “Power Supply Pins”)
• All AVDD and AVSS pins, regardless of whether or
not the analog device features are used
(see Section 2.2 “Power Supply Pins”)
• MCLR pin
(see Section 2.3 “Master Clear (MCLR) Pin”)
• ENVREG (if implemented) and VCAP/VDDCORE pins
(see Section 2.4 “Voltage Regulator Pins
(VCAP/VDDCORE)”)
VCAP/VDDCORE
C1
VSS
VDD
VDD
VSS
C3(2)
C6(2)
C5(2)
C4(2)
Key (all values are recommendations):
• PGC/PGD pins used for In-Circuit Serial
Programming™ (ICSP™) and debugging purposes
(see Section 2.5 “ICSP Pins”)
• OSCI and OSCO pins when an external oscillator
source is used
(see Section 2.6 “External Oscillator Pins”)
R1: 10 kΩ
Note:
C7
PIC18FXXJXX
C1 through C6: 0.1 μF, 20V ceramic
• VREF+/VREF- pins used when external voltage
reference for analog modules is implemented
(1) (1)
ENVREG
MCLR
These pins must also be connected if they are being
used in the end application:
Additionally, the following pins may be required:
VSS
VDD
R2
VSS
The following pins must always be connected:
R1
VDD
Getting started with the PIC18F45J10 family family of
8-bit microcontrollers requires attention to a minimal
set of device pin connections before proceeding with
development.
VDD
AVSS
Basic Connection Requirements
AVDD
2.1
C7: 10 μF, 6.3V or greater, tantalum or ceramic
R2: 100Ω to 470Ω
Note 1:
2:
See Section 2.4 “Voltage Regulator Pins
(VCAP/VDDCORE)” for explanation of
ENVREG pin connections.
The example shown is for a PIC18FJ device
with five VDD/VSS and AVDD/AVSS pairs.
Other devices may have more or less pairs;
adjust the number of decoupling capacitors
appropriately.
The AVDD and AVSS pins must always be
connected, regardless of whether any of
the analog modules are being used.
The minimum mandatory connections are shown in
Figure 2-1.
© 2009 Microchip Technology Inc.
DS39682E-page 23
PIC18F45J10 FAMILY
2.2
2.2.1
Power Supply Pins
DECOUPLING CAPACITORS
The use of decoupling capacitors on every pair of
power supply pins, such as VDD, VSS, AVDD and
AVSS, is required.
Consider the following criteria when using decoupling
capacitors:
• Value and type of capacitor: A 0.1 μF (100 nF),
10-20V capacitor is recommended. The capacitor
should be a low-ESR device with a resonance
frequency in the range of 200 MHz and higher.
Ceramic capacitors are recommended.
• Placement on the printed circuit board: The
decoupling capacitors should be placed as close
to the pins as possible. It is recommended to
place the capacitors on the same side of the
board as the device. If space is constricted, the
capacitor can be placed on another layer on the
PCB using a via; however, ensure that the trace
length from the pin to the capacitor is no greater
than 0.25 inch (6 mm).
• Handling high-frequency noise: If the board is
experiencing high-frequency noise (upward of
tens of MHz), add a second ceramic type capacitor in parallel to the above described decoupling
capacitor. The value of the second capacitor can
be in the range of 0.01 μF to 0.001 μF. Place this
second capacitor next to each primary decoupling
capacitor. In high-speed circuit designs, consider
implementing a decade pair of capacitances as
close to the power and ground pins as possible
(e.g., 0.1 μF in parallel with 0.001 μF).
• Maximizing performance: On the board layout
from the power supply circuit, run the power and
return traces to the decoupling capacitors first,
and then to the device pins. This ensures that the
decoupling capacitors are first in the power chain.
Equally important is to keep the trace length
between the capacitor and the power pins to
a minimum, thereby reducing PCB trace
inductance.
2.2.2
TANK CAPACITORS
On boards with power traces running longer than six
inches in length, it is suggested to use a tank capacitor
for integrated circuits including microcontrollers to
supply a local power source. The value of the tank
capacitor should be determined based on the trace
resistance that connects the power supply source to
the device and the maximum current drawn by the
device in the application. In other words, select the tank
capacitor so that it meets the acceptable voltage sag at
the device. Typical values range from 4.7 μF to 47 μF.
DS39682E-page 24
2.3
Master Clear (MCLR) Pin
The MCLR pin provides two specific device
functions: device Reset, and device programming
and debugging. If programming and debugging are
not required in the end application, a direct
connection to VDD may be all that is required. The
addition of other components, to help increase the
application’s resistance to spurious Resets from
voltage sags, may be beneficial. A typical
configuration is shown in Figure 2-1. Other circuit
designs may be implemented depending on the
application’s requirements.
During programming and debugging, the resistance
and capacitance that can be added to the pin must
be considered. Device programmers and debuggers
drive the MCLR pin. Consequently, specific voltage
levels (VIH and VIL) and fast signal transitions must
not be adversely affected. Therefore, specific values
of R1 and C1 will need to be adjusted based on the
application and PCB requirements. For example, it is
recommended that the capacitor, C1, be isolated
from the MCLR pin during programming and
debugging operations by using a jumper (Figure 2-2).
The jumper is replaced for normal run-time
operations.
Any components associated with the MCLR pin
should be placed within 0.25 inch (6 mm) of the pin.
FIGURE 2-2:
EXAMPLE OF MCLR PIN
CONNECTIONS
VDD
R1
R2
JP
MCLR
PIC18FXXJXX
C1
Note 1:
R1 ≤ 10 kΩ is recommended. A suggested
starting value is 10 kΩ. Ensure that the
MCLR pin VIH and VIL specifications are met.
2:
R2 ≤ 470Ω will limit any current flowing into
MCLR from the external capacitor, C, in the
event of MCLR pin breakdown, due to
Electrostatic Discharge (ESD) or Electrical
Overstress (EOS). Ensure that the MCLR pin
VIH and VIL specifications are met.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
2.4
Voltage Regulator Pins
(VCAP/VDDCORE)
2.5
When the regulator is enabled (F devices), a low-ESR
(<5Ω) capacitor is required on the VCAP/VDDCORE pin to
stabilize the voltage regulator output voltage. The
VCAP/VDDCORE pin must not be connected to VDD and
must use a capacitor (10 μF typical) connected to
ground. The type can be ceramic or tantalum. A suitable
example is the Murata GRM21BF50J106ZE01 (10 μF,
6.3V) or equivalent. Designers may use Figure 2-3 to
evaluate ESR equivalence of candidate devices.
It is recommended that the trace length not exceed
0.25 inch (6 mm). Refer to Section 24.0 “Electrical
Characteristics” for additional information.
When the regulator is disabled (LF devices), the
VCAP/VDDCORE pin must be tied to a voltage supply at
the VDDCORE level. Refer to Section 24.0 “Electrical
Characteristics” for information on VDD and
VDDCORE.
FIGURE 2-3:
FREQUENCY vs. ESR
PERFORMANCE FOR
SUGGESTED VCAP
10
ESR (Ω)
The PGC and PGD pins are used for In-Circuit Serial
Programming (ICSP) and debugging purposes. It is
recommended to keep the trace length between the
ICSP connector and the ICSP pins on the device as
short as possible. If the ICSP connector is expected to
experience an ESD event, a series resistor is recommended, with the value in the range of a few tens of
ohms, not to exceed 100Ω.
Pull-up resistors, series diodes and capacitors on the
PGC and PGD pins are not recommended as they will
interfere with the programmer/debugger communications to the device. If such discrete components
are an application requirement, they should be removed
from the circuit during programming and debugging.
Alternatively, refer to the AC/DC characteristics and
timing requirements information in the respective device
Flash programming specification for information on
capacitive loading limits and pin input voltage high (VIH)
and input low (VIL) requirements.
For device emulation, ensure that the “Communication
Channel Select” (i.e., PGC/PGD pins) programmed
into the device matches the physical connections for
the ICSP to the MPLAB® ICD 2, MPLAB ICD 3 or
REAL ICE™ emulator.
For more information on the ICD 2, ICD 3 and REAL ICE
emulator connection requirements, refer to the following
documents that are available on the Microchip web site.
1
0.1
0.01
0.001
ICSP Pins
0.01
Note:
0.1
1
10
100
Frequency (MHz)
1000 10,000
Data for Murata GRM21BF50J106ZE01 shown.
Measurements at 25°C, 0V DC bias.
© 2009 Microchip Technology Inc.
• “MPLAB® ICD 2 In-Circuit Debugger User’s
Guide” (DS51331)
• “Using MPLAB® ICD 2” (poster) (DS51265)
• “MPLAB® ICD 2 Design Advisory” (DS51566)
• “Using MPLAB® ICD 3” (poster) (DS51765)
• “MPLAB® ICD 3 Design Advisory” (DS51764)
• “MPLAB® REAL ICE™ In-Circuit Emulator User’s
Guide” (DS51616)
• “Using MPLAB® REAL ICE™ In-Circuit Emulator”
(poster) (DS51749)
DS39682E-page 25
PIC18F45J10 FAMILY
2.6
External Oscillator Pins
FIGURE 2-4:
Many microcontrollers have options for at least two
oscillators: a high-frequency primary oscillator and a
low-frequency
secondary
oscillator
(refer to
Section 3.0 “Oscillator Configurations” for details).
Main Oscillator
13
The oscillator circuit should be placed on the same
side of the board as the device. Place the oscillator
circuit close to the respective oscillator pins with no
more than 0.5 inch (12 mm) between the circuit
components and the pins. The load capacitors should
be placed next to the oscillator itself, on the same side
of the board.
Use a grounded copper pour around the oscillator
circuit to isolate it from surrounding circuits. The
grounded copper pour should be routed directly to the
MCU ground. Do not run any signal traces or power
traces inside the ground pour. Also, if using a
two-sided board, avoid any traces on the other side of
the board where the crystal is placed. A suggested
layout is shown in Figure 2-4.
For additional information and design guidance on
oscillator circuits, please refer to these Microchip
Application Notes, available at the corporate web site
(www.microchip.com):
SUGGESTED PLACEMENT
OF THE OSCILLATOR
CIRCUIT
Guard Ring
14
15
Guard Trace
16
17
Secondary
Oscillator
18
19
20
2.7
Unused I/Os
Unused I/O pins should be configured as outputs and
driven to a logic low state. Alternatively, connect a 1 kΩ
to 10 kΩ resistor to VSS on unused pins and drive the
output to logic low.
• AN826, “Crystal Oscillator Basics and Crystal
Selection for rfPIC™ and PICmicro® Devices”
• AN849, “Basic PICmicro® Oscillator Design”
• AN943, “Practical PICmicro® Oscillator Analysis
and Design”
• AN949, “Making Your Oscillator Work”
DS39682E-page 26
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
3.0
OSCILLATOR
CONFIGURATIONS
3.1
Oscillator Types
The PIC18F45J10 family of devices can be operated in
five different oscillator modes:
1.
2.
HS
High-Speed Crystal/Resonator
HSPLL High-Speed Crystal/Resonator
with Software PLL Control
EC
External Clock with FOSC/4 Output
ECPLL External Clock with Software PLL
Control
INTRC Internal 31 kHz Oscillator
3.
4.
5.
FIGURE 3-1:
C1(1)
Crystal Oscillator/Ceramic
Resonators (HS Modes)
In HS or HSPLL Oscillator modes, a crystal or ceramic
resonator is connected to the OSC1 and OSC2 pins to
establish oscillation. Figure 3-1 shows the pin
connections.
The oscillator design requires the use of a parallel cut
crystal.
Note:
Use of a series cut crystal may give a frequency out of the crystal manufacturer’s
specifications.
OSC1
XTAL
To
Internal
Logic
RF(3)
Sleep
OSC2
PIC18F45J10
RS(2)
C2(1)
Note 1:
See Table 3-1 and Table 3-2 for initial values of
C1 and C2.
2:
A series resistor (RS) may be required for AT
strip cut crystals.
3:
RF varies with the oscillator mode chosen.
Four of these are selected by the user by programming
the FOSC<2:0> Configuration bits. The fifth mode
(INTRC) may be invoked under software control; it can
also be configured as the default mode on device
Resets.
3.2
CRYSTAL/CERAMIC
RESONATOR OPERATION
(HS OR HSPLL
CONFIGURATION)
TABLE 3-1:
CAPACITOR SELECTION FOR
CERAMIC RESONATORS
Typical Capacitor Values Used:
Mode
Freq.
OSC1
OSC2
HS
8.0 MHz
16.0 MHz
27 pF
22 pF
27 pF
22 pF
Capacitor values are for design guidance only.
These capacitors were tested with the resonators
listed below for basic start-up and operation. These
values are not optimized.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application.
See the notes following Table 3-2 for additional
information.
Resonators Used:
4.0 MHz
8.0 MHz
16.0 MHz
© 2009 Microchip Technology Inc.
DS39682E-page 27
PIC18F45J10 FAMILY
TABLE 3-2:
Osc Type
HS
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR
Crystal
Freq.
Typical Capacitor Values
Tested:
C1
C2
4 MHz
27 pF
27 pF
8 MHz
22 pF
22 pF
20 MHz
15 pF
15 pF
Capacitor values are for design guidance only.
These capacitors were tested with the crystals listed
below for basic start-up and operation. These values
are not optimized.
Different capacitor values may be required to produce
acceptable oscillator operation. The user should test
the performance of the oscillator over the expected
VDD and temperature range for the application.
3.3
External Clock Input (EC Modes)
The EC and ECPLL Oscillator modes require an external clock source to be connected to the OSC1 pin.
There is no oscillator start-up time required after a
Power-on Reset or after an exit from Sleep mode.
In the EC Oscillator mode, the oscillator frequency
divided by 4 is available on the OSC2 pin. This signal
may be used for test purposes or to synchronize other
logic. Figure 3-2 shows the pin connections for the EC
Oscillator mode.
FIGURE 3-2:
EXTERNAL CLOCK
INPUT OPERATION
(EC CONFIGURATION)
OSC1/CLKI
Clock from
Ext. System
See the notes following this table for additional
information.
PIC18F45J10
FOSC/4
OSC2/CLKO
Crystals Used:
4 MHz
8 MHz
20 MHz
Note 1: Higher capacitance increases the stability
of oscillator but also increases the
start-up time.
2: Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate
values
of
external
components.
An external clock source may also be connected to the
OSC1 pin in the HS mode, as shown in Figure 3-3. In
this configuration, the divide-by-4 output on OSC2 is
not available.
FIGURE 3-3:
EXTERNAL CLOCK INPUT
OPERATION (HS OSC
CONFIGURATION)
OSC1
Clock from
Ext. System
PIC18F45J10
Open
OSC2
(HS Mode)
3: Rs may be required to avoid overdriving
crystals with low drive level specification.
4: Always verify oscillator performance over
the VDD and temperature range that is
expected for the application.
DS39682E-page 28
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
3.4
FIGURE 3-4:
PLL Frequency Multiplier
A Phase Locked Loop (PLL) circuit is provided as an
option for users who want to use a lower frequency
oscillator circuit, or to clock the device up to its highest
rated frequency from a crystal oscillator. This may be
useful for customers who are concerned with EMI due
to high-frequency crystals, or users who require higher
clock speeds from an internal oscillator. For these
reasons, the HSPLL and ECPLL modes are available.
PLL BLOCK DIAGRAM
HSPLL or ECPLL (CONFIG2L)
PLL Enable (OSCTUNE)
OSC2
HS or EC
OSC1 Mode
FIN
Phase
Comparator
FOUT
The HSPLL and ECPLL modes provide the ability to
selectively run the device at 4 times the external oscillating source to produce frequencies up to 40 MHz.
The PLL is enabled by setting the PLLEN bit in the
OSCTUNE register (Register 3-1).
Loop
Filter
÷4
MUX
VCO
REGISTER 3-1:
SYSCLK
OSCTUNE: PLL CONTROL REGISTER
U-0
R/W-0
U-0
U-0
U-0
U-0
U-0
U-0
—
PLLEN(1)
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
Unimplemented: Read as ‘0’
bit 6
PLLEN: Frequency Multiplier PLL Enable bit(1)
1 = PLL enabled
0 = PLL disabled
bit 5-0
Unimplemented: Read as ‘0’
Note 1:
x = Bit is unknown
Available only for ECPLL and HSPLL oscillator configurations; otherwise, this bit is unavailable and reads
as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 29
PIC18F45J10 FAMILY
3.5
Internal Oscillator Block
The PIC18F45J10 family of devices includes an internal oscillator source (INTRC) which provides a nominal
31 kHz output. The INTRC is enabled on device
power-up and clocks the device during its configuration
cycle until it enters operating mode. INTRC is also
enabled if it is selected as the device clock source or if
any of the following are enabled:
• Fail-Safe Clock Monitor
• Watchdog Timer
• Two-Speed Start-up
The secondary oscillators are those external sources
not connected to the OSC1 or OSC2 pins. These
sources may continue to operate even after the
controller is placed in a power-managed mode.
PIC18F45J10 family devices offer the Timer1 oscillator
as a secondary oscillator. This oscillator, in all
power-managed modes, is often the time base for
functions such as a Real-Time Clock (RTC).
These features are discussed in greater detail in
Section 21.0 “Special Features of the CPU”.
Most often, a 32.768 kHz watch crystal is connected
between the RC0/T1OSO/T13CKI and RC1/T1OSI
pins. Loading capacitors are also connected from each
pin to ground.
The INTRC can also be optionally configured as the
default clock source on device start-up by setting the
FOSC2 Configuration bit. This is discussed in
Section 3.6.1 “Oscillator Control Register”.
3.6
The primary oscillators include the External Crystal
and Resonator modes and the External Clock modes.
The particular mode is defined by the FOSC<2:0>
Configuration bits. The details of these modes are
covered earlier in this chapter.
The Timer1 oscillator is discussed in greater detail in
Section 12.3 “Timer1 Oscillator”.
Clock Sources and
Oscillator Switching
The PIC18F45J10 family includes a feature that allows
the device clock source to be switched from the main
oscillator to an alternate clock source. PIC18F45J10
family devices offer two alternate clock sources. When
an alternate clock source is enabled, the various
power-managed operating modes are available.
Essentially, there are three clock sources for these
devices:
In addition to being a primary clock source, the internal
oscillator is available as a power-managed mode
clock source. The INTRC source is also used as the
clock source for several special features, such as the
WDT and Fail-Safe Clock Monitor.
The clock sources for the PIC18F45J10 family devices
are shown in Figure 3-5. See Section 21.0 “Special
Features of the CPU” for Configuration register
details.
• Primary oscillators
• Secondary oscillators
• Internal oscillator
FIGURE 3-5:
PIC18F45J10 FAMILY CLOCK DIAGRAM
PIC18F45J10 Family
HS, EC
Sleep
4 x PLL
OSC1
T1OSO
T1OSI
Secondary Oscillator
T1OSCEN
Enable
Oscillator
HSPLL, ECPLL
T1OSC
INTRC
Source
Peripherals
MUX
OSC2
Primary Oscillator
Internal Oscillator
CPU
Clock
Control
FOSC<2:0>
IDLEN
OSCCON<1:0>
Clock Source Option
for Other Modules
WDT, PWRT, FSCM
and Two-Speed Start-up
DS39682E-page 30
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
3.6.1
OSCILLATOR CONTROL REGISTER
The OSCCON register (Register 3-2) controls several
aspects of the device clock’s operation, both in
full-power operation and in power-managed modes.
The System Clock Select bits, SCS<1:0>, select the
clock source. The available clock sources are the
primary clock (defined by the FOSC<2:0> Configuration bits), the secondary clock (Timer1 oscillator) and
the internal oscillator. The clock source changes after
one or more of the bits are written to, following a brief
clock transition interval.
The OSTS (OSCCON<3>) and T1RUN (T1CON<6>)
bits indicate which clock source is currently providing
the device clock. The OSTS bit indicates that the
Oscillator Start-up Timer (OST) has timed out and the
primary clock is providing the device clock in primary
clock modes. The T1RUN bit indicates when the
Timer1 oscillator is providing the device clock in secondary clock modes. In power-managed modes, only
one of these bits will be set at any time. If neither of
these bits is set, the INTRC is providing the clock, or
the internal oscillator has just started and is not yet
stable.
The IDLEN bit determines if the device goes into Sleep
mode or one of the Idle modes when the SLEEP
instruction is executed.
The use of the flag and control bits in the OSCCON
register is discussed in more detail in Section 4.0
“Power-Managed Modes”.
Note 1: The Timer1 oscillator must be enabled to
select the secondary clock source. The
Timer1 oscillator is enabled by setting the
T1OSCEN bit in the Timer1 Control register (T1CON<3>). If the Timer1 oscillator is
not enabled, then any attempt to select a
secondary clock source when executing a
SLEEP instruction will be ignored.
3.6.1.1
System Clock Selection and the
FOSC2 Configuration Bit
The SCS bits are cleared on all forms of Reset. In the
device’s default configuration, this means the primary
oscillator defined by FOSC<1:0> (that is, one of the HC
or EC modes) is used as the primary clock source on
device Resets.
The default clock configuration on Reset can be changed
with the FOSC2 Configuration bit. The effect of this bit is
to set the clock source selected when SCS<1:0> = 00.
When FOSC2 = 1 (default), the oscillator source
defined by FOSC<1:0> is selected whenever
SCS<1:0> = 00. When FOSC2 = 0, the INTRC oscillator
is selected whenever SCS<1:0> = 00. Because the SCS
bits are cleared on Reset, the FOSC2 setting also
changes the default oscillator mode on Reset.
Regardless of the setting of FOSC2, INTRC will always
be enabled on device power-up. It will serve as the
clock source until the device has loaded its configuration values from memory. It is at this point that the
FOSC Configuration bits are read and the oscillator
selection of operational mode is made.
Note that either the primary clock or the internal
oscillator will have two bit setting options, at any given
time, depending on the setting of FOSC2.
3.6.2
OSCILLATOR TRANSITIONS
PIC18F45J10 family devices contain circuitry to
prevent clock “glitches” when switching between clock
sources. A short pause in the device clock occurs during the clock switch. The length of this pause is the sum
of two cycles of the old clock source and three to four
cycles of the new clock source. This formula assumes
that the new clock source is stable.
Clock transitions are discussed in greater detail in
Section 4.1.2 “Entering Power-Managed Modes”.
2: It is recommended that the Timer1
oscillator be operating and stable before
executing the SLEEP instruction or a very
long delay may occur while the Timer1
oscillator starts.
© 2009 Microchip Technology Inc.
DS39682E-page 31
PIC18F45J10 FAMILY
REGISTER 3-2:
OSCCON: OSCILLATOR CONTROL REGISTER
R/W-0
U-0
U-0
U-0
R-q(1)
U-0
R/W-0
R/W-0
IDLEN
—
—
—
OSTS
—
SCS1
SCS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
IDLEN: Idle Enable bit
1 = Device enters an Idle mode on SLEEP instruction
0 = Device enters Sleep mode on SLEEP instruction
bit 6-4
Unimplemented: Read as ‘0’
bit 3
OSTS: Oscillator Start-up Time-out Status bit(1)
1 = Oscillator Start-up Timer (OST) time-out has expired; primary oscillator is running
0 = Oscillator Start-up Timer (OST) time-out is running; primary oscillator is not ready
bit 2
Unimplemented: Read as ‘0’
bit 1-0
SCS<1:0>: System Clock Select bits(4)
11 = Internal oscillator
10 = Primary oscillator
01 = Timer1 oscillator
When FOSC2 = 1:
00 = Primary oscillator
When FOSC2 = 0:
00 = Internal oscillator
Note 1:
3.7
The Reset value is ‘0’ when HS mode and Two-Speed Start-up are both enabled; otherwise, it is ‘1’.
Effects of Power-Managed Modes
on the Various Clock Sources
When PRI_IDLE mode is selected, the designated primary oscillator continues to run without interruption.
For all other power-managed modes, the oscillator
using the OSC1 pin is disabled. The OSC1 pin (and
OSC2 pin if used by the oscillator) will stop oscillating.
In secondary clock modes (SEC_RUN and
SEC_IDLE), the Timer1 oscillator is operating and
providing the device clock. The Timer1 oscillator may
also run in all power-managed modes if required to
clock Timer1 or Timer3.
In RC_RUN and RC_IDLE modes, the internal oscillator provides the device clock source. The 31 kHz
INTRC output can be used directly to provide the clock
and may be enabled to support various special
features, regardless of the power-managed mode (see
Section 21.2 “Watchdog Timer (WDT)” through
Section 21.5 “Fail-Safe Clock Monitor” for more
information on WDT, Fail-Safe Clock Monitor and
Two-Speed Start-up).
DS39682E-page 32
If the Sleep mode is selected, all clock sources are
stopped. Since all the transistor switching currents
have been stopped, Sleep mode achieves the lowest
current consumption of the device (only leakage
currents).
Enabling any on-chip feature that will operate during
Sleep will increase the current consumed during Sleep.
The INTRC is required to support WDT operation. The
Timer1 oscillator may be operating to support a
real-time clock. Other features may be operating that
do not require a device clock source (i.e., MSSP slave,
PSP, INTx pins and others). Peripherals that may add
significant current consumption are listed in
Section 24.2 “DC Characteristics: Power-Down and
Supply Current”.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
3.8
Power-up Delays
Power-up delays are controlled by two timers, so that
no external Reset circuitry is required for most applications. The delays ensure that the device is kept in
Reset until the device power supply is stable under normal circumstances and the primary clock is operating
and stable. For additional information on power-up
delays, see Section 5.6 “Power-up Timer (PWRT)”.
The second timer is the Oscillator Start-up Timer
(OST), intended to keep the chip in Reset until the
crystal oscillator is stable (HS modes). The OST does
this by counting 1024 oscillator cycles before allowing
the oscillator to clock the device.
There is a delay of interval, TCSD (parameter 38,
Table 24-10), following POR, while the controller
becomes ready to execute instructions.
The first timer is the Power-up Timer (PWRT), which
provides a fixed delay on power-up (parameter 33,
Table 24-10). It is always enabled.
TABLE 3-3:
OSC1 AND OSC2 PIN STATES IN SLEEP MODE
Oscillator Mode
OSC1 Pin
OSC2 Pin
EC, ECPLL
Floating, pulled by external clock
At logic low (clock/4 output)
HS, HSPLL
Feedback inverter disabled at quiescent
voltage level
Feedback inverter disabled at quiescent
voltage level
Note:
See Table 5-2 in Section 5.0 “Reset” for time-outs due to Sleep and MCLR Reset.
© 2009 Microchip Technology Inc.
DS39682E-page 33
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 34
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
4.0
4.1.1
POWER-MANAGED MODES
CLOCK SOURCES
The PIC18F45J10 family devices provide the ability to
manage power consumption by simply managing clocking to the CPU and the peripherals. In general, a lower
clock frequency and a reduction in the number of circuits
being clocked constitutes lower consumed power. For
the sake of managing power in an application, there are
three primary modes of operation:
The SCS<1:0> bits allow the selection of one of three
clock sources for power-managed modes. They are:
• Run mode
• Idle mode
• Sleep mode
4.1.2
These modes define which portions of the device are
clocked and at what speed. The Run and Idle modes
may use any of the three available clock sources
(primary, secondary or internal oscillator block); the
Sleep mode does not use a clock source.
The power-managed modes include several
power-saving features offered on previous PIC®
microcontrollers. One is the clock switching feature,
offered in other PIC18 devices, allowing the controller
to use the Timer1 oscillator in place of the primary
oscillator. Also included is the Sleep mode, offered by
all PIC microcontrollers, where all device clocks are
stopped.
4.1
Selecting Power-Managed Modes
Selecting a power-managed mode requires two
decisions: if the CPU is to be clocked or not and which
clock source is to be used. The IDLEN bit
(OSCCON<7>) controls CPU clocking, while the
SCS<1:0> bits (OSCCON<1:0>) select the clock
source. The individual modes, bit settings, clock
sources and affected modules are summarized in
Table 4-1.
TABLE 4-1:
ENTERING POWER-MANAGED
MODES
Switching from one power-managed mode to another
begins by loading the OSCCON register. The
SCS<1:0> bits select the clock source and determine
which Run or Idle mode is to be used. Changing these
bits causes an immediate switch to the new clock
source, assuming that it is running. The switch may
also be subject to clock transition delays. These are
discussed in Section 4.1.3 “Clock Transitions and
Status Indicators” and subsequent sections.
Entry to the power-managed Idle or Sleep modes is
triggered by the execution of a SLEEP instruction. The
actual mode that results depends on the status of the
IDLEN bit.
Depending on the current mode and the mode being
switched to, a change to a power-managed mode does
not always require setting all of these bits. Many
transitions may be done by changing the oscillator
select bits, or changing the IDLEN bit, prior to issuing a
SLEEP instruction. If the IDLEN bit is already
configured correctly, it may only be necessary to
perform a SLEEP instruction to switch to the desired
mode.
POWER-MANAGED MODES
OSCCON bits
Mode
• the primary clock, as defined by the FOSC<1:0>
Configuration bits
• the secondary clock (Timer1 oscillator)
• the internal oscillator
Module Clocking
Available Clock and Oscillator Source
IDLEN<7>(1)
SCS<1:0>
CPU
Peripherals
0
N/A
Off
Off
PRI_RUN
N/A
10
Clocked
Clocked
SEC_RUN
N/A
01
Clocked
Clocked
Secondary – Timer1 Oscillator
RC_RUN
N/A
11
Clocked
Clocked
Internal Oscillator
PRI_IDLE
1
10
Off
Clocked
Primary – HS, EC
SEC_IDLE
1
01
Off
Clocked
Secondary – Timer1 Oscillator
RC_IDLE
1
11
Off
Clocked
Internal Oscillator
Sleep
Note 1:
None – All clocks are disabled
Primary – HS, EC;
this is the normal full-power execution mode
IDLEN reflects its value when the SLEEP instruction is executed.
© 2009 Microchip Technology Inc.
DS39682E-page 35
PIC18F45J10 FAMILY
4.1.3
CLOCK TRANSITIONS AND STATUS
INDICATORS
4.2.2
The SEC_RUN mode is the compatible mode to the
“clock switching” feature offered in other PIC18
devices. In this mode, the CPU and peripherals are
clocked from the Timer1 oscillator. This gives users the
option of lower power consumption while still using a
high-accuracy clock source.
The length of the transition between clock sources is
the sum of two cycles of the old clock source and three
to four cycles of the new clock source. This formula
assumes that the new clock source is stable.
Two bits indicate the current clock source and its
status:
OSTS
(OSCCON<3>)
and
T1RUN
(T1CON<6>). In general, only one of these bits will be
set while in a given power-managed mode. When the
OSTS bit is set, the primary clock is providing the
device clock. When the T1RUN bit is set, the Timer1
oscillator is providing the clock. If neither of these bits
is set, INTRC is clocking the device.
Note:
4.1.4
SEC_RUN mode is entered by setting the SCS<1:0>
bits to ‘01’. The device clock source is switched to the
Timer1 oscillator (see Figure 4-1), the primary
oscillator is shut down, the T1RUN bit (T1CON<6>) is
set and the OSTS bit is cleared.
Note:
Executing a SLEEP instruction does not
necessarily place the device into Sleep
mode. It acts as the trigger to place the
controller into either Sleep mode or one of
the Idle modes, depending on the setting
of the IDLEN bit.
MULTIPLE SLEEP COMMANDS
The power-managed mode that is invoked with the
SLEEP instruction is determined by the setting of the
IDLEN bit at the time the instruction is executed. If
another SLEEP instruction is executed, the device will
enter the power-managed mode specified by IDLEN at
that time. If IDLEN has changed, the device will enter the
new power-managed mode specified by the new setting.
4.2
The Timer1 oscillator should already be
running prior to entering SEC_RUN mode.
If the T1OSCEN bit is not set when the
SCS<1:0> bits are set to ‘01’, entry to
SEC_RUN mode will not occur. If the
Timer1 oscillator is enabled, but not yet
running, device clocks will be delayed until
the oscillator has started. In such situations, initial oscillator operation is far from
stable and unpredictable operation may
result.
On transitions from SEC_RUN mode to PRI_RUN
mode, the peripherals and CPU continue to be clocked
from the Timer1 oscillator while the primary clock is
started. When the primary clock becomes ready, a
clock switch back to the primary clock occurs (see
Figure 4-2). When the clock switch is complete, the
T1RUN bit is cleared, the OSTS bit is set and the
primary clock is providing the clock. The IDLEN and
SCS bits are not affected by the wake-up; the Timer1
oscillator continues to run.
Run Modes
In the Run modes, clocks to both the core and
peripherals are active. The difference between these
modes is the clock source.
4.2.1
SEC_RUN MODE
PRI_RUN MODE
The PRI_RUN mode is the normal, full-power execution mode of the microcontroller. This is also the default
mode upon a device Reset unless Two-Speed Start-up
is enabled (see Section 21.4 “Two-Speed Start-up”
for details). In this mode, the OSTS bit is set. (see
Section 3.6.1 “Oscillator Control Register”).
FIGURE 4-1:
TRANSITION TIMING FOR ENTRY TO SEC_RUN MODE
Q1 Q2 Q3 Q4 Q1
Q2
1
T1OSI
2
3
n-1
Q3
Q4
Q1
Q2
Q3
n
Clock Transition
OSC1
CPU
Clock
Peripheral
Clock
Program
Counter
DS39682E-page 36
PC
PC + 2
PC + 4
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
4.2.3
RC_RUN MODE
On transitions from RC_RUN mode to PRI_RUN mode,
the device continues to be clocked from the INTRC
while the primary clock is started. When the primary
clock becomes ready, a clock switch to the primary
clock occurs (see Figure 4-3). When the clock switch is
complete, the OSTS bit is set and the primary clock is
providing the device clock. The IDLEN and SCS bits
are not affected by the switch. The INTRC source will
continue to run if either the WDT or the Fail-Safe Clock
Monitor is enabled.
In RC_RUN mode, the CPU and peripherals are
clocked from the internal oscillator; the primary clock is
shut down. This mode provides the best power conservation of all the Run modes, while still executing code.
It works well for user applications which are not highly
timing-sensitive or do not require high-speed clocks at
all times.
This mode is entered by setting SCS<1:0> to ‘11’.
When the clock source is switched to the INTRC (see
Figure 4-2), the primary oscillator is shut down and the
OSTS bit is cleared.
FIGURE 4-2:
TRANSITION TIMING TO RC_RUN MODE
Q1 Q2 Q3 Q4 Q1
Q2
1
INTRC
2
3
n-1
Q3
Q4
Q1
Q2
Q3
n
Clock Transition
OSC1
CPU
Clock
Peripheral
Clock
Program
Counter
FIGURE 4-3:
PC
PC + 2
PC + 4
TRANSITION TIMING FROM RC_RUN MODE TO PRI_RUN MODE
Q1
Q2
Q3
Q4
Q2 Q3 Q4 Q1 Q2 Q3
Q1
INTRC
OSC1
TOST(1)
CPU Clock
Peripheral
Clock
Program
Counter
PC + 2
PC
SCS<1:0> bits Changed
PC + 4
OSTS bit Set
Note 1: TOST = 1024 TOSC. These intervals are not shown to scale.
© 2009 Microchip Technology Inc.
DS39682E-page 37
PIC18F45J10 FAMILY
4.3
Sleep Mode
4.4
The power-managed Sleep mode is identical to the
legacy Sleep mode offered in all other PIC microcontrollers. It is entered by clearing the IDLEN bit (the
default state on device Reset) and executing the
SLEEP instruction. This shuts down the selected
oscillator (Figure 4-4). All clock source status bits are
cleared.
Idle Modes
The Idle modes allow the controller’s CPU to be
selectively shut down while the peripherals continue to
operate. Selecting a particular Idle mode allows users
to further manage power consumption.
If the IDLEN bit is set to a ‘1’ when a SLEEP instruction is
executed, the peripherals will be clocked from the clock
source selected using the SCS<1:0> bits; however, the
CPU will not be clocked. The clock source status bits are
not affected. Setting IDLEN and executing a SLEEP
instruction provides a quick method of switching from a
given Run mode to its corresponding Idle mode.
Entering the Sleep mode from any other mode does not
require a clock switch. This is because no clocks are
needed once the controller has entered Sleep. If the
WDT is selected, the INTRC source will continue to
operate. If the Timer1 oscillator is enabled, it will also
continue to run.
If the WDT is selected, the INTRC source will continue
to operate. If the Timer1 oscillator is enabled, it will also
continue to run.
When a wake event occurs in Sleep mode (by interrupt,
Reset or WDT time-out), the device will not be clocked
until the clock source selected by the SCS<1:0> bits
becomes ready (see Figure 4-5), or it will be clocked
from the internal oscillator if either the Two-Speed
Start-up or the Fail-Safe Clock Monitor are enabled
(see Section 21.0 “Special Features of the CPU”). In
either case, the OSTS bit is set when the primary clock
is providing the device clocks. The IDLEN and SCS bits
are not affected by the wake-up.
Since the CPU is not executing instructions, the only
exits from any of the Idle modes are by interrupt, WDT
time-out or a Reset. When a wake event occurs, CPU
execution is delayed by an interval of TCSD
(parameter 38, Table 24-10) while it becomes ready to
execute code. When the CPU begins executing code,
it resumes with the same clock source for the current
Idle mode. For example, when waking from RC_IDLE
mode, the internal oscillator block will clock the CPU
and peripherals (in other words, RC_RUN mode). The
IDLEN and SCS bits are not affected by the wake-up.
While in any Idle mode or the Sleep mode, a WDT
time-out will result in a WDT wake-up to the Run mode
currently specified by the SCS<1:0> bits.
FIGURE 4-4:
TRANSITION TIMING FOR ENTRY TO SLEEP MODE
Q1 Q2 Q3 Q4 Q1
OSC1
CPU
Clock
Peripheral
Clock
Sleep
Program
Counter
PC
FIGURE 4-5:
PC + 2
TRANSITION TIMING FOR WAKE FROM SLEEP
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Q1
OSC1
TOST(1)
CPU Clock
Peripheral
Clock
Program
Counter
PC
Wake Event
PC + 2
PC + 4
PC + 6
OSTS bit Set
Note1: TOST = 1024 TOSC. These intervals are not shown to scale.
DS39682E-page 38
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
4.4.1
PRI_IDLE MODE
4.4.2
This mode is unique among the three low-power Idle
modes, in that it does not disable the primary device
clock. For timing-sensitive applications, this allows for
the fastest resumption of device operation with its more
accurate primary clock source, since the clock source
does not have to “warm up” or transition from another
oscillator.
PRI_IDLE mode is entered from PRI_RUN mode by
setting the IDLEN bit and executing a SLEEP instruction. If the device is in another Run mode, set IDLEN
first, then set the SCS<1:0> bits to ‘10’ and execute
SLEEP. Although the CPU is disabled, the peripherals
continue to be clocked from the primary clock source
specified by the FOSC0 Configuration bit. The OSTS
bit remains set (see Figure 4-6).
In SEC_IDLE mode, the CPU is disabled but the
peripherals continue to be clocked from the Timer1
oscillator. This mode is entered from SEC_RUN by setting the IDLEN bit and executing a SLEEP instruction. If
the device is in another Run mode, set IDLEN first, then
set SCS<1:0> to ‘01’ and execute SLEEP. When the
clock source is switched to the Timer1 oscillator, the
primary oscillator is shut-down, the OSTS bit is cleared
and the T1RUN bit is set.
When a wake event occurs, the peripherals continue to
be clocked from the Timer1 oscillator. After an interval
of TCSD following the wake event, the CPU begins executing code being clocked by the Timer1 oscillator. The
IDLEN and SCS bits are not affected by the wake-up;
the Timer1 oscillator continues to run (see Figure 4-7).
When a wake event occurs, the CPU is clocked from the
primary clock source. A delay of interval, TCSD, is
required between the wake event and when code
execution starts. This is required to allow the CPU to
become ready to execute instructions. After the
wake-up, the OSTS bit remains set. The IDLEN and
SCS bits are not affected by the wake-up (see
Figure 4-7).
FIGURE 4-6:
SEC_IDLE MODE
Note:
The Timer1 oscillator should already be
running prior to entering SEC_IDLE mode.
If the T1OSCEN bit is not set when the
SLEEP instruction is executed, the SLEEP
instruction will be ignored and entry to
SEC_IDLE mode will not occur. If the
Timer1 oscillator is enabled, but not yet
running, peripheral clocks will be delayed
until the oscillator has started. In such
situations, initial oscillator operation is far
from stable and unpredictable operation
may result.
TRANSITION TIMING FOR ENTRY TO IDLE MODE
Q1
Q3
Q2
Q4
Q1
OSC1
CPU Clock
Peripheral
Clock
Program
Counter
PC
FIGURE 4-7:
PC + 2
TRANSITION TIMING FOR WAKE FROM IDLE TO RUN MODE
Q1
Q2
Q3
Q4
OSC1
TCSD
CPU Clock
Peripheral
Clock
Program
Counter
PC
Wake Event
© 2009 Microchip Technology Inc.
DS39682E-page 39
PIC18F45J10 FAMILY
4.4.3
RC_IDLE MODE
In RC_IDLE mode, the CPU is disabled but the peripherals continue to be clocked from the internal oscillator.
This mode allows for controllable power conservation
during Idle periods.
From RC_RUN, this mode is entered by setting the
IDLEN bit and executing a SLEEP instruction. If the
device is in another Run mode, first set IDLEN, then
clear the SCS bits and execute SLEEP. When the clock
source is switched to the INTRC, the primary oscillator
is shut down and the OSTS bit is cleared.
When a wake event occurs, the peripherals continue to
be clocked from the INTRC. After a delay of TCSD
following the wake event, the CPU begins executing
code being clocked by the INTRC. The IDLEN and
SCS bits are not affected by the wake-up. The INTRC
source will continue to run if either the WDT or the
Fail-Safe Clock Monitor is enabled.
4.5
Exiting Idle and Sleep Modes
An exit from Sleep mode, or any of the Idle modes, is
triggered by an interrupt, a Reset or a WDT time-out.
This section discusses the triggers that cause exits
from power-managed modes. The clocking subsystem
actions are discussed in each of the power-managed
modes sections (see Section 4.2 “Run Modes”,
Section 4.3 “Sleep Mode” and Section 4.4 “Idle
Modes”).
4.5.1
EXIT BY INTERRUPT
Any of the available interrupt sources can cause the
device to exit from an Idle mode, or the Sleep mode, to
a Run mode. To enable this functionality, an interrupt
source must be enabled by setting its enable bit in one
of the INTCON or PIE registers. The exit sequence is
initiated when the corresponding interrupt flag bit is set.
On all exits from Idle or Sleep modes by interrupt, code
execution branches to the interrupt vector if the
GIE/GIEH bit (INTCON<7>) is set. Otherwise, code
execution continues or resumes without branching
(see Section 9.0 “Interrupts”).
4.5.2
EXIT BY WDT TIME-OUT
A WDT time-out will cause different actions depending
on which power-managed mode the device is in when
the time-out occurs.
If the device is not executing code (all Idle modes and
Sleep mode), the time-out will result in an exit from the
power-managed mode (see Section 4.2 “Run
Modes” and Section 4.3 “Sleep Mode”). If the device
is executing code (all Run modes), the time-out will
result in a WDT Reset (see Section 21.2 “Watchdog
Timer (WDT)”).
The WDT timer and postscaler are cleared by one of
the following events:
• executing a SLEEP or CLRWDT instruction
• the loss of a currently selected clock source (if the
Fail-Safe Clock Monitor is enabled)
4.5.3
EXIT BY RESET
Exiting an Idle or Sleep mode by Reset automatically
forces the device to run from the INTRC.
4.5.4
EXIT WITHOUT AN OSCILLATOR
START-UP DELAY
Certain exits from power-managed modes do not
invoke the OST at all. There are two cases:
• PRI_IDLE mode where the primary clock source
is not stopped; and
• the primary clock source is the EC mode.
In these instances, the primary clock source either
does not require an oscillator start-up delay, since it is
already running (PRI_IDLE), or normally does not
require an oscillator start-up delay (EC). However, a
fixed delay of interval, TCSD, following the wake event
is still required when leaving Sleep and Idle modes to
allow the CPU to prepare for execution. Instruction
execution resumes on the first clock cycle following this
delay.
A fixed delay of interval, TCSD, following the wake event
is required when leaving Sleep and Idle modes. This
delay is required for the CPU to prepare for execution.
Instruction execution resumes on the first clock cycle
following this delay.
DS39682E-page 40
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
5.0
RESET
5.1
The PIC18F45J10 family of devices differentiate
between various kinds of Reset:
a)
b)
c)
d)
e)
f)
g)
h)
i)
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during power-managed modes
Watchdog Timer (WDT) Reset (during
execution)
Configuration Mismatch (CM)
Brown-out Reset (BOR)
RESET Instruction
Stack Full Reset
Stack Underflow Reset
RCON Register
Device Reset events are tracked through the RCON
register (Register 5-1). The lower six bits of the register
indicate that a specific Reset event has occurred. In
most cases, these bits can only be set by the event and
must be cleared by the application after the event. The
state of these flag bits, taken together, can be read to
indicate the type of Reset that just occurred. This is
described in more detail in Section 5.7 “Reset State
of Registers”.
The RCON register also has a control bit for setting
interrupt priority (IPEN). Interrupt priority is discussed
in Section 9.0 “Interrupts”.
This section discusses Resets generated by MCLR,
POR and BOR and covers the operation of the various
start-up timers. Stack Reset events are covered in
Section 6.1.4.4 “Stack Full and Underflow Resets”.
WDT Resets are covered in Section 21.2 “Watchdog
Timer (WDT)”.
A simplified block diagram of the on-chip Reset circuit
is shown in Figure 5-1.
FIGURE 5-1:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
RESET Instruction
Configuration Word Mismatch
Stack
Pointer
Stack Full/Underflow Reset
External Reset
MCLR
( )_IDLE
Sleep
WDT
Time-out
VDD Rise
Detect
VDD
POR Pulse
Brown-out
Reset(1)
S
PWRT
32 μs
PWRT
INTRC
Note 1:
66 ms
11-Bit Ripple Counter
R
Q
Chip_Reset
The Brown-out Reset is not available in PIC18LF2XJ10/4XJ10 devices.
© 2009 Microchip Technology Inc.
DS39682E-page 41
PIC18F45J10 FAMILY
REGISTER 5-1:
RCON: RESET CONTROL REGISTER
R/W-0
U-0
R/W-1
R/W-1
R-1
R-1
R/W-0
R/W-0
IPEN
—
CM
RI
TO
PD
POR
BOR(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode)
bit 6
Unimplemented: Read as ‘0’
bit 5
CM: Configuration Mismatch Flag bit
1 = A Configuration Mismatch Reset has not occurred
0 = A Configuration Mismatch Reset has occurred (must be set in software after a Configuration
Mismatch Reset occurs)
bit 4
RI: RESET Instruction Flag bit
1 = The RESET instruction was not executed (set by firmware only)
0 = The RESET instruction was executed causing a device Reset (must be set in software after a
Brown-out Reset occurs)
bit 3
TO: Watchdog Time-out Flag bit
1 = Set by power-up, CLRWDT instruction or SLEEP instruction
0 = A WDT time-out occurred
bit 2
PD: Power-Down Detection Flag bit
1 = Set by power-up or by the CLRWDT instruction
0 = Set by execution of the SLEEP instruction
bit 1
POR: Power-on Reset Status bit
1 = A Power-on Reset has not occurred (set by firmware only)
0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs)
bit 0
BOR: Brown-out Reset Status bit(1)
1 = A Brown-out Reset has not occurred (set by firmware only)
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Note 1:
BOR is not available on PIC18LF2XJ10/4XJ10 devices.
Note 1: It is recommended that the POR bit be set after a Power-on Reset has been detected, so that subsequent
Power-on Resets may be detected.
2: If the on-chip voltage regulator is disabled, BOR remains ‘0’ at all times. See Section 5.4.1 “Detecting
BOR” for more information.
3: Brown-out Reset is said to have occurred when BOR is ‘0’ and POR is ‘1’ (assuming that POR was set to
‘1’ by software immediately after a Power-on Reset).
DS39682E-page 42
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
5.2
Master Clear (MCLR)
FIGURE 5-2:
The MCLR pin provides a method for triggering a hard
external Reset of the device. A Reset is generated by
holding the pin low. PIC18 extended microcontroller
devices have a noise filter in the MCLR Reset path
which detects and ignores small pulses.
5.3
D
C
Power-on Reset events are captured by the POR bit
(RCON<1>). The state of the bit is set to ‘0’ whenever
a Power-on Reset occurs; it does not change for any
other Reset event. POR is not reset to ‘1’ by any
hardware event. To capture multiple events, the user
manually resets the bit to ‘1’ in software following any
Power-on Reset.
5.4
Brown-out Reset (BOR)
(PIC18F2XJ10/4XJ10 Devices Only)
The PIC18F45J10 family of devices incorporates a
simple BOR function when the internal regulator is
enabled (ENVREG pin is tied to VDD). Any drop of VDD
below VBOR (parameter D005) for greater than time
TBOR (parameter 35) will reset the device. A Reset may
or may not occur if VDD falls below VBOR for less than
TBOR. The chip will remain in Brown-out Reset until
VDD rises above VBOR.
MCLR
PIC18F45J10
Note 1:
External Power-on Reset circuit is required
only if the VDD power-up slope is too slow.
The diode D helps discharge the capacitor
quickly when VDD powers down.
2:
R < 40 kΩ is recommended to make sure that
the voltage drop across R does not violate
the device’s electrical specification.
3:
R1 ≥ 1 kΩ will limit any current flowing into
MCLR from external capacitor C, in the event
of MCLR pin breakdown, due to Electrostatic
Discharge (ESD) or Electrical Overstress
(EOS).
To take advantage of the POR circuitry, tie the MCLR
pin through a resistor (1 kΩ to 10 kΩ) to VDD. This will
eliminate external RC components usually needed to
create a Power-on Reset delay. A minimum rise rate for
VDD is specified (parameter D004). For a slow rise
time, see Figure 5-2.
When the device starts normal operation (i.e., exits the
Reset condition), device operating parameters
(voltage, frequency, temperature, etc.) must be met to
ensure operation. If these conditions are not met, the
device must be held in Reset until the operating
conditions are met.
R
R1
Power-on Reset (POR)
A Power-on Reset condition is generated on-chip
whenever VDD rises above a certain threshold. This
allows the device to start in the initialized state when
VDD is adequate for operation.
VDD
VDD
The MCLR pin is not driven low by any internal Resets,
including the WDT.
EXTERNAL POWER-ON
RESET CIRCUIT (FOR
SLOW VDD POWER-UP)
5.4.1
DETECTING BOR
The BOR bit always resets to ‘0’ on any Brown-out
Reset or Power-on Reset event. This makes it difficult
to determine if a Brown-out Reset event has occurred
just by reading the state of BOR alone. A more reliable
method is to simultaneously check the state of both
POR and BOR. This assumes that the POR bit is reset
to ‘1’ in software immediately after any Power-on Reset
event. If BOR is ‘0’ while POR is ‘1’, it can be reliably
assumed that a Brown-out Reset event has occurred.
In devices designated with an “LF” part number (such
as PIC18LF25J10), Brown-out Reset functionality is
disabled. In this case, the BOR bit cannot be used to
determine a Brown-out Reset event. The BOR bit is still
cleared by a Power-on Reset event.
Once a BOR has occurred, the Power-up Timer will
keep the chip in Reset for TPWRT (parameter 33). If
VDD drops below VBOR while the Power-up Timer is
running, the chip will go back into a Brown-out Reset
and the Power-up Timer will be initialized. Once VDD
rises above VBOR, the Power-up Timer will execute the
additional time delay.
© 2009 Microchip Technology Inc.
DS39682E-page 43
PIC18F45J10 FAMILY
5.5
Configuration Mismatch (CM)
5.6
The Configuration Mismatch (CM) Reset is designed to
detect and attempt to recover from random, memory
corrupting events. These include Electrostatic Discharge
(ESD) events, which can cause widespread, single-bit
changes throughout the device and result in catastrophic
failure.
In PIC18FXXJ Flash devices, the device Configuration
registers (located in the configuration memory space)
are continuously monitored during operation by
comparing their values to complimentary shadow registers. If a mismatch is detected between the two sets
of registers, a CM Reset automatically occurs. These
events are captured by the CM bit (RCON<5>). The
state of the bit is set to ‘0’ whenever a CM event occurs;
it does not change for any other Reset event.
A CM Reset behaves similarly to a Master Clear Reset,
RESET instruction, WDT time-out or Stack Event
Resets. As with all hard and power Reset events, the
device Configuration Words are reloaded from the
Flash Configuration Words in program memory as the
device restarts.
Power-up Timer (PWRT)
PIC18F45J10 family devices incorporate an on-chip
Power-up Timer (PWRT) to help regulate the Power-on
Reset process. The PWRT is always enabled. The
main function is to ensure that the device voltage is
stable before code is executed.
The Power-up Timer (PWRT) of the PIC18F45J10
family devices is an 11-bit counter which uses the
INTRC source as the clock input. This yields an
approximate time interval of 2048 x 32 μs = 65.6 ms.
While the PWRT is counting, the device is held in
Reset.
The power-up time delay depends on the INTRC clock
and will vary from chip to chip due to temperature and
process variation. See DC parameter 33 for details.
5.6.1
TIME-OUT SEQUENCE
If enabled, the PWRT time-out is invoked after the POR
pulse has cleared. The total time-out will vary based on
the status of the PWRT. Figure 5-3, Figure 5-4,
Figure 5-5 and Figure 5-6 all depict time-out
sequences on power-up with the Power-up Timer
enabled.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the PWRT will expire. Bringing
MCLR high will begin execution immediately
(Figure 5-5). This is useful for testing purposes, or to
synchronize more than one PIC18F device operating in
parallel.
FIGURE 5-3:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD, VDD RISE < TPWRT)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
INTERNAL RESET
DS39682E-page 44
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 5-4:
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
INTERNAL RESET
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
FIGURE 5-5:
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
INTERNAL RESET
FIGURE 5-6:
SLOW RISE TIME (MCLR TIED TO VDD, VDD RISE > TPWRT)
3.3V
VDD
0V
1V
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
INTERNAL RESET
© 2009 Microchip Technology Inc.
DS39682E-page 45
PIC18F45J10 FAMILY
5.7
different Reset situations, as indicated in Table 5-1.
These bits are used in software to determine the nature
of the Reset.
Reset State of Registers
Most registers are unaffected by a Reset. Their status
is unknown on POR and unchanged by all other
Resets. The other registers are forced to a “Reset
state” depending on the type of Reset that occurred.
Table 5-2 describes the Reset states for all of the
Special Function Registers. These are categorized by
Power-on and Brown-out Resets, Master Clear and
WDT Resets and WDT wake-ups.
Most registers are not affected by a WDT wake-up,
since this is viewed as the resumption of normal
operation. Status bits from the RCON register (CM, RI,
TO, PD, POR and BOR) are set or cleared differently in
TABLE 5-1:
STATUS BITS, THEIR SIGNIFICANCE AND THE INITIALIZATION CONDITION FOR
RCON REGISTER
RCON Register
STKPTR Register
Program
Counter(1)
CM
RI
TO
PD
POR
Power-on Reset
0000h
1
1
1
1
0
0
0
0
RESET instruction
0000h
u
0
u
u
u
u
u
u
Brown-out Reset
0000h
1
1
1
1
u
0
u
u
Configuration Mismatch Reset
0000h
0
u
u
u
u
u
u
u
MCLR Reset during
power-managed Run modes
0000h
u
u
1
u
u
u
u
u
MCLR Reset during
power-managed Idle modes
and Sleep mode
0000h
u
u
1
0
u
u
u
u
MCLR Reset during full-power
execution
0000h
u
u
u
u
u
u
u
u
Stack Full Reset (STVREN = 1)
0000h
u
u
u
u
u
u
1
u
Stack Underflow Reset
(STVREN = 1)
0000h
u
u
u
u
u
u
u
1
Stack Underflow Error (not an
actual Reset, STVREN = 0)
0000h
u
u
u
u
u
u
u
1
WDT time-out during full-power
or power-managed Run modes
0000h
u
u
0
u
u
u
u
u
WDT time-out during
power-managed Idle or Sleep
modes
PC + 2
u
u
0
0
u
u
u
u
Interrupt exit from
power-managed modes
PC + 2
u
u
u
0
u
u
u
u
Condition
BOR(2) STKFUL
STKUNF
Legend: u = unchanged
Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
2: BOR is not available on PIC18LF2XJ10/4XJ10 devices.
DS39682E-page 46
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 5-2:
INITIALIZATION CONDITIONS FOR ALL REGISTERS
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruction,
Stack Resets,
CM Resets
TOSU
PIC18F2XJ10 PIC18F4XJ10
---0 0000
---0 0000
---0 uuuu(1)
TOSH
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu(1)
TOSL
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu(1)
STKPTR
PIC18F2XJ10 PIC18F4XJ10
00-0 0000
uu-0 0000
uu-u uuuu(1)
PCLATU
PIC18F2XJ10 PIC18F4XJ10
---0 0000
---0 0000
---u uuuu
PCLATH
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
PCL
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
TBLPTRU
PIC18F2XJ10 PIC18F4XJ10
--00 0000
--00 0000
--uu uuuu
TBLPTRH
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
TBLPTRL
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
TABLAT
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
PRODH
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
PRODL
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
INTCON
PIC18F2XJ10 PIC18F4XJ10
0000 000x
0000 000u
uuuu uuuu(3)
INTCON2
PIC18F2XJ10 PIC18F4XJ10
1111 -1-1
1111 -1-1
uuuu -u-u(3)
INTCON3
PIC18F2XJ10 PIC18F4XJ10
11-0 0-00
11-0 0-00
uu-u u-uu(3)
INDF0
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
Register
Wake-up via WDT
or Interrupt
PC + 2(2)
POSTINC0
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
POSTDEC0
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PREINC0
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PLUSW0
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
FSR0H
PIC18F2XJ10 PIC18F4XJ10
---- xxxx
---- uuuu
---- uuuu
FSR0L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
WREG
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
INDF1
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
POSTINC1
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
POSTDEC1
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PREINC1
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PLUSW1
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
FSR1H
PIC18F2XJ10 PIC18F4XJ10
---- xxxx
---- uuuu
---- uuuu
FSR1L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
BSR
PIC18F2XJ10 PIC18F4XJ10
---- 0000
---- 0000
---- uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the
hardware stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
© 2009 Microchip Technology Inc.
DS39682E-page 47
PIC18F45J10 FAMILY
TABLE 5-2:
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruction,
Stack Resets,
CM Resets
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
Register
INDF2
Wake-up via WDT
or Interrupt
N/A
POSTINC2
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
POSTDEC2
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PREINC2
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
PLUSW2
PIC18F2XJ10 PIC18F4XJ10
N/A
N/A
N/A
FSR2H
PIC18F2XJ10 PIC18F4XJ10
---- xxxx
---- uuuu
---- uuuu
FSR2L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
STATUS
PIC18F2XJ10 PIC18F4XJ10
---x xxxx
---u uuuu
---u uuuu
TMR0H
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
TMR0L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
T0CON
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
uuuu uuuu
OSCCON
PIC18F2XJ10 PIC18F4XJ10
0--- q-00
0--- q-00
u--- q-uu
WDTCON
PIC18F2XJ10 PIC18F4XJ10
---- ---0
---- ---0
---- ---u
(4)
RCON
PIC18F2XJ10 PIC18F4XJ10
0-11 11q0
0-qq qquu
u-uu qquu
TMR1H
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR1L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
T1CON
PIC18F2XJ10 PIC18F4XJ10
0000 0000
u0uu uuuu
uuuu uuuu
TMR2
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
PR2
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
1111 1111
T2CON
PIC18F2XJ10 PIC18F4XJ10
-000 0000
-000 0000
-uuu uuuu
SSP1BUF
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
SSP1ADD
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP1STAT
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP1CON1
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP1CON2
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
ADRESH
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADRESL
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADCON0
PIC18F2XJ10 PIC18F4XJ10
0-00 0000
0-00 0000
u-uu uuuu
ADCON1
PIC18F2XJ10 PIC18F4XJ10
--00 0qqq
--00 0qqq
--uu uqqq
ADCON2
PIC18F2XJ10 PIC18F4XJ10
0-00 0000
0-00 0000
u-uu uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the
hardware stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
DS39682E-page 48
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 5-2:
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruction,
Stack Resets,
CM Resets
CCPR1H
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR1L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP1CON
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
CCPR2H
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR2L
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP2CON
PIC18F2XJ10 PIC18F4XJ10
--00 0000
--00 0000
--uu uuuu
BAUDCON
PIC18F2XJ10 PIC18F4XJ10
01-0 0-00
01-0 0-00
uu-u u-uu
ECCP1DEL
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
ECCP1AS
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
CVRCON
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
CMCON
PIC18F2XJ10 PIC18F4XJ10
0000 0111
0000 0111
uuuu uuuu
SPBRGH
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SPBRG
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
RCREG
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
TXREG
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
TXSTA
PIC18F2XJ10 PIC18F4XJ10
0000 0010
0000 0010
uuuu uuuu
RCSTA
PIC18F2XJ10 PIC18F4XJ10
0000 000x
0000 000x
uuuu uuuu
EECON2
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
EECON1
PIC18F2XJ10 PIC18F4XJ10
---0 x00-
---0 x00-
---u uuu-
IPR3
PIC18F2XJ10 PIC18F4XJ10
11-- ----
11-- ----
uu-- ----
PIR3
PIC18F2XJ10 PIC18F4XJ10
00-- ----
00-- ----
uu-- ----(3)
PIE3
PIC18F2XJ10 PIC18F4XJ10
00-- ----
00-- ----
uu-- ----
IPR2
PIC18F2XJ10 PIC18F4XJ10
11-- 1--1
11-- 1--1
uu-- u--u
PIR2
PIC18F2XJ10 PIC18F4XJ10
00-- 0--0
00-- 0--0
uu-- u--u(3)
PIE2
PIC18F2XJ10 PIC18F4XJ10
00-- 0--0
00-- 0--0
uu-- u--u
IPR1
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
uuuu uuuu
PIR1
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu(3)
PIE1
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
Register
Wake-up via WDT
or Interrupt
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the
hardware stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
© 2009 Microchip Technology Inc.
DS39682E-page 49
PIC18F45J10 FAMILY
TABLE 5-2:
INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Applicable Devices
Power-on Reset,
Brown-out Reset
MCLR Resets,
WDT Reset,
RESET Instruction,
Stack Resets,
CM Resets
TRISE
PIC18F2XJ10 PIC18F4XJ10
0000 -111
1111 -111
uuuu -uuu
Register
Wake-up via WDT
or Interrupt
TRISD
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
uuuu uuuu
TRISC
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
uuuu uuuu
TRISB
PIC18F2XJ10 PIC18F4XJ10
1111 1111
1111 1111
uuuu uuuu
TRISA
PIC18F2XJ10 PIC18F4XJ10
--1- 1111
--1- 1111
--u- uuuu
SSP2BUF
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATE
PIC18F2XJ10 PIC18F4XJ10
---- -xxx
---- -uuu
---- -uuu
LATD
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATC
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATB
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
LATA
PIC18F2XJ10 PIC18F4XJ10
--xx xxxx
--uu uuuu
--uu uuuu
SSP2ADD
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP2STAT
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP2CON1
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
SSP2CON2
PIC18F2XJ10 PIC18F4XJ10
0000 0000
0000 0000
uuuu uuuu
PORTE
PIC18F2XJ10 PIC18F4XJ10
---- -xxx
---- -uuu
---- -uuu
PORTD
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTC
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTB
PIC18F2XJ10 PIC18F4XJ10
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTA
PIC18F2XJ10 PIC18F4XJ10
--0- 0000
--0- 0000
--u- uuuu
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Shaded cells indicate conditions do not apply for the designated device.
Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are
updated with the current value of the PC. The STKPTR is modified to point to the next location in the
hardware stack.
2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt
vector (0008h or 0018h).
3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up).
4: See Table 5-1 for Reset value for specific condition.
DS39682E-page 50
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.0
MEMORY ORGANIZATION
6.1
Program Memory Organization
PIC18 microcontrollers implement a 21-bit program
counter, which is capable of addressing a 2-Mbyte
program memory space. Accessing a location between
the upper boundary of the physically implemented
memory and the 2-Mbyte address will return all ‘0’s (a
NOP instruction).
There are two types of memory in PIC18 Enhanced
microcontroller devices:
• Program Memory
• Data RAM
As Harvard architecture devices, the data and program
memories use separate busses; this allows for
concurrent access of the two memory spaces.
The PIC18F24J10 and PIC18F44J10 each have
16 Kbytes of Flash memory and can store up to
8,192 single-word instructions. The PIC18F25J10 and
PIC18F45J10 each have 32 Kbytes of Flash memory
and can store up to 16,384 single-word instructions.
Additional detailed information on the operation of the
Flash program memory is provided in Section 7.0
“Flash Program Memory”.
PIC18 devices have two interrupt vectors. The Reset
vector address is at 0000h and the interrupt vector
addresses are at 0008h and 0018h.
The program memory map for the PIC18F45J10 family
devices is shown in Figure 6-1.
FIGURE 6-1:
PROGRAM MEMORY MAP AND STACK FOR PIC18F45J10 FAMILY DEVICES
PC<20:0>
CALL,RCALL,RETURN
RETFIE,RETLW
Stack Level 1
21
•
•
•
Stack Level 31
Reset Vector
0000h
High-Priority Interrupt Vector
0008h
Low-Priority Interrupt Vector
0018h
On-Chip
Program Memory
On-Chip
Program Memory
User Memory Space
3FF7h
4000h
PIC18FX4J10
7FF7h
8000h
PIC18FX5J10
Read ‘0’
Read ‘0’
1FFFFFh
200000h
© 2009 Microchip Technology Inc.
DS39682E-page 51
PIC18F45J10 FAMILY
6.1.1
HARD MEMORY VECTORS
6.1.2
FLASH CONFIGURATION WORDS
All PIC18 devices have a total of three hard-coded
return vectors in their program memory space. The
Reset vector address is the default value to which the
program counter returns on all device Resets; it is
located at 0000h.
Because PIC18F45J10 family devices do not have
persistent configuration memory, the top four words of
on-chip program memory are reserved for configuration
information. On Reset, the configuration information is
copied into the Configuration registers.
PIC18 devices also have two interrupt vector
addresses for the handling of high-priority and lowpriority interrupts. The high-priority interrupt vector is
located at 0008h and the low-priority interrupt vector is
at 0018h. Their locations in relation to the program
memory map are shown in Figure 6-2.
The Configuration Words are stored in their program
memory location in numerical order, starting with the
lower byte of CONFIG1 at the lowest address and ending with the upper byte of CONFIG4. For these devices,
only Configuration Words, CONFIG1 through
CONFIG3, are used; CONFIG4 is reserved. The actual
addresses of the Flash Configuration Word for devices
in the PIC18F45J10 family are shown in Table 6-1.
Their location in the memory map is shown with the
other memory vectors in Figure 6-2.
FIGURE 6-2:
HARD VECTOR AND
CONFIGURATION WORD
LOCATIONS FOR
PIC18F45J10 FAMILY
DEVICES
Reset Vector
0000h
High-Priority Interrupt Vector
0008h
Low-Priority Interrupt Vector
0018h
Additional details on the device Configuration Words
are provided in Section 21.1 “Configuration Bits”.
TABLE 6-1:
Device
PIC18F24J10
On-Chip
Program Memory
PIC18F44J10
PIC18F25J10
PIC18F45J10
Flash Configuration Words
FLASH CONFIGURATION
WORD FOR PIC18F45J10
FAMILY DEVICES
Program
Memory
(Kbytes)
Configuration
Word
Addresses
16
3FF8h to 3FFFh
32
7FF8h to 7FFFh
(Top of Memory-7)
(Top of Memory)
Read ‘0’
1FFFFFh
Legend:
(Top of Memory) represents upper boundary
of on-chip program memory space (see
Figure 6-1 for device-specific values).
Shaded area represents unimplemented
memory. Areas are not shown to scale.
DS39682E-page 52
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.1.3
PROGRAM COUNTER
The Program Counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 21 bits wide
and is contained in three separate 8-bit registers. The
low byte, known as the PCL register, is both readable
and writable. The high byte, or PCH register, contains
the PC<15:8> bits; it is not directly readable or writable.
Updates to the PCH register are performed through the
PCLATH register. The upper byte is called PCU. This
register contains the PC<20:16> bits; it is also not
directly readable or writable. Updates to the PCU
register are performed through the PCLATU register.
The contents of PCLATH and PCLATU are transferred
to the program counter by any operation that writes
PCL. Similarly, the upper two bytes of the program
counter are transferred to PCLATH and PCLATU by an
operation that reads PCL. This is useful for computed
offsets to the PC (see Section 6.1.6.1 “Computed
GOTO”).
The PC addresses bytes in the program memory. To
prevent the PC from becoming misaligned with word
instructions, the Least Significant bit of PCL is fixed to
a value of ‘0’. The PC increments by 2 to address
sequential instructions in the program memory.
The CALL, RCALL, GOTO and program branch
instructions write to the program counter directly. For
these instructions, the contents of PCLATH and
PCLATU are not transferred to the program counter.
6.1.4
RETURN ADDRESS STACK
The return address stack allows any combination of up
to 31 program calls and interrupts to occur. The PC is
pushed onto the stack when a CALL or RCALL instruction is executed or an interrupt is Acknowledged. The
PC value is pulled off the stack on a RETURN, RETLW
or RETFIE instruction. PCLATU and PCLATH are not
affected by any of the RETURN or CALL instructions.
FIGURE 6-3:
The stack operates as a 31-word by 21-bit RAM and a
5-bit Stack Pointer, STKPTR. The stack space is not
part of either program or data space. The Stack Pointer
is readable and writable and the address on the top of
the stack is readable and writable through the top-ofstack Special Function Registers. Data can also be
pushed to, or popped from the stack, using these
registers.
A CALL type instruction causes a push onto the stack;
the Stack Pointer is first incremented and the location
pointed to by the Stack Pointer is written with the
contents of the PC (already pointing to the instruction
following the CALL). A RETURN type instruction causes
a pop from the stack; the contents of the location
pointed to by the STKPTR are transferred to the PC
and then the Stack Pointer is decremented.
The Stack Pointer is initialized to ‘00000’ after all
Resets. There is no RAM associated with the location
corresponding to a Stack Pointer value of ‘00000’; this
is only a Reset value. Status bits indicate if the stack is
full or has overflowed or has underflowed.
6.1.4.1
Top-of-Stack Access
Only the top of the return address stack (TOS) is
readable and writable. A set of three registers,
TOSU:TOSH:TOSL, hold the contents of the stack location pointed to by the STKPTR register (Figure 6-3). This
allows users to implement a software stack if necessary.
After a CALL, RCALL or interrupt, the software can read
the pushed value by reading the TOSU:TOSH:TOSL
registers. These values can be placed on a user-defined
software stack. At return time, the software can return
these values to TOSU:TOSH:TOSL and do a return.
The user must disable the global interrupt enable bits
while accessing the stack to prevent inadvertent stack
corruption.
RETURN ADDRESS STACK AND ASSOCIATED REGISTERS
Return Address Stack<20:0>
11111
11110
11101
Top-of-Stack Registers
TOSU
00h
TOSH
1Ah
© 2009 Microchip Technology Inc.
STKPTR<4:0>
00010
TOSL
34h
Top-of-Stack
Stack Pointer
001A34h
000D58h
00011
00010
00001
00000
DS39682E-page 53
PIC18F45J10 FAMILY
6.1.4.2
Return Stack Pointer (STKPTR)
The STKPTR register (Register 6-1) contains the Stack
Pointer value, the STKFUL (Stack Overflow) status bit
and the STKUNF (Stack Underflow) status bits. The
value of the Stack Pointer can be 0 through 31. The
Stack Pointer increments before values are pushed
onto the stack and decrements after values are popped
off the stack. On Reset, the Stack Pointer value will be
zero. The user may read and write the Stack Pointer
value. This feature can be used by a Real-Time
Operating System (RTOS) for return stack
maintenance.
After the PC is pushed onto the stack 31 times (without
popping any values off the stack), the STKFUL bit is
set. The STKFUL bit is cleared by software or by a
POR.
The action that takes place when the stack becomes
full depends on the state of the STVREN (Stack Overflow Reset Enable) Configuration bit. (Refer to
Section 21.1 “Configuration Bits” for a description of
the device Configuration bits.) If STVREN is set
(default), the 31st push will push the (PC + 2) value
onto the stack, set the STKFUL bit and reset the
device. The STKFUL bit will remain set and the Stack
Pointer will be set to zero.
If STVREN is cleared, the STKFUL bit will be set on the
31st push and the Stack Pointer will increment to 31.
Any additional pushes will not overwrite the 31st push
and the STKPTR will remain at 31.
REGISTER 6-1:
When the stack has been popped enough times to
unload the stack, the next pop will return a value of zero
to the PC and sets the STKUNF bit, while the Stack
Pointer remains at zero. The STKUNF bit will remain
set until cleared by software or until a POR occurs.
Note:
6.1.4.3
Returning a value of zero to the PC on an
underflow has the effect of vectoring the
program to the Reset vector, where the
stack conditions can be verified and
appropriate actions can be taken. This is
not the same as a Reset, as the contents
of the SFRs are not affected.
PUSH and POP Instructions
Since the Top-of-Stack is readable and writable, the
ability to push values onto the stack and pull values off
the stack without disturbing normal program execution
is a desirable feature. The PIC18 instruction set
includes two instructions, PUSH and POP, that permit
the TOS to be manipulated under software control.
TOSU, TOSH and TOSL can be modified to place data
or a return address on the stack.
The PUSH instruction places the current PC value onto
the stack. This increments the Stack Pointer and loads
the current PC value onto the stack.
The POP instruction discards the current TOS by decrementing the Stack Pointer. The previous value pushed
onto the stack then becomes the TOS value.
STKPTR: STACK POINTER REGISTER
R/C-0
R/C-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
STKFUL(1)
STKUNF(1)
—
SP4
SP3
SP2
SP1
SP0
bit 7
bit 0
Legend:
C = Clearable bit
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
STKFUL: Stack Full Flag bit(1)
1 = Stack became full or overflowed
0 = Stack has not become full or overflowed
bit 6
STKUNF: Stack Underflow Flag bit(1)
1 = Stack underflow occurred
0 = Stack underflow did not occur
bit 5
Unimplemented: Read as ‘0’
bit 4-0
SP<4:0>: Stack Pointer Location bits
Note 1:
x = Bit is unknown
Bit 7 and bit 6 are cleared by user software or by a POR.
DS39682E-page 54
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.1.4.4
Stack Full and Underflow Resets
Device Resets on stack overflow and stack underflow
conditions are enabled by setting the STVREN bit in
Configuration Register 4L. When STVREN is set, a full
or underflow will set the appropriate STKFUL or
STKUNF bit and then cause a device Reset. When
STVREN is cleared, a full or underflow condition will set
the appropriate STKFUL or STKUNF bit but not cause
a device Reset. The STKFUL or STKUNF bits are
cleared by the user software or a Power-on Reset.
6.1.5
FAST REGISTER STACK
A Fast Register Stack is provided for the STATUS,
WREG and BSR registers, to provide a “fast return”
option for interrupts. The stack for each register is only
one level deep and is neither readable nor writable. It is
loaded with the current value of the corresponding
register when the processor vectors for an interrupt. All
interrupt sources will push values into the stack registers. The values in the registers are then loaded back
into their associated registers if the RETFIE, FAST
instruction is used to return from the interrupt.
6.1.6
LOOK-UP TABLES IN PROGRAM
MEMORY
There may be programming situations that require the
creation of data structures, or look-up tables, in
program memory. For PIC18 devices, look-up tables
can be implemented in two ways:
• Computed GOTO
• Table Reads
6.1.6.1
Computed GOTO
A computed GOTO is accomplished by adding an offset
to the program counter. An example is shown in
Example 6-2.
A look-up table can be formed with an ADDWF PCL
instruction and a group of RETLW nn instructions. The
W register is loaded with an offset into the table before
executing a call to that table. The first instruction of the
called routine is the ADDWF PCL instruction. The next
instruction executed will be one of the RETLW nn
instructions that returns the value ‘nn’ to the calling
function.
If both low and high-priority interrupts are enabled, the
stack registers cannot be used reliably to return from
low-priority interrupts. If a high-priority interrupt occurs
while servicing a low-priority interrupt, the stack register values stored by the low-priority interrupt will be
overwritten. In these cases, users must save the key
registers in software during a low-priority interrupt.
The offset value (in WREG) specifies the number of
bytes that the program counter should advance and
should be multiples of 2 (LSb = 0).
If interrupt priority is not used, all interrupts may use the
Fast Register Stack for returns from interrupt. If no
interrupts are used, the Fast Register Stack can be
used to restore the STATUS, WREG and BSR registers
at the end of a subroutine call. To use the Fast Register
Stack for a subroutine call, a CALL label, FAST
instruction must be executed to save the STATUS,
WREG and BSR registers to the Fast Register Stack. A
RETURN, FAST instruction is then executed to restore
these registers from the Fast Register Stack.
EXAMPLE 6-2:
Example 6-1 shows a source code example that uses
the Fast Register Stack during a subroutine call and
return.
EXAMPLE 6-1:
CALL SUB1, FAST
FAST REGISTER STACK
CODE EXAMPLE
;STATUS, WREG, BSR
;SAVED IN FAST REGISTER
;STACK
•
•
•
•
RETURN, FAST
SUB1
;RESTORE VALUES SAVED
;IN FAST REGISTER STACK
© 2009 Microchip Technology Inc.
In this method, only one data byte may be stored in
each instruction location and room on the return
address stack is required.
ORG
TABLE
6.1.6.2
MOVF
CALL
nn00h
ADDWF
RETLW
RETLW
RETLW
.
.
.
COMPUTED GOTO USING
AN OFFSET VALUE
OFFSET, W
TABLE
PCL
nnh
nnh
nnh
Table Reads and Table Writes
A better method of storing data in program memory
allows two bytes of data to be stored in each instruction
location.
Look-up table data may be stored two bytes per program word by using table reads and writes. The Table
Pointer (TBLPTR) register specifies the byte address
and the Table Latch (TABLAT) register contains the
data that is read from or written to program memory.
Data is transferred to or from program memory one
byte at a time.
Table read and table write operations are discussed
further in Section 7.1 “Table Reads and Table
Writes”.
DS39682E-page 55
PIC18F45J10 FAMILY
6.2
6.2.2
PIC18 Instruction Cycle
6.2.1
An “Instruction Cycle” consists of four Q cycles: Q1
through Q4. The instruction fetch and execute are
pipelined in such a manner that a fetch takes one
instruction cycle, while the decode and execute take
another instruction cycle. However, due to the pipelining, each instruction effectively executes in one
cycle. If an instruction causes the program counter to
change (e.g., GOTO), then two cycles are required to
complete the instruction (Example 6-3).
CLOCKING SCHEME
The microcontroller clock input, whether from an
internal or external source, is internally divided by four
to generate four non-overlapping quadrature clocks
(Q1, Q2, Q3 and Q4). Internally, the program counter is
incremented on every Q1; the instruction is fetched
from the program memory and latched into the instruction register during Q4. The instruction is decoded and
executed during the following Q1 through Q4. The
clocks and instruction execution flow are shown in
Figure 6-4.
FIGURE 6-4:
INSTRUCTION FLOW/PIPELINING
A fetch cycle begins with the Program Counter (PC)
incrementing in Q1.
In the execution cycle, the fetched instruction is latched
into the Instruction Register (IR) in cycle Q1. This
instruction is then decoded and executed during the
Q2, Q3 and Q4 cycles. Data memory is read during Q2
(operand read) and written during Q4 (destination
write).
CLOCK/INSTRUCTION CYCLE
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
OSC1
Q1
Q2
Internal
Phase
Clock
Q3
Q4
PC
PC
PC + 2
PC + 4
OSC2/CLKO
(RC mode)
Execute INST (PC – 2)
Fetch INST (PC)
EXAMPLE 6-3:
1. MOVLW 55h
4. BSF
Execute INST (PC + 2)
Fetch INST (PC + 4)
INSTRUCTION PIPELINE FLOW
TCY0
TCY1
Fetch 1
Execute 1
2. MOVWF PORTB
3. BRA
Execute INST (PC)
Fetch INST (PC + 2)
SUB_1
PORTA, BIT3 (Forced NOP)
5. Instruction @ address SUB_1
Fetch 2
TCY2
TCY3
TCY4
TCY5
Execute 2
Fetch 3
Execute 3
Fetch 4
Flush (NOP)
Fetch SUB_1 Execute SUB_1
All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction
is “flushed” from the pipeline while the new instruction is being fetched and then executed.
DS39682E-page 56
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.2.3
INSTRUCTIONS IN PROGRAM
MEMORY
The program memory is addressed in bytes. Instructions are stored as two bytes or four bytes in program
memory. The Least Significant Byte of an instruction
word is always stored in a program memory location
with an even address (LSB = 0). To maintain alignment
with instruction boundaries, the PC increments in steps
of 2 and the LSB will always read ‘0’ (see Section 6.1.3
“Program Counter”).
Figure 6-5 shows an example of how instruction words
are stored in the program memory.
FIGURE 6-5:
The CALL and GOTO instructions have the absolute program memory address embedded into the instruction.
Since instructions are always stored on word boundaries, the data contained in the instruction is a word
address. The word address is written to PC<20:1>,
which accesses the desired byte address in program
memory. Instruction #2 in Figure 6-5 shows how the
instruction, GOTO 0006h, is encoded in the program
memory. Program branch instructions, which encode a
relative address offset, operate in the same manner. The
offset value stored in a branch instruction represents the
number of single-word instructions that the PC will be
offset by. Section 22.0 “Instruction Set Summary”
provides further details of the instruction set.
INSTRUCTIONS IN PROGRAM MEMORY
LSB = 1
LSB = 0
0Fh
EFh
F0h
C1h
F4h
55h
03h
00h
23h
56h
Program Memory
Byte Locations →
6.2.4
Instruction 1:
Instruction 2:
MOVLW
GOTO
055h
0006h
Instruction 3:
MOVFF
123h, 456h
TWO-WORD INSTRUCTIONS
The standard PIC18 instruction set has four two-word
instructions: CALL, MOVFF, GOTO and LSFR. In all
cases, the second word of the instructions always has
‘1111’ as its four Most Significant bits; the other 12 bits
are literal data, usually a data memory address.
The use of ‘1111’ in the 4 MSbs of an instruction specifies a special form of NOP. If the instruction is executed
in proper sequence – immediately after the first word –
the data in the second word is accessed and used by
EXAMPLE 6-4:
Word Address
↓
000000h
000002h
000004h
000006h
000008h
00000Ah
00000Ch
00000Eh
000010h
000012h
000014h
the instruction sequence. If the first word is skipped for
some reason and the second word is executed by itself,
a NOP is executed instead. This is necessary for cases
when the two-word instruction is preceded by a conditional instruction that changes the PC. Example 6-4
shows how this works.
Note:
See Section 6.6 “PIC18 Instruction
Execution and the Extended Instruction Set” for information on two-word
instructions in the extended instruction set.
TWO-WORD INSTRUCTIONS
CASE 1:
Object Code
0110 0110 0000
1100 0001 0010
1111 0100 0101
0010 0100 0000
0000
0011
0110
0000
Source Code
TSTFSZ
REG1
; is RAM location 0?
MOVFF
REG1, REG2 ; No, skip this word
; Execute this word as a NOP
ADDWF
REG3
; continue code
0000
0011
0110
0000
Source Code
TSTFSZ
REG1
; is RAM location 0?
MOVFF
REG1, REG2 ; Yes, execute this word
; 2nd word of instruction
ADDWF
REG3
; continue code
CASE 2:
Object Code
0110 0110 0000
1100 0001 0010
1111 0100 0101
0010 0100 0000
© 2009 Microchip Technology Inc.
DS39682E-page 57
PIC18F45J10 FAMILY
6.3
Note:
Data Memory Organization
The operation of some aspects of data
memory are changed when the PIC18
extended instruction set is enabled. See
Section 6.5 “Data Memory and the
Extended Instruction Set” for more
information.
The data memory in PIC18 devices is implemented as
static RAM. Each register in the data memory has a
12-bit address, allowing up to 4096 bytes of data
memory. The memory space is divided into as many as
16 banks that contain 256 bytes each; PIC18F45J10
family devices implement all 16 banks. Figure 6-6
shows the data memory organization for the
PIC18F45J10 family devices.
The data memory contains Special Function Registers
(SFRs) and General Purpose Registers (GPRs). The
SFRs are used for control and status of the controller
and peripheral functions, while GPRs are used for data
storage and scratchpad operations in the user’s
application. Any read of an unimplemented location will
read as ‘0’s.
The instruction set and architecture allow operations
across all banks. The entire data memory may be
accessed by Direct, Indirect or Indexed Addressing
modes. Addressing modes are discussed later in this
subsection.
To ensure that commonly used registers (SFRs and
select GPRs) can be accessed in a single cycle, PIC18
devices implement an Access Bank. This is a 256-byte
memory space that provides fast access to SFRs and
the lower portion of GPR Bank 0 without using the
BSR. Section 6.3.2 “Access Bank” provides a
detailed description of the Access RAM.
6.3.1
BANK SELECT REGISTER (BSR)
Large areas of data memory require an efficient
addressing scheme to make rapid access to any
address possible. Ideally, this means that an entire
address does not need to be provided for each read or
write operation. For PIC18 devices, this is accomplished with a RAM banking scheme. This divides the
memory space into 16 contiguous banks of 256 bytes.
Depending on the instruction, each location can be
addressed directly by its full 12-bit address, or an 8-bit
low-order address and a 4-bit Bank Pointer.
Most instructions in the PIC18 instruction set make use
of the Bank Pointer, known as the Bank Select Register
(BSR). This SFR holds the 4 Most Significant bits of a
location’s address; the instruction itself includes the
8 Least Significant bits. Only the four lower bits of the
BSR are implemented (BSR<3:0>). The upper four bits
are unused; they will always read ‘0’ and cannot be
written to. The BSR can be loaded directly by using the
MOVLB instruction.
The value of the BSR indicates the bank in data
memory. The 8 bits in the instruction show the location
in the bank and can be thought of as an offset from the
bank’s lower boundary. The relationship between the
BSR’s value and the bank division in data memory is
shown in Figure 6-7.
Since up to 16 registers may share the same low-order
address, the user must always be careful to ensure that
the proper bank is selected before performing a data
read or write. For example, writing what should be
program data to an 8-bit address of F9h while the BSR
is 0Fh will end up resetting the program counter.
While any bank can be selected, only those banks that
are actually implemented can be read or written to.
Writes to unimplemented banks are ignored, while
reads from unimplemented banks will return ‘0’s. Even
so, the STATUS register will still be affected as if the
operation was successful. The data memory map in
Figure 6-6 indicates which banks are implemented.
In the core PIC18 instruction set, only the MOVFF
instruction fully specifies the 12-bit address of the
source and target registers. This instruction ignores the
BSR completely when it executes. All other instructions
include only the low-order address as an operand and
must use either the BSR or the Access Bank to locate
their target registers.
DS39682E-page 58
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 6-6:
DATA MEMORY MAP FOR PIC18F45J10 FAMILY DEVICES
BSR<3:0>
= 0000
= 0001
= 0010
= 0011
= 0100
= 0101
= 0110
= 0111
= 1000
= 1001
= 1010
= 1011
= 1100
= 1101
= 1110
= 1111
When ‘a’ = 0:
Data Memory Map
00h
Access RAM
FFh
00h
GPR
Bank 0
GPR
Bank 1
Bank 2
Bank 3
Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
Bank 9
000h
07Fh
080h
0FFh
100h
1FFh
200h
FFh
00h
2FFh
300h
GPR
FFh
00h
3FFh
400h
FFh
00h
4FFh
500h
FFh
00h
5FFh
600h
FFh
00h
6FFh
700h
7FFh
800h
FFh
00h
FFh
00h
Unused
Read 00h
FFh
00h
AFFh
B00h
FFh
00h
BFFh
C00h
FFh
Bank 13 00h
CFFh
D00h
FFh
00h
DFFh
E00h
Bank 12
Bank 14
FFh
00h
Unused
FFh
SFR
Bank 15
© 2009 Microchip Technology Inc.
The second 128 bytes are
Special Function Registers
(from Bank 15).
When ‘a’ = 1:
The BSR specifies the Bank
used by the instruction.
Access Bank
Access RAM Low
00h
7Fh
Access RAM High 80h
(SFRs)
FFh
8FFh
900h
9FFh
A00h
Bank 11
The first 128 bytes are
general purpose RAM
(from Bank 0).
GPR
FFh
00h
FFh
00h
Bank 10
The BSR is ignored and the
Access Bank is used.
EFFh
F00h
F7Fh
F80h
FFFh
DS39682E-page 59
PIC18F45J10 FAMILY
FIGURE 6-7:
USE OF THE BANK SELECT REGISTER (DIRECT ADDRESSING)
BSR(1)
7
0
0
0
0
0
0
0
Bank Select(2)
1
1
000h
Data Memory
Bank 0
100h
Bank 1
200h
300h
Bank 2
00h
7
FFh
00h
1
From Opcode(2)
1
1
1
1
1
0
1
1
FFh
00h
FFh
00h
Bank 3
through
Bank 13
E00h
Bank 14
F00h
FFFh
Note 1:
2:
6.3.2
Bank 15
FFh
00h
FFh
00h
FFh
The Access RAM bit of the instruction can be used to force an override of the selected bank (BSR<3:0>) to
the registers of the Access Bank.
The MOVFF instruction embeds the entire 12-bit address in the instruction.
ACCESS BANK
While the use of the BSR with an embedded 8-bit
address allows users to address the entire range of
data memory, it also means that the user must always
ensure that the correct bank is selected. Otherwise,
data may be read from or written to the wrong location.
This can be disastrous if a GPR is the intended target
of an operation but an SFR is written to instead.
Verifying and/or changing the BSR for each read or
write to data memory can become very inefficient.
To streamline access for the most commonly used data
memory locations, the data memory is configured with
an Access Bank, which allows users to access a
mapped block of memory without specifying a BSR.
The Access Bank consists of the first 128 bytes of
memory (00h-7Fh) in Bank 0 and the last 128 bytes of
memory (80h-FFh) in Block 15. The lower half is known
as the “Access RAM” and is composed of GPRs. This
upper half is also where the device’s SFRs are
mapped. These two areas are mapped contiguously in
the Access Bank and can be addressed in a linear
fashion by an 8-bit address (Figure 6-6).
The Access Bank is used by core PIC18 instructions
that include the Access RAM bit (the ‘a’ parameter in
the instruction). When ‘a’ is equal to ‘1’, the instruction
uses the BSR and the 8-bit address included in the
opcode for the data memory address. When ‘a’ is ‘0’,
DS39682E-page 60
however, the instruction is forced to use the Access
Bank address map; the current value of the BSR is
ignored entirely.
Using this “forced” addressing allows the instruction to
operate on a data address in a single cycle without
updating the BSR first. For 8-bit addresses of 80h and
above, this means that users can evaluate and operate
on SFRs more efficiently. The Access RAM below 80h
is a good place for data values that the user might need
to access rapidly, such as immediate computational
results or common program variables. Access RAM
also allows for faster and more code efficient context
saving and switching of variables.
The mapping of the Access Bank is slightly different
when the extended instruction set is enabled (XINST
Configuration bit = 1). This is discussed in more detail
in Section 6.5.3 “Mapping the Access Bank in
Indexed Literal Offset Mode”.
6.3.3
GENERAL PURPOSE REGISTER
FILE
PIC18 devices may have banked memory in the GPR
area. This is data RAM which is available for use by all
instructions. GPRs start at the bottom of Bank 0
(address 000h) and grow upwards towards the bottom of
the SFR area. GPRs are not initialized by a Power-on
Reset and are unchanged on all other Resets.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.3.4
SPECIAL FUNCTION REGISTERS
The SFRs can be classified into two sets: those
associated with the “core” device functionality (ALU,
Resets and interrupts) and those related to the peripheral functions. The Reset and Interrupt registers are
described in their respective chapters, while the ALU’s
STATUS register is described later in this section.
Registers related to the operation of a peripheral feature
are described in the chapter for that peripheral.
The Special Function Registers (SFRs) are registers
used by the CPU and peripheral modules for controlling
the desired operation of the device. These registers are
implemented as static RAM. SFRs start at the top of
data memory (FFFh) and extend downward to occupy
the top half of Bank 15 (F80h to FFFh). A list of these
registers is given in Table 6-2 and Table 6-3.
The SFRs are typically distributed among the
peripherals whose functions they control. Unused SFR
locations are unimplemented and read as ‘0’s.
TABLE 6-2:
Address
SPECIAL FUNCTION REGISTER MAP FOR PIC18F45J10 FAMILY DEVICES
Name
FFFh
Address
TOSU
FDFh
Name
INDF2
Address
(1)
FBFh
PIR1
PIE1
CCPR2H
F9Ch
—(2)
FBBh
CCPR2L
F9Bh
—(2)
FBAh
CCP2CON
F9Ah
—(2)
F99h
—(2)
FDCh
FBCh
FDDh POSTDEC2(1)
STKPTR
F9Eh
F9Dh
PREINC2(1)
FDEh POSTINC2
TOSL
FFCh
CCPR1L
CCP1CON
FBEh
TOSH
FFBh
PCLATU
FDBh
PLUSW2(1)
FFAh
PCLATH
FDAh
FSR2H
Name
IPR1
FBDh
FFEh
CCPR1H
Address
F9Fh
(1)
FFDh
Name
FF9h
PCL
FD9h
FSR2L
FB9h
—(2)
FF8h
TBLPTRU
FD8h
STATUS
FB8h
BAUDCON
F98h
—(2)
F97h
—(2)
FF7h
TBLPTRH
FD7h
TMR0H
FB7h
ECCP1DEL(3)
FF6h
TBLPTRL
FD6h
TMR0L
FB6h
ECCP1AS(3)
F96h
TRISE(3)
FF5h
TABLAT
FD5h
T0CON
FB5h
CVRCON
F95h
TRISD(3)
FF4h
PRODH
FD4h
—(2)
FB4h
CMCON
F94h
TRISC
FF3h
PRODL
FD3h
OSCCON
FB3h
—(2)
F93h
TRISB
FF2h
INTCON
FD2h
—(2)
FB2h
—(2)
F92h
TRISA
FF1h
INTCON2
FD1h
WDTCON
FB1h
—(2)
F91h
—(2)
FF0h
INTCON3
FD0h
RCON
FB0h
SPBRGH
F90h
—(2)
FEFh
INDF0(1)
FCFh
TMR1H
FAFh
SPBRG
F8Fh
—(2)
FEEh POSTINC0(1)
FCEh
TMR1L
FAEh
RCREG
F8Eh
SSP2BUF
FEDh POSTDEC0(1)
FCDh
T1CON
FADh
TXREG
F8Dh
LATE(3)
FECh
PREINC0(1)
FCCh
TMR2
FACh
TXSTA
F8Ch
LATD(3)
FEBh
(1)
FCBh
PR2
FABh
RCSTA
F8Bh
LATC
PLUSW0
FEAh
FSR0H
FCAh
T2CON
FAAh
—(2)
F8Ah
LATB
FE9h
FSR0L
FC9h
SSP1BUF
FA9h
—(2)
F89h
LATA
FA8h
—(2)
F88h
SSP2ADD(3)
F87h SSP2STAT(3)
FE8h
WREG
FE7h
INDF1(1)
FC8h
SSP1ADD
FC7h
SSP1STAT
FA7h
EECON2(1)
FE6h POSTINC1(1)
FC6h
SSP1CON1
FA6h
EECON1
F86h SSP2CON1(3)
FE5h
POSTDEC1(1)
FC5h
SSP1CON2
FA5h
IPR3
F85h SSP2CON2(3)
FE4h
PREINC1(1)
FC4h
ADRESH
FA4h
PIR3
F84h
PORTE(3)
FE3h
(1)
PLUSW1
FC3h
ADRESL
FA3h
PIE3
F83h
PORTD(3)
FE2h
FSR1H
FC2h
ADCON0
FA2h
IPR2
F82h
PORTC
FE1h
FSR1L
FC1h
ADCON1
FA1h
PIR2
F81h
PORTB
FE0h
BSR
FC0h
ADCON2
FA0h
PIE2
F80h
PORTA
Note 1:
2:
3:
This is not a physical register.
Unimplemented registers are read as ‘0’.
This register is not available in 28-pin devices.
© 2009 Microchip Technology Inc.
DS39682E-page 61
PIC18F45J10 FAMILY
TABLE 6-3:
File Name
TOSU
REGISTER FILE SUMMARY (PIC18F24J10/25J10/44J10/45J10)
Bit 7
Bit 6
Bit 5
—
—
—
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Details
on page:
---0 0000
47, 53
TOSH
Top-of-Stack High Byte (TOS<15:8>)
0000 0000
47, 53
TOSL
Top-of-Stack Low Byte (TOS<7:0>)
0000 0000
47, 53
STKPTR
PCLATU
Top-of-Stack Upper Byte (TOS<20:16>)
Value on
POR, BOR
STKFUL
STKUNF
—
Return Stack Pointer
00-0 0000
47, 54
—
—
—
Holding Register for PC<20:16>
---0 0000
47, 53
PCLATH
Holding Register for PC<15:8>
0000 0000
47, 53
PCL
PC Low Byte (PC<7:0>)
0000 0000
47, 53
--00 0000
47, 74
TBLPTRU
—
—
bit 21
Program Memory Table Pointer Upper Byte (TBLPTR<20:16>)
TBLPTRH
Program Memory Table Pointer High Byte (TBLPTR<15:8>)
0000 0000
47, 74
TBLPTRL
Program Memory Table Pointer Low Byte (TBLPTR<7:0>)
0000 0000
47, 74
TABLAT
Program Memory Table Latch
0000 0000
47, 74
PRODH
Product Register High Byte
xxxx xxxx
47, 81
PRODL
Product Register Low Byte
xxxx xxxx
47, 81
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
47, 85
INTCON2
RBPU
INTEDG0
INTEDG1
INTEDG2
—
TMR0IP
—
RBIP
1111 -1-1
47, 86
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
11-0 0-00
47, 87
N/A
47, 67
INTCON3
INDF0
Uses contents of FSR0 to address data memory – value of FSR0 not changed (not a physical register)
POSTINC0
Uses contents of FSR0 to address data memory – value of FSR0 post-incremented (not a physical register)
N/A
47, 67
POSTDEC0
Uses contents of FSR0 to address data memory – value of FSR0 post-decremented (not a physical register)
N/A
47, 67
PREINC0
Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register)
N/A
47, 67
PLUSW0
Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) –
value of FSR0 offset by W
N/A
47, 67
FSR0H
---- xxxx
47, 67
FSR0L
Indirect Data Memory Address Pointer 0 Low Byte
—
—
—
—
Indirect Data Memory Address Pointer 0 High Byte
xxxx xxxx
47, 67
WREG
Working Register
xxxx xxxx
47
INDF1
Uses contents of FSR1 to address data memory – value of FSR1 not changed (not a physical register)
N/A
47, 67
POSTINC1
Uses contents of FSR1 to address data memory – value of FSR1 post-incremented (not a physical register)
N/A
47, 67
POSTDEC1
Uses contents of FSR1 to address data memory – value of FSR1 post-decremented (not a physical register)
N/A
47, 67
PREINC1
Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register)
N/A
47, 67
PLUSW1
Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) –
value of FSR1 offset by W
N/A
47, 67
---- xxxx
47, 67
FSR1H
—
FSR1L
—
—
—
Indirect Data Memory Address Pointer 1 High Byte
Indirect Data Memory Address Pointer 1 Low Byte
BSR
—
—
—
—
Bank Select Register
xxxx xxxx
47, 67
---- 0000
47, 58
48, 67
INDF2
Uses contents of FSR2 to address data memory – value of FSR2 not changed (not a physical register)
N/A
POSTINC2
Uses contents of FSR2 to address data memory – value of FSR2 post-incremented (not a physical register)
N/A
48, 67
POSTDEC2
Uses contents of FSR2 to address data memory – value of FSR2 post-decremented (not a physical register)
N/A
48, 67
PREINC2
Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register)
N/A
48, 67
PLUSW2
Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) –
value of FSR2 offset by W
N/A
48, 67
---- xxxx
48, 67
FSR2H
—
FSR2L
—
—
—
Indirect Data Memory Address Pointer 2 High Byte
Indirect Data Memory Address Pointer 2 Low Byte
STATUS
Legend:
Note 1:
2:
3:
—
—
—
N
OV
Z
DC
C
xxxx xxxx
48, 67
---x xxxx
48, 65
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition
See Section 5.4 “Brown-out Reset (BOR) (PIC18F2XJ10/4XJ10 Devices Only)”.
These registers and/or bits are not implemented on 28-pin devices and are read as ‘0’. Reset values are shown for 40/44-pin devices;
individual unimplemented bits should be interpreted as ‘-’.
Alternate names and definitions for these bits when the MSSP module is operating in I2C™ Slave mode. See Section 16.4.3.2 “Address
Masking” for details.
DS39682E-page 62
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 6-3:
File Name
REGISTER FILE SUMMARY (PIC18F24J10/25J10/44J10/45J10) (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Details
on page:
TMR0H
Timer0 Register High Byte
0000 0000
48, 117
TMR0L
Timer0 Register Low Byte
xxxx xxxx
48, 117
48, 115
T0CON
TMR0ON
T08BIT
T0CS
T0SE
PSA
T0PS2
T0PS1
T0PS0
1111 1111
OSCCON
IDLEN
—
—
—
OSTS
—
SCS1
SCS0
0--- q-00
32, 48
WDTCON
—
—
—
—
—
—
—
SWDTEN
--- ---0
48, 242
IPEN
—
CM
RI
TO
PD
POR
BOR(1)
RCON
0-11 11q0 42, 46, 94
TMR1H
Timer1 Register High Byte
xxxx xxxx
48, 124
TMR1L
Timer1 Register Low Byte
xxxx xxxx
48, 124
T1CON
RD16
T1RUN
TMR2
Timer2 Register
PR2
Timer2 Period Register
T2CON
—
T2OUTPS3
T1CKPS1
T2OUTPS2
T1CKPS0
T2OUTPS1
T1OSCEN
T2OUTPS0
T1SYNC
TMR2ON
TMR1CS
T2CKPS1
TMR1ON
T2CKPS0
0000 0000
48, 119
0000 0000
48, 126
1111 1111
48, 126
-000 0000
48, 125
48, 158
SSP1BUF
MSSP1 Receive Buffer/Transmit Register
xxxx xxxx
SSP1ADD
MSSP1 Address Register in I2C™ Slave mode. MSSP1 Baud Rate Reload Register in I2C Master mode.
0000 0000
48, 159
SSP1STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000
48, 150,
160
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
48, 151,
161
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
0000 0000
48, 162
GCEN
ACKSTAT
ADMSK5(3)
ADMSK4(3)
ADMSK3(3)
ADMSK2(3)
ADMSK1(3)
SEN
0000 0000
48, 163
SSP1CON2
ADRESH
A/D Result Register High Byte
xxxx xxxx
48, 223
ADRESL
A/D Result Register Low Byte
xxxx xxxx
48, 223
ADCON0
ADCAL
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
0-00 0000
48, 218
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
--00 0qqq
48, 218
ADFM
—
ACQT2
ACQT1
ACQT0
ADCS2
ADCS1
ADCS0
ADCON2
0-00 0000
48, 218
CCPR1H
Capture/Compare/PWM Register 1 High Byte
xxxx xxxx
49, 128
CCPR1L
Capture/Compare/PWM Register 1 Low Byte
xxxx xxxx
49, 128
0000 0000
49, 128,
49, 128
CCP1CON
P1M1(2)
P1M0(2)
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
CCPR2H
Capture/Compare/PWM Register 2 High Byte
xxxx xxxx
CCPR2L
Capture/Compare/PWM Register 2 Low Byte
xxxx xxxx
49, 128
--00 0000
49, 128
CCP2CON
—
BAUDCON
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
01-0 0-00
49, 196
ECCP1DEL
PRSEN
PDC6(2)
PDC5(2)
PDC4(2)
PDC3(2)
PDC2(2)
PDC1(2)
PDC0(2)
0000 0000
49, 144
ECCP1AS
ECCPASE
ECCPAS2
ECCPAS1
ECCPAS0
PSSAC1
PSSAC0
PSSBD1(2)
PSSBD0(2) 0000 0000
49, 146
CVRCON
CVREN
CVROE
CVRR
CVRSS
CVR3
CVR2
CVR1
CVR0
0000 0000
49, 232
CMCON
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
0000 0111
49, 226
Legend:
Note 1:
2:
3:
—
DC2B1
DC2B0
CCP2M3
CCP2M2
CCP2M1
CCP2M0
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition
See Section 5.4 “Brown-out Reset (BOR) (PIC18F2XJ10/4XJ10 Devices Only)”.
These registers and/or bits are not implemented on 28-pin devices and are read as ‘0’. Reset values are shown for 40/44-pin devices;
individual unimplemented bits should be interpreted as ‘-’.
Alternate names and definitions for these bits when the MSSP module is operating in I2C™ Slave mode. See Section 16.4.3.2 “Address
Masking” for details.
© 2009 Microchip Technology Inc.
DS39682E-page 63
PIC18F45J10 FAMILY
TABLE 6-3:
File Name
REGISTER FILE SUMMARY (PIC18F24J10/25J10/44J10/45J10) (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Details
on page:
SPBRGH
EUSART Baud Rate Generator Register High Byte
0000 0000
49, 198
SPBRG
EUSART Baud Rate Generator Register Low Byte
0000 0000
49, 198
RCREG
EUSART Receive Register
0000 0000
49, 205
TXREG
EUSART Transmit Register
xxxx xxxx
49, 203
TXSTA
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
49, 196
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
49, 195
EECON2
EECON1
EEPROM Control Register 2 (not a physical register)
0000 0000
49, 72
—
—
—
FREE
WRERR
WREN
WR
—
---0 x00-
49, 74
IPR3
SSP2IP
BCL2IP
—
—
—
—
—
—
11-- ----
49, 94
PIR3
SSP2IF
BCL2IF
—
—
—
—
—
—
00-- ----
49, 90
PIE3
SSP2IE
BCL2IE
—
—
—
—
—
—
00-- ----
49, 92
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
11-- 1--1
49, 93
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
00-- 0--0
49, 89
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
00-- 0--0
49, 91
IPR1
PSPIP(2)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
1111 1111
49, 92
PIR1
PSPIF(2)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
0000 0000
49, 88
PIE1
PSPIE(2)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
0000 0000
49, 91
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
0000 -111
50, 112
TRISE(2)
TRISD(2)
PORTD Data Direction Control Register
1111 1111
50, 107
TRISC
PORTC Data Direction Control Register
1111 1111
50, 104
TRISB
PORTB Data Direction Control Register
1111 1111
50, 101
TRISA
—
SSP2BUF
LATE(2)
—
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
MSSP2 Receive Buffer/Transmit Register
—
—
—
—
—
PORTE Data Latch Register
(Read and Write to Data Latch)
--1- 1111
50, 98
xxxx xxxx
50, 158
---- -xxx
50, 110
LATD(2)
PORTD Data Latch Register (Read and Write to Data Latch)
xxxx xxxx
50, 107
LATC
PORTC Data Latch Register (Read and Write to Data Latch)
xxxx xxxx
50, 104
LATB
PORTB Data Latch Register (Read and Write to Data Latch)
xxxx xxxx
50, 101
LATA
—
SSP2ADD
—
PORTA Data Latch Register (Read and Write to Data Latch)
MSSP2 Address Register in I2C™ Slave mode. MSSP2 Baud Rate Reload Register in I2C Master mode.
--xx xxxx
50, 98
0000 0000
50, 158
SSP2STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000
50, 150,
160
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
50, 151,
161
SSP2CON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
0000 0000
50, 164
GCEN
ACKSTAT
ADMSK5(3)
ADMSK4(3)
ADMSK3(3)
ADMSK2(3)
ADMSK1(3)
SEN
0000 0000
48, 163
PORTE(2)
—
—
—
—
—
RE2(2)
RE1(2)
RE0(2)
---- -xxx
50, 110
PORTD(2)
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
xxxx xxxx
50, 107
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx
50, 104
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
50, 101
PORTA
—
—
RA5
—
RA3
RA2
RA1
RA0
--0- 0000
50, 98
Legend:
Note 1:
2:
3:
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition
See Section 5.4 “Brown-out Reset (BOR) (PIC18F2XJ10/4XJ10 Devices Only)”.
These registers and/or bits are not implemented on 28-pin devices and are read as ‘0’. Reset values are shown for 40/44-pin devices;
individual unimplemented bits should be interpreted as ‘-’.
Alternate names and definitions for these bits when the MSSP module is operating in I2C™ Slave mode. See Section 16.4.3.2 “Address
Masking” for details.
DS39682E-page 64
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.3.5
STATUS REGISTER
The STATUS register, shown in Register 6-2, contains
the arithmetic status of the ALU. As with any other SFR,
it can be the operand for any instruction.
If the STATUS register is the destination for an instruction that affects the Z, DC, C, OV or N bits, the results
of the instruction are not written; instead, the STATUS
register is updated according to the instruction
performed. Therefore, the result of an instruction with
the STATUS register as its destination may be different
than intended. As an example, CLRF STATUS will set
the Z bit and leave the remaining Status bits
unchanged (‘000u u1uu’).
REGISTER 6-2:
U-0
For other instructions that do not affect Status bits, see
the instruction set summaries in Table 22-2 and
Table 22-3.
Note:
The C and DC bits operate as the borrow
and digit borrow bits, respectively, in
subtraction.
STATUS REGISTER
U-0
—
It is recommended that only BCF, BSF, SWAPF, MOVFF
and MOVWF instructions are used to alter the STATUS
register, because these instructions do not affect the Z,
C, DC, OV or N bits in the STATUS register.
U-0
—
—
R/W-x
N
R/W-x
R/W-x
OV
Z
R/W-x
R/W-x
(1)
C(2)
DC
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-5
Unimplemented: Read as ‘0’
bit 4
N: Negative bit
This bit is used for signed arithmetic (2’s complement). It indicates whether the result was negative
(ALU MSB = 1).
1 = Result was negative
0 = Result was positive
bit 3
OV: Overflow bit
This bit is used for signed arithmetic (2’s complement). It indicates an overflow of the 7-bit magnitude
which causes the sign bit (bit 7) to change state.
1 = Overflow occurred for signed arithmetic (in this arithmetic operation)
0 = No overflow occurred
bit 2
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1
DC: Digit Carry/Borrow bit(1)
For ADDWF, ADDLW, SUBLW and SUBWF instructions:
1 = A carry-out from the 4th low-order bit of the result occurred
0 = No carry-out from the 4th low-order bit of the result
bit 0
C: Carry/Borrow bit(2)
For ADDWF, ADDLW, SUBLW and SUBWF instructions:
1 = A carry-out from the Most Significant bit of the result occurred
0 = No carry-out from the Most Significant bit of the result occurred
Note 1:
2:
For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second
operand. For rotate (RRF, RLF) instructions, this bit is loaded with either bit 4 or bit 3 of the source register.
For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second
operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low-order bit of the
source register.
© 2009 Microchip Technology Inc.
DS39682E-page 65
PIC18F45J10 FAMILY
6.4
Data Addressing Modes
Note:
The execution of some instructions in the
core PIC18 instruction set are changed
when the PIC18 extended instruction set is
enabled. See Section 6.5 “Data Memory
and the Extended Instruction Set” for
more information.
While the program memory can be addressed in only
one way – through the program counter – information
in the data memory space can be addressed in several
ways. For most instructions, the addressing mode is
fixed. Other instructions may use up to three modes,
depending on which operands are used and whether or
not the extended instruction set is enabled.
The addressing modes are:
•
•
•
•
Inherent
Literal
Direct
Indirect
INHERENT AND LITERAL
ADDRESSING
Many PIC18 control instructions do not need any
argument at all; they either perform an operation that
globally affects the device or they operate implicitly on
one register. This addressing mode is known as Inherent
Addressing. Examples include SLEEP, RESET and DAW.
Other instructions work in a similar way but require an
additional explicit argument in the opcode. This is
known as Literal Addressing mode because they
require some literal value as an argument. Examples
include ADDLW and MOVLW, which respectively, add or
move a literal value to the W register. Other examples
include CALL and GOTO, which include a 20-bit
program memory address.
6.4.2
A few instructions, such as MOVFF, include the entire
12-bit address (either source or destination) in their
opcodes. In these cases, the BSR is ignored entirely.
The destination of the operation’s results is determined
by the destination bit ‘d’. When ‘d’ is ‘1’, the results are
stored back in the source register, overwriting its original contents. When ‘d’ is ‘0’, the results are stored in
the W register. Instructions without the ‘d’ argument
have a destination that is implicit in the instruction; their
destination is either the target register being operated
on or the W register.
6.4.3
An additional addressing mode, Indexed Literal Offset,
is available when the extended instruction set is
enabled (XINST Configuration bit = 1). Its operation is
discussed in greater detail in Section 6.5.1 “Indexed
Addressing with Literal Offset”.
6.4.1
The Access RAM bit ‘a’ determines how the address is
interpreted. When ‘a’ is ‘1’, the contents of the BSR
(Section 6.3.1 “Bank Select Register (BSR)”) are
used with the address to determine the complete 12-bit
address of the register. When ‘a’ is ‘0’, the address is
interpreted as being a register in the Access Bank.
Addressing that uses the Access RAM is sometimes
also known as Direct Forced Addressing mode.
DIRECT ADDRESSING
Direct Addressing specifies all or part of the source
and/or destination address of the operation within the
opcode itself. The options are specified by the
arguments accompanying the instruction.
INDIRECT ADDRESSING
Indirect Addressing allows the user to access a location
in data memory without giving a fixed address in the
instruction. This is done by using File Select Registers
(FSRs) as pointers to the locations to be read or written
to. Since the FSRs are themselves located in RAM as
Special Function Registers, they can also be directly
manipulated under program control. This makes FSRs
very useful in implementing data structures, such as
tables and arrays in data memory.
The registers for Indirect Addressing are also
implemented with Indirect File Operands (INDFs) that
permit automatic manipulation of the pointer value with
auto-incrementing, auto-decrementing or offsetting
with another value. This allows for efficient code, using
loops, such as the example of clearing an entire RAM
bank in Example 6-5.
EXAMPLE 6-5:
NEXT
LFSR
CLRF
BTFSS
BRA
CONTINUE
HOW TO CLEAR RAM
(BANK 1) USING
INDIRECT ADDRESSING
FSR0, 100h ;
POSTINC0
; Clear INDF
; register then
; inc pointer
FSR0H, 1
; All done with
; Bank1?
NEXT
; NO, clear next
; YES, continue
In the core PIC18 instruction set, bit-oriented and byteoriented instructions use some version of Direct
Addressing by default. All of these instructions include
some 8-bit literal address as their Least Significant
Byte. This address specifies either a register address in
one of the banks of data RAM (Section 6.3.3 “General
Purpose Register File”) or a location in the Access
Bank (Section 6.3.2 “Access Bank”) as the data
source for the instruction.
DS39682E-page 66
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
6.4.3.1
FSR Registers and the INDF
Operand
6.4.3.2
At the core of Indirect Addressing are three sets of registers: FSR0, FSR1 and FSR2. Each represents a pair
of 8-bit registers, FSRnH and FSRnL. The four upper
bits of the FSRnH register are not used, so each FSR
pair holds a 12-bit value. This represents a value that
can address the entire range of the data memory in a
linear fashion. The FSR register pairs, then, serve as
pointers to data memory locations.
In addition to the INDF operand, each FSR register pair
also has four additional indirect operands. Like INDF,
these are “virtual” registers that cannot be indirectly
read or written to. Accessing these registers actually
accesses the associated FSR register pair, but also
performs a specific action on it stored value. They are:
• POSTDEC: accesses the FSR value, then
automatically decrements it by 1 afterwards
• POSTINC: accesses the FSR value, then
automatically increments it by 1 afterwards
• PREINC: increments the FSR value by 1, then
uses it in the operation
• PLUSW: adds the signed value of the W register
(range of -127 to 128) to that of the FSR and uses
the new value in the operation.
Indirect Addressing is accomplished with a set of
Indirect File Operands, INDF0 through INDF2. These
can be thought of as “virtual” registers; they are
mapped in the SFR space but are not physically implemented. Reading or writing to a particular INDF register
actually accesses its corresponding FSR register pair.
A read from INDF1, for example, reads the data at the
address indicated by FSR1H:FSR1L. Instructions that
use the INDF registers as operands actually use the
contents of their corresponding FSR as a pointer to the
instruction’s target. The INDF operand is just a
convenient way of using the pointer.
In this context, accessing an INDF register uses the
value in the FSR registers without changing them. Similarly, accessing a PLUSW register gives the FSR value
offset by that in the W register; neither value is actually
changed in the operation. Accessing the other virtual
registers changes the value of the FSR registers.
Because Indirect Addressing uses a full 12-bit address,
data RAM banking is not necessary. Thus, the current
contents of the BSR and the Access RAM bit have no
effect on determining the target address.
FIGURE 6-8:
FSR Registers and POSTINC,
POSTDEC, PREINC and PLUSW
Operations on the FSRs with POSTDEC, POSTINC
and PREINC affect the entire register pair; that is, rollovers of the FSRnL register, from FFh to 00h, carry
over to the FSRnH register. On the other hand, results
of these operations do not change the value of any
flags in the STATUS register (e.g., Z, N, OV, etc.).
INDIRECT ADDRESSING
000h
Using an instruction with one of the
Indirect Addressing registers as the
operand....
Bank 0
ADDWF, INDF1, 1
100h
Bank 1
200h
...uses the 12-bit address stored in
the FSR pair associated with that
register....
300h
FSR1H:FSR1L
7
0
x x x x 1 1 1 0
7
0
Bank 2
Bank 3
through
Bank 13
1 1 0 0 1 1 0 0
...to determine the data memory
location to be used in that operation.
In this case, the FSR1 pair contains
ECCh. This means the contents of
location ECCh will be added to that
of the W register and stored back in
ECCh.
E00h
Bank 14
F00h
FFFh
Bank 15
Data Memory
© 2009 Microchip Technology Inc.
DS39682E-page 67
PIC18F45J10 FAMILY
The PLUSW register can be used to implement a form
of Indexed Addressing in the data memory space. By
manipulating the value in the W register, users can
reach addresses that are fixed offsets from pointer
addresses. In some applications, this can be used to
implement some powerful program control structure,
such as software stacks, inside of data memory.
6.4.3.3
Operations by FSRs on FSRs
Indirect Addressing operations that target other FSRs
or virtual registers represent special cases. For
example, using an FSR to point to one of the virtual
registers will not result in successful operations. As a
specific case, assume that FSR0H:FSR0L contains
FE7h, the address of INDF1. Attempts to read the
value of the INDF1 using INDF0 as an operand will
return 00h. Attempts to write to INDF1 using INDF0 as
the operand will result in a NOP.
On the other hand, using the virtual registers to write to
an FSR pair may not occur as planned. In these cases,
the value will be written to the FSR pair but without any
incrementing or decrementing. Thus, writing to INDF2
or POSTDEC2 will write the same value to the
FSR2H:FSR2L.
Since the FSRs are physical registers mapped in the
SFR space, they can be manipulated through all direct
operations. Users should proceed cautiously when
working on these registers, particularly if their code
uses indirect addressing.
Similarly, operations by Indirect Addressing are generally permitted on all other SFRs. Users should exercise
the appropriate caution that they do not inadvertently
change settings that might affect the operation of the
device.
6.5
Data Memory and the Extended
Instruction Set
Enabling the PIC18 extended instruction set (XINST
Configuration bit = 1) significantly changes certain
aspects of data memory and its addressing. Specifically, the use of the Access Bank for many of the core
PIC18 instructions is different; this is due to the
introduction of a new addressing mode for the data
memory space.
What does not change is just as important. The size of
the data memory space is unchanged, as well as its
linear addressing. The SFR map remains the same.
Core PIC18 instructions can still operate in both Direct
and Indirect Addressing mode; inherent and literal
instructions do not change at all. Indirect addressing
with FSR0 and FSR1 also remains unchanged.
DS39682E-page 68
6.5.1
INDEXED ADDRESSING WITH
LITERAL OFFSET
Enabling the PIC18 extended instruction set changes
the behavior of Indirect Addressing using the FSR2
register pair within Access RAM. Under the proper
conditions, instructions that use the Access Bank – that
is, most bit-oriented and byte-oriented instructions –
can invoke a form of Indexed Addressing using an
offset specified in the instruction. This special addressing mode is known as Indexed Addressing with Literal
Offset, or Indexed Literal Offset mode.
When using the extended instruction set, this
addressing mode requires the following:
• The use of the Access Bank is forced (‘a’ = 0) and
• The file address argument is less than or equal to
5Fh.
Under these conditions, the file address of the instruction is not interpreted as the lower byte of an address
(used with the BSR in direct addressing), or as an 8-bit
address in the Access Bank. Instead, the value is
interpreted as an offset value to an Address Pointer,
specified by FSR2. The offset and the contents of
FSR2 are added to obtain the target address of the
operation.
6.5.2
INSTRUCTIONS AFFECTED BY
INDEXED LITERAL OFFSET MODE
Any of the core PIC18 instructions that can use Direct
Addressing are potentially affected by the Indexed
Literal Offset Addressing mode. This includes all
byte-oriented and bit-oriented instructions, or almost
one-half of the standard PIC18 instruction set.
Instructions that only use Inherent or Literal Addressing
modes are unaffected.
Additionally, byte-oriented and bit-oriented instructions
are not affected if they do not use the Access Bank
(Access RAM bit is ‘1’), or include a file address of 60h
or above. Instructions meeting these criteria will
continue to execute as before. A comparison of the
different possible addressing modes when the
extended instruction set is enabled in shown in
Figure 6-9.
Those who desire to use byte-oriented or bit-oriented
instructions in the Indexed Literal Offset mode should
note the changes to assembler syntax for this mode.
This is described in more detail in Section 22.2.1
“Extended Instruction Syntax”.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 6-9:
COMPARING ADDRESSING OPTIONS FOR BIT-ORIENTED AND
BYTE-ORIENTED INSTRUCTIONS (EXTENDED INSTRUCTION SET ENABLED)
Example Instruction: ADDWF, f, d, a (Opcode: 0010 01da ffff ffff)
When ‘a’ = 0 and f ≥ 60h:
The instruction executes in
Direct Forced mode. ‘f’ is interpreted as a location in the
Access RAM between 060h
and 0FFh. This is the same as
locations 060h to 07Fh
(Bank 0) and F80h to FFFh
(Bank 15) of data memory.
000h
Locations below 60h are not
available in this addressing
mode.
F00h
060h
080h
Bank 0
100h
00h
Bank 1
through
Bank 14
60h
80h
Access RAM
Valid Range
for ‘f’
FFh
Bank 15
F80h
SFRs
FFFh
Data Memory
When ‘a’ = 0 and f ≤ 5Fh:
The instruction executes in
Indexed Literal Offset mode. ‘f’
is interpreted as an offset to the
address value in FSR2. The
two are added together to
obtain the address of the target
register for the instruction. The
address can be anywhere in
the data memory space.
Note that in this mode, the
correct syntax is now:
ADDWF [k], d
where ‘k’ is the same as ‘f’.
000h
Bank 0
080h
100h
001001da ffffffff
Bank 1
through
Bank 14
FSR2H
FSR2L
F00h
Bank 15
F80h
SFRs
FFFh
Data Memory
When ‘a’ = 1 (all values of f):
The instruction executes in
Direct mode (also known as
Direct Long mode). ‘f’ is interpreted as a location in one of
the 16 banks of the data
memory space. The bank is
designated by the Bank Select
Register (BSR). The address
can be in any implemented
bank in the data memory
space.
BSR
00000000
000h
Bank 0
080h
100h
Bank 1
through
Bank 14
001001da ffffffff
F00h
Bank 15
F80h
SFRs
FFFh
Data Memory
© 2009 Microchip Technology Inc.
DS39682E-page 69
PIC18F45J10 FAMILY
6.5.3
MAPPING THE ACCESS BANK IN
INDEXED LITERAL OFFSET MODE
The use of Indexed Literal Offset Addressing mode
effectively changes how the first 96 locations of Access
RAM (00h to 5Fh) are mapped. Rather than containing
just the contents of the bottom half of Bank 0, this mode
maps the contents from Bank 0 and a user-defined
“window” that can be located anywhere in the data
memory space. The value of FSR2 establishes the
lower boundary of the addresses mapped into the
window, while the upper boundary is defined by FSR2
plus 95 (5Fh). Addresses in the Access RAM above
5Fh are mapped as previously described (see
Section 6.3.2 “Access Bank”). An example of Access
Bank remapping in this addressing mode is shown in
Figure 6-10.
FIGURE 6-10:
Remapping of the Access Bank applies only to operations using the Indexed Literal Offset mode. Operations
that use the BSR (Access RAM bit is ‘1’) will continue
to use Direct Addressing as before.
6.6
PIC18 Instruction Execution and
the Extended Instruction Set
Enabling the extended instruction set adds eight
additional commands to the existing PIC18 instruction
set. These instructions are executed as described in
Section 22.2 “Extended Instruction Set”.
REMAPPING THE ACCESS BANK WITH INDEXED LITERAL OFFSET
ADDRESSING
Example Situation:
ADDWF f, d, a
FSR2H:FSR2L = 120h
Locations in the region
from the FSR2 Pointer
(120h) to the pointer plus
05Fh (17Fh) are mapped
to the bottom of the
Access RAM (000h-05Fh).
000h
05Fh
07Fh
Bank 0
100h
120h
17Fh
200h
Bank 0 addresses below
5Fh can still be addressed
by using the BSR.
Bank 1
Window
Bank 1
00h
Bank 1 “Window”
5Fh
Locations in Bank 0 from
060h to 07Fh are mapped,
as usual, to the middle half
of the Access Bank.
Special Function Registers
at F80h through FFFh are
mapped to 80h through
FFh, as usual.
Bank 0
Bank 0
Bank 2
through
Bank 14
7Fh
80h
SFRs
FFh
Access Bank
F00h
Bank 15
F80h
FFFh
SFRs
Data Memory
DS39682E-page 70
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
7.0
FLASH PROGRAM MEMORY
7.1
Table Reads and Table Writes
The Flash program memory is readable, writable and
erasable during normal operation over the entire VDD
range.
In order to read and write program memory, there are
two operations that allow the processor to move bytes
between the program memory space and the data RAM:
A read from program memory is executed on one byte
at a time. A write to program memory is executed on
blocks of 64 bytes at a time. Program memory is
erased in blocks of 1024 bytes at a time. A Bulk Erase
operation may not be issued from user code.
• Table Read (TBLRD)
• Table Write (TBLWT)
Writing or erasing program memory will cease
instruction fetches until the operation is complete. The
program memory cannot be accessed during the write
or erase; therefore, code cannot execute. An internal
programming timer terminates program memory writes
and erases.
A value written to program memory does not need to be
a valid instruction. Executing a program memory
location that forms an invalid instruction results in a
NOP.
The program memory space is 16 bits wide, while the
data RAM space is 8 bits wide. Table reads and table
writes move data between these two memory spaces
through an 8-bit register (TABLAT).
Table read operations retrieve data from program
memory and place it into the data RAM space.
Figure 7-1 shows the operation of a table read with
program memory and data RAM.
Table write operations store data from the data memory
space into holding registers in program memory. The
procedure to write the contents of the holding registers
into program memory is detailed in Section 7.5 “Writing
to Flash Program Memory”. Figure 7-2 shows the
operation of a table write with program memory and data
RAM.
Table operations work with byte entities. A table block
containing data, rather than program instructions, is not
required to be word aligned. Therefore, a table block can
start and end at any byte address. If a table write is being
used to write executable code into program memory,
program instructions will need to be word-aligned.
FIGURE 7-1:
TABLE READ OPERATION
Instruction: TBLRD*
Program Memory
Table Pointer(1)
TBLPTRU
TBLPTRH
Table Latch (8-bit)
TBLPTRL
TABLAT
Program Memory
(TBLPTR)
Note 1: Table Pointer register points to a byte in program memory.
© 2009 Microchip Technology Inc.
DS39682E-page 71
PIC18F45J10 FAMILY
FIGURE 7-2:
TABLE WRITE OPERATION
Instruction: TBLWT*
Program Memory
Holding Registers
Table Pointer(1)
TBLPTRU
TBLPTRH
Table Latch (8-bit)
TBLPTRL
TABLAT
Program Memory
(TBLPTR)
Note 1: Table Pointer actually points to one of 64 holding registers, the address of which is determined by
TBLPTRL<5:0>. The process for physically writing data to the program memory array is discussed in
Section 7.5 “Writing to Flash Program Memory”.
7.2
Control Registers
Several control registers are used in conjunction with
the TBLRD and TBLWT instructions. These include the:
•
•
•
•
EECON1 register
EECON2 register
TABLAT register
TBLPTR registers
7.2.1
EECON1 AND EECON2 REGISTERS
The EECON1 register (Register 7-1) is the control
register for memory accesses. The EECON2 register is
not a physical register; it is used exclusively in the
memory write and erase sequences. Reading
EECON2 will read all ‘0’s.
The WREN bit, when set, will allow a write operation.
On power-up, the WREN bit is clear. The WRERR bit is
set in hardware when the WR bit is set and cleared
when the internal programming timer expires and the
write operation is complete.
Note:
During normal operation, the WRERR is
read as ‘1’. This can indicate that a write
operation was prematurely terminated by
a Reset, or a write operation was
attempted improperly.
The WR control bit initiates write operations. The bit
cannot be cleared, only set, in software; it is cleared in
hardware at the completion of the write operation.
The FREE bit, when set, will allow a program memory
erase operation. When FREE is set, the erase
operation is initiated on the next WR command. When
FREE is clear, only writes are enabled.
DS39682E-page 72
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 7-1:
EECON1: EEPROM CONTROL REGISTER 1
U-0
U-0
U-0
R/W-0
R/W-x
R/W-0
R/S-0
U-0
—
—
—
FREE
WRERR
WREN
WR
—
bit 7
bit 0
Legend:
U = Unimplemented bit, read as ‘0’
R = Readable bit
W = Writable bit
S = Settable bit (cannot be cleared in software)
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-5
Unimplemented: Read as ‘0’
bit 4
FREE: Flash Row Erase Enable bit
1 = Performs an erase operation on the next WR command (cleared by completion of erase operation)
0 = Perform write only
bit 3
WRERR: Flash Program Error Flag bit
1 = A write operation is prematurely terminated (any Reset during self-timed programming in normal
operation, or an improper write attempt)
0 = The write operation completed
bit 2
WREN: Flash Program Write Enable bit
1 = Allows write cycles to Flash program
0 = Inhibits write cycles to Flash program
bit 1
WR: Write Control bit
1 = Initiates a program memory erase cycle or write cycle.
(The operation is self-timed and the bit is cleared by hardware once write is complete. The WR bit
can only be set (not cleared) in software.)
0 = Write cycle is complete
bit 0
Unimplemented: Read as ‘0’
© 2009 Microchip Technology Inc.
DS39682E-page 73
PIC18F45J10 FAMILY
7.2.2
TABLAT – TABLE LATCH REGISTER
7.2.4
The Table Latch (TABLAT) is an 8-bit register mapped
into the SFR space. The Table Latch register is used to
hold 8-bit data during data transfers between program
memory and data RAM.
7.2.3
TBLPTR is used in reads, writes and erases of the
Flash program memory.
When a TBLRD is executed, all 22 bits of the TBLPTR
determine which byte is read from program memory
into TABLAT.
TBLPTR – TABLE POINTER
REGISTER
When a TBLWT is executed, the six LSbs of the Table
Pointer register (TBLPTR<5:0>) determine which of
the 64 program memory holding registers is written to.
When the timed write to program memory begins (via
the WR bit), the 16 MSbs of the TBLPTR
(TBLPTR<20:6>) determine which program memory
block of 64 bytes is written to. For more detail, see
Section 7.5 “Writing to Flash Program Memory”.
The Table Pointer (TBLPTR) register addresses a byte
within the program memory. The TBLPTR is comprised
of three SFR registers: Table Pointer Upper Byte, Table
Pointer High Byte and Table Pointer Low Byte
(TBLPTRU:TBLPTRH:TBLPTRL). These three registers join to form a 22-bit wide pointer. The low-order
21 bits allow the device to address up to 2 Mbytes of
program memory space. The 22nd bit allows access to
the device ID, the user ID and the Configuration bits.
When an erase of program memory is executed, the
7 MSbs of the Table Pointer register (TBLPTR<20:10>)
point to the 1024-byte block that will be erased. The
Least Significant bits (TBLPTR<9:0>) are ignored.
The Table Pointer register, TBLPTR, is used by the
TBLRD and TBLWT instructions. These instructions can
update the TBLPTR in one of four ways based on the
table operation. These operations are shown in
Table 7-1. These operations on the TBLPTR only affect
the low-order 21 bits.
TABLE 7-1:
TABLE POINTER BOUNDARIES
Figure 7-3 describes the relevant boundaries of
TBLPTR based on Flash program memory operations.
TABLE POINTER OPERATIONS WITH TBLRD AND TBLWT INSTRUCTIONS
Example
Operation on Table Pointer
TBLRD*
TBLWT*
TBLPTR is not modified
TBLRD*+
TBLWT*+
TBLPTR is incremented after the read/write
TBLRD*TBLWT*-
TBLPTR is decremented after the read/write
TBLRD+*
TBLWT+*
TBLPTR is incremented before the read/write
FIGURE 7-3:
21
TABLE POINTER BOUNDARIES BASED ON OPERATION
TBLPTRU
16
15
TBLPTRH
8
7
TBLPTRL
0
Table Erase
TBLPTR<20:10>
Table Write
TBLPTR<20:6>
Table Write
TBLPTR<5:0>
Table Read – TBLPTR<21:0>
DS39682E-page 74
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
7.3
TBLPTR points to a byte address in program space.
Executing TBLRD places the byte pointed to into
TABLAT. In addition, TBLPTR can be modified
automatically for the next table read operation.
Reading the Flash Program
Memory
The TBLRD instruction is used to retrieve data from
program memory and places it into data RAM. Table
reads from program memory are performed one byte at
a time.
FIGURE 7-4:
The internal program memory is typically organized by
words. The Least Significant bit of the address selects
between the high and low bytes of the word. Figure 7-4
shows the interface between the internal program
memory and the TABLAT.
READS FROM FLASH PROGRAM MEMORY
Program Memory
(Even Byte Address)
(Odd Byte Address)
TBLPTR = xxxxx1
Instruction Register
(IR)
EXAMPLE 7-1:
FETCH
TBLRD
TBLPTR = xxxxx0
TABLAT
Read Register
READING A FLASH PROGRAM MEMORY WORD
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
; Load TBLPTR with the base
; address of the word
READ_WORD
TBLRD*+
MOVF
MOVWF
TBLRD*+
MOVF
MOVWF
TABLAT, W
WORD_EVEN
TABLAT, W
WORD_ODD
© 2009 Microchip Technology Inc.
; read into TABLAT and increment
; get data
; read into TABLAT and increment
; get data
DS39682E-page 75
PIC18F45J10 FAMILY
7.4
Erasing Flash Program Memory
The minimum erase block is 1024 bytes. Only through
the use of an external programmer, or through ICSP
control, can larger blocks of program memory be Bulk
Erased. Word Erase in the Flash array is not supported.
When initiating an erase sequence from the microcontroller itself, a block of 1024 bytes of program
memory is erased. The Most Significant 7 bits of the
TBLPTR<21:10> point to the block being erased.
TBLPTR<9:0> are ignored.
The EECON1 register commands the erase operation.
The WREN bit must be set to enable write operations.
The FREE bit is set to select an erase operation.
For protection, the write initiate sequence for EECON2
must be used.
7.4.1
FLASH PROGRAM MEMORY
ERASE SEQUENCE
The sequence of events for erasing a block of internal
program memory location is:
1.
2.
3.
4.
5.
6.
7.
8.
Load Table Pointer register with address of the
block being erased.
Set the WREN and FREE bits (EECON1<2,4>)
to enable the erase operation.
Disable interrupts.
Write 55h to EECON2.
Write 0AAh to EECON2.
Set the WR bit. This will begin the erase cycle.
The CPU will stall for duration of the erase for
TIE (see parameter D133B).
Re-enable interrupts.
A long write is necessary for erasing the internal Flash.
Instruction execution is halted while in a long write
cycle. The long write will be terminated by the internal
programming timer.
EXAMPLE 7-2:
ERASING A FLASH PROGRAM MEMORY BLOCK
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
; load TBLPTR with the base
; address of the memory block
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
EECON1,
EECON1,
INTCON,
55h
EECON2
0AAh
EECON2
EECON1,
INTCON,
; enable write to memory
; enable Erase operation
; disable interrupts
ERASE_ROW
Required
Sequence
DS39682E-page 76
WREN
FREE
GIE
; write 55h
WR
GIE
; write 0AAh
; start erase (CPU stall)
; re-enable interrupts
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
7.5
Writing to Flash Program Memory
The minimum programming block is 32 words or
64 bytes. Word or byte programming is not supported.
The EEPROM on-chip timer controls the write time.
The write/erase voltages are generated by an on-chip
charge pump, rated to operate over the voltage range
of the device.
Table writes are used internally to load the holding
registers needed to program the Flash memory. There
are 64 holding registers used by the table writes for
programming.
Note:
Since the Table Latch (TABLAT) is only a single byte, the
TBLWT instruction may need to be executed 64 times for
each programming operation. All of the table write
operations will essentially be short writes because only
the holding registers are written. At the end of updating
the 64 holding registers, the EECON1 register must be
written to in order to start the programming operation
with a long write.
In order to maintain the endurance of the
cells, each Flash byte should not be
programmed more then twice between
erase operations. Either a Bulk or Row
Erase of the target row is required before
attempting to modify the contents a third
time.
The long write is necessary for programming the internal Flash. Instruction execution is halted while in a long
write cycle. The long write will be terminated by the
internal programming timer.
FIGURE 7-5:
Unlike previous devices, the PIC18F45J10
family of devices does not reset the holding
registers after a write occurs. The holding
registers must be cleared or overwritten
before a programming sequence.
TABLE WRITES TO FLASH PROGRAM MEMORY
TABLAT
Write Register
8
8
TBLPTR = xxxxx0
TBLPTR = xxxxx1
Holding Register
8
TBLPTR = xxxx3F
TBLPTR = xxxxx2
Holding Register
8
Holding Register
Holding Register
Program Memory
7.5.1
FLASH PROGRAM MEMORY WRITE
SEQUENCE
The sequence of events for programming an internal
program memory location should be:
1.
2.
3.
4.
If the section of program memory to be written to
has been programmed previously, then the
memory will need to be erased before the write
occurs (see Section 7.4.1 “Flash Program
Memory Erase Sequence”).
Write the 64 bytes into the holding registers with
auto-increment.
Set the EECON1 register for the write operation:
• set WREN to enable byte writes.
Disable interrupts.
© 2009 Microchip Technology Inc.
5.
6.
7.
8.
Write 55h to EECON2.
Write 0AAh to EECON2.
Set the WR bit. This will begin the write cycle.
The CPU will stall for duration of the write (about
2 ms using internal timer).
9. Re-enable interrupts.
10. Verify the memory (table read).
An example of the required code is shown in
Example 7-3.
Note:
Before setting the WR bit, the Table
Pointer address needs to be within the
intended address range of the 64 bytes in
the holding register.
DS39682E-page 77
PIC18F45J10 FAMILY
EXAMPLE 7-3:
WRITING TO FLASH PROGRAM MEMORY
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
; Load TBLPTR with the base
; address of the memory block
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
MOVLW
MOVWF
EECON1, WREN
EECON1, FREE
INTCON, GIE
55h
EECON2
0AAh
EECON2
EECON1, WR
INTCON, GIE
D'16'
WRITE_COUNTER
; enable write to memory
; enable Erase operation
; disable interrupts
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
D'64'
COUNTER
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
ERASE_BLOCK
; write 55h
; write 0AAh
; start erase (CPU stall)
; re-enable interrupts
; Need to write 16 blocks of 64 to write
; one erase block of 1024
RESTART_BUFFER
; point to buffer
FILL_BUFFER
...
; read the new data from I2C, SPI,
; PSP, USART, etc.
WRITE_BUFFER
MOVLW
MOVWF
WRITE_BYTE_TO_HREGS
MOVFF
MOVWF
TBLWT+*
D’64'
COUNTER
; number of bytes in holding register
POSTINC0, WREG
TABLAT
;
;
;
;
;
DECFSZ COUNTER
BRA
WRITE_BYTE_TO_HREGS
get low byte of buffer data
present data to table latch
write data, perform a short write
to internal TBLWT holding register.
loop until buffers are full
PROGRAM_MEMORY
Required
Sequence
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
BCF
EECON1,
INTCON,
55h
EECON2
0AAh
EECON2
EECON1,
INTCON,
EECON1,
WREN
GIE
; write 55h
WR
GIE
WREN
DECFSZ WRITE_COUNTER
BRA
RESTART_BUFFER
DS39682E-page 78
; enable write to memory
; disable interrupts
;
;
;
;
write 0AAh
start program (CPU stall)
re-enable interrupts
disable write to memory
; done with one write cycle
; if not done replacing the erase block
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
7.5.2
WRITE VERIFY
7.5.4
Depending on the application, good programming
practice may dictate that the value written to the
memory should be verified against the original value.
This should be used in applications where excessive
writes can stress bits near the specification limit.
7.5.3
UNEXPECTED TERMINATION OF
WRITE OPERATION
If a write is terminated by an unplanned event, such as
loss of power or an unexpected Reset, the memory
location just programmed should be verified and reprogrammed if needed. If the write operation is interrupted
by a MCLR Reset or a WDT Time-out Reset during
normal operation, the user can check the WRERR bit
and rewrite the location(s) as needed.
TABLE 7-2:
PROTECTION AGAINST
SPURIOUS WRITES
To protect against spurious writes to Flash program
memory, the write initiate sequence must also be
followed. See Section 21.0 “Special Features of the
CPU” for more detail.
7.6
Flash Program Operation During
Code Protection
See Section 21.6 “Program Verification and Code
Protection” for details on code protection of Flash
program memory.
REGISTERS ASSOCIATED WITH PROGRAM FLASH MEMORY
Name
Bit 7
Bit 6
Bit 5
TBLPTRU
—
—
bit 21
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Program Memory Table Pointer Upper Byte (TBLPTR<20:16>)
Reset
Values on
page
47
TBPLTRH Program Memory Table Pointer High Byte (TBLPTR<15:8>)
47
TBLPTRL Program Memory Table Pointer Low Byte (TBLPTR<7:0>)
47
TABLAT
Program Memory Table Latch
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
47
EECON2
EEPROM Control Register 2 (not a physical register)
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
49
—
—
—
FREE
WRERR
WREN
WR
—
49
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
49
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
EECON1
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during Flash/EEPROM access.
© 2009 Microchip Technology Inc.
DS39682E-page 79
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 80
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
8.0
8 x 8 HARDWARE MULTIPLIER
8.1
Introduction
EXAMPLE 8-1:
MOVF
MULWF
All PIC18 devices include an 8 x 8 hardware multiplier
as part of the ALU. The multiplier performs an unsigned
operation and yields a 16-bit result that is stored in the
product register pair, PRODH:PRODL. The multiplier’s
operation does not affect any flags in the STATUS
register.
ARG1, W
ARG2
EXAMPLE 8-2:
Making multiplication a hardware operation allows it to
be completed in a single instruction cycle. This has the
advantages of higher computational throughput and
reduced code size for multiplication algorithms and
allows the PIC18 devices to be used in many applications previously reserved for digital signal processors.
A comparison of various hardware and software
multiply operations, along with the savings in memory
and execution time, is shown in Table 8-1.
8.2
8 x 8 UNSIGNED
MULTIPLY ROUTINE
;
; ARG1 * ARG2 ->
; PRODH:PRODL
8 x 8 SIGNED MULTIPLY
ROUTINE
MOVF
MULWF
ARG1, W
ARG2
BTFSC
SUBWF
ARG2, SB
PRODH, F
MOVF
BTFSC
SUBWF
ARG2, W
ARG1, SB
PRODH, F
;
;
;
;
;
ARG1 * ARG2 ->
PRODH:PRODL
Test Sign Bit
PRODH = PRODH
- ARG1
; Test Sign Bit
; PRODH = PRODH
;
- ARG2
Operation
Example 8-1 shows the instruction sequence for an 8 x 8
unsigned multiplication. Only one instruction is required
when one of the arguments is already loaded in the
WREG register.
Example 8-2 shows the sequence to do an 8 x 8 signed
multiplication. To account for the sign bits of the
arguments, each argument’s Most Significant bit (MSb)
is tested and the appropriate subtractions are done.
TABLE 8-1:
PERFORMANCE COMPARISON FOR VARIOUS MULTIPLY OPERATIONS
Routine
8 x 8 unsigned
8 x 8 signed
16 x 16 unsigned
16 x 16 signed
Multiply Method
Without hardware multiply
Program
Memory
(Words)
Cycles
(Max)
@ 40 MHz
@ 10 MHz
@ 4 MHz
13
69
6.9 μs
27.6 μs
69 μs
Time
Hardware multiply
1
1
100 ns
400 ns
1 μs
Without hardware multiply
33
91
9.1 μs
36.4 μs
91 μs
Hardware multiply
6
6
600 ns
2.4 μs
6 μs
Without hardware multiply
21
242
24.2 μs
96.8 μs
242 μs
Hardware multiply
28
28
2.8 μs
11.2 μs
28 μs
Without hardware multiply
52
254
25.4 μs
102.6 μs
254 μs
Hardware multiply
35
40
4.0 μs
16.0 μs
40 μs
© 2009 Microchip Technology Inc.
DS39682E-page 81
PIC18F45J10 FAMILY
Example 8-3 shows the sequence to do a 16 x 16
unsigned multiplication. Equation 8-1 shows the
algorithm that is used. The 32-bit result is stored in four
registers (RES3:RES0).
EQUATION 8-1:
RES3:RES0
=
=
EXAMPLE 8-3:
16 x 16 UNSIGNED
MULTIPLICATION
ALGORITHM
ARG1H:ARG1L • ARG2H:ARG2L
(ARG1H • ARG2H • 216) +
(ARG1H • ARG2L • 28) +
(ARG1L • ARG2H • 28) +
(ARG1L • ARG2L)
EQUATION 8-2:
RES3:RES0 = ARG1H:ARG1L • ARG2H:ARG2L
= (ARG1H • ARG2H • 216) +
(ARG1H • ARG2L • 28) +
(ARG1L • ARG2H • 28) +
(ARG1L • ARG2L) +
(-1 • ARG2H<7> • ARG1H:ARG1L • 216) +
(-1 • ARG1H<7> • ARG2H:ARG2L • 216)
EXAMPLE 8-4:
16 x 16 UNSIGNED
MULTIPLY ROUTINE
MOVF
MULWF
ARG1L, W
ARG2L
MOVFF
MOVFF
PRODH, RES1
PRODL, RES0
MOVF
MULWF
ARG1H, W
ARG2H
MOVFF
MOVFF
PRODH, RES3
PRODL, RES2
MOVF
MULWF
ARG1L, W
ARG2H
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1, F
PRODH, W
RES2, F
WREG
RES3, F
MOVF
MULWF
ARG1H, W
ARG2L
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1, F
PRODH, W
RES2, F
WREG
RES3, F
; ARG1L * ARG2L->
; PRODH:PRODL
;
;
ARG1L * ARG2H->
PRODH:PRODL
Add cross
products
ARG1H * ARG2L->
PRODH:PRODL
Add cross
products
Example 8-4 shows the sequence to do a 16 x 16
signed multiply. Equation 8-2 shows the algorithm
used. The 32-bit result is stored in four registers
(RES3:RES0). To account for the sign bits of the
arguments, the MSb for each argument pair is tested
and the appropriate subtractions are done.
DS39682E-page 82
ARG1L, W
ARG2L
MOVFF
MOVFF
PRODH, RES1
PRODL, RES0
MOVF
MULWF
ARG1H, W
ARG2H
MOVFF
MOVFF
PRODH, RES3
PRODL, RES2
MOVF
MULWF
ARG1L, W
ARG2H
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1, F
PRODH, W
RES2, F
WREG
RES3, F
MOVF
MULWF
ARG1H, W
ARG2L
MOVF
ADDWF
MOVF
ADDWFC
CLRF
ADDWFC
PRODL, W
RES1, F
PRODH, W
RES2, F
WREG
RES3, F
BTFSS
BRA
MOVF
SUBWF
MOVF
SUBWFB
ARG2H, 7
SIGN_ARG1
ARG1L, W
RES2
ARG1H, W
RES3
; ARG2H:ARG2L neg?
; no, check ARG1
;
;
;
ARG1H, 7
CONT_CODE
ARG2L, W
RES2
ARG2H, W
RES3
; ARG1H:ARG1L neg?
; no, done
;
;
;
; ARG1L * ARG2L ->
; PRODH:PRODL
;
;
; ARG1H * ARG2H ->
; PRODH:PRODL
;
;
;
;
;
;
;
;
;
;
ARG1L * ARG2H ->
PRODH:PRODL
Add cross
products
;
;
;
;
;
;
;
;
;
;
;
MOVF
MULWF
;
;
;
;
;
;
;
;
;
;
16 x 16 SIGNED
MULTIPLY ROUTINE
;
;
; ARG1H * ARG2H->
; PRODH:PRODL
;
;
16 x 16 SIGNED
MULTIPLICATION
ALGORITHM
;
;
;
;
;
;
;
;
;
ARG1H * ARG2L ->
PRODH:PRODL
Add cross
products
;
;
SIGN_ARG1
BTFSS
BRA
MOVF
SUBWF
MOVF
SUBWFB
;
CONT_CODE
:
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
9.0
INTERRUPTS
Members of the PIC18F45J10 family of devices have
multiple interrupt sources and an interrupt priority
feature that allows most interrupt sources to be
assigned a high-priority level or a low-priority level. The
high-priority interrupt vector is at 0008h and the
low-priority interrupt vector is at 0018h. High-priority
interrupt events will interrupt any low-priority interrupts
that may be in progress.
There are thirteen registers which are used to control
interrupt operation. These registers are:
•
•
•
•
•
•
•
RCON
INTCON
INTCON2
INTCON3
PIR1, PIR2, PIR3
PIE1, PIE2, PIE3
IPR1, IPR2, IPR3
It is recommended that the Microchip header files
supplied with MPLAB® IDE be used for the symbolic bit
names in these registers. This allows the
assembler/compiler to automatically take care of the
placement of these bits within the specified register.
In general, interrupt sources have three bits to control
their operation. They are:
• Flag bit to indicate that an interrupt event
occurred
• Enable bit that allows program execution to
branch to the interrupt vector address when the
flag bit is set
• Priority bit to select high priority or low priority
The interrupt priority feature is enabled by setting the
IPEN bit (RCON<7>). When interrupt priority is
enabled, there are two bits which enable interrupts
globally. Setting the GIEH bit (INTCON<7>) enables all
interrupts that have the priority bit set (high priority).
Setting the GIEL bit (INTCON<6>) enables all
interrupts that have the priority bit cleared (low priority).
When the interrupt flag, enable bit and appropriate
global interrupt enable bit are set, the interrupt will
vector immediately to address 0008h or 0018h,
depending on the priority bit setting. Individual
interrupts can be disabled through their corresponding
enable bits.
© 2009 Microchip Technology Inc.
When the IPEN bit is cleared (default state), the
interrupt priority feature is disabled and interrupts are
compatible with PIC® mid-range devices. In
Compatibility mode, the interrupt priority bits for each
source have no effect. INTCON<6> is the PEIE bit
which enables/disables all peripheral interrupt sources.
INTCON<7> is the GIE bit which enables/disables all
interrupt sources. All interrupts branch to address
0008h in Compatibility mode.
When an interrupt is responded to, the global interrupt
enable bit is cleared to disable further interrupts. If the
IPEN bit is cleared, this is the GIE bit. If interrupt priority
levels are used, this will be either the GIEH or GIEL bit.
High-priority interrupt sources can interrupt a
low-priority interrupt. Low-priority interrupts are not
processed while high-priority interrupts are in progress.
The return address is pushed onto the stack and the
PC is loaded with the interrupt vector address (0008h
or 0018h). Once in the Interrupt Service Routine, the
source(s) of the interrupt can be determined by polling
the interrupt flag bits. The interrupt flag bits must be
cleared in software before re-enabling interrupts to
avoid recursive interrupts.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine and sets the GIE bit (GIEH or GIEL
if priority levels are used) which re-enables interrupts.
For external interrupt events, such as the INTx pins or
the PORTB input change interrupt, the interrupt latency
will be three to four instruction cycles. The exact
latency is the same for one or two-cycle instructions.
Individual interrupt flag bits are set regardless of the
status of their corresponding enable bit or the GIE bit.
Note:
Do not use the MOVFF instruction to modify
any of the interrupt control registers while
any interrupt is enabled. Doing so may
cause erratic microcontroller behavior.
DS39682E-page 83
PIC18F45J10 FAMILY
FIGURE 9-1:
PIC18F24J10/25J10/44J10/45J10 INTERRUPT LOGIC
Wake-up if in
Idle or Sleep modes
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
INT0IF
INT0IE
INT1IF
INT1IE
INT1IP
INT2IF
INT2IE
INT2IP
PIR1<7:0>
PIE1<7:0>
IPR1<7:0>
PIR2<7:6, 3, 0>
PIE2<7:6, 3, 0>
IPR2<7:6, 3, 0>
Interrupt to CPU
Vector to Location
0008h
GIE/GIEH
IPEN
PIR3<7:6>
PIE3<7:6>
IPR3<7:6>
IPEN
PEIE/GIEL
IPEN
High-Priority Interrupt Generation
Low-Priority Interrupt Generation
PIR1<7:0>
PIE1<7:0>
IPR1<7:0>
PIR2<7:6, 3, 0>
PIE2<7:6, 3, 0>
IPR2<7:6, 3, 0>
PIR3<7:6>
PIE3<7:6>
IPR3<7:6>
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
INT1IF
INT1IE
INT1IP
Interrupt to CPU
Vector to Location
0018h
IPEN
GIE/GIEH
PEIE/GIEL
INT2IF
INT2IE
INT2IP
DS39682E-page 84
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
9.1
INTCON Registers
Note:
The INTCON registers are readable and writable
registers which contain various enable, priority and flag
bits.
REGISTER 9-1:
Interrupt flag bits are set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the global
interrupt enable bit. User software should
ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt.
This feature allows for software polling.
INTCON: INTERRUPT CONTROL REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-x
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
GIE/GIEH: Global Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked interrupts
0 = Disables all interrupts
When IPEN = 1:
1 = Enables all high-priority interrupts
0 = Disables all interrupts
bit 6
PEIE/GIEL: Peripheral Interrupt Enable bit
When IPEN = 0:
1 = Enables all unmasked peripheral interrupts
0 = Disables all peripheral interrupts
When IPEN = 1:
1 = Enables all low-priority peripheral interrupts
0 = Disables all low-priority peripheral interrupts
bit 5
TMR0IE: TMR0 Overflow Interrupt Enable bit
1 = Enables the TMR0 overflow interrupt
0 = Disables the TMR0 overflow interrupt
bit 4
INT0IE: INT0 External Interrupt Enable bit
1 = Enables the INT0 external interrupt
0 = Disables the INT0 external interrupt
bit 3
RBIE: RB Port Change Interrupt Enable bit
1 = Enables the RB port change interrupt
0 = Disables the RB port change interrupt
bit 2
TMR0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (must be cleared in software)
0 = TMR0 register did not overflow
bit 1
INT0IF: INT0 External Interrupt Flag bit
1 = The INT0 external interrupt occurred (must be cleared in software)
0 = The INT0 external interrupt did not occur
bit 0
RBIF: RB Port Change Interrupt Flag bit(1)
1 = At least one of the RB<7:4> pins changed state (must be cleared in software)
0 = None of the RB<7:4> pins have changed state
Note 1:
A mismatch condition will continue to set this bit. Reading PORTB will end the mismatch condition and
allow the bit to be cleared.
© 2009 Microchip Technology Inc.
DS39682E-page 85
PIC18F45J10 FAMILY
REGISTER 9-2:
INTCON2: INTERRUPT CONTROL REGISTER 2
R/W-1
R/W-1
R/W-1
R/W-1
U-0
R/W-1
U-0
R/W-1
RBPU
INTEDG0
INTEDG1
INTEDG2
—
TMR0IP
—
RBIP
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
RBPU: PORTB Pull-up Enable bit
1 = All PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual port latch values
bit 6
INTEDG0: External Interrupt 0 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 5
INTEDG1: External Interrupt 1 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 4
INTEDG2: External Interrupt 2 Edge Select bit
1 = Interrupt on rising edge
0 = Interrupt on falling edge
bit 3
Unimplemented: Read as ‘0’
bit 2
TMR0IP: TMR0 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
Unimplemented: Read as ‘0’
bit 0
RBIP: RB Port Change Interrupt Priority bit
1 = High priority
0 = Low priority
Note:
x = Bit is unknown
Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding
enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt. This feature allows for software polling.
DS39682E-page 86
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 9-3:
INTCON3: INTERRUPT CONTROL REGISTER 3
R/W-1
R/W-1
U-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
INT2IP: INT2 External Interrupt Priority bit
1 = High priority
0 = Low priority
bit 6
INT1IP: INT1 External Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
Unimplemented: Read as ‘0’
bit 4
INT2IE: INT2 External Interrupt Enable bit
1 = Enables the INT2 external interrupt
0 = Disables the INT2 external interrupt
bit 3
INT1IE: INT1 External Interrupt Enable bit
1 = Enables the INT1 external interrupt
0 = Disables the INT1 external interrupt
bit 2
Unimplemented: Read as ‘0’
bit 1
INT2IF: INT2 External Interrupt Flag bit
1 = The INT2 external interrupt occurred (must be cleared in software)
0 = The INT2 external interrupt did not occur
bit 0
INT1IF: INT1 External Interrupt Flag bit
1 = The INT1 external interrupt occurred (must be cleared in software)
0 = The INT1 external interrupt did not occur
Note:
x = Bit is unknown
Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding
enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits
are clear prior to enabling an interrupt. This feature allows for software polling.
© 2009 Microchip Technology Inc.
DS39682E-page 87
PIC18F45J10 FAMILY
9.2
PIR Registers
The PIR registers contain the individual flag bits for the
peripheral interrupts. Due to the number of peripheral
interrupt sources, there are three Peripheral Interrupt
Request (Flag) registers (PIR1, PIR2, PIR3).
REGISTER 9-4:
Note 1: Interrupt flag bits are set when an interrupt
condition occurs regardless of the state of
its corresponding enable bit or the Global
Interrupt Enable bit, GIE (INTCON<7>).
2: User software should ensure the
appropriate interrupt flag bits are cleared
prior to enabling an interrupt and after
servicing that interrupt.
PIR1: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 1
R/W-0
R/W-0
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
PSPIF: Parallel Slave Port Read/Write Interrupt Flag bit(1)
1 = A read or a write operation has taken place (must be cleared in software)
0 = No read or write has occurred
bit 6
ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared in software)
0 = The A/D conversion is not complete
bit 5
RCIF: EUSART Receive Interrupt Flag bit
1 = The EUSART receive buffer, RCREG, is full (cleared when RCREG is read)
0 = The EUSART receive buffer is empty
bit 4
TXIF: EUSART Transmit Interrupt Flag bit
1 = The EUSART transmit buffer, TXREG, is empty (cleared when TXREG is written)
0 = The EUSART transmit buffer is full
bit 3
SSP1IF: Master Synchronous Serial Port 1 Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
bit 2
CCP1IF: ECCP1/CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode.
bit 1
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
bit 0
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
Note 1:
This bit is not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 88
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 9-5:
PIR2: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 2
R/W-0
R/W-0
U-0
U-0
R/W-0
U-0
U-0
R/W-0
OSCFIF
CMIF
—
—
BCLIF
—
—
CCP2IF
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
OSCFIF: Oscillator Fail Interrupt Flag bit
1 = Device oscillator failed, clock input has changed to INTOSC (must be cleared in software)
0 = Device clock operating
bit 6
CMIF: Comparator Interrupt Flag bit
1 = Comparator input has changed (must be cleared in software)
0 = Comparator input has not changed
bit 5-4
Unimplemented: Read as ‘0’
bit 3
BCLIF: Bus Collision Interrupt Flag bit (MSSP1 module)
1 = A bus collision occurred (must be cleared in software)
0 = No bus collision occurred
bit 2-1
Unimplemented: Read as ‘0’
bit 0
CCP2IF: CCP2 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode.
REGISTER 9-6:
PIR3: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 3
R/W-0
R/W-0
U-0
U-0
U-0
U-0
U-0
U-0
SSP2IF
BCL2IF
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
SSP2IF: Master Synchronous Serial Port 2 Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
bit 6
BCL2IF: Bus Collision Interrupt Flag bit (MSSP2 module)
1 = A bus collision occurred (must be cleared in software)
0 = No bus collision occurred
bit 5-0
Unimplemented: Read as ‘0’
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS39682E-page 89
PIC18F45J10 FAMILY
9.3
PIE Registers
The PIE registers contain the individual enable bits for
the peripheral interrupts. Due to the number of
peripheral interrupt sources, there are three Peripheral
Interrupt Enable registers (PIE1, PIE2, PIE3). When
IPEN = 0, the PEIE bit must be set to enable any of
these peripheral interrupts.
REGISTER 9-7:
PIE1: PERIPHERAL INTERRUPT ENABLE REGISTER 1
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
PSPIE: Parallel Slave Port Read/Write Interrupt Enable bit(1)
1 = Enables the PSP read/write interrupt
0 = Disables the PSP read/write interrupt
bit 6
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
bit 5
RCIE: EUSART Receive Interrupt Enable bit
1 = Enables the EUSART receive interrupt
0 = Disables the EUSART receive interrupt
bit 4
TXIE: EUSART Transmit Interrupt Enable bit
1 = Enables the EUSART transmit interrupt
0 = Disables the EUSART transmit interrupt
bit 3
SSP1IE: Master Synchronous Serial Port 1 Interrupt Enable bit
1 = Enables the MSSP interrupt
0 = Disables the MSSP interrupt
bit 2
CCP1IE: ECCP1/CCP1 Interrupt Enable bit
1 = Enables the ECCP1/CCP1 interrupt
0 = Disables the ECCP1/CCP1 interrupt
bit 1
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
1 = Enables the TMR2 to PR2 match interrupt
0 = Disables the TMR2 to PR2 match interrupt
bit 0
TMR1IE: TMR1 Overflow Interrupt Enable bit
1 = Enables the TMR1 overflow interrupt
0 = Disables the TMR1 overflow interrupt
Note 1:
x = Bit is unknown
This bit is not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 90
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 9-8:
PIE2: PERIPHERAL INTERRUPT ENABLE REGISTER 2
R/W-0
R/W-0
U-0
U-0
R/W-0
U-0
U-0
R/W-0
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
OSCFIE: Oscillator Fail Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 6
CMIE: Comparator Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 5-4
Unimplemented: Read as ‘0’
bit 3
BCL1IE: Bus Collision Interrupt Enable bit (MSSP1 module)
1 = Enabled
0 = Disabled
bit 2-1
Unimplemented: Read as ‘0’
bit 0
CCP2IE: CCP2 Interrupt Enable bit
1 = Enabled
0 = Disabled
REGISTER 9-9:
x = Bit is unknown
PIE3: PERIPHERAL INTERRUPT ENABLE REGISTER 3
R/W-0
R/W-0
U-0
U-0
U-0
U-0
U-0
U-0
SSP2IE
BCL2IE
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
SSP2IE: Master Synchronous Serial Port 2 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 6
BCL2IE: Bus Collision Interrupt Enable bit (MSSP2 module)
1 = Enabled
0 = Disabled
bit 5-0
Unimplemented: Read as ‘0’
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS39682E-page 91
PIC18F45J10 FAMILY
9.4
IPR Registers
The IPR registers contain the individual priority bits for
the peripheral interrupts. Due to the number of
peripheral interrupt sources, there are three Peripheral
Interrupt Priority registers (IPR1, IPR2, IPR3). Using
the priority bits requires that the Interrupt Priority
Enable (IPEN) bit be set.
REGISTER 9-10:
IPR1: PERIPHERAL INTERRUPT PRIORITY REGISTER 1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
PSPIP: Parallel Slave Port Read/Write Interrupt Priority bit(1)
1 = High priority
0 = Low priority
bit 6
ADIP: A/D Converter Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
RCIP: EUSART Receive Interrupt Priority bit
1 = High priority
0 = Low priority
bit 4
TXIP: EUSART Transmit Interrupt Priority bit
x = Bit is unknown
1 = High priority
0 = Low priority
bit 3
SSP1IP: Master Synchronous Serial Port 1 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 2
CCP1IP: ECCP1/CCP1 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR2IP: TMR2 to PR2 Match Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
TMR1IP: TMR1 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
Note 1:
This bit is not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 92
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 9-11:
IPR2: PERIPHERAL INTERRUPT PRIORITY REGISTER 2
R/W-1
R/W-1
U-0
U-0
R/W-1
U-0
U-0
R/W-0
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
OSCFIP: Oscillator Fail Interrupt Priority bit
1 = High priority
0 = Low priority
bit 6
CMIP: Comparator Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5-4
Unimplemented: Read as ‘0’
bit 3
BCL1IP: Bus Collision Interrupt Priority bit (MSSP1 module)
1 = High priority
0 = Low priority
bit 2-1
Unimplemented: Read as ‘0’
bit 0
CCP2IP: CCP2 Interrupt Priority bit
1 = High priority
0 = Low priority
REGISTER 9-12:
x = Bit is unknown
IPR3: PERIPHERAL INTERRUPT PRIORITY REGISTER 3
R/W-1
R/W-1
U-0
U-0
U-0
U-0
U-0
U-0
SSP2IP
BCL2IP
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
SSP2IP: Master Synchronous Serial Port 2 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 6
BCL2IP: Bus Collision Interrupt Priority bit (MSSP2 module)
1 = High priority
0 = Low priority
bit 5-0
Unimplemented: Read as ‘0’
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS39682E-page 93
PIC18F45J10 FAMILY
9.5
RCON Register
The RCON register contains bits used to determine the
cause of the last Reset or wake-up from Idle or Sleep
modes. RCON also contains the bit that enables
interrupt priorities (IPEN).
REGISTER 9-13:
RCON: RESET CONTROL REGISTER
R/W-0
U-0
R/W-1
R/W-1
R-1
R-1
R/W-0
R/W-0
IPEN
—
CM
RI
TO
PD
POR
BOR
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode)
bit 6
Unimplemented: Read as ‘0’
bit 5
CM: Configuration Mismatch Flag bit
For details of bit operation, see Register 5-1.
bit 4
RI: RESET Instruction Flag bit
For details of bit operation, see Register 5-1.
bit 3
TO: Watchdog Timer Time-out Flag bit
For details of bit operation, see Register 5-1.
bit 2
PD: Power-Down Detection Flag bit
For details of bit operation, see Register 5-1.
bit 1
POR: Power-on Reset Status bit
For details of bit operation, see Register 5-1.
bit 0
BOR: Brown-out Reset Status bit
For details of bit operation, see Register 5-1.
DS39682E-page 94
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
9.6
INTx Pin Interrupts
9.7
External interrupts on the RB0/INT0, RB1/INT1 and
RB2/INT2 pins are edge-triggered. If the corresponding
INTEDGx bit in the INTCON2 register is set (= 1), the
interrupt is triggered by a rising edge; if the bit is clear,
the trigger is on the falling edge. When a valid edge
appears on the RBx/INTx pin, the corresponding flag
bit, INTxIF, is set. This interrupt can be disabled by
clearing the corresponding enable bit, INTxIE. Flag bit,
INTxIF, must be cleared in software in the Interrupt
Service Routine before re-enabling the interrupt.
All external interrupts (INT0, INT1 and INT2) can
wake-up the processor from the power-managed
modes if bit INTxIE was set prior to going into the
power-managed modes. If the Global Interrupt Enable
bit, GIE, is set, the processor will branch to the interrupt
vector following wake-up.
Interrupt priority for INT1 and INT2 is determined by the
value contained in the interrupt priority bits, INT1IP
(INTCON3<6>) and INT2IP (INTCON3<7>). There is
no priority bit associated with INT0. It is always a
high-priority interrupt source.
TMR0 Interrupt
In 8-bit mode (which is the default), an overflow in the
TMR0 register (FFh → 00h) will set flag bit, TMR0IF. In
16-bit mode, an overflow in the TMR0H:TMR0L register
pair (FFFFh → 0000h) will set TMR0IF. The interrupt
can be enabled/disabled by setting/clearing enable bit,
TMR0IE (INTCON<5>). Interrupt priority for Timer0 is
determined by the value contained in the interrupt priority bit, TMR0IP (INTCON2<2>). See Section 11.0
“Timer0 Module” for further details on the Timer0
module.
9.8
PORTB Interrupt-on-Change
An input change on PORTB<7:4> sets flag bit, RBIF
(INTCON<0>). The interrupt can be enabled/disabled
by setting/clearing enable bit, RBIE (INTCON<3>).
Interrupt priority for PORTB interrupt-on-change is
determined by the value contained in the interrupt
priority bit, RBIP (INTCON2<0>).
9.9
Context Saving During Interrupts
During interrupts, the return PC address is saved on
the stack. Additionally, the WREG, STATUS and BSR
registers are saved on the Fast Return Stack. If a fast
return from interrupt is not used (see Section 6.3
“Data Memory Organization”), the user may need to
save the WREG, STATUS and BSR registers on entry
to the Interrupt Service Routine. Depending on the
user’s application, other registers may also need to be
saved. Example 9-1 saves and restores the WREG,
STATUS and BSR registers during an Interrupt Service
Routine.
EXAMPLE 9-1:
SAVING STATUS, WREG AND BSR REGISTERS IN RAM
MOVWF
W_TEMP
MOVFF
STATUS, STATUS_TEMP
MOVFF
BSR, BSR_TEMP
;
; USER ISR CODE
;
MOVFF
BSR_TEMP, BSR
MOVF
W_TEMP, W
MOVFF
STATUS_TEMP, STATUS
© 2009 Microchip Technology Inc.
; W_TEMP is in virtual bank
; STATUS_TEMP located anywhere
; BSR_TMEP located anywhere
; Restore BSR
; Restore WREG
; Restore STATUS
DS39682E-page 95
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 96
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
10.0
I/O PORTS
10.1
I/O Port Pin Capabilities
Depending on the device selected and features
enabled, there are up to five ports available. Some pins
of the I/O ports are multiplexed with an alternate
function from the peripheral features on the device. In
general, when a peripheral is enabled, that pin may not
be used as a general purpose I/O pin.
When developing an application, the capabilities of the
port pins must be considered. Outputs on some pins
have higher output drive strength than others. Similarly,
some pins can tolerate higher than VDD input levels.
Each port has three registers for its operation. These
registers are:
The output pin drive strengths vary for groups of pins
intended to meet the needs for a variety of applications.
PORTB and PORTC are designed to drive higher
loads, such as LEDs. All other ports are designed for
small loads, typically indication only. Table 10-1 summarizes the output capabilities. Refer to Section 24.0
“Electrical Characteristics” for more details.
• TRIS register (Data Direction register)
• PORT register (reads the levels on the pins of the
device)
• LAT register (Data Latch register)
The Data Latch (LAT register) is useful for read-modifywrite operations on the value that the I/O pins are
driving.
10.1.1
TABLE 10-1:
Port
A simplified model of a generic I/O port, without the
interfaces to other peripherals, is shown in Figure 10-1.
PORTA
FIGURE 10-1:
PORTE
GENERIC I/O PORT
OPERATION
PIN OUTPUT DRIVE
PORTD
Drive
Data
Bus
PORTB
WR LAT
or PORT
10.1.2
D
Q
I/O pin
CK
Data Latch
D
WR TRIS
Q
CK
TRIS Latch
Input
Buffer
Description
Minimum Intended for indication.
High
PORTC
RD LAT
OUTPUT DRIVE LEVELS
Suitable for direct LED drive
levels.
INPUT PINS AND VOLTAGE
CONSIDERATIONS
The voltage tolerance of pins used as device inputs is
dependent on the pin’s input function. Pins that are used
as digital only inputs are able to handle DC voltages up
to 5.5V; a level typical for digital logic circuits. In contrast,
pins that also have analog input functions of any kind
can only tolerate voltages up to VDD. Voltage excursions
beyond VDD on these pins should be avoided. Table 102 summarizes the input capabilities. Refer to
Section 24.0 “Electrical Characteristics” for more
details.
RD TRIS
TABLE 10-2:
Q
D
Port or Pin
ENEN
RD PORT
INPUT VOLTAGE LEVELS
Tolerated
Input
Description
PORTA<5:0>
PORTB<5:0>
PORTC<1:0>
VDD
Only VDD input levels
tolerated.
5.5V
Tolerates input levels
above VDD, useful for
most standard logic.
PORTE<2:0>
PORTB<7:6>
PORTC<7:2>
PORTD<7:0>
© 2009 Microchip Technology Inc.
DS39682E-page 97
PIC18F45J10 FAMILY
10.1.3
INTERFACING TO A 5V SYSTEM
Though the VDDMAX of the PIC18F45J10 family is 3.6V,
these devices are still capable of interfacing with 5V
systems, even if the VIH of the target system is above
3.6V. This is accomplished by adding a pull-up resistor
to the port pin (Figure 10-2), clearing the LAT bit for that
pin and manipulating the corresponding TRIS bit
(Figure 10-1) to either allow the line to be pulled high or
to drive the pin low. Only port pins that are tolerant of
voltages up to 5.5V can be used for this type of
interface (refer to Section 10.1.2 “Input Pins and
Voltage Considerations”).
FIGURE 10-2:
+5V SYSTEM HARDWARE
INTERFACE
PIC18F45J10
+5V
+5V Device
10.2
PORTA is a 5-bit wide, bidirectional port. The corresponding Data Direction register is TRISA. Setting a
TRISA bit (= 1) will make the corresponding PORTA pin
an input (i.e., put the corresponding output driver in a
high-impedance mode). Clearing a TRISA bit (= 0) will
make the corresponding PORTA pin an output (i.e., put
the contents of the output latch on the selected pin).
Reading the PORTA register reads the status of the
pins, whereas writing to it, will write to the port latch.
The Data Latch (LATA) register is also memory mapped.
Read-modify-write operations on the LATA register read
and write the latched output value for PORTA.
The other PORTA pins are multiplexed with analog
inputs, the analog VREF+ and VREF- inputs and the comparator voltage reference output. The operation of pins
RA<3:0> and RA5 as A/D converter inputs is selected
by clearing or setting the control bits in the ADCON1
register (A/D Control Register 1).
Pins RA0 and RA3 may also be used as comparator
inputs and RA5 may be used as the C2 comparator
output by setting the appropriate bits in the CMCON
register. To use RA<3:0> as digital inputs, it is also
necessary to turn off the comparators.
RD7
Note:
EXAMPLE 10-1:
BCF
LATD, 7
BCF
BCF
TRISD, 7
TRISD, 7
PORTA, TRISA and LATA Registers
COMMUNICATING WITH
THE +5V SYSTEM
;
;
;
;
;
set up LAT register so
changing TRIS bit will
drive line low
send a 0 to the 5V system
send a 1 to the 5V system
On a Power-on Reset, RA5 and RA<3:0>
are configured as analog inputs and read
as ‘0’.
All PORTA pins have TTL input levels and full CMOS
output drivers.
The TRISA register controls the direction of the PORTA
pins, even when they are being used as analog inputs.
The user must ensure the bits in the TRISA register are
maintained set when using them as analog inputs.
EXAMPLE 10-2:
DS39682E-page 98
CLRF
PORTA
CLRF
LATA
MOVLW
MOVWF
MOVWF
MOVWF
MOVLW
07h
ADCON1
07h
CMCON
0CFh
MOVWF
TRISA
INITIALIZING PORTA
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTA by
clearing output
data latches
Alternate method
to clear output
data latches
Configure A/D
for digital inputs
Configure comparators
for digital input
Value used to
initialize data
direction
Set RA<3:0> as inputs
RA<5:4> as outputs
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 10-3:
Pin
RA0/AN0
RA1/AN1
RA2/AN2/
VREF-/CVREF
RA3/AN3/VREF+
RA5/AN4/SS1/
C2OUT
OSC2/CLKO
OSC1/CLKI
Legend:
PORTA I/O SUMMARY
Function
TRIS
Setting
I/O
I/O
Type
RA0
0
O
DIG
1
I
TTL
PORTA<0> data input; disabled when analog input enabled.
AN0
1
I
ANA
A/D Input Channel 0 and Comparator C1- input. Default input
configuration on POR; does not affect digital output.
RA1
0
O
DIG
LATA<1> data output; not affected by analog input.
1
I
TTL
PORTA<1> data input; disabled when analog input enabled.
AN1
1
I
ANA
A/D Input Channel 1 and Comparator C2- input. Default input
configuration on POR; does not affect digital output.
RA2
0
O
DIG
LATA<2> data output; not affected by analog input. Disabled when
CVREF output enabled.
1
I
TTL
PORTA<2> data input. Disabled when analog functions enabled;
disabled when CVREF output enabled.
AN2
1
I
ANA
A/D Input Channel 2 and Comparator C2+ input. Default input
configuration on POR; not affected by analog output.
VREF-
1
I
ANA
A/D and comparator voltage reference low input.
CVREF
x
O
ANA
Comparator voltage reference output. Enabling this feature disables
digital I/O.
RA3
0
O
DIG
LATA<3> data output; not affected by analog input.
Description
LATA<0> data output; not affected by analog input.
1
I
TTL
PORTA<3> data input; disabled when analog input enabled.
AN3
1
I
ANA
A/D Input Channel 3 and Comparator C1+ input. Default input
configuration on POR.
VREF+
1
I
ANA
A/D and comparator voltage reference high input.
RA5
0
O
DIG
LATA<5> data output; not affected by analog input.
1
I
TTL
PORTA<5> data input; disabled when analog input enabled.
A/D Input Channel 4. Default configuration on POR.
AN4
1
I
ANA
SS1
1
I
TTL
Slave select input for MSSP1 (MSSP1 module).
C2OUT
0
O
DIG
Comparator 2 output; takes priority over port data.
Main oscillator feedback output connection (HS mode).
OSC2
x
O
ANA
CLKO
x
O
DIG
System cycle clock output (FOSC/4) in RC and EC Oscillator modes.
OSC1
x
I
ANA
Main oscillator input connection.
CLKI
x
I
ANA
Main clock input connection.
DIG = Digital level output; TTL = TTL input buffer; ST = Schmitt Trigger input buffer; ANA = Analog level input/output;
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
© 2009 Microchip Technology Inc.
DS39682E-page 99
PIC18F45J10 FAMILY
TABLE 10-4:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PORTA
—
—
LATA
—
—
RA5
—
RA3
RA2
RA1
RA0
TRISA
—
—
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
PORTA Data Latch Register (Read and Write to Data Latch)
Reset
Values
on page
50
50
50
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
48
CMCON
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
49
CVRCON
CVREN
CVROE
CVRR
CVRSS
CVR3
CVR2
CVR1
CVR0
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTA.
DS39682E-page 100
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
10.3
PORTB, TRISB and LATB
Registers
PORTB is an 8-bit wide, bidirectional port. The corresponding Data Direction register is TRISB. Setting a
TRISB bit (= 1) will make the corresponding PORTB
pin an input (i.e., put the corresponding output driver in
a high-impedance mode). Clearing a TRISB bit (= 0)
will make the corresponding PORTB pin an output (i.e.,
put the contents of the output latch on the selected pin).
The Data Latch register (LATB) is also memory
mapped. Read-modify-write operations on the LATB
register read and write the latched output value for
PORTB.
EXAMPLE 10-3:
CLRF
PORTB
CLRF
LATB
MOVLW
MOVWF
MOVLW
0Fh
ADCON1
0CFh
MOVWF
TRISB
INITIALIZING PORTB
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTB by
clearing output
data latches
Alternate method
to clear output
data latches
Set RB<4:0> as
digital I/O pins
Value used to
initialize data
direction
Set RB<3:0> as inputs
RB<5:4> as outputs
RB<7:6> as inputs
Each of the PORTB pins has a weak internal pull-up. A
single control bit can turn on all the pull-ups. This is
performed by clearing bit, RBPU (INTCON2<7>). The
weak pull-up is automatically turned off when the port
pin is configured as an output. The pull-ups are
disabled on a Power-on Reset.
Note:
Four of the PORTB pins (RB<7:4>) have an interrupton-change feature. Only pins configured as inputs can
cause this interrupt to occur (i.e., any RB<7:4> pin
configured as an output is excluded from the interrupton-change comparison). The input pins (of RB<7:4>)
are compared with the old value latched on the last
read of PORTB. The “mismatch” outputs of RB<7:4>
are ORed together to generate the RB Port Change
Interrupt with Flag bit, RBIF (INTCON<0>).
This interrupt can wake the device from Sleep mode or
any of the Idle modes. The user, in the Interrupt Service
Routine, can clear the interrupt in the following manner:
a)
b)
Any read or write of PORTB (except with the
MOVFF (ANY), PORTB instruction).
Clear flag bit, RBIF.
A mismatch condition will continue to set flag bit, RBIF.
Reading PORTB will end the mismatch condition and
allow flag bit, RBIF, to be cleared.
The interrupt-on-change feature is recommended for
wake-up on key depression operation and operations
where PORTB is only used for the interrupt-on-change
feature. Polling of PORTB is not recommended while
using the interrupt-on-change feature.
RB3 can be configured by the Configuration bit,
CCP2MX, as the alternate peripheral pin for the CCP2
module (CCP2MX = 0).
The RB5 pin is multiplexed with the Timer0 module
clock input and one of the comparator outputs to
become the RB5/KBI1/T0CKI/C1OUT pin.
On a Power-on Reset, RB<4:0> are
configured as analog inputs by default and
read as ‘0’; RB<7:5> are configured as
digital inputs.
© 2009 Microchip Technology Inc.
DS39682E-page 101
PIC18F45J10 FAMILY
TABLE 10-5:
Pin
PORTB I/O SUMMARY
Function
TRIS
Setting
I/O
RB0
0
O
DIG
LATB<0> data output; not affected by analog input.
1
I
TTL
PORTB<0> data input; weak pull-up when RBPU bit is cleared.
Disabled when analog input enabled.(1)
RB0/INT0/FLT0/
AN12
RB1/INT1/AN10
RB2/INT2/AN8
RB3/AN9/CCP2
INT0
1
I
ST
External Interrupt 0 input.
1
I
ST
PWM Fault input (ECCP1/CCP1 module); enabled in
software.
AN12
1
I
ANA
A/D Input Channel 12.(1)
RB1
0
O
DIG
LATB<1> data output; not affected by analog input.
1
I
TTL
PORTB<1> data input; weak pull-up when RBPU bit is cleared.
Disabled when analog input enabled.(1)
INT1
1
I
ST
External Interrupt 1 input.
AN10
1
I
ANA
A/D Input Channel 10.(1)
RB2
0
O
DIG
LATB<2> data output; not affected by analog input.
1
I
TTL
PORTB<2> data input; weak pull-up when RBPU bit is cleared.
Disabled when analog input enabled.(1)
INT2
1
I
ST
AN8
1
I
ANA
RB3
0
O
DIG
LATB<3> data output; not affected by analog input.
1
I
TTL
PORTB<3> data input; weak pull-up when RBPU bit is cleared.
Disabled when analog input enabled.(1)
1
I
ANA
A/D Input Channel 9.(1)
0
O
DIG
CCP2 compare and PWM output.
1
I
ST
CCP2 capture input
0
O
DIG
LATB<4> data output; not affected by analog input.
1
I
TTL
PORTB<4> data input; weak pull-up when RBPU bit is cleared.
Disabled when analog input enabled.(1)
CCP2
RB5/KBI1/T0CKI/
C1OUT
RB6/KBI2/PGC
RB7/KBI3/PGD
Legend:
Note 1:
2:
3:
Description
FLT0
AN9
RB4/KBI0/AN11
I/O
Type
(2)
RB4
External Interrupt 2 input.
A/D Input Channel 8.(1)
KBI0
1
I
TTL
Interrupt-on-change pin.
AN11
1
I
ANA
A/D Input Channel 11.(1)
RB5
0
O
DIG
LATB<5> data output.
1
I
TTL
PORTB<5> data input; weak pull-up when RBPU bit is cleared.
KBI1
1
I
TTL
Interrupt-on-change pin.
T0CKI
1
I
ST
Timer0 clock input.
C1OUT
0
O
DIG
Comparator 1 output; takes priority over port data.
RB6
0
O
DIG
LATB<6> data output.
PORTB<6> data input; weak pull-up when RBPU bit is cleared.
1
I
TTL
KBI2
1
I
TTL
Interrupt-on-change pin.
PGC
x
I
ST
Serial execution (ICSP™) clock input for ICSP and ICD operation.(3)
RB7
0
O
DIG
LATB<7> data output.
1
I
TTL
PORTB<7> data input; weak pull-up when RBPU bit is cleared.
KBI3
1
I
TTL
Interrupt-on-change pin.
PGD
x
O
DIG
Serial execution data output for ICSP and ICD operation.(3)
x
I
ST
Serial execution data input for ICSP and ICD operation.(3)
DIG = Digital level output; TTL = TTL input buffer; ST = Schmitt Trigger input buffer; ANA = Analog level input/output;
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Pins are configured as analog inputs by default.
Alternate assignment for CCP2 when the CCP2MX Configuration bit is ‘0’. Default assignment is RC1.
All other pin functions are disabled when ICSP™ or ICD are enabled.
DS39682E-page 102
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 10-6:
Name
PORTB
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
50
LATB
PORTB Data Latch Register (Read and Write to Data Latch)
50
TRISB
PORTB Data Direction Control Register
50
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
INTEDG0 INTEDG1 INTEDG2
RBIE
TMR0IF
INT0IF
RBIF
47
—
TMR0IP
—
RBIP
47
INTCON2
RBPU
INTCON3
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
47
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
48
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTB.
© 2009 Microchip Technology Inc.
DS39682E-page 103
PIC18F45J10 FAMILY
10.4
PORTC, TRISC and LATC
Registers
PORTC is an 8-bit wide, bidirectional port. The corresponding Data Direction register is TRISC. Setting a
TRISC bit (= 1) will make the corresponding PORTC
pin an input (i.e., put the corresponding output driver in
a high-impedance mode). Clearing a TRISC bit (= 0)
will make the corresponding PORTC pin an output (i.e.,
put the contents of the output latch on the selected pin).
The Data Latch register (LATC) is also memory
mapped. Read-modify-write operations on the LATC
register read and write the latched output value for
PORTC.
PORTC is multiplexed with several peripheral functions
(Table 10-7). The pins have Schmitt Trigger input
buffers. RC1 is normally configured by Configuration
bit, CCP2MX, as the default peripheral pin of the CCP2
module (default/erased state, CCP2MX = 1).
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. Some
peripherals override the TRIS bit to make a pin an output,
while other peripherals override the TRIS bit to make a
pin an input. The user should refer to the corresponding
peripheral section for additional information.
DS39682E-page 104
Note:
On a Power-on Reset, these pins are
configured as digital inputs.
The contents of the TRISC register are affected by
peripheral overrides. Reading TRISC always returns
the current contents, even though a peripheral device
may be overriding one or more of the pins.
EXAMPLE 10-4:
CLRF
PORTC
CLRF
LATC
MOVLW 0CFh
MOVWF TRISC
INITIALIZING PORTC
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTC by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RC<3:0> as inputs
RC<5:4> as outputs
RC<7:6> as inputs
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 10-7:
Pin
RC0/T1OSO/
T1CKI
RC1/T1OSI/CCP2
RC2/CCP1/P1A
RC3/SCK1/SCL1
PORTC I/O SUMMARY
Function
TRIS
Setting
I/O
I/O
Type
RC0
0
O
DIG
1
I
ST
T1OSO
x
O
ANA
T1CKI
1
I
ST
Timer1 counter input.
RC1
0
O
DIG
LATC<1> data output.
1
I
ST
PORTC<1> data input.
T1OSI
x
I
ANA
Timer1 oscillator input; enabled when Timer1 oscillator enabled.
Disables digital I/O.
CCP2(1)
0
O
DIG
CCP2 compare and PWM output; takes priority over port data.
RC6/TX/CK
RC7/RX/DT
Legend:
Note 1:
2:
PORTC<0> data input.
Timer1 oscillator output; enabled when Timer1 oscillator enabled.
Disables digital I/O.
I
ST
CCP2 capture input.
0
O
DIG
LATC<2> data output.
1
I
ST
PORTC<2> data input.
CCP1
0
O
DIG
ECCP1/CCP1 compare or PWM output; takes priority over port data.
1
I
ST
ECCP1/CCP1 capture input.
P1A(2)
0
O
DIG
ECCP1 Enhanced PWM output, channel A. May be configured for
tri-state during Enhanced PWM shutdown events. Takes priority over
port data.
RC3
0
O
DIG
LATC<3> data output.
1
I
ST
PORTC<3> data input.
0
O
DIG
SPI clock output (MSSP1 module); takes priority over port data.
1
I
ST
SPI clock input (MSSP1 module).
0
O
DIG
I2C™ clock output (MSSP1 module); takes priority over port data.
1
I
0
O
DIG
1
I
ST
PORTC<4> data input.
SDI1
1
I
ST
SPI data input (MSSP1 module).
SDA1
1
O
DIG
I2C data output (MSSP1 module); takes priority over port data.
SCL1
RC5/SDO1
LATC<0> data output.
1
RC2
SCK1
RC4/SDI1/SDA1
Description
RC4
I2C/SMB I2C clock input (MSSP1 module); input type depends on module setting.
LATC<4> data output.
2
I C/SMB I2C data input (MSSP1 module); input type depends on module setting.
1
I
0
O
DIG
1
I
ST
PORTC<5> data input.
SDO1
0
O
DIG
SPI data output (MSSP1 module); takes priority over port data.
RC6
0
O
DIG
LATC<6> data output.
1
I
ST
PORTC<6> data input.
TX
1
O
DIG
Asynchronous serial transmit data output (EUSART module);
takes priority over port data. User must configure as output.
CK
1
O
DIG
Synchronous serial clock output (EUSART module); takes priority
over port data.
RC5
RC7
LATC<5> data output.
1
I
ST
Synchronous serial clock input (EUSART module).
0
O
DIG
LATC<7> data output.
1
I
ST
PORTC<7> data input.
RX
1
I
ST
Asynchronous serial receive data input (EUSART module).
DT
1
O
DIG
Synchronous serial data output (EUSART module); takes priority over
port data.
1
I
ST
Synchronous serial data input (EUSART module). User must
configure as an input.
DIG = Digital level output; TTL = TTL input buffer; ST = Schmitt Trigger input buffer; ANA = Analog level input/output;
I2C™/SMB = I2C/SMBus input buffer; x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
Default assignment for CCP2 when the CCP2MX Configuration bit is set. Alternate assignment is RB3.
Enhanced PWM output is available only on PIC18F44J10/45J10 devices.
© 2009 Microchip Technology Inc.
DS39682E-page 105
PIC18F45J10 FAMILY
TABLE 10-8:
Name
PORTC
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
50
LATC
PORTC Data Latch Register (Read and Write to Data Latch)
50
TRISC
PORTC Data Direction Control Register
50
DS39682E-page 106
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
10.5
Note:
PORTD, TRISD and LATD
Registers
PORTD is only available in 40/44-pin
devices.
PORTD is an 8-bit wide, bidirectional port. The corresponding Data Direction register is TRISD. Setting a
TRISD bit (= 1) will make the corresponding PORTD
pin an input (i.e., put the corresponding output driver in
a high-impedance mode). Clearing a TRISD bit (= 0)
will make the corresponding PORTD pin an output (i.e.,
put the contents of the output latch on the selected pin).
The Data Latch register (LATD) is also memory
mapped. Read-modify-write operations on the LATD
register read and write the latched output value for
PORTD.
All pins on PORTD are implemented with Schmitt Trigger
input buffers. Each pin is individually configurable as an
input or output.
Three of the PORTD pins are multiplexed with outputs
P1B, P1C and P1D of the Enhanced CCP module. The
operation of these additional PWM output pins is
covered in greater detail in Section 15.0 “Enhanced
Capture/Compare/PWM (ECCP) Module”.
Note:
PORTD can also be configured as an 8-bit wide microprocessor port (Parallel Slave Port) by setting control
bit, PSPMODE (TRISE<4>). In this mode, the input
buffers are TTL. See Section 10.7 “Parallel Slave
Port” for additional information on the Parallel Slave
Port (PSP).
Note:
When the Enhanced PWM mode is used
with either dual or quad outputs, the PSP
functions of PORTD are automatically
disabled.
EXAMPLE 10-5:
CLRF
PORTD
CLRF
LATD
MOVLW 0CFh
MOVWF TRISD
INITIALIZING PORTD
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTD by
clearing output
data latches
Alternate method
to clear output
data latches
Value used to
initialize data
direction
Set RD<3:0> as inputs
RD<5:4> as outputs
RD<7:6> as inputs
On a Power-on Reset, these pins are
configured as digital inputs.
© 2009 Microchip Technology Inc.
DS39682E-page 107
PIC18F45J10 FAMILY
TABLE 10-9:
PORTD I/O SUMMARY
Pin
Function
RD0/PSP0/SCK2/
SCL2
RD0
DIG
LATD<0> data output.
I
ST
PORTD<0> data input.
x
O
DIG
PSP read data output (LATD<0>); takes priority over port data.
x
I
TTL
PSP write data input.
SCK2
0
O
DIG
SPI clock output (MSSP2 module); takes priority over port data.
1
I
ST
SPI clock input (MSSP2 module).
SCL2
0
O
DIG
I2C™ clock output (MSSP2 module); takes priority over port data.
1
I
0
O
DIG
1
I
ST
PORTD<1> data input.
x
O
DIG
PSP read data output (LATD<1>); takes priority over port data.
RD1
RD5/PSP5/P1B
RD7/PSP7/P1D
Legend:
LATD<1> data output.
x
I
TTL
PSP write data input.
1
I
ST
SPI data input (MSSP2 module).
SDA2
1
O
DIG
I2C data output (MSSP2 module); takes priority over port data.
1
I
2C/SMB
0
O
DIG
1
I
ST
PORTD<2> data input.
x
O
DIG
PSP read data output (LATD<2>); takes priority over port data.
RD2
RD3
I
I2C data input (MSSP2 module); input type depends on module setting.
LATD<2> data output.
x
I
TTL
PSP write data input.
0
O
DIG
SPI data output (MSSP2 module); takes priority over port data.
LATD<3> data output.
0
O
DIG
1
I
ST
PORTD<3> data input.
PSP3
x
O
DIG
PSP read data output (LATD<3>); takes priority over port data.
x
I
TTL
PSP write data input.
SS2
1
I
TTL
Slave select input for MSSP2 (MSSP2 module).
RD4
0
O
DIG
LATD<4> data output.
1
I
ST
PORTD<4> data input.
PSP4
x
O
DIG
PSP read data output (LATD<4>); takes priority over port data.
x
I
TTL
PSP write data input.
RD5
0
O
DIG
LATD<5> data output.
PSP5
RD6/PSP6/P1C
I2C/SMB I2C clock input (MSSP2 module); input type depends on module setting.
SDI2
SDO2
RD4/PSP4
Description
O
PSP2
RD3/PSP3/SS2
I/O
Type
0
PSP1
RD2/PSP2/SDO2
I/O
1
PSP0
RD1/PSP1/SDI2/
SDA2
TRIS
Setting
1
I
ST
PORTD<5> data input.
x
O
DIG
PSP read data output (LATD<5>); takes priority over port data.
x
I
TTL
PSP write data input.
P1B
0
O
DIG
ECCP1 Enhanced PWM output, Channel B; takes priority over port and PSP
data. May be configured for tri-state during Enhanced PWM shutdown events.
RD6
0
O
DIG
LATD<6> data output.
1
I
ST
PORTD<6> data input.
PSP6
x
O
DIG
PSP read data output (LATD<6>); takes priority over port data.
x
I
TTL
PSP write data input.
P1C
0
O
DIG
ECCP1 Enhanced PWM output, Channel C; takes priority over port and PSP
data. May be configured for tri-state during Enhanced PWM shutdown events.
RD7
0
O
DIG
LATD<7> data output.
1
I
ST
PORTD<7> data input.
PSP7
x
O
DIG
PSP read data output (LATD<7>); takes priority over port data.
x
I
TTL
PSP write data input.
P1D
0
O
DIG
ECCP1 Enhanced PWM output, Channel D; takes priority over port and PSP
data. May be configured for tri-state during Enhanced PWM shutdown events.
DIG = Digital level output; TTL = TTL input buffer; ST = Schmitt Trigger input buffer; I2C™/SMB = I2C/SMBus input buffer;
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
DS39682E-page 108
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 10-10: SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
Name
PORTD(1)
(1)
LATD
TRISD(1)
(1)
TRISE
CCP1CON
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
Reset
Values
on page
50
PORTD Data Latch Register (Read and Write to Data Latch)
50
PORTD Data Direction Control Register
50
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
50
P1M1(1)
P1M0(1)
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTD.
Note 1: These registers and/or bits are not available in 28-pin devices.
© 2009 Microchip Technology Inc.
DS39682E-page 109
PIC18F45J10 FAMILY
10.6
Note:
PORTE, TRISE and LATE
Registers
PORTE is only available in 40/44-pin
devices.
Depending on the particular PIC18F45J10 family
device selected, PORTE is implemented in two
different ways.
For 40/44-pin devices, PORTE is a 4-bit wide port.
Three pins (RE0/RD/AN5, RE1/WR/AN6 and RE2/CS/
AN7) are individually configurable as inputs or outputs.
These pins have Schmitt Trigger input buffers. When
selected as analog inputs, these pins will read as ‘0’s.
The corresponding Data Direction register is TRISE.
Setting a TRISE bit (= 1) will make the corresponding
PORTE pin an input (i.e., put the corresponding output
driver in a high-impedance mode). Clearing a TRISE bit
(= 0) will make the corresponding PORTE pin an output
(i.e., put the contents of the output latch on the selected
pin).
TRISE controls the direction of the RE pins, even when
they are being used as analog inputs. The user must
make sure to keep the pins configured as inputs when
using them as analog inputs.
Note:
The upper four bits of the TRISE register also control
the operation of the Parallel Slave Port. Their operation
is explained in Register 10-1.
The Data Latch register (LATE) is also memory
mapped. Read-modify-write operations on the LATE
register read and write the latched output value for
PORTE.
EXAMPLE 10-6:
CLRF
PORTE
CLRF
LATE
MOVLW
MOVWF
MOVLW
0Ah
ADCON1
03h
MOVWF
TRISE
INITIALIZING PORTE
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Initialize PORTE by
clearing output
data latches
Alternate method
to clear output
data latches
Configure A/D
for digital inputs
Value used to
initialize data
direction
Set RE<0> as inputs
RE<1> as outputs
RE<2> as inputs
On a Power-on Reset, RE<2:0> are
configured as analog inputs.
DS39682E-page 110
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 10-1:
TRISE REGISTER (40/44-PIN DEVICES ONLY)
R-0
R-0
R/W-0
R/W-0
U-0
R/W-1
R/W-1
R/W-1
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
IBF: Input Buffer Full Status bit
1 = A word has been received and is waiting to be read by the CPU
0 = No word has been received
bit 6
OBF: Output Buffer Full Status bit
1 = The output buffer still holds a previously written word
0 = The output buffer has been read
bit 5
IBOV: Input Buffer Overflow Detect bit (in Microprocessor mode)
1 = A write occurred when a previously input word has not been read (must be cleared in software)
0 = No overflow occurred
bit 4
PSPMODE: Parallel Slave Port Mode Select bit
1 = Parallel Slave Port mode
0 = General Purpose I/O mode
bit 3
Unimplemented: Read as ‘0’
bit 2
TRISE2: RE2 Direction Control bit
1 = Input
0 = Output
bit 1
TRISE1: RE1 Direction Control bit
1 = Input
0 = Output
bit 0
TRISE0: RE0 Direction Control bit
1 = Input
0 = Output
© 2009 Microchip Technology Inc.
DS39682E-page 111
PIC18F45J10 FAMILY
TABLE 10-11: PORTE I/O SUMMARY
Pin
Function
TRIS
Setting
I/O
I/O
Type
RE0
0
O
DIG
LATE<0> data output; not affected by analog input.
1
I
ST
PORTE<0> data input; disabled when analog input enabled.
RE0/RD/AN5
RE1/WR/AN6
RE2/CS/AN7
Legend:
Description
RD
1
I
TTL
PSP read enable input (PSP enabled).
AN5
1
I
ANA
A/D Input Channel 5; default input configuration on POR.
RE1
0
O
DIG
LATE<1> data output; not affected by analog input.
1
I
ST
PORTE<1> data input; disabled when analog input enabled.
WR
1
I
TTL
PSP write enable input (PSP enabled).
AN6
1
I
ANA
A/D Input Channel 6; default input configuration on POR.
RE2
0
O
DIG
LATE<2> data output; not affected by analog input.
1
I
ST
PORTE<2> data input; disabled when analog input enabled.
CS
1
I
TTL
PSP write enable input (PSP enabled).
AN7
1
I
ANA
A/D Input Channel 7; default input configuration on POR.
DIG = Digital level output; TTL = TTL input buffer; ST = Schmitt Trigger input buffer; ANA = Analog level input/output;
x = Don’t care (TRIS bit does not affect port direction or is overridden for this option).
TABLE 10-12: SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
PORTE(1)
—
—
—
—
—
RE2
RE1
RE0
50
LATE(1)
—
—
—
—
—
PORTE Data Latch Register
(Read and Write to Data Latch)
50
TRISE(1)
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
50
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
48
Name
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTE.
Note 1: These registers are not available in 28-pin devices.
DS39682E-page 112
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
10.7
Note:
Parallel Slave Port
The Parallel Slave Port is only available in
40/44-pin devices.
In addition to its function as a general I/O port, PORTD
can also operate as an 8-bit wide Parallel Slave Port
(PSP) or microprocessor port. PSP operation is
controlled by the 4 upper bits of the TRISE register
(Register 10-1). Setting control bit, PSPMODE
(TRISE<4>), enables PSP operation as long as the
Enhanced CCP module is not operating in Dual Output
or Quad Output PWM mode. In Slave mode, the port is
asynchronously readable and writable by the external
world.
The PSP can directly interface to an 8-bit microprocessor data bus. The external microprocessor can
read or write the PORTD latch as an 8-bit latch. Setting
the control bit, PSPMODE, enables the PORTE I/O
pins to become control inputs for the microprocessor
port. When set, port pin RE0 is the RD input, RE1 is the
WR input and RE2 is the CS (Chip Select) input. For
this functionality, the corresponding data direction bits
of the TRISE register (TRISE<2:0>) must be configured as inputs (set). The A/D port configuration bits,
PFCG<3:0> (ADCON1<3:0>), must also be set to a
value in the range of ‘1010’ through ‘1111’.
The timing for the control signals in Write and Read
modes is shown in Figure 10-4 and Figure 10-5,
respectively.
FIGURE 10-3:
One bit of PORTD
Data Bus
WR LATD
or
WR PORTD
Q
RDx pin
CK
Data Latch
RD PORTD
TTL
D
ENEN
RD LATD
Set Interrupt Flag
PSPIF (PIR1<7>)
PORTE Pins
Read
A read from the PSP occurs when both the CS and RD
lines are first detected low. The data in PORTD is read
out and the OBF bit is clear. If the user writes new data
to PORTD to set OBF, the data is immediately read out;
however, the OBF bit is not set.
© 2009 Microchip Technology Inc.
D
Q
A write to the PSP occurs when both the CS and WR
lines are first detected low and ends when either are
detected high. The PSPIF and IBF flag bits are both set
when the write ends.
When either the CS or RD lines are detected high, the
PORTD pins return to the input state and the PSPIF bit
is set. User applications should wait for PSPIF to be set
before servicing the PSP; when this happens, the IBF
and OBF bits can be polled and the appropriate action
taken.
PORTD AND PORTE
BLOCK DIAGRAM
(PARALLEL SLAVE PORT)
TTL
RD
Chip Select
TTL
CS
Write
Note:
TTL
WR
I/O pins have diode protection to VDD and VSS.
DS39682E-page 113
PIC18F45J10 FAMILY
FIGURE 10-4:
PARALLEL SLAVE PORT WRITE WAVEFORMS
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q4
Q1
Q2
Q3
Q4
CS
WR
RD
PORTD<7:0>
IBF
OBF
PSPIF
FIGURE 10-5:
PARALLEL SLAVE PORT READ WAVEFORMS
Q1
Q2
Q3
Q4
Q1
Q2
Q3
CS
WR
RD
PORTD<7:0>
IBF
OBF
PSPIF
TABLE 10-13: REGISTERS ASSOCIATED WITH PARALLEL SLAVE PORT
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
PORTD(1)
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
50
LATD(1)
PORTD Data Latch Register (Read and Write to Data Latch)
50
TRISD(1)
PORTD Data Direction Control Register
50
(1)
PORTE
—
—
—
—
—
LATE(1)
—
—
—
—
—
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
50
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
TRISE(1)
INTCON
GIE/GIEH PEIE/GIEL
RE0
50
PORTE Data Latch Register
(Read and Write to Data Latch)
RE2
RE1
50
PIR1
(1)
PSPIF
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
48
ADCON1
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Parallel Slave Port.
Note 1: These registers and/or bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 114
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
11.0
TIMER0 MODULE
The Timer0 module incorporates the following features:
• Software selectable operation as a timer or
counter in both 8-bit or 16-bit modes
• Readable and writable registers
• Dedicated 8-bit, software programmable
prescaler
• Selectable clock source (internal or external)
• Edge select for external clock
• Interrupt-on-overflow
REGISTER 11-1:
The T0CON register (Register 11-1) controls all
aspects of the module’s operation, including the
prescale selection. It is both readable and writable.
A simplified block diagram of the Timer0 module in 8-bit
mode is shown in Figure 11-1. Figure 11-2 shows a
simplified block diagram of the Timer0 module in 16-bit
mode.
T0CON: TIMER0 CONTROL REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
TMR0ON
T08BIT
T0CS
T0SE
PSA
T0PS2
T0PS1
T0PS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
TMR0ON: Timer0 On/Off Control bit
1 = Enables Timer0
0 = Stops Timer0
bit 6
T08BIT: Timer0 8-Bit/16-Bit Control bit
1 = Timer0 is configured as an 8-bit timer/counter
0 = Timer0 is configured as a 16-bit timer/counter
bit 5
T0CS: Timer0 Clock Source Select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (CLKO)
bit 4
T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on T0CKI pin
0 = Increment on low-to-high transition on T0CKI pin
bit 3
PSA: Timer0 Prescaler Assignment bit
1 = TImer0 prescaler is not assigned. Timer0 clock input bypasses prescaler.
0 = Timer0 prescaler is assigned. Timer0 clock input comes from prescaler output.
bit 2-0
T0PS<2:0>: Timer0 Prescaler Select bits
111 = 1:256 Prescale value
110 = 1:128 Prescale value
101 = 1:64 Prescale value
100 = 1:32 Prescale value
011 = 1:16 Prescale value
010 = 1:8 Prescale value
001 = 1:4 Prescale value
000 = 1:2 Prescale value
© 2009 Microchip Technology Inc.
DS39682E-page 115
PIC18F45J10 FAMILY
11.1
Timer0 Operation
Timer0 can operate as either a timer or a counter; the
mode is selected with the T0CS bit (T0CON<5>). In
Timer mode (T0CS = 0), the module increments on
every clock by default unless a different prescaler value
is selected (see Section 11.3 “Prescaler”). If the
TMR0 register is written to, the increment is inhibited
for the following two instruction cycles. The user can
work around this by writing an adjusted value to the
TMR0 register.
The Counter mode is selected by setting the T0CS bit
(= 1). In this mode, Timer0 increments either on every
rising or falling edge of pin RB5/T0CKI. The incrementing edge is determined by the Timer0 Source Edge
Select bit, T0SE (T0CON<4>); clearing this bit selects
the rising edge. Restrictions on the external clock input
are discussed below.
An external clock source can be used to drive Timer0;
however, it must meet certain requirements to ensure
that the external clock can be synchronized with the
FIGURE 11-1:
internal phase clock (TOSC). There is a delay between
synchronization and the onset of incrementing the
timer/counter.
11.2
Timer0 Reads and Writes in
16-Bit Mode
TMR0H is not the actual high byte of Timer0 in 16-bit
mode. It is actually a buffered version of the real high
byte of Timer0 which is not directly readable nor
writable (refer to Figure 11-2). TMR0H is updated with
the contents of the high byte of Timer0 during a read of
TMR0L. This provides the ability to read all 16 bits of
Timer0 without having to verify that the read of the high
and low byte were valid, due to a rollover between
successive reads of the high and low byte.
Similarly, a write to the high byte of Timer0 must also
take place through the TMR0H Buffer register. The high
byte is updated with the contents of TMR0H when a
write occurs to TMR0L. This allows all 16 bits of Timer0
to be updated at once.
TIMER0 BLOCK DIAGRAM (8-BIT MODE)
FOSC/4
0
1
1
Programmable
Prescaler
T0CKI pin
T0SE
T0CS
0
Sync with
Internal
Clocks
(2 TCY Delay)
8
3
T0PS<2:0>
8
PSA
Note:
Set
TMR0IF
on Overflow
TMR0L
Internal Data Bus
Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
FIGURE 11-2:
FOSC/4
TIMER0 BLOCK DIAGRAM (16-BIT MODE)
0
1
1
T0CKI pin
T0SE
T0CS
Programmable
Prescaler
0
Sync with
Internal
Clocks
TMR0
High Byte
TMR0L
8
Set
TMR0IF
on Overflow
(2 TCY Delay)
3
Read TMR0L
T0PS<2:0>
Write TMR0L
PSA
8
8
TMR0H
8
8
Internal Data Bus
Note:
Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
DS39682E-page 116
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
11.3
11.3.1
Prescaler
An 8-bit counter is available as a prescaler for the Timer0
module. The prescaler is not directly readable or writable.
Its value is set by the PSA and T0PS<2:0> bits
(T0CON<3:0>) which determine the prescaler
assignment and prescale ratio.
Clearing the PSA bit assigns the prescaler to the
Timer0 module. When it is assigned, prescale values
from 1:2 through 1:256 in power-of-2 increments are
selectable.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g., CLRF TMR0, MOVWF
TMR0, BSF TMR0, etc.) clear the prescaler count.
Note:
Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler
count but will not change the prescaler
assignment.
TABLE 11-1:
Name
SWITCHING PRESCALER
ASSIGNMENT
The prescaler assignment is fully under software
control and can be changed “on-the-fly” during program
execution.
11.4
Timer0 Interrupt
The TMR0 interrupt is generated when the TMR0
register overflows from FFh to 00h in 8-bit mode, or
from FFFFh to 0000h in 16-bit mode. This overflow sets
the TMR0IF flag bit. The interrupt can be masked by
clearing the TMR0IE bit (INTCON<5>). Before
re-enabling the interrupt, the TMR0IF bit must be
cleared in software by the Interrupt Service Routine.
Since Timer0 is shut down in Sleep mode, the TMR0
interrupt cannot awaken the processor from Sleep.
REGISTERS ASSOCIATED WITH TIMER0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
TMR0L
Timer0 Register Low Byte
TMR0H
Timer0 Register High Byte
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
T0CON
TMR0ON
T08BIT
T0CS
T0SE
PSA
T0PS2
TRISA
—
—
TRISA5
—
TRISA3
TRISA2
Bit 1
Bit 0
Reset
Values
on page
48
48
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
T0PS1
T0PS0
48
TRISA1
TRISA0
50
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Timer0.
© 2009 Microchip Technology Inc.
DS39682E-page 117
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 118
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
12.0
TIMER1 MODULE
The Timer1 timer/counter module incorporates these
features:
• Software selectable operation as a 16-bit timer or
counter
• Readable and writable 8-bit registers (TMR1H
and TMR1L)
• Selectable clock source (internal or external) with
device clock or Timer1 oscillator internal options
• Interrupt-on-overflow
• Reset on CCP Special Event Trigger
• Device clock status flag (T1RUN)
REGISTER 12-1:
A simplified block diagram of the Timer1 module is
shown in Figure 12-1. A block diagram of the module’s
operation in Read/Write mode is shown in Figure 12-2.
The module incorporates its own low-power oscillator
to provide an additional clocking option. The Timer1
oscillator can also be used as a low-power clock source
for the microcontroller in power-managed operation.
Timer1 can also be used to provide Real-Time Clock
(RTC) functionality to applications with only a minimal
addition of external components and code overhead.
Timer1 is controlled through the T1CON Control
register (Register 12-1). It also contains the Timer1
Oscillator Enable bit (T1OSCEN). Timer1 can be
enabled or disabled by setting or clearing control bit,
TMR1ON (T1CON<0>).
T1CON: TIMER1 CONTROL REGISTER
R/W-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
RD16
T1RUN
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
RD16: 16-Bit Read/Write Mode Enable bit
1 = Enables register read/write of TImer1 in one 16-bit operation
0 = Enables register read/write of Timer1 in two 8-bit operations
bit 6
T1RUN: Timer1 System Clock Status bit
1 = Device clock is derived from Timer1 oscillator
0 = Device clock is derived from another source
bit 5-4
T1CKPS<1:0>: Timer1 Input Clock Prescale Select bits
11 = 1:8 Prescale value
10 = 1:4 Prescale value
01 = 1:2 Prescale value
00 = 1:1 Prescale value
bit 3
T1OSCEN: Timer1 Oscillator Enable bit
1 = Timer1 oscillator is enabled
0 = Timer1 oscillator is shut off
The oscillator inverter and feedback resistor are turned off to eliminate power drain.
bit 2
T1SYNC: Timer1 External Clock Input Synchronization Select bit
When TMR1CS = 1:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
When TMR1CS = 0:
This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0.
bit 1
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from pin RC0/T1OSO/T13CKI (on the rising edge)
0 = Internal clock (FOSC/4)
bit 0
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
© 2009 Microchip Technology Inc.
DS39682E-page 119
PIC18F45J10 FAMILY
12.1
When Timer1 is enabled, the RC1/T1OSI and
RC0/T1OSO/T1CKI pins become inputs. This means
the values of TRISC<1:0> are ignored and the pins are
read as ‘0’.
Timer1 Operation
Timer1 can operate in one of these modes:
• Timer
• Synchronous Counter
• Asynchronous Counter
The operating mode is determined by the clock select
bit, TMR1CS (T1CON<1>). When TMR1CS is cleared
(= 0), Timer1 increments on every internal instruction
cycle (FOSC/4). When the bit is set, Timer1 increments
on every rising edge of the Timer1 external clock input
or the Timer1 oscillator, if enabled.
FIGURE 12-1:
TIMER1 BLOCK DIAGRAM
Timer1 Clock Input
Timer1 Oscillator
On/Off
T1OSO/T1CKI
1
1
FOSC/4
Internal
Clock
T1OSI
Synchronize
Prescaler
1, 2, 4, 8
Detect
0
2
T1OSCEN(1)
0
Sleep Input
TMR1CS
T1CKPS<1:0>
Timer1
On/Off
T1SYNC
TMR1ON
Clear TMR1
(CCP Special Event Trigger)
TMR1L
TMR1
High Byte
Set
TMR1IF
on Overflow
Note 1: When enable bit, T1OSCEN, is cleared, the inverter and feedback resistor are turned off to eliminate power drain.
DS39682E-page 120
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 12-2:
TIMER1 BLOCK DIAGRAM (16-BIT READ/WRITE MODE)
Timer1 Clock Input
Timer1 Oscillator
1
T1OSO/T1CKI
1
FOSC/4
Internal
Clock
T1OSI
Synchronize
Prescaler
1, 2, 4, 8
0
2
T1OSCEN(1)
T1CKPS<1:0>
T1SYNC
0
Detect
Sleep Input
TMR1CS
Timer1
On/Off
TMR1ON
Clear TMR1
(CCP Special Event Trigger)
Set
TMR1IF
on Overflow
TMR1
High Byte
TMR1L
8
Read TMR1L
Write TMR1L
8
8
TMR1H
8
8
Internal Data Bus
Note 1: When enable bit, T1OSCEN, is cleared, the inverter and feedback resistor are turned off to eliminate power drain.
12.2
Timer1 16-Bit Read/Write Mode
Timer1 can be configured for 16-bit reads and writes
(see Figure 12-2). When the RD16 control bit
(T1CON<7>) is set, the address for TMR1H is mapped
to a buffer register for the high byte of Timer1. A read
from TMR1L will load the contents of the high byte of
Timer1 into the Timer1 High Byte Buffer register. This
provides the user with the ability to accurately read all
16 bits of Timer1 without having to determine whether a
read of the high byte, followed by a read of the low byte,
has become invalid due to a rollover between reads.
A write to the high byte of Timer1 must also take place
through the TMR1H Buffer register. The Timer1 high
byte is updated with the contents of TMR1H when a
write occurs to TMR1L. This allows a user to write all
16 bits to both the high and low bytes of Timer1 at once.
12.3
Timer1 Oscillator
An on-chip crystal oscillator circuit is incorporated
between pins T1OSI (input) and T1OSO (amplifier
output). It is enabled by setting the Timer1 Oscillator
Enable bit, T1OSCEN (T1CON<3>). The oscillator is a
low-power circuit rated for 32 kHz crystals. It will continue
to run during all power-managed modes. The circuit for a
typical oscillator is shown in Figure 12-3. Table 12-1
shows the capacitor selection for the Timer1 oscillator.
The user must provide a software time delay to ensure
proper start-up of the Timer1 oscillator.
FIGURE 12-3:
EXTERNAL
COMPONENTS FOR THE
TIMER1 OSCILLATOR
C1
27 pF
The high byte of Timer1 is not directly readable or
writable in this mode. All reads and writes must take
place through the Timer1 High Byte Buffer register.
Writes to TMR1H do not clear the Timer1 prescaler.
The prescaler is only cleared on writes to TMR1L.
PIC18F45J10
T1OSI
XTAL
32.768 kHz
T1OSO
C2
27 pF
Note:
© 2009 Microchip Technology Inc.
See the Notes with Table 12-1 for additional
information about capacitor selection.
DS39682E-page 121
PIC18F45J10 FAMILY
TABLE 12-1:
CAPACITOR SELECTION FOR
THE TIMER OSCILLATOR(2,3,4)
Oscillator
Type
Freq.
C1
C2
LP
32 kHz
27 pF(1)
27 pF(1)
Note 1: Microchip suggests these values as a
starting point in validating the oscillator
circuit.
2: Higher capacitance increases the stability
of the oscillator but also increases the
start-up time.
3: Since each resonator/crystal has its own
characteristics, the user should consult
the resonator/crystal manufacturer for
appropriate
values
of
external
components.
4: Capacitor values are for design guidance
only.
12.3.1
12.3.2
TIMER1 OSCILLATOR LAYOUT
CONSIDERATIONS
The Timer1 oscillator circuit draws very little power
during operation. Due to the low-power nature of the
oscillator, it may also be sensitive to rapidly changing
signals in close proximity.
The oscillator circuit, shown in Figure 12-3, should be
located as close as possible to the microcontroller.
There should be no circuits passing within the oscillator
circuit boundaries other than VSS or VDD.
If a high-speed circuit must be located near the oscillator (such as the CCP1 pin in Output Compare or PWM
mode, or the primary oscillator using the OSC2 pin), a
grounded guard ring around the oscillator circuit, as
shown in Figure 12-4, may be helpful when used on a
single-sided PCB or in addition to a ground plane.
FIGURE 12-4:
OSCILLATOR CIRCUIT
WITH GROUNDED
GUARD RING
USING TIMER1 AS A
CLOCK SOURCE
VDD
VSS
The Timer1 oscillator is also available as a clock source
in power-managed modes. By setting the clock select
bits, SCS<1:0> (OSCCON<1:0>), to ‘01’, the device
switches to SEC_RUN mode; both the CPU and
peripherals are clocked from the Timer1 oscillator. If the
IDLEN bit (OSCCON<7>) is cleared and a SLEEP
instruction is executed, the device enters SEC_IDLE
mode. Additional details are available in Section 4.0
“Power-Managed Modes”.
Whenever the Timer1 oscillator is providing the clock
source, the Timer1 system clock status flag, T1RUN
(T1CON<6>), is set. This can be used to determine the
controller’s current clocking mode. It can also indicate
the clock source being currently used by the Fail-Safe
Clock Monitor. If the Clock Monitor is enabled and the
Timer1 oscillator fails while providing the clock, polling
the T1RUN bit will indicate whether the clock is being
provided by the Timer1 oscillator or another source.
DS39682E-page 122
OSC1
OSC2
RC0
RC1
RC2
Note: Not drawn to scale.
12.4
Timer1 Interrupt
The TMR1 register pair (TMR1H:TMR1L) increments
from 0000h to FFFFh and rolls over to 0000h. The
Timer1 interrupt, if enabled, is generated on overflow
which is latched in interrupt flag bit, TMR1IF
(PIR1<0>). This interrupt can be enabled or disabled
by setting or clearing the Timer1 Interrupt Enable bit,
TMR1IE (PIE1<0>).
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
12.5
Resetting Timer1 Using the
ECCP/CCP Special Event Trigger
If ECCP1/CCP1 or CCP2 is configured to generate
a Special Event Trigger in Compare mode
(CCPxM<3:0> = 1011), this signal will reset Timer1.
The trigger from CCP2 will also start an A/D conversion
if the A/D module is enabled (see Section 15.2.1
“Special Event Trigger” for more information).
The module must be configured as either a timer or a
synchronous counter to take advantage of this feature.
When used this way, the CCPRH:CCPRL register pair
effectively becomes a period register for Timer1.
If Timer1 is running in Asynchronous Counter mode,
this Reset operation may not work.
In the event that a write to Timer1 coincides with a
Special Event Trigger, the write operation will take
precedence.
Note:
The Special Event Triggers from the
ECCP1/CCPx module will not set the
TMR1IF interrupt flag bit (PIR1<0>).
12.6
Using Timer1 as a Real-Time Clock
Adding an external LP oscillator to Timer1 (such as the
one described in Section 12.3 “Timer1 Oscillator”
above) gives users the option to include RTC functionality to their applications. This is accomplished with an
inexpensive watch crystal to provide an accurate time
base and several lines of application code to calculate
the time. When operating in Sleep mode and using a
battery or supercapacitor as a power source, it can
completely eliminate the need for a separate RTC
device and battery backup.
The application code routine, RTCisr, shown in
Example 12-1, demonstrates a simple method to
increment a counter at one-second intervals using an
Interrupt Service Routine. Incrementing the TMR1
register pair to overflow triggers the interrupt and calls
the routine which increments the seconds counter by
one. Additional counters for minutes and hours are
incremented as the previous counter overflows.
Since the register pair is 16 bits wide, counting up to
overflow the register directly from a 32.768 kHz clock
would take 2 seconds. To force the overflow at the
required one-second intervals, it is necessary to
preload it. The simplest method is to set the MSb of
TMR1H with a BSF instruction. Note that the TMR1L
register is never preloaded or altered; doing so may
introduce cumulative error over many cycles.
For this method to be accurate, Timer1 must operate in
Asynchronous mode and the Timer1 overflow interrupt
must be enabled (PIE1<0> = 1) as shown in the
routine, RTCinit. The Timer1 oscillator must also be
enabled and running at all times.
© 2009 Microchip Technology Inc.
DS39682E-page 123
PIC18F45J10 FAMILY
EXAMPLE 12-1:
IMPLEMENTING A REAL-TIME CLOCK USING A TIMER1 INTERRUPT SERVICE
RTCinit
MOVLW
MOVWF
CLRF
MOVLW
MOVWF
CLRF
CLRF
MOVLW
MOVWF
BSF
RETURN
80h
TMR1H
TMR1L
b’00001111’
T1CON
secs
mins
.12
hours
PIE1, TMR1IE
BSF
BCF
INCF
MOVLW
CPFSGT
RETURN
CLRF
INCF
MOVLW
CPFSGT
RETURN
CLRF
INCF
MOVLW
CPFSGT
RETURN
CLRF
RETURN
TMR1H, 7
PIR1, TMR1IF
secs, F
.59
secs
; Preload TMR1 register pair
; for 1 second overflow
; Configure for external clock,
; Asynchronous operation, external oscillator
; Initialize timekeeping registers
;
; Enable Timer1 interrupt
RTCisr
TABLE 12-2:
Name
secs
mins, F
.59
mins
mins
hours, F
.23
hours
;
;
;
;
Preload for 1 sec overflow
Clear interrupt flag
Increment seconds
60 seconds elapsed?
;
;
;
;
No, done
Clear seconds
Increment minutes
60 minutes elapsed?
;
;
;
;
No, done
clear minutes
Increment hours
24 hours elapsed?
; No, done
; Reset hours
; Done
hours
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
TMR1L
Timer1 Register Low Byte
48
TMR1H
Timer1 Register High Byte
48
T1CON
RD16
T1RUN
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC
TMR1CS
TMR1ON
48
Legend: Shaded cells are not used by the Timer1 module.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 124
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
13.0
TIMER2 MODULE
13.1
The Timer2 timer module incorporates the following
features:
• 8-bit Timer and Period registers (TMR2 and PR2,
respectively)
• Readable and writable (both registers)
• Software programmable prescaler
(1:1, 1:4 and 1:16)
• Software programmable postscaler
(1:1 through 1:16)
• Interrupt on TMR2 to PR2 match
• Optional use as the shift clock for the
MSSP module
The module is controlled through the T2CON register
(Register 13-1) which enables or disables the timer and
configures the prescaler and postscaler. Timer2 can be
shut off by clearing control bit, TMR2ON (T2CON<2>),
to minimize power consumption.
A simplified block diagram of the module is shown in
Figure 13-1.
Timer2 Operation
In normal operation, TMR2 is incremented from 00h on
each clock (FOSC/4). A 4-bit counter/prescaler on the
clock input gives direct input, divide-by-4 and divide-by-16
prescale options; these are selected by the prescaler control bits, T2CKPS<1:>0 (T2CON<1:0>). The value of
TMR2 is compared to that of the Period register, PR2, on
each clock cycle. When the two values match, the
comparator generates a match signal as the timer output.
This signal also resets the value of TMR2 to 00h on the
next cycle and drives the output counter/postscaler (see
Section 13.2 “Timer2 Interrupt”).
The TMR2 and PR2 registers are both directly readable
and writable. The TMR2 register is cleared on any
device Reset, while the PR2 register initializes at FFh.
Both the prescaler and postscaler counters are cleared
on the following events:
• a write to the TMR2 register
• a write to the T2CON register
• any device Reset (Power-on Reset, MCLR Reset,
Watchdog Timer Reset or Brown-out Reset)
TMR2 is not cleared when T2CON is written.
REGISTER 13-1:
T2CON: TIMER2 CONTROL REGISTER
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
T2OUTPS3
T2OUTPS2
T2OUTPS1
T2OUTPS0
TMR2ON
T2CKPS1
T2CKPS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
Unimplemented: Read as ‘0’
bit 6-3
T2OUTPS<3:0>: Timer2 Output Postscale Select bits
0000 = 1:1 Postscale
0001 = 1:2 Postscale
•
•
•
1111 = 1:16 Postscale
bit 2
TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0
T2CKPS<1:0>: Timer2 Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS39682E-page 125
PIC18F45J10 FAMILY
13.2
Timer2 Interrupt
13.3
Timer2 can also generate an optional device interrupt.
The Timer2 output signal (TMR2 to PR2 match) provides the input for the 4-bit output counter/postscaler.
This counter generates the TMR2 match interrupt flag
which is latched in TMR2IF (PIR1<1>). The interrupt is
enabled by setting the TMR2 Match Interrupt Enable
bit, TMR2IE (PIE1<1>).
Timer2 Output
The unscaled output of TMR2 is available primarily to
the CCP modules, where it is used as a time base for
operations in PWM mode.
Timer2 can be optionally used as the shift clock source
for the MSSP module operating in SPI mode.
Additional information is provided in Section 16.0
“Master Synchronous Serial Port (MSSP) Module”.
A range of 16 postscale options (from 1:1 through 1:16
inclusive) can be selected with the postscaler control
bits, T2OUTPS<3:0> (T2CON<6:3>).
FIGURE 13-1:
TIMER2 BLOCK DIAGRAM
4
T2OUTPS<3:0>
1:1 to 1:16
Postscaler
2
T2CKPS<1:0>
TMR2
Comparator
8
PR2
8
8
Internal Data Bus
Name
TMR2 Output
(to PWM or MSSP)
TMR2/PR2
Match
Reset
1:1, 1:4, 1:16
Prescaler
FOSC/4
TABLE 13-1:
Set TMR2IF
REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Bit 7
Bit 6
INTCON GIE/GIEH PEIE/GIEL
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
47
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
TMR2
T2CON
PR2
Timer2 Register
—
T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON
48
T2CKPS1 T2CKPS0
Timer2 Period Register
48
48
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer2 module.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 126
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
14.0
The Capture and Compare operations described in this
chapter apply to all standard and Enhanced CCP
modules.
CAPTURE/COMPARE/PWM
(CCP) MODULES
PIC18F45J10 family devices all have two CCP
(Capture/Compare/PWM) modules. Each module
contains a 16-bit register which can operate as a 16-bit
Capture register, a 16-bit Compare register or a PWM
Master/Slave Duty Cycle register.
In 28-pin devices, the two standard CCP modules
(CCP1 and CCP2) operate as described in this chapter.
In 40/44-pin devices, CCP1 is implemented as an
Enhanced CCP module (ECCP1) with standard Capture
and Compare modes and Enhanced PWM modes. The
Enhanced CCP implementation is discussed in
Section 15.0 “Enhanced Capture/Compare/PWM
(ECCP) Module”.
REGISTER 14-1:
Note: Throughout this section and Section 15.0
“Enhanced Capture/Compare/PWM (ECCP)
Module”, references to the register and bit
names for CCP modules are referred to generically by the use of ‘x’ or ‘y’ in place of the
specific module number. Thus, “CCPxCON”
might refer to the control register for CCP1,
CCP2 or ECCP1. “CCPxCON” is used
throughout these sections to refer to the
module control register regardless of whether
the CCP module is a standard or Enhanced
implementation.
CCPxCON: CCP1/CCP2 CONTROL REGISTER IN 28-PIN DEVICES
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
DCxB1
DCxB0
CCPxM3
CCPxM2
CCPxM1
CCPxM0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
Unimplemented: Read as ‘0’
bit 5-4
DCxB<1:0>: PWM Duty Cycle bit 1 and bit 0
Capture mode:
Unused.
Compare mode:
Unused.
PWM mode:
These bits are the two LSbs (bit 1 and bit 0) of the 10-bit PWM duty cycle. The eight MSbs (DCxB<9:2>)
of the duty cycle are found in CCPRxL.
bit 3-0
CCPxM<3:0>: CCPx Mode Select bits
0000 = Capture/Compare/PWM disabled (resets CCPx module)
0001 = Reserved
0010 = Compare mode, toggle output on match (CCPxIF bit is set)
0011 = Reserved
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode: initialize CCPx pin low; on compare match, force CCPx pin high
(CCPxIF bit is set)
1001 = Compare mode: initialize CCPx pin high; on compare match, force CCPx pin low
(CCPxIF bit is set)
1010 = Compare mode: generate software interrupt on compare match (CCPxIF bit is set,
CCPx pin reflects I/O state)
1011 = Compare mode: trigger special event, reset timer, start A/D conversion on
CCPx match (CCPxIF bit is set)
11xx = PWM mode
© 2009 Microchip Technology Inc.
DS39682E-page 127
PIC18F45J10 FAMILY
14.1
CCP Module Configuration
Each Capture/Compare/PWM module is associated
with a control register (generically, CCPxCON) and a
data register (CCPRx). The data register, in turn, is
comprised of two 8-bit registers: CCPRxL (low byte)
and CCPRxH (high byte). All registers are both
readable and writable.
14.1.1
CCP MODULES AND TIMER
RESOURCES
The CCP modules utilize Timers 1 or 2, depending on
the mode selected. Timer1 is available to modules in
Capture or Compare modes, while Timer2 is available
for modules in PWM mode.
TABLE 14-1:
ECCP/CCP MODE – TIMER
RESOURCE
ECCP/CCP Mode
Timer Resource
Capture
Compare
PWM
Timer1
Timer1
Timer2
TABLE 14-2:
Both modules may be active at any given time and may
share the same timer resource if they are configured to
operate in the same mode (Capture/Compare or PWM)
at the same time. The interactions between the two
modules are summarized in Figure 14-1 and
Figure 14-2. In Timer1 in Asynchronous Counter mode,
the capture operation will not work.
14.1.2
CCP2 PIN ASSIGNMENT
The pin assignment for CCP2 (Capture input, Compare
and PWM output) can change, based on device configuration. The CCP2MX Configuration bit determines
which pin CCP2 is multiplexed to. By default, it is
assigned to RC1 (CCP2MX = 1). If the Configuration bit
is cleared, CCP2 is multiplexed with RB3.
Changing the pin assignment of CCP2 does not automatically change any requirements for configuring the
port pin. Users must always verify that the appropriate
TRIS register is configured correctly for CCP2
operation regardless of where it is located.
INTERACTIONS BETWEEN ECCP1/CCP1 AND CCP2 FOR TIMER RESOURCES
CCP1 Mode CCP2 Mode
Interaction
Capture
Capture
Each module uses TMR1 as the time base.
Capture
Compare
CCP2 can be configured for the Special Event Trigger to reset TMR1. Automatic A/D
conversions on the trigger event can also be done. Operation of ECCP1/CCP1 will be
affected.
Compare
Capture
ECCP1/CCP1 can be configured for the Special Event Trigger to reset TMR1. Operation
of CCP2 will be affected.
Compare
Compare
Either module can be configured for the Special Event Trigger to reset TMR1. Automatic
A/D conversions on the CCP2 trigger event can be done.
Capture
PWM(1)
None
(1)
None
Capture
None
Compare
None
Compare
PWM(1)
(1)
PWM
PWM(1)
Note 1:
PWM
PWM
Both PWMs will have the same frequency and update rate (TMR2 interrupt).
Includes standard and Enhanced PWM operation.
DS39682E-page 128
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
14.2
14.2.3
Capture Mode
In Capture mode, the CCPRxH:CCPRxL register pair
captures the 16-bit value of the TMR1 register when an
event occurs on the corresponding CCPx pin. An event
is defined as one of the following:
•
•
•
•
every falling edge
every rising edge
every 4th rising edge
every 16th rising edge
The event is selected by the mode select bits,
CCPxM<3:0> (CCPxCON<3:0>). When a capture is
made, the interrupt request flag bit, CCPxIF, is set; it
must be cleared in software. If another capture occurs
before the value in register CCPRx is read, the old
captured value is overwritten by the new captured value.
14.2.1
14.2.2
There are four prescaler settings in Capture mode; they
are specified as part of the operating mode selected by
the mode select bits (CCPxM<3:0>). Whenever the
CCP module is turned off or Capture mode is disabled,
the prescaler counter is cleared. This means that any
Reset will clear the prescaler counter.
Switching from one capture prescaler to another may
generate an interrupt. Also, the prescaler counter will
not be cleared; therefore, the first capture may be from
a non-zero prescaler. Example 14-1 shows the
recommended method for switching between capture
prescalers. This example also clears the prescaler
counter and will not generate the “false” interrupt.
EXAMPLE 14-1:
CCP PIN CONFIGURATION
In Capture mode, the appropriate CCPx pin should be
configured as an input by setting the corresponding
TRIS direction bit.
Note:
CCP PRESCALER
If RB3/CCP2 or RC1/CCP2 is configured
as an output, a write to the port can cause
a capture condition.
CLRF
MOVLW
CCP2CON
NEW_CAPT_PS
MOVWF
CCP2CON
CHANGING BETWEEN
CAPTURE PRESCALERS
(CCP2 SHOWN)
;
;
;
;
;
;
Turn CCP module off
Load WREG with the
new prescaler mode
value and CCP ON
Load CCP2CON with
this value
SOFTWARE INTERRUPT
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep the
CCPxIE interrupt enable bit clear to avoid false interrupts. The interrupt flag bit, CCPxIF, should also be
cleared following any such change in operating mode.
FIGURE 14-1:
CAPTURE MODE OPERATION BLOCK DIAGRAM
Set CCP1IF
CCP1 pin
Prescaler
÷ 1, 4, 16
CCP1CON<3:0>
Q1:Q4
CCP2CON<3:0>
© 2009 Microchip Technology Inc.
CCPR1L
TMR1H
TMR1L
CCPR2H
CCPR2L
TMR1H
TMR1L
and
Edge Detect
4
4
Set CCP2IF
4
CCP2 pin
Prescaler
÷ 1, 4, 16
CCPR1H
and
Edge Detect
DS39682E-page 129
PIC18F45J10 FAMILY
14.3
14.3.2
Compare Mode
Timer1 must be running in Timer mode or Synchronized Counter mode if the CCP module is using the
compare feature. In Asynchronous Counter mode, the
compare operation may not work.
In Compare mode, the 16-bit CCPRx register value is
constantly compared against the TMR1 register value.
When a match occurs, the CCPx pin can be:
•
•
•
•
driven high
driven low
toggled (high-to-low or low-to-high)
remain unchanged (that is, reflects the state of the
I/O latch)
14.3.3
14.3.4
SPECIAL EVENT TRIGGER
Both CCP modules are equipped with a Special Event
Trigger. This is an internal hardware signal generated
in Compare mode to trigger actions by other modules.
The Special Event Trigger is enabled by selecting
the Compare Special Event Trigger mode
(CCPxM<3:0> = 1011).
CCP PIN CONFIGURATION
The user must configure the CCPx pin as an output by
clearing the appropriate TRIS bit.
Note:
SOFTWARE INTERRUPT MODE
When the Generate Software Interrupt mode is chosen
(CCPxM<3:0> = 1010), the corresponding CCPx pin is
not affected. Only a CCP interrupt is generated, if
enabled and the CCPxIE bit is set.
The action on the pin is based on the value of the mode
select bits (CCPxM<3:0>). At the same time, the interrupt flag bit, CCPxIF, is set.
14.3.1
TIMER1 MODE SELECTION
Clearing the CCP2CON register will force
the RB3 or RC1 compare output latch
(depending on device configuration) to the
default low level. This is not the PORTB or
PORTC I/O data latch.
For either CCP module, the Special Event Trigger resets
the Timer register pair for whichever timer resource is
currently assigned as the module’s time base. This
allows the CCPRx registers to serve as a Programmable
Period register for either timer.
The Special Event Trigger for CCP2 can also start an
A/D conversion. In order to do this, the A/D converter
must already be enabled.
FIGURE 14-2:
COMPARE MODE OPERATION BLOCK DIAGRAM
CCPR1H
Special Event Trigger
(Timer1 Reset)
Set CCP1IF
CCPR1L
CCP1 pin
Output
Logic
Compare
Match
Comparator
S
Q
R
TRIS
Output Enable
4
CCP1CON<3:0>
TMR1H
TMR1L
Special Event Trigger
(Timer1 Reset, A/D Trigger)
Set CCP2IF
Comparator
CCPR2H
CCPR2L
Compare
Match
CCP2 pin
Output
Logic
4
S
Q
R
TRIS
Output Enable
CCP2CON<3:0>
DS39682E-page 130
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 14-3:
Name
INTCON
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE AND TIMER1
Bit 7
Bit 6
Bit 5
GIE/GIEH PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
IPEN
—
CM
RI
TO
PD
POR
BOR
46
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
(1)
PSPIE
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
RCON
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
IPR2
TRISB
49
PORTB Data Direction Control Register
50
TRISC
PORTC Data Direction Control Register
50
TMR1L
Timer1 Register Low Byte
48
TMR1H
Timer1 Register High Byte
T1CON
RD16
T1RUN
48
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC
CCPR1L
Capture/Compare/PWM Register 1 Low Byte
CCPR1H
Capture/Compare/PWM Register 1 High Byte
CCP1CON
P1M1(1)
P1M0(1)
DC1B1
DC1B0
TMR1CS TMR1ON
48
49
49
CCP1M3
CCP1M2
CCP1M1
CCP1M0
49
CCPR2L
Capture/Compare/PWM Register 2 Low Byte
49
CCPR2H
Capture/Compare/PWM Register 2 High Byte
49
CCP2CON
—
—
DC2B1
DC2B0
CCP2M3
CCP2M2
CCP2M1
CCP2M0
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Capture/Compare or Timer1.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 131
PIC18F45J10 FAMILY
14.4
14.4.1
PWM Mode
In Pulse-Width Modulation (PWM) mode, the CCPx pin
produces up to a 10-bit resolution PWM output. Since
the CCP2 pin is multiplexed with a PORTB or PORTC
data latch, the appropriate TRIS bit must be cleared to
make the CCP2 pin an output.
Note:
Clearing the CCP2CON register will force
the RB3 or RC1 output latch (depending on
device configuration) to the default low
level. This is not the PORTB or PORTC I/O
data latch.
Figure 14-3 shows a simplified block diagram of the
CCP module in PWM mode.
For a step-by-step procedure on how to set up the CCP
module for PWM operation, see Section 14.4.4
“Setup for PWM Operation”.
FIGURE 14-3:
SIMPLIFIED PWM BLOCK
DIAGRAM
The PWM period is specified by writing to the PR2
register. The PWM period can be calculated using the
following formula:
EQUATION 14-1:
PWM Period = [(PR2) + 1] • 4 • TOSC •
(TMR2 Prescale Value)
PWM frequency is defined as 1/[PWM period].
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
• TMR2 is cleared
• The CCPx pin is set (exception: if PWM duty
cycle = 0%, the CCPx pin will not be set)
• The PWM duty cycle is latched from CCPRxL into
CCPRxH
Note:
CCPxCON<5:4>
Duty Cycle Registers
CCPRxL
14.4.2
CCPRxH (Slave)
CCPx Output
R
Comparator
TMR2
(Note 1)
Comparator
S
Clear Timer,
CCP1 pin and
latch D.C.
PR2
Q
Corresponding
TRIS bit
Note 1: The 8-bit TMR2 value is concatenated with the 2-bit
internal Q clock, or 2 bits of the prescaler, to create the
10-bit time base.
A PWM output (Figure 14-4) has a time base (period)
and a time that the output stays high (duty cycle).
The frequency of the PWM is the inverse of the
period (1/period).
FIGURE 14-4:
PWM PERIOD
The Timer2 postscalers (see Section 13.0
“Timer2 Module”) are not used in the
determination of the PWM frequency. The
postscaler could be used to have a servo
update rate at a different frequency than
the PWM output.
PWM DUTY CYCLE
The PWM duty cycle is specified by writing to the
CCPRxL register and to the CCPxCON<5:4> bits. Up
to 10-bit resolution is available. The CCPRxL contains
the eight MSbs and the CCPxCON<5:4> contains the
two LSbs. This 10-bit value is represented by
CCPRxL:CCPxCON<5:4>. The following equation is
used to calculate the PWM duty cycle in time:
EQUATION 14-2:
PWM Duty Cycle = (CCPRXL:CCPXCON<5:4>) •
TOSC • (TMR2 Prescale Value)
CCPRxL and CCPxCON<5:4> can be written to at any
time, but the duty cycle value is not latched into
CCPRxH until after a match between PR2 and TMR2
occurs (i.e., the period is complete). In PWM mode,
CCPRxH is a read-only register.
PWM OUTPUT
Period
Duty Cycle
TMR2 = PR2
TMR2 = Duty Cycle
TMR2 = PR2
DS39682E-page 132
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
The CCPRxH register and a 2-bit internal latch are
used to double-buffer the PWM duty cycle. This
double-buffering is essential for glitchless PWM
operation.
EQUATION 14-3:
F OSC
log ⎛ ---------------⎞
⎝ F PWM⎠
PWM Resolution (max) = -----------------------------bits
log ( 2 )
When the CCPRxH and 2-bit latch match TMR2,
concatenated with an internal 2-bit Q clock or 2 bits of
the TMR2 prescaler, the CCPx pin is cleared.
Note:
The maximum PWM resolution (bits) for a given PWM
frequency is given by the equation:
TABLE 14-4:
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
PWM Frequency
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
14.4.3
If the PWM duty cycle value is longer than
the PWM period, the CCP2 pin will not be
cleared.
2.44 kHz
9.77 kHz
39.06 kHz
156.25 kHz
312.50 kHz
416.67 kHz
16
4
1
1
1
1
FFh
FFh
FFh
3Fh
1Fh
17h
10
10
10
8
7
6.58
PWM AUTO-SHUTDOWN
(CCP1 ONLY)
The PWM auto-shutdown features of the Enhanced CCP
module are also available to CCP1 in 28-pin devices. The
operation of this feature is discussed in detail in
Section 15.4.7 “Enhanced PWM Auto-Shutdown”.
14.4.4
The following steps should be taken when configuring
the CCP module for PWM operation:
1.
2.
Auto-shutdown features are not available for CCP2.
3.
4.
5.
© 2009 Microchip Technology Inc.
SETUP FOR PWM OPERATION
Set the PWM period by writing to the PR2
register.
Set the PWM duty cycle by writing to the
CCPRxL register and CCPxCON<5:4> bits.
Make the CCPx pin an output by clearing the
appropriate TRIS bit.
Set the TMR2 prescale value, then enable
Timer2 by writing to T2CON.
Configure the CCPx module for PWM operation.
DS39682E-page 133
PIC18F45J10 FAMILY
TABLE 14-5:
Name
INTCON
REGISTERS ASSOCIATED WITH PWM AND TIMER2
Bit 7
Bit 6
GIE/GIEH PEIE/GIEL
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
IPEN
—
CM
RI
TO
PD
POR
BOR
46
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE
(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
RCON
TRISB
PORTB Data Direction Control Register
50
TRISC
PORTC Data Direction Control Register
50
TMR2
Timer2 Register
48
PR2
Timer2 Period Register
48
T2CON
—
T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
CCPR1L
Capture/Compare/PWM Register 1 Low Byte
CCPR1H
Capture/Compare/PWM Register 1 High Byte
CCP1CON
P1M1(1)
P1M0(1)
DC1B1
DC1B0
48
49
49
CCP1M3
CCP1M2
CCP1M1
CCP1M0
49
CCPR2L
Capture/Compare/PWM Register 2 Low Byte
49
CCPR2H
Capture/Compare/PWM Register 2 High Byte
49
CCP2CON
ECCP1AS
ECCP1DEL
—
—
ECCPASE ECCPAS2
PRSEN
PDC6(1)
DC2B1
DC2B0
CCP2M3
CCP2M2
ECCPAS1
ECCPAS0
PSSAC1
PSSAC0 PSSBD1(1) PSSBD0(1)
CCP2M1
49
PDC5(1)
PDC4(1)
PDC3(1)
PDC2(1)
49
PDC1(1)
CCP2M0
PDC0(1)
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PWM or Timer2.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 134
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
15.0
ENHANCED CAPTURE/
COMPARE/PWM (ECCP)
MODULE
Note:
The ECCP module is implemented only in
40/44-pin devices.
In
PIC18F44J10/45J10
devices,
ECCP1
is
implemented as a standard CCP module with
Enhanced PWM capabilities. These include the
provisions for 2 or 4 output channels, user-selectable
polarity, dead-band control and automatic shutdown
REGISTER 15-1:
and restart. The Enhanced features are discussed in
detail in Section 15.4 “Enhanced PWM Mode”.
Capture, Compare and single output PWM functions of
the ECCP module are the same as described for the
standard CCP module.
The control register for the Enhanced CCP module is
shown in Register 15-1. It differs from the CCP1CON
register in PIC18F24J10/25J10 devices in that the two
Most Significant bits are implemented to control PWM
functionality.
CCP1CON: ECCP1 CONTROL REGISTER (40/44-PIN DEVICES)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
P1M1
P1M0
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
P1M<1:0>: Enhanced PWM Output Configuration bits
If CCP1M<3:2> = 00, 01, 10:
xx = P1A assigned as Capture/Compare input/output; P1B, P1C, P1D assigned as port pins
If CCP1M<3:2> = 11:
00 = Single output: P1A modulated; P1B, P1C, P1D assigned as port pins
01 = Full-bridge output forward: P1D modulated; P1A active; P1B, P1C inactive
10 = Half-bridge output: P1A, P1B modulated with dead-band control; P1C, P1D assigned as port pins
11 = Full-bridge output reverse: P1B modulated; P1C active; P1A, P1D inactive
bit 5-4
DC1B<1:0>: PWM Duty Cycle bit 1 and bit 0
Capture mode:
Unused.
Compare mode:
Unused.
PWM mode:
These bits are the two LSbs of the 10-bit PWM duty cycle. The eight MSbs of the duty cycle are found
in CCPR1L.
bit 3-0
CCP1M<3:0>: CCP1 Module Mode Select bits
0000 = Capture/Compare/PWM off (resets ECCP module)
0001 = Reserved
0010 = Compare mode, toggle output on match
0011 = Capture mode
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode, initialize CCP1 pin low, set output on compare match (set CCP1IF)
1001 = Compare mode, initialize CCP1 pin high, clear output on compare match (set CCP1IF)
1010 = Compare mode, generate software interrupt only, CCP1 pin reverts to I/O state
1011 = Compare mode, trigger special event (ECCP resets TMR1, sets CCP1IF bit)
1100 = PWM mode; P1A, P1C active-high; P1B, P1D active-high
1101 = PWM mode; P1A, P1C active-high; P1B, P1D active-low
1110 = PWM mode; P1A, P1C active-low; P1B, P1D active-high
1111 = PWM mode; P1A, P1C active-low; P1B, P1D active-low
© 2009 Microchip Technology Inc.
DS39682E-page 135
PIC18F45J10 FAMILY
In addition to the expanded range of modes available
through the CCP1CON register and ECCP1AS
register, the ECCP module has an additional register
associated with Enhanced PWM operation and
auto-shutdown features. It is:
• ECCP1DEL (PWM Dead-Band Delay)
15.1
ECCP Outputs and Configuration
The Enhanced CCP module may have up to four PWM
outputs, depending on the selected operating mode.
These outputs, designated P1A through P1D, are
multiplexed with I/O pins on PORTC and PORTD. The
outputs that are active depend on the ECCP operating
mode selected. The pin assignments are summarized
in Table 15-1.
To configure the I/O pins as PWM outputs, the proper
PWM mode must be selected by setting the P1M<1:0>
and CCP1M<3:0> bits. The appropriate TRISC and
TRISD direction bits for the port pins must also be set
as outputs.
15.1.1
ECCP MODULES AND TIMER
RESOURCES
15.2
Except for the operation of the Special Event Trigger
discussed below, the Capture and Compare modes of
the ECCP module are identical in operation to that of
CCP2. These are discussed in detail in Section 14.2
“Capture Mode” and Section 14.3 “Compare
Mode”. No changes are required when moving
between 28-pin and 40/44-pin devices.
15.2.1
SPECIAL EVENT TRIGGER
The Special Event Trigger output of ECCP1 resets the
TMR1 register pair. This allows the CCPR1 register to
effectively be a 16-bit programmable period register for
Timer1.
15.3
Standard PWM Mode
When configured in Single Output mode, the ECCP
module functions identically to the standard CCP
module in PWM mode, as described in Section 14.4
“PWM Mode”. This is also sometimes referred to as
“Compatible CCP” mode, as in Table 15-1.
Note:
Like the standard CCP modules, the ECCP module can
utilize Timers 1 or 2, depending on the mode selected.
Timer1 is available for modules in Capture or Compare
modes, while Timer2 is available for modules in PWM
mode. Interactions between the standard and
Enhanced CCP modules are identical to those
described for standard CCP modules. Additional
details on timer resources are provided in
Section 14.1.1
“CCP
Modules
and
Timer
Resources”.
TABLE 15-1:
Capture and Compare Modes
When setting up single output PWM
operations, users are free to use either of
the processes described in Section 14.4.4
“Setup for PWM Operation” or
Section 15.4.9 “Setup for PWM Operation”. The latter is more generic and will
work for either single or multi-output PWM.
PIN ASSIGNMENTS FOR VARIOUS ECCP1 MODES
ECCP Mode
CCP1CON
Configuration
RC2
RD5
RD6
RD7
All 40/44-pin Devices:
Compatible CCP
00xx 11xx
CCP1
RD5/PSP5
RD6/PSP6
RD7/PSP7
Dual PWM
10xx 11xx
P1A
P1B
RD6/PSP6
RD7/PSP7
Quad PWM
x1xx 11xx
P1A
P1B
P1C
P1D
Legend: x = Don’t care. Shaded cells indicate pin assignments not used by ECCP1 in a given mode.
DS39682E-page 136
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
15.4
15.4.1
Enhanced PWM Mode
The Enhanced PWM mode provides additional PWM
output options for a broader range of control applications. The module is a backward compatible version of
the standard CCP module and offers up to four outputs,
designated P1A through P1D. Users are also able to
select the polarity of the signal (either active-high or
active-low). The module’s output mode and polarity are
configured by setting the P1M<1:0> and CCP1M<3:0>
bits of the CCP1CON register.
Figure 15-1 shows a simplified block diagram of PWM
operation. All control registers are double-buffered and
are loaded at the beginning of a new PWM cycle (the
period boundary when Timer2 resets) in order to
prevent glitches on any of the outputs. The exception is
the PWM Dead-Band Delay register, ECCP1DEL,
which is loaded at either the duty cycle boundary or the
period boundary (whichever comes first). Because of
the buffering, the module waits until the assigned timer
resets instead of starting immediately. This means that
Enhanced PWM waveforms do not exactly match the
standard PWM waveforms, but are instead offset by
one full instruction cycle (4 TOSC).
PWM PERIOD
The PWM period is specified by writing to the PR2
register. The PWM period can be calculated using the
following equation.
EQUATION 15-1:
PWM Period =
PWM frequency is defined as 1/[PWM period]. When
TMR2 is equal to PR2, the following three events occur
on the next increment cycle:
• TMR2 is cleared
• The CCP1 pin is set (if PWM duty cycle = 0%, the
CCP1 pin will not be set)
• The PWM duty cycle is copied from CCPR1L into
CCPR1H
Note:
As before, the user must manually configure the
appropriate TRIS bits for output.
FIGURE 15-1:
[(PR2) + 1] • 4 • TOSC •
(TMR2 Prescale Value)
The Timer2 postscaler (see Section 13.0
“Timer2 Module”) is not used in the
determination of the PWM frequency. The
postscaler could be used to have a servo
update rate at a different frequency than
the PWM output.
SIMPLIFIED BLOCK DIAGRAM OF THE ENHANCED PWM MODULE
CCP1CON<5:4>
Duty Cycle Registers
CCP1M<3:0>
4
P1M1<1:0>
2
CCPR1L
CCP1/P1A
CCP1/P1A
TRISx<x>
CCPR1H (Slave)
P1B
R
Comparator
Q
Output
Controller
P1B
TRISx<x>
P1C
TMR2
Comparator
PR2
(Note 1)
P1C
TRISx<x>
S
P1D
Clear Timer,
set CCP1 pin and
latch D.C.
P1D
TRISx<x>
ECCP1DEL
Note: The 8-bit TMR2 register is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler, to create the 10-bit
time base.
© 2009 Microchip Technology Inc.
DS39682E-page 137
PIC18F45J10 FAMILY
15.4.2
PWM DUTY CYCLE
Note:
The PWM duty cycle is specified by writing to the
CCPR1L register and to the CCP1CON<5:4> bits. Up
to 10-bit resolution is available. The CCPR1L register
contains the eight MSbs and the CCP1CON<5:4>
contains the two LSbs. This 10-bit value is represented
by CCPR1L:CCP1CON<5:4>. The PWM duty cycle is
calculated by the following equation:
EQUATION 15-2:
PWM Duty Cycle = (CCPR1L:CCP1CON<5:4>) •
TOSC • (TMR2 Prescale Value)
CCPR1L and CCP1CON<5:4> can be written to at any
time, but the duty cycle value is not copied into
CCPR1H until a match between PR2 and TMR2 occurs
(i.e., the period is complete). In PWM mode, CCPR1H
is a read-only register.
The CCPR1H register and a 2-bit internal latch are
used to double-buffer the PWM duty cycle. This
double-buffering is essential for glitchless PWM operation. When the CCPR1H and 2-bit latch match TMR2,
concatenated with an internal 2-bit Q clock or two bits
of the TMR2 prescaler, the CCP1 pin is cleared. The
maximum PWM resolution (bits) for a given PWM
frequency is given by the following equation:
15.4.3
If the PWM duty cycle value is longer than
the PWM period, the CCP1 pin will not be
cleared.
PWM OUTPUT CONFIGURATIONS
The P1M<1:0> bits in the CCP1CON register allow one
of four configurations:
•
•
•
•
Single Output
Half-Bridge Output
Full-Bridge Output, Forward mode
Full-Bridge Output, Reverse mode
The Single Output mode is the standard PWM mode
discussed in Section 15.4 “Enhanced PWM Mode”.
The Half-Bridge and Full-Bridge Output modes are
covered in detail in the sections that follow.
The general relationship of the outputs in all
configurations is summarized in Figure 15-2.
EQUATION 15-3:
(
log FOSC
FPWM
PWM Resolution (max) =
log(2)
TABLE 15-2:
) bits
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
PWM Frequency
Timer Prescaler (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
DS39682E-page 138
2.44 kHz
9.77 kHz
39.06 kHz
156.25 kHz
312.50 kHz
416.67 kHz
16
4
1
1
1
1
FFh
FFh
FFh
3Fh
1Fh
17h
10
10
10
8
7
6.58
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 15-2:
PWM OUTPUT RELATIONSHIPS (ACTIVE-HIGH STATE)
0
CCP1CON
<7:6>
00
(Single Output)
Duty
Cycle
SIGNAL
PR2 + 1
Period
P1A Modulated
Delay(1)
Delay(1)
P1A Modulated
10
(Half-Bridge)
P1B Modulated
P1A Active
01
(Full-Bridge,
Forward)
P1B Inactive
P1C Inactive
P1D Modulated
P1A Inactive
11
(Full-Bridge,
Reverse)
P1B Modulated
P1C Active
P1D Inactive
FIGURE 15-3:
PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE)
CCP1CON
<7:6>
00
(Single Output)
SIGNAL
0
Duty
Cycle
PR2 + 1
Period
P1A Modulated
P1A Modulated
10
(Half-Bridge)
Delay(1)
Delay(1)
P1B Modulated
P1A Active
01
(Full-Bridge,
Forward)
P1B Inactive
P1C Inactive
P1D Modulated
P1A Inactive
11
(Full-Bridge,
Reverse)
P1B Modulated
P1C Active
P1D Inactive
Relationships:
• Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value)
• Duty Cycle = TOSC * (CCPR1L<7:0>:CCP1CON<5:4>) * (TMR2 Prescale Value)
• Delay = 4 * TOSC * (ECCP1DEL<6:0>)
Note 1: Dead-band delay is programmed using the ECCP1DEL register (see Section 15.4.6 “Programmable
Dead-Band Delay”).
© 2009 Microchip Technology Inc.
DS39682E-page 139
PIC18F45J10 FAMILY
15.4.4
HALF-BRIDGE MODE
FIGURE 15-4:
In the Half-Bridge Output mode, two pins are used as
outputs to drive push-pull loads. The PWM output signal
is output on the P1A pin, while the complementary PWM
output signal is output on the P1B pin (Figure 15-4). This
mode can be used for half-bridge applications, as shown
in Figure 15-5, or for full-bridge applications where four
power switches are being modulated with two PWM
signals.
In Half-Bridge Output mode, the programmable deadband delay can be used to prevent shoot-through
current in half-bridge power devices. The value of bits,
PDC<6:0>, sets the number of instruction cycles before
the output is driven active. If the value is greater than
the duty cycle, the corresponding output remains
inactive during the entire cycle. See Section 15.4.6
“Programmable Dead-Band Delay” for more details
of the dead-band delay operations.
HALF-BRIDGE PWM
OUTPUT
Period
Period
Duty Cycle
P1A(2)
td
td
P1B(2)
(1)
(1)
(1)
td = Dead-Band Delay
Note 1: At this time, the TMR2 register is equal to the
PR2 register.
2: Output signals are shown as active-high.
Since the P1A and P1B outputs are multiplexed with
the PORTC<2> and PORTD<5> data latches, the
TRISC<2> and TRISD<5> bits must be cleared to
configure P1A and P1B as outputs.
FIGURE 15-5:
EXAMPLES OF HALF-BRIDGE OUTPUT MODE APPLICATIONS
Standard Half-Bridge Circuit (“Push-Pull”)
PIC18F4XJ10
V+
FET
Driver
+
V
-
P1A
Load
FET
Driver
+
V
-
P1B
VHalf-Bridge Output Driving a Full-Bridge Circuit
V+
PIC18F4XJ10
FET
Driver
FET
Driver
P1A
FET
Driver
Load
FET
Driver
P1B
V-
DS39682E-page 140
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
15.4.5
FULL-BRIDGE MODE
In Full-Bridge Output mode, four pins are used as
outputs; however, only two outputs are active at a time.
In the Forward mode, pin P1A is continuously active
and pin P1D is modulated. In the Reverse mode, pin
P1C is continuously active and pin P1B is modulated.
These are illustrated in Figure 15-6.
FIGURE 15-6:
P1A, P1B, P1C and P1D outputs are multiplexed with
the PORTC<2> and PORTD<7:5> data latches. The
TRISC<2> and TRISD<7:5> bits must be cleared to
make the P1A, P1B, P1C and P1D pins outputs.
FULL-BRIDGE PWM OUTPUT
Forward Mode
Period
(2)
P1A
Duty Cycle
P1B(2)
P1C(2)
P1D(2)
(1)
(1)
Reverse Mode
Period
Duty Cycle
P1A(2)
P1B(2)
P1C(2)
P1D(2)
(1)
(1)
Note 1: At this time, the TMR2 register is equal to the PR2 register.
Note 2: Output signal is shown as active-high.
© 2009 Microchip Technology Inc.
DS39682E-page 141
PIC18F45J10 FAMILY
FIGURE 15-7:
EXAMPLE OF FULL-BRIDGE APPLICATION
V+
PIC18F4XJ10
FET
Driver
QC
QA
FET
Driver
P1A
Load
P1B
FET
Driver
P1C
FET
Driver
QD
QB
VP1D
15.4.5.1
Direction Change in Full-Bridge Mode
In the Full-Bridge Output mode, the P1M1 bit in the
CCP1CON register allows the user to control the
forward/reverse direction. When the application firmware changes this direction control bit, the module will
assume the new direction on the next PWM cycle.
Just before the end of the current PWM period, the
modulated outputs (P1B and P1D) are placed in their
inactive state, while the unmodulated outputs (P1A and
P1C) are switched to drive in the opposite direction.
This occurs in the time interval, 4 TOSC * (Timer2
Prescale Value), before the next PWM period begins.
The Timer2 prescaler will be either 1, 4 or 16, depending on the value of the T2CKPS<1:0> bits
(T2CON<1:0>). During the interval from the switch of
the unmodulated outputs to the beginning of the next
period, the modulated outputs (P1B and P1D) remain
inactive. This relationship is shown in Figure 15-8.
Note that in the Full-Bridge Output mode, the ECCP1
module does not provide any dead-band delay. In
general, since only one output is modulated at all times,
dead-band delay is not required. However, there is a
situation where a dead-band delay might be required.
This situation occurs when both of the following
conditions are true:
1.
2.
Figure 15-9 shows an example where the PWM
direction changes from forward to reverse at a near
100% duty cycle. At time t1, the outputs P1A and P1D
become inactive while output P1C becomes active. In
this example, since the turn-off time of the power
devices is longer than the turn-on time, a shoot-through
current may flow through power devices, QC and QD
(see Figure 15-7), for the duration of ‘t’. The same
phenomenon will occur to power devices, QA and QB,
for PWM direction change from reverse to forward.
If changing PWM direction at high duty cycle is required
for an application, one of the following requirements
must be met:
1.
2.
Reduce PWM for a PWM period before
changing directions.
Use switch drivers that can drive the switches off
faster than they can drive them on.
Other options to prevent shoot-through current may
exist.
The direction of the PWM output changes when
the duty cycle of the output is at or near 100%.
The turn-off time of the power switch, including
the power device and driver circuit, is greater
than the turn-on time.
DS39682E-page 142
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 15-8:
PWM DIRECTION CHANGE
Period(1)
SIGNAL
Period
P1A (Active-High)
P1B (Active-High)
DC
P1C (Active-High)
(Note 2)
P1D (Active-High)
DC
Note 1: The direction bit in the ECCP1 Control register (CCP1CON<7>) is written any time during the PWM cycle.
2: When changing directions, the P1A and P1C signals switch before the end of the current PWM cycle at intervals
of 4 TOSC, 16 TOSC or 64 TOSC, depending on the Timer2 prescaler value. The modulated P1B and P1D signals
are inactive at this time.
FIGURE 15-9:
PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
Forward Period
t1
Reverse Period
P1A(1)
P1B(1)
DC
P1C(1)
P1D(1)
DC
tON(2)
External Switch C(1)
tOFF(3)
External Switch D(1)
Potential
Shoot-Through
Current(1)
Note 1:
2:
3:
t = tOFF – tON(2,3)
All signals are shown as active-high.
tON is the turn-on delay of power switch QC and its driver.
tOFF is the turn-off delay of power switch QD and its driver.
© 2009 Microchip Technology Inc.
DS39682E-page 143
PIC18F45J10 FAMILY
15.4.6
Note:
PROGRAMMABLE DEAD-BAND
DELAY
Programmable dead-band delay is not
implemented in 28-pin devices with
standard CCP modules.
In half-bridge applications, where all power switches
are modulated at the PWM frequency at all times, the
power switches normally require more time to turn off
than to turn on. If both the upper and lower power
switches are switched at the same time (one turned on
and the other turned off), both switches may be on for
a short period of time until one switch completely turns
off. During this brief interval, a very high current (shootthrough current) may flow through both power
switches, shorting the bridge supply. To avoid this
potentially destructive shoot-through current from
flowing during switching, turning on either of the power
switches is normally delayed to allow the other switch
to completely turn off.
In the Half-Bridge Output mode, a digitally programmable
dead-band delay is available to avoid shoot-through
current from destroying the bridge power switches. The
delay occurs at the signal transition from the nonactive
state to the active state. See Figure 15-4 for an
illustration. Bits PDC<6:0> of the ECCP1DEL register
(Register 15-2) set the delay period in terms of microcontroller instruction cycles (TCY or 4 TOSC). These bits are
not available in 28-pin devices as the standard CCP
module does not support half-bridge operation.
15.4.7
ENHANCED PWM AUTO-SHUTDOWN
When the ECCP1 is programmed for any of the
Enhanced PWM modes, the active output pins may be
configured for auto-shutdown. Auto-shutdown immediately places the Enhanced PWM output pins into a
defined shutdown state when a shutdown event occurs.
REGISTER 15-2:
A shutdown event can be caused by either of the
comparator modules, a low level on the Fault input pin
(FLT0) or any combination of these three sources. The
comparators may be used to monitor a voltage input
proportional to a current being monitored in the bridge
circuit. If the voltage exceeds a threshold, the
comparator switches state and triggers a shutdown.
Alternatively, a low digital signal on FLT0 can also trigger
a shutdown. The auto-shutdown feature can be disabled
by not selecting any auto-shutdown sources. The autoshutdown sources to be used are selected using the
ECCPAS<2:0> bits (bits<6:4> of the ECCP1AS
register).
When a shutdown occurs, the output pins are
asynchronously placed in their shutdown states,
specified by the PSSAC<1:0> and PSSBD<1:0> bits
(ECCPAS<3:0>). Each pin pair (P1A/P1C and P1B/
P1D) may be set to drive high, drive low or be tri-stated
(not driving). The ECCPASE bit (ECCP1AS<7>) is also
set to hold the Enhanced PWM outputs in their
shutdown states.
The ECCPASE bit is set by hardware when a shutdown
event occurs. If automatic restarts are not enabled, the
ECCPASE bit is cleared by firmware when the cause of
the shutdown clears. If automatic restarts are enabled,
the ECCPASE bit is automatically cleared when the
cause of the auto-shutdown has cleared.
If the ECCPASE bit is set when a PWM period begins,
the PWM outputs remain in their shutdown state for that
entire PWM period. When the ECCPASE bit is cleared,
the PWM outputs will return to normal operation at the
beginning of the next PWM period.
Note:
Writing to the ECCPASE bit is disabled
while a shutdown condition is active.
ECCP1DEL: PWM DEAD-BAND DELAY REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
PRSEN
PDC6(1)
PDC5(1)
PDC4(1)
PDC3(1)
PDC2(1)
PDC1(1)
PDC0(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
PRSEN: PWM Restart Enable bit
1 = Upon auto-shutdown, the ECCPASE bit clears automatically once the shutdown event goes away;
the PWM restarts automatically
0 = Upon auto-shutdown, ECCPASE must be cleared in software to restart the PWM
bit 6-0
PDC<6:0>: PWM Delay Count bits(1)
Delay time, in number of FOSC/4 (4 * TOSC) cycles, between the scheduled and actual time for a PWM
signal to transition to active.
Note 1:
Reserved on 28-pin devices; maintain these bits clear.
DS39682E-page 144
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 15-3:
R/W-0
ECCP1AS: ENHANCED CAPTURE/COMPARE/PWM AUTO-SHUTDOWN
CONTROL REGISTER
R/W-0
ECCPASE
R/W-0
ECCPAS2
ECCPAS1
R/W-0
ECCPAS0
R/W-0
PSSAC1
R/W-0
R/W-0
R/W-0
(1)
PSSAC0
PSSBD1
PSSBD0(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ECCPASE: ECCP Auto-Shutdown Event Status bit
1 = A shutdown event has occurred; ECCP outputs are in shutdown state
0 = ECCP outputs are operating
bit 6-4
ECCPAS<2:0>: ECCP Auto-Shutdown Source Select bits
111 = FLT0, Comparator 1 or Comparator 2
110 = FLT0 or Comparator 2
101 = FLT0 or Comparator 1
100 = FLT0
011 = Either Comparator 1 or 2
010 = Comparator 2 output
001 = Comparator 1 output
000 = Auto-shutdown is disabled
bit 3-2
PSSAC<1:0>: Pins A and C Shutdown State Control bits
1x = Pins A and C are tri-state (40/44-pin devices); PWM output is tri-state (28-pin devices)
01 = Drive Pins A and C to ‘1’
00 = Drive Pins A and C to ‘0’
bit 1-0
PSSBD<1:0>: Pins B and D Shutdown State Control bits(1)
1x = Pins B and D tri-state
01 = Drive Pins B and D to ‘1’
00 = Drive Pins B and D to ‘0’
Note 1:
Reserved on 28-pin devices; maintain these bits clear.
© 2009 Microchip Technology Inc.
DS39682E-page 145
PIC18F45J10 FAMILY
15.4.7.1
Auto-Shutdown and Automatic
Restart
The auto-shutdown feature can be configured to allow
automatic restarts of the module following a shutdown
event. This is enabled by setting the PRSEN bit of the
ECCP1DEL register (ECCP1DEL<7>).
In Shutdown mode with PRSEN = 1 (Figure 15-10), the
ECCPASE bit will remain set for as long as the cause
of the shutdown continues. When the shutdown condition clears, the ECCPASE bit is cleared. If PRSEN = 0
(Figure 15-11), once a shutdown condition occurs, the
ECCPASE bit will remain set until it is cleared by firmware. Once ECCPASE is cleared, the Enhanced PWM
will resume at the beginning of the next PWM period.
Note:
Writing to the ECCPASE bit is disabled
while a shutdown condition is active.
Independent of the PRSEN bit setting, if the autoshutdown source is one of the comparators, the
shutdown condition is a level. The ECCPASE bit
cannot be cleared as long as the cause of the shutdown
persists.
The Auto-Shutdown mode can be forced by writing a ‘1’
to the ECCPASE bit.
FIGURE 15-10:
15.4.8
START-UP CONSIDERATIONS
When the ECCP module is used in the PWM mode, the
application hardware must use the proper external pullup and/or pull-down resistors on the PWM output pins.
When the microcontroller is released from Reset, all of
the I/O pins are in the high-impedance state. The
external circuits must keep the power switch devices in
the OFF state until the microcontroller drives the I/O
pins with the proper signal levels, or activates the PWM
output(s).
The CCP1M<1:0> bits (CCP1CON<1:0>) allow the
user to choose whether the PWM output signals are
active-high or active-low for each pair of PWM output
pins (P1A/P1C and P1B/P1D). The PWM output
polarities must be selected before the PWM pins are
configured as outputs. Changing the polarity configuration while the PWM pins are configured as outputs is
not recommended, since it may result in damage to the
application circuits.
The P1A, P1B, P1C and P1D output latches may not be
in the proper states when the PWM module is initialized.
Enabling the PWM pins for output at the same time as
the ECCP module may cause damage to the application circuit. The ECCP module must be enabled in the
proper output mode and complete a full PWM cycle
before configuring the PWM pins as outputs. The completion of a full PWM cycle is indicated by the TMR2IF
bit being set as the second PWM period begins.
PWM AUTO-SHUTDOWN (PRSEN = 1, AUTO-RESTART ENABLED)
PWM Period
Shutdown Event
ECCPASE bit
PWM Activity
Normal PWM
Start of
PWM Period
FIGURE 15-11:
Shutdown
Shutdown
Event Occurs Event Clears
PWM
Resumes
PWM AUTO-SHUTDOWN (PRSEN = 0, AUTO-RESTART DISABLED)
PWM Period
Shutdown Event
ECCPASE bit
PWM Activity
Normal PWM
Start of
PWM Period
DS39682E-page 146
ECCPASE
Cleared by
Shutdown
Shutdown Firmware PWM
Event Occurs Event Clears
Resumes
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
15.4.9
SETUP FOR PWM OPERATION
The following steps should be taken when configuring
the ECCP module for PWM operation:
1.
Configure the PWM pins, P1A and P1B (and
P1C and P1D, if used), as inputs by setting the
corresponding TRIS bits.
2. Set the PWM period by loading the PR2 register.
3. If auto-shutdown is required:
• Disable auto-shutdown (ECCPASE = 0)
• Configure source (FLT0, Comparator 1 or
Comparator 2)
• Wait for non-shutdown condition
4. Configure the ECCP module for the desired
PWM mode and configuration by loading the
CCP1CON register with the appropriate values:
• Select one of the available output
configurations and direction with the
P1M<1:0> bits.
• Select the polarities of the PWM output
signals with the CCP1M<3:0> bits.
5. Set the PWM duty cycle by loading the CCPR1L
register and CCP1CON<5:4> bits.
6. For Half-Bridge Output mode, set the deadband delay by loading ECCP1DEL<6:0> with
the appropriate value.
7. If auto-shutdown operation is required, load the
ECCP1AS register:
• Select the auto-shutdown sources using the
ECCPAS<2:0> bits.
• Select the shutdown states of the PWM
output pins using the PSSAC<1:0> and
PSSBD<1:0> bits.
• Set the ECCPASE bit (ECCP1AS<7>).
• Configure the comparators using the CMCON
register.
• Configure the comparator inputs as analog
inputs.
8. If auto-restart operation is required, set the
PRSEN bit (ECCP1DEL<7>).
9. Configure and start TMR2:
• Clear the TMR2 interrupt flag bit by clearing
the TMR2IF bit (PIR1<1>).
• Set the TMR2 prescale value by loading the
T2CKPS bits (T2CON<1:0>).
• Enable Timer2 by setting the TMR2ON bit
(T2CON<2>).
10. Enable PWM outputs after a new PWM cycle
has started:
• Wait until TMRx overflows (TMRxIF bit is set).
• Enable the CCP1/P1A, P1B, P1C and/or P1D
pin outputs by clearing the respective TRIS bits.
• Clear the ECCPASE bit (ECCP1AS<7>).
© 2009 Microchip Technology Inc.
15.4.10
OPERATION IN POWER-MANAGED
MODES
In Sleep mode, all clock sources are disabled. Timer2
will not increment and the state of the module will not
change. If the CCP1 pin is driving a value, it will continue to drive that value. When the device wakes up, it
will continue from this state. If Two-Speed Start-ups are
enabled, the initial start-up frequency from INTOSC
and the postscaler may not be stable immediately.
In PRI_IDLE mode, the primary clock will continue to
clock the ECCP module without change. In all other
power-managed modes, the selected power-managed
mode clock will clock Timer2. Other power-managed
mode clocks will most likely be different than the
primary clock frequency.
15.4.10.1
Operation with Fail-Safe
Clock Monitor
If the Fail-Safe Clock Monitor is enabled, a clock failure
will force the device into the power-managed RC_RUN
mode and the OSCFIF bit (PIR2<7>) will be set. The
ECCP will then be clocked from the internal oscillator
clock source, which may have a different clock
frequency than the primary clock.
See the previous section for additional details.
15.4.11
EFFECTS OF A RESET
Both Power-on Reset and subsequent Resets will force
all ports to Input mode and the CCP registers to their
Reset states.
This forces the Enhanced CCP module to reset to a
state compatible with the standard CCP module.
DS39682E-page 147
PIC18F45J10 FAMILY
TABLE 15-3:
Name
INTCON
RCON
REGISTERS ASSOCIATED WITH ECCP1 MODULE AND TIMER1
Bit 7
Bit 6
GIE/GIEH PEIE/GIEL
—
IPEN
Reset
Values
on page
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
CM
RI
TO
PD
POR
BOR
46
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
49
TRISB
PORTB Data Direction Control Register
50
TRISC
PORTC Data Direction Control Register
50
TRISD(1)
PORTD Data Direction Control Register
50
TMR1L
Timer1 Register Low Byte
48
TMR1H
Timer1 Register High Byte
48
T1CON
TMR2
T2CON
RD16
T1RUN
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
Timer2 Register
—
48
48
T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0
48
PR2
Timer2 Period Register
48
CCPR1L
Capture/Compare/PWM Register 1 Low Byte
49
CCPR1H
Capture/Compare/PWM Register 1 High Byte
CCP1CON
ECCP1AS
ECCP1DEL
Legend:
Note 1:
P1M1(1)
P1M0(1)
ECCPASE ECCPAS2
PRSEN
PDC6
(1)
49
DC1B1
DC1B0
CCP1M3
CCP1M2
ECCPAS1
ECCPAS0
PSSAC1
PSSAC0
(1)
(1)
(1)
PDC5
PDC4
(1)
PDC3
PDC2
CCP1M1
CCP1M0
PSSBD1(1) PSSBD0(1)
PDC1(1)
PDC0(1)
49
49
49
— = unimplemented, read as ‘0’. Shaded cells are not used during ECCP operation.
These registers and/or bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 148
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.0
MASTER SYNCHRONOUS
SERIAL PORT (MSSP)
MODULE
16.1
Master SSP (MSSP) Module
Overview
The Master Synchronous Serial Port (MSSP) module is
a serial interface, useful for communicating with other
peripheral or microcontroller devices. These peripheral
devices may be serial EEPROMs, shift registers,
display drivers, A/D converters, etc. The MSSP module
can operate in one of two modes:
• Serial Peripheral Interface (SPI)
• Inter-Integrated Circuit (I2C™)
- Full Master mode
- Slave mode (with general address call)
The I2C interface supports the following modes in
hardware:
• Master mode
• Multi-Master mode
• Slave mode
PIC18F24J10/25J10 (28-pin) devices have one MSSP
module designated as MSSP1. PIC18F44J10/45J10
(40/44-pin) devices have two MSSP modules,
designated as MSSP1 and MSSP2. Each module
operates independently of the other.
Note:
16.2
Throughout this section, generic references to an MSSP module in any of its
operating modes may be interpreted as
being equally applicable to MSSP1 or
MSSP2. Register names and module I/O
signals use the generic designator ‘x’ to
indicate the use of a numeral to distinguish
a particular module, when required.
Control bit names are not individuated.
In devices with more than one MSSP
module, it is very important to pay close
attention to SSPxCON register names.
SSP1CON1 and SSP1CON2 control
different operational aspects of the same
module,
while
SSP1CON1
and
SSP2CON1 control the same features for
two different modules.
Note:
16.3
SPI Mode
The SPI mode allows 8 bits of data to be synchronously
transmitted and received simultaneously. All four
modes of SPI are supported. To accomplish
communication, typically three pins are used:
• Serial Data Out (SDOx) – RC5/SDO1 or
RD2/PSP2/SDO2
• Serial Data In (SDIx) – RC4/SDI1/SDA1 or
RD1/PSP1/SDI2/SDA2
• Serial Clock (SCKx) – RC3/SCK1/SCL1 or
RD0/PSP0/SCK2/SCL2
Additionally, a fourth pin may be used when in a Slave
mode of operation:
• Slave Select (SSx) – RA5/AN4/SS1/C2OUT or
RD3/PSP3/SS2
Figure 16-1 shows the block diagram of the MSSP
module when operating in SPI mode.
FIGURE 16-1:
Internal
Data Bus
Read
SDIx
SSPxSR reg
Control Registers
SDOx
SSx
SSx Control
Enable
2
Clock Select
SSPM<3:0>
SMP:CKE 4
TMR2 Output
2
2
Edge
Select
Prescaler TOSC
4, 16, 64
(
SCKx
)
Data to TX/RX in SSPxSR
TRIS bit
Note:
© 2009 Microchip Technology Inc.
Shift
Clock
bit 0
Edge Select
Additional details are provided under the individual
sections.
Disabling the MSSP module by clearing
the SSPEN (SSPxCON1<5>) bit may not
reset the module. It is recommended to
clear the SSPxSTAT, SSPxCON1 and
SSPxCON2 registers and select the mode
prior to setting the SSPEN bit to enable
the MSSP module.
Write
SSPxBUF reg
Each MSSP module has three associated control
registers. These include a status register (SSPxSTAT)
and two control registers (SSPxCON1 and SSPxCON2).
The use of these registers and their individual configuration bits differ significantly depending on whether the
MSSP module is operated in SPI or I2C mode.
Note:
MSSP BLOCK DIAGRAM
(SPI MODE)
Only port I/O names are used in this diagram for the sake
of brevity. Refer to the text for a full list of multiplexed
functions.
DS39682E-page 149
PIC18F45J10 FAMILY
16.3.1
REGISTERS
SSPxSR is the shift register used for shifting data in or
out. SSPxBUF is the buffer register to which data
bytes are written to or read from.
Each MSSP module has four registers for SPI mode
operation. These are:
In receive operations, SSPxSR and SSPxBUF
together create a double-buffered receiver. When
SSPxSR receives a complete byte, it is transferred to
SSPxBUF and the SSPxIF interrupt is set.
• MSSP Control Register 1 (SSPxCON1)
• MSSP Status Register (SSPxSTAT)
• Serial Receive/Transmit Buffer Register
(SSPxBUF)
• MSSP Shift Register (SSPxSR) – Not directly
accessible
During transmission, the SSPxBUF is not
double-buffered. A write to SSPxBUF will write to both
SSPxBUF and SSPxSR.
SSPxCON1 and SSPxSTAT are the control and status
registers in SPI mode operation. The SSPxCON1
register is readable and writable. The lower 6 bits of
the SSPxSTAT are read-only. The upper two bits of the
SSPxSTAT are read/write.
REGISTER 16-1:
R/W-0
SMP
SSPxSTAT: MSSPx STATUS REGISTER (SPI MODE)
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
(1)
D/A
P
S
R/W
UA
BF
CKE
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SMP: Sample bit
SPI Master mode:
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time
SPI Slave mode:
SMP must be cleared when SPI is used in Slave mode.
bit 6
CKE: SPI Clock Select bit(1)
1 = Transmit occurs on transition from active to Idle clock state
0 = Transmit occurs on transition from Idle to active clock state
bit 5
D/A: Data/Address bit
Used in I2C mode only.
bit 4
P: Stop bit
Used in I2C mode only. This bit is cleared when the MSSPx module is disabled, SSPEN is cleared.
bit 3
S: Start bit
Used in I2C mode only.
bit 2
R/W: Read/Write Information bit
Used in I2C mode only.
bit 1
UA: Update Address bit
Used in I2C mode only.
bit 0
BF: Buffer Full Status bit (Receive mode only)
1 = Receive complete, SSPxBUF is full
0 = Receive not complete, SSPxBUF is empty
Note 1:
Polarity of clock state is set by the CKP bit (SSPxCON1<4>).
DS39682E-page 150
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 16-2:
R/W-0
WCOL
SSPxCON1: MSSPx CONTROL REGISTER 1 (SPI MODE)
R/W-0
R/W-0
(1)
(2)
SSPOV
SSPEN
R/W-0
CKP
R/W-0
SSPM3
(3)
R/W-0
SSPM2
(3)
R/W-0
SSPM1
(3)
R/W-0
SSPM0(3)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
WCOL: Write Collision Detect bit
1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
bit 6
SSPOV: Receive Overflow Indicator bit(1)
SPI Slave mode:
1 = A new byte is received while the SSPxBUF register is still holding the previous data. In case of
overflow, the data in SSPxSR is lost. Overflow can only occur in Slave mode. The user must read
the SSPxBUF, even if only transmitting data, to avoid setting overflow (must be cleared in
software).
0 = No overflow
bit 5
SSPEN: Master Synchronous Serial Port Enable bit(2)
1 = Enables serial port and configures SCKx, SDOx, SDIx and SSx as serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4
CKP: Clock Polarity Select bit
1 = Idle state for clock is a high level
0 = Idle state for clock is a low level
bit 3-0
SSPM<3:0>: Master Synchronous Serial Port Mode Select bits(3)
0101 = SPI Slave mode, clock = SCKx pin, SSx pin control disabled, SSx can be used as I/O pin
0100 = SPI Slave mode, clock = SCKx pin, SSx pin control enabled
0011 = SPI Master mode, clock = TMR2 output/2
0010 = SPI Master mode, clock = FOSC/64
0001 = SPI Master mode, clock = FOSC/16
0000 = SPI Master mode, clock = FOSC/4
Note 1:
2:
3:
In Master mode, the overflow bit is not set since each new reception (and transmission) is initiated by
writing to the SSPxBUF register.
When enabled, these pins must be properly configured as input or output.
Bit combinations not specifically listed here are either reserved or implemented in I2C™ mode only.
© 2009 Microchip Technology Inc.
DS39682E-page 151
PIC18F45J10 FAMILY
16.3.2
OPERATION
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits (SSPxCON1<5:0> and SSPxSTAT<7:6>).
These control bits allow the following to be specified:
•
•
•
•
Master mode (SCKx is the clock output)
Slave mode (SCKx is the clock input)
Clock Polarity (Idle state of SCKx)
Data Input Sample Phase (middle or end of data
output time)
• Clock Edge (output data on rising/falling edge of
SCKx)
• Clock Rate (Master mode only)
• Slave Select mode (Slave mode only)
Each MSSP consists of a transmit/receive shift register
(SSPxSR) and a buffer register (SSPxBUF). The
SSPxSR shifts the data in and out of the device, MSb
first. The SSPxBUF holds the data that was written to the
SSPxSR until the received data is ready. Once the 8 bits
of data have been received, that byte is moved to the
SSPxBUF register. Then, the Buffer Full detect bit, BF
(SSPxSTAT<0>), and the interrupt flag bit, SSPxIF, are
set. This double-buffering of the received data
(SSPxBUF) allows the next byte to start reception before
reading the data that was just received. Any write to the
EXAMPLE 16-1:
LOOP
SSPxBUF register during transmission/reception of data
will be ignored and the Write Collision detect bit, WCOL
(SSPxCON1<7>), will be set. User software must clear
the WCOL bit so that it can be determined if the following
write(s) to the SSPxBUF register completed
successfully.
When the application software is expecting to receive
valid data, the SSPxBUF should be read before the next
byte of data to transfer is written to the SSPxBUF. The
Buffer Full bit, BF (SSPxSTAT<0>), indicates when
SSPxBUF has been loaded with the received data
(transmission is complete). When the SSPxBUF is read,
the BF bit is cleared. This data may be irrelevant if the
SPI is only a transmitter. Generally, the MSSP interrupt
is used to determine when the transmission/reception
has completed. The SSPxBUF must be read and/or
written. If the interrupt method is not going to be used,
then software polling can be done to ensure that a write
collision does not occur. Example 16-1 shows the
loading of the SSP1BUF (SSP1SR) for data
transmission.
The SSPxSR is not directly readable or writable and
can only be accessed by addressing the SSPxBUF
register. Additionally, the SSPxSTAT register indicates
the various status conditions.
LOADING THE SSP1BUF (SSP1SR) REGISTER
BTFSS
BRA
MOVF
SSP1STAT, BF
LOOP
SSP1BUF, W
MOVWF
RXDATA
;Save in user RAM, if data is meaningful
MOVF
MOVWF
TXDATA, W
SSP1BUF
;W reg = contents of TXDATA
;New data to xmit
DS39682E-page 152
;Has data been received (transmit complete)?
;No
;WREG reg = contents of SSP1BUF
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.3.3
ENABLING SPI I/O
To enable the serial port, MSSP Enable bit, SSPEN
(SSPxCON1<5>), must be set. To reset or reconfigure
SPI mode, clear the SSPEN bit, reinitialize the
SSPxCON registers and then set the SSPEN bit. This
configures the SDIx, SDOx, SCKx and SSx pins as
serial port pins. For the pins to behave as the serial port
function, some must have their data direction bits (in
the TRIS register) appropriately programmed as
follows:
• SDIx is automatically controlled by the SPI module
• SDOx must have TRISC<5> (or TRISD<2>) bit
cleared
• SCKx (Master mode) must have TRISC<3> (or
TRISD<0>) bit cleared
• SCKx (Slave mode) must have TRISC<3> (or
TRISD<0>) bit set
• SSx must have TRISA<5> (or TRISD<3>) bit set
FIGURE 16-2:
Any serial port function that is not desired may be
overridden by programming the corresponding data
direction (TRIS) register to the opposite value.
16.3.4
TYPICAL CONNECTION
Figure 16-2 shows a typical connection between two
microcontrollers. The master controller (Processor 1)
initiates the data transfer by sending the SCKx signal.
Data is shifted out of both shift registers on their programmed clock edge and latched on the opposite edge
of the clock. Both processors should be programmed to
the same Clock Polarity (CKP), then both controllers
would send and receive data at the same time.
Whether the data is meaningful (or dummy data)
depends on the application software. This leads to
three scenarios for data transmission:
• Master sends data – Slave sends dummy data
• Master sends data – Slave sends data
• Master sends dummy data – Slave sends data
SPI MASTER/SLAVE CONNECTION
SPI Master SSPM<3:0> = 00xxb
SPI Slave SSPM<3:0> = 010xb
SDOx
SDIx
Serial Input Buffer
(SSPxBUF)
SDIx
Shift Register
(SSPxSR)
MSb
Serial Input Buffer
(SSPxBUF)
LSb
© 2009 Microchip Technology Inc.
Shift Register
(SSPxSR)
MSb
SCKx
PROCESSOR 1
SDOx
Serial Clock
LSb
SCKx
PROCESSOR 2
DS39682E-page 153
PIC18F45J10 FAMILY
16.3.5
MASTER MODE
The master can initiate the data transfer at any time
because it controls the SCKx. The master determines
when the slave (Processor 2, Figure 16-2) will
broadcast data by the software protocol.
In Master mode, the data is transmitted/received as
soon as the SSPxBUF register is written to. If the SPI
is only going to receive, the SDOx output could be disabled (programmed as an input). The SSPxSR register
will continue to shift in the signal present on the SDIx
pin at the programmed clock rate. As each byte is
received, it will be loaded into the SSPxBUF register as
if a normal received byte (interrupts and status bits
appropriately set). This could be useful in receiver
applications as a “Line Activity Monitor” mode.
FIGURE 16-3:
The clock polarity is selected by appropriately
programming the CKP bit (SSPxCON1<4>). This then,
would give waveforms for SPI communication as
shown in Figure 16-3, Figure 16-5 and Figure 16-6,
where the MSB is transmitted first. In Master mode, the
SPI clock rate (bit rate) is user-programmable to be one
of the following:
•
•
•
•
FOSC/4 (or TCY)
FOSC/16 (or 4 • TCY)
FOSC/64 (or 16 • TCY)
Timer2 output/2
This allows a maximum data rate (at 40 MHz) of
10.00 Mbps.
Figure 16-3 shows the waveforms for Master mode.
When the CKE bit is set, the SDOx data is valid before
there is a clock edge on SCKx. The change of the input
sample is shown based on the state of the SMP bit. The
time when the SSPxBUF is loaded with the received
data is shown.
SPI MODE WAVEFORM (MASTER MODE)
Write to
SSPxBUF
SCKx
(CKP = 0
CKE = 0)
SCKx
(CKP = 1
CKE = 0)
4 Clock
Modes
SCKx
(CKP = 0
CKE = 1)
SCKx
(CKP = 1
CKE = 1)
SDOx
(CKE = 0)
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDOx
(CKE = 1)
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDIx
(SMP = 0)
bit 0
bit 7
Input
Sample
(SMP = 0)
SDIx
(SMP = 1)
bit 7
bit 0
Input
Sample
(SMP = 1)
SSPxIF
SSPxSR to
SSPxBUF
DS39682E-page 154
Next Q4 Cycle
after Q2↓
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.3.6
SLAVE MODE
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCKx. When the
last bit is latched, the SSPxIF interrupt flag bit is set.
Before enabling the module in SPI Slave mode, the
clock line must match the proper Idle state. The clock
line can be observed by reading the SCKx pin. The Idle
state is determined by the CKP bit (SSPxCON1<4>).
While in Slave mode, the external clock is supplied by
the external clock source on the SCKx pin. This
external clock must meet the minimum high and low
times as specified in the electrical specifications.
While in Sleep mode, the slave can transmit/receive
data. When a byte is received, the device will wake-up
from Sleep.
16.3.7
SLAVE SELECT
SYNCHRONIZATION
The SSx pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with SSx pin control
enabled (SSPxCON1<3:0> = 04h). When the SSx pin
is low, transmission and reception are enabled and the
FIGURE 16-4:
SDOx pin is driven. When the SSx pin goes high, the
SDOx pin is no longer driven, even if in the middle of a
transmitted byte and becomes a floating output.
External pull-up/pull-down resistors may be desirable
depending on the application.
Note 1: When the SPI is in Slave mode with SSx pin
control enabled (SSPxCON1<3:0> = 0100),
the SPI module will reset if the SSx pin is set
to VDD.
2: If the SPI is used in Slave mode with CKE
set, then the SSx pin control must be
enabled.
When the SPI module resets, the bit counter is forced
to ‘0’. This can be done by either forcing the SSx pin to
a high level or clearing the SSPEN bit.
To emulate two-wire communication, the SDOx pin can
be connected to the SDIx pin. When the SPI needs to
operate as a receiver, the SDOx pin can be configured
as an input. This disables transmissions from the
SDOx. The SDIx can always be left as an input (SDIx
function) since it cannot create a bus conflict.
SLAVE SYNCHRONIZATION WAVEFORM
SSx
SCKx
(CKP = 0
CKE = 0)
SCKx
(CKP = 1
CKE = 0)
Write to
SSPxBUF
SDOx
SDIx
(SMP = 0)
bit 7
bit 6
bit 7
bit 0
bit 0
bit 7
bit 7
Input
Sample
(SMP = 0)
SSPxIF
Interrupt
Flag
SSPxSR to
SSPxBUF
© 2009 Microchip Technology Inc.
Next Q4 Cycle
after Q2↓
DS39682E-page 155
PIC18F45J10 FAMILY
FIGURE 16-5:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
SSx
Optional
SCKx
(CKP = 0
CKE = 0)
SCKx
(CKP = 1
CKE = 0)
Write to
SSPxBUF
SDOx
SDIx
(SMP = 0)
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
bit 0
bit 7
Input
Sample
(SMP = 0)
SSPxIF
Interrupt
Flag
Next Q4 Cycle
after Q2↓
SSPxSR to
SSPxBUF
FIGURE 16-6:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SSx
Not Optional
SCKx
(CKP = 0
CKE = 1)
SCKx
(CKP = 1
CKE = 1)
Write to
SSPxBUF
SDOx
SDIx
(SMP = 0)
bit 7
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
bit 0
Input
Sample
(SMP = 0)
SSPxIF
Interrupt
Flag
SSPxSR to
SSPxBUF
DS39682E-page 156
Next Q4 Cycle
after Q2↓
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.3.8
OPERATION IN POWER-MANAGED
MODES
In SPI Master mode, module clocks may be operating
at a different speed than when in Full-Power mode; in
the case of Sleep mode, all clocks are halted.
In Idle modes, a clock is provided to the peripherals.
That clock should be from the primary clock source, the
secondary clock (Timer1 oscillator at 32.768 kHz) or
the INTOSC source. See Section 3.6 “Clock Sources
and Oscillator Switching” for additional information.
16.3.10
Table 16-1 shows the compatibility between the
standard SPI modes and the states of the CKP and
CKE control bits.
TABLE 16-1:
If the Sleep mode is selected, all module clocks are
halted and the transmission/reception will remain in
that state until the devices wakes. After the device
returns to Run mode, the module will resume
transmitting and receiving data.
In SPI Slave mode, the SPI Transmit/Receive Shift
register operates asynchronously to the device. This
allows the device to be placed in any power-managed
mode and data to be shifted into the SPI
Transmit/Receive Shift register. When all 8 bits have
been received, the MSSP interrupt flag bit will be set
and if enabled, will wake the device.
16.3.9
SPI BUS MODES
Control Bits State
Standard SPI Mode
Terminology
CKP
CKE
0, 0
0
1
0, 1
0
0
1, 0
1
1
1, 1
1
0
In most cases, the speed that the master clocks SPI
data is not important; however, this should be
evaluated for each system.
If MSSP interrupts are enabled, they can wake the controller from Sleep mode, or one of the Idle modes, when
the master completes sending data. If an exit from
Sleep or Idle mode is not desired, MSSP interrupts
should be disabled.
BUS MODE COMPATIBILITY
There is also an SMP bit which controls when the data
is sampled.
16.3.11
SPI CLOCK SPEED AND MODULE
INTERACTIONS
Because MSSP1 and MSSP2 are independent
modules, they can operate simultaneously at different
data rates. Setting the SSPM<3:0> bits of the
SSPxCON1 register determines the rate for the
corresponding module.
An exception is when both modules use Timer2 as a
time base in Master mode. In this instance, any
changes to the Timer2 operation will affect both MSSP
modules equally. If different bit rates are required for
each module, the user should select one of the other
three time base options for one of the modules.
EFFECTS OF A RESET
A Reset disables the MSSP module and terminates the
current transfer.
© 2009 Microchip Technology Inc.
DS39682E-page 157
PIC18F45J10 FAMILY
TABLE 16-2:
Name
REGISTERS ASSOCIATED WITH SPI OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
PSPIE
(1)
IPR1
PSPIP
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
PIR3
SSP2IF
BCL2IF
—
—
—
—
—
—
49
PIE3
SSP2IE
BCL2IE
—
—
—
—
—
—
49
IPR3
SSP2IP
BCL2IP
—
—
—
—
—
—
49
TRISA
—
—
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
50
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
50
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
50
TRISD(1)
SSP1BUF
MSSP1 Receive Buffer/Transmit Register
48
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
48
SSP1STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
48
SSP2BUF
MSSP2 Receive Buffer/Transmit Register
50
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
50
SSP2STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
50
Legend: Shaded cells are not used by the MSSP module in SPI mode.
Note 1: These registers and/or bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 158
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4
I2C Mode
16.4.1
The MSSP module in I 2C mode fully implements all
master and slave functions (including general call
support) and provides interrupts on Start and Stop bits
in hardware to determine a free bus (multi-master
function). The MSSP module implements the standard
mode specifications, as well as 7-bit and 10-bit
addressing.
Two pins are used for data transfer:
• Serial clock (SCLx) – RC3/SCK1/SCL1 or
RD6/SCK2/SCL2
• Serial data (SDAx) – RC4/SDI1/SDA1 or
RD5/SDI2/SDA2
The user must configure these pins as inputs by setting
the associated TRIS bits.
FIGURE 16-7:
MSSP BLOCK DIAGRAM
(I2C™ MODE)
Internal
Data Bus
Read
Write
SCLx
•
•
•
•
MSSP Control Register 1 (SSPxCON1)
MSSP Control Register 2 (SSPxCON2)
MSSP Status Register (SSPxSTAT)
Serial Receive/Transmit Buffer Register
(SSPxBUF)
• MSSP Shift Register (SSPxSR) – Not directly
accessible
• MSSP Address Register (SSPxADD)
SSPxCON1, SSPxCON2 and SSPxSTAT are the
control and status registers in I2C mode operation. The
SSPxCON1 and SSPxCON2 registers are readable
and writable. The lower 6 bits of the SSPxSTAT are
read-only. The upper two bits of the SSPxSTAT are
read/write.
Many of the bits in SSPxCON2 assume different
functions, depending on whether the module is operating in Master or Slave mode; bits<5:2> also assume
different names in Slave mode. The different aspects of
SSPxCON2 are shown in Register 16-5 (for Master
mode) and Register 16-6 (Slave mode).
SSPxSR is the shift register used for shifting data in or
out. SSPxBUF is the buffer register to which data bytes
are written to or read from.
SSPxSR reg
SSPxADD register holds the slave device address
when the MSSP is configured in I2C Slave mode. When
the MSSP is configured in Master mode, the lower
seven bits of SSPxADD act as the Baud Rate
Generator reload value.
MSb
LSb
Match Detect
Addr Match
Address Mask
In receive operations, SSPxSR and SSPxBUF together
create a double-buffered receiver. When SSPxSR
receives a complete byte, it is transferred to SSPxBUF
and the SSPxIF interrupt is set.
SSPxADD reg
Start and
Stop bit Detect
Note:
The MSSP module has six registers for I2C operation.
These are:
SSPxBUF reg
Shift
Clock
SDAx
REGISTERS
Set, Reset
S, P bits
(SSPxSTAT reg)
Only port I/O names are used in this diagram for
the sake of brevity. Refer to the text for a full list of
multiplexed functions.
© 2009 Microchip Technology Inc.
During transmission, the SSPxBUF is not
double-buffered. A write to SSPxBUF will write to both
SSPxBUF and SSPxSR.
Note:
Disabling the MSSP module by clearing
the SSPEN (SSPxCON1<5>) bit may not
reset the module. It is recommended to
clear the SSPxSTAT, SSPxCON1 and
SSPxCON2 registers and select the mode
prior to setting the SSPEN bit to enable
the MSSP module.
DS39682E-page 159
PIC18F45J10 FAMILY
REGISTER 16-3:
R/W-0
SSPxSTAT: MSSPx STATUS REGISTER (I2C™ MODE)
R/W-0
SMP
CKE
R-0
R-0
R-0
R-0
R0
R-0
D/A
(1)
(1)
R/W
UA
BF
P
S
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SMP: Slew Rate Control bit
In Master or Slave mode:
1 = Slew rate control disabled for Standard Speed mode (100 kHz and 1 MHz)
0 = Slew rate control enabled for High-Speed mode (400 kHz)
bit 6
CKE: SMBus Select bit
In Master or Slave mode:
1 = Enable SMBus specific inputs
0 = Disable SMBus specific inputs
bit 5
D/A: Data/Address bit
In Master mode:
Reserved.
In Slave mode:
1 = Indicates that the last byte received or transmitted was data
0 = Indicates that the last byte received or transmitted was address
bit 4
P: Stop bit(1)
1 = Indicates that a Stop bit has been detected last
0 = Stop bit was not detected last
bit 3
S: Start bit(1)
1 = Indicates that a Start bit has been detected last
0 = Start bit was not detected last
bit 2
R/W: Read/Write Information bit (I2C mode only)
In Slave mode:(2)
1 = Read
0 = Write
In Master mode:(3)
1 = Transmit is in progress
0 = Transmit is not in progress
bit 1
UA: Update Address bit (10-Bit Slave mode only)
1 = Indicates that the user needs to update the address in the SSPxADD register
0 = Address does not need to be updated
bit 0
BF: Buffer Full Status bit
In Transmit mode:
1 = SSPxBUF is full
0 = SSPxBUF is empty
In Receive mode:
1 = SSPxBUF is full (does not include the ACK and Stop bits)
0 = SSPxBUF is empty (does not include the ACK and Stop bits)
Note 1:
2:
3:
This bit is cleared on Reset and when SSPEN is cleared.
This bit holds the R/W bit information following the last address match. This bit is only valid from the
address match to the next Start bit, Stop bit or not ACK bit.
ORing this bit with SEN, RSEN, PEN, RCEN or ACKEN will indicate if the MSSP is in Active mode.
DS39682E-page 160
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 16-4:
R/W-0
SSPxCON1: MSSPx CONTROL REGISTER 1 (I2C™ MODE)
R/W-0
WCOL
R/W-0
SSPOV
SSPEN
(1)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
CKP
SSPM3
SSPM2
SSPM1
SSPM0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
WCOL: Write Collision Detect bit
In Master Transmit mode:
1 = A write to the SSPxBUF register was attempted while the I2C conditions were not valid for a
transmission to be started (must be cleared in software)
0 = No collision
In Slave Transmit mode:
1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in
software)
0 = No collision
In Receive mode (Master or Slave modes):
This is a “don’t care” bit.
bit 6
SSPOV: Receive Overflow Indicator bit
In Receive mode:
1 = A byte is received while the SSPxBUF register is still holding the previous byte (must be cleared in
software)
0 = No overflow
In Transmit mode:
This is a “don’t care” bit in Transmit mode.
bit 5
SSPEN: Master Synchronous Serial Port Enable bit(1)
1 = Enables the serial port and configures the SDAx and SCLx pins as the serial port pins
0 = Disables serial port and configures these pins as I/O port pins
bit 4
CKP: SCK Release Control bit
In Slave mode:
1 = Release clock
0 = Holds clock low (clock stretch), used to ensure data setup time
In Master mode:
Unused in this mode.
bit 3-0
SSPM<3:0>: Synchronous Serial Port Mode Select bits
1111 = I2C Slave mode, 10-bit address with Start and Stop bit interrupts enabled
1110 = I2C Slave mode, 7-bit address with Start and Stop bit interrupts enabled
1011 = I2C Firmware Controlled Master mode (slave Idle)
1000 = I2C Master mode, clock = FOSC/(4 * (SSPxADD + 1))
0111 = I2C Slave mode, 10-bit address
0110 = I2C Slave mode, 7-bit address
Bit combinations not specifically listed here are either reserved or implemented in SPI mode only.
Note 1:
When enabled, the SDAx and SCLx pins must be configured as inputs.
© 2009 Microchip Technology Inc.
DS39682E-page 161
PIC18F45J10 FAMILY
REGISTER 16-5:
R/W-0
GCEN
SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ MASTER MODE)
R/W-0
ACKSTAT
R/W-0
ACKDT
(1)
R/W-0
(2)
ACKEN
R/W-0
(2)
RCEN
R/W-0
PEN
(2)
R/W-0
(2)
RSEN
R/W-0
SEN(2)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
GCEN: General Call Enable bit
Unused in Master mode.
bit 6
ACKSTAT: Acknowledge Status bit (Master Transmit mode only)
1 = Acknowledge was not received from slave
0 = Acknowledge was received from slave
bit 5
ACKDT: Acknowledge Data bit (Master Receive mode only)(1)
1 = Not Acknowledge
0 = Acknowledge
bit 4
ACKEN: Acknowledge Sequence Enable bit(2)
1 = Initiate Acknowledge sequence on SDAx and SCLx pins and transmit ACKDT data bit.
Automatically cleared by hardware.
0 = Acknowledge sequence Idle
bit 3
RCEN: Receive Enable bit (Master Receive mode only)(2)
1 = Enables Receive mode for I2C
0 = Receive Idle
bit 2
PEN: Stop Condition Enable bit(2)
1 = Initiate Stop condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Stop condition Idle
bit 1
RSEN: Repeated Start Condition Enable bit(2)
1 = Initiate Repeated Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Repeated Start condition Idle
bit 0
SEN: Start Condition Enable bit(2)
1 = Initiate Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Start condition Idle
Note 1:
2:
Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive.
If the I2C module is active, these bits may not be set (no spooling) and the SSPxBUF may not be written
(or writes to the SSPxBUF are disabled).
DS39682E-page 162
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 16-6:
SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ SLAVE MODE)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
GCEN
ACKSTAT
ADMSK5
ADMSK4
ADMSK3
ADMSK2
ADMSK1
SEN(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
GCEN: General Call Enable bit
1 = Enable interrupt when a general call address (0000h) is received in the SSPxSR
0 = General call address disabled
bit 6
ACKSTAT: Acknowledge Status bit
Unused in Slave mode.
bit 5-2
ADMSK<5:2>: Slave Address Mask Select bits
1 = Masking of corresponding bits of SSPxADD enabled
0 = Masking of corresponding bits of SSPxADD disabled
bit 1
ADMSK1: Slave Address Least Significant bit(s) Mask Select bit
In 7-Bit Addressing mode:
1 = Masking of SSPxADD<1> only enabled
0 = Masking of SSPxADD<1> only disabled
In 10-Bit Addressing mode:
1 = Masking of SSPxADD<1:0> enabled
0 = Masking of SSPxADD<1:0> disabled
bit 0
SEN: Stretch Enable bit(1)
1 = Clock stretching is enabled for both slave transmit and slave receive (stretch enabled)
0 = Clock stretching is disabled
Note 1:
If the I2C module is active, this bit may not be set (no spooling) and the SSPxBUF may not be written (or
writes to the SSPxBUF are disabled).
© 2009 Microchip Technology Inc.
DS39682E-page 163
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16.4.2
OPERATION
The MSSP module functions are enabled by setting the
MSSP Enable bit, SSPEN (SSPxCON1<5>).
The SSPxCON1 register allows control of the
operation.
Four
mode
selection
(SSPxCON1<3:0>) allow one of the following
modes to be selected:
I 2C
bits
I 2C
• I2C Master mode,
clock = (FOSC/4) x (SSPxADD + 1)
• I 2C Slave mode (7-bit address)
• I 2C Slave mode (10-bit address)
• I 2C Slave mode (7-bit address) with Start and
Stop bit interrupts enabled
• I 2C Slave mode (10-bit address) with Start and
Stop bit interrupts enabled
• I 2C Firmware Controlled Master mode,
slave is Idle
Selection of any I 2C mode, with the SSPEN bit set,
forces the SCLx and SDAx pins to be open-drain,
provided these pins are programmed to inputs by
setting the appropriate TRISC or TRISD bits. To ensure
proper operation of the module, pull-up resistors must
be provided externally to the SCLx and SDAx pins.
16.4.3
SLAVE MODE
In Slave mode, the SCLx and SDAx pins must be
configured as inputs (TRISC<4:3> set). The MSSP
module will override the input state with the output data
when required (slave-transmitter).
The I 2C Slave mode hardware will always generate an
interrupt on an exact address match. In addition,
address masking will also allow the hardware to generate an interrupt for more than one address (up to 31 in
7-bit addressing and up to 63 in 10-bit addressing).
Through the mode select bits, the user can also choose
to interrupt on Start and Stop bits.
When an address is matched, or the data transfer after
an address match is received, the hardware automatically will generate the Acknowledge (ACK) pulse
and load the SSPxBUF register with the received value
currently in the SSPxSR register.
Any combination of the following conditions will cause
the MSSP module not to give this ACK pulse:
• The Buffer Full bit, BF (SSPxSTAT<0>), was set
before the transfer was received.
• The MSSP Overflow bit, SSPOV
(SSPxCON1<6>), was set before the transfer was
received.
In this case, the SSPxSR register value is not loaded
into the SSPxBUF, but the SSPxIF bit is set. The BF bit
is cleared by reading the SSPxBUF register, while the
SSPOV bit is cleared through software.
DS39682E-page 164
The SCLx clock input must have a minimum high and
low for proper operation. The high and low times of the
I2C specification, as well as the requirement of the
MSSP module, are shown in timing parameter 100 and
parameter 101.
16.4.3.1
Addressing
Once the MSSP module has been enabled, it waits for
a Start condition to occur. Following the Start condition,
the 8 bits are shifted into the SSPxSR register. All
incoming bits are sampled with the rising edge of the
clock (SCLx) line. The value of register SSPxSR<7:1>
is compared to the value of the SSPxADD register. The
address is compared on the falling edge of the eighth
clock (SCLx) pulse. If the addresses match and the BF
and SSPOV bits are clear, the following events occur:
1.
2.
3.
4.
The SSPxSR register value is loaded into the
SSPxBUF register.
The Buffer Full bit, BF, is set.
An ACK pulse is generated.
The MSSP Interrupt Flag bit, SSPxIF, is set (and
interrupt is generated, if enabled) on the falling
edge of the ninth SCLx pulse.
In 10-Bit Addressing mode, two address bytes need to
be received by the slave. The five Most Significant bits
(MSbs) of the first address byte specify if this is a 10-bit
address. Bit R/W (SSPxSTAT<2>) must specify a write
so the slave device will receive the second address byte.
For a 10-bit address, the first byte would equal ‘11110
A9 A8 0’, where ‘A9’ and ‘A8’ are the two MSbs of the
address. The sequence of events for 10-Bit Addressing
mode is as follows, with steps 7 through 9 for the
slave-transmitter:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Receive first (high) byte of address (bits,
SSPxIF, BF and UA (SSPxSTAT<1>), are set).
Update the SSPxADD register with second (low)
byte of address (clears bit, UA, and releases the
SCLx line).
Read the SSPxBUF register (clears bit, BF) and
clear flag bit, SSPxIF.
Receive second (low) byte of address (bits,
SSPxIF, BF and UA, are set).
Update the SSPxADD register with the first
(high) byte of address. If match releases SCLx
line, this will clear bit, UA.
Read the SSPxBUF register (clears bit, BF) and
clear flag bit, SSPxIF.
Receive Repeated Start condition.
Receive first (high) byte of address (bits,
SSPxIF and BF, are set).
Read the SSPxBUF register (clears bit, BF) and
clear flag bit, SSPxIF.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.3.2
Address Masking
Masking an address bit causes that bit to become a
“don’t care”. When one address bit is masked, two
addresses will be Acknowledged and cause an
interrupt. It is possible to mask more than one address
bit at a time, which makes it possible to Acknowledge
up to 31 addresses in 7-Bit Addressing mode and up to
63 addresses in 10-Bit Addressing mode (see
Example 16-2).
The I2C Slave behaves the same way, whether
address masking is used or not. However, when
address masking is used, the I2C slave can
Acknowledge multiple addresses and cause interrupts.
When this occurs, it is necessary to determine which
address caused the interrupt by checking SSPxBUF.
In 7-Bit Addressing mode, Address Mask bits,
ADMSK<5:1>
(SSPxCON2<5:1>),
mask
the
corresponding address bits in the SSPxADD register. For
any ADMSK bits that are set (ADMSK<n> = 1), the corresponding address bit is ignored (SSPxADD<n> = x).
EXAMPLE 16-2:
For the module to issue an address Acknowledge, it is
sufficient to match only on addresses that do not have an
active address mask.
In 10-Bit Addressing mode, ADMSK<5:2> bits mask
the corresponding address bits in the SSPxADD register. In addition, ADMSK1 simultaneously masks the two
LSbs of the address (SSPxADD<1:0>). For any
ADMSK bits that are active (ADMSK<n> = 1), the corresponding address bit is ignored (SSPxADD<n> = x).
Also note that although in 10-Bit Addressing mode, the
upper address bits reuse part of the SSPxADD register
bits, the address mask bits do not interact with those
bits. They only affect the lower address bits.
Note 1: ADMSK1 masks the two Least Significant
bits of the address.
2: The two Most Significant bits of the
address are not affected by address
masking.
ADDRESS MASKING EXAMPLES
7-Bit Addressing:
SSPxADD<7:1>= A0h (1010000) (SSPxADD<0> is assumed to be ‘0’)
ADMSK<5:1>
= 00111
Addresses Acknowledged: A0h, A2h, A4h, A6h, A8h, AAh, ACh, AEh
10-Bit Addressing:
SSPxADD<7:0>= A0h (10100000) (the two MSbs of the address are ignored in this example, since they are
not affected by masking)
ADMSK<5:1>
= 00111
Addresses Acknowledged: A0h, A1h, A2h, A3h, A4h, A5h, A6h, A7h, A8h, A9h, AAh, ABh, ACh, ADh, AEh, AFh
© 2009 Microchip Technology Inc.
DS39682E-page 165
PIC18F45J10 FAMILY
16.4.3.3
Reception
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPxSTAT
register is cleared. The received address is loaded into
the SSPxBUF register and the SDAx line is held low
(ACK).
When the address byte overflow condition exists, then
the no Acknowledge (ACK) pulse is given. An overflow
condition is defined as either bit, BF (SSPxSTAT<0>),
is set, or bit, SSPOV (SSPxCON1<6>), is set.
An MSSP interrupt is generated for each data transfer
byte. The interrupt flag bit, SSPxIF, must be cleared in
software. The SSPxSTAT register is used to determine
the status of the byte.
If SEN is enabled (SSPxCON2<0> = 1), SCKx/SCLx
(RC3 or RD0) will be held low (clock stretch) following
each data transfer. The clock must be released by
setting bit, CKP (SSPxCON1<4>). See Section 16.4.4
“Clock Stretching” for more details.
16.4.3.4
Transmission
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPxSTAT register is set. The received address is
loaded into the SSPxBUF register. The ACK pulse will
be sent on the ninth bit and pin RC3 or RD6 is held low,
regardless of SEN (see Section 16.4.4 “Clock
Stretching” for more details). By stretching the clock,
the master will be unable to assert another clock pulse
until the slave is done preparing the transmit data. The
transmit data must be loaded into the SSPxBUF register which also loads the SSPxSR register. Then pin
RC3 or RD0 should be enabled by setting bit, CKP
(SSPxCON1<4>). The eight data bits are shifted out on
the falling edge of the SCLx input. This ensures that the
SDAx signal is valid during the SCLx high time
(Figure 16-9).
The ACK pulse from the master-receiver is latched on
the rising edge of the ninth SCLx input pulse. If the
SDAx line is high (not ACK), then the data transfer is
complete. In this case, when the ACK is latched by the
slave, the slave logic is reset (resets SSPxSTAT
register) and the slave monitors for another occurrence
of the Start bit. If the SDAx line was low (ACK), the next
transmit data must be loaded into the SSPxBUF register. Again, pin RC3 or RD0 must be enabled by setting
bit CKP.
An MSSP interrupt is generated for each data transfer
byte. The SSPxIF bit must be cleared in software and
the SSPxSTAT register is used to determine the status
of the byte. The SSPxIF bit is set on the falling edge of
the ninth clock pulse.
DS39682E-page 166
© 2009 Microchip Technology Inc.
© 2009 Microchip Technology Inc.
2
A6
CKP
3
A5
4
A4
5
A3
6
A2
(CKP does not reset to ‘0’ when SEN = 0)
SSPOV (SSPxCON1<6>)
BF (SSPxSTAT<0>)
SSPxIF (PIR1<3> or PIR3<7>)
1
SCLx
S
A7
Receiving Address
7
A1
8
9
ACK
R/W = 0
1
D7
3
D5
4
D4
Cleared in software
SSPxBUF is read
2
D6
5
D3
Receiving Data
6
D2
7
D1
8
D0
9
ACK
1
D7
2
D6
3
D5
4
D4
5
D3
Receiving Data
6
D2
7
D1
8
D0
Bus master
terminates
transfer
P
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
9
ACK
FIGURE 16-8:
SDAx
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I2C™ SLAVE MODE TIMING WITH SEN = 0 (RECEPTION, 7-BIT ADDRESSING)
DS39682E-page 167
DS39682E-page 168
2
Data in
sampled
1
A6
CKP (SSPxCON<4>)
BF (SSPxSTAT<0>)
SSPxIF (PIR1<3> or PIR3<7>)
S
A7
3
4
A4
5
A3
6
A2
Receiving Address
A5
7
A1
8
R/W = 0
9
ACK
3
D5
4
5
D3
SSPxBUF is written in software
6
D2
Transmitting Data
D4
Cleared in software
2
D6
CKP is set in software
Clear by reading
SCLx held low
while CPU
responds to SSPxIF
1
D7
7
8
D0
9
From SSPxIF ISR
D1
ACK
1
D7
4
D4
5
D3
Cleared in software
3
D5
6
D2
CKP is set in software
SSPxBUF is written in software
2
D6
7
8
D0
9
ACK
From SSPxIF ISR
D1
Transmitting Data
P
FIGURE 16-9:
SCLx
SDAx
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I2C™ SLAVE MODE TIMING (TRANSMISSION, 7-BIT ADDRESSING)
© 2009 Microchip Technology Inc.
© 2009 Microchip Technology Inc.
2
1
3
1
5
0
7
A8
8
UA is set indicating that
the SSPxADD needs to be
updated
SSPxBUF is written with
contents of SSPxSR
6
A9
9
(CKP does not reset to ‘0’ when SEN = 0)
UA (SSPxSTAT<1>)
SSPOV (SSPxCON1<6>)
BF (SSPxSTAT<0>)
CKP
4
1
Cleared in software
SSPxIF (PIR1<3> or PIR3<7>)
1
SCLx
S
1
ACK
R/W = 0
A7
2
4
A4
5
A3
6
A2
8
9
A0 ACK
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware
when SSPxADD is updated
with low byte of address
7
A1
Cleared in software
3
A5
Dummy read of SSPxBUF
to clear BF flag
1
A6
Receive Second Byte of Address
1
D7
4
5
6
Cleared in software
3
D3 D2
7
D1
Cleared by hardware when
SSPxADD is updated with high
byte of address
2
D6 D5 D4
Receive Data Byte
Clock is held low until
update of SSPxADD has
taken place
8
9
1
2
4
5
6
Cleared in software
3
D3 D2
Receive Data Byte
D0 ACK D7 D6 D5 D4
7
8
D1 D0
9
P
Bus master
terminates
transfer
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
ACK
FIGURE 16-10:
SDAx
Receive First Byte of Address
Clock is held low until
update of SSPxADD has
taken place
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I2C™ SLAVE MODE TIMING WITH SEN = 0 (RECEPTION, 10-BIT ADDRESSING)
DS39682E-page 169
DS39682E-page 170
2
1
3
1
4
1
CKP (SSPxCON1<4>)
UA (SSPxSTAT<1>)
BF (SSPxSTAT<0>)
5
0
6
7
A9 A8
8
UA is set indicating that
the SSPxADD needs to be
updated
SSPxBUF is written with
contents of SSPxSR
SSPxIF (PIR1<3> or PIR3<7>)
1
SCLx
S
1
9
ACK
R/W = 0
1
3
4
5
Cleared in software
2
7
UA is set indicating that
SSPxADD needs to be
updated
8
A0
Cleared by hardware when
SSPxADD is updated with low
byte of address
6
A6 A5 A4 A3 A2 A1
Receive Second Byte of Address
Dummy read of SSPxBUF
to clear BF flag
A7
9
ACK
2
3
1
4
1
Cleared in software
1
1
5
0
6
8
9
ACK
R/W = 1
1
2
4
5
6
CKP is set in software
9
P
Completion of
data transmission
clears BF flag
8
ACK
Bus master
terminates
transfer
CKP is automatically cleared in hardware, holding SCLx low
7
D4 D3 D2 D1 D0
Cleared in software
3
D7 D6 D5
Transmitting Data Byte
Clock is held low until
CKP is set to ‘1’
Write of SSPxBUF
BF flag is clear
initiates transmit
at the end of the
third address sequence
7
A9 A8
Cleared by hardware when
SSPxADD is updated with high
byte of address.
Dummy read of SSPxBUF
to clear BF flag
Sr
1
Receive First Byte of Address
Clock is held low until
update of SSPxADD has
taken place
FIGURE 16-11:
SDAx
Receive First Byte of Address
Clock is held low until
update of SSPxADD has
taken place
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I2C™ SLAVE MODE TIMING (TRANSMISSION, 10-BIT ADDRESSING)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.4
CLOCK STRETCHING
Both 7-Bit and 10-Bit Slave modes implement
automatic clock stretching during a transmit sequence.
The SEN bit (SSPxCON2<0>) allows clock stretching
to be enabled during receives. Setting SEN will cause
the SCLx pin to be held low at the end of each data
receive sequence.
16.4.4.1
Clock Stretching for 7-Bit Slave
Receive Mode (SEN = 1)
In 7-Bit Slave Receive mode, on the falling edge of the
ninth clock at the end of the ACK sequence, if the BF
bit is set, the CKP bit in the SSPxCON1 register is
automatically cleared, forcing the SCLx output to be
held low. The CKP being cleared to ‘0’ will assert the
SCLx line low. The CKP bit must be set in the user’s
ISR before reception is allowed to continue. By holding
the SCLx line low, the user has time to service the ISR
and read the contents of the SSPxBUF before the
master device can initiate another receive sequence.
This will prevent buffer overruns from occurring (see
Figure 16-13).
Note 1: If the user reads the contents of the
SSPxBUF before the falling edge of the
ninth clock, thus clearing the BF bit, the
CKP bit will not be cleared and clock
stretching will not occur.
2: The CKP bit can be set in software
regardless of the state of the BF bit. The
user should be careful to clear the BF bit
in the ISR before the next receive
sequence in order to prevent an overflow
condition.
16.4.4.2
16.4.4.3
Clock Stretching for 7-Bit Slave
Transmit Mode
The 7-Bit Slave Transmit mode implements clock
stretching by clearing the CKP bit after the falling edge
of the ninth clock, if the BF bit is clear. This occurs
regardless of the state of the SEN bit.
The user’s ISR must set the CKP bit before transmission is allowed to continue. By holding the SCLx line
low, the user has time to service the ISR and load the
contents of the SSPxBUF before the master device
can initiate another transmit sequence (see
Figure 16-9).
Note 1: If the user loads the contents of
SSPxBUF, setting the BF bit before the
falling edge of the ninth clock, the CKP bit
will not be cleared and clock stretching
will not occur.
2: The CKP bit can be set in software
regardless of the state of the BF bit.
16.4.4.4
Clock Stretching for 10-Bit Slave
Transmit Mode
In 10-Bit Slave Transmit mode, clock stretching is controlled during the first two address sequences by the
state of the UA bit, just as it is in 10-bit Slave Receive
mode. The first two addresses are followed by a third
address sequence which contains the high-order bits
of the 10-bit address and the R/W bit set to ‘1’. After
the third address sequence is performed, the UA bit is
not set, the module is now configured in Transmit
mode and clock stretching is controlled by the BF flag
as in 7-Bit Slave Transmit mode (see Figure 16-11).
Clock Stretching for 10-Bit Slave
Receive Mode (SEN = 1)
In 10-Bit Slave Receive mode during the address
sequence, clock stretching automatically takes place
but CKP is not cleared. During this time, if the UA bit is
set after the ninth clock, clock stretching is initiated.
The UA bit is set after receiving the upper byte of the
10-bit address and following the receive of the second
byte of the 10-bit address with the R/W bit cleared to
‘0’. The release of the clock line occurs upon updating
SSPxADD. Clock stretching will occur on each data
receive sequence as described in 7-bit mode.
Note:
If the user polls the UA bit and clears it by
updating the SSPxADD register before the
falling edge of the ninth clock occurs and if
the user hasn’t cleared the BF bit by reading the SSPxBUF register before that time,
then the CKP bit will still NOT be asserted
low. Clock stretching on the basis of the
state of the BF bit only occurs during a
data sequence, not an address sequence.
© 2009 Microchip Technology Inc.
DS39682E-page 171
PIC18F45J10 FAMILY
16.4.4.5
Clock Synchronization and
the CKP bit
When the CKP bit is cleared, the SCLx output is forced
to ‘0’. However, clearing the CKP bit will not assert the
SCLx output low until the SCLx output is already sampled low. Therefore, the CKP bit will not assert the
SCLx line until an external I2C master device has
FIGURE 16-12:
already asserted the SCLx line. The SCLx output will
remain low until the CKP bit is set and all other
devices on the I2C bus have deasserted SCLx. This
ensures that a write to the CKP bit will not violate the
minimum high time requirement for SCLx (see
Figure 16-12).
CLOCK SYNCHRONIZATION TIMING
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
SDAx
DX
DX – 1
SCLx
CKP
Master Device
Asserts Clock
Master Device
Deasserts Clock
WR
SSPxCON
DS39682E-page 172
© 2009 Microchip Technology Inc.
© 2009 Microchip Technology Inc.
2
A6
CKP
SSPOV (SSPxCON1<6>)
BF (SSPxSTAT<0>)
SSPxIF (PIR1<3> or PIR3<7>)
1
SCLx
S
A7
3
A5
4
A4
5
A3
6
A2
Receiving Address
7
A1
8
9
ACK
R/W = 0
3
D5
4
D4
5
D3
Cleared in software
2
D6
If BF is cleared
prior to the falling
edge of the 9th clock,
CKP will not be reset
to ‘0’ and no clock
stretching will occur
SSPxBUF is read
1
D7
Receiving Data
6
D2
7
D1
9
1
D7
BF is set after falling
edge of the 9th clock,
CKP is reset to ‘0’ and
clock stretching occurs
8
D0
ACK
3
4
D4
5
D3
Receiving Data
D5
CKP
written
to ‘1’ in
software
2
D6
Clock is held low until
CKP is set to ‘1’
6
D2
7
D1
8
D0
Bus master
terminates
transfer
P
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
9
ACK
Clock is not held low
because ACK = 1
FIGURE 16-13:
SDAx
Clock is not held low
because buffer full bit is
clear prior to falling edge
of 9th clock
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I2C™ SLAVE MODE TIMING WITH SEN = 1 (RECEPTION, 7-BIT ADDRESSING)
DS39682E-page 173
DS39682E-page 174
2
1
3
1
UA (SSPxSTAT<1>)
SSPOV (SSPxCON1<6>)
BF (SSPxSTAT<0>)
CKP
4
1
5
0
6
7
A9 A8
8
UA is set indicating that
the SSPxADD needs to be
updated
SSPxBUF is written with
contents of SSPxSR
Cleared in software
SSPxIF (PIR1<3> or PIR3<7>)
1
SCLx
S
1
9
ACK
R/W = 0
A7
2
4
A4
5
A3
6
A2
Cleared in software
3
A5
7
A1
8
A0
Note: An update of the SSPxADD
register before the falling
edge of the ninth clock will
have no effect on UA and
UA will remain set.
UA is set indicating that
SSPxADD needs to be
updated
Cleared by hardware when
SSPxADD is updated with low
byte of address after falling edge
of ninth clock
Dummy read of SSPxBUF
to clear BF flag
1
A6
Receive Second Byte of Address
9
ACK
2
4
5
6
Cleared in software
3
D3 D2
7
8
1
4
5
6
Cleared in software
3
CKP written to ‘1’
in software
2
D3 D2
Receive Data Byte
D7 D6 D5 D4
Note: An update of the SSPxADD register before the
falling edge of the ninth clock will have no effect
on UA and UA will remain set.
9
ACK
Clock is held low until
CKP is set to ‘1’
D1 D0
Cleared by hardware when
SSPxADD is updated with high
byte of address after falling edge
of ninth clock
Dummy read of SSPxBUF
to clear BF flag
1
D7 D6 D5 D4
Receive Data Byte
Clock is held low until
update of SSPxADD has
taken place
7
8
9
ACK
Bus master
terminates
transfer
P
SSPOV is set
because SSPxBUF is
still full. ACK is not sent.
D1 D0
Clock is not held low
because ACK = 1
FIGURE 16-14:
SDAx
Receive First Byte of Address
Clock is held low until
update of SSPxADD has
taken place
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I2C™ SLAVE MODE TIMING WITH SEN = 1 (RECEPTION, 10-BIT ADDRESSING)
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16.4.5
GENERAL CALL ADDRESS
SUPPORT
If the general call address matches, the SSPxSR is
transferred to the SSPxBUF, the BF flag bit is set
(eighth bit) and on the falling edge of the ninth bit (ACK
bit), the SSPxIF interrupt flag bit is set.
The addressing procedure for the I2C bus is such that
the first byte after the Start condition usually
determines which device will be the slave addressed by
the master. The exception is the general call address
which can address all devices. When this address is
used, all devices should, in theory, respond with an
Acknowledge.
When the interrupt is serviced, the source for the
interrupt can be checked by reading the contents of the
SSPxBUF. The value can be used to determine if the
address was device-specific or a general call address.
In 10-bit mode, the SSPxADD is required to be updated
for the second half of the address to match and the UA
bit is set (SSPxSTAT<1>). If the general call address is
sampled when the GCEN bit is set, while the slave is
configured in 10-Bit Addressing mode, then the second
half of the address is not necessary, the UA bit will not
be set and the slave will begin receiving data after the
Acknowledge (Figure 16-15).
The general call address is one of eight addresses
reserved for specific purposes by the I2C protocol. It
consists of all ‘0’s with R/W = 0.
The general call address is recognized when the
General Call Enable bit, GCEN, is enabled
(SSPxCON2<7> set). Following a Start bit detect, 8 bits
are shifted into the SSPxSR and the address is
compared against the SSPxADD. It is also compared to
the general call address and fixed in hardware.
FIGURE 16-15:
SLAVE MODE GENERAL CALL ADDRESS SEQUENCE
(7 OR 10-BIT ADDRESSING MODE)
Address is compared to General Call Address
after ACK, set interrupt
SCLx
S
1
2
3
4
5
Receiving Data
R/W = 0
General Call Address
SDAx
ACK D7
6
7
8
9
1
ACK
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
9
SSPxIF
BF (SSPxSTAT<0>)
Cleared in software
SSPxBUF is read
SSPOV (SSPxCON1<6>)
‘0’
GCEN (SSPxCON2<7>)
‘1’
© 2009 Microchip Technology Inc.
DS39682E-page 175
PIC18F45J10 FAMILY
MASTER MODE
Note:
Master mode is enabled by setting and clearing the
appropriate SSPM bits in SSPxCON1 and by setting
the SSPEN bit. In Master mode, the SCLx and SDAx
lines are manipulated by the MSSP hardware.
Master mode of operation is supported by interrupt
generation on the detection of the Start and Stop
conditions. The Stop (P) and Start (S) bits are cleared
from a Reset or when the MSSP module is disabled.
Control of the I 2C bus may be taken when the P bit is
set, or the bus is Idle, with both the S and P bits clear.
The following events will cause the MSSP Interrupt
Flag bit, SSPxIF, to be set (and MSSP interrupt, if
enabled):
In Firmware Controlled Master mode, user code
conducts all I 2C bus operations based on Start and
Stop bit conditions.
•
•
•
•
•
Once Master mode is enabled, the user has six
options.
1.
2.
3.
4.
5.
6.
Assert a Start condition on SDAx and SCLx.
Assert a Repeated Start condition on SDAx and
SCLx.
Write to the SSPxBUF register initiating
transmission of data/address.
Configure the I2C port to receive data.
Generate an Acknowledge condition at the end
of a received byte of data.
Generate a Stop condition on SDAx and SCLx.
FIGURE 16-16:
The MSSP module, when configured in
I2C Master mode, does not allow queueing
of events. For instance, the user is not
allowed to initiate a Start condition and
immediately write the SSPxBUF register to
initiate transmission before the Start condition is complete. In this case, the
SSPxBUF will not be written to and the
WCOL bit will be set, indicating that a write
to the SSPxBUF did not occur.
Start condition
Stop condition
Data transfer byte transmitted/received
Acknowledge transmit
Repeated Start
MSSP BLOCK DIAGRAM (I2C™ MASTER MODE)
Internal
Data Bus
Read
SSPM<3:0>
SSPxADD<6:0>
Write
SSPxBUF
SDAx
Baud
Rate
Generator
Shift
Clock
SDAx In
SCLx In
Bus Collision
DS39682E-page 176
LSb
Start bit, Stop bit,
Acknowledge
Generate
Start bit Detect,
Stop bit Detect,
Write Collision Detect,
Clock Arbitration,
State Counter for
End of XMIT/RCV
Clock Cntl
SCLx
Receive Enable
SSPxSR
MSb
Clock Arbitrate/WCOL Detect
(hold off clock source)
16.4.6
Set/Reset S, P, WCOL (SSPxSTAT, SSPxCON1);
Set SSPxIF, BCLxIF;
Reset ACKSTAT, PEN (SSPxCON2)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.6.1
I2C Master Mode Operation
The master device generates all of the serial clock
pulses and the Start and Stop conditions. A transfer is
ended with a Stop condition or with a Repeated Start
condition. Since the Repeated Start condition is also
the beginning of the next serial transfer, the I2C bus will
not be released.
In Master Transmitter mode, serial data is output
through SDAx, while SCLx outputs the serial clock. The
first byte transmitted contains the slave address of the
receiving device (7 bits) and the Read/Write (R/W) bit.
In this case, the R/W bit will be logic ‘0’. Serial data is
transmitted 8 bits at a time. After each byte is transmitted, an Acknowledge bit is received. Start and Stop
conditions are output to indicate the beginning and the
end of a serial transfer.
In Master Receive mode, the first byte transmitted
contains the slave address of the transmitting device
(7 bits) and the R/W bit. In this case, the R/W bit will be
logic ‘1’. Thus, the first byte transmitted is a 7-bit slave
address followed by a ‘1’ to indicate the receive bit.
Serial data is received via SDAx, while SCLx outputs
the serial clock. Serial data is received 8 bits at a time.
After each byte is received, an Acknowledge bit is
transmitted. Start and Stop conditions indicate the
beginning and end of transmission.
The Baud Rate Generator used for the SPI mode
operation is used to set the SCLx clock frequency for
either 100 kHz, 400 kHz or 1 MHz I2C operation. See
Section 16.4.7 “Baud Rate” for more detail.
© 2009 Microchip Technology Inc.
A typical transmit sequence would go as follows:
1.
The user generates a Start condition by setting
the Start Enable bit, SEN (SSPxCON2<0>).
2. SSPxIF is set. The MSSP module will wait the
required start time before any other operation
takes place.
3. The user loads the SSPxBUF with the slave
address to transmit.
4. Address is shifted out the SDAx pin until all 8 bits
are transmitted.
5. The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
SSPxCON2 register (SSPxCON2<6>).
6. The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the
SSPxIF bit.
7. The user loads the SSPxBUF with eight bits of
data.
8. Data is shifted out the SDAx pin until all 8 bits
are transmitted.
9. The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
SSPxCON2 register (SSPxCON2<6>).
10. The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the
SSPxIF bit.
11. The user generates a Stop condition by setting
the Stop Enable bit, PEN (SSPxCON2<2>).
12. Interrupt is generated once the Stop condition is
complete.
DS39682E-page 177
PIC18F45J10 FAMILY
16.4.7
BAUD RATE
2
In I C Master mode, the Baud Rate Generator (BRG)
reload value is placed in the lower 7 bits of the
SSPxADD register (Figure 16-17). When a write
occurs to SSPxBUF, the Baud Rate Generator will
automatically begin counting. The BRG counts down to
‘0’ and stops until another reload has taken place. The
BRG count is decremented twice per instruction cycle
(TCY) on the Q2 and Q4 clocks. In I2C Master mode, the
BRG is reloaded automatically.
Once the given operation is complete (i.e., transmission of the last data bit is followed by ACK), the internal
clock will automatically stop counting and the SCLx pin
will remain in its last state.
FIGURE 16-17:
16.4.7.1
Baud Rate and Module
Interdependence
Because MSSP1 and MSSP2 are independent, they
can operate simultaneously in I2C Master mode at
different baud rates. This is done by using different
BRG reload values for each module.
Because this mode derives its basic clock source from
the system clock, any changes to the clock will affect
both modules in the same proportion. It may be possible to change one or both baud rates back to a
previous value by changing the BRG reload value.
BAUD RATE GENERATOR BLOCK DIAGRAM
SSPM<3:0>
SSPM<3:0>
Reload
SCLx
Control
CLKO
SSPxADD<6:0>
Reload
BRG Down Counter
FOSC/4
I2C™ CLOCK RATE w/BRG
TABLE 16-3:
Note 1:
Table 16-3 demonstrates clock rates based on
instruction cycles and the BRG value loaded into
SSPxADD.
FCY
FCY * 2
BRG Value
FSCL
(2 Rollovers of BRG)
10 MHz
20 MHz
18h
400 kHz(1)
10 MHz
20 MHz
1Fh
312.5 kHz
10 MHz
20 MHz
63h
100 kHz
4 MHz
8 MHz
09h
400 kHz(1)
4 MHz
8 MHz
0Ch
308 kHz
4 MHz
8 MHz
27h
100 kHz
1 MHz
2 MHz
02h
333 kHz(1)
1 MHz
2 MHz
09h
100 kHz
1 MHz
2 MHz
00h
1 MHz(1)
2
2
The I C™ interface does not conform to the 400 kHz I C specification (which applies to rates greater than
100 kHz) in all details, but may be used with care where higher rates are required by the application.
DS39682E-page 178
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.7.2
Clock Arbitration
Clock arbitration occurs when the master, during any
receive, transmit or Repeated Start/Stop condition,
deasserts the SCLx pin (SCLx allowed to float high).
When the SCLx pin is allowed to float high, the Baud
Rate Generator (BRG) is suspended from counting
until the SCLx pin is actually sampled high. When the
FIGURE 16-18:
SDAx
SCLx pin is sampled high, the Baud Rate Generator is
reloaded with the contents of SSPxADD<6:0> and
begins counting. This ensures that the SCLx high time
will always be at least one BRG rollover count in the
event that the clock is held low by an external device
(Figure 16-18).
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
DX
DX – 1
SCLx deasserted but slave holds
SCLx low (clock arbitration)
SCLx allowed to transition high
SCLx
BRG decrements on
Q2 and Q4 cycles
BRG
Value
03h
02h
01h
00h (hold off)
03h
02h
SCLx is sampled high, reload takes
place and BRG starts its count
BRG
Reload
© 2009 Microchip Technology Inc.
DS39682E-page 179
PIC18F45J10 FAMILY
16.4.8
I2C MASTER MODE START
CONDITION TIMING
Note:
To initiate a Start condition, the user sets the Start
Enable bit, SEN (SSPxCON2<0>). If the SDAx and
SCLx pins are sampled high, the Baud Rate Generator
is reloaded with the contents of SSPxADD<6:0> and
starts its count. If SCLx and SDAx are both sampled
high when the Baud Rate Generator times out (TBRG),
the SDAx pin is driven low. The action of the SDAx
being driven low while SCLx is high is the Start condition and causes the S bit (SSPxSTAT<3>) to be set.
Following this, the Baud Rate Generator is reloaded
with the contents of SSPxADD<6:0> and resumes its
count. When the Baud Rate Generator times out
(TBRG), the SEN bit (SSPxCON2<0>) will be automatically cleared by hardware. The Baud Rate Generator is
suspended, leaving the SDAx line held low and the
Start condition is complete.
FIGURE 16-19:
16.4.8.1
If, at the beginning of the Start condition,
the SDAx and SCLx pins are already sampled low, or if during the Start condition, the
SCLx line is sampled low before the SDAx
line is driven low, a bus collision occurs.
The Bus Collision Interrupt Flag, BCLxIF,
is set, the Start condition is aborted and
the I2C module is reset into its Idle state.
WCOL Status Flag
If the user writes the SSPxBUF when a Start sequence
is in progress, the WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
Note:
Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPxCON2 is disabled until the Start
condition is complete.
FIRST START BIT TIMING
Write to SEN bit occurs here
Set S bit (SSPxSTAT<3>)
SDAx = 1,
SCLx = 1
TBRG
At completion of Start bit,
hardware clears SEN bit
and sets SSPxIF bit
TBRG
Write to SSPxBUF occurs here
1st bit
SDAx
2nd bit
TBRG
SCLx
TBRG
S
DS39682E-page 180
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.9
I2C MASTER MODE REPEATED
START CONDITION TIMING
Note 1: If RSEN is programmed while any other
event is in progress, it will not take effect.
A Repeated Start condition occurs when the RSEN bit
(SSPxCON2<1>) is programmed high and the I2C logic
module is in the Idle state. When the RSEN bit is set,
the SCLx pin is asserted low. When the SCLx pin is
sampled low, the Baud Rate Generator is loaded with
the contents of SSPxADD<6:0> and begins counting.
The SDAx pin is released (brought high) for one Baud
Rate Generator count (TBRG). When the Baud Rate
Generator times out, if SDAx is sampled high, the SCLx
pin will be deasserted (brought high). When SCLx is
sampled high, the Baud Rate Generator is reloaded
with the contents of SSPxADD<6:0> and begins counting. SDAx and SCLx must be sampled high for one
TBRG. This action is then followed by assertion of the
SDAx pin (SDAx = 0) for one TBRG while SCLx is high.
Following this, the RSEN bit (SSPxCON2<1>) will be
automatically cleared and the Baud Rate Generator will
not be reloaded, leaving the SDAx pin held low. As
soon as a Start condition is detected on the SDAx and
SCLx pins, the S bit (SSPxSTAT<3>) will be set. The
SSPxIF bit will not be set until the Baud Rate Generator
has timed out.
2: A bus collision during the Repeated Start
condition occurs if:
• SDAx is sampled low when SCLx
goes from low-to-high.
• SCLx goes low before SDAx is
asserted low. This may indicate that
another master is attempting to
transmit a data ‘1’.
Immediately following the SSPxIF bit getting set, the
user may write the SSPxBUF with the 7-bit address in
7-bit mode or the default first address in 10-bit mode.
After the first eight bits are transmitted and an ACK is
received, the user may then transmit an additional eight
bits of address (10-bit mode) or eight bits of data (7-bit
mode).
16.4.9.1
If the user writes the SSPxBUF when a Repeated Start
sequence is in progress, the WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
Note:
FIGURE 16-20:
WCOL Status Flag
Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPxCON2 is disabled until the Repeated
Start condition is complete.
REPEATED START CONDITION WAVEFORM
S bit set by hardware
Write to SSPxCON2 occurs here: SDAx = 1,
SCLx (no change)
SDAx = 1,
SCLx = 1
TBRG
TBRG
At completion of Start bit,
hardware clears RSEN bit
and sets SSPxIF
TBRG
1st bit
SDAx
RSEN bit set by hardware
on falling edge of ninth clock,
end of Xmit
Write to SSPxBUF occurs here
TBRG
SCLx
TBRG
Sr = Repeated Start
© 2009 Microchip Technology Inc.
DS39682E-page 181
PIC18F45J10 FAMILY
16.4.10
I2C MASTER MODE
TRANSMISSION
Transmission of a data byte, a 7-bit address or the
other half of a 10-bit address is accomplished by simply
writing a value to the SSPxBUF register. This action will
set the Buffer Full flag bit, BF, and allow the Baud Rate
Generator to begin counting and start the next transmission. Each bit of address/data will be shifted out
onto the SDAx pin after the falling edge of SCLx is
asserted (see data hold time specification
parameter 106). SCLx is held low for one Baud Rate
Generator rollover count (TBRG). Data should be valid
before SCLx is released high (see data setup time
specification parameter 107). When the SCLx pin is
released high, it is held that way for TBRG. The data on
the SDAx pin must remain stable for that duration and
some hold time after the next falling edge of SCLx.
After the eighth bit is shifted out (the falling edge of the
eighth clock), the BF flag is cleared and the master
releases SDAx. This allows the slave device being
addressed to respond with an ACK bit during the ninth
bit time if an address match occurred, or if data was
received properly. The status of ACK is written into the
ACKDT bit on the falling edge of the ninth clock. If the
master receives an Acknowledge, the Acknowledge
Status bit, ACKSTAT, is cleared; if not, the bit is set.
After the ninth clock, the SSPxIF bit is set and the
master clock (Baud Rate Generator) is suspended until
the next data byte is loaded into the SSPxBUF, leaving
SCLx low and SDAx unchanged (Figure 16-21).
After the write to the SSPxBUF, each bit of the address
will be shifted out on the falling edge of SCLx until all
seven address bits and the R/W bit are completed. On
the falling edge of the eighth clock, the master will
deassert the SDAx pin, allowing the slave to respond
with an Acknowledge. On the falling edge of the ninth
clock, the master will sample the SDAx pin to see if the
address was recognized by a slave. The status of the
ACK bit is loaded into the ACKSTAT status bit
(SSPxCON2<6>). Following the falling edge of the
ninth clock transmission of the address, the SSPxIF is
set, the BF flag is cleared and the Baud Rate Generator
is turned off until another write to the SSPxBUF takes
place, holding SCLx low and allowing SDAx to float.
16.4.10.1
BF Status Flag
In Transmit mode, the BF bit (SSPxSTAT<0>) is set
when the CPU writes to SSPxBUF and is cleared when
all 8 bits are shifted out.
16.4.10.2
WCOL Status Flag
The user should verify that the WCOL is clear after
each write to SSPxBUF to ensure the transfer is
correct. In all cases, WCOL must be cleared in
software.
16.4.10.3
ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit (SSPxCON2<6>)
is cleared when the slave has sent an Acknowledge
(ACK = 0) and is set when the slave does not Acknowledge (ACK = 1). A slave sends an Acknowledge when
it has recognized its address (including a general call),
or when the slave has properly received its data.
16.4.11
I2C MASTER MODE RECEPTION
Master mode reception is enabled by programming the
Receive Enable bit, RCEN (SSPxCON2<3>).
Note:
The MSSP module must be in an Idle state
before the RCEN bit is set or the RCEN bit
will be disregarded.
The Baud Rate Generator begins counting, and on
each rollover, the state of the SCLx pin changes
(high-to-low/low-to-high) and data is shifted into the
SSPxSR. After the falling edge of the eighth clock, the
receive enable flag is automatically cleared, the contents of the SSPxSR are loaded into the SSPxBUF, the
BF flag bit is set, the SSPxIF flag bit is set and the Baud
Rate Generator is suspended from counting, holding
SCLx low. The MSSP is now in Idle state awaiting the
next command. When the buffer is read by the CPU,
the BF flag bit is automatically cleared. The user can
then send an Acknowledge bit at the end of reception
by setting the Acknowledge Sequence Enable bit,
ACKEN (SSPxCON2<4>).
16.4.11.1
BF Status Flag
In receive operation, the BF bit is set when an address
or data byte is loaded into SSPxBUF from SSPxSR. It
is cleared when the SSPxBUF register is read.
16.4.11.2
SSPOV Status Flag
In receive operation, the SSPOV bit is set when 8 bits
are received into the SSPxSR and the BF flag bit is
already set from a previous reception.
16.4.11.3
WCOL Status Flag
If the user writes the SSPxBUF when a receive is
already in progress (i.e., SSPxSR is still shifting in a
data byte), the WCOL bit is set and the contents of the
buffer are unchanged (the write doesn’t occur).
If the user writes to the SSPxBUF when a transmit is
already in progress (i.e., SSPxSR is still shifting out a
data byte), the WCOL is set and the contents of the buffer are unchanged (the write doesn’t occur) after 2 TCY
after the SSPxBUF write. If SSPxBUF is rewritten
within 2 TCY, the WCOL bit is set and SSPxBUF is
updated. This may result in a corrupted transfer.
DS39682E-page 182
© 2009 Microchip Technology Inc.
© 2009 Microchip Technology Inc.
S
R/W
PEN
SEN
BF (SSPxSTAT<0>)
SSPxIF
SCLx
SDAx
A6
A5
A4
A3
A2
A1
3
4
5
Cleared in software
2
6
7
8
9
After Start condition, SEN cleared by hardware
SSPxBUF written
1
D7
1
SCLx held low
while CPU
responds to SSPxIF
ACK = 0
R/W = 0
SSPxBUF written with 7-bit address and R/W
start transmit
A7
Transmit Address to Slave
3
D5
4
D4
5
D3
6
D2
7
D1
8
D0
SSPxBUF is written in software
Cleared in software service routine
from MSSP interrupt
2
D6
Transmitting Data or Second Half
of 10-bit Address
P
ACKSTAT in
SSPxCON2 = 1
Cleared in software
9
ACK
From slave, clear ACKSTAT bit (SSPxCON2<6>)
FIGURE 16-21:
SEN = 0
Write SSPxCON2<0> (SEN = 1)
Start condition begins
PIC18F45J10 FAMILY
I2C™ MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESSING)
DS39682E-page 183
DS39682E-page 184
S
ACKEN
SSPOV
BF
(SSPxSTAT<0>)
SDAx = 0, SCLx = 1
while CPU
responds to SSPxIF
SSPxIF
SCLx
SDAx
1
A7
2
4
5
Cleared in software
3
6
A6 A5 A4 A3 A2
Transmit Address to Slave
7
A1
8
9
R/W = 1
ACK
2
3
5
6
7
8
D0
9
ACK
2
3
4
5
6
7
Cleared in software
Set SSPxIF interrupt
at end of Acknowledge
sequence
Data shifted in on falling edge of CLK
1
D7 D6 D5 D4 D3 D2 D1
Cleared in
software
Set SSPxIF at end
of receive
9
ACK is not sent
ACK
P
Set SSPxIF interrupt
at end of Acknowledge sequence
Bus master
terminates
transfer
Set P bit
(SSPxSTAT<4>)
and SSPxIF
PEN bit = 1
written here
SSPOV is set because
SSPxBUF is still full
8
D0
RCEN cleared
automatically
Set ACKEN, start Acknowledge sequence
SDAx = ACKDT = 1
Receiving Data from Slave
RCEN = 1, start
next receive
ACK from Master,
SDAx = ACKDT = 0
Last bit is shifted into SSPxSR and
contents are unloaded into SSPxBUF
Cleared in software
Set SSPxIF interrupt
at end of receive
4
Cleared in software
1
D7 D6 D5 D4 D3 D2 D1
Receiving Data from Slave
RCEN cleared
automatically
Master configured as a receiver
by programming SSPxCON2<3> (RCEN = 1)
FIGURE 16-22:
SEN = 0
Write to SSPxBUF occurs here,
ACK from Slave
start XMIT
Write to SSPxCON2<0> (SEN = 1),
begin Start condition
Write to SSPxCON2<4>
to start Acknowledge sequence
SDAx = ACKDT (SSPxCON2<5>) = 0
PIC18F45J10 FAMILY
I 2C™ MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESSING)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.12
ACKNOWLEDGE SEQUENCE
TIMING
16.4.13
A Stop bit is asserted on the SDAx pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit, PEN (SSPxCON2<2>). At the end of a
receive/transmit, the SCLx line is held low after the falling edge of the ninth clock. When the PEN bit is set, the
master will assert the SDAx line low. When the SDAx
line is sampled low, the Baud Rate Generator is
reloaded and counts down to 0. When the Baud Rate
Generator times out, the SCLx pin will be brought high
and one TBRG (Baud Rate Generator rollover count)
later, the SDAx pin will be deasserted. When the SDAx
pin is sampled high while SCLx is high, the P bit
(SSPxSTAT<4>) is set. A TBRG later, the PEN bit is
cleared and the SSPxIF bit is set (Figure 16-24).
An Acknowledge sequence is enabled by setting the
Acknowledge Sequence Enable bit, ACKEN
(SSPxCON2<4>). When this bit is set, the SCLx pin is
pulled low and the contents of the Acknowledge data bit
are presented on the SDAx pin. If the user wishes to
generate an Acknowledge, then the ACKDT bit should
be cleared. If not, the user should set the ACKDT bit
before starting an Acknowledge sequence. The Baud
Rate Generator then counts for one rollover period
(TBRG) and the SCLx pin is deasserted (pulled high).
When the SCLx pin is sampled high (clock arbitration),
the Baud Rate Generator counts for TBRG. The SCLx pin
is then pulled low. Following this, the ACKEN bit is automatically cleared, the Baud Rate Generator is turned off
and the MSSP module then goes into Idle mode
(Figure 16-23).
16.4.12.1
16.4.13.1
WCOL Status Flag
If the user writes the SSPxBUF when a Stop sequence
is in progress, then the WCOL bit is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
WCOL Status Flag
If the user writes the SSPxBUF when an Acknowledge
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
FIGURE 16-23:
STOP CONDITION TIMING
ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here,
write to SSPxCON2
ACKEN = 1, ACKDT = 0
ACKEN automatically cleared
TBRG
TBRG
SDAx
D0
SCLx
8
ACK
9
SSPxIF
SSPxIF set at
the end of receive
Note: TBRG = one Baud Rate Generator period.
© 2009 Microchip Technology Inc.
Cleared in
software
Cleared in
software
SSPxIF set at the end
of Acknowledge sequence
DS39682E-page 185
PIC18F45J10 FAMILY
FIGURE 16-24:
STOP CONDITION RECEIVE OR TRANSMIT MODE
SCLx = 1 for TBRG, followed by SDAx = 1 for TBRG
after SDAx sampled high. P bit (SSPxSTAT<4>) is set.
Write to SSPxCON2,
set PEN
PEN bit (SSPxCON2<2>) is cleared by
hardware and the SSPxIF bit is set
Falling edge of
9th clock
TBRG
SCLx
SDAx
ACK
P
TBRG
TBRG
TBRG
SCLx brought high after TBRG
SDAx asserted low before rising edge of clock
to set up Stop condition
Note: TBRG = one Baud Rate Generator period.
16.4.14
SLEEP OPERATION
I2C
While in Sleep mode, the
module can receive
addresses or data and when an address match or
complete byte transfer occurs, wake the processor
from Sleep (if the MSSP interrupt is enabled).
16.4.15
EFFECTS OF A RESET
A Reset disables the MSSP module and terminates the
current transfer.
16.4.16
MULTI-MASTER MODE
In Multi-Master mode, the interrupt generation on the
detection of the Start and Stop conditions allows the
determination of when the bus is free. The Stop (P) and
Start (S) bits are cleared from a Reset or when the
MSSP module is disabled. Control of the I 2C bus may
be taken when the P bit (SSPxSTAT<4>) is set, or the
bus is Idle, with both the S and P bits clear. When the
bus is busy, enabling the MSSP interrupt will generate
the interrupt when the Stop condition occurs.
In multi-master operation, the SDAx line must be
monitored for arbitration to see if the signal level is the
expected output level. This check is performed in
hardware with the result placed in the BCLxIF bit.
The states where arbitration can be lost are:
•
•
•
•
•
Address Transfer
Data Transfer
A Start Condition
A Repeated Start Condition
An Acknowledge Condition
16.4.17
MULTI-MASTER COMMUNICATION,
BUS COLLISION AND BUS
ARBITRATION
Multi-Master mode support is achieved by bus arbitration. When the master outputs address/data bits onto
the SDAx pin, arbitration takes place when the master
outputs a ‘1’ on SDAx, by letting SDAx float high, and
another master asserts a ‘0’. When the SCLx pin floats
high, data should be stable. If the expected data on
SDAx is a ‘1’ and the data sampled on the SDAx
pin = 0, then a bus collision has taken place. The
master will set the Bus Collision Interrupt Flag, BCLxIF
and reset the I2C port to its Idle state (Figure 16-25).
If a transmit was in progress when the bus collision
occurred, the transmission is halted, the BF flag is
cleared, the SDAx and SCLx lines are deasserted and
the SSPxBUF can be written to. When the user services
the bus collision Interrupt Service Routine, and if the I2C
bus is free, the user can resume communication by
asserting a Start condition.
If a Start, Repeated Start, Stop or Acknowledge condition
was in progress when the bus collision occurred, the
condition is aborted, the SDAx and SCLx lines are deasserted and the respective control bits in the SSPxCON2
register are cleared. When the user services the bus
collision Interrupt Service Routine, and if the I2C bus is
free, the user can resume communication by asserting a
Start condition.
The master will continue to monitor the SDAx and SCLx
pins. If a Stop condition occurs, the SSPxIF bit will be set.
A write to the SSPxBUF will start the transmission of
data at the first data bit regardless of where the
transmitter left off when the bus collision occurred.
In Multi-Master mode, the interrupt generation on the
detection of Start and Stop conditions allows the determination of when the bus is free. Control of the I2C bus can
be taken when the P bit is set in the SSPxSTAT register,
or the bus is Idle and the S and P bits are cleared.
DS39682E-page 186
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 16-25:
BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
Data changes
while SCLx = 0
SDAx line pulled low
by another source
SDAx released
by master
Sample SDAx. While SCLx is high,
data doesn’t match what is driven
by the master.
Bus collision has occurred.
SDAx
SCLx
Set bus collision
interrupt (BCLxIF)
BCLxIF
© 2009 Microchip Technology Inc.
DS39682E-page 187
PIC18F45J10 FAMILY
16.4.17.1
Bus Collision During a Start
Condition
During a Start condition, a bus collision occurs if:
a)
b)
SDAx or SCLx are sampled low at the beginning
of the Start condition (Figure 16-26).
SCLx is sampled low before SDAx is asserted
low (Figure 16-27).
During a Start condition, both the SDAx and the SCLx
pins are monitored.
If the SDAx pin is sampled low during this count, the
BRG is reset and the SDAx line is asserted early
(Figure 16-28). If, however, a ‘1’ is sampled on the
SDAx pin, the SDAx pin is asserted low at the end of
the BRG count. The Baud Rate Generator is then
reloaded and counts down to 0. If the SCLx pin is
sampled as ‘0’ during this time, a bus collision does not
occur. At the end of the BRG count, the SCLx pin is
asserted low.
Note:
If the SDAx pin is already low, or the SCLx pin is
already low, then all of the following occur:
• the Start condition is aborted;
• the BCLxIF flag is set; and
• the MSSP module is reset to its Idle state
(Figure 16-26).
The Start condition begins with the SDAx and SCLx
pins deasserted. When the SDAx pin is sampled high,
the Baud Rate Generator is loaded from
SSPxADD<6:0> and counts down to ‘0’. If the SCLx pin
is sampled low while SDAx is high, a bus collision
occurs, because it is assumed that another master is
attempting to drive a data ‘1’ during the Start condition.
FIGURE 16-26:
The reason that bus collision is not a factor
during a Start condition is that no two bus
masters can assert a Start condition at the
exact same time. Therefore, one master
will always assert SDAx before the other.
This condition does not cause a bus collision because the two masters must be
allowed to arbitrate the first address
following the Start condition. If the address
is the same, arbitration must be allowed to
continue into the data portion, Repeated
Start or Stop conditions.
BUS COLLISION DURING START CONDITION (SDAx ONLY)
SDAx goes low before the SEN bit is set.
Set BCLxIF,
S bit and SSPxIF set because
SDAx = 0, SCLx = 1.
SDAx
SCLx
Set SEN, enable Start
condition if SDAx = 1, SCLx = 1
SEN cleared automatically because of bus collision.
MSSP module reset into Idle state.
SEN
BCLxIF
SDAx sampled low before
Start condition. Set BCLxIF.
S bit and SSPxIF set because
SDAx = 0, SCLx = 1.
SSPxIF and BCLxIF are
cleared in software
S
SSPxIF
SSPxIF and BCLxIF are
cleared in software
DS39682E-page 188
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 16-27:
BUS COLLISION DURING START CONDITION (SCLx = 0)
SDAx = 0, SCLx = 1
TBRG
TBRG
SDAx
Set SEN, enable Start
sequence if SDAx = 1, SCLx = 1
SCLx
SCLx = 0 before SDAx = 0,
bus collision occurs. Set BCLxIF.
SEN
SCLx = 0 before BRG time-out,
bus collision occurs. Set BCLxIF.
BCLxIF
Interrupt cleared
in software
S
‘0’
‘0’
SSPxIF
‘0’
‘0’
FIGURE 16-28:
BRG RESET DUE TO SDAx ARBITRATION DURING START CONDITION
SDAx = 0, SCLx = 1
Set S
Less than TBRG
SDAx
Set SSPxIF
TBRG
SDAx pulled low by other master.
Reset BRG and assert SDAx.
SCLx
S
SCLx pulled low after BRG
time-out
SEN
BCLxIF
Set SEN, enable Start
sequence if SDAx = 1, SCLx = 1
‘0’
S
SSPxIF
SDAx = 0, SCLx = 1,
set SSPxIF
© 2009 Microchip Technology Inc.
Interrupts cleared
in software
DS39682E-page 189
PIC18F45J10 FAMILY
16.4.17.2
Bus Collision During a Repeated
Start Condition
If SDAx is low, a bus collision has occurred (i.e., another
master is attempting to transmit a data ‘0’, see
Figure 16-29). If SDAx is sampled high, the BRG is
reloaded and begins counting. If SDAx goes from
high-to-low before the BRG times out, no bus collision
occurs because no two masters can assert SDAx at
exactly the same time.
During a Repeated Start condition, a bus collision
occurs if:
a)
b)
A low level is sampled on SDAx when SCLx
goes from low level to high level.
SCLx goes low before SDAx is asserted low,
indicating that another master is attempting to
transmit a data ‘1’.
If SCLx goes from high-to-low before the BRG times
out and SDAx has not already been asserted, a bus
collision occurs. In this case, another master is
attempting to transmit a data ‘1’ during the Repeated
Start condition (see Figure 16-30).
When the user deasserts SDAx and the pin is allowed
to float high, the BRG is loaded with SSPxADD<6:0>
and counts down to 0. The SCLx pin is then deasserted
and when sampled high, the SDAx pin is sampled.
FIGURE 16-29:
If, at the end of the BRG time-out, both SCLx and SDAx
are still high, the SDAx pin is driven low and the BRG
is reloaded and begins counting. At the end of the
count, regardless of the status of the SCLx pin, the
SCLx pin is driven low and the Repeated Start
condition is complete.
BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
SDAx
SCLx
Sample SDAx when SCLx goes high.
If SDAx = 0, set BCLxIF and release SDAx and SCLx.
RSEN
BCLxIF
Cleared in software
S
‘0’
SSPxIF
‘0’
FIGURE 16-30:
BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG
TBRG
SDAx
SCLx
BCLxIF
RSEN
S
SCLx goes low before SDAx,
set BCLxIF. Release SDAx and SCLx.
Interrupt cleared
in software
‘0’
SSPxIF
DS39682E-page 190
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
16.4.17.3
Bus Collision During a Stop
Condition
The Stop condition begins with SDAx asserted low.
When SDAx is sampled low, the SCLx pin is allowed to
float. When the pin is sampled high (clock arbitration),
the Baud Rate Generator is loaded with
SSPxADD<6:0> and counts down to 0. After the BRG
times out, SDAx is sampled. If SDAx is sampled low, a
bus collision has occurred. This is due to another
master attempting to drive a data ‘0’ (Figure 16-31). If
the SCLx pin is sampled low before SDAx is allowed to
float high, a bus collision occurs. This is another case
of another master attempting to drive a data ‘0’
(Figure 16-32).
Bus collision occurs during a Stop condition if:
a)
b)
After the SDAx pin has been deasserted and
allowed to float high, SDAx is sampled low after
the BRG has timed out.
After the SCLx pin is deasserted, SCLx is
sampled low before SDAx goes high.
FIGURE 16-31:
BUS COLLISION DURING A STOP CONDITION (CASE 1)
TBRG
TBRG
TBRG
SDAx
SDAx sampled
low after TBRG,
set BCLxIF
SDAx asserted low
SCLx
PEN
BCLxIF
P
‘0’
SSPxIF
‘0’
FIGURE 16-32:
BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG
TBRG
TBRG
SDAx
Assert SDAx
SCLx
SCLx goes low before SDAx goes high,
set BCLxIF
PEN
BCLxIF
P
‘0’
SSPxIF
‘0’
© 2009 Microchip Technology Inc.
DS39682E-page 191
PIC18F45J10 FAMILY
TABLE 16-4:
Name
REGISTERS ASSOCIATED WITH I2C™ OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on Page
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
(1)
49
PSPIE
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
IPR1
(1)
PSPIP
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
49
—
—
—
—
—
49
—
—
—
—
—
49
PIR3
SSP2IF
BCL2IF
—
PIE3
SSP2IE
BCL2IE
—
IPR3
SSP2IP
BCL2IP
—
—
—
—
—
—
49
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
50
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
TRISD(1)
50
SSP1BUF
MSSP1 Receive Buffer/Transmit Register
48
SSP1ADD
MSSP1 Address Register (I2C™ Slave mode).
MSSP1 Baud Rate Reload Register (I2C Master mode).
48
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
48
SSP1CON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
48
GCEN
ACKSTAT
ADMSK5(2)
ADMSK4(2)
ADMSK3(2)
ADMSK2(2)
ADMSK1(2)
SEN
48
SMP
CKE
D/A
P
S
R/W
UA
BF
SSP1STAT
48
SSP2BUF
MSSP2 Receive Buffer/Transmit Register
50
SSP2ADD
MSSP2 Address Register (I2C Slave mode).
MSSP2 Baud Rate Reload Register (I2C Master mode).
50
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
50
SSP2CON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
50
GCEN
ACKSTAT
ADMSK5(2)
ADMSK4(2)
ADMSK3(2)
ADMSK2(2)
ADMSK1(2)
SEN
48
SMP
CKE
D/A
P
S
R/W
UA
BF
50
SSP2STAT
Legend:
Note 1:
2:
— = unimplemented, read as ‘0’. Shaded cells are not used by the MSSP module in I2C™ mode.
These registers and/or bits are not implemented on 28-pin devices and should be read as ‘0’.
Alternate names and definitions for these bits when the MSSP module is operating in I2C Slave mode. See
Section 16.4.3.2 “Address Masking” for details.
DS39682E-page 192
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.0
ENHANCED UNIVERSAL
SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (EUSART)
The Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART) module is one of the
two serial I/O modules. (Generically, the USART is also
known as a Serial Communications Interface or SCI.)
The EUSART can be configured as a full-duplex,
asynchronous system that can communicate with
peripheral devices, such as CRT terminals and
personal computers. It can also be configured as a halfduplex synchronous system that can communicate
with peripheral devices, such as A/D or D/A integrated
circuits, serial EEPROMs, etc.
The Enhanced USART module implements additional
features, including automatic baud rate detection and
calibration, automatic wake-up on Sync Break reception and 12-bit Break character transmit. These make it
ideally suited for use in Local Interconnect Network
(LIN/J2602) bus systems.
The pins of the Enhanced USART are multiplexed
with PORTC. In order to configure RC6/TX/CK and
RC7/RX/DT as an EUSART:
• bit SPEN (RCSTA<7>) must be set (= 1)
• bit TRISC<7> must be set (= 1)
• bit TRISC<6> must be set (= 1)
Note:
The EUSART control will automatically
reconfigure the pin from input to output as
needed.
The operation of the Enhanced USART module is
controlled through three registers:
• Transmit Status and Control (TXSTA)
• Receive Status and Control (RCSTA)
• Baud Rate Control (BAUDCON)
These are detailed on the following pages in
Register 17-1, Register 17-2 and Register 17-3,
respectively.
The EUSART can be configured in the following
modes:
• Asynchronous (full duplex) with:
- Auto-wake-up on character reception
- Auto-baud calibration
- 12-bit Break character transmission
• Synchronous – Master (half duplex) with
selectable clock polarity
• Synchronous – Slave (half duplex) with selectable
clock polarity
© 2009 Microchip Technology Inc.
DS39682E-page 193
PIC18F45J10 FAMILY
REGISTER 17-1:
TXSTA: EUSART TRANSMIT STATUS AND CONTROL REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R-1
R/W-0
CSRC
TX9
TXEN(1)
SYNC
SENDB
BRGH
TRMT
TX9D
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
CSRC: Clock Source Select bit
Asynchronous mode:
Don’t care.
Synchronous mode:
1 = Master mode (clock generated internally from BRG)
0 = Slave mode (clock from external source)
bit 6
TX9: 9-Bit Transmit Enable bit
1 = Selects 9-bit transmission
0 = Selects 8-bit transmission
bit 5
TXEN: Transmit Enable bit(1)
1 = Transmit enabled
0 = Transmit disabled
bit 4
SYNC: EUSART Mode Select bit
1 = Synchronous mode
0 = Asynchronous mode
bit 3
SENDB: Send Break Character bit
Asynchronous mode:
1 = Send Sync Break on next transmission (cleared by hardware upon completion)
0 = Sync Break transmission completed
Synchronous mode:
Don’t care.
bit 2
BRGH: High Baud Rate Select bit
Asynchronous mode:
1 = High speed
0 = Low speed
Synchronous mode:
Unused in this mode.
bit 1
TRMT: Transmit Shift Register Status bit
1 = TSR empty
0 = TSR full
bit 0
TX9D: 9th Bit of Transmit Data
Can be address/data bit or a parity bit.
Note 1:
SREN/CREN overrides TXEN in Sync mode.
DS39682E-page 194
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 17-2:
RCSTA: EUSART RECEIVE STATUS AND CONTROL REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R-0
R-0
R-x
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SPEN: Serial Port Enable bit
1 = Serial port enabled (configures RX/DT and TX/CK pins as serial port pins)
0 = Serial port disabled (held in Reset)
bit 6
RX9: 9-Bit Receive Enable bit
1 = Selects 9-bit reception
0 = Selects 8-bit reception
bit 5
SREN: Single Receive Enable bit
Asynchronous mode:
Don’t care.
Synchronous mode – Master:
1 = Enables single receive
0 = Disables single receive
This bit is cleared after reception is complete.
Synchronous mode – Slave:
Don’t care.
bit 4
CREN: Continuous Receive Enable bit
Asynchronous mode:
1 = Enables receiver
0 = Disables receiver
Synchronous mode:
1 = Enables continuous receive until enable bit, CREN, is cleared (CREN overrides SREN)
0 = Disables continuous receive
bit 3
ADDEN: Address Detect Enable bit
Asynchronous mode 9-bit (RX9 = 1):
1 = Enables address detection, enables interrupt and loads the receive buffer when RSR<8> is set
0 = Disables address detection, all bytes are received and ninth bit can be used as parity bit
Asynchronous mode 9-bit (RX9 = 0):
Don’t care.
bit 2
FERR: Framing Error bit
1 = Framing error (can be updated by reading RCREG register and receiving next valid byte)
0 = No framing error
bit 1
OERR: Overrun Error bit
1 = Overrun error (can be cleared by clearing bit, CREN)
0 = No overrun error
bit 0
RX9D: 9th Bit of Received Data
This can be address/data bit or a parity bit and must be calculated by user firmware.
© 2009 Microchip Technology Inc.
DS39682E-page 195
PIC18F45J10 FAMILY
REGISTER 17-3:
BAUDCON: BAUD RATE CONTROL REGISTER 1
R/W-0
R-1
U-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ABDOVF: Auto-Baud Acquisition Rollover Status bit
1 = A BRG rollover has occurred during Auto-Baud Rate Detect mode (must be cleared in software)
0 = No BRG rollover has occurred
bit 6
RCIDL: Receive Operation Idle Status bit
1 = Receive operation is Idle
0 = Receive operation is active
bit 5
Unimplemented: Read as ‘0’
bit 4
SCKP: Synchronous Clock Polarity Select bit
Asynchronous mode:
Unused in this mode.
Synchronous mode:
1 = Idle state for clock (CK) is a high level
0 = Idle state for clock (CK) is a low level
bit 3
BRG16: 16-Bit Baud Rate Register Enable bit
1 = 16-bit Baud Rate Generator – SPBRGH and SPBRG
0 = 8-bit Baud Rate Generator – SPBRG only (Compatible mode), SPBRGH value ignored
bit 2
Unimplemented: Read as ‘0’
bit 1
WUE: Wake-up Enable bit
Asynchronous mode:
1 = EUSART will continue to sample the RX pin – interrupt generated on falling edge; bit cleared in
hardware on following rising edge
0 = RX pin not monitored or rising edge detected
Synchronous mode:
Unused in this mode.
bit 0
ABDEN: Auto-Baud Detect Enable bit
Asynchronous mode:
1 = Enable baud rate measurement on the next character. Requires reception of a Sync field (55h);
cleared in hardware upon completion.
0 = Baud rate measurement disabled or completed
Synchronous mode:
Unused in this mode.
DS39682E-page 196
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.1
Baud Rate Generator (BRG)
The BRG is a dedicated 8-bit or 16-bit generator that
supports both the Asynchronous and Synchronous
modes of the EUSART. By default, the BRG operates
in 8-bit mode; setting the BRG16 bit (BAUDCON<3>)
selects 16-bit mode.
The SPBRGH:SPBRG register pair controls the period
of a free-running timer. In Asynchronous mode, bits,
BRGH (TXSTA<2>) and BRG16 (BAUDCON<3>), also
control the baud rate. In Synchronous mode, BRGH is
ignored. Table 17-1 shows the formula for computation
of the baud rate for different EUSART modes which
only apply in Master mode (internally generated clock).
Given the desired baud rate and FOSC, the nearest
integer value for the SPBRGH:SPBRG registers can be
calculated using the formulas in Table 17-1. From this,
the error in baud rate can be determined. An example
calculation is shown in Example 17-1. Typical baud
rates and error values for the various Asynchronous
modes are shown in Table 17-2. It may be
TABLE 17-1:
advantageous to use the high baud rate (BRGH = 1) or
the 16-bit BRG to reduce the baud rate error, or
achieve a slow baud rate for a fast oscillator frequency.
Writing a new value to the SPBRGH:SPBRG registers
causes the BRG timer to be reset (or cleared). This
ensures the BRG does not wait for a timer overflow
before outputting the new baud rate.
17.1.1
OPERATION IN POWER-MANAGED
MODES
The device clock is used to generate the desired baud
rate. When one of the power-managed modes is
entered, the new clock source may be operating at a
different frequency. This may require an adjustment to
the value in the SPBRG register pair.
17.1.2
SAMPLING
The data on the RX pin is sampled three times by a
majority detect circuit to determine if a high or a low
level is present at the RX pin.
BAUD RATE FORMULAS
Configuration Bits
BRG/EUSART Mode
Baud Rate Formula
8-bit/Asynchronous
FOSC/[64 (n + 1)]
SYNC
BRG16
BRGH
0
0
0
0
0
1
8-bit/Asynchronous
0
1
0
16-bit/Asynchronous
0
1
1
16-bit/Asynchronous
1
0
x
8-bit/Synchronous
1
1
x
16-bit/Synchronous
FOSC/[16 (n + 1)]
FOSC/[4 (n + 1)]
Legend: x = Don’t care, n = value of SPBRGH:SPBRG register pair
© 2009 Microchip Technology Inc.
DS39682E-page 197
PIC18F45J10 FAMILY
EXAMPLE 17-1:
CALCULATING BAUD RATE ERROR
For a device with FOSC of 16 MHz, desired baud rate of 9600, Asynchronous mode, 8-bit BRG:
Desired Baud Rate
= FOSC/(64 ([SPBRGH:SPBRG] + 1))
Solving for SPBRGH:SPBRG:
X
= ((FOSC/Desired Baud Rate)/64) – 1
= ((16000000/9600)/64) – 1
= [25.042] = 25
Calculated Baud Rate = 16000000/(64 (25 + 1))
= 9615
Error
= (Calculated Baud Rate – Desired Baud Rate)/Desired Baud Rate
= (9615 – 9600)/9600 = 0.16%
TABLE 17-2:
REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset Values
on page
TXSTA
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
Name
BAUDCON ABDOVF
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the BRG.
DS39682E-page 198
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 17-3:
BAUD RATES FOR ASYNCHRONOUS MODES
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
(K)
FOSC = 40.000 MHz
FOSC = 20.000 MHz
Actual
Rate
(K)
FOSC = 10.000 MHz
Actual
Rate
(K)
FOSC = 8.000 MHz
Actual
Rate
(K)
Actual
Rate
(K)
%
Error
0.3
—
—
—
—
—
—
—
—
—
—
—
—
1.2
—
—
—
1.221
1.73
255
1.202
0.16
129
1.201
-0.16
103
2.4
2.441
1.73
255
2.404
0.16
129
2.404
0.16
64
2.403
-0.16
51
9.6
9.615
0.16
64
9.766
1.73
31
9.766
1.73
15
9.615
-0.16
12
—
SPBRG
value
(decimal)
%
Error
SPBRG
value
(decimal)
%
Error
SPBRG
value
(decimal)
%
Error
SPBRG
value
(decimal)
19.2
19.531
1.73
31
19.531
1.73
15
19.531
1.73
7
—
—
57.6
56.818
-1.36
10
62.500
8.51
4
52.083
-9.58
2
—
—
—
115.2
125.000
8.51
4
104.167
-9.58
2
78.125
-32.18
1
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
(K)
FOSC = 4.000 MHz
FOSC = 2.000 MHz
FOSC = 1.000 MHz
(decimal)
Actual
Rate
(K)
0.16
207
0.300
-0.16
103
0.300
-0.16
51
0.16
51
1.201
-0.16
25
1.201
-0.16
12
2.404
0.16
25
2.403
-0.16
12
—
—
—
9.6
8.929
-6.99
6
—
—
—
—
—
—
19.2
20.833
8.51
2
—
—
—
—
—
—
Actual
Rate
(K)
%
Error
0.3
0.300
1.2
1.202
2.4
SPBRG
value
%
Error
(decimal)
Actual
Rate
(K)
%
Error
SPBRG
value
SPBRG
value
(decimal)
57.6
62.500
8.51
0
—
—
—
—
—
—
115.2
62.500
-45.75
0
—
—
—
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
(K)
FOSC = 40.000 MHz
FOSC = 20.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
—
—
—
—
—
—
—
—
—
Actual
Rate
(K)
%
Error
0.3
—
1.2
—
2.4
—
SPBRG
value
FOSC = 10.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
—
—
—
—
—
—
—
—
2.441
SPBRG
value
FOSC = 8.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
—
—
—
—
—
—
—
—
—
1.73
255
2.403
-0.16
207
SPBRG
value
SPBRG
value
(decimal)
—
9.6
9.766
1.73
255
9.615
0.16
129
9.615
0.16
64
9.615
-0.16
51
19.2
19.231
0.16
129
19.231
0.16
64
19.531
1.73
31
19.230
-0.16
25
57.6
58.140
0.94
42
56.818
-1.36
21
56.818
-1.36
10
55.555
3.55
8
115.2
113.636
-1.36
21
113.636
-1.36
10
125.000
8.51
4
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
(K)
FOSC = 4.000 MHz
FOSC = 2.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
—
0.16
—
207
—
1.201
2.404
0.16
103
9.6
9.615
0.16
19.2
19.231
0.16
Actual
Rate
(K)
%
Error
0.3
1.2
—
1.202
2.4
FOSC = 1.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
—
-0.16
—
103
0.300
1.201
-0.16
-0.16
207
51
2.403
-0.16
51
2.403
-0.16
25
25
9.615
-0.16
12
—
—
—
12
—
—
—
—
—
—
SPBRG
value
SPBRG
value
SPBRG
value
(decimal)
57.6
62.500
8.51
3
—
—
—
—
—
—
115.2
125.000
8.51
1
—
—
—
—
—
—
© 2009 Microchip Technology Inc.
DS39682E-page 199
PIC18F45J10 FAMILY
TABLE 17-3:
BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
(K)
FOSC = 40.000 MHz
FOSC = 20.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.00
0.02
8332
2082
0.300
1.200
0.06
1040
2.399
Actual
Rate
(K)
%
Error
0.3
1.2
0.300
1.200
2.4
2.402
SPBRG
value
FOSC = 10.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.02
-0.03
4165
1041
0.300
1.200
-0.03
520
2.404
SPBRG
value
FOSC = 8.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.02
-0.03
2082
520
0.300
1.201
-0.04
-0.16
1665
415
0.16
259
2.403
-0.16
207
SPBRG
value
SPBRG
value
(decimal)
9.6
9.615
0.16
259
9.615
0.16
129
9.615
0.16
64
9.615
-0.16
51
19.2
19.231
0.16
129
19.231
0.16
64
19.531
1.73
31
19.230
-0.16
25
57.6
58.140
0.94
42
56.818
-1.36
21
56.818
-1.36
10
55.555
3.55
8
115.2
113.636
-1.36
21
113.636
-1.36
10
125.000
8.51
4
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
(K)
0.3
FOSC
= 4.000 MHz
Actual
Rate
(K)
%
Error
0.300
0.04
FOSC = 2.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
832
0.300
-0.16
SPBRG
value
FOSC = 1.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
415
0.300
-0.16
SPBRG
value
SPBRG
value
(decimal)
207
1.2
1.202
0.16
207
1.201
-0.16
103
1.201
-0.16
51
2.4
2.404
0.16
103
2.403
-0.16
51
2.403
-0.16
25
9.6
9.615
0.16
25
9.615
-0.16
12
—
—
—
19.2
19.231
0.16
12
—
—
—
—
—
—
57.6
62.500
8.51
3
—
—
—
—
—
—
115.2
125.000
8.51
1
—
—
—
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
(K)
FOSC = 40.000 MHz
FOSC = 20.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.00
33332
0.300
0.00
8332
1.200
2.400
0.02
4165
9.6
9.606
0.06
19.2
19.193
57.6
57.803
115.2
114.943
FOSC = 10.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.00
16665
0.300
0.02
4165
1.200
2.400
0.02
2082
1040
9.596
-0.03
-0.03
520
19.231
0.35
172
57.471
-0.22
86
116.279
0.94
Actual
Rate
(K)
%
Error
0.3
0.300
1.2
1.200
2.4
SPBRG
value
FOSC = 8.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
0.00
8332
0.300
-0.01
6665
0.02
2082
1.200
-0.04
1665
2.402
0.06
1040
2.400
-0.04
832
520
9.615
0.16
259
9.615
-0.16
207
0.16
259
19.231
0.16
129
19.230
-0.16
103
-0.22
86
58.140
0.94
42
57.142
0.79
34
42
113.636
-1.36
21
117.647
-2.12
16
SPBRG
value
SPBRG
value
SPBRG
value
(decimal)
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
(K)
FOSC = 4.000 MHz
Actual
Rate
(K)
%
Error
0.3
0.300
0.01
1.2
1.200
0.04
FOSC = 2.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
3332
0.300
-0.04
832
1.201
SPBRG
value
FOSC = 1.000 MHz
(decimal)
Actual
Rate
(K)
%
Error
1665
0.300
-0.04
832
-0.16
415
1.201
-0.16
207
SPBRG
value
SPBRG
value
(decimal)
2.4
2.404
0.16
415
2.403
-0.16
207
2.403
-0.16
103
9.6
9.615
0.16
103
9.615
-0.16
51
9.615
-0.16
25
19.2
19.231
0.16
51
19.230
-0.16
25
19.230
-0.16
12
57.6
58.824
2.12
16
55.555
3.55
8
—
—
—
115.2
111.111
-3.55
8
—
—
—
—
—
—
DS39682E-page 200
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.1.3
AUTO-BAUD RATE DETECT
The Enhanced USART module supports the automatic
detection and calibration of baud rate. This feature is
active only in Asynchronous mode and while the WUE
bit is clear.
Note 1: If the WUE bit is set with the ABDEN bit,
Auto-Baud Rate Detection will occur on
the byte following the Break character.
2: It is up to the user to determine that the
incoming character baud rate is within the
range of the selected BRG clock source.
Some combinations of oscillator frequency
and EUSART baud rates are not possible
due to bit error rates. Overall system timing and communication baud rates must
be taken into consideration when using the
Auto-Baud Rate Detection feature.
The automatic baud rate measurement sequence
(Figure 17-1) begins whenever a Start bit is received
and the ABDEN bit is set. The calculation is
self-averaging.
In the Auto-Baud Rate Detect (ABD) mode, the clock to
the BRG is reversed. Rather than the BRG clocking the
incoming RX signal, the RX signal is timing the BRG. In
ABD mode, the internal Baud Rate Generator is used
as a counter to time the bit period of the incoming serial
byte stream.
Once the ABDEN bit is set, the state machine will clear
the BRG and look for a Start bit. The Auto-Baud Rate
Detect must receive a byte with the value 55h (ASCII
“U”, which is also the LIN/J2602 bus Sync character) in
order to calculate the proper bit rate. The measurement
is taken over both a low and a high bit time in order to
minimize any effects caused by asymmetry of the incoming signal. After a Start bit, the SPBRG begins counting
up, using the preselected clock source on the first rising
edge of RX. After eight bits on the RX pin or the fifth rising edge, an accumulated value totalling the proper BRG
period is left in the SPBRGH:SPBRG register pair. Once
the 5th edge is seen (this should correspond to the Stop
bit), the ABDEN bit is automatically cleared.
If a rollover of the BRG occurs (an overflow from FFFFh
to 0000h), the event is trapped by the ABDOVF status
bit (BAUDCON<7>). It is set in hardware by BRG rollovers and can be set or cleared by the user in software.
ABD mode remains active after rollover events and the
ABDEN bit remains set (Figure 17-2).
TABLE 17-4:
BRG COUNTER
CLOCK RATES
BRG16
BRGH
BRG Counter Clock
0
0
FOSC/512
0
1
FOSC/128
1
0
FOSC/128
1
FOSC/32
1
Note:
During the ABD sequence, SPBRG and
SPBRGH are both used as a 16-bit counter,
independent of BRG16 setting.
17.1.3.1
ABD and EUSART Transmission
Since the BRG clock is reversed during ABD acquisition, the EUSART transmitter cannot be used during
ABD. This means that whenever the ABDEN bit is set,
TXREG cannot be written to. Users should also ensure
that ABDEN does not become set during a transmit
sequence. Failing to do this may result in unpredictable
EUSART operation.
While calibrating the baud rate period, the BRG registers are clocked at 1/8th the preconfigured clock rate.
Note that the BRG clock will be configured by the
BRG16 and BRGH bits. Independent of the BRG16 bit
setting, both the SPBRG and SPBRGH will be used as
a 16-bit counter. This allows the user to verify that no
carry occurred for 8-bit modes by checking for 00h in
the SPBRGH register. Refer to Table 17-4 for counter
clock rates to the BRG.
While the ABD sequence takes place, the EUSART
state machine is held in Idle. The RCIF interrupt is set
once the fifth rising edge on RX is detected. The value
in the RCREG needs to be read to clear the RCIF
interrupt. The contents of RCREG should be discarded.
© 2009 Microchip Technology Inc.
DS39682E-page 201
PIC18F45J10 FAMILY
FIGURE 17-1:
BRG Value
AUTOMATIC BAUD RATE CALCULATION
XXXXh
RX pin
0000h
001Ch
Start
Edge #1
Bit 1
Bit 0
Edge #2
Bit 3
Bit 2
Edge #3
Bit 5
Bit 4
Edge #4
Bit 7
Bit 6
Edge #5
Stop Bit
BRG Clock
Auto-Cleared
Set by User
ABDEN bit
RCIF bit
(Interrupt)
Read
RCREG
SPBRG
XXXXh
1Ch
SPBRGH
XXXXh
00h
Note: The ABD sequence requires the EUSART module to be configured in Asynchronous mode and WUE = 0.
FIGURE 17-2:
BRG OVERFLOW SEQUENCE
BRG Clock
ABDEN bit
RX pin
Start
Bit 0
ABDOVF bit
FFFFh
BRG Value
DS39682E-page 202
XXXXh
0000h
0000h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.2
Once the TXREG register transfers the data to the TSR
register (occurs in one TCY), the TXREG register is empty
and the TXIF flag bit (PIR1<4>) is set. This interrupt can
be enabled or disabled by setting or clearing the interrupt
enable bit, TXIE (PIE1<4>). TXIF will be set regardless of
the state of TXIE; it cannot be cleared in software. TXIF
is also not cleared immediately upon loading TXREG, but
becomes valid in the second instruction cycle following
the load instruction. Polling TXIF immediately following a
load of TXREG will return invalid results.
EUSART Asynchronous Mode
The Asynchronous mode of operation is selected by
clearing the SYNC bit (TXSTA<4>). In this mode, the
EUSART uses standard Non-Return-to-Zero (NRZ) format (one Start bit, eight or nine data bits and one Stop
bit). The most common data format is 8 bits. An on-chip,
dedicated 8-bit/16-bit Baud Rate Generator can be used
to derive standard baud rate frequencies from the
oscillator.
The EUSART transmits and receives the LSb first. The
EUSART’s transmitter and receiver are functionally
independent but use the same data format and baud
rate. The Baud Rate Generator produces a clock, either
x16 or x64 of the bit shift rate depending on the BRGH
and BRG16 bits (TXSTA<2> and BAUDCON<3>). Parity
is not supported by the hardware but can be
implemented in software and stored as the 9th data bit.
While TXIF indicates the status of the TXREG register,
another bit, TRMT (TXSTA<1>), shows the status of
the TSR register. TRMT is a read-only bit which is set
when the TSR register is empty. No interrupt logic is
tied to this bit so the user has to poll this bit in order to
determine if the TSR register is empty.
Note 1: The TSR register is not mapped in data
memory so it is not available to the user.
When operating in Asynchronous mode, the EUSART
module consists of the following important elements:
•
•
•
•
•
•
•
2: Flag bit TXIF is set when enable bit TXEN
is set.
Baud Rate Generator
Sampling Circuit
Asynchronous Transmitter
Asynchronous Receiver
Auto-Wake-up on Sync Break Character
12-Bit Break Character Transmit
Auto-Baud Rate Detection
17.2.1
To set up an Asynchronous Transmission:
1.
2.
EUSART ASYNCHRONOUS
TRANSMITTER
3.
4.
The EUSART transmitter block diagram is shown in
Figure 17-3. The heart of the transmitter is the Transmit
(Serial) Shift Register (TSR). The Shift register obtains
its data from the Read/Write Transmit Buffer register,
TXREG. The TXREG register is loaded with data in
software. The TSR register is not loaded until the Stop
bit has been transmitted from the previous load. As
soon as the Stop bit is transmitted, the TSR is loaded
with new data from the TXREG register (if available).
FIGURE 17-3:
5.
6.
7.
8.
Initialize the SPBRGH:SPBRG registers for the
appropriate baud rate. Set or clear the BRGH
and BRG16 bits, as required, to achieve the
desired baud rate.
Enable the asynchronous serial port by clearing
bit, SYNC, and setting bit, SPEN.
If interrupts are desired, set enable bit, TXIE.
If 9-bit transmission is desired, set transmit bit,
TX9. Can be used as address/data bit.
Enable the transmission by setting bit, TXEN,
which will also set bit, TXIF.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
Load data to the TXREG register (starts
transmission).
If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
EUSART TRANSMIT BLOCK DIAGRAM
Data Bus
TXIF
TXREG Register
TXIE
8
MSb
(8)
LSb
• • •
Pin Buffer
and Control
0
TSR Register
TX pin
Interrupt
TXEN
Baud Rate CLK
TRMT
BRG16
SPBRGH
SPBRG
Baud Rate Generator
© 2009 Microchip Technology Inc.
SPEN
TX9
TX9D
DS39682E-page 203
PIC18F45J10 FAMILY
FIGURE 17-4:
ASYNCHRONOUS TRANSMISSION
Write to TXREG
Word 1
BRG Output
(Shift Clock)
TX (pin)
Start bit
bit 0
bit 1
bit 7/8
Stop bit
Word 1
TXIF bit
(Transmit Buffer
Reg. Empty Flag)
1 TCY
Word 1
Transmit Shift Reg
TRMT bit
(Transmit Shift
Reg. Empty Flag)
FIGURE 17-5:
ASYNCHRONOUS TRANSMISSION (BACK TO BACK)
Write to TXREG
Word 2
Word 1
BRG Output
(Shift Clock)
TX (pin)
Start bit
bit 0
bit 1
1 TCY
TXIF bit
(Interrupt Reg. Flag)
bit 7/8
Stop bit
Start bit
bit 0
Word 2
Word 1
1 TCY
Word 1
Transmit Shift Reg.
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Word 2
Transmit Shift Reg.
Note: This timing diagram shows two consecutive transmissions.
TABLE 17-5:
Name
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCSTA
TXREG
EUSART Transmit Register
49
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
BAUDCON
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
TXSTA
Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous transmission.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 204
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.2.2
EUSART ASYNCHRONOUS
RECEIVER
17.2.3
The receiver block diagram is shown in Figure 17-6.
The data is received on the RX pin and drives the data
recovery block. The data recovery block is actually a
high-speed shifter operating at x16 times the baud rate,
whereas the main receive serial shifter operates at the
bit rate or at FOSC. This mode would typically be used
in RS-232 systems.
This mode would typically be used in RS-485 systems.
To set up an Asynchronous Reception with Address
Detect Enable:
1.
Initialize the SPBRGH:SPBRG registers for the
appropriate baud rate. Set or clear the BRGH
and BRG16 bits, as required, to achieve the
desired baud rate.
2. Enable the asynchronous serial port by clearing
the SYNC bit and setting the SPEN bit.
3. If interrupts are required, set the RCEN bit and
select the desired priority level with the RCIP bit.
4. Set the RX9 bit to enable 9-bit reception.
5. Set the ADDEN bit to enable address detect.
6. Enable reception by setting the CREN bit.
7. The RCIF bit will be set when reception is
complete. The interrupt will be Acknowledged if
the RCIE and GIE bits are set.
8. Read the RCSTA register to determine if any
error occurred during reception, as well as read
bit 9 of data (if applicable).
9. Read RCREG to determine if the device is being
addressed.
10. If any error occurred, clear the CREN bit.
11. If the device has been addressed, clear the
ADDEN bit to allow all received data into the
receive buffer and interrupt the CPU.
To set up an Asynchronous Reception:
1.
Initialize the SPBRGH:SPBRG registers for the
appropriate baud rate. Set or clear the BRGH
and BRG16 bits, as required, to achieve the
desired baud rate.
2. Enable the asynchronous serial port by clearing
bit, SYNC, and setting bit, SPEN.
3. If interrupts are desired, set enable bit, RCIE.
4. If 9-bit reception is desired, set bit, RX9.
5. Enable the reception by setting bit, CREN.
6. Flag bit, RCIF, will be set when reception is
complete and an interrupt will be generated if
enable bit, RCIE, was set.
7. Read the RCSTA register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
8. Read the 8-bit received data by reading the
RCREG register.
9. If any error occurred, clear the error by clearing
enable bit, CREN.
10. If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
FIGURE 17-6:
SETTING UP 9-BIT MODE WITH
ADDRESS DETECT
EUSART RECEIVE BLOCK DIAGRAM
CREN
OERR
FERR
x64 Baud Rate CLK
BRG16
SPBRGH
SPBRG
Baud Rate Generator
÷ 64
or
÷ 16
or
÷4
RSR Register
MSb
Stop
(8)
7
• • •
1
LSb
0
Start
RX9
Pin Buffer
and Control
Data
Recovery
RX
RX9D
RCREG Register
FIFO
SPEN
8
Interrupt
RCIF
Data Bus
RCIE
© 2009 Microchip Technology Inc.
DS39682E-page 205
PIC18F45J10 FAMILY
FIGURE 17-7:
ASYNCHRONOUS RECEPTION
Start
bit
RX (pin)
bit 0
bit 7/8 Stop
bit
bit 1
Rcv Shift Reg
Rcv Buffer Reg
Start
bit
bit 0
Stop
bit
Start
bit
bit 7/8
Stop
bit
Word 2
RCREG
Word 1
RCREG
Read Rcv
Buffer Reg
RCREG
bit 7/8
RCIF
(Interrupt Flag)
OERR bit
CREN
Note:
This timing diagram shows three words appearing on the RX input. The RCREG (receive buffer) is read after the third word causing
the OERR (Overrun) bit to be set.
TABLE 17-6:
Name
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Bit 7
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
Bit 6
INTCON
GIE/GIEH PEIE/GIEL
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCSTA
RCREG
EUSART Receive Register
49
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
BAUDCON
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
TXSTA
49
49
Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous reception.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
17.2.4
AUTO-WAKE-UP ON SYNC BREAK
CHARACTER
During Sleep mode, all clocks to the EUSART are
suspended. Because of this, the Baud Rate Generator
is inactive and a proper byte reception cannot be performed. The auto-wake-up feature allows the controller
to wake-up due to activity on the RX/DT line while the
EUSART is operating in Asynchronous mode.
The auto-wake-up feature is enabled by setting the
WUE bit (BAUDCON<1>). Once set, the typical receive
sequence on RX/DT is disabled and the EUSART
remains in an Idle state, monitoring for a wake-up event
independent of the CPU mode. A wake-up event consists of a high-to-low transition on the RX/DT line. (This
coincides with the start of a Sync Break or a Wake-up
Signal character for the LIN/J2602 support protocol.)
DS39682E-page 206
Following a wake-up event, the module generates an
RCIF interrupt. The interrupt is generated synchronously to the Q clocks in normal operating modes
(Figure 17-8) and asynchronously, if the device is in
Sleep mode (Figure 17-9). The interrupt condition is
cleared by reading the RCREG register.
The WUE bit is automatically cleared once a low-tohigh transition is observed on the RX line following the
wake-up event. At this point, the EUSART module is in
Idle mode and returns to normal operation. This signals
to the user that the Sync Break event is over.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.2.4.1
Special Considerations Using
Auto-Wake-up
17.2.4.2
Since auto-wake-up functions by sensing rising edge
transitions on RX/DT, information with any state
changes before the Stop bit may signal a false End-OfCharacter (EOC) and cause data or framing errors. To
work properly, therefore, the initial character in the
transmission must be all ‘0’s. This can be 00h (8 bytes)
for standard RS-232 devices or 000h (12 bits) for LIN
bus.
The timing of WUE and RCIF events may cause some
confusion when it comes to determining the validity of
received data. As noted, setting the WUE bit places the
EUSART in an Idle mode. The wake-up event causes a
receive interrupt by setting the RCIF bit. The WUE bit is
cleared after this when a rising edge is seen on RX/DT.
The interrupt condition is then cleared by reading the
RCREG register. Ordinarily, the data in RCREG will be
dummy data and should be discarded.
Oscillator start-up time must also be considered,
especially in applications using oscillators with longer
start-up intervals (i.e., HS mode). The Sync Break (or
Wake-up Signal) character must be of sufficient length
and be followed by a sufficient interval to allow enough
time for the selected oscillator to start and provide
proper initialization of the EUSART.
FIGURE 17-8:
Special Considerations Using
the WUE Bit
The fact that the WUE bit has been cleared (or is still
set) and the RCIF flag is set should not be used as an
indicator of the integrity of the data in RCREG. Users
should consider implementing a parallel method in
firmware to verify received data integrity.
To assure that no actual data is lost, check the RCIDL
bit to verify that a receive operation is not in process. If
a receive operation is not occurring, the WUE bit may
then be set just prior to entering the Sleep mode.
AUTO-WAKE-UP BIT (WUE) TIMINGS DURING NORMAL OPERATION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
Bit set by user
Auto-Cleared
WUE bit(1)
RX/DT Line
RCIF
Note 1:
Cleared due to user read of RCREG
The EUSART remains in Idle while the WUE bit is set.
FIGURE 17-9:
AUTO-WAKE-UP BIT (WUE) TIMINGS DURING SLEEP
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
Q1
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Bit set by user
Auto-Cleared
WUE bit(2)
RX/DT Line
Note 1
RCIF
Sleep Command Executed
Note 1:
2:
Sleep Ends
Cleared due to user read of RCREG
If the wake-up event requires long oscillator warm-up time, the auto-clear of the WUE bit can occur before the oscillator is ready. This
sequence should not depend on the presence of Q clocks.
The EUSART remains in Idle while the WUE bit is set.
© 2009 Microchip Technology Inc.
DS39682E-page 207
PIC18F45J10 FAMILY
17.2.5
BREAK CHARACTER SEQUENCE
The EUSART module has the capability of sending the
special Break character sequences that are required by
the LIN/J2602 support standard. The Break character
transmit consists of a Start bit, followed by twelve ‘0’
bits and a Stop bit. The frame Break character is sent
whenever the SENDB and TXEN bits (TXSTA<3> and
TXSTA<5>) are set while the Transmit Shift register is
loaded with data. Note that the value of data written to
TXREG will be ignored and all ‘0’s will be transmitted.
The SENDB bit is automatically reset by hardware after
the corresponding Stop bit is sent. This allows the user
to preload the transmit FIFO with the next transmit byte
following the Break character (typically, the Sync
character in the LIN/J2602 support).
Note that the data value written to the TXREG for the
Break character is ignored. The write simply serves the
purpose of initiating the proper sequence.
The TRMT bit indicates when the transmit operation is
active or Idle, just as it does during normal transmission. See Figure 17-10 for the timing of the Break
character sequence.
17.2.5.1
Break and Sync Transmit Sequence
The following sequence will send a message frame
header made up of a Break, followed by an Auto-Baud
Sync byte. This sequence is typical of a LIN bus
master.
FIGURE 17-10:
Write to TXREG
1.
2.
3.
4.
5.
Configure the EUSART for the desired mode.
Set the TXEN and SENDB bits to set up the
Break character.
Load the TXREG with a dummy character to
initiate transmission (the value is ignored).
Write ‘55h’ to TXREG to load the Sync character
into the transmit FIFO buffer.
After the Break has been sent, the SENDB bit is
reset by hardware. The Sync character now
transmits in the preconfigured mode.
When the TXREG becomes empty, as indicated by the
TXIF, the next data byte can be written to TXREG.
17.2.6
RECEIVING A BREAK CHARACTER
The Enhanced USART module can receive a Break
character in two ways.
The first method forces configuration of the baud rate
at a frequency of 9/13 the typical speed. This allows for
the Stop bit transition to be at the correct sampling location (13 bits for Break versus Start bit and 8 data bits for
typical data).
The second method uses the auto-wake-up feature
described in Section 17.2.4 “Auto-Wake-up on Sync
Break Character”. By enabling this feature, the
EUSART will sample the next two transitions on RX/DT,
cause an RCIF interrupt and receive the next data byte
followed by another interrupt.
Note that following a Break character, the user will
typically want to enable the Auto-Baud Rate Detect
feature. For both methods, the user can set the ABD bit
once the TXIF interrupt is observed.
SEND BREAK CHARACTER SEQUENCE
Dummy Write
BRG Output
(Shift Clock)
TX (pin)
Start Bit
Bit 0
Bit 1
Bit 11
Stop Bit
Break
TXIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
SENDB sampled here
Auto-Cleared
SENDB
(Transmit Shift
Reg. Empty Flag)
DS39682E-page 208
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.3
Once the TXREG register transfers the data to the TSR
register (occurs in one TCY), the TXREG is empty and
the TXIF flag bit (PIR1<4>) is set. The interrupt can be
enabled or disabled by setting or clearing the interrupt
enable bit, TXIE (PIE1<4>). TXIF is set regardless of
the state of enable bit TXIE; it cannot be cleared in
software. It will reset only when new data is loaded into
the TXREG register.
EUSART Synchronous
Master Mode
The Synchronous Master mode is entered by setting
the CSRC bit (TXSTA<7>). In this mode, the data is
transmitted in a half-duplex manner (i.e., transmission
and reception do not occur at the same time). When
transmitting data, the reception is inhibited and vice
versa. Synchronous mode is entered by setting bit
SYNC (TXSTA<4>). In addition, enable bit SPEN
(RCSTA<7>) is set in order to configure the TX and RX
pins to CK (clock) and DT (data) lines, respectively.
While flag bit TXIF indicates the status of the TXREG
register, another bit, TRMT (TXSTA<1>), shows the
status of the TSR register. TRMT is a read-only bit which
is set when the TSR is empty. No interrupt logic is tied to
this bit so the user has to poll this bit in order to determine if the TSR register is empty. The TSR is not
mapped in data memory so it is not available to the user.
The Master mode indicates that the processor transmits the master clock on the CK line. Clock polarity is
selected with the SCKP bit (BAUDCON<4>). Setting
SCKP sets the Idle state on CK as high, while clearing
the bit sets the Idle state as low. This option is provided
to support Microwire devices with this module.
17.3.1
To set up a Synchronous Master Transmission:
1.
EUSART SYNCHRONOUS MASTER
TRANSMISSION
2.
The EUSART transmitter block diagram is shown in
Figure 17-3. The heart of the transmitter is the Transmit
(Serial) Shift Register (TSR). The Shift register obtains
its data from the Read/Write Transmit Buffer register,
TXREG. The TXREG register is loaded with data in
software. The TSR register is not loaded until the last
bit has been transmitted from the previous load. As
soon as the last bit is transmitted, the TSR is loaded
with new data from the TXREG (if available).
FIGURE 17-11:
3.
4.
5.
6.
7.
8.
Initialize the SPBRGH:SPBRG registers for the
appropriate baud rate. Set or clear the BRG16
bit, as required, to achieve the desired baud rate.
Enable the synchronous master serial port by
setting bits, SYNC, SPEN and CSRC.
If interrupts are desired, set enable bit, TXIE.
If 9-bit transmission is desired, set bit, TX9.
Enable the transmission by setting bit, TXEN.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
Start transmission by loading data to the TXREG
register.
If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
SYNCHRONOUS TRANSMISSION
Q1 Q2 Q3Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT
bit 0
bit 1
bit 2
Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
bit 7
Word 1
bit 0
bit 1
bit 7
Word 2
RC6/TX/CK pin
(SCKP = 0)
RC6/TX/CK pin
(SCKP = 1)
Write to
TXREG Reg
Write Word 1
Write Word 2
TXIF bit
(Interrupt Flag)
TRMT bit
TXEN bit
Note:
‘1’
‘1’
Sync Master mode, SPBRG = 0, continuous transmission of two 8-bit words.
© 2009 Microchip Technology Inc.
DS39682E-page 209
PIC18F45J10 FAMILY
FIGURE 17-12:
SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RC7/RX/DT pin
bit 0
bit 1
bit 2
bit 6
bit 7
RC6/TX/CK pin
Write to
TXREG reg
TXIF bit
TRMT bit
TXEN bit
TABLE 17-7:
Name
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCSTA
TXREG
TXSTA
BAUDCON
EUSART Transmit Register
49
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master transmission.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 210
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.3.2
EUSART SYNCHRONOUS
MASTER RECEPTION
3.
4.
5.
6.
Ensure bits, CREN and SREN, are clear.
If interrupts are desired, set enable bit, RCIE.
If 9-bit reception is desired, set bit, RX9.
If a single reception is required, set bit, SREN.
For continuous reception, set bit, CREN.
7. Interrupt flag bit, RCIF, will be set when reception
is complete and an interrupt will be generated if
the enable bit, RCIE, was set.
8. Read the RCSTA register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
9. Read the 8-bit received data by reading the
RCREG register.
10. If any error occurred, clear the error by clearing
bit, CREN.
11. If using interrupts, ensure that the GIE and PEIE bits
in the INTCON register (INTCON<7:6>) are set.
Once Synchronous mode is selected, reception is
enabled by setting either the Single Receive Enable bit,
SREN (RCSTA<5>), or the Continuous Receive
Enable bit, CREN (RCSTA<4>). Data is sampled on the
RX pin on the falling edge of the clock.
If enable bit SREN is set, only a single word is received.
If enable bit CREN is set, the reception is continuous
until CREN is cleared. If both bits are set, then CREN
takes precedence.
To set up a Synchronous Master Reception:
1.
2.
Initialize the SPBRGH:SPBRG registers for the
appropriate baud rate. Set or clear the BRG16
bit, as required, to achieve the desired baud rate.
Enable the synchronous master serial port by
setting bits, SYNC, SPEN and CSRC.
FIGURE 17-13:
SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT
pin
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
bit 6
bit 7
RC6/TX/CK pin
(SCKP = 0)
RC6/TX/CK pin
(SCKP = 1)
Write to
bit SREN
SREN bit
CREN bit ‘0’
‘0’
RCIF bit
(Interrupt)
Read
RXREG
Note:
Timing diagram demonstrates Sync Master mode with bit SREN = 1 and bit BRGH = 0.
TABLE 17-8:
Name
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
RCSTA
RCREG
TXSTA
EUSART Receive Register
CSRC
BAUDCON ABDOVF
49
49
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master reception.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 211
PIC18F45J10 FAMILY
17.4
To set up a Synchronous Slave Transmission:
EUSART Synchronous
Slave Mode
1.
Synchronous Slave mode is entered by clearing bit,
CSRC (TXSTA<7>). This mode differs from the
Synchronous Master mode in that the shift clock is supplied externally at the CK pin (instead of being supplied
internally in Master mode). This allows the device to
transfer or receive data while in any low-power mode.
17.4.1
EUSART SYNCHRONOUS
SLAVE TRANSMISSION
2.
3.
4.
5.
6.
The operation of the Synchronous Master and Slave
modes is identical, except in the case of the Sleep
mode.
7.
8.
If two words are written to the TXREG and then the
SLEEP instruction is executed, the following will occur:
a)
b)
c)
d)
e)
Enable the synchronous slave serial port by
setting bits, SYNC and SPEN, and clearing bit,
CSRC.
Clear bits, CREN and SREN.
If interrupts are desired, set enable bit, TXIE.
If 9-bit transmission is desired, set bit, TX9.
Enable the transmission by setting enable bit,
TXEN.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit, TX9D.
Start transmission by loading data to the TXREG
register.
If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
The first word will immediately transfer to the
TSR register and transmit.
The second word will remain in the TXREG
register.
Flag bit, TXIF, will not be set.
When the first word has been shifted out of TSR,
the TXREG register will transfer the second
word to the TSR and flag bit, TXIF, will now be
set.
If enable bit, TXIE, is set, the interrupt will wake
the chip from Sleep. If the global interrupt is
enabled, the program will branch to the interrupt
vector.
TABLE 17-9:
Name
INTCON
REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Bit 7
Bit 6
Bit 5
GIE/GIEH PEIE/GIEL TMR0IE
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF
(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCSTA
TXREG
TXSTA
EUSART Transmit Register
49
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
BAUDCON
ABDOVF
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave transmission.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
DS39682E-page 212
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
17.4.2
EUSART SYNCHRONOUS SLAVE
RECEPTION
To set up a Synchronous Slave Reception:
1.
The operation of the Synchronous Master and Slave
modes is identical, except in the case of Sleep, or any
Idle mode and bit, SREN, which is a “don’t care” in
Slave mode.
If receive is enabled by setting the CREN bit prior to
entering Sleep or any Idle mode, then a word may be
received while in this low-power mode. Once the word
is received, the RSR register will transfer the data to the
RCREG register; if the RCIE enable bit is set, the interrupt generated will wake the chip from the low-power
mode. If the global interrupt is enabled, the program will
branch to the interrupt vector.
2.
3.
4.
5.
6.
7.
8.
9.
Enable the synchronous master serial port by
setting bits, SYNC and SPEN, and clearing bit,
CSRC.
If interrupts are desired, set enable bit, RCIE.
If 9-bit reception is desired, set bit, RX9.
To enable reception, set enable bit, CREN.
Flag bit, RCIF, will be set when reception is
complete. An interrupt will be generated if
enable bit, RCIE, was set.
Read the RCSTA register to get the 9th bit (if
enabled) and determine if any error occurred
during reception.
Read the 8-bit received data by reading the
RCREG register.
If any error occurred, clear the error by clearing
bit, CREN.
If using interrupts, ensure that the GIE and PEIE
bits in the INTCON register (INTCON<7:6>) are
set.
TABLE 17-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
49
RCSTA
RCREG
TXSTA
EUSART Receive Register
49
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
49
BAUDCON
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
49
SPBRGH
EUSART Baud Rate Generator Register High Byte
49
SPBRG
EUSART Baud Rate Generator Register Low Byte
49
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave reception.
Note 1: These bits are not implemented on 28-pin devices and should be read as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 213
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 214
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
18.0
10-BIT ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
The Analog-to-Digital (A/D) converter module has
10 inputs for the 28-pin devices and 13 for the 40/44-pin
devices. This module allows conversion of an analog
input signal to a corresponding 10-bit digital number.
The ADCON0 register, shown in Register 18-1,
controls the operation of the A/D module. The
ADCON1 register, shown in Register 18-2, configures
the functions of the port pins. The ADCON2 register,
shown in Register 18-3, configures the A/D clock
source, programmed acquisition time and justification.
The module has five registers:
•
•
•
•
•
A/D Result High Register (ADRESH)
A/D Result Low Register (ADRESL)
A/D Control Register 0 (ADCON0)
A/D Control Register 1 (ADCON1)
A/D Control Register 2 (ADCON2)
REGISTER 18-1:
ADCON0: A/D CONTROL REGISTER 0
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ADCAL
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
ADCAL: A/D Calibration bit
1 = Calibration is performed on next A/D conversion
0 = Normal A/D converter operation (no calibration is performed)
bit 6
Unimplemented: Read as ‘0’
bit 5-2
CHS<3:0>: Analog Channel Select bits
0000 = Channel 0 (AN0)
0001 = Channel 1 (AN1)
0010 = Channel 2 (AN2)
0011 = Channel 3 (AN3)
0100 = Channel 4 (AN4)
0101 = Channel 5 (AN5)(1,2)
0110 = Channel 6 (AN6)(1,2)
0111 = Channel 7 (AN7)(1,2)
1000 = Channel 8 (AN8)
1001 = Channel 9 (AN9)
1010 = Channel 10 (AN10)
1011 = Channel 11 (AN11)
1100 = Channel 12 (AN12)
1101 = Unimplemented(2)
1110 = Unimplemented(2)
1111 = Unimplemented(2)
bit 1
GO/DONE: A/D Conversion Status bit
When ADON = 1:
1 = A/D conversion in progress
0 = A/D Idle
bit 0
ADON: A/D On bit
1 = A/D converter module is enabled
0 = A/D converter module is disabled
Note 1:
2:
x = Bit is unknown
These channels are not implemented on 28-pin devices.
Performing a conversion on unimplemented channels will return a floating input measurement.
© 2009 Microchip Technology Inc.
DS39682E-page 215
PIC18F45J10 FAMILY
REGISTER 18-2:
ADCON1: A/D CONTROL REGISTER 1
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
PCFG<3:0>
AN5(1)
AN4
AN3
AN2
AN1
AN0
PCFG<3:0>: A/D Port Configuration Control bits:
AN6(1)
bit 3-0
AN7(1)
VCFG0: Voltage Reference Configuration bit (VREF+ source)
1 = VREF+ (AN3)
0 = VDD
AN8
bit 4
AN9
VCFG1: Voltage Reference Configuration bit (VREF- source)
1 = VREF- (AN2)
0 = VSS
AN10
bit 5
AN11
Unimplemented: Read as ‘0’
AN12
bit 7-6
x = Bit is unknown
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
A
A
A
D
D
D
D
D
D
D
D
D
D
D
D
D
A
A
A
A
D
D
D
D
D
D
D
D
D
D
D
D
A
A
A
A
A
D
D
D
D
D
D
D
D
D
D
D
A
A
A
A
A
A
D
D
D
D
D
D
D
D
D
D
A
A
A
A
A
A
A
D
D
D
D
D
D
D
D
D
A
A
A
A
A
A
A
A
D
D
D
D
D
D
D
D
A
A
A
A
A
A
A
A
A
D
D
D
D
D
D
D
A
A
A
A
A
A
A
A
A
A
D
D
D
D
D
D
A
A
A
A
A
A
A
A
A
A
A
D
D
D
D
D
A
A
A
A
A
A
A
A
A
A
A
A
D
D
D
D
A
A
A
A
A
A
A
A
A
A
A
A
A
D
D
D
A
A
A
A
A
A
A
A
A
A
A
A
A
A
D
D
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
D
A = Analog input
Note 1:
DS39682E-page 216
D = Digital I/O
AN5 through AN7 are available only on 40/44-pin devices.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 18-3:
ADCON2: A/D CONTROL REGISTER 2
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ADFM
—
ACQT2
ACQT1
ACQT0
ADCS2
ADCS1
ADCS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
ADFM: A/D Result Format Select bit
1 = Right justified
0 = Left justified
bit 6
Unimplemented: Read as ‘0’
bit 5-3
ACQT<2:0>: A/D Acquisition Time Select bits
111 = 20 TAD
110 = 16 TAD
101 = 12 TAD
100 = 8 TAD
011 = 6 TAD
010 = 4 TAD
001 = 2 TAD
000 = 0 TAD(1)
bit 2-0
ADCS<2:0>: A/D Conversion Clock Select bits
111 = FRC (clock derived from A/D RC oscillator)(1)
110 = FOSC/64
101 = FOSC/16
100 = FOSC/4
011 = FRC (clock derived from A/D RC oscillator)(1)
010 = FOSC/32
001 = FOSC/8
000 = FOSC/2
Note 1:
x = Bit is unknown
If the A/D FRC clock source is selected, a delay of one TCY (instruction cycle) is added before the A/D
clock starts. This allows the SLEEP instruction to be executed before starting a conversion.
© 2009 Microchip Technology Inc.
DS39682E-page 217
PIC18F45J10 FAMILY
The analog reference voltage is software selectable to
either the device’s positive and negative supply voltage
(VDD and VSS), or the voltage level on the RA3/AN3/
VREF+ and RA2/AN2/VREF-/CVREF pins.
A device Reset forces all registers to their Reset state.
This forces the A/D module to be turned off and any
conversion in progress is aborted.
Each port pin associated with the A/D converter can be
configured as an analog input, or as a digital I/O. The
ADRESH and ADRESL registers contain the result of
the A/D conversion. When the A/D conversion is complete, the result is loaded into the ADRESH:ADRESL
register pair, the GO/DONE bit (ADCON0 register) is
cleared and A/D Interrupt Flag bit, ADIF, is set. The block
diagram of the A/D module is shown in Figure 18-1.
The A/D converter has a unique feature of being able
to operate while the device is in Sleep mode. To operate in Sleep, the A/D conversion clock must be derived
from the A/D’s internal RC oscillator.
The output of the sample and hold is the input into the
converter, which generates the result via successive
approximation.
FIGURE 18-1:
A/D BLOCK DIAGRAM
CHS<3:0>
1100
1011
1010
1001
(Input Voltage)
Reference
Voltage
VREF+
VREF-
AN9
0111
AN7(1)
0110
AN6(1)
0101
AN5(1)
0100
AN4
0011
AN3
0001
VDD(2)
AN10
AN8
0010
VCFG<1:0>
AN11
1000
VAIN
10-Bit
A/D
Converter
AN12
0000
AN2
AN1
AN0
X0
X1
1X
0X
VSS(2)
Note 1:
2:
Channels AN5 through AN7 are not available in 28-pin devices.
I/O pins have diode protection to VDD and VSS.
DS39682E-page 218
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
After the A/D module has been configured as desired,
the selected channel must be acquired before the
conversion is started. The analog input channels must
have their corresponding TRIS bits selected as an
input. To determine acquisition time, see Section 18.1
“A/D Acquisition Requirements”. After this acquisition time has elapsed, the A/D conversion can be
started. An acquisition time can be programmed to
occur between setting the GO/DONE bit and the actual
start of the conversion.
2.
Configure A/D interrupt (if desired):
• Clear ADIF bit
• Set ADIE bit
• Set GIE bit
Wait the required acquisition time (if required).
Start conversion:
• Set GO/DONE bit (ADCON0<1>)
Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared
3.
4.
5.
The following steps should be followed to do an A/D
conversion:
1.
Configure the A/D module:
• Configure analog pins, voltage reference and
digital I/O (ADCON1)
• Select A/D input channel (ADCON0)
• Select A/D acquisition time (ADCON2)
• Select A/D conversion clock (ADCON2)
• Turn on A/D module (ADCON0)
FIGURE 18-2:
OR
• Waiting for the A/D interrupt
Read A/D Result registers (ADRESH:ADRESL);
clear bit, ADIF, if required.
For next conversion, go to step 1 or step 2, as
required. The A/D conversion time per bit is
defined as TAD. A minimum wait of 2 TAD is
required before next acquisition starts.
6.
7.
ANALOG INPUT MODEL
VDD
RS
VAIN
ANx
VT = 0.6V
RIC ≤ 1k
CPIN
5 pF
Sampling
Switch
VT = 0.6V
SS
RSS
ILEAKAGE
±100 nA
CHOLD = 25 pF
VSS
Legend: CPIN
= Input Capacitance
VT
= Threshold Voltage
ILEAKAGE = Leakage Current at the pin due to
various junctions
RIC
= Interconnect Resistance
SS
= Sampling Switch
CHOLD
= Sample/Hold Capacitance (from DAC)
RSS
= Sampling Switch Resistance
© 2009 Microchip Technology Inc.
VDD
1
2
3
4
Sampling Switch (kΩ)
DS39682E-page 219
PIC18F45J10 FAMILY
18.1
A/D Acquisition Requirements
For the A/D converter to meet its specified accuracy,
the charge holding capacitor (CHOLD) must be allowed
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 18-2. The
source impedance (RS) and the internal sampling
switch (RSS) impedance directly affect the time
required to charge the capacitor CHOLD. The sampling
switch (RSS) impedance varies over the device voltage
(VDD). The source impedance affects the offset voltage
at the analog input (due to pin leakage current). The
maximum recommended impedance for analog
sources is 2.5 kΩ. After the analog input channel is
selected (changed), the channel must be sampled for
at least the minimum acquisition time before starting a
conversion.
EQUATION 18-1:
CHOLD
Rs
Conversion Error
VDD
Temperature
=
=
≤
=
=
25 pF
2.5 kΩ
1/2 LSb
3V → Rss = 2 kΩ
85°C (system max.)
ACQUISITION TIME
=
Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient
=
TAMP + TC + TCOFF
EQUATION 18-2:
VHOLD
or
TC
Equation 18-3 shows the calculation of the minimum
required acquisition time, TACQ. This calculation is
based on the following application system
assumptions:
When the conversion is started, the
holding capacitor is disconnected from the
input pin.
Note:
TACQ
To calculate the minimum acquisition time,
Equation 18-1 may be used. This equation assumes
that 1/2 LSb error is used (1024 steps for the A/D). The
1/2 LSb error is the maximum error allowed for the A/D
to meet its specified resolution.
A/D MINIMUM CHARGING TIME
=
(VREF – (VREF/2048)) • (1 – e(-TC/CHOLD(RIC + RSS + RS)))
=
-(CHOLD)(RIC + RSS + RS) ln(1/2048)
EQUATION 18-3:
CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
TACQ
=
TAMP + TC + TCOFF
TAMP
=
0.2 μs
TCOFF
=
(Temp – 25°C)(0.02 μs/°C)
(85°C – 25°C)(0.02 μs/°C)
1.2 μs
Temperature coefficient is only required for temperatures > 25°C. Below 25°C, TCOFF = 0 ms.
TC
=
-(CHOLD)(RIC + RSS + RS) ln(1/2048) μs
-(25 pF) (1 kΩ + 2 kΩ + 2.5 kΩ) ln(0.0004883) μs
1.05 μs
TACQ
=
0.2 μs + 1 μs + 1.2 μs
2.4 μs
DS39682E-page 220
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
18.2
Selecting and Configuring
Automatic Acquisition Time
The ADCON2 register allows the user to select an
acquisition time that occurs each time the GO/DONE
bit is set.
When the GO/DONE bit is set, sampling is stopped and
a conversion begins. The user is responsible for ensuring the required acquisition time has passed between
selecting the desired input channel and setting the
GO/DONE bit. This occurs when the ACQT<2:0> bits
(ADCON2<5:3>) remain in their Reset state (‘000’) and
is compatible with devices that do not offer
programmable acquisition times.
If desired, the ACQT bits can be set to select a programmable acquisition time for the A/D module. When
the GO/DONE bit is set, the A/D module continues to
sample the input for the selected acquisition time, then
automatically begins a conversion. Since the acquisition time is programmed, there may be no need to wait
for an acquisition time between selecting a channel and
setting the GO/DONE bit.
In either case, when the conversion is completed, the
GO/DONE bit is cleared, the ADIF flag is set and the
A/D begins sampling the currently selected channel
again. If an acquisition time is programmed, there is
nothing to indicate if the acquisition time has ended or
if the conversion has begun.
18.3
Selecting the A/D Conversion
Clock
The A/D conversion time per bit is defined as TAD. The
A/D conversion requires 11 TAD per 10-bit conversion.
The source of the A/D conversion clock is software
selectable.
There are seven possible options for TAD:
•
•
•
•
•
•
•
2 TOSC
4 TOSC
8 TOSC
16 TOSC
32 TOSC
64 TOSC
Internal RC Oscillator
TABLE 18-1:
TAD vs. DEVICE OPERATING
FREQUENCIES
AD Clock Source (TAD)
Operation
ADCS<2:0>
Maximum
Device
Frequency
2 TOSC
000
2.86 MHz
TOSC
100
5.71 MHz
8 TOSC
001
11.43 MHz
16 TOSC
101
22.86 MHz
32 TOSC
010
40.0 MHz
64 TOSC
110
40.0 MHz
RC(2)
x11
1.00 MHz(1)
4
Note 1: The RC source has a typical TAD time of
4 μs.
2: For device frequencies above 1 MHz, the
device must be in Sleep mode for the entire
conversion or the A/D accuracy may be out
of specification.
18.4
Configuring Analog Port Pins
The ADCON1, TRISA, TRISF and TRISH registers
control the operation of the A/D port pins. The port pins
needed as analog inputs must have their corresponding TRIS bits set (input). If the TRIS bit is cleared
(output), the digital output level (VOH or VOL) will be
converted.
The A/D operation is independent of the state of the
CHS<3:0> bits and the TRIS bits.
Note 1: When reading the PORT register, all pins
configured as analog input channels will
read as cleared (a low level). Pins configured as digital inputs will convert an
analog input. Analog levels on a digitally
configured input will be accurately
converted.
2: Analog levels on any pin defined as a
digital input may cause the digital input
buffer to consume current out of the
device’s specification limits.
For correct A/D conversions, the A/D conversion clock
(TAD) must be as short as possible but greater than the
minimum TAD (see parameter 130 in Table 24-25 for
more information).
Table 18-1 shows the resultant TAD times derived from
the device operating frequencies and the A/D clock
source selected.
© 2009 Microchip Technology Inc.
DS39682E-page 221
PIC18F45J10 FAMILY
18.5
A/D Conversions
18.6
Figure 18-3 shows the operation of the A/D converter
after the GO/DONE bit has been set and the
ACQT<2:0> bits are cleared. A conversion is started
after the following instruction to allow entry into Sleep
mode before the conversion begins.
An A/D conversion can be started by the “Special Event
Trigger” of the ECCP2 module. This requires that the
CCP2M<3:0> bits (CCP2CON<3:0>) be programmed
as ‘1011’ and that the A/D module is enabled (ADON
bit is set). When the trigger occurs, the GO/DONE bit
will be set, starting the A/D acquisition and conversion
and the Timer1 (or Timer3) counter will be reset to zero.
Timer1 (or Timer3) is reset to automatically repeat the
A/D acquisition period with minimal software overhead
(moving ADRESH/ADRESL to the desired location).
The appropriate analog input channel must be selected
and the minimum acquisition period is either timed by
the user, or an appropriate TACQ time is selected before
the Special Event Trigger sets the GO/DONE bit (starts
a conversion).
Figure 18-4 shows the operation of the A/D converter
after the GO/DONE bit has been set, the ACQT<2:0>
bits are set to ‘010’ and selecting a 4 TAD acquisition
time before the conversion starts.
Clearing the GO/DONE bit during a conversion will abort
the current conversion. The A/D Result register pair will
NOT be updated with the partially completed A/D
conversion sample. This means the ADRESH:ADRESL
registers will continue to contain the value of the last
completed conversion (or the last value written to the
ADRESH:ADRESL registers).
If the A/D module is not enabled (ADON is cleared), the
Special Event Trigger will be ignored by the A/D module
but will still reset the Timer1 (or Timer3) counter.
After the A/D conversion is completed or aborted, a
2 TAD wait is required before the next acquisition can be
started. After this wait, acquisition on the selected
channel is automatically started.
Note:
Use of the ECCP2 Trigger
The GO/DONE bit should NOT be set in
the same instruction that turns on the A/D.
FIGURE 18-3:
A/D CONVERSION TAD CYCLES (ACQT<2:0> = 000, TACQ = 0)
TCY - TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11
b4
b1
b0
b6
b7
b2
b9
b8
b3
b5
Conversion starts
Holding capacitor is disconnected from analog input (typically 100 ns)
Set GO/DONE bit
Next Q4: ADRESH/ADRESL is loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
A/D CONVERSION TAD CYCLES (ACQT<2:0> = 010, TACQ = 4 TAD)
FIGURE 18-4:
TAD Cycles
TACQT Cycles
1
2
3
Automatic
Acquisition
Time
4
1
b9
3
4
5
b8
b7
b6
6
b5
7
b4
8
9
10
11
b3
b2
b1
b0
Conversion starts
(Holding capacitor is disconnected)
Set GO/DONE bit
(Holding capacitor continues
acquiring input)
DS39682E-page 222
2
Next Q4: ADRESH:ADRESL is loaded, GO/DONE bit is cleared,
ADIF bit is set, holding capacitor is reconnected to analog input.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
18.7
A/D Converter Calibration
The A/D converter in the PIC18F45J10 family of
devices includes a self-calibration feature which compensates for any offset generated within the module.
The calibration process is automated and is initiated by
setting the ADCAL bit (ADCON0<7>). The next time
the GO/DONE bit is set, the module will perform a
“dummy” conversion (that is, with reading none of the
input channels) and store the resulting value internally
to compensate for offset. Thus, subsequent offsets will
be compensated.
The calibration process assumes that the device is in a
relatively steady-state operating condition. If A/D
calibration is used, it should be performed after each
device Reset or if there are other major changes in
operating conditions.
18.8
Operation in Power-Managed
Modes
The selection of the automatic acquisition time and A/D
conversion clock is determined in part by the clock
source and frequency while in a power-managed mode.
TABLE 18-2:
Name
If the A/D is expected to operate while the device is in
a power-managed mode, the ACQT<2:0> and
ADCS<2:0> bits in ADCON2 should be updated in
accordance with the power-managed mode clock that
will be used. After the power-managed mode is entered
(either of the power-managed Run modes), an A/D
acquisition or conversion may be started. Once an
acquisition or conversion is started, the device should
continue to be clocked by the same power-managed
mode clock source until the conversion has been completed. If desired, the device may be placed into the
corresponding power-managed Idle mode during the
conversion.
If the power-managed mode clock frequency is less
than 1 MHz, the A/D RC clock source should be
selected.
Operation in the Sleep mode requires the A/D RC clock
to be selected. If bits, ACQT<2:0>, are set to ‘000’ and
a conversion is started, the conversion will be delayed
one instruction cycle to allow execution of the SLEEP
instruction and entry to Sleep mode. The IDLEN and
SCS bits in the OSCCON register must have already
been cleared prior to starting the conversion.
REGISTERS ASSOCIATED WITH A/D OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
47
INTCON
GIE/GIEH PEIE/GIEL
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
49
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
49
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
49
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
49
ADRESH
A/D Result Register High Byte
48
ADRESL
A/D Result Register Low Byte
48
ADCON0
ADCAL
—
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
48
ADCON1
—
—
VCFG1
VCFG0
PCFG3
PCFG2
PCFG1
PCFG0
48
ADCON2
ADFM
—
ACQT2
ACQT1
ACQT0
ADCS2
ADCS1
ADCS0
48
—
—
RA5
—
RA3
RA2
RA1
RA0
50
PORTA
TRISA
—
—
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
50
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
50
TRISB
PORTB Data Direction Control Register
50
LATB
PORTB Data Latch Register (Read and Write to Data Latch)
50
PORTE(1)
—
—
—
—
—
RE2
RE1
RE0
50
TRISE(1)
IBF
OBF
IBOV
PSPMODE
—
TRISE2
TRISE1
TRISE0
50
—
—
—
—
—
(1)
LATE
PORTE Data Latch Register
(Read and Write to Data Latch)
50
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for A/D conversion.
Note 1: These registers and/or bits are not implemented on 28-pin devices and should be read as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 223
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 224
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
19.0
COMPARATOR MODULE
The analog comparator module contains two
comparators that can be configured in a variety of
ways. The inputs can be selected from the analog
inputs multiplexed with pins RA0 through RA5, as well
as the on-chip voltage reference (see Section 20.0
“Comparator Voltage Reference Module”). The digital outputs (normal or inverted) are available at the pin
level and can also be read through the control register.
REGISTER 19-1:
The CMCON register (Register 19.1) selects the
comparator input and output configuration. Block
diagrams of the various comparator configurations are
shown in Figure 19-1.
CMCON: COMPARATOR CONTROL REGISTER
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-1
R/W-1
R/W-1
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
C2OUT: Comparator 2 Output bit
When C2INV = 0:
1 = C2 VIN+ > C2 VIN0 = C2 VIN+ < C2 VINWhen C2INV = 1:
1 = C2 VIN+ < C2 VIN0 = C2 VIN+ > C2 VIN-
bit 6
C1OUT: Comparator 1 Output bit
When C1INV = 0:
1 = C1 VIN+ > C1 VIN0 = C1 VIN+ < C1 VINWhen C1INV = 1:
1 = C1 VIN+ < C1 VIN0 = C1 VIN+ > C1 VIN-
bit 5
C2INV: Comparator 2 Output Inversion bit
1 = C2 output inverted
0 = C2 output not inverted
bit 4
C1INV: Comparator 1 Output Inversion bit
1 = C1 output inverted
0 = C1 output not inverted
bit 3
CIS: Comparator Input Switch bit
When CM<2:0> = 110:
1 = C1 VIN- connects to RA3/AN3/VREF+
C2 VIN- connects to RA2/AN2/VREF-/CVREF
0 = C1 VIN- connects to RA0/AN0
C2 VIN- connects to RA1/AN1
bit 2-0
CM<2:0>: Comparator Mode bits
Figure 19-1 shows the Comparator modes and the CM<2:0> bit settings.
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS39682E-page 225
PIC18F45J10 FAMILY
19.1
Comparator Configuration
There are eight modes of operation for the comparators, shown in Figure 19-1. Bits, CM<2:0> of the
CMCON register, are used to select these modes. The
TRISA register controls the data direction of the comparator pins for each mode. If the Comparator mode is
FIGURE 19-1:
Comparators Off (POR Default Value)
CM<2:0> = 111
A
VIN-
RA3/AN3/ A
VREF+
VIN+
A
VIN-
RA1/AN1
RA2/AN2/ A
VREF-/CVREF
VIN+
C1
Off (Read as ‘0’)
C2
Off (Read as ‘0’)
Two Independent Comparators
CM<2:0> = 010
A
VIN-
RA3/AN3/ A
VREF+
VIN+
A
VIN-
RA2/AN2/ A
VREF-/CVREF
VIN+
RA0/AN0
RA1/AN1
Comparator interrupts should be disabled
during a Comparator mode change;
otherwise, a false interrupt may occur.
Note:
COMPARATOR I/O OPERATING MODES
Comparators Reset
CM<2:0> = 000
RA0/AN0
changed, the comparator output level may not be valid
for the specified mode change delay shown in
Section 24.0 “Electrical Characteristics”.
RA0/AN0
D
VIN-
RA3/AN3/
VREF+
D
VIN+
RA1/AN1
D
VIN-
D
RA2/AN2/
VREF-/CVREF
VIN+
C1
Off (Read as ‘0’)
C2
Off (Read as ‘0’)
Two Independent Comparators with Outputs
CM<2:0> = 011
RA0/AN0
A
C1
C1OUT
RA3/AN3/ A
VREF+
RB5/KBI1/
T0CKI/C1OUT*
C2
C2OUT
RA1/AN1
VINVIN+
A
VIN-
RA2/AN2/ A
VREF-/CVREF
VIN+
C1
C1OUT
C2
C2OUT
RA5/AN4/SS1/C2OUT*
Two Common Reference Comparators
CM<2:0> = 100
A
VIN-
RA3/AN3/ A
VREF+
VIN+
A
VIN-
RA2/AN2/ D
VREF-/CVREF
VIN+
RA0/AN0
RA1/AN1
Two Common Reference Comparators with Outputs
CM<2:0> = 101
A
VIN-
C1
C1OUT
A
RA3/AN3/
VREF+
RB5/KBI1/
T0CKI/C1OUT*
VIN+
C2
C2OUT
RA1/AN1
A
VIN-
D
RA2/AN2/
VREF-/CVREF
VIN+
RA0/AN0
C1
C1OUT
C2
C2OUT
RA5/AN4/SS1/C2OUT*
One Independent Comparator with Output
CM<2:0> = 001
A
VIN-
RA3/AN3/ A
VREF+
VIN+
RA0/AN0
C1
C1OUT
RB5/KBI1/T0CKI/C1OUT*
RA1/AN1
D
RA2/AN2/ D
VREF-/CVREF/
RA0/AN0
A
RA3/AN3/
VREF+
A
RA1/AN1
VINVIN+
Four Inputs Multiplexed to Two Comparators
CM<2:0> = 110
C2
Off (Read as ‘0’)
CIS = 0
CIS = 1
VIN-
CIS = 0
CIS = 1
VIN-
VIN+
C1
C1OUT
C2
C2OUT
A
A
RA2/AN2/
VREF-/CVREF/
VIN+
CVREF
From VREF Module
A = Analog Input, port reads zeros always
D = Digital Input
CIS (CMCON<3>) is the Comparator Input Switch
* Setting the TRISA<5> bit will disable the comparator outputs by configuring the pins as inputs.
DS39682E-page 226
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
19.2
19.3.2
Comparator Operation
A single comparator is shown in Figure 19-2, along with
the relationship between the analog input levels and
the digital output. When the analog input at VIN+ is less
than the analog input, VIN-, the output of the
comparator is a digital low level. When the analog input
at VIN+ is greater than the analog input, VIN-, the output
of the comparator is a digital high level. The shaded
areas of the output of the comparator in Figure 19-2
represent the uncertainty due to input offsets and
response time.
19.3
Depending on the comparator operating mode, either
an external or internal voltage reference may be used.
The analog signal present at VIN- is compared to the
signal at VIN+ and the digital output of the comparator
is adjusted accordingly (Figure 19-2).
FIGURE 19-2:
The comparator module also allows the selection of an
internally generated voltage reference from the
comparator voltage reference module. This module is
described in more detail in Section 20.0 “Comparator
Voltage Reference Module”.
The internal reference is only available in the mode
where four inputs are multiplexed to two comparators
(CM<2:0> = 110). In this mode, the internal voltage
reference is applied to the VIN+ pin of both comparators.
19.4
Comparator Reference
SINGLE COMPARATOR
VIN-
+
–
Output
VINVIN+
Comparator Outputs
The comparator outputs are read through the CMCON
register. These bits are read-only. The comparator
outputs may also be directly output to the RB5 and RA5
I/O pins. When enabled, multiplexors in the output path
of the RB5 and RA5 pins will switch and the output of
each pin will be the unsynchronized output of the
comparator. The uncertainty of each of the
comparators is related to the input offset voltage and
the response time given in the specifications.
Figure 19-3 shows the comparator output block
diagram.
The TRISA bits will still function as an output enable/
disable for the RB5 and RA5 pins while in this mode.
Output
19.3.1
Comparator Response Time
Response time is the minimum time, after selecting a
new reference voltage or input source, before the
comparator output has a valid level. If the internal reference is changed, the maximum delay of the internal
voltage reference must be considered when using the
comparator outputs. Otherwise, the maximum delay of
the comparators should be used (see Section 24.0
“Electrical Characteristics”).
19.5
VIN+
INTERNAL REFERENCE SIGNAL
The polarity of the comparator outputs can be changed
using the C2INV and C1INV bits (CMCON<5:4>).
EXTERNAL REFERENCE SIGNAL
When external voltage references are used, the
comparator module can be configured to have the comparators operate from the same or different reference
sources. However, threshold detector applications may
require the same reference. The reference signal must
be between VSS and VDD and can be applied to either
pin of the comparator(s).
© 2009 Microchip Technology Inc.
Note 1: When reading the PORT register, all pins
configured as analog inputs will read as a
‘0’. Pins configured as digital inputs will
convert an analog input according to the
Schmitt Trigger input specification.
2: Analog levels on any pin defined as a
digital input may cause the input buffer to
consume more current than is specified.
DS39682E-page 227
PIC18F45J10 FAMILY
+
To RB5 or
RA5 pin
-
Port Pins
COMPARATOR OUTPUT BLOCK DIAGRAM
MULTIPLEX
FIGURE 19-3:
D
Q
Bus
Data
CxINV
Read CMCON
EN
D
Q
EN
CL
From
Other
Comparator
Reset
19.6
Comparator Interrupts
The comparator interrupt flag is set whenever there is
a change in the output value of either comparator.
Software will need to maintain information about the
status of the output bits, as read from CMCON<7:6>, to
determine the actual change that occurred. The CMIF
bit (PIR2<6>) is the Comparator Interrupt Flag. The
CMIF bit must be reset by clearing it. Since it is also
possible to write a ‘1’ to this register, a simulated
interrupt may be initiated.
Both the CMIE bit (PIE2<6>) and the PEIE bit
(INTCON<6>) must be set to enable the interrupt. In
addition, the GIE bit (INTCON<7>) must also be set. If
any of these bits are clear, the interrupt is not enabled,
though the CMIF bit will still be set if an interrupt
condition occurs.
Note:
If a change in the CMCON register
(C1OUT or C2OUT) should occur when a
read operation is being executed (start of
the Q2 cycle), then the CMIF (PIR2
register) interrupt flag may not get set.
The user, in the Interrupt Service Routine, can clear the
interrupt in the following manner:
a)
b)
Set
CMIF
bit
19.7
Comparator Operation
During Sleep
When a comparator is active and the device is placed
in Sleep mode, the comparator remains active and the
interrupt is functional, if enabled. This interrupt will
wake-up the device from Sleep mode, when enabled.
Each operational comparator will consume additional
current, as shown in the comparator specifications. To
minimize power consumption while in Sleep mode, turn
off the comparators (CM<2:0> = 111) before entering
Sleep. If the device wakes up from Sleep, the contents
of the CMCON register are not affected.
19.8
Effects of a Reset
A device Reset forces the CMCON register to its Reset
state, causing the comparator modules to be turned off
(CM<2:0> = 111). However, the input pins (RA0
through RA3) are configured as analog inputs by
default on device Reset. The I/O configuration for these
pins is determined by the setting of the PCFG<3:0> bits
(ADCON1<3:0>). Therefore, device current is
minimized when analog inputs are present at Reset
time.
Any read or write of CMCON will end the
mismatch condition.
Clear flag bit CMIF.
A mismatch condition will continue to set flag bit, CMIF.
Reading CMCON will end the mismatch condition and
allow flag bit, CMIF, to be cleared.
DS39682E-page 228
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
19.9
range by more than 0.6V in either direction, one of the
diodes is forward biased and a latch-up condition may
occur. A maximum source impedance of 10 kΩ is
recommended for the analog sources. Any external
component connected to an analog input pin, such as
a capacitor or a Zener diode, should have very little
leakage current.
Analog Input Connection
Considerations
A simplified circuit for an analog input is shown in
Figure 19-4. Since the analog pins are connected to a
digital output, they have reverse biased diodes to VDD
and VSS. The analog input, therefore, must be between
VSS and VDD. If the input voltage deviates from this
FIGURE 19-4:
COMPARATOR ANALOG INPUT MODEL
VDD
VT = 0.6V
RS < 10k
RIC
Comparator
Input
AIN
CPIN
5 pF
VA
VT = 0.6V
ILEAKAGE
±100 nA
VSS
CPIN
VT
ILEAKAGE
RIC
RS
VA
Legend:
TABLE 19-1:
Name
CMCON
CVRCON
INTCON
=
=
=
=
=
=
Input Capacitance
Threshold Voltage
Leakage Current at the pin due to various junctions
Interconnect Resistance
Source Impedance
Analog Voltage
REGISTERS ASSOCIATED WITH COMPARATOR MODULE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
49
CVREN
CVROE
GIE/GIEH PEIE/GIEL
CVRR
CVRSS
CVR3
CVR2
CVR1
CVR0
49
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
50
PIR2
OSCFIF
CMIF
—
—
BCL1IF
—
—
CCP2IF
49
PIE2
OSCFIE
CMIE
—
—
BCL1IE
—
—
CCP2IE
49
IPR2
OSCFIP
CMIP
—
—
BCL1IP
—
—
CCP2IP
49
PORTA
—
—
RA5
—
RA3
RA2
RA1
RA0
50
LATA
—
—
TRISA
—
—
PORTA Data Latch Register (Read and Write to Data Latch)
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
50
50
Legend: — = unimplemented, read as ‘0’. Shaded cells are unused by the comparator module.
© 2009 Microchip Technology Inc.
DS39682E-page 229
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 230
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
20.0
COMPARATOR VOLTAGE
REFERENCE MODULE
The comparator voltage reference is a 16-tap resistor
ladder network that provides a selectable reference
voltage. Although its primary purpose is to provide a
reference for the analog comparators, it may also be
used independently of them.
A block diagram of the module is shown in Figure 20-1.
The resistor ladder is segmented to provide two ranges
of CVREF values and has a power-down function to
conserve power when the reference is not being used.
The module’s supply reference can be provided from
either device VDD/VSS or an external voltage reference.
20.1
Configuring the Comparator
Voltage Reference
The voltage reference module is controlled through the
CVRCON register (Register 20-1). The comparator
voltage reference provides two ranges of output
voltage, each with 16 distinct levels. The range to be
REGISTER 20-1:
R/W-0
CVREN
used is selected by the CVRR bit (CVRCON<5>). The
primary difference between the ranges is the size of the
steps selected by the CVREF Selection bits
(CVR<3:0>), with one range offering finer resolution.
The equations used to calculate the output of the
comparator voltage reference are as follows:
If CVRR = 1:
CVREF = ((CVR<3:0>)/24) x CVRSRC
If CVRR = 0:
CVREF = (CVRSRC x 1/4) + (((CVR<3:0>)/32) x
CVRSRC)
The comparator reference supply voltage can come
from either VDD and VSS, or the external VREF+ and
VREF- that are multiplexed with RA2 and RA3. The
voltage source is selected by the CVRSS bit
(CVRCON<4>).
The settling time of the comparator voltage reference
must be considered when changing the CVREF
output (see Table 24-3 in Section 24.0 “Electrical
Characteristics”).
CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER
R/W-0
CVROE
(1)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
CVRR
CVRSS
CVR3
CVR2
CVR1
CVR0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
CVREN: Comparator Voltage Reference Enable bit
1 = CVREF circuit powered on
0 = CVREF circuit powered down
bit 6
CVROE: Comparator VREF Output Enable bit(1)
1 = CVREF voltage level is also output on the RA2/AN2/VREF-/CVREF pin
0 = CVREF voltage is disconnected from the RA2/AN2/VREF-/CVREF pin
bit 5
CVRR: Comparator VREF Range Selection bit
1 = 0 to 0.667 CVRSRC, with CVRSRC/24 step size (low range)
0 = 0.25 CVRSRC to 0.75 CVRSRC, with CVRSRC/32 step size (high range)
bit 4
CVRSS: Comparator VREF Source Selection bit
1 = Comparator reference source, CVRSRC = (VREF+) – (VREF-)
0 = Comparator reference source, CVRSRC = VDD – VSS
bit 3-0
CVR<3:0>: Comparator VREF Value Selection bits (0 ≤ (CVR<3:0>) ≤ 15)
When CVRR = 1:
CVREF = ((CVR<3:0>)/24) • (CVRSRC)
When CVRR = 0:
CVREF = (CVRSRC/4) + ((CVR<3:0>)/32) • (CVRSRC)
Note 1:
CVROE overrides the TRISA<2> bit setting.
© 2009 Microchip Technology Inc.
DS39682E-page 231
PIC18F45J10 FAMILY
FIGURE 20-1:
COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
VREF+
VDD
CVRSS = 1
8R
CVRSS = 0
CVR<3:0>
R
CVREN
R
R
16-to-1 MUX
R
16 Steps
R
CVREF
R
R
CVRR
VREF-
8R
CVRSS = 1
CVRSS = 0
20.2
Voltage Reference Accuracy/Error
The full range of voltage reference cannot be realized
due to the construction of the module. The transistors
on the top and bottom of the resistor ladder network
(Figure 20-1) keep CVREF from approaching the reference source rails. The voltage reference is derived
from the reference source; therefore, the CVREF output
changes with fluctuations in that source. The tested
absolute accuracy of the voltage reference can be
found in Section 24.0 “Electrical Characteristics”.
20.3
Operation During Sleep
When the device wakes up from Sleep through an
interrupt or a Watchdog Timer time-out, the contents of
the CVRCON register are not affected. To minimize
current consumption in Sleep mode, the voltage
reference should be disabled.
20.4
Effects of a Reset
A device Reset disables the voltage reference by
clearing bit, CVREN (CVRCON<7>). This Reset also
disconnects the reference from the RA2 pin by clearing
bit, CVROE (CVRCON<6>) and selects the high-voltage
range by clearing bit, CVRR (CVRCON<5>). The CVR
value select bits are also cleared.
20.5
Connection Considerations
The voltage reference module operates independently
of the comparator module. The output of the reference
generator may be connected to the RA2 pin if the
CVROE bit is set. Enabling the voltage reference output onto RA2 when it is configured as a digital input will
increase current consumption. Connecting RA2 as a
digital output with CVRSS enabled will also increase
current consumption.
The RA2 pin can be used as a simple D/A output with
limited drive capability. Due to the limited current drive
capability, a buffer must be used on the voltage
reference output for external connections to VREF.
Figure 20-2 shows an example buffering technique.
DS39682E-page 232
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 20-2:
COMPARATOR VOLTAGE REFERENCE OUTPUT BUFFER EXAMPLE
PIC18F45J10
CVREF
Module
R(1)
Voltage
Reference
Output
Impedance
Note 1:
TABLE 20-1:
+
–
RA2
CVREF Output
R is dependent upon the voltage reference configuration bits, CVRCON<3:0> and CVRCON<5>.
REGISTERS ASSOCIATED WITH COMPARATOR VOLTAGE REFERENCE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
CVRCON
CVREN
CVROE
CVRR
CVRSS
CVR3
CVR2
CVR1
CVR0
49
CMCON
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
49
—
—
TRISA5
—
TRISA3
TRISA2
TRISA1
TRISA0
50
Name
TRISA
Legend: Shaded cells are not used with the comparator voltage reference.
© 2009 Microchip Technology Inc.
DS39682E-page 233
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 234
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
21.0
SPECIAL FEATURES OF THE
CPU
PIC18F45J10 family devices include several features
intended to maximize reliability and minimize cost
through elimination of external components. These are:
• Oscillator Selection
• Resets:
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• Fail-Safe Clock Monitor
• Two-Speed Start-up
• Code Protection
• In-Circuit Serial Programming™ (ICSP™)
The oscillator can be configured for the application
depending on frequency, power, accuracy and cost. All
of the options are discussed in detail in Section 3.0
“Oscillator Configurations”.
A complete discussion of device Resets and interrupts
is available in previous sections of this data sheet.
In addition to their Power-up and Oscillator Start-up
Timers provided for Resets, the PIC18F45J10 family of
devices have a configurable Watchdog Timer which is
controlled in software.
The inclusion of an internal RC oscillator also provides
the additional benefits of a Fail-Safe Clock Monitor
(FSCM) and Two-Speed Start-up. FSCM provides for
background monitoring of the peripheral clock and
automatic switchover in the event of its failure.
Two-Speed Start-up enables code to be executed
almost immediately on start-up, while the primary clock
source completes its start-up delays.
All of these features are enabled and configured by
setting the appropriate Configuration register bits.
21.1
21.1.1
CONSIDERATIONS FOR
CONFIGURING THE PIC18F45J10
FAMILY DEVICES
Unlike most PIC18 microcontrollers, devices of the
PIC18F45J10 family do not use persistent memory
registers to store configuration information. The configuration bytes are implemented as volatile memory
which means that configuration data must be
programmed each time the device is powered up.
Configuration data is stored in the four words at the top
of the on-chip program memory space, known as the
Flash Configuration Words. It is stored in program
memory in the same order shown in Table 21-1, with
CONFIG1L at the lowest address and CONFIG3H at
the highest. The data is automatically loaded in the
proper Configuration registers during device power-up.
When creating applications for these devices, users
should always specifically allocate the location of the
Flash Configuration Word for configuration data; this is
to make certain that program code is not stored in this
address when the code is compiled.
The volatile memory cells used for the Configuration
bits always reset to ‘1’ on Power-on Resets. For all
other type of Reset events, the previously programmed
values are maintained and used without reloading from
program memory.
The four Most Significant bits of CONFIG1H,
CONFIG2H and CONFIG3H in program memory
should also be ‘1111’. This makes these Configuration
Words appear to be NOP instructions in the remote
event that their locations are ever executed by
accident. Since Configuration bits are not implemented
in the corresponding locations, writing ‘1’s to these
locations has no effect on device operation.
To prevent inadvertent configuration changes during
code execution, all programmable Configuration bits
are write-once. After a bit is initially programmed during
a power cycle, it cannot be written to again. Changing
a device configuration requires a device Reset.
Configuration Bits
The Configuration bits can be programmed (read as
‘0’) or left unprogrammed (read as ‘1’) to select various
device configurations. These bits are mapped starting
at program memory location 300000h. A complete list
is shown in Table 21-1. A detailed explanation of the
various bit functions is provided in Register 21-1
through Register 21-8.
© 2009 Microchip Technology Inc.
DS39682E-page 235
PIC18F45J10 FAMILY
TABLE 21-1:
CONFIGURATION BITS AND DEVICE IDs
File Name
300000h
CONFIG1L
Default/
Unprogrammed
Value(1)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
DEBUG
XINST
STVREN
—
—
—
—
WDTEN
111- ---1
(2)
(2)
(2)
(2)
(3)
300001h
CONFIG1H
—
CP0
—
—
1111 01--
300002h
CONFIG2L
IESO
FCMEN
—
—
—
FOSC2
FOSC1
FOSC0
11-- -111
300003h
CONFIG2H
—(2)
—(2)
—(2)
—(2)
WDTPS3
WDTPS2
WDTPS1
WDTPS0
1111 1111
300004h
CONFIG3L
—
—
—
—
—
—
—
—
---- ----
300005h
CONFIG3H
—(2)
—(2)
—(2)
—(2)
—
—
—
CCP2MX
1111 ---1
3FFFFEh DEVID1
DEV2
DEV1
DEV0
REV4
REV3
REV2
REV1
REV0
xxxx xxxx(4)
3FFFFFh DEVID2
DEV10
DEV9
DEV8
DEV7
DEV6
DEV5
DEV4
DEV3
0001 110x(4)
Legend:
Note 1:
2:
3:
4:
—
—
—
—
x = unknown, u = unchanged, - = unimplemented. Shaded cells are unimplemented, read as ‘0’.
Values reflect the unprogrammed state as received from the factory and following Power-on Resets. In all other Reset
states, the configuration bytes maintain their previously programmed states.
The value of these bits in program memory should always be ‘1’. This ensures that the location is executed as a NOP if it
is accidentally executed.
This bit should always be maintained as ‘0’.
See Register 21-7 and Register 21-8 for DEVID values. These registers are read-only and cannot be programmed by
the user.
DS39682E-page 236
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 21-1:
CONFIG1L: CONFIGURATION REGISTER 1 LOW (BYTE ADDRESS 300000h)
R/WO-1
R/WO-1
R/WO-1
U-0
U-0
U-0
U-0
R/WO-1
DEBUG
XINST
STVREN
—
—
—
—
WDTEN
bit 7
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
DEBUG: Background Debugger Enable bit
1 = Background debugger disabled; RB6 and RB7 configured as general purpose I/O pins
0 = Background debugger enabled; RB6 and RB7 are dedicated to In-Circuit Debug
bit 6
XINST: Extended Instruction Set Enable bit
1 = Instruction set extension and Indexed Addressing mode enabled
0 = Instruction set extension and Indexed Addressing mode disabled (Legacy mode)
bit 5
STVREN: Stack Overflow/Underflow Reset Enable bit
1 = Reset on stack overflow/underflow enabled
0 = Reset on stack overflow/underflow disabled
bit 4-1
Unimplemented: Read as ‘0’
bit 0
WDTEN: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled (control is placed on SWDTEN bit)
REGISTER 21-2:
CONFIG1H: CONFIGURATION REGISTER 1 HIGH (BYTE ADDRESS 300001h)
U-0
U-0
U-0
U-0
U-0
R/WO-1
U-0
U-0
—(1)
—(1)
—(1)
—(1)
—(2)
CP0
—
—
bit 7
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
bit 7-4
Unimplemented: Read as ‘1’(1)
bit 3
Unimplemented: Read as ‘0’(2)
bit 2
CP0: Code Protection bit
1 = Program memory is not code-protected
0 = Program memory is code-protected
bit 1-0
Unimplemented: Read as ‘0’
Note 1:
2:
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
The value of these bits in program memory should always be ‘1’. This ensures that the location is
executed as a NOP if it is accidentally executed.
This bit should always be maintained as ‘0’.
© 2009 Microchip Technology Inc.
DS39682E-page 237
PIC18F45J10 FAMILY
REGISTER 21-3:
R/WO-1
IESO
bit 7
CONFIG2L: CONFIGURATION REGISTER 2 LOW (BYTE ADDRESS 300002h)
R/WO-1
U-0
U-0
U-0
R/WO-1
R/WO-1
R/WO-1
FCMEN
—
—
—
FOSC2
FOSC1
FOSC0
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
IESO: Two-Speed Start-up (Internal/External Oscillator Switchover) Control bit
1 = Two-Speed Start-up enabled
0 = Two-Speed Start-up disabled
bit 6
FCMEN: Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor enabled
0 = Fail-Safe Clock Monitor disabled
Unimplemented: Read as ‘0’
bit 5-3
bit 2
bit 1-0
FOSC2: Default/Reset System Clock Select bit
1 = Clock selected by FOSC<1:0> as system clock is enabled when OSCCON<1:0> = 00
0 = INTRC enabled as system clock when OSCCON<1:0> = 00
FOSC<1:0>: Oscillator Selection bits
11 = EC oscillator, PLL enabled and under software control, CLKO function on OSC2
10 = EC oscillator, CLKO function on OSC2
01 = HS oscillator, PLL enabled and under software control
00 = HS oscillator
DS39682E-page 238
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 21-4:
U-0
—(1)
CONFIG2H: CONFIGURATION REGISTER 2 HIGH (BYTE ADDRESS 300003h)
U-0
—(1)
U-0
—(1)
U-0
—(1)
R/WO-1
WDTPS3
R/WO-1
WDTPS2
R/WO-1
WDTPS1
R/WO-1
WDTPS0
bit 7
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-4
Unimplemented: Read as ‘1’(1)
bit 3-0
WDTPS<3:0>: Watchdog Timer Postscale Select bits
1111 = 1:32,768
1110 = 1:16,384
1101 = 1:8,192
1100 = 1:4,096
1011 = 1:2,048
1010 = 1:1,024
1001 = 1:512
1000 = 1:256
0111 = 1:128
0110 = 1:64
0101 = 1:32
0100 = 1:16
0011 = 1:8
0010 = 1:4
0001 = 1:2
0000 = 1:1
Note 1:
The value of these bits in program memory should always be ‘1’. This ensures that the location is
executed as a NOP if it is accidentally executed.
© 2009 Microchip Technology Inc.
DS39682E-page 239
PIC18F45J10 FAMILY
REGISTER 21-5:
CONFIG3L: CONFIGURATION REGISTER 3 LOW (BYTE ADDRESS 300004h)
U-0
U-0
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
bit 7-0
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
Unimplemented: Read as ‘0’
REGISTER 21-6:
CONFIG3H: CONFIGURATION REGISTER 3 HIGH (BYTE ADDRESS 300005h)
U-0
U-0
U-0
U-0
U-0
U-0
U-0
R/WO-1
—(1)
—(1)
—(1)
—(1)
—
—
—
CCP2MX
bit 7
bit 0
Legend:
R = Readable bit
WO = Write Once bit
-n = Value when device is unprogrammed
bit 7-1
Unimplemented: Read as ‘1’(1)
bit 0
CCP2MX: CCP2 MUX bit
1 = CCP2 is multiplexed with RC1
0 = CCP2 is multiplexed with RB3
Note 1:
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
The value of these bits in program memory should always be ‘1’. This ensures that the location is
executed as a NOP if it is accidentally executed.
DS39682E-page 240
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
REGISTER 21-7:
R
DEVID1: DEVICE ID REGISTER 1 FOR PIC18F45J10 FAMILY DEVICES
R
DEV2(1)
R
(1)
DEV1
DEV0
(1)
R
R
R
R
R
REV4
REV3
REV2
REV1
REV0
bit 7
bit 0
Legend:
R = Read-only bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
u = Unchanged from programmed state
bit 7-5
DEV<2:0>: Device ID bits
011 = PIC18LF4XJ10
010 = PIC18LF2XJ10
001 = PIC18F4XJ10
000 = PIC18F2XJ10
bit 4-0
REV<4:0>: Revision ID bits
These bits are used to indicate the device revision.
Note 1:
Where values for DEV<2:0> are shared by more than one device number, the specific device is always
identified by using the entire DEV<10:0> bit sequence.
REGISTER 21-8:
DEVID2: DEVICE ID REGISTER 2 FOR PIC18F45J10 FAMILY DEVICES
R
R
R
R
R
R
R
R
DEV10(1)
DEV9(1)
DEV8(1)
DEV7(1)
DEV6(1)
DEV5(1)
DEV4(1)
DEV3(1)
bit 7
bit 0
Legend:
R = Read-only bit
bit 7-0
Note 1:
DEV<10:3>: Device ID bits(1)
These bits are used with the DEV<2:0> bits in the Device ID Register 1 to identify the part number.
0001 1100 = PIC18FX5J10 devices
0001 1101 = PIC18FX4J10 devices
The values for DEV<10:3> may be shared with other device families. The specific device is always
identified by using the entire DEV<10:0> bit sequence.
© 2009 Microchip Technology Inc.
DS39682E-page 241
PIC18F45J10 FAMILY
21.2
Watchdog Timer (WDT)
Note 1: The CLRWDT and SLEEP instructions
clear the WDT and postscaler counts
when executed.
For PIC18F45J10 family devices, the WDT is driven by
the INTRC oscillator. When the WDT is enabled, the
clock source is also enabled. The nominal WDT period
is 4 ms and has the same stability as the INTRC
oscillator.
The 4 ms period of the WDT is multiplied by a 16-bit
postscaler. Any output of the WDT postscaler is selected
by a multiplexor, controlled by the WDTPS bits in Configuration Register 2H. Available periods range from about
4 ms to 135 seconds (2.25 minutes) depending on voltage, temperature and Watchdog postscaler. The WDT
and postscaler are cleared whenever a SLEEP or
CLRWDT instruction is executed, or a clock failure
(primary or Timer1 oscillator) has occurred.
FIGURE 21-1:
2: When a CLRWDT instruction is executed,
the postscaler count will be cleared.
21.2.1
CONTROL REGISTER
The WDTCON register (Register 21-9) is a readable
and writable register. The SWDTEN bit enables or
disables WDT operation.
WDT BLOCK DIAGRAM
Enable WDT
SWDTEN
INTRC Control
WDT Counter
Wake-up from
Power-Managed
Modes
÷128
INTRC Oscillator
Programmable Postscaler
1:1 to 1:32,768
CLRWDT
All Device Resets
WDT
Reset
Reset
WDT
4
WDTPS<3:0>
Sleep
REGISTER 21-9:
WDTCON: WATCHDOG TIMER CONTROL REGISTER
u-0
U-0
U-0
U-0
U-0
U-0
U-0
R/W-0
—
—
—
—
—
—
—
SWDTEN(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-1
Unimplemented: Read as ‘0’
bit 0
SWDTEN: Software Controlled Watchdog Timer Enable bit(1)
1 = Watchdog Timer is on
0 = Watchdog Timer is off
Note 1:
This bit has no effect if the Configuration bit, WDTEN, is enabled.
TABLE 21-2:
Name
RCON
WDTCON
x = Bit is unknown
SUMMARY OF WATCHDOG TIMER REGISTERS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset Values
on page
IPEN
—
CM
RI
TO
PD
POR
BOR
48
—
—
—
—
—
—
—
SWDTEN
48
Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Watchdog Timer.
DS39682E-page 242
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
21.3
Note:
On-Chip Voltage Regulator
The on-chip voltage regulator is only
available in parts designated with an “F”,
such as PIC18F45J10.
In parts designated “LF”, the microcontroller core is
powered from an external source that is separate from
VDD. This voltage is supplied on the VDDCORE pin.
In “F” devices, a low-ESR capacitor must be connected
to the VDDCORE/VCAP pin for proper device operation.
In parts designated with an “LF” part number (i.e.,
PIC18LF45J10), power to the core must be supplied on
VDDCORE/VCAP. It is always good design practice to
have sufficient capacitance on all supply pins.
Examples are shown in Figure 21-2.
Note:
In parts designated with an “LF”, such as
PIC18LF45J10, VDDCORE must never
exceed VDD.
21.3.1
ON-CHIP REGULATOR AND BOR
When the on-chip regulator is enabled, PIC18F45J10
family devices also have a simple brown-out capability.
If the voltage supplied to the regulator is inadequate to
maintain a regulated level, the regulator Reset circuitry
will generate a BOR Reset. This event is captured by
the BOR flag bit (RCON<0>).
The operation of the BOR is described in more detail in
Section 5.4
“Brown-out
Reset
(BOR)
(PIC18F2XJ10/4XJ10
Devices
Only)”
and
Section 5.4.1 “Detecting BOR”. The brown-out voltage
levels are specific in Section 23.1 “DC Characteristics:
Supply Voltage”.
21.3.2
POWER-UP REQUIREMENTS
The on-chip regulator is designed to meet the power-up
requirements for the device. While powering up,
VDDCORE must never exceed VDD by 0.3 volts.
The specifications for core voltage and capacitance
are listed inTable 24-4 of Section 24.0 “Electrical
Characteristics”.
FIGURE 21-2:
CONNECTIONS FOR THE
ON-CHIP REGULATOR
PIC18FXXJ10 Devices (Regulator Enabled):
3.3V
PIC18FXXJ10
VDD
VDDCORE/VCAP
CEFC
VSS
PIC18LFXXJ10 Devices (Regulator Disabled):
2.5V
PIC18LFXXJ10
VDD
VDDCORE/VCAP
VSS
OR
2.5V
3.3V
PIC18LFXXJ10
VDD
VDDCORE/VCAP
VSS
© 2009 Microchip Technology Inc.
DS39682E-page 243
PIC18F45J10 FAMILY
21.4
In all other power-managed modes, Two-Speed
Start-up is not used. The device will be clocked by the
currently selected clock source until the primary clock
source becomes available. The setting of the IESO bit
is ignored.
Two-Speed Start-up
The Two-Speed Start-up feature helps to minimize the
latency period, from oscillator start-up to code execution, by allowing the microcontroller to use the INTRC
oscillator as a clock source until the primary clock
source is available. It is enabled by setting the IESO
Configuration bit.
21.4.1
Two-Speed Start-up should be enabled only if the
primary oscillator mode is HS (Crystal-Based) modes.
Since the EC mode does not require an OST start-up
delay, Two-Speed Start-up should be disabled.
While using the INTRC oscillator in Two-Speed
Start-up, the device still obeys the normal command
sequences for entering power-managed modes,
including serial SLEEP instructions (refer to
Section 4.1.4 “Multiple Sleep Commands”). In
practice, this means that user code can change the
SCS<1:0> bit settings or issue SLEEP instructions
before the OST times out. This would allow an application to briefly wake-up, perform routine “housekeeping”
tasks and return to Sleep before the device starts to
operate from the primary oscillator.
When enabled, Resets and wake-ups from Sleep mode
cause the device to configure itself to run from the
internal oscillator block as the clock source, following
the time-out of the Power-up Timer after a POR Reset
is enabled. This allows almost immediate code execution while the primary oscillator starts and the OST is
running. Once the OST times out, the device
automatically switches to PRI_RUN mode.
FIGURE 21-3:
SPECIAL CONSIDERATIONS FOR
USING TWO-SPEED START-UP
User code can also check if the primary clock source is
currently providing the device clocking by checking the
status of the OSTS bit (OSCCON<3>). If the bit is set,
the primary oscillator is providing the clock. Otherwise,
the internal oscillator block is providing the clock during
wake-up from Reset or Sleep mode.
TIMING TRANSITION FOR TWO-SPEED START-UP (INTRC)
Q1
Q2
Q3
Q4
Q2 Q3 Q4 Q1 Q2 Q3
Q1
INTOSC
OSC1
TOST(1)
CPU Clock
Peripheral
Clock
Program
Counter
PC
Wake From Interrupt Event
Note 1:
DS39682E-page 244
PC + 2
PC + 4
PC + 6
OSTS bit Set
TOST = 1024 TOSC. These intervals are not shown to scale.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
21.5
Fail-Safe Clock Monitor
The Fail-Safe Clock Monitor (FSCM) allows the
microcontroller to continue operation in the event of an
external oscillator failure by automatically switching the
device clock to the internal oscillator block. The FSCM
function is enabled by setting the FCMEN
Configuration bit.
When FSCM is enabled, the INTRC oscillator runs at
all times to monitor clocks to peripherals and provide a
backup clock in the event of a clock failure. Clock
monitoring (shown in Figure 21-4) is accomplished by
creating a sample clock signal which is the INTRC output divided by 64. This allows ample time between
FSCM sample clocks for a peripheral clock edge to
occur. The peripheral device clock and the sample
clock are presented as inputs to the Clock Monitor latch
(CM). The CM is set on the falling edge of the device
clock source but cleared on the rising edge of the
sample clock.
FIGURE 21-4:
FSCM BLOCK DIAGRAM
Clock Monitor
Latch (CM)
(edge-triggered)
Peripheral
Clock
INTRC
Source
÷ 64
(32 μs)
488 Hz
(2.048 ms)
S
Q
C
Q
To use a higher clock speed on wake-up, the INTOSC
or postscaler clock sources can be selected to provide
a higher clock speed by setting bits IRCF<2:0>
immediately after Reset. For wake-ups from Sleep, the
INTOSC or postscaler clock sources can be selected
by setting IRCF<2:0> prior to entering Sleep mode.
The FSCM will detect failures of the primary or secondary clock sources only. If the internal oscillator block
fails, no failure would be detected, nor would any action
be possible.
21.5.1
Both the FSCM and the WDT are clocked by the
INTRC oscillator. Since the WDT operates with a
separate divider and counter, disabling the WDT has
no effect on the operation of the INTRC oscillator when
the FSCM is enabled.
As already noted, the clock source is switched to the
INTRC clock when a clock failure is detected; this may
mean a substantial change in the speed of code execution. If the WDT is enabled with a small prescale value,
a decrease in clock speed allows a WDT time-out to
occur and a subsequent device Reset. For this reason,
Fail-Safe Clock Monitor events also reset the WDT and
postscaler, allowing it to start timing from when execution speed was changed and decreasing the likelihood
of an erroneous time-out.
21.5.2
Clock
Failure
Detected
Clock failure is tested for on the falling edge of the
sample clock. If a sample clock falling edge occurs
while CM is still set, a clock failure has been detected
(Figure 21-5). This causes the following:
• the FSCM generates an oscillator fail interrupt by
setting bit, OSCFIF (PIR2<7>);
• the device clock source is switched to the internal
oscillator block (OSCCON is not updated to show
the current clock source – this is the fail-safe
condition); and
• the WDT is reset.
FSCM AND THE WATCHDOG TIMER
EXITING FAIL-SAFE OPERATION
The fail-safe condition is terminated by either a device
Reset or by entering a power-managed mode. On
Reset, the controller starts the primary clock source
specified in Configuration Register 2H (with the OST
oscillator, start-up delays if running in HS mode). The
INTRC oscillator provides the device clock until the
primary clock source becomes ready (similar to a
Two-Speed Start-up). The clock source is then
switched to the primary clock (indicated by the OSTS
bit in the OSCCON register becoming set). The
Fail-Safe Clock Monitor then resumes monitoring the
peripheral clock.
The primary clock source may never become ready
during start-up. In this case, operation is clocked by the
INTRC oscillator. The OSCCON register will remain in
its Reset state until a power-managed mode is entered.
During switchover, the postscaler frequency from the
internal oscillator block may not be sufficiently stable
for timing sensitive applications. In these cases, it may
be desirable to select another clock configuration and
enter an alternate power-managed mode. This can be
done to attempt a partial recovery or execute a
controlled shutdown. See Section 4.1.4 “Multiple
Sleep Commands” and Section 21.4.1 “Special
Considerations for Using Two-Speed Start-up” for
more details.
© 2009 Microchip Technology Inc.
DS39682E-page 245
PIC18F45J10 FAMILY
FIGURE 21-5:
FSCM TIMING DIAGRAM
Sample Clock
Oscillator
Failure
Device
Clock
Output
CM Output
(Q)
Failure
Detected
OSCFIF
CM Test
Note:
21.5.3
CM Test
CM Test
The device clock is normally at a much higher frequency than the sample clock. The relative frequencies in
this example have been chosen for clarity.
FSCM INTERRUPTS IN
POWER-MANAGED MODES
By entering a power-managed mode, the clock
multiplexor selects the clock source selected by the
OSCCON register. Fail-Safe Monitoring of the
power-managed clock source resumes in the
power-managed mode.
If an oscillator failure occurs during power-managed
operation, the subsequent events depend on whether
or not the oscillator failure interrupt is enabled. If
enabled (OSCFIF = 1), code execution will be clocked
by the INTOSC multiplexor. An automatic transition
back to the failed clock source will not occur.
If the interrupt is disabled, subsequent interrupts while
in Idle mode will cause the CPU to begin executing
instructions while being clocked by the INTOSC
source.
21.5.4
POR OR WAKE-UP FROM SLEEP
The FSCM is designed to detect oscillator failure at any
point after the device has exited Power-on Reset
(POR) or low-power Sleep mode. When the primary
device clock is either EC or INTRC modes, monitoring
can begin immediately following these events.
For HS mode, the situation is somewhat different.
Since the oscillator may require a start-up time considerably longer than the FSCM sample clock time, a false
clock failure may be detected. To prevent this, the
internal oscillator block is automatically configured as
the device clock and functions until the primary clock is
stable (the OST timer has timed out). This is identical
to Two-Speed Start-up mode. Once the primary clock is
stable, the INTRC returns to its role as the FSCM
source.
Note:
The same logic that prevents false oscillator failure interrupts on POR, or wake from
Sleep, will also prevent the detection of
the oscillator’s failure to start at all
following these events. This can be
avoided by monitoring the OSTS bit and
using a timing routine to determine if the
oscillator is taking too long to start. Even
so, no oscillator failure interrupt will be
flagged.
As noted in Section 21.4.1 “Special Considerations
for Using Two-Speed Start-up”, it is also possible to
select another clock configuration and enter an alternate
power-managed mode while waiting for the primary
clock to become stable. When the new power-managed
mode is selected, the primary clock is disabled.
DS39682E-page 246
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
21.6
Program Verification and
Code Protection
For all devices in the PIC18F45J10 family of devices,
the on-chip program memory space is treated as a
single block. Code protection for this block is controlled
by one Configuration bit, CP0. This bit inhibits external
reads and writes to the program memory space. It has
no direct effect in normal execution mode.
21.6.1
CONFIGURATION REGISTER
PROTECTION
The Configuration registers are protected against
untoward changes or reads in two ways. The primary
protection is the write-once feature of the Configuration
bits which prevents reconfiguration once the bit has
been programmed during a power cycle. To safeguard
against unpredictable events, Configuration bit
changes resulting from individual cell-level disruptions
(such as ESD events) will cause a parity error and
trigger a device Reset.
The data for the Configuration registers is derived from
the Flash Configuration Words in program memory.
When the CP0 bit is set, the source data for device
configuration is also protected as a consequence.
© 2009 Microchip Technology Inc.
21.7
In-Circuit Serial Programming
PIC18F45J10 family microcontrollers can be serially
programmed while in the end application circuit. This is
simply done with two lines for clock and data and three
other lines for power, ground and the programming
voltage. This allows customers to manufacture boards
with unprogrammed devices and then program the
microcontroller just before shipping the product. This
also allows the most recent firmware or a custom
firmware to be programmed.
21.8
In-Circuit Debugger
When the DEBUG Configuration bit is programmed to
a ‘0’, the In-Circuit Debugger functionality is enabled.
This function allows simple debugging functions when
used with MPLAB® IDE. When the microcontroller has
this feature enabled, some resources are not available
for general use. Table 21-3 shows which resources are
required by the background debugger.
TABLE 21-3:
DEBUGGER RESOURCES
I/O pins:
RB6, RB7
Stack:
2 levels
Program Memory:
512 bytes
Data Memory:
32 bytes
DS39682E-page 247
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 248
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
22.0
INSTRUCTION SET SUMMARY
PIC18F45J10 family devices incorporate the standard
set of 75 PIC18 core instructions, as well as an extended
set of 8 new instructions, for the optimization of code that
is recursive or that utilizes a software stack. The
extended set is discussed later in this section.
22.1
Standard Instruction Set
The standard PIC18 instruction set adds many
enhancements to the previous PIC® MCU instruction
sets, while maintaining an easy migration from these
PIC MCU instruction sets. Most instructions are a single program memory word (16 bits), but there are four
instructions that require two program memory
locations.
Each single-word instruction is a 16-bit word divided
into an opcode, which specifies the instruction type and
one or more operands, which further specify the
operation of the instruction.
The instruction set is highly orthogonal and is grouped
into four basic categories:
•
•
•
•
Byte-oriented operations
Bit-oriented operations
Literal operations
Control operations
The PIC18 instruction set summary in Table 22-2 lists
byte-oriented, bit-oriented, literal and control
operations. Table 22-1 shows the opcode field
descriptions.
Most byte-oriented instructions have three operands:
1.
2.
3.
The file register (specified by ‘f’)
The destination of the result (specified by ‘d’)
The accessed memory (specified by ‘a’)
The file register designator ‘f’ specifies which file
register is to be used by the instruction. The destination
designator ‘d’ specifies where the result of the operation is to be placed. If ‘d’ is zero, the result is placed in
the WREG register. If ‘d’ is one, the result is placed in
the file register specified in the instruction.
All bit-oriented instructions have three operands:
1.
2.
3.
The file register (specified by ‘f’)
The bit in the file register (specified by ‘b’)
The accessed memory (specified by ‘a’)
The literal instructions may use some of the following
operands:
• A literal value to be loaded into a file register
(specified by ‘k’)
• The desired FSR register to load the literal value
into (specified by ‘f’)
• No operand required
(specified by ‘—’)
The control instructions may use some of the following
operands:
• A program memory address (specified by ‘n’)
• The mode of the CALL or RETURN instructions
(specified by ‘s’)
• The mode of the table read and table write
instructions (specified by ‘m’)
• No operand required
(specified by ‘—’)
All instructions are a single word, except for four
double-word instructions. These instructions were
made double-word to contain the required information
in 32 bits. In the second word, the 4 MSbs are ‘1’s. If
this second word is executed as an instruction (by
itself), it will execute as a NOP.
All single-word instructions are executed in a single
instruction cycle, unless a conditional test is true or the
program counter is changed as a result of the instruction. In these cases, the execution takes two instruction
cycles, with the additional instruction cycle(s) executed
as a NOP.
The double-word instructions execute in two instruction
cycles.
One instruction cycle consists of four oscillator periods.
Thus, for an oscillator frequency of 4 MHz, the normal
instruction execution time is 1 μs. If a conditional test is
true, or the program counter is changed as a result of
an instruction, the instruction execution time is 2 μs.
Two-word branch instructions (if true) would take 3 μs.
Figure 22-1 shows the general formats that the instructions can have. All examples use the convention ‘nnh’
to represent a hexadecimal number.
The Instruction Set Summary, shown in Table 22-2,
lists the standard instructions recognized by the
Microchip Assembler (MPASMTM).
Section 22.1.1 “Standard Instruction Set” provides
a description of each instruction.
The bit field designator ‘b’ selects the number of the bit
affected by the operation, while the file register
designator ‘f’ represents the number of the file in which
the bit is located.
© 2009 Microchip Technology Inc.
DS39682E-page 249
PIC18F45J10 FAMILY
TABLE 22-1:
OPCODE FIELD DESCRIPTIONS
Field
Description
a
RAM access bit
a = 0: RAM location in Access RAM (BSR register is ignored)
a = 1: RAM bank is specified by BSR register
bbb
Bit address within an 8-bit file register (0 to 7).
BSR
Bank Select Register. Used to select the current RAM bank.
C, DC, Z, OV, N
ALU Status bits: Carry, Digit Carry, Zero, Overflow, Negative.
d
Destination select bit
d = 0: store result in WREG
d = 1: store result in file register f
dest
Destination: either the WREG register or the specified register file location.
f
8-bit register file address (00h to FFh) or 2-bit FSR designator (0h to 3h).
fs
12-bit register file address (000h to FFFh). This is the source address.
fd
12-bit register file address (000h to FFFh). This is the destination address.
GIE
Global Interrupt Enable bit.
k
Literal field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value).
label
Label name.
mm
The mode of the TBLPTR register for the table read and table write instructions.
Only used with table read and table write instructions:
*
No change to register (such as TBLPTR with table reads and writes)
*+
Post-Increment register (such as TBLPTR with table reads and writes)
*-
Post-Decrement register (such as TBLPTR with table reads and writes)
Pre-Increment register (such as TBLPTR with table reads and writes)
+*
n
The relative address (2’s complement number) for relative branch instructions or the direct address for
Call/Branch and Return instructions.
PC
Program Counter.
PCL
Program Counter Low Byte.
PCH
Program Counter High Byte.
PCLATH
Program Counter High Byte Latch.
PCLATU
Program Counter Upper Byte Latch.
PD
Power-down bit.
PRODH
Product of Multiply High Byte.
PRODL
Product of Multiply Low Byte.
s
Fast Call/Return mode select bit
s = 0: do not update into/from shadow registers
s = 1: certain registers loaded into/from shadow registers (Fast mode)
TBLPTR
21-bit Table Pointer (points to a program memory location).
TABLAT
8-bit Table Latch.
TO
Time-out bit.
TOS
Top-of-Stack.
u
Unused or unchanged.
WDT
Watchdog Timer.
WREG
Working register (accumulator).
x
Don’t care (‘0’ or ‘1’). The assembler will generate code with x = 0. It is the recommended form of use for
compatibility with all Microchip software tools.
zs
7-bit offset value for indirect addressing of register files (source).
7-bit offset value for indirect addressing of register files (destination).
zd
{
}
Optional argument.
[text]
Indicates an indexed address.
(text)
The contents of text.
[expr]<n>
Specifies bit n of the register indicated by the pointer expr.
→
Assigned to.
< >
Register bit field.
∈
In the set of.
italics
User-defined term (font is Courier New).
DS39682E-page 250
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 22-1:
GENERAL FORMAT FOR INSTRUCTIONS
Byte-oriented file register operations
15
10
9
OPCODE
Example Instruction
8 7
d
0
a
f (FILE #)
ADDWF MYREG, W, B
d = 0 for result destination to be WREG register
d = 1 for result destination to be file register (f)
a = 0 to force Access Bank
a = 1 for BSR to select bank
f = 8-bit file register address
Byte to Byte move operations (2-word)
15
12 11
OPCODE
15
0
f (Source FILE #)
12 11
MOVFF MYREG1, MYREG2
0
f (Destination FILE #)
1111
f = 12-bit file register address
Bit-oriented file register operations
15
12 11
9 8 7
OPCODE b (BIT #) a
0
f (FILE #)
BSF MYREG, bit, B
b = 3-bit position of bit in file register (f)
a = 0 to force Access Bank
a = 1 for BSR to select bank
f = 8-bit file register address
Literal operations
15
8
7
0
OPCODE
k (literal)
MOVLW 7Fh
k = 8-bit immediate value
Control operations
CALL, GOTO and Branch operations
15
8 7
OPCODE
15
0
n<7:0> (literal)
12 11
GOTO Label
0
n<19:8> (literal)
1111
n = 20-bit immediate value
15
8 7
OPCODE
15
S
0
n<7:0> (literal)
12 11
CALL MYFUNC
0
n<19:8> (literal)
1111
S = Fast bit
15
11 10
OPCODE
15
0
n<10:0> (literal)
8 7
OPCODE
© 2009 Microchip Technology Inc.
BRA MYFUNC
0
n<7:0> (literal)
BC MYFUNC
DS39682E-page 251
PIC18F45J10 FAMILY
TABLE 22-2:
PIC18FXXXX INSTRUCTION SET
Mnemonic,
Operands
16-Bit Instruction Word
Description
Cycles
MSb
LSb
Status
Affected
Notes
BYTE-ORIENTED OPERATIONS
ADDWF
ADDWFC
ANDWF
CLRF
COMF
CPFSEQ
CPFSGT
CPFSLT
DECF
DECFSZ
DCFSNZ
INCF
INCFSZ
INFSNZ
IORWF
MOVF
MOVFF
f, d, a
f, d, a
f, d, a
f, a
f, d, a
f, a
f, a
f, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
f, d, a
fs, fd
MOVWF
MULWF
NEGF
RLCF
RLNCF
RRCF
RRNCF
SETF
SUBFWB
f, a
f, a
f, a
f, d, a
f, d, a
f, d, a
f, d, a
f, a
f, d, a
SUBWF
SUBWFB
f, d, a
f, d, a
SWAPF
TSTFSZ
XORWF
f, d, a
f, a
f, d, a
Note 1:
When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an
external device, the data will be written back with a ‘0’.
If this instruction is executed on the TMR0 register (and where applicable, ‘d’ = 1), the prescaler will be cleared if
assigned.
If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second
cycle is executed as a NOP.
Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the
first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory
locations have a valid instruction.
2:
3:
4:
DS39682E-page 252
Add WREG and f
Add WREG and Carry bit to f
AND WREG with f
Clear f
Complement f
Compare f with WREG, Skip =
Compare f with WREG, Skip >
Compare f with WREG, Skip <
Decrement f
Decrement f, Skip if 0
Decrement f, Skip if Not 0
Increment f
Increment f, Skip if 0
Increment f, Skip if Not 0
Inclusive OR WREG with f
Move f
Move fs (source) to 1st Word
fd (destination) 2nd Word
Move WREG to f
Multiply WREG with f
Negate f
Rotate Left f through Carry
Rotate Left f (No Carry)
Rotate Right f through Carry
Rotate Right f (No Carry)
Set f
Subtract f from WREG with
Borrow
Subtract WREG from f
Subtract WREG from f with
Borrow
Swap Nibbles in f
Test f, Skip if 0
Exclusive OR WREG with f
1
1
1
1
1
1 (2 or 3)
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1 (2 or 3)
1 (2 or 3)
1
1
2
C, DC, Z, OV, N
C, DC, Z, OV, N
Z, N
Z
Z, N
None
None
None
C, DC, Z, OV, N
None
None
C, DC, Z, OV, N
None
None
Z, N
Z, N
None
1, 2
1, 2
1,2
2
1, 2
4
4
1, 2
1, 2, 3, 4
1, 2, 3, 4
1, 2
1, 2, 3, 4
4
1, 2
1, 2
1
1
1
1
1
1
1
1
1
1
0010
0010
0001
0110
0001
0110
0110
0110
0000
0010
0100
0010
0011
0100
0001
0101
1100
1111
0110
0000
0110
0011
0100
0011
0100
0110
0101
01da
00da
01da
101a
11da
001a
010a
000a
01da
11da
11da
10da
11da
10da
00da
00da
ffff
ffff
111a
001a
110a
01da
01da
00da
00da
100a
01da
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
1
1
0101
0101
11da
10da
ffff
ffff
ffff C, DC, Z, OV, N
ffff C, DC, Z, OV, N
1, 2
1
1 (2 or 3)
1
0011
0110
0001
10da
011a
10da
ffff
ffff
ffff
ffff None
ffff None
ffff Z, N
4
1, 2
None
None
C, DC, Z, OV, N
C, Z, N
Z, N
C, Z, N
Z, N
None
C, DC, Z, OV, N
1, 2
1, 2
1, 2
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 22-2:
PIC18FXXXX INSTRUCTION SET (CONTINUED)
16-Bit Instruction Word
Mnemonic,
Operands
Description
Cycles
MSb
LSb
Status
Affected
Notes
BIT-ORIENTED OPERATIONS
BCF
BSF
BTFSC
BTFSS
BTG
f, b, a
f, b, a
f, b, a
f, b, a
f, d, a
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
Bit Toggle f
1
1
1 (2 or 3)
1 (2 or 3)
1
1001
1000
1011
1010
0111
bbba
bbba
bbba
bbba
bbba
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
None
None
None
None
None
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
1 (2)
2
1 (2)
2
0010
0110
0011
0111
0101
0001
0100
0nnn
0000
110s
kkkk
0000
0000
1111
kkkk
0000
xxxx
0000
0000
1nnn
0000
0000
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0000
0000
kkkk
kkkk
0000
xxxx
0000
0000
nnnn
1111
0001
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
nnnn
kkkk
kkkk
0100
0111
kkkk
kkkk
0000
xxxx
0110
0101
nnnn
1111
000s
None
None
None
None
None
None
None
None
None
None
1
1
1
1
2
1
2
1110
1110
1110
1110
1110
1110
1110
1101
1110
1110
1111
0000
0000
1110
1111
0000
1111
0000
0000
1101
0000
0000
2
2
1
0000
0000
0000
1100
0000
0000
kkkk
0001
0000
1, 2
1, 2
3, 4
3, 4
1, 2
CONTROL OPERATIONS
BC
BN
BNC
BNN
BNOV
BNZ
BOV
BRA
BZ
CALL
n
n
n
n
n
n
n
n
n
n, s
CLRWDT
DAW
GOTO
—
—
n
NOP
NOP
POP
PUSH
RCALL
RESET
RETFIE
—
—
—
—
n
s
Branch if Carry
Branch if Negative
Branch if Not Carry
Branch if Not Negative
Branch if Not Overflow
Branch if Not Zero
Branch if Overflow
Branch Unconditionally
Branch if Zero
Call subroutine 1st Word
2nd Word
Clear Watchdog Timer
Decimal Adjust WREG
Go to address 1st Word
2nd Word
No Operation
No Operation
Pop Top of Return Stack (TOS)
Push Top of Return Stack (TOS)
Relative Call
Software Device Reset
Return from Interrupt Enable
RETLW
RETURN
SLEEP
k
s
—
Return with Literal in WREG
Return from Subroutine
Go into Standby mode
Note 1:
When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an
external device, the data will be written back with a ‘0’.
If this instruction is executed on the TMR0 register (and where applicable, ‘d’ = 1), the prescaler will be cleared if
assigned.
If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second
cycle is executed as a NOP.
Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the
first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory
locations have a valid instruction.
2:
3:
4:
© 2009 Microchip Technology Inc.
1
1
2
TO, PD
C
None
None
None
None
None
None
All
GIE/GIEH,
PEIE/GIEL
kkkk None
001s None
0011 TO, PD
4
DS39682E-page 253
PIC18F45J10 FAMILY
TABLE 22-2:
PIC18FXXXX INSTRUCTION SET (CONTINUED)
16-Bit Instruction Word
Mnemonic,
Operands
Description
Cycles
MSb
LSb
Status
Affected
Notes
LITERAL OPERATIONS
ADDLW
ANDLW
IORLW
LFSR
k
k
k
f, k
MOVLB
MOVLW
MULLW
RETLW
SUBLW
XORLW
k
k
k
k
k
k
Add Literal and WREG
AND Literal with WREG
Inclusive OR Literal with WREG
Move Literal (12-bit) 2nd Word
to FSR(f)
1st Word
Move Literal to BSR<3:0>
Move Literal to WREG
Multiply Literal with WREG
Return with Literal in WREG
Subtract WREG from Literal
Exclusive OR Literal with WREG
1
1
1
2
1
1
1
2
1
1
0000
0000
0000
1110
1111
0000
0000
0000
0000
0000
0000
1111
1011
1001
1110
0000
0001
1110
1101
1100
1000
1010
kkkk
kkkk
kkkk
00ff
kkkk
0000
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
kkkk
C, DC, Z, OV, N
Z, N
Z, N
None
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
1000
1001
1010
1011
1100
1101
1110
1111
None
None
None
None
None
None
None
None
None
None
None
None
C, DC, Z, OV, N
Z, N
DATA MEMORY ↔ PROGRAM MEMORY OPERATIONS
TBLRD*
TBLRD*+
TBLRD*TBLRD+*
TBLWT*
TBLWT*+
TBLWT*TBLWT+*
Note 1:
2:
3:
4:
Table Read
Table Read with Post-Increment
Table Read with Post-Decrement
Table Read with Pre-Increment
Table Write
Table Write with Post-Increment
Table Write with Post-Decrement
Table Write with Pre-Increment
2
2
When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value
present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an
external device, the data will be written back with a ‘0’.
If this instruction is executed on the TMR0 register (and where applicable, ‘d’ = 1), the prescaler will be cleared if
assigned.
If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second
cycle is executed as a NOP.
Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the
first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory
locations have a valid instruction.
DS39682E-page 254
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
22.1.1
STANDARD INSTRUCTION SET
ADDLW
ADD Literal to W
ADDWF
ADD W to f
Syntax:
ADDLW
Syntax:
ADDWF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(W) + (f) → dest
Status Affected:
N, OV, C, DC, Z
k
Operands:
0 ≤ k ≤ 255
Operation:
(W) + k → W
Status Affected:
N, OV, C, DC, Z
Encoding:
0000
1111
kkkk
kkkk
Description:
The contents of W are added to the
8-bit literal ‘k’ and the result is placed in
W.
Words:
1
Cycles:
1
Encoding:
0010
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write to W
Example:
ADDLW
=
25h
ffff
Words:
1
Cycles:
1
Before Instruction
W
ffff
Add W to register ‘f’. If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the
result is stored back in register ‘f’
(default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
15h
W
= 10h
After Instruction
01da
Description:
Q Cycle Activity:
Decode
f {,d {,a}}
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
ADDWF
REG, 0, 0
Before Instruction
W
=
REG
=
After Instruction
W
REG
Note:
=
=
17h
0C2h
0D9h
0C2h
All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in
symbolic addressing. If a label is used, the instruction format then becomes: {label} instruction argument(s).
© 2009 Microchip Technology Inc.
DS39682E-page 255
PIC18F45J10 FAMILY
ADDWFC
ADD W and Carry bit to f
ANDLW
AND Literal with W
Syntax:
ADDWFC
Syntax:
ANDLW
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
f {,d {,a}}
Operation:
(W) + (f) + (C) → dest
Status Affected:
N,OV, C, DC, Z
Encoding:
0010
Description:
00da
ffff
Add W, the Carry flag and data memory
location ‘f’. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed in data memory location ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Operands:
0 ≤ k ≤ 255
Operation:
(W) .AND. k → W
Status Affected:
N, Z
Encoding:
ffff
k
0000
1011
kkkk
kkkk
Description:
The contents of W are ANDed with the
8-bit literal ‘k’. The result is placed in W.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read literal
‘k’
Process
Data
Write to W
Example:
ANDLW
05Fh
Before Instruction
W
=
After Instruction
W
=
A3h
03h
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
ADDWFC
Before Instruction
Carry bit =
REG
=
W
=
After Instruction
Carry bit =
REG
=
W
=
DS39682E-page 256
REG, 0, 1
1
02h
4Dh
0
02h
50h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
ANDWF
AND W with f
BC
Branch if Carry
Syntax:
ANDWF
Syntax:
BC
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
-128 ≤ n ≤ 127
Operation:
if Carry bit is ‘1’,
(PC) + 2 + 2n → PC
Status Affected:
None
f {,d {,a}}
Operation:
(W) .AND. (f) → dest
Status Affected:
N, Z
Encoding:
0001
Description:
Encoding:
01da
ffff
ffff
The contents of W are ANDed with
register ‘f’. If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
ANDWF
REG, 0, 0
Before Instruction
W
=
REG
=
After Instruction
W
REG
=
=
17h
C2h
02h
C2h
© 2009 Microchip Technology Inc.
n
1110
Description:
0010
nnnn
nnnn
If the Carry bit is ‘1’, then the program
will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
Example:
HERE
Before Instruction
PC
After Instruction
If Carry
PC
If Carry
PC
BC
5
=
address (HERE)
=
=
=
=
1;
address (HERE + 12)
0;
address (HERE + 2)
DS39682E-page 257
PIC18F45J10 FAMILY
BCF
Bit Clear f
BN
Branch if Negative
Syntax:
BCF
Syntax:
BN
Operands:
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operands:
-128 ≤ n ≤ 127
Operation:
if Negative bit is ‘1’,
(PC) + 2 + 2n → PC
Status Affected:
None
f, b {,a}
Operation:
0 → f<b>
Status Affected:
None
Encoding:
Encoding:
1001
Description:
bbba
ffff
ffff
Bit ‘b’ in register ‘f’ is cleared.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
BCF
Before Instruction
FLAG_REG =
After Instruction
FLAG_REG =
DS39682E-page 258
FLAG_REG,
7, 0
n
1110
Description:
0110
nnnn
nnnn
If the Negative bit is ‘1’, then the
program will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
C7h
47h
Example:
HERE
Before Instruction
PC
After Instruction
If Negative
PC
If Negative
PC
BN
Jump
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE + 2)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
BNC
Branch if Not Carry
BNN
Branch if Not Negative
Syntax:
BNC
Syntax:
BNN
n
n
Operands:
-128 ≤ n ≤ 127
Operands:
-128 ≤ n ≤ 127
Operation:
if Carry bit is ‘0’,
(PC) + 2 + 2n → PC
Operation:
if Negative bit is ‘0’,
(PC) + 2 + 2n → PC
Status Affected:
None
Status Affected:
None
Encoding:
1110
0011
nnnn
nnnn
Encoding:
1110
0111
nnnn
nnnn
Description:
If the Carry bit is ‘0’, then the program
will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Description:
If the Negative bit is ‘0’, then the
program will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
Decode
Read literal
‘n’
Process
Data
No
operation
If No Jump:
Example:
If No Jump:
HERE
Before Instruction
PC
After Instruction
If Carry
PC
If Carry
PC
BNC
Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
© 2009 Microchip Technology Inc.
Example:
HERE
Before Instruction
PC
After Instruction
If Negative
PC
If Negative
PC
BNN
Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
DS39682E-page 259
PIC18F45J10 FAMILY
BNOV
Branch if Not Overflow
BNZ
Branch if Not Zero
Syntax:
BNOV
Syntax:
BNZ
n
n
Operands:
-128 ≤ n ≤ 127
Operands:
-128 ≤ n ≤ 127
Operation:
if Overflow bit is ‘0’,
(PC) + 2 + 2n → PC
Operation:
if Zero bit is ‘0’,
(PC) + 2 + 2n → PC
Status Affected:
None
Status Affected:
None
Encoding:
1110
0101
nnnn
nnnn
Encoding:
1110
0001
nnnn
nnnn
Description:
If the Overflow bit is ‘0’, then the
program will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Description:
If the Zero bit is ‘0’, then the program
will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Q Cycle Activity:
If Jump:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
Decode
Read literal
‘n’
Process
Data
No
operation
If No Jump:
If No Jump:
Example:
HERE
Before Instruction
PC
After Instruction
If Overflow
PC
If Overflow
PC
DS39682E-page 260
BNOV Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
Example:
HERE
Before Instruction
PC
After Instruction
If Zero
PC
If Zero
PC
BNZ
Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
BRA
Unconditional Branch
BSF
Bit Set f
Syntax:
BRA
Syntax:
BSF
Operands:
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operation:
1 → f<b>
Status Affected:
None
n
Operands:
-1024 ≤ n ≤ 1023
Operation:
(PC) + 2 + 2n → PC
Status Affected:
None
Encoding:
1101
Description:
0nnn
nnnn
nnnn
Add the 2’s complement number, ‘2n’, to
the PC. Since the PC will have
incremented to fetch the next instruction,
the new address will be PC + 2 + 2n. This
instruction is a two-cycle instruction.
Words:
1
Cycles:
2
Encoding:
1000
Q1
Q2
Q3
Q4
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
Example:
bbba
ffff
ffff
Description:
Bit ‘b’ in register ‘f’ is set.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Decode
f, b {,a}
Q Cycle Activity:
HERE
Before Instruction
PC
After Instruction
PC
BRA
Jump
=
address (HERE)
=
address (Jump)
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
BSF
Before Instruction
FLAG_REG
After Instruction
FLAG_REG
© 2009 Microchip Technology Inc.
FLAG_REG, 7, 1
=
0Ah
=
8Ah
DS39682E-page 261
PIC18F45J10 FAMILY
BTFSC
Bit Test File, Skip if Clear
BTFSS
Bit Test File, Skip if Set
Syntax:
BTFSC f, b {,a}
Syntax:
BTFSS f, b {,a}
Operands:
0 ≤ f ≤ 255
0≤b≤7
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
0≤b<7
a ∈ [0,1]
Operation:
skip if (f<b>) = 0
Operation:
skip if (f<b>) = 1
Status Affected:
None
Status Affected:
None
Encoding:
1011
Description:
bbba
ffff
ffff
Encoding:
1010
If bit ‘b’ in register ‘f’ is ‘0’, then the next
instruction is skipped. If bit ‘b’ is ‘0’, then
the next instruction fetched during the
current instruction execution is discarded
and a NOP is executed instead, making
this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates in
Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh).
See Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Description:
Words:
1
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Cycles:
1(2)
Note:
Q Cycle Activity:
bbba
ffff
ffff
If bit ‘b’ in register ‘f’ is ‘1’, then the next
instruction is skipped. If bit ‘b’ is ‘1’, then
the next instruction fetched during the
current instruction execution is discarded
and a NOP is executed instead, making
this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected. If
‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh).
See Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
Decode
Read
register ‘f’
Process
Data
No
operation
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
If skip:
If skip:
If skip and followed by 2-word instruction:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
FALSE
TRUE
Before Instruction
PC
After Instruction
If FLAG<1>
PC
If FLAG<1>
PC
DS39682E-page 262
BTFSC
:
:
FLAG, 1, 0
=
address (HERE)
=
=
=
=
0;
address (TRUE)
1;
address (FALSE)
Example:
HERE
FALSE
TRUE
Before Instruction
PC
After Instruction
If FLAG<1>
PC
If FLAG<1>
PC
BTFSS
:
:
FLAG, 1, 0
=
address (HERE)
=
=
=
=
0;
address (FALSE)
1;
address (TRUE)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
BTG
Bit Toggle f
BOV
Branch if Overflow
Syntax:
BTG f, b {,a}
Syntax:
BOV
Operands:
0 ≤ f ≤ 255
0≤b<7
a ∈ [0,1]
Operands:
-128 ≤ n ≤ 127
Operation:
if Overflow bit is ‘1’,
(PC) + 2 + 2n → PC
Status Affected:
None
Operation:
(f<b>) → f<b>
Status Affected:
None
Encoding:
0111
Description:
Encoding:
bbba
ffff
ffff
Bit ‘b’ in data memory location ‘f’ is
inverted.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
n
1110
0100
nnnn
nnnn
Description:
If the Overflow bit is ‘1’, then the
program will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Q Cycle Activity:
If Jump:
Words:
1
Q1
Q2
Q3
Q4
Cycles:
1
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
BTG
PORTC,
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
4, 0
Before Instruction:
PORTC =
0111 0101 [75h]
After Instruction:
PORTC =
0110 0101 [65h]
© 2009 Microchip Technology Inc.
If No Jump:
Example:
HERE
Before Instruction
PC
After Instruction
If Overflow
PC
If Overflow
PC
BOV
Jump
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE + 2)
DS39682E-page 263
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BZ
Branch if Zero
CALL
Subroutine Call
Syntax:
BZ
Syntax:
CALL k {,s}
n
Operands:
-128 ≤ n ≤ 127
Operands:
Operation:
if Zero bit is ‘1’,
(PC) + 2 + 2n → PC
0 ≤ k ≤ 1048575
s ∈ [0,1]
Operation:
Status Affected:
None
(PC) + 4 → TOS,
k → PC<20:1>;
if s = 1,
(W) → WS,
(STATUS) → STATUSS,
(BSR) → BSRS
Status Affected:
None
Encoding:
1110
Description:
0000
nnnn
nnnn
If the Zero bit is ‘1’, then the program
will branch.
The 2’s complement number, ‘2n’, is
added to the PC. Since the PC will
have incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
Words:
1
Cycles:
1(2)
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
Q1
Q2
Q3
Q4
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
Example:
HERE
Before Instruction
PC
After Instruction
If Zero
PC
If Zero
PC
DS39682E-page 264
BZ
k7kkk
kkkk
110s
k19kkk
Subroutine call of entire 2-Mbyte
memory range. First, return address
(PC + 4) is pushed onto the return
stack. If ‘s’ = 1, the W, STATUS and
BSR registers are also pushed into their
respective shadow registers, WS,
STATUSS and BSRS. If ‘s’ = 0, no
update occurs (default). Then, the
20-bit value ‘k’ is loaded into PC<20:1>.
CALL is a two-cycle instruction.
Words:
2
Cycles:
2
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
Read literal PUSH PC to
‘k’<7:0>,
stack
Jump
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE + 2)
kkkk0
kkkk8
Description:
Q Cycle Activity:
If Jump:
Decode
1110
1111
No
operation
Example:
No
operation
HERE
Before Instruction
PC
=
After Instruction
PC
=
TOS
=
WS
=
BSRS
=
STATUSS =
No
operation
CALL
Read literal
‘k’<19:8>,
Write to PC
No
operation
THERE, 1
address (HERE)
address (THERE)
address (HERE + 4)
W
BSR
STATUS
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
CLRF
Clear f
Syntax:
CLRF
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
f {,a}
Operation:
000h → f,
1→Z
Status Affected:
Z
Encoding:
0110
Description:
101a
ffff
ffff
Clears the contents of the specified
register.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
CLRF
Before Instruction
FLAG_REG
After Instruction
FLAG_REG
Clear Watchdog Timer
Syntax:
CLRWDT
Operands:
None
Operation:
000h → WDT,
000h → WDT postscaler,
1 → TO,
1 → PD
Status Affected:
TO, PD
Encoding:
FLAG_REG, 1
=
5Ah
=
00h
© 2009 Microchip Technology Inc.
0000
0000
0000
0100
Description:
CLRWDT instruction resets the
Watchdog Timer. It also resets the
postscaler of the WDT. Status bits, TO
and PD, are set.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
Process
Data
No
operation
Example:
Q Cycle Activity:
Example:
CLRWDT
CLRWDT
Before Instruction
WDT Counter
After Instruction
WDT Counter
WDT Postscaler
TO
PD
=
?
=
=
=
=
00h
0
1
1
DS39682E-page 265
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COMF
Complement f
CPFSEQ
Compare f with W, Skip if f = W
Syntax:
COMF
Syntax:
CPFSEQ
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) – (W),
skip if (f) = (W)
(unsigned comparison)
Status Affected:
None
f {,d {,a}}
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
Operation:
(f) → dest
Status Affected:
N, Z
Encoding:
0001
11da
ffff
ffff
Description:
The contents of register ‘f’ are
complemented. If ‘d’ is ‘0’, the result is
stored in W. If ‘d’ is ‘1’, the result is
stored back in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Encoding:
0110
f {,a}
001a
ffff
ffff
Description:
Compares the contents of data memory
location ‘f’ to the contents of W by
performing an unsigned subtraction.
If ‘f’ = W, then the fetched instruction is
discarded and a NOP is executed
instead, making this a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Example:
COMF
Before Instruction
REG
=
After Instruction
REG
=
W
=
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
REG, 0, 0
13h
If skip:
13h
ECh
Q1
Q2
Q3
No
No
No
operation
operation
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
No
No
No
operation
operation
operation
No
No
No
operation
operation
operation
Example:
DS39682E-page 266
HERE
NEQUAL
EQUAL
Q4
No
operation
Q4
No
operation
No
operation
CPFSEQ REG, 0
:
:
Before Instruction
PC Address
W
REG
After Instruction
=
=
=
HERE
?
?
If REG
PC
If REG
PC
=
=
≠
=
W;
Address (EQUAL)
W;
Address (NEQUAL)
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
CPFSGT
Compare f with W, Skip if f > W
CPFSLT
Compare f with W, Skip if f < W
Syntax:
CPFSGT
Syntax:
CPFSLT
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) – (W),
skip if (f) > (W)
(unsigned comparison)
Operation:
(f) – (W),
skip if (f) < (W)
(unsigned comparison)
Status Affected:
None
Status Affected:
None
Encoding:
0110
Description:
f {,a}
010a
ffff
ffff
Compares the contents of data memory
location ‘f’ to the contents of the W by
performing an unsigned subtraction.
If the contents of ‘f’ are greater than the
contents of WREG, then the fetched
instruction is discarded and a NOP is
executed instead, making this a
two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Encoding:
Q2
Read
register ‘f’
Q3
Process
Data
Q4
No
operation
Q1
Q2
Q3
No
No
No
operation
operation
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
No
No
No
operation
operation
operation
No
No
No
operation
operation
operation
Q4
No
operation
Example:
HERE
NGREATER
GREATER
CPFSGT REG, 0
:
:
Before Instruction
PC
W
After Instruction
=
=
Address (HERE)
?
If REG
PC
If REG
PC
>
=
≤
=
W;
Address (GREATER)
W;
Address (NGREATER)
© 2009 Microchip Technology Inc.
000a
ffff
ffff
Compares the contents of data memory
location ‘f’ to the contents of W by
performing an unsigned subtraction.
If the contents of ‘f’ are less than the
contents of W, then the fetched
instruction is discarded and a NOP is
executed instead, making this a
two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
Words:
1
Cycles:
1(2)
Note:
3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip:
If skip and followed by 2-word instruction:
If skip:
Q4
No
operation
No
operation
0110
Description:
Q Cycle Activity:
Q1
Decode
f {,a}
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
NLESS
LESS
Before Instruction
PC
W
After Instruction
If REG
PC
If REG
PC
CPFSLT REG, 1
:
:
=
=
Address (HERE)
?
<
=
≥
=
W;
Address (LESS)
W;
Address (NLESS)
DS39682E-page 267
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DAW
Decimal Adjust W Register
DECF
Decrement f
Syntax:
DAW
Syntax:
DECF f {,d {,a}}
Operands:
None
Operands:
Operation:
If [W<3:0> > 9] or [DC = 1] then,
(W<3:0>) + 6 → W<3:0>;
else,
(W<3:0>) → W<3:0>
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – 1 → dest
Status Affected:
C, DC, N, OV, Z
If [W<7:4> + DC > 9] or [C = 1] then,
(W<7:4>) + 6 + DC → W<7:4>;
else,
(W<7:4>) + DC → W<7:4>
Status Affected:
Encoding:
0000
0000
0000
DAW adjusts the eight-bit value in W,
resulting from the earlier addition of two
variables (each in packed BCD format)
and produces a correct packed BCD
result.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register W
Process
Data
Write
W
Example 1:
DAW
=
=
=
A5h
0
0
05h
1
0
ffff
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Before Instruction
W
=
C
=
DC
=
After Instruction
ffff
Decrement register ‘f’. If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the
result is stored back in register ‘f’
(default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
0111
Description:
01da
Description:
C
Encoding:
W
C
DC
Example 2:
0000
Example:
DECF
Before Instruction
CNT
=
Z
=
After Instruction
CNT
=
Z
=
CNT,
1, 0
01h
0
00h
1
Before Instruction
W
=
C
=
DC
=
After Instruction
W
C
DC
=
=
=
DS39682E-page 268
CEh
0
0
34h
1
0
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
DECFSZ
Decrement f, Skip if 0
DCFSNZ
Decrement f, Skip if Not 0
Syntax:
DECFSZ f {,d {,a}}
Syntax:
DCFSNZ
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – 1 → dest,
skip if result = 0
Operation:
(f) – 1 → dest,
skip if result ≠ 0
Status Affected:
None
Status Affected:
None
Encoding:
0010
11da
ffff
ffff
Description:
The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If the result is ‘0’, the next instruction,
which is already fetched, is discarded
and a NOP is executed instead, making
it a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Encoding:
0100
Description:
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
Words:
1
Cycles:
1(2)
Note:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
HERE
DECFSZ
GOTO
Example:
CNT, 1, 1
LOOP
CONTINUE
Before Instruction
PC
=
After Instruction
CNT
=
If CNT
=
PC =
If CNT
≠
PC =
Address (HERE)
CNT – 1
0;
Address (CONTINUE)
0;
Address (HERE + 2)
© 2009 Microchip Technology Inc.
ffff
ffff
3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip:
If skip and followed by 2-word instruction:
11da
The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If the result is not ‘0’, the next
instruction, which is already fetched, is
discarded and a NOP is executed
instead, making it a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Q Cycle Activity:
Q1
f {,d {,a}}
If skip:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
ZERO
NZERO
Before Instruction
TEMP
After Instruction
TEMP
If TEMP
PC
If TEMP
PC
DCFSNZ
:
:
TEMP, 1, 0
=
?
=
=
=
≠
=
TEMP – 1,
0;
Address (ZERO)
0;
Address (NZERO)
DS39682E-page 269
PIC18F45J10 FAMILY
GOTO
Unconditional Branch
INCF
Increment f
Syntax:
GOTO k
Syntax:
INCF
Operands:
0 ≤ k ≤ 1048575
Operands:
Operation:
k → PC<20:1>
Status Affected:
None
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1 → dest
Status Affected:
C, DC, N, OV, Z
Encoding:
1st word (k<7:0>)
2nd word(k<19:8>)
1110
1111
1111
k19kkk
k7kkk
kkkk
kkkk0
kkkk8
Description:
GOTO allows an unconditional branch
anywhere within entire
2-Mbyte memory range. The 20-bit
value ‘k’ is loaded into PC<20:1>. GOTO
is always a two-cycle instruction.
Words:
2
Cycles:
2
Encoding:
0010
Q1
Q2
Q3
Q4
Read literal
‘k’<7:0>,
No
operation
Read literal
‘k’<19:8>,
Write to PC
No
operation
No
operation
No
operation
No
operation
Example:
GOTO THERE
After Instruction
PC =
Address (THERE)
ffff
ffff
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
INCF
Before Instruction
CNT
=
Z
=
C
=
DC
=
After Instruction
CNT
=
Z
=
C
=
DC
=
DS39682E-page 270
10da
Description:
Q Cycle Activity:
Decode
f {,d {,a}}
CNT, 1, 0
FFh
0
?
?
00h
1
1
1
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
INCFSZ
Increment f, Skip if 0
INFSNZ
Syntax:
INCFSZ
Syntax:
INFSNZ
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
f {,d {,a}}
Increment f, Skip if Not 0
f {,d {,a}}
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
Operation:
(f) + 1 → dest,
skip if result = 0
Operation:
(f) + 1 → dest,
skip if result ≠ 0
Status Affected:
None
Status Affected:
None
Encoding:
0011
11da
ffff
ffff
Encoding:
0100
Description:
ffff
ffff
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If the result is not ‘0’, the next
instruction, which is already fetched, is
discarded and a NOP is executed
instead, making it a two-cycle
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Description:
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If the result is ‘0’, the next instruction,
which is already fetched, is discarded
and a NOP is executed instead, making
it a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Cycles:
1(2)
Note:
Q Cycle Activity:
10da
3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Decode
Read
register ‘f’
Process
Data
Write to
destination
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
If skip:
If skip:
If skip and followed by 2-word instruction:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
NZERO
ZERO
Before Instruction
PC
=
After Instruction
CNT
=
If CNT
=
PC
=
If CNT
≠
PC
=
INCFSZ
:
:
Address (HERE)
CNT + 1
0;
Address (ZERO)
0;
Address (NZERO)
© 2009 Microchip Technology Inc.
CNT, 1, 0
Example:
HERE
ZERO
NZERO
Before Instruction
PC
=
After Instruction
REG
=
≠
If REG
PC
=
If REG
=
PC
=
INFSNZ
REG, 1, 0
Address (HERE)
REG + 1
0;
Address (NZERO)
0;
Address (ZERO)
DS39682E-page 271
PIC18F45J10 FAMILY
IORLW
Inclusive OR Literal with W
IORWF
Inclusive OR W with f
Syntax:
IORLW k
Syntax:
IORWF
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
(W) .OR. k → W
Status Affected:
N, Z
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(W) .OR. (f) → dest
Status Affected:
N, Z
Encoding:
0000
1001
kkkk
kkkk
Description:
The contents of W are ORed with the
eight-bit literal ‘k’. The result is placed in
W.
Words:
1
Cycles:
1
Encoding:
0001
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write to W
Example:
IORLW
W
=
ffff
Words:
1
Cycles:
1
35h
9Ah
BFh
ffff
Inclusive OR W with register ‘f’. If ‘d’ is
‘0’, the result is placed in W. If ‘d’ is ‘1’,
the result is placed back in register ‘f’
(default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Before Instruction
W
=
After Instruction
00da
Description:
Q Cycle Activity:
Decode
f {,d {,a}}
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
IORWF
Before Instruction
RESULT =
W
=
After Instruction
RESULT =
W
=
DS39682E-page 272
RESULT, 0, 1
13h
91h
13h
93h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
LFSR
Load FSR
MOVF
Move f
Syntax:
LFSR f, k
Syntax:
MOVF
Operands:
0≤f≤2
0 ≤ k ≤ 4095
Operands:
Operation:
k → FSRf
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Status Affected:
None
Operation:
f → dest
Status Affected:
N, Z
Encoding:
1110
1111
1110
0000
00ff
k7kkk
k11kkk
kkkk
Description:
The 12-bit literal ‘k’ is loaded into the
File Select Register pointed to by ‘f’.
Words:
2
Cycles:
2
Encoding:
0101
Q1
Q2
Q3
Q4
Read literal
‘k’ MSB
Process
Data
Write
literal ‘k’
MSB to
FSRfH
Decode
Read literal
‘k’ LSB
Process
Data
Write literal
‘k’ to FSRfL
Example:
After Instruction
FSR2H
FSR2L
03h
ABh
ffff
ffff
The contents of register ‘f’ are moved to
a destination dependent upon the
status of ‘d’. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
Location ‘f’ can be anywhere in the
256-byte bank.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
LFSR 2, 3ABh
=
=
00da
Description:
Q Cycle Activity:
Decode
f {,d {,a}}
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write W
Example:
MOVF
Before Instruction
REG
W
After Instruction
REG
W
© 2009 Microchip Technology Inc.
REG, 0, 0
=
=
22h
FFh
=
=
22h
22h
DS39682E-page 273
PIC18F45J10 FAMILY
MOVFF
Move f to f
MOVLB
Move Literal to Low Nibble in BSR
Syntax:
MOVFF fs,fd
Syntax:
MOVLW k
Operands:
0 ≤ fs ≤ 4095
0 ≤ fd ≤ 4095
Operands:
0 ≤ k ≤ 255
Operation:
k → BSR
None
Operation:
(fs) → fd
Status Affected:
Status Affected:
None
Encoding:
Encoding:
1st word (source)
2nd word (destin.)
1100
1111
Description:
ffff
ffff
ffff
ffff
ffffs
ffffd
The contents of source register ‘fs’ are
moved to destination register ‘fd’.
Location of source ‘fs’ can be anywhere
in the 4096-byte data space (000h to
FFFh) and location of destination ‘fd’
can also be anywhere from 000h to
FFFh.
Either source or destination can be W
(a useful special situation).
MOVFF is particularly useful for
transferring a data memory location to a
peripheral register (such as the transmit
buffer or an I/O port).
The MOVFF instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register.
Words:
2
Cycles:
2 (3)
0000
0001
kkkk
kkkk
Description:
The eight-bit literal ‘k’ is loaded into the
Bank Select Register (BSR). The value
of BSR<7:4> always remains ‘0’,
regardless of the value of k7:k4.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal ‘k’
Process
Data
Write literal
‘k’ to BSR
MOVLB
5
Example:
Before Instruction
BSR Register =
After Instruction
BSR Register =
02h
05h
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
(src)
Process
Data
No
operation
Decode
No
operation
No
operation
Write
register ‘f’
(dest)
No dummy
read
Example:
MOVFF
Before Instruction
REG1
REG2
After Instruction
REG1
REG2
DS39682E-page 274
REG1, REG2
=
=
33h
11h
=
=
33h
33h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
MOVLW
Move Literal to W
MOVWF
Move W to f
Syntax:
MOVLW k
Syntax:
MOVWF
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
k→W
0 ≤ f ≤ 255
a ∈ [0,1]
Status Affected:
None
Encoding:
0000
Description:
1110
kkkk
kkkk
The eight-bit literal ‘k’ is loaded into W.
Words:
1
Cycles:
1
Operation:
(W) → f
Status Affected:
None
Encoding:
0110
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write to W
Example:
MOVLW
=
ffff
ffff
Move data from W to register ‘f’.
Location ‘f’ can be anywhere in the
256-byte bank.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
5Ah
After Instruction
W
111a
Description:
Q Cycle Activity:
Decode
f {,a}
5Ah
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
MOVWF
REG, 0
Before Instruction
W
=
REG
=
After Instruction
W
REG
© 2009 Microchip Technology Inc.
=
=
4Fh
FFh
4Fh
4Fh
DS39682E-page 275
PIC18F45J10 FAMILY
MULLW
Multiply Literal with W
MULWF
Multiply W with f
Syntax:
MULLW
Syntax:
MULWF
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(W) x (f) → PRODH:PRODL
Status Affected:
None
k
Operands:
0 ≤ k ≤ 255
Operation:
(W) x k → PRODH:PRODL
Status Affected:
None
Encoding:
0000
Description:
1101
kkkk
kkkk
An unsigned multiplication is carried
out between the contents of W and the
8-bit literal ‘k’. The 16-bit result is
placed in the PRODH:PRODL register
pair. PRODH contains the high byte.
W is unchanged.
None of the Status flags are affected.
Note that neither overflow nor carry is
possible in this operation. A zero result
is possible but not detected.
Words:
1
Cycles:
1
Encoding:
0000
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write
registers
PRODH:
PRODL
Example:
MULLW
W
PRODH
PRODL
After Instruction
W
PRODH
PRODL
=
=
=
E2h
?
?
=
=
=
E2h
ADh
08h
ffff
ffff
An unsigned multiplication is carried
out between the contents of W and the
register file location ‘f’. The 16-bit
result is stored in the PRODH:PRODL
register pair. PRODH contains the
high byte. Both W and ‘f’ are
unchanged.
None of the Status flags are affected.
Note that neither overflow nor carry is
possible in this operation. A zero
result is possible but not detected.
If ‘a’ is ‘0’, the Access Bank is
selected. If ‘a’ is ‘1’, the BSR is used
to select the GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction
operates in Indexed Literal Offset
Addressing mode whenever
f ≤ 95 (5Fh). See Section 22.2.3
“Byte-Oriented and Bit-Oriented
Instructions in Indexed Literal Offset
Mode” for details.
Words:
1
Cycles:
1
0C4h
Before Instruction
001a
Description:
Q Cycle Activity:
Decode
f {,a}
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
registers
PRODH:
PRODL
Example:
MULWF
REG, 1
Before Instruction
W
REG
PRODH
PRODL
After Instruction
W
REG
PRODH
PRODL
DS39682E-page 276
=
=
=
=
C4h
B5h
?
?
=
=
=
=
C4h
B5h
8Ah
94h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
NEGF
Negate f
NOP
No Operation
Syntax:
NEGF
Syntax:
NOP
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
f {,a}
Operands:
None
Operation:
No operation
None
Operation:
(f)+1→f
Status Affected:
Status Affected:
N, OV, C, DC, Z
Encoding:
Encoding:
0110
Description:
110a
ffff
Location ‘f’ is negated using two’s
complement. The result is placed in the
data memory location ‘f’.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
0000
1111
ffff
0000
xxxx
Description:
No operation.
Words:
1
Cycles:
1
0000
xxxx
0000
xxxx
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
No
operation
No
operation
Example:
None.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
NEGF
Before Instruction
REG
=
After Instruction
REG
=
REG, 1
0011 1010 [3Ah]
1100 0110 [C6h]
© 2009 Microchip Technology Inc.
DS39682E-page 277
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POP
Pop Top of Return Stack
PUSH
Push Top of Return Stack
Syntax:
POP
Syntax:
PUSH
Operands:
None
Operands:
None
Operation:
(TOS) → bit bucket
Operation:
(PC + 2) → TOS
Status Affected:
None
Status Affected:
None
Encoding:
0000
0000
0000
0110
Description:
The TOS value is pulled off the return
stack and is discarded. The TOS value
then becomes the previous value that
was pushed onto the return stack.
This instruction is provided to enable
the user to properly manage the return
stack to incorporate a software stack.
Words:
1
Cycles:
1
Encoding:
0000
0101
The PC + 2 is pushed onto the top of
the return stack. The previous TOS
value is pushed down on the stack.
This instruction allows implementing a
software stack by modifying TOS and
then pushing it onto the return stack.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
POP TOS
value
No
operation
POP
GOTO
NEW
Q1
Q2
Q3
Q4
Decode
PUSH
PC + 2 onto
return stack
No
operation
No
operation
Example:
Before Instruction
TOS
Stack (1 level down)
=
=
0031A2h
014332h
After Instruction
TOS
PC
=
=
014332h
NEW
DS39682E-page 278
0000
Description:
Q Cycle Activity:
Example:
0000
PUSH
Before Instruction
TOS
PC
=
=
345Ah
0124h
After Instruction
PC
TOS
Stack (1 level down)
=
=
=
0126h
0126h
345Ah
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
RCALL
Relative Call
RESET
Reset
Syntax:
RCALL
Syntax:
RESET
n
Operands:
-1024 ≤ n ≤ 1023
Operands:
None
Operation:
(PC) + 2 → TOS,
(PC) + 2 + 2n → PC
Operation:
Reset all registers and flags that are
affected by a MCLR Reset.
Status Affected:
None
Status Affected:
All
Encoding:
1101
Description:
1nnn
nnnn
nnnn
Subroutine call with a jump up to 1K
from the current location. First, return
address (PC + 2) is pushed onto the
stack. Then, add the 2’s complement
number, ‘2n’, to the PC. Since the PC
will have incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is a
two-cycle instruction.
Words:
1
Cycles:
2
Encoding:
0000
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
1111
1111
This instruction provides a way to
execute a MCLR Reset in software.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Start
Reset
No
operation
No
operation
Example:
Q Cycle Activity:
0000
Description:
After Instruction
Registers =
Flags*
=
RESET
Reset Value
Reset Value
PUSH PC to
stack
No
operation
Example:
No
operation
HERE
RCALL Jump
Before Instruction
PC =
Address (HERE)
After Instruction
PC =
Address (Jump)
TOS =
Address (HERE + 2)
© 2009 Microchip Technology Inc.
DS39682E-page 279
PIC18F45J10 FAMILY
RETFIE
Return from Interrupt
RETLW
Return Literal to W
Syntax:
RETFIE {s}
Syntax:
RETLW k
Operands:
s ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
(TOS) → PC,
1 → GIE/GIEH or PEIE/GIEL;
if s = 1,
(WS) → W,
(STATUSS) → STATUS,
(BSRS) → BSR,
PCLATU, PCLATH are unchanged
Operation:
k → W,
(TOS) → PC,
PCLATU, PCLATH are unchanged
Status Affected:
None
Status Affected:
0000
0000
0001
1
Cycles:
2
Q Cycle Activity:
Q2
Q3
Q4
Decode
No
operation
No
operation
POP PC
from stack
Set GIEH or
GIEL
No
operation
RETFIE
After Interrupt
PC
W
BSR
STATUS
GIE/GIEH, PEIE/GIEL
DS39682E-page 280
kkkk
kkkk
W is loaded with the eight-bit literal ‘k’.
The program counter is loaded from the
top of the stack (the return address).
The high address latch (PCLATH)
remains unchanged.
Words:
1
Cycles:
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal ‘k’
Process
Data
POP PC
from stack,
Write to W
No
operation
No
operation
No
operation
No
operation
Example:
Q1
Example:
1100
Description:
000s
Return from interrupt. Stack is popped
and Top-of-Stack (TOS) is loaded into
the PC. Interrupts are enabled by
setting either the high or low-priority
global interrupt enable bit. If ‘s’ = 1, the
contents of the shadow registers, WS,
STATUSS and BSRS, are loaded into
their corresponding registers, W,
STATUS and BSR. If ‘s’ = 0, no update
of these registers occurs (default).
Words:
No
operation
0000
GIE/GIEH, PEIE/GIEL.
Encoding:
Description:
Encoding:
No
operation
No
operation
1
=
=
=
=
=
TOS
WS
BSRS
STATUSS
1
CALL TABLE ;
;
;
;
:
TABLE
ADDWF PCL ;
RETLW k0
;
RETLW k1
;
:
:
RETLW kn
;
Before Instruction
W
=
After Instruction
W
=
W contains table
offset value
W now has
table value
W = offset
Begin table
End of table
07h
value of kn
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
RETURN
Return from Subroutine
RLCF
Rotate Left f through Carry
Syntax:
RETURN {s}
Syntax:
RLCF
Operands:
s ∈ [0,1]
Operands:
Operation:
(TOS) → PC;
if s = 1,
(WS) → W,
(STATUSS) → STATUS,
(BSRS) → BSR,
PCLATU, PCLATH are unchanged
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f<n>) → dest<n + 1>,
(f<7>) → C,
(C) → dest<0>
Status Affected:
C, N, Z
Status Affected:
None
Encoding:
0000
Encoding:
0000
0001
001s
Description:
Return from subroutine. The stack is
popped and the top of the stack (TOS)
is loaded into the program counter. If
‘s’= 1, the contents of the shadow
registers, WS, STATUSS and BSRS,
are loaded into their corresponding
registers, W, STATUS and BSR. If
‘s’ = 0, no update of these registers
occurs (default).
Words:
1
Cycles:
2
0011
Description:
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
Process
Data
POP PC
from stack
No
operation
No
operation
No
operation
No
operation
f {,d {,a}}
01da
ffff
ffff
The contents of register ‘f’ are rotated
one bit to the left through the Carry
flag. If ‘d’ is ‘0’, the result is placed in
W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is
selected. If ‘a’ is ‘1’, the BSR is used to
select the GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction
operates in Indexed Literal Offset
Addressing mode whenever
f ≤ 95 (5Fh). See Section 22.2.3
“Byte-Oriented and Bit-Oriented
Instructions in Indexed Literal Offset
Mode” for details.
register f
C
Words:
1
Cycles:
1
Q Cycle Activity:
Example:
RETURN
After Instruction:
PC = TOS
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
Before Instruction
REG
=
C
=
After Instruction
REG
=
W
=
C
=
© 2009 Microchip Technology Inc.
RLCF
REG, 0, 0
1110 0110
0
1110 0110
1100 1100
1
DS39682E-page 281
PIC18F45J10 FAMILY
RLNCF
Rotate Left f (No Carry)
RRCF
Rotate Right f through Carry
Syntax:
RLNCF
Syntax:
RRCF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f<n>) → dest<n + 1>,
(f<7>) → dest<0>
Operation:
Status Affected:
N, Z
(f<n>) → dest<n – 1>,
(f<0>) → C,
(C) → dest<7>
Status Affected:
C, N, Z
Encoding:
0100
Description:
f {,d {,a}}
01da
ffff
ffff
The contents of register ‘f’ are rotated
one bit to the left. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
stored back in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Encoding:
0011
Description:
register f
Words:
1
Cycles:
1
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Before Instruction
REG
=
After Instruction
REG
=
DS39682E-page 282
00da
RLNCF
Words:
1
Cycles:
1
0101 0111
ffff
register f
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
RRCF
REG, 0, 0
REG, 1, 0
1010 1011
ffff
The contents of register ‘f’ are rotated
one bit to the right through the Carry
flag. If ‘d’ is ‘0’, the result is placed in W.
If ‘d’ is ‘1’, the result is placed back in
register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
C
Q Cycle Activity:
Example:
f {,d {,a}}
Example:
Before Instruction
REG
=
C
=
After Instruction
REG
=
W
=
C
=
1110 0110
0
1110 0110
0111 0011
0
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
RRNCF
Rotate Right f (No Carry)
SETF
Syntax:
RRNCF
Syntax:
SETF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
FFh → f
Operation:
(f<n>) → dest<n – 1>,
(f<0>) → dest<7>
Status Affected:
None
Status Affected:
Encoding:
N, Z
Encoding:
0100
Description:
f {,d {,a}}
00da
ffff
ffff
The contents of register ‘f’ are rotated
one bit to the right. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank will be
selected, overriding the BSR value. If ‘a’
is ‘1’, then the bank will be selected as
per the BSR value (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
register f
Words:
1
Cycles:
1
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
RRNCF
Before Instruction
REG
=
After Instruction
REG
=
Example 2:
0110
100a
ffff
ffff
The contents of the specified register
are set to FFh.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
SETF
Before Instruction
REG
After Instruction
REG
REG, 1
=
5Ah
=
FFh
REG, 1, 0
1101 0111
1110 1011
RRNCF
Before Instruction
W
=
REG
=
After Instruction
W
=
REG
=
f {,a}
Description:
Example:
Q Cycle Activity:
Example 1:
Set f
REG, 0, 0
?
1101 0111
1110 1011
1101 0111
© 2009 Microchip Technology Inc.
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SLEEP
Enter Sleep mode
SUBFWB
Subtract f from W with Borrow
Syntax:
SLEEP
Syntax:
SUBFWB
Operands:
None
Operands:
Operation:
00h → WDT,
0 → WDT postscaler,
1 → TO,
0 → PD
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(W) – (f) – (C) → dest
Status Affected:
N, OV, C, DC, Z
Status Affected:
TO, PD
Encoding:
0000
Encoding:
0000
0000
0011
Description:
The Power-Down status bit (PD) is
cleared. The Time-out status bit (TO)
is set. Watchdog Timer and its
postscaler are cleared.
The processor is put into Sleep mode
with the oscillator stopped.
Words:
1
Cycles:
1
0101
Q1
Q2
Q3
Q4
No
operation
Process
Data
Go to
Sleep
Example:
SLEEP
Before Instruction
TO =
?
?
PD =
After Instruction
1†
TO =
0
PD =
† If WDT causes wake-up, this bit is cleared.
DS39682E-page 284
01da
ffff
ffff
Description:
Subtract register ‘f’ and Carry flag
(borrow) from W (2’s complement
method). If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored in
register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is
selected. If ‘a’ is ‘1’, the BSR is used
to select the GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction
operates in Indexed Literal Offset
Addressing mode whenever
f ≤ 95 (5Fh). See Section 22.2.3
“Byte-Oriented and Bit-Oriented
Instructions in Indexed Literal Offset
Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Decode
f {,d {,a}}
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
SUBFWB
REG, 1, 0
Example 1:
Before Instruction
REG
=
3
W
=
2
C
=
1
After Instruction
REG
=
FF
W
=
2
C
=
0
Z
=
0
N
=
1 ; result is negative
SUBFWB
REG, 0, 0
Example 2:
Before Instruction
REG
=
2
W
=
5
C
=
1
After Instruction
REG
=
2
W
=
3
C
=
1
Z
=
0
N
=
0 ; result is positive
SUBFWB
REG, 1, 0
Example 3:
Before Instruction
REG
=
1
W
=
2
C
=
0
After Instruction
REG
=
0
W
=
2
C
=
1
Z
=
1 ; result is zero
N
=
0
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
SUBLW
Subtract W from Literal
SUBWF
Subtract W from f
Syntax:
SUBLW k
Syntax:
SUBWF
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
k – (W) → W
Status Affected:
N, OV, C, DC, Z
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – (W) → dest
Status Affected:
N, OV, C, DC, Z
Encoding:
0000
1000
kkkk
kkkk
Description
W is subtracted from the eight-bit
literal ‘k’. The result is placed in W.
Words:
1
Cycles:
1
Encoding:
0101
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write to W
Example 1:
Before Instruction
W
=
C
=
After Instruction
W
=
C
=
Z
=
N
=
Example 2:
Before Instruction
W
=
C
=
After Instruction
W
=
C
=
Z
=
N
=
Example 3:
Before Instruction
W
=
C
=
After Instruction
W
=
C
=
Z
=
N
=
SUBLW
02h
1
Cycles:
1
Q Cycle Activity:
02h
?
00h
1
; result is zero
1
0
SUBLW
ffff
Words:
01h
?
SUBLW
ffff
Subtract W from register ‘f’ (2’s
complement method). If ‘d’ is ‘0’, the
result is stored in W. If ‘d’ is ‘1’, the
result is stored back in register ‘f’
(default).
If ‘a’ is ‘0’, the Access Bank is
selected. If ‘a’ is ‘1’, the BSR is used
to select the GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction
operates in Indexed Literal Offset
Addressing mode whenever
f ≤ 95 (5Fh). See Section 22.2.3
“Byte-Oriented and Bit-Oriented
Instructions in Indexed Literal Offset
Mode” for details.
02h
01h
1
; result is positive
0
0
11da
Description:
Q Cycle Activity:
Decode
f {,d {,a}}
02h
03h
?
FFh ; (2’s complement)
0
; result is negative
0
1
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
SUBWF
REG, 1, 0
Example 1:
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
=
C
=
Z
=
N
=
Example 2:
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
=
C
=
Z
=
N
=
Example 3:
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
=
C
=
Z
=
N
=
© 2009 Microchip Technology Inc.
3
2
?
1
2
1
0
0
; result is positive
SUBWF
REG, 0, 0
2
2
?
2
0
1
1
0
SUBWF
; result is zero
REG, 1, 0
1
2
?
FFh ;(2’s complement)
2
0
; result is negative
0
1
DS39682E-page 285
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SUBWFB
Subtract W from f with Borrow
SWAPF
Swap f
Syntax:
SUBWFB
Syntax:
SWAPF f {,d {,a}}
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) – (W) – (C) → dest
Operation:
Status Affected:
N, OV, C, DC, Z
(f<3:0>) → dest<7:4>,
(f<7:4>) → dest<3:0>
Status Affected:
None
Encoding:
0101
Description:
f {,d {,a}}
10da
ffff
ffff
Subtract W and the Carry flag (borrow)
from register ‘f’ (2’s complement
method). If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Decode
Q2
Read
register ‘f’
Example 1:
SUBWFB
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
=
C
=
Z
=
N
=
Example 2:
Q4
Write to
destination
(0001 1001)
(0000 1101)
0Ch
0Dh
1
0
0
(0000 1011)
(0000 1101)
10da
ffff
ffff
The upper and lower nibbles of register
‘f’ are exchanged. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
placed in register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
REG, 1, 0
19h
0Dh
1
0011
Description:
Example:
SWAPF
Before Instruction
REG
=
After Instruction
REG
=
REG, 1, 0
53h
35h
; result is positive
SUBWFB REG, 0, 0
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
=
C
=
Z
=
N
=
Example 3:
1Bh
1Ah
0
(0001 1011)
(0001 1010)
1Bh
00h
1
1
0
(0001 1011)
SUBWFB
Before Instruction
REG
=
W
=
C
=
After Instruction
REG
=
W
C
Z
N
Q3
Process
Data
Encoding:
=
=
=
=
DS39682E-page 286
; result is zero
REG, 1, 0
03h
0Eh
1
(0000 0011)
(0000 1101)
F5h
(1111 0100)
; [2’s comp]
(0000 1101)
0Eh
0
0
1
; result is negative
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TBLRD
Table Read
TBLRD
Table Read (Continued)
Syntax:
TBLRD ( *; *+; *-; +*)
Example 1:
TBLRD
Operands:
None
Operation:
if TBLRD *,
(Prog Mem (TBLPTR)) → TABLAT,
TBLPTR – No Change;
if TBLRD *+,
(Prog Mem (TBLPTR)) → TABLAT,
(TBLPTR) + 1 → TBLPTR;
if TBLRD *-,
(Prog Mem (TBLPTR)) → TABLAT,
(TBLPTR) – 1 → TBLPTR;
if TBLRD +*,
(TBLPTR) + 1 → TBLPTR,
(Prog Mem (TBLPTR)) → TABLAT
Before Instruction
TABLAT
TBLPTR
MEMORY (00A356h)
After Instruction
TABLAT
TBLPTR
Example 2:
0000
0000
0000
TBLRD
=
=
=
55h
00A356h
34h
=
=
34h
00A357h
+* ;
Before Instruction
TABLAT
TBLPTR
MEMORY (01A357h)
MEMORY (01A358h)
After Instruction
TABLAT
TBLPTR
Status Affected: None
Encoding:
*+ ;
=
=
=
=
AAh
01A357h
12h
34h
=
=
34h
01A358h
10nn
nn=0 *
=1 *+
=2 *=3 +*
Description:
This instruction is used to read the contents
of Program Memory (P.M.). To address the
program memory, a pointer called Table
Pointer (TBLPTR) is used.
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory. TBLPTR
has a 2-Mbyte address range.
TBLPTR[0] = 0: Least Significant Byte
of Program Memory
Word
TBLPTR[0] = 1: Most Significant Byte
of Program Memory
Word
The TBLRD instruction can modify the value
of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words:
1
Cycles:
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
No
operation
No
operation
No
operation
No
operation
No operation
(Read Program
Memory)
No
operation
No operation
(Write TABLAT)
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TBLWT
Table Write
TBLWT
Table Write (Continued)
Syntax:
TBLWT ( *; *+; *-; +*)
Example 1:
TBLWT *+;
Operands:
None
Operation:
if TBLWT *,
(TABLAT) → Holding Register,
TBLPTR – No Change;
if TBLWT *+,
(TABLAT) → Holding Register,
(TBLPTR) + 1 → TBLPTR;
if TBLWT *-,
(TABLAT) → Holding Register,
(TBLPTR) – 1 → TBLPTR;
if TBLWT +*,
(TBLPTR) + 1 → TBLPTR,
(TABLAT) → Holding Register
Status Affected:
Before Instruction
TABLAT
=
55h
TBLPTR
=
00A356h
HOLDING REGISTER
(00A356h)
=
FFh
After Instructions (table write completion)
TABLAT
=
55h
TBLPTR
=
00A357h
HOLDING REGISTER
(00A356h)
=
55h
Example 2:
None
Encoding:
0000
0000
0000
11nn
nn=0 *
=1 *+
=2 *=3 +*
Description:
This instruction uses the 3 LSBs of
TBLPTR to determine which of the
8 holding registers the TABLAT is written
to. The holding registers are used to
program the contents of Program
Memory (P.M.). (Refer to Section 7.0
“Flash Program Memory” for additional
details on programming Flash memory.)
The TBLPTR (a 21-bit pointer) points to
each byte in the program memory.
TBLPTR has a 2-MByte address range.
The LSb of the TBLPTR selects which
byte of the program memory location to
access.
TBLPTR[0] = 0: Least Significant
Byte of Program
Memory Word
TBLPTR[0] = 1: Most Significant
Byte of Program
Memory Word
The TBLWT instruction can modify the
value of TBLPTR as follows:
• no change
• post-increment
• post-decrement
• pre-increment
Words:
1
Cycles:
2
TBLWT +*;
Before Instruction
TABLAT
=
34h
TBLPTR
=
01389Ah
HOLDING REGISTER
(01389Ah)
=
FFh
HOLDING REGISTER
(01389Bh)
=
FFh
After Instruction (table write completion)
TABLAT
=
34h
TBLPTR
=
01389Bh
HOLDING REGISTER
(01389Ah)
=
FFh
HOLDING REGISTER
(01389Bh)
=
34h
Q Cycle Activity:
Q1
Decode
Q2
Q3
Q4
No
No
No
operation operation operation
No
No
No
No
operation operation operation operation
(Write to
(Read
Holding
TABLAT)
Register )
DS39682E-page 288
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TSTFSZ
Test f, Skip if 0
XORLW
Exclusive OR Literal with W
Syntax:
TSTFSZ f {,a}
Syntax:
XORLW k
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
(W) .XOR. k → W
Status Affected:
N, Z
Operation:
skip if f = 0
Status Affected:
None
Encoding:
Encoding:
0110
Description:
011a
ffff
ffff
If ‘f’ = 0, the next instruction fetched
during the current instruction execution
is discarded and a NOP is executed,
making this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
0000
1010
kkkk
kkkk
Description:
The contents of W are XORed with
the 8-bit literal ‘k’. The result is placed
in W.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal ‘k’
Process
Data
Write to W
Example:
XORLW
0AFh
Before Instruction
W
=
After Instruction
W
=
B5h
1Ah
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
HERE
NZERO
ZERO
Before Instruction
PC
After Instruction
If CNT
PC
If CNT
PC
TSTFSZ
:
:
CNT, 1
=
Address (HERE)
=
=
≠
=
00h,
Address (ZERO)
00h,
Address (NZERO)
© 2009 Microchip Technology Inc.
DS39682E-page 289
PIC18F45J10 FAMILY
XORWF
Exclusive OR W with f
Syntax:
XORWF
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(W) .XOR. (f) → dest
Status Affected:
N, Z
Encoding:
0001
f {,d {,a}}
10da
ffff
ffff
Description:
Exclusive OR the contents of W with
register ‘f’. If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in the register ‘f’ (default).
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 22.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Example:
XORWF
Before Instruction
REG
=
W
=
After Instruction
REG
=
W
=
DS39682E-page 290
REG, 1, 0
AFh
B5h
1Ah
B5h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
22.2
A summary of the instructions in the extended instruction set is provided in Table 22-3. Detailed descriptions
are provided in Section 22.2.2 “Extended Instruction
Set”. The opcode field descriptions in Table 22-1
(page 250) apply to both the standard and extended
PIC18 instruction sets.
Extended Instruction Set
In addition to the standard 75 instructions of the PIC18
instruction set, PIC18F45J10 family devices also
provide an optional extension to the core CPU functionality. The added features include eight additional
instructions that augment indirect and indexed
addressing operations and the implementation of
Indexed Literal Offset Addressing mode for many of the
standard PIC18 instructions.
Note:
The additional features of the extended instruction set
are disabled by default. To enable them, users must set
the XINST Configuration bit.
The instructions in the extended set can all be
classified as literal operations, which either manipulate
the File Select Registers, or use them for indexed
addressing. Two of the instructions, ADDFSR and
SUBFSR, each have an additional special instantiation
for using FSR2. These versions (ADDULNK and
SUBULNK) allow for automatic return after execution.
22.2.1
EXTENDED INSTRUCTION SYNTAX
Most of the extended instructions use indexed arguments, using one of the File Select Registers and some
offset to specify a source or destination register. When
an argument for an instruction serves as part of
indexed addressing, it is enclosed in square brackets
(“[ ]”). This is done to indicate that the argument is used
as an index or offset. MPASM™ Assembler will flag an
error if it determines that an index or offset value is not
bracketed.
The extended instructions are specifically implemented
to optimize re-entrant program code (that is, code that
is recursive or that uses a software stack) written in
high-level languages, particularly C. Among other
things, they allow users working in high-level
languages to perform certain operations on data
structures more efficiently. These include:
When the extended instruction set is enabled, brackets
are also used to indicate index arguments in byteoriented and bit-oriented instructions. This is in addition
to other changes in their syntax. For more details, see
Section 22.2.3.1 “Extended Instruction Syntax with
Standard PIC18 Commands”.
• dynamic allocation and deallocation of software
stack space when entering and leaving
subroutines
• Function Pointer invocation
• Software Stack Pointer manipulation
• manipulation of variables located in a software
stack
TABLE 22-3:
The instruction set extension and the
Indexed Literal Offset Addressing mode
were designed for optimizing applications
written in C; the user may likely never use
these instructions directly in assembler.
The syntax for these commands is provided as a reference for users who may be
reviewing code that has been generated
by a compiler.
Note:
In the past, square brackets have been
used to denote optional arguments in the
PIC18 and earlier instruction sets. In this
text and going forward, optional
arguments are denoted by braces (“{ }”).
EXTENSIONS TO THE PIC18 INSTRUCTION SET
16-Bit Instruction Word
Mnemonic,
Operands
ADDFSR
ADDULNK
CALLW
MOVSF
f, k
k
MOVSS
zs, zd
PUSHL
k
SUBFSR
SUBULNK
f, k
k
zs, fd
Description
Cycles
MSb
Add Literal to FSR
Add Literal to FSR2 and Return
Call Subroutine using WREG
Move zs (source) to 1st Word
2nd Word
fd (destination)
Move zs (source) to 1st Word
2nd Word
zd (destination)
Store Literal at FSR2,
Decrement FSR2
Subtract Literal from FSR
Subtract Literal from FSR2 and
Return
© 2009 Microchip Technology Inc.
1
2
2
2
LSb
Status
Affected
1000
1000
0000
1011
ffff
1011
xxxx
1010
ffkk
11kk
0001
0zzz
ffff
1zzz
xzzz
kkkk
kkkk
kkkk
0100
zzzz
ffff
zzzz
zzzz
kkkk
None
None
None
None
1
1110
1110
0000
1110
1111
1110
1111
1110
1
2
1110
1110
1001
1001
ffkk
11kk
kkkk
kkkk
None
None
2
None
None
DS39682E-page 291
PIC18F45J10 FAMILY
22.2.2
EXTENDED INSTRUCTION SET
ADDFSR
Add Literal to FSR
ADDULNK
Syntax:
ADDFSR f, k
Syntax:
ADDULNK k
Operands:
0 ≤ k ≤ 63
f ∈ [ 0, 1, 2 ]
Operands:
0 ≤ k ≤ 63
Operation:
FSR(f) + k → FSR(f)
Status Affected:
None
Encoding:
1110
Add Literal to FSR2 and Return
FSR2 + k → FSR2,
Operation:
(TOS) → PC
Status Affected:
1000
ffkk
kkkk
Description:
The 6-bit literal ‘k’ is added to the
contents of the FSR specified by ‘f’.
Words:
1
Cycles:
1
None
Encoding:
1110
Q1
Q2
Q3
Q4
Read
literal ‘k’
Process
Data
Write to
FSR
Example:
ADDFSR 2, 23h
Before Instruction
FSR2
=
03FFh
After Instruction
FSR2
=
0422h
kkkk
Words:
1
Cycles:
2
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal ‘k’
Process
Data
Write to
FSR
No
Operation
No
Operation
No
Operation
No
Operation
Example:
Note:
11kk
The 6-bit literal ‘k’ is added to the
contents of FSR2. A RETURN is then
executed by loading the PC with the
TOS.
The instruction takes two cycles to
execute; a NOP is performed during
the second cycle.
This may be thought of as a special
case of the ADDFSR instruction,
where f = 3 (binary ‘11’); it operates
only on FSR2.
Q Cycle Activity:
Decode
1000
Description:
ADDULNK 23h
Before Instruction
FSR2
=
PC
=
03FFh
0100h
After Instruction
FSR2
=
PC
=
0422h
(TOS)
All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in
symbolic addressing. If a label is used, the instruction syntax then becomes: {label} instruction argument(s).
DS39682E-page 292
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
CALLW
Subroutine Call Using WREG
MOVSF
Syntax:
CALLW
Syntax:
MOVSF [zs], fd
Operands:
None
Operands:
Operation:
(PC + 2) → TOS,
(W) → PCL,
(PCLATH) → PCH,
(PCLATU) → PCU
0 ≤ zs ≤ 127
0 ≤ fd ≤ 4095
Operation:
((FSR2) + zs) → fd
Status Affected:
None
Status Affected:
None
Encoding:
0000
0000
0001
0100
Description
First, the return address (PC + 2) is
pushed onto the return stack. Next, the
contents of W are written to PCL; the
existing value is discarded. Then, the
contents of PCLATH and PCLATU are
latched into PCH and PCU,
respectively. The second cycle is
executed as a NOP instruction while the
new next instruction is fetched.
Unlike CALL, there is no option to
update W, STATUS or BSR.
Words:
1
Cycles:
2
Move Indexed to f
Encoding:
1st word (source)
2nd word (destin.)
Q1
Q2
Q3
Q4
Read
WREG
PUSH PC to
stack
No
operation
No
operation
No
operation
No
operation
No
operation
HERE
Before Instruction
PC
=
PCLATH =
PCLATU =
W
=
After Instruction
PC
=
TOS
=
PCLATH =
PCLATU =
W
=
2
Cycles:
2
Q Cycle Activity:
Q1
Decode
address (HERE)
10h
00h
06h
© 2009 Microchip Technology Inc.
zzzzs
ffffd
Words:
CALLW
001006h
address (HERE + 2)
10h
00h
06h
0zzz
ffff
The contents of the source register are
moved to destination register ‘fd’. The
actual address of the source register is
determined by adding the 7-bit literal
offset ‘zs’ in the first word to the value of
FSR2. The address of the destination
register is specified by the 12-bit literal
‘fd’ in the second word. Both addresses
can be anywhere in the 4096-byte data
space (000h to FFFh).
The MOVSF instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register.
If the resultant source address points to
an indirect addressing register, the
value returned will be 00h.
Decode
Example:
1011
ffff
Description:
Q Cycle Activity:
Decode
1110
1111
Q2
Q3
Determine
Determine
source addr source addr
No
operation
No
operation
No dummy
read
Example:
MOVSF
Before Instruction
FSR2
Contents
of 85h
REG2
After Instruction
FSR2
Contents
of 85h
REG2
Q4
Read
source reg
Write
register ‘f’
(dest)
[05h], REG2
=
80h
=
=
33h
11h
=
80h
=
=
33h
33h
DS39682E-page 293
PIC18F45J10 FAMILY
MOVSS
Move Indexed to Indexed
PUSHL
Syntax:
Syntax:
PUSHL k
Operands:
MOVSS [zs], [zd]
0 ≤ zs ≤ 127
0 ≤ zd ≤ 127
Operands:
0 ≤ k ≤ 255
Operation:
((FSR2) + zs) → ((FSR2) + zd)
Operation:
k → (FSR2),
FSR2 – 1 → FSR2
Status Affected:
None
Status Affected:
None
Encoding:
1st word (source)
2nd word (dest.)
1110
1111
Description
1011
xxxx
1zzz
xzzz
zzzzs
zzzzd
The contents of the source register are
moved to the destination register. The
addresses of the source and destination
registers are determined by adding the
7-bit literal offsets ‘zs’ or ‘zd’,
respectively, to the value of FSR2. Both
registers can be located anywhere in
the 4096-byte data memory space
(000h to FFFh).
The MOVSS instruction cannot use the
PCL, TOSU, TOSH or TOSL as the
destination register.
If the resultant source address points to
an indirect addressing register, the
value returned will be 00h. If the
resultant destination address points to
an indirect addressing register, the
instruction will execute as a NOP.
Words:
2
Cycles:
2
Q Cycle Activity:
Q1
Decode
Decode
Q2
Q3
Determine
Determine
source addr source addr
Determine
dest addr
Example:
Encoding:
1111
1010
kkkk
kkkk
Description:
The 8-bit literal ‘k’ is written to the data
memory address specified by FSR2. FSR2
is decremented by 1 after the operation.
This instruction allows users to push values
onto a software stack.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read ‘k’
Process
data
Write to
destination
Example:
PUSHL 08h
Before Instruction
FSR2H:FSR2L
Memory (01ECh)
=
=
01ECh
00h
After Instruction
FSR2H:FSR2L
Memory (01ECh)
=
=
01EBh
08h
Q4
Read
source reg
Write
to dest reg
MOVSS [05h], [06h]
Before Instruction
FSR2
Contents
of 85h
Contents
of 86h
After Instruction
FSR2
Contents
of 85h
Contents
of 86h
DS39682E-page 294
Determine
dest addr
Store Literal at FSR2, Decrement FSR2
=
80h
=
33h
=
11h
=
80h
=
33h
=
33h
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
SUBFSR
Subtract Literal from FSR
SUBULNK
Syntax:
SUBFSR f, k
Syntax:
SUBULNK k
Operands:
0 ≤ k ≤ 63
Operands:
0 ≤ k ≤ 63
f ∈ [ 0, 1, 2 ]
Operation:
Operation:
FSR(f) – k → FSRf
Status Affected:
None
Encoding:
1110
FSR2 – k → FSR2
(TOS) → PC
Status Affected: None
1001
ffkk
kkkk
Description:
The 6-bit literal ‘k’ is subtracted from
the contents of the FSR specified by
‘f’.
Words:
1
Cycles:
1
Encoding:
1110
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
SUBFSR 2, 23h
1001
11kk
kkkk
Description:
The 6-bit literal ‘k’ is subtracted from the
contents of the FSR2. A RETURN is then
executed by loading the PC with the TOS.
The instruction takes two cycles to
execute; a NOP is performed during the
second cycle.
This may be thought of as a special case of
the SUBFSR instruction, where f = 3 (binary
‘11’); it operates only on FSR2.
Words:
1
Cycles:
2
Q Cycle Activity:
Example:
Subtract Literal from FSR2 and Return
Q Cycle Activity:
Before Instruction
FSR2
=
Q1
Q2
Q3
Q4
03FFh
Decode
After Instruction
FSR2
=
Read
register ‘f’
Process
Data
Write to
destination
03DCh
No
Operation
No
Operation
No
Operation
No
Operation
Example:
© 2009 Microchip Technology Inc.
SUBULNK 23h
Before Instruction
FSR2
=
PC
=
03FFh
0100h
After Instruction
FSR2
=
PC
=
03DCh
(TOS)
DS39682E-page 295
PIC18F45J10 FAMILY
22.2.3
Note:
BYTE-ORIENTED AND
BIT-ORIENTED INSTRUCTIONS IN
INDEXED LITERAL OFFSET MODE
Enabling the PIC18 instruction set
extension may cause legacy applications
to behave erratically or fail entirely.
In addition to eight new commands in the extended set,
enabling the extended instruction set also enables
Indexed Literal Offset Addressing mode (Section 6.5.1
“Indexed Addressing with Literal Offset”). This has
a significant impact on the way that many commands of
the standard PIC18 instruction set are interpreted.
When the extended set is disabled, addresses embedded in opcodes are treated as literal memory locations:
either as a location in the Access Bank (‘a’ = 0), or in a
GPR bank designated by the BSR (‘a’ = 1). When the
extended instruction set is enabled and ‘a’ = 0, however, a file register argument of 5Fh or less is
interpreted as an offset from the pointer value in FSR2
and not as a literal address. For practical purposes, this
means that all instructions that use the Access RAM bit
as an argument – that is, all byte-oriented and bitoriented instructions, or almost half of the core PIC18
instructions – may behave differently when the
extended instruction set is enabled.
When the content of FSR2 is 00h, the boundaries of the
Access RAM are essentially remapped to their original
values. This may be useful in creating backward
compatible code. If this technique is used, it may be
necessary to save the value of FSR2 and restore it
when moving back and forth between C and assembly
routines in order to preserve the Stack Pointer. Users
must also keep in mind the syntax requirements of the
extended instruction set (see Section 22.2.3.1
“Extended Instruction Syntax with Standard PIC18
Commands”).
Although the Indexed Literal Offset Addressing mode
can be very useful for dynamic stack and pointer
manipulation, it can also be very annoying if a simple
arithmetic operation is carried out on the wrong
register. Users who are accustomed to the PIC18 programming must keep in mind that, when the extended
instruction set is enabled, register addresses of 5Fh or
less are used for Indexed Literal Offset Addressing.
Representative examples of typical byte-oriented and
bit-oriented instructions in the Indexed Literal Offset
Addressing mode are provided on the following page to
show how execution is affected. The operand conditions shown in the examples are applicable to all
instructions of these types.
DS39682E-page 296
22.2.3.1
Extended Instruction Syntax with
Standard PIC18 Commands
When the extended instruction set is enabled, the file
register argument, ‘f’, in the standard byte-oriented and
bit-oriented commands is replaced with the literal offset
value, ‘k’. As already noted, this occurs only when ‘f’ is
less than or equal to 5Fh. When an offset value is used,
it must be indicated by square brackets (“[ ]”). As with
the extended instructions, the use of brackets indicates
to the compiler that the value is to be interpreted as an
index or an offset. Omitting the brackets, or using a
value greater than 5Fh within brackets, will generate an
error in the MPASM Assembler.
If the index argument is properly bracketed for Indexed
Literal Offset Addressing, the Access RAM argument is
never specified; it will automatically be assumed to be
‘0’. This is in contrast to standard operation (extended
instruction set disabled) when ‘a’ is set on the basis of
the target address. Declaring the Access RAM bit in
this mode will also generate an error in the MPASM
Assembler.
The destination argument, ‘d’, functions as before.
Refer to the MPLAB® IDE, MPASM™ or MPLAB C18
documentation for information on enabling Extended
Instruction set support
22.2.4
CONSIDERATIONS WHEN
ENABLING THE EXTENDED
INSTRUCTION SET
It is important to note that the extensions to the instruction set may not be beneficial to all users. In particular,
users who are not writing code that uses a software
stack may not benefit from using the extensions to the
instruction set.
Additionally, the Indexed Literal Offset Addressing
mode may create issues with legacy applications
written to the PIC18 assembler. This is because
instructions in the legacy code may attempt to address
registers in the Access Bank below 5Fh. Since these
addresses are interpreted as literal offsets to FSR2
when the instruction set extension is enabled, the
application may read or write to the wrong data
addresses.
When porting an application to the PIC18F45J10
family, it is very important to consider the type of code.
A large, re-entrant application that is written in ‘C’ and
would benefit from efficient compilation will do well
when using the instruction set extensions. Legacy
applications that heavily use the Access Bank will most
likely not benefit from using the extended instruction
set.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
ADDWF
ADD W to Indexed
(Indexed Literal Offset mode)
BSF
Bit Set Indexed
(Indexed Literal Offset mode)
Syntax:
ADDWF
Syntax:
BSF [k], b
Operands:
0 ≤ k ≤ 95
d ∈ [0,1]
Operands:
0 ≤ f ≤ 95
0≤b≤7
Operation:
(W) + ((FSR2) + k) → dest
Operation:
1 → ((FSR2) + k)<b>
Status Affected:
N, OV, C, DC, Z
Status Affected:
None
Encoding:
[k] {,d}
0010
Description:
01d0
kkkk
kkkk
The contents of W are added to the
contents of the register indicated by
FSR2, offset by the value ‘k’.
If ‘d’ is ‘0’, the result is stored in W. If ‘d’
is ‘1’, the result is stored back in
register ‘f’ (default).
Encoding:
1000
bbb0
kkkk
kkkk
Description:
Bit ‘b’ of the register indicated by FSR2,
offset by the value ‘k’, is set.
Words:
1
Cycles:
1
Q Cycle Activity:
Words:
1
Q1
Q2
Q3
Q4
Cycles:
1
Decode
Read
register ‘f’
Process
Data
Write to
destination
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read ‘k’
Process
Data
Write to
destination
Example:
ADDWF
[OFST] , 0
Before Instruction
W
OFST
FSR2
Contents
of 0A2Ch
After Instruction
W
Contents
of 0A2Ch
=
=
=
17h
2Ch
0A00h
=
20h
=
37h
=
20h
Example:
BSF
Before Instruction
FLAG_OFST
FSR2
Contents
of 0A0Ah
After Instruction
Contents
of 0A0Ah
[FLAG_OFST], 7
=
=
0Ah
0A00h
=
55h
=
D5h
SETF
Set Indexed
(Indexed Literal Offset mode)
Syntax:
SETF [k]
Operands:
0 ≤ k ≤ 95
Operation:
FFh → ((FSR2) + k)
Status Affected:
None
Encoding:
0110
1000
kkkk
kkkk
Description:
The contents of the register indicated by
FSR2, offset by ‘k’, are set to FFh.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read ‘k’
Process
Data
Write
register
Example:
SETF
Before Instruction
OFST
FSR2
Contents
of 0A2Ch
After Instruction
Contents
of 0A2Ch
© 2009 Microchip Technology Inc.
[OFST]
=
=
2Ch
0A00h
=
00h
=
FFh
DS39682E-page 297
PIC18F45J10 FAMILY
22.2.5
SPECIAL CONSIDERATIONS WITH
MICROCHIP MPLAB® IDE TOOLS
The latest versions of Microchip’s software tools have
been designed to fully support the extended instruction
set of the PIC18F45J10 family of devices. This includes
the MPLAB C18 C compiler, MPASM assembly language and MPLAB Integrated Development
Environment (IDE).
When selecting a target device for software
development, MPLAB IDE will automatically set default
Configuration bits for that device. The default setting for
the XINST Configuration bit is ‘0’, disabling the
extended instruction set and Indexed Literal Offset
Addressing mode. For proper execution of applications
developed to take advantage of the extended
instruction set, XINST must be set during
programming.
DS39682E-page 298
To develop software for the extended instruction set,
the user must enable support for the instructions and
the Indexed Addressing mode in their language tool(s).
Depending on the environment being used, this may be
done in several ways:
• A menu option, or dialog box within the
environment, that allows the user to configure the
language tool and its settings for the project
• A command line option
• A directive in the source code
These options vary between different compilers,
assemblers and development environments. Users are
encouraged to review the documentation accompanying their development systems for the appropriate
information.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
23.0
DEVELOPMENT SUPPORT
The PIC® microcontrollers are supported with a full
range of hardware and software development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Assemblers/Compilers/Linkers
- MPASMTM Assembler
- MPLAB C18 and MPLAB C30 C Compilers
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
- MPLAB ASM30 Assembler/Linker/Library
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB ICE 2000 In-Circuit Emulator
- MPLAB REAL ICE™ In-Circuit Emulator
• In-Circuit Debugger
- MPLAB ICD 2
• Device Programmers
- PICSTART® Plus Development Programmer
- MPLAB PM3 Device Programmer
- PICkit™ 2 Development Programmer
• Low-Cost Demonstration and Development
Boards and Evaluation Kits
23.1
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8/16-bit microcontroller market. The MPLAB IDE is a Windows®
operating system-based application that contains:
• A single graphical interface to all debugging tools
- Simulator
- Programmer (sold separately)
- Emulator (sold separately)
- In-Circuit Debugger (sold separately)
• A full-featured editor with color-coded context
• A multiple project manager
• Customizable data windows with direct edit of
contents
• High-level source code debugging
• Visual device initializer for easy register
initialization
• Mouse over variable inspection
• Drag and drop variables from source to watch
windows
• Extensive on-line help
• Integration of select third party tools, such as
HI-TECH Software C Compilers and IAR
C Compilers
The MPLAB IDE allows you to:
• Edit your source files (either assembly or C)
• One touch assemble (or compile) and download
to PIC MCU emulator and simulator tools
(automatically updates all project information)
• Debug using:
- Source files (assembly or C)
- Mixed assembly and C
- Machine code
MPLAB IDE supports multiple debugging tools in a
single development paradigm, from the cost-effective
simulators, through low-cost in-circuit debuggers, to
full-featured emulators. This eliminates the learning
curve when upgrading to tools with increased flexibility
and power.
© 2009 Microchip Technology Inc.
DS39682E-page 299
PIC18F45J10 FAMILY
23.2
MPASM Assembler
The MPASM Assembler is a full-featured, universal
macro assembler for all PIC MCUs.
The MPASM Assembler generates relocatable object
files for the MPLINK Object Linker, Intel® standard HEX
files, MAP files to detail memory usage and symbol
reference, absolute LST files that contain source lines
and generated machine code and COFF files for
debugging.
The MPASM Assembler features include:
• Integration into MPLAB IDE projects
• User-defined macros to streamline
assembly code
• Conditional assembly for multi-purpose
source files
• Directives that allow complete control over the
assembly process
23.5
MPLAB ASM30 Assembler produces relocatable
machine code from symbolic assembly language for
dsPIC30F devices. MPLAB C30 C Compiler uses the
assembler to produce its object file. The assembler
generates relocatable object files that can then be
archived or linked with other relocatable object files and
archives to create an executable file. Notable features
of the assembler include:
•
•
•
•
•
•
Support for the entire dsPIC30F instruction set
Support for fixed-point and floating-point data
Command line interface
Rich directive set
Flexible macro language
MPLAB IDE compatibility
23.6
23.3
MPLAB C18 and MPLAB C30
C Compilers
The MPLAB C18 and MPLAB C30 Code Development
Systems are complete ANSI C compilers for
Microchip’s PIC18 and PIC24 families of microcontrollers and the dsPIC30 and dsPIC33 family of digital
signal controllers. These compilers provide powerful
integration capabilities, superior code optimization and
ease of use not found with other compilers.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
23.4
MPLINK Object Linker/
MPLIB Object Librarian
The MPLINK Object Linker combines relocatable
objects created by the MPASM Assembler and the
MPLAB C18 C Compiler. It can link relocatable objects
from precompiled libraries, using directives from a
linker script.
MPLAB ASM30 Assembler, Linker
and Librarian
MPLAB SIM Software Simulator
The MPLAB SIM Software Simulator allows code
development in a PC-hosted environment by simulating the PIC MCUs and dsPIC® DSCs on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a comprehensive stimulus controller. Registers can be
logged to files for further run-time analysis. The trace
buffer and logic analyzer display extend the power of
the simulator to record and track program execution,
actions on I/O, most peripherals and internal registers.
The MPLAB SIM Software Simulator fully supports
symbolic debugging using the MPLAB C18 and
MPLAB C30 C Compilers, and the MPASM and
MPLAB ASM30 Assemblers. The software simulator
offers the flexibility to develop and debug code outside
of the hardware laboratory environment, making it an
excellent, economical software development tool.
The MPLIB Object Librarian manages the creation and
modification of library files of precompiled code. When
a routine from a library is called from a source file, only
the modules that contain that routine will be linked in
with the application. This allows large libraries to be
used efficiently in many different applications.
The object linker/library features include:
• Efficient linking of single libraries instead of many
smaller files
• Enhanced code maintainability by grouping
related modules together
• Flexible creation of libraries with easy module
listing, replacement, deletion and extraction
DS39682E-page 300
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
23.7
MPLAB ICE 2000
High-Performance
In-Circuit Emulator
The MPLAB ICE 2000 In-Circuit Emulator is intended
to provide the product development engineer with a
complete microcontroller design tool set for PIC
microcontrollers. Software control of the MPLAB ICE
2000 In-Circuit Emulator is advanced by the MPLAB
Integrated Development Environment, which allows
editing, building, downloading and source debugging
from a single environment.
The MPLAB ICE 2000 is a full-featured emulator
system with enhanced trace, trigger and data monitoring features. Interchangeable processor modules allow
the system to be easily reconfigured for emulation of
different processors. The architecture of the MPLAB
ICE 2000 In-Circuit Emulator allows expansion to
support new PIC microcontrollers.
The MPLAB ICE 2000 In-Circuit Emulator system has
been designed as a real-time emulation system with
advanced features that are typically found on more
expensive development tools. The PC platform and
Microsoft® Windows® 32-bit operating system were
chosen to best make these features available in a
simple, unified application.
23.8
MPLAB REAL ICE In-Circuit
Emulator System
MPLAB REAL ICE In-Circuit Emulator System is
Microchip’s next generation high-speed emulator for
Microchip Flash DSC and MCU devices. It debugs and
programs PIC® Flash MCUs and dsPIC® Flash DSCs
with the easy-to-use, powerful graphical user interface of
the MPLAB Integrated Development Environment (IDE),
included with each kit.
The MPLAB REAL ICE probe is connected to the design
engineer’s PC using a high-speed USB 2.0 interface and
is connected to the target with either a connector
compatible with the popular MPLAB ICD 2 system
(RJ11) or with the new high-speed, noise tolerant, LowVoltage Differential Signal (LVDS) interconnection
(CAT5).
23.9
MPLAB ICD 2 In-Circuit Debugger
Microchip’s In-Circuit Debugger, MPLAB ICD 2, is a
powerful, low-cost, run-time development tool,
connecting to the host PC via an RS-232 or high-speed
USB interface. This tool is based on the Flash PIC
MCUs and can be used to develop for these and other
PIC MCUs and dsPIC DSCs. The MPLAB ICD 2 utilizes
the in-circuit debugging capability built into the Flash
devices. This feature, along with Microchip’s In-Circuit
Serial ProgrammingTM (ICSPTM) protocol, offers costeffective, in-circuit Flash debugging from the graphical
user interface of the MPLAB Integrated Development
Environment. This enables a designer to develop and
debug source code by setting breakpoints, single stepping and watching variables, and CPU status and
peripheral registers. Running at full speed enables
testing hardware and applications in real time. MPLAB
ICD 2 also serves as a development programmer for
selected PIC devices.
23.10 MPLAB PM3 Device Programmer
The MPLAB PM3 Device Programmer is a universal,
CE compliant device programmer with programmable
voltage verification at VDDMIN and VDDMAX for
maximum reliability. It features a large LCD display
(128 x 64) for menus and error messages and a modular, detachable socket assembly to support various
package types. The ICSP™ cable assembly is included
as a standard item. In Stand-Alone mode, the MPLAB
PM3 Device Programmer can read, verify and program
PIC devices without a PC connection. It can also set
code protection in this mode. The MPLAB PM3
connects to the host PC via an RS-232 or USB cable.
The MPLAB PM3 has high-speed communications and
optimized algorithms for quick programming of large
memory devices and incorporates an SD/MMC card for
file storage and secure data applications.
MPLAB REAL ICE is field upgradeable through future
firmware downloads in MPLAB IDE. In upcoming
releases of MPLAB IDE, new devices will be supported,
and new features will be added, such as software breakpoints and assembly code trace. MPLAB REAL ICE
offers significant advantages over competitive emulators
including low-cost, full-speed emulation, real-time
variable watches, trace analysis, complex breakpoints, a
ruggedized probe interface and long (up to three meters)
interconnection cables.
© 2009 Microchip Technology Inc.
DS39682E-page 301
PIC18F45J10 FAMILY
23.11 PICSTART Plus Development
Programmer
23.13 Demonstration, Development and
Evaluation Boards
The PICSTART Plus Development Programmer is an
easy-to-use, low-cost, prototype programmer. It
connects to the PC via a COM (RS-232) port. MPLAB
Integrated Development Environment software makes
using the programmer simple and efficient. The
PICSTART Plus Development Programmer supports
most PIC devices in DIP packages up to 40 pins.
Larger pin count devices, such as the PIC16C92X and
PIC17C76X, may be supported with an adapter socket.
The PICSTART Plus Development Programmer is CE
compliant.
A wide variety of demonstration, development and
evaluation boards for various PIC MCUs and dsPIC
DSCs allows quick application development on fully functional systems. Most boards include prototyping areas for
adding custom circuitry and provide application firmware
and source code for examination and modification.
23.12 PICkit 2 Development Programmer
The PICkit™ 2 Development Programmer is a low-cost
programmer and selected Flash device debugger with
an easy-to-use interface for programming many of
Microchip’s baseline, mid-range and PIC18F families of
Flash memory microcontrollers. The PICkit 2 Starter Kit
includes a prototyping development board, twelve
sequential lessons, software and HI-TECH’s PICC™
Lite C compiler, and is designed to help get up to speed
quickly using PIC® microcontrollers. The kit provides
everything needed to program, evaluate and develop
applications using Microchip’s powerful, mid-range
Flash memory family of microcontrollers.
DS39682E-page 302
The boards support a variety of features, including LEDs,
temperature sensors, switches, speakers, RS-232
interfaces, LCD displays, potentiometers and additional
EEPROM memory.
The demonstration and development boards can be
used in teaching environments, for prototyping custom
circuits and for learning about various microcontroller
applications.
In addition to the PICDEM™ and dsPICDEM™ demonstration/development board series of circuits, Microchip
has a line of evaluation kits and demonstration software
for analog filter design, KEELOQ® security ICs, CAN,
IrDA®, PowerSmart battery management, SEEVAL®
evaluation system, Sigma-Delta ADC, flow rate
sensing, plus many more.
Check the Microchip web page (www.microchip.com)
for the complete list of demonstration, development
and evaluation kits.
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings(†)
Ambient temperature under bias.............................................................................................................-40°C to +100°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any digital-only input MCLR I/O pin with respect to VSS ........................................................... -0.3V to 6.0V
Voltage on any combined digital and analog pin with respect to VSS ............................................ -0.3V to (VDD + 0.3V)
Voltage on VDDCORE with respect to VSS ................................................................................................... -0.3V to 2.75V
Voltage on VDD with respect to VSS ........................................................................................................... -0.3V to 4.0V
Total power dissipation (Note 1) ...............................................................................................................................1.0W
Maximum current out of VSS pin ...........................................................................................................................300 mA
Maximum current into VDD pin ..............................................................................................................................250 mA
Maximum output current sunk by any PORTB and PORTC I/O pin........................................................................25 mA
Maximum output current sunk by any PORTA, PORTD, and PORTE I/O pin...........................................................4 mA
Maximum output current sourced by any PORTB and PORTC I/O pin ..................................................................25 mA
Maximum output current sourced by any PORTA, PORTD, and PORTE I/O pin .....................................................4 mA
Maximum current sunk by all ports combined.......................................................................................................200 mA
Maximum current sourced by all ports combined..................................................................................................200 mA
Note 1: Power dissipation is calculated as follows:
Pdis = VDD x {IDD – ∑ IOH} + ∑ {(VDD – VOH) x IOH} + ∑(VOL x IOL)
† NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. This is a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for
extended periods may affect device reliability.
© 2009 Microchip Technology Inc.
DS39682E-page 303
PIC18F45J10 FAMILY
FIGURE 24-1:
PIC18LF45J10 FAMILY VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL)
3.00V
Voltage (VDDCORE)(1)
2.75V
2.7V
2.50V
PIC18LF24J10/25J10/44J10/45J10
2.35V
2.25V
2.00V
40 MHz
4 MHz
Frequency
For VDDCORE values, 2V to 2.35V, FMAX = (102.85 MHz/V) * (VDDCORE – 2V) + 4 MHz
Note 1:
FIGURE 24-2:
For devices without the voltage regulator, VDD and VDDCORE must be maintained so
that VDDCORE ≤ VDD ≤ 3.6V.
PIC18F45J10 FAMILY VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL)
4.0V
3.6V
Voltage (VDD)
3.5V
PIC18F2XJ10/4XJ10
3.0V
2.7V
2.5V
40 MHz
4 MHz
Frequency
DS39682E-page 304
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
D005
24.1
DC Characteristics:
Supply Voltage
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial)
PIC18F45J10 Family
(Industrial)
Param
No.
D001
Symbol
VDD
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Characteristic
Supply Voltage
Min
Typ
VDDCORE
—
3.6
V
PIC18LF4XJ10, PIC18LF2XJ10
(1)
Max Units
Conditions
D001
VDD
—
3.6
V
PIC18F4X/2XJ10
D001B
VDDCORE External Supply for
Microcontroller Core
2.0
—
2.7
V
Valid only in parts designated “LF”.
See Section 21.3 “On-Chip
Voltage Regulator” for details.
D002
VDR
RAM Data Retention
Voltage(1)
1.5
—
—
V
D003
VPOR
VDD Start Voltage
to ensure internal
Power-on Reset signal
—
—
0.15
V
D004
SVDD
VDD Rise Rate
to ensure internal
Power-on Reset signal
0.05
—
—
D005
VBOR
Brown-out Reset (BOR)
Voltage
2.35
2.5
2.7
Note 1:
This is the limit to which VDD can be lowered in Sleep mode, or during a device Reset, without losing RAM
data.
Supply Voltage
© 2009 Microchip Technology Inc.
2.7
SeeSection 5.3 “Power-on
Reset (POR)” for details
V/ms See Section 5.3 “Power-on
Reset (POR)” for details
V
DS39682E-page 305
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
Conditions
Power-Down Current (IPD)(1)
All devices
All devices
Note 1:
2:
3:
19
104
μA
-40°C
25
104
μA
+25°C
40
184
μA
+85°C
20
203
μA
-40°C
25
203
μA
+25°C
45
289
μA
+85°C
VDD = 2.5V
(Sleep mode)
VDD = 3.3V
(Sleep mode)
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
DS39682E-page 306
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
Conditions
3.8
7.7
mA
-40°C
3.7
7.5
mA
+25°C
3.7
7.5
mA
+85°C
3.9
7.9
mA
-40°C
Supply Current (IDD)(2)
All devices
All devices
All devices
All devices
Note 1:
2:
3:
3.7
7.5
mA
+25°C
3.7
7.5
mA
+85°C
64
167
μA
-40°C
77
193
μA
+25°C
95
269
μA
+85°C
65
266
μA
-40°C
79
294
μA
+25°C
98
360
μA
+85°C
VDD = 2.5V
FOSC = 31 kHz
(RC_RUN mode,
Internal oscillator source)
VDD = 3.3V
VDD = 2.5V
FOSC = 31 kHz
(RC_IDLE mode,
Internal oscillator source)
VDD = 3.3V
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
© 2009 Microchip Technology Inc.
DS39682E-page 307
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
4.2
8.5
mA
Conditions
Supply Current (IDD)(2)
All devices
All devices
All devices
All devices
All devices
All devices
Note 1:
2:
3:
-40°C
3.9
8.0
mA
+25°C
3.6
7.3
mA
+85°C
4.3
8.6
mA
-40°C
4.0
8.1
mA
+25°C
+85°C
3.7
7.6
mA
4.6
9.3
mA
-40°C
4.3
8.7
mA
+25°C
4.0
8.1
mA
+85°C
4.7
9.4
mA
-40°C
4.4
8.8
mA
+25°C
4.1
8.2
mA
+85°C
11.0
22.0
mA
-40°C
10.5
21.0
mA
+25°C
10.0
20.0
mA
+85°C
12.0
24.0
mA
-40°C
11.5
23.0
mA
+25°C
11.0
22.0
mA
+85°C
VDD = 2.5V
FOSC = 1 MHz
(PRI_RUN mode,
EC oscillator)
VDD = 3.3V
VDD = 2.5V
FOSC = 4 MHz
(PRI_RUN mode,
EC oscillator)
VDD = 3.3V
VDD = 2.5V
FOSC = 40 MHz
(PRI_RUN mode,
EC oscillator)
VDD = 3.3V
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
DS39682E-page 308
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
Conditions
Supply Current (IDD)(2)
All devices
All devices
All devices
All devices
Note 1:
2:
3:
6.2
14
mA
-40°C
5.7
13
mA
+25°C
5.7
13
mA
+85°C
6.6
15
mA
-40°C
6.1
14
mA
+25°C
+85°C
6.1
14
mA
11.0
22
mA
-40°C
10.5
21
mA
+25°C
10.0
20
mA
+85°C
12.0
24
mA
-40°C
11.5
23
mA
+25°C
11.0
22
mA
+85°C
VDD = 2.5V
FOSC = 4 MHZ,
16 MHZ internal
(PRI_RUN HS+PLL)
VDD = 3.3V
FOSC = 4 MHZ,
16 MHZ internal
(PRI_RUN HS+PLL)
VDD = 2.5V
FOSC = 10 MHZ,
40 MHZ internal
(PRI_RUN HS+PLL)
VDD = 3.3V
FOSC = 10 MHZ,
40 MHZ internal
(PRI_RUN HS+PLL)
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
© 2009 Microchip Technology Inc.
DS39682E-page 309
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
Conditions
Supply Current (IDD)(2)
All devices
All devices
All devices
All devices
All devices
All devices
Note 1:
2:
3:
150
337
μA
-40°C
160
355
μA
+25°C
220
512
μA
+85°C
190
518
μA
-40°C
200
528
μA
+25°C
250
647
μA
+85°C
350
737
μA
-40°C
375
787
μA
+25°C
420
917
μA
+85°C
410
954
μA
-40°C
0.450
1.03
mA
+25°C
0.475
1.13
mA
+85°C
5.0
10.1
mA
-40°C
5.2
10.6
mA
+25°C
5.5
11.1
mA
+85°C
5.5
11.1
mA
-40°C
6.0
12.1
mA
+25°C
6.5
13.1
mA
+85°C
VDD = 2.5V
FOSC = 1 MHz
(PRI_IDLE mode,
EC oscillator)
VDD = 3.3V
VDD = 2.5V
FOSC = 4 MHz
(PRI_IDLE mode,
EC oscillator)
VDD = 3.3V
VDD = 2.5V
FOSC = 40 MHz
(PRI_IDLE mode,
EC oscillator)
VDD = 3.3V
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
DS39682E-page 310
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Typ
Max
Units
Conditions
4.1
8.3
mA
-40°C
3.8
7.7
mA
+25°C
3.8
7.7
mA
+85°C
4.1
8.3
mA
-40°C
Supply Current (IDD)(2)
All devices
All devices
All devices
All devices
Note 1:
2:
3:
3.8
7.7
mA
+25°C
3.8
7.7
mA
+85°C
66
169
μA
-40°C
79
195
μA
+25°C
97
271
μA
+85°C
67
268
μA
-40°C
81
296
μA
+25°C
100
362
μA
+85°C
VDD = 2.5V
FOSC = 32 kHz
(SEC_RUN mode,
Timer1 as clock)
VDD = 3.3V
VDD = 2.5V
FOSC = 32 kHz
(SEC_IDLE mode,
Timer1 as clock)
VDD = 3.3V
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
© 2009 Microchip Technology Inc.
DS39682E-page 311
PIC18F45J10 FAMILY
24.2
DC Characteristics:
PIC18F45J10 Family
(Industrial)
Param
No.
D022
(ΔIWDT)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Device
Timer1 Oscillator
A/D Converter
3:
Max
Units
Conditions
-40°C
+25°C
+85°C
-40°C
D026
(ΔIAD)
2:
Typ
Module Differential Currents (ΔIWDT, ΔIOSCB, ΔIAD)
6.5
μA
Watchdog Timer 3.2
3.2
6.5
μA
5.1
10.3
μA
3.5
7.1
μA
D025
(ΔIOSCB)
Note 1:
Power-Down and Supply Current
PIC18F24J10/25J10/44J10/45J10 (Industrial)
PIC18LF24J10/25J10/44J10/45J10 (Industrial) (Continued)
VDD = 2.5V
3.5
5.5
8.4
7.1
11.2
17
μA
μA
μA
+25°C
+85°C
-40°C
VDD = 3.3V
11.5
13.2
9.6
24
30
20
μA
μA
μA
+25°C
+85°C
-40°C
VDD = 2.5V
32 kHz on Timer1(3)
12.4
14.1
1.0
25
29
5
μA
μA
μA
+25°C
+85°C
-40°C to +85°C
VDD = 3.3V
32 kHz on Timer1(3)
1.2
5
μA
-40°C to +85°C
VDD = 2.5V
VDD = 3.3V
A/D on, not converting
The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with
the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS and all features that add delta
current disabled (such as WDT, Timer1 oscillator, etc.).
The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading
and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on
the current consumption.
The test conditions for all IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD;
MCLR = VDD; WDT enabled/disabled as specified.
Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature
crystals are available at a much higher cost.
DS39682E-page 312
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.3
DC Characteristics: PIC18F45J10 Family (Industrial)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
DC CHARACTERISTICS
Param
Symbol
No.
VIL
Characteristic
Min
Max
Units
Conditions
VSS
0.15 VDD
V
VDD < 3.3V
—
0.8
V
3.3V ≤ VDD ≤ 3.6V
VSS
0.2 VDD
V
Input Low Voltage
All I/O Ports:
D030
with TTL Buffer
D030A
D031
with Schmitt Trigger Buffer
D032
MCLR
VSS
0.2 VDD
V
D033
OSC1
VSS
0.3 VDD
V
HS, HSPLL modes
D033A
OSC1
VSS
0.2 VDD
V
EC, ECPLL modes(1)
T1CKI
VSS
0.3
V
0.25 VDD + 0.8V
VDD
V
VDD < 3.3V
2.0
VDD
V
3.3V ≤ VDD ≤ 3.6V
0.8 VDD
VDD
V
D034
VIH
Input High Voltage
I/O Ports with non 5.5V
Tolerance:(4)
D040
with TTL Buffer
D040A
D041
with Schmitt Trigger Buffer
I/O Ports with 5.5V
Tolerance:(4)
Dxxx
with TTL Buffer
DxxxA
0.25 VDD + 0.8V
5.5
V
VDD < 3.3V
2.0
5.5
V
3.3V ≤ VDD ≤ 3.6V
0.8 VDD
5.5
V
D042
MCLR
0.8 VDD
VDD
V
D043
OSC1
0.7 VDD
VDD
V
HS, HSPLL modes
D043A
OSC1
0.8 VDD
VDD
V
EC, ECPLL modes
D044
T1CKI
1.6
VDD
V
Dxxx
with Schmitt Trigger Buffer
IIL
Input Leakage
Current(2,3)
D060
I/O Ports with non 5.5V
Tolerance(4)
—
±0.2
μA
VSS ≤ VPIN ≤ VDD,
Pin at high-impedance
D060A
I/O Ports with 5.5V
Tolerance(4)
—
±0.2
μA
VSS ≤ VPIN ≤ 5.5V,
Pin at high-impedance
D061
MCLR
—
±0.2
μA
Vss ≤ VPIN ≤ VDD
OSC1
—
±0.2
μA
Vss ≤ VPIN ≤ VDD
30
240
μA
VDD = 3.3V, VPIN = VSS
D063
D070
Note 1:
2:
3:
4:
IPU
Weak Pull-up Current
IPURB
PORTB Weak Pull-up Current
In RC oscillator configuration, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PIC® device be driven with an external clock while in RC mode.
The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input
voltages.
Negative current is defined as current sourced by the pin.
Refer to Table 10-2 for the pins that have corresponding tolerance limits.
© 2009 Microchip Technology Inc.
DS39682E-page 313
PIC18F45J10 FAMILY
24.3
DC Characteristics: PIC18F45J10 Family (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
DC CHARACTERISTICS
Param
Symbol
No.
VOL
D080
D083
VOH
D090
D092
Characteristic
Min
Max
Units
Conditions
I/O Ports (PORTB, PORTC)
—
0.4
V
IOL = 8.5 mA, VDD 3.3V
-40°C to +85°C
I/O Ports (PORTA, PORTD,
PORTE)
—
0.4
V
IOL = 3.4 mA, VDD 3.3V
-40°C to +85°C
OSC2/CLKO
(EC mode)
—
0.4
V
IOL = 1.6 mA, VDD 3.3V
-40°C to +85°C
I/O Ports (PORTB, PORTC)
2.4
—
V
IOH = -6 mA, VDD 3.3V
-40°C to +85°C
I/O Ports (PORTA, PORTD,
PORTE)
2.4
—
V
IOH = -2 mA, VDD 3.3V
-40°C to +85°C
OSC2/CLKO
(EC mode)
2.4
—
V
IOH = 1.0 mA, VDD 3.3V
-40°C to +85°C
Output Low Voltage
Output High Voltage(3)
Capacitive Loading Specs
on Output Pins
D100(4) COSC2
OSC2 Pin
—
15
pF
In HS mode when
external clock is used to drive
OSC1
D101
CIO
All I/O Pins
—
50
pF
To meet the AC Timing
Specifications
D102
CB
SCLx, SDAx
—
400
pF
I2C™ Specification
Note 1:
2:
3:
4:
In RC oscillator configuration, the OSC1/CLKI pin is a Schmitt Trigger input. It is not recommended that the
PIC® device be driven with an external clock while in RC mode.
The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified
levels represent normal operating conditions. Higher leakage current may be measured at different input
voltages.
Negative current is defined as current sourced by the pin.
Refer to Table 10-2 for the pins that have corresponding tolerance limits.
DS39682E-page 314
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 24-1:
MEMORY PROGRAMMING REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
DC CHARACTERISTICS
Param
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
Program Flash Memory
D130
EP
Cell Endurance
100
1K
—
D131
VPR
VDD for Read
VMIN
—
3.6
V
VMIN = Minimum operating
voltage
VDD
2.7
—
3.6
V
PIC18FXXJ10
VDDCORE
PIC18LFXXJ10
D132B VPEW
E/W -40°C to +85°C
Voltage for Self-Timed Erase or
Write:
2.25
—
2.7
V
D133A TIW
Self-Timed Write Cycle Time
—
2.8
—
ms
D133B TIE
Self-Timed Page Erased Cycle
Time
—
33.0
—
ms
D134
TRETD Characteristic Retention
20
—
—
Year Provided no other
specifications are violated
D135
IDDP
—
10
—
mA
Supply Current during
Programming
† Data in “Typ” column is at 3.3V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
© 2009 Microchip Technology Inc.
DS39682E-page 315
PIC18F45J10 FAMILY
TABLE 24-2:
COMPARATOR SPECIFICATIONS
Operating Conditions: 3.0V < VDD < 3.6V, -40°C < TA < +85°C (unless otherwise stated)
Param
No.
Sym
Characteristics
Min
Typ
Max
Units
D300
VIOFF
Input Offset Voltage
—
±5.0
±25
mV
D301
VICM
Input Common Mode Voltage*
0
—
VDD – 1.5
V
D302
CMRR
Common Mode Rejection Ratio*
55
—
—
dB
D303
TRESP
Response Time(1)*
—
150
400
ns
D304
TMC2OV
Comparator Mode Change to
Output Valid*
—
—
10
μs
D305
VIRV
Internal Reference Voltage
—
1.2
—
V
*
Note 1:
Comments
These parameters are characterized but not tested.
Response time measured with one comparator input at (VDD – 1.5)/2, while the other input transitions
from VSS to VDD.
TABLE 24-3:
VOLTAGE REFERENCE SPECIFICATIONS
Operating Conditions: 3.0V < VDD < 3.6V, -40°C < TA < +85°C (unless otherwise stated)
Param
No.
Sym
Characteristics
Min
Typ
Max
Units
D310
VRES
Resolution
VDD/24
—
VDD/32
LSb
D311
VRAA
Absolute Accuracy
—
—
1/2
LSb
D312
VRUR
Unit Resistor Value (R)
—
2k
—
Ω
310
TSET
Settling Time(1)
—
—
10
μs
Note 1:
Comments
Settling time measured while CVRR = 1 and CVR<3:0> transitions from ‘0000’ to ‘1111’.
TABLE 24-4:
INTERNAL VOLTAGE REGULATOR SPECIFICATIONS
Operating Conditions: -40°C < TA < +85°C (unless otherwise stated)
Param
No.
*
Sym
Characteristics
Min
Typ
Max
Units
VRGOUT
Regulator Output Voltage
—
2.5
—
V
CEFC
External Filter Capacitor
Value
4.7
10
—
μF
Comments
Series resistance < 3 Ohm
recommended;
< 5 Ohm required.
These parameters are characterized but not tested. Parameter numbers not yet assigned for these
specifications.
DS39682E-page 316
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.4
24.4.1
AC (Timing) Characteristics
TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created
following one of the following formats:
1. TppS2ppS
2. TppS
T
F
Frequency
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
ck
CLKO
cs
CS
di
SDI
do
SDO
dt
Data in
io
I/O port
mc
MCLR
Uppercase letters and their meanings:
S
F
Fall
H
High
I
Invalid (High-impedance)
L
Low
I2C only
AA
output access
BUF
Bus free
TCC:ST (I2C specifications only)
CC
HD
Hold
ST
DAT
DATA input hold
STA
Start condition
© 2009 Microchip Technology Inc.
3. TCC:ST
4. Ts
(I2C specifications only)
(I2C specifications only)
T
Time
osc
rd
rw
sc
ss
t0
t1
wr
OSC1
RD
RD or WR
SCK
SS
T0CKI
T1CKI
WR
P
R
V
Z
Period
Rise
Valid
High-impedance
High
Low
High
Low
SU
Setup
STO
Stop condition
DS39682E-page 317
PIC18F45J10 FAMILY
24.4.2
TIMING CONDITIONS
The temperature and voltages specified in Table 24-5
apply to all timing specifications unless otherwise
noted. Figure 24-3 specifies the load conditions for the
timing specifications.
TABLE 24-5:
TEMPERATURE AND VOLTAGE SPECIFICATIONS – AC
AC CHARACTERISTICS
FIGURE 24-3:
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Operating voltage VDD range as described in DC spec Section 24.1 and
Section 24.3.
LOAD CONDITIONS FOR DEVICE TIMING SPECIFICATIONS
Load Condition 2
Load Condition 1
VDD/2
RL
CL
Pin
VSS
CL
Pin
RL = 464Ω
VSS
DS39682E-page 318
CL = 50 pF
for all pins except OSC2/CLKO
and including D and E outputs as ports
CL = 15 pF
for OSC2/CLK0
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
24.4.3
TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 24-4:
EXTERNAL CLOCK TIMING (ALL MODES EXCEPT PLL)
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
4
3
4
2
CLKO
TABLE 24-6:
Param.
No.
1A
EXTERNAL CLOCK TIMING REQUIREMENTS
Symbol
FOSC
Characteristic
Min
Max
Units
External CLKI Frequency(1)
DC
40
MHz
TOSC
EC Oscillator mode
4
25
MHz
HS Oscillator mode
External CLKI Period(1)
25
—
ns
EC Oscillator mode
Oscillator Period(1)
25
250
ns
HS Oscillator mode
Oscillator Frequency
1
(1)
Conditions
Time(1)
2
TCY
Instruction Cycle
100
—
ns
TCY = 4/FOSC, Industrial
3
TOSL,
TOSH
External Clock in (OSC1)
High or Low Time
10
—
ns
EC Oscillator mode
4
TOSR,
TOSF
External Clock in (OSC1)
Rise or Fall Time
—
7.5
ns
EC Oscillator mode
Note 1:
Instruction cycle period (TCY) equals four times the input oscillator time base period for all configurations.
All specified values are based on characterization data for that particular oscillator type under standard
operating conditions with the device executing code. Exceeding these specified limits may result in an
unstable oscillator operation and/or higher than expected current consumption. All devices are tested to
operate at “min.” values with an external clock applied to the OSC1/CLKI pin. When an external clock input
is used, the “max.” cycle time limit is “DC” (no clock) for all devices.
© 2009 Microchip Technology Inc.
DS39682E-page 319
PIC18F45J10 FAMILY
TABLE 24-7:
Param
No.
PLL CLOCK TIMING SPECIFICATIONS (VDD = 2.5V TO 3.6V)
Sym
Characteristic
Min
Typ†
Max
Units
MHz
MHz
F10
F11
FOSC Oscillator Frequency Range
FSYS On-Chip VCO System Frequency
4
20
—
—
10
40
F12
ΤRC
PLL Start-up Time (lock time)
—
—
2 ms
ΔCLK
CLKO Stability (Jitter)
-2
—
+2
F13
Conditions
%
† Data in “Typ” column is at 5V, 25°C, unless otherwise stated. These parameters are for design guidance
only and are not tested.
TABLE 24-8:
AC CHARACTERISTICS: INTERNAL RC ACCURACY
PIC18F24J10/25J10/44J10/45J10 (INDUSTRIAL)
Param
No.
Note 1:
Characteristic
Min
Typ
Max
Units
INTRC Accuracy @ Freq = 31 kHz(1)
21.7
—
40.3
kHz
Conditions
Change of INTRC frequency as VDD core changes.
DS39682E-page 320
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-5:
CLKO AND I/O TIMING
Q1
Q4
Q2
Q3
OSC1
11
10
CLKO
13
14
19
12
18
16
I/O pin
(Input)
15
17
I/O pin
(Output)
New Value
Old Value
20, 21
Refer to Figure 24-3 for load conditions.
Note:
TABLE 24-9:
Param
No.
CLKO AND I/O TIMING REQUIREMENTS
Symbol
Characteristic
Min
Typ
Max
—
75
200
Units Conditions
10
TOSH2CKL OSC1 ↑ to CLKO ↓
11
TOSH2CKH OSC1 ↑ to CLKO ↑
—
75
200
ns
12
TCKR
CLKO Rise Time
—
15
30
ns
13
TCKF
CLKO Fall Time
—
15
30
ns
14
TCKL2IOV CLKO ↓ to Port Out Valid
—
—
0.5 TCY + 20
ns
15
TIOV2CKH Port In Valid before CLKO ↑
16
TCKH2IOI
17
TOSH2IOV OSC1 ↑ (Q1 cycle) to Port Out Valid
18
TOSH2IOI
18A
Port In Hold after CLKO ↑
OSC1 ↑ (Q2 cycle) to Port Input Invalid
(I/O in hold time)
ns
0.25 TCY + 25
—
—
ns
0
—
—
ns
—
50
150
ns
100
—
—
ns
200
—
—
ns
19
TIOV2OSH Port Input Valid to OSC1 ↑
(I/O in setup time)
0
—
—
ns
20
TIOR
—
—
6
ns
Port Output Rise Time
21
TIOF
Port Output Fall Time
—
—
5
ns
22†
TINP
INTx pin High or Low Time
TCY
—
—
ns
TRBP
RB<7:4> Change INTx High or Low Time
TCY
—
—
ns
23†
† These parameters are asynchronous events not related to any internal clock edges.
© 2009 Microchip Technology Inc.
DS39682E-page 321
PIC18F45J10 FAMILY
FIGURE 24-6:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
Oscillator
Time-out
Internal
Reset
Watchdog
Timer
Reset
31
34
34
I/O pins
Note:
Refer to Figure 24-3 for load conditions.
FIGURE 24-7:
BROWN-OUT RESET TIMING
BVDD
VDD
VBGAP = 1.2V
VIRVST
Enable Internal
Reference Voltage
Internal Reference
Voltage Stable
TABLE 24-10: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
Symbol
No.
Characteristic
Min
Typ
Max
Units
30
TMCL
MCLR Pulse Width (low)
2
—
—
μs
31
TWDT
Watchdog Timer Time-out Period
(no postscaler)
2.8
4.1
5.4
ms
32
TOST
Oscillation Start-up Timer Period
1024 TOSC
—
1024 TOSC
—
33
TPWRT
Power-up Timer Period
46.2
66
85.8
ms
34
TIOZ
I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
—
2
—
μs
38
TCSD
CPU Start-up Time
—
200
—
μs
DS39682E-page 322
Conditions
TOSC = OSC1 period
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-8:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
41
40
42
T1OSO/T1CKI
46
45
47
48
TMR0 or
TMR1
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-11: TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Param
No.
Symbol
Characteristic
40
TT0H
T0CKI High Pulse Width
41
TT0L
T0CKI Low Pulse Width
42
TT0P
T0CKI Period
No prescaler
With prescaler
No prescaler
With prescaler
No prescaler
With prescaler
45
TT1H
T1CKI High
Time
Synchronous, no prescaler
T1CKI Low
Time
Synchronous, no prescaler
Synchronous, with prescaler
Asynchronous
46
47
TT1L
Units
0.5 TCY + 20
—
ns
10
—
ns
0.5 TCY + 20
—
ns
10
—
ns
TCY + 10
—
ns
Greater of:
20 ns or
(TCY + 40)/N
—
ns
0.5 TCY + 20
—
ns
10
—
ns
30
—
ns
—
ns
Synchronous, with prescaler
10
—
ns
Asynchronous
30
—
ns
Synchronous
Greater of:
20 ns or
(TCY + 40)/N
—
ns
TT1P
T1CKI Input
Period
FT 1
T1CKI Oscillator Input Frequency Range
TCKE2TMRI Delay from External T1CKI Clock Edge to
Timer Increment
© 2009 Microchip Technology Inc.
Max
0.5 TCY + 5
Asynchronous
48
Min
60
—
ns
DC
50
kHz
2 TOSC
7 TOSC
—
Conditions
N = prescale
value
(1, 2, 4,..., 256)
N = prescale
value
(1, 2, 4, 8)
DS39682E-page 323
PIC18F45J10 FAMILY
FIGURE 24-9:
CAPTURE/COMPARE/PWM TIMINGS (INCLUDING ECCP MODULE)
CCPx
(Capture Mode)
50
51
52
CCPx
(Compare or PWM Mode)
54
53
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-12: CAPTURE/COMPARE/PWM REQUIREMENTS (INCLUDING ECCP MODULE)
Param
Symbol
No.
50
51
TCCL
TCCH
Characteristic
Min
Max
Units
CCPx Input Low No prescaler
Time
With prescaler
0.5 TCY + 20
—
ns
10
—
ns
CCPx Input
High Time
0.5 TCY + 20
—
ns
10
—
ns
3 TCY + 40
N
—
ns
No prescaler
With prescaler
TCCP
CCPx Input Period
53
TCCR
CCPx Output Fall Time
—
25
ns
54
TCCF
CCPx Output Fall Time
—
25
ns
52
Conditions
N = prescale
value (1, 4 or 16)
TABLE 24-13: PARALLEL SLAVE PORT REQUIREMENTS
Param.
No.
Symbol
Characteristic
Min
Max
Units
62
TdtV2wrH
Data In Valid before WR ↑ or CS ↑ (setup time)
20
—
ns
63
TwrH2dtI
WR ↑ or CS ↑ to Data–In Invalid (hold time)
20
—
ns
64
TrdL2dtV
RD ↓ and CS ↓ to Data–Out Valid
—
80
ns
65
TrdH2dtI
RD ↑ or CS ↓ to Data–Out Invalid
10
30
ns
66
TibfINH
Inhibit of the IBF Flag bit being Cleared from
WR ↑ or CS ↑
—
3 TCY
DS39682E-page 324
Conditions
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-10:
EXAMPLE SPI™ MASTER MODE TIMING (CKE = 0)
SSx
70
SCKx
(CKP = 0)
71
72
78
79
79
78
SCKx
(CKP = 1)
80
bit 6 - - - - - - 1
MSb
SDOx
LSb
75, 76
SDIx
MSb In
bit 6 - - - - 1
LSb In
74
73
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-14: EXAMPLE SPI™ MODE REQUIREMENTS (CKE = 0)
Param
No.
Symbol
Characteristic
Min
Max Units
70
TSSL2SCH,
TSSL2SCL
SSx ↓ to SCKx ↓ or SCKx ↑ Input
TCY
—
ns
73
TDIV2SCH,
TDIV2SCL
Setup Time of SDIx Data Input to SCKx Edge
20
—
ns
73A
TB2B
Last Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
1.5 TCY + 40
—
ns
74
TSCH2DIL,
TSCL2DIL
Hold Time of SDIx Data Input to SCKx Edge
40
—
ns
75
TDOR
SDOx Data Output Rise Time
—
25
ns
76
TDOF
SDOx Data Output Fall Time
—
25
ns
78
TSCR
SCKx Output Rise Time (Master mode)
—
25
ns
79
TSCF
SCKx Output Fall Time (Master mode)
—
25
ns
80
TSCH2DOV, SDOx Data Output Valid after SCKx Edge
TSCL2DOV
—
50
ns
Note 1:
Conditions
(Note 1)
Only if Parameter #71A and #72A are used.
© 2009 Microchip Technology Inc.
DS39682E-page 325
PIC18F45J10 FAMILY
FIGURE 24-11:
EXAMPLE SPI™ MASTER MODE TIMING (CKE = 1)
SSx
81
SCKx
(CKP = 0)
71
72
79
73
SCKx
(CKP = 1)
80
78
MSb
SDOx
bit 6 - - - - - - 1
LSb
bit 6 - - - - 1
LSb In
75, 76
SDIx
MSb In
74
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-15: EXAMPLE SPI™ MODE REQUIREMENTS (CKE = 1)
Param.
No.
Symbol
Characteristic
Min
Max Units
73
TDIV2SCH,
TDIV2SCL
Setup Time of SDIx Data Input to SCKx Edge
73A
TB2B
Last Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
74
TSCH2DIL,
TSCL2DIL
75
TDOR
76
TDOF
SDOx Data Output Fall Time
—
25
ns
78
TSCR
SCKx Output Rise Time (Master mode)
—
25
ns
79
TSCF
SCKx Output Fall Time (Master mode)
—
25
ns
80
TSCH2DOV, SDOx Data Output Valid after SCKx Edge
TSCL2DOV
—
50
ns
81
TDOV2SCH, SDOx Data Output Setup to SCKx Edge
TDOV2SCL
TCY
—
ns
Note 1:
20
—
ns
1.5 TCY + 40
—
ns
Hold Time of SDIx Data Input to SCKx Edge
40
—
ns
SDOx Data Output Rise Time
—
25
ns
Conditions
(Note 1)
Only if Parameter #71A and #72A are used.
DS39682E-page 326
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-12:
EXAMPLE SPI™ SLAVE MODE TIMING (CKE = 0)
SSx
70
SCKx
(CKP = 0)
83
71
72
78
79
79
78
SCKx
(CKP = 1)
80
MSb
SDOx
LSb
bit 6 - - - - - - 1
75, 76
MSb In
SDIx
SDI
77
bit 6 - - - - 1
LSb In
74
73
Refer to Figure 24-3 for load conditions.
Note:
TABLE 24-16: EXAMPLE SPI™ MODE REQUIREMENTS (CKE = 0)
Param
No.
Symbol
Characteristic
70
TSSL2SCH, SSx ↓ to SCKx ↓ or SCKx ↑ Input
TSSL2SCL
71
TSCH
71A
72
TSCL
72A
Min
TCY
Max Units Conditions
—
ns
SCKx Input High Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
SCKx Input Low Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
20
—
ns
73
TDIV2SCH, Setup Time of SDIx Data Input to SCKx Edge
TDIV2SCL
73A
TB2B
—
ns
74
TSCH2DIL, Hold Time of SDIx Data Input to SCKx Edge
TSCL2DIL
40
—
ns
75
TDOR
SDOx Data Output Rise Time
—
25
ns
76
TDOF
SDOx Data Output Fall Time
—
25
ns
Last Clock Edge of Byte 1 to the First Clock Edge of Byte 2 1.5 TCY + 40
77
TSSH2DOZ SSx ↑ to SDOx Output High-Impedance
10
50
ns
80
TSCH2DOV, SDOx Data Output Valid after SCKx Edge
TSCL2DOV
—
50
ns
83
TSCH2SSH, SSx ↑ after SCKx Edge
TSCL2SSH
1.5 TCY + 40
—
ns
Note 1:
2:
(Note 1)
(Note 1)
(Note 2)
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
© 2009 Microchip Technology Inc.
DS39682E-page 327
PIC18F45J10 FAMILY
FIGURE 24-13:
EXAMPLE SPI™ SLAVE MODE TIMING (CKE = 1)
82
SSx
SCKx
(CKP = 0)
70
83
71
72
SCKx
(CKP = 1)
80
MSb
SDOx
bit 6 - - - - - - 1
LSb
75, 76
SDIx
SDI
Note:
MSb In
77
bit 6 - - - - 1
LSb In
74
Refer to Figure 24-3 for load conditions.
TABLE 24-17: EXAMPLE SPI™ SLAVE MODE REQUIREMENTS (CKE = 1)
Param
No.
Symbol
Characteristic
70
TSSL2SCH, SSx ↓ to SCKx ↓ or SCKx ↑ Input
TSSL2SCL
71
TSCH
71A
72
TSCL
72A
Min
Max Units Conditions
TCY
—
ns
SCKx Input High Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
SCKx Input Low Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
(Note 1)
—
ns
(Note 2)
—
ns
73A
TB2B
74
TSCH2DIL, Hold Time of SDIx Data Input to SCKx Edge
TSCL2DIL
Last Clock Edge of Byte 1 to the First Clock Edge of Byte 2 1.5 TCY + 40
20
75
TDOR
SDOx Data Output Rise Time
—
25
ns
76
TDOF
SDOx Data Output Fall Time
—
25
ns
77
TSSH2DOZ SSx ↑ to SDOx Output High-Impedance
10
50
ns
80
TSCH2DOV, SDOx Data Output Valid after SCKx Edge
TSCL2DOV
—
50
ns
82
TSSL2DOV SDOx Data Output Valid after SSx ↓ Edge
—
50
ns
83
TSCH2SSH, SSx ↑ after SCKx Edge
TSCL2SSH
1.5 TCY + 40
—
ns
Note 1:
2:
(Note 1)
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
DS39682E-page 328
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-14:
I2C™ BUS START/STOP BITS TIMING
SCLx
91
93
90
92
SDAx
Stop
Condition
Start
Condition
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-18: I2C™ BUS START/STOP BITS REQUIREMENTS (SLAVE MODE)
Param.
Symbol
No.
Characteristic
90
TSU:STA
Start Condition
91
THD:STA
92
TSU:STO
93
THD:STO Stop Condition
Max
Units
Conditions
4700
—
ns
Only relevant for Repeated
Start condition
ns
After this period, the first
clock pulse is generated
Setup Time
400 kHz mode
600
—
Start Condition
100 kHz mode
4000
—
Hold Time
400 kHz mode
600
—
Stop Condition
100 kHz mode
4700
—
Setup Time
Hold Time
FIGURE 24-15:
100 kHz mode
Min
400 kHz mode
600
—
100 kHz mode
4000
—
400 kHz mode
600
—
ns
ns
I2C™ BUS DATA TIMING
103
102
100
101
SCLx
90
106
107
91
92
SDAx
In
110
109
109
SDAx
Out
Note:
Refer to Figure 24-3 for load conditions.
© 2009 Microchip Technology Inc.
DS39682E-page 329
PIC18F45J10 FAMILY
TABLE 24-19: I2C™ BUS DATA REQUIREMENTS (SLAVE MODE)
Param.
No.
100
Symbol
THIGH
101
TLOW
102
TR
Characteristic
Clock High Time
Clock Low Time
Min
Max
Units
100 kHz mode
4.0
—
μs
400 kHz mode
0.6
—
μs
MSSP Module
1.5 TCY
—
100 kHz mode
4.7
—
μs
μs
400 kHz mode
1.3
—
MSSP Module
1.5 TCY
—
—
1000
ns
20 + 0.1 CB
300
ns
SDAx and SCLx Rise Time 100 kHz mode
400 kHz mode
103
TF
SDAx and SCLx Fall Time 100 kHz mode
TSU:STA
THD:STA
91
THD:DAT
106
TSU:DAT
107
TSU:STO
92
109
TAA
110
TBUF
D102
CB
Note 1:
2:
CB is specified to be from
10 to 400 pF
—
300
ns
20 + 0.1 CB
300
ns
CB is specified to be from
10 to 400 pF
Start Condition Setup Time 100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
Only relevant for Repeated
Start condition
100 kHz mode
4.0
—
μs
400 kHz mode
0.6
—
μs
100 kHz mode
0
—
ns
400 kHz mode
0
0.9
μs
400 kHz mode
90
Conditions
Start Condition Hold Time
Data Input Hold Time
Data Input Setup Time
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
Stop Condition Setup Time 100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
100 kHz mode
—
3500
ns
400 kHz mode
—
—
ns
Output Valid from Clock
Bus Free Time
Bus Capacitive Loading
100 kHz mode
4.7
—
μs
400 kHz mode
1.3
—
μs
—
400
pF
After this period, the first clock
pulse is generated
(Note 2)
(Note 1)
Time the bus must be free
before a new transmission can
start
As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns)
of the falling edge of SCLx to avoid unintended generation of Start or Stop conditions.
A Fast mode I2C™ bus device can be used in a Standard mode I2C bus system, but the requirement, TSU:DAT ≥ 250 ns,
must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCLx signal.
If such a device does stretch the LOW period of the SCLx signal, it must output the next data bit to the SDAx line,
TR max. + TSU:DAT = 1000 + 250 = 1250 ns (according to the Standard mode I2C bus specification), before the SCLx
line is released.
DS39682E-page 330
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-16:
MASTER SSP I2C™ BUS START/STOP BITS TIMING WAVEFORMS
SCLx
93
91
90
92
SDAx
Stop
Condition
Start
Condition
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-20: MASTER SSP I2C™ BUS START/STOP BITS REQUIREMENTS
Param.
Symbol
No.
90
TSU:STA
Characteristic
Start Condition
100 kHz mode
Setup Time
91
THD:STA Start Condition
Hold Time
92
TSU:STO Stop Condition
Setup Time
93
THD:STO Stop Condition
Hold Time
Note 1:
Min
Max
Units
2(TOSC)(BRG + 1)
—
ns
Only relevant for
Repeated Start
condition
ns
After this period, the
first clock pulse is
generated
400 kHz mode
2(TOSC)(BRG + 1)
—
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
100 kHz mode
2(TOSC)(BRG + 1)
—
400 kHz mode
2(TOSC)(BRG + 1)
—
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
Conditions
ns
ns
Maximum pin capacitance = 10 pF for all I2C™ pins.
FIGURE 24-17:
MASTER SSP I2C™ BUS DATA TIMING
103
102
100
101
SCLx
90
106
91
107
92
SDAx
In
109
109
110
SDAx
Out
Note:
Refer to Figure 24-3 for load conditions.
© 2009 Microchip Technology Inc.
DS39682E-page 331
PIC18F45J10 FAMILY
TABLE 24-21: MASTER SSP I2C™ BUS DATA REQUIREMENTS
Param.
Symbol
No.
100
101
THIGH
TLOW
Characteristic
Min
Max
Units
Clock High Time 100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
ms
Clock Low Time 100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
(1)
2(TOSC)(BRG + 1)
—
ms
—
1000
ns
20 + 0.1 CB
300
ns
—
300
ns
1 MHz mode
102
TR
SDAx and SCLx 100 kHz mode
Rise Time
400 kHz mode
1 MHz mode(1)
103
90
91
106
107
92
109
110
D102
Note 1:
2:
TF
TSU:STA
SDAx and SCLx 100 kHz mode
Fall Time
400 kHz mode
Start Condition
Setup Time
THD:STA Start Condition
Hold Time
THD:DAT Data Input
Hold Time
TSU:DAT
Data Input
Setup Time
TSU:STO Stop Condition
Setup Time
TAA
TBUF
CB
Output Valid
from Clock
Bus Free Time
—
300
ns
20 + 0.1 CB
300
ns
1 MHz mode(1)
—
100
ns
100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
ms
100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
ms
100 kHz mode
0
—
ns
400 kHz mode
0
0.9
ms
1 MHz mode(1)
—
—
ns
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
1 MHz mode(1)
—
—
ns
100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
1 MHz mode(1)
2(TOSC)(BRG + 1)
—
ms
100 kHz mode
—
3500
ns
400 kHz mode
—
1000
ns
(1)
1 MHz mode
—
—
ns
100 kHz mode
4.7
—
ms
400 kHz mode
1.3
—
ms
1 MHz mode(1)
—
—
ms
—
400
pF
Bus Capacitive Loading
Conditions
CB is specified to be from
10 to 400 pF
CB is specified to be from
10 to 400 pF
Only relevant for
Repeated Start
condition
After this period, the first
clock pulse is generated
(Note 2)
Time the bus must be free
before a new transmission
can start
Maximum pin capacitance = 10 pF for all I2C™ pins.
A Fast mode I2C bus device can be used in a Standard mode I2C bus system, but parameter #107 ≥ 250 ns
must then be met. This will automatically be the case if the device does not stretch the LOW period of the
SCLx signal. If such a device does stretch the LOW period of the SCLx signal, it must output the next data
bit to the SDAx line, parameter #102 + parameter #107 = 1000 + 250 = 1250 ns (for 100 kHz mode), before
the SCLx line is released.
DS39682E-page 332
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
FIGURE 24-18:
EUSART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
TX/CK
pin
121
121
RX/DT
pin
120
Note:
122
Refer to Figure 24-3 for load conditions.
TABLE 24-22: EUSART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
Max
Units
120
TCKH2DTV SYNC XMIT (MASTER and SLAVE)
Clock High to Data Out Valid
—
40
ns
121
TCKRF
Clock Out Rise Time and Fall Time (Master mode)
—
20
ns
122
TDTRF
Data Out Rise Time and Fall Time
—
20
ns
FIGURE 24-19:
Conditions
EUSART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
TX/CK
pin
125
RX/DT
pin
126
Note:
Refer to Figure 24-3 for load conditions.
TABLE 24-23: EUSART SYNCHRONOUS RECEIVE REQUIREMENTS
Param.
No.
Symbol
Characteristic
125
TDTV2CKL SYNC RCV (MASTER and SLAVE)
Data Hold before CK ↓ (DT hold time)
126
TCKL2DTL
Data Hold after CK ↓ (DT hold time)
© 2009 Microchip Technology Inc.
Min
Max
Units
10
—
ns
15
—
ns
Conditions
DS39682E-page 333
PIC18F45J10 FAMILY
TABLE 24-24: A/D CONVERTER CHARACTERISTICS: PIC18F24J10/25J10/44J10/45J10 (INDUSTRIAL)
Param
Symbol
No.
Characteristic
Min
Typ
Max
Units
—
—
10
bit
Conditions
ΔVREF ≥ 3.0V
A01
NR
Resolution
A03
EIL
Integral Linearity Error
—
—
<±1
LSb ΔVREF ≥ 3.0V
A04
EDL
Differential Linearity Error
—
—
<±1
LSb ΔVREF ≥ 3.0V
A06
EOFF
Offset Error
—
—
<±3
LSb ΔVREF ≥ 3.0V
A07
EGN
Gain Error
—
—
<±3
LSb ΔVREF ≥ 3.0V
A10
—
Monotonicity
—
VSS ≤ VAIN ≤ VREF
A20
ΔVREF
Reference Voltage Range
(VREFH – VREFL)
1.8
3
—
—
—
—
V
V
VDD < 3.0V
VDD ≥ 3.0V
A21
VREFH
Reference Voltage High
VSS
—
VREFH
V
A22
VREFL
Reference Voltage Low
VSS – 0.3V
—
VDD – 3.0V
V
A25
VAIN
Analog Input Voltage
VREFL
—
VREFH
V
A30
ZAIN
Recommended Impedance of
Analog Voltage Source
—
—
2.2
kΩ
A50
IREF
VREF Input Current(2)
—
—
—
—
5
150
μA
μA
Note 1:
2:
3:
Guaranteed(1)
During VAIN acquisition.
During A/D conversion
cycle.
The A/D conversion result never decreases with an increase in the input voltage and has no missing codes.
VREFH current is from RA3/AN3/VREF+ pin or VDD, whichever is selected as the VREFH source.
VREFL current is from RA2/AN2/VREF- pin or VSS, whichever is selected as the VREFL source.
Maximum allowed impedance is 8.8 kΩ. This requires higher acquisition time than described in the A/D
chapter.
FIGURE 24-20:
A/D CONVERSION TIMING
BSF ADCON0, GO
(Note 2)
131
Q4
A/D CLK
130
132
9
A/D DATA
8
7
...
...
2
1
0
OLD_DATA
ADRES
NEW_DATA
TCY
ADIF
GO
DONE
SAMPLING STOPPED
SAMPLE
Note
1:
If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts.
This allows the SLEEP instruction to be executed.
2:
This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
DS39682E-page 334
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
TABLE 24-25: A/D CONVERSION REQUIREMENTS
Param
Symbol
No.
Characteristic
Min
Max
Units
130
TAD
A/D Clock Period
0.7
25.0(1)
μs
131
TCNV
Conversion Time
(not including acquisition time) (Note 2)
11
12
TAD
132
TACQ
Acquisition Time (Note 3)
1.4
—
μs
135
TSWC
Switching Time from Convert → Sample
—
(Note 4)
Note 1:
2:
3:
4:
Conditions
TOSC based, VREF ≥ 2.0V
-40°C to +85°C
The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.
ADRES registers may be read on the following TCY cycle.
The time for the holding capacitor to acquire the “New” input voltage when the voltage changes full scale
after the conversion (VDD to VSS or VSS to VDD). The source impedance (RS) on the input channels is 50Ω.
On the following cycle of the device clock.
© 2009 Microchip Technology Inc.
DS39682E-page 335
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 336
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
25.0
PACKAGING INFORMATION
25.1
Package Marking Information
28-Lead SPDIP
Example
PIC18F24J10
-I/SP e3
0910017
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
28-Lead SOIC
Example
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
YYWWNNN
28-Lead SSOP
Example
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
PIC18F24J10
-I/SS e3
0910017
Example
28-Lead QFN
XXXXXXXX
XXXXXXXX
YYWWNNN
18F24J10
-I/ML e3
0910017
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
PIC18F24J10-I/SO e3
0910017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
© 2009 Microchip Technology Inc.
DS39682E-page 337
PIC18F45J10 FAMILY
Package Marking Information (Continued)
40-Lead PDIP
Example
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
YYWWNNN
44-Lead QFN
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
44-Lead TQFP
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
DS39682E-page 338
PIC18F44J10-I/P e3
0910017
Example
18F44J10
-I/ML e3
0910017
Example
18F45J10
I/PT e3
0910017
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
25.2
Package Details
The following sections give the technical details of the packages.
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DS39682E-page 348
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
APPENDIX A:
REVISION HISTORY
Revision A (March 2005)
Original data sheet for PIC18F45J10 family devices.
Revision B (November 2006)
Packaging diagrams have been updated.
Revision C (January 2007)
Packaging diagrams have been updated.
Revision D (November 2008)
Electrical characteristics and packaging diagrams have
been updated. Minor edits to text throughout document.
Revision E (May 2009)
Pin diagrams have been edited to indicate 5.5V tolerant
input pins. Packaging diagrams have been updated.
Section 2.0 “Guidelines for Getting Started with
PIC18FJ Microcontrollers” has been added. Minor text
edits throughout the document.
© 2009 Microchip Technology Inc.
DS39682E-page 349
PIC18F45J10 FAMILY
APPENDIX B:
migrating an application across device families to
achieve a new design goal. These are summarized in
Table B-1. The areas of difference which could be a
major impact on migration are discussed in greater
detail later in this section.
MIGRATION
BETWEEN HIGH-END
DEVICE FAMILIES
Devices in the PIC18F45J10 family and PIC18F4520
families are very similar in their functions and feature
sets. However, there are some potentially important
differences which should be considered when
TABLE B-1:
NOTABLE DIFFERENCES BETWEEN PIC18F45J10 AND PIC18F4520 FAMILIES
Characteristic
Operating Frequency
Supply Voltage
Operating Current
Program Memory Endurance
I/O Sink/Source at 25 mA
Input Voltage Tolerance on I/O pins
I/O
Pull-ups
Oscillator Options
Program Memory Retention
Programming Time (Normalized)
PIC18F45J10 Family
PIC18F4520 Family
40 MHz @ 2.15V
40 MHz @ 4.2V
2.0V-3.6V
2.0V-5.5V
Low
Lower
1,000 write/erase cycles (typical)
100,000 write/erase cycles (typical)
PORTB and PORTC only
All ports
5.5V on digital only pins
VDD on all I/O pins
32
36
PORTB
PORTB
Limited options
(EC, HS, fixed 32 kHz INTRC)
More options (EC, HS, XT, LP, RC,
PLL, flexible INTRC)
10 years (minimum)
40 years (minimum)
156 μs/byte (10 ms/64-byte block)
15.6 μs/byte (1 ms/64-byte block)
Low Voltage, Key Sequence
VPP and LVP
Single block, all or nothing
Multiple code protection blocks
Stored in last 4 words of
Program Memory space
Stored in Configuration Space,
starting at 300000h
200 μs (typical)
10 μs (typical)
Power-up Timer
Always on
Configurable
Data EEPROM
Not available
Available
Programming Entry
Code Protection
Configuration Words
Start-up Time from Sleep
Brown-out Reset
LVD
A/D Calibration
Simple
BOR(1)
Programmable BOR
Not available
Available
Required
Not required
In-Circuit Emulation
Not available
Available
TMR3
Not available
Available
Available(2)
Not available
Second MSSP
Note 1:
2:
Brown-out Reset is not available on PIC18LFXXJ10 devices.
Available on 40/44-pin devices only.
DS39682E-page 350
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
B.1
Power Requirement Differences
The most significant difference between the
PIC18F45J10 family and PIC18F4520 device families
is the power requirements. PIC18F45J10 family
devices are designed on a smaller process; this results
in lower maximum voltage and higher leakage current.
The operating voltage range for PIC18F45J10 family
devices is 2.0V to 3.6V. One of the VDD pins is separated
for the core logic supply (VDDCORE). This pin has specific
voltage and capacitor requirements as described in
Section 24.0 “Electrical Characteristics”.
The current specifications for PIC18F45J10 family
devices are yet to be determined.
B.2
Pin Differences
There are several differences in the pinouts between
the PIC18F45J10 family and the PIC18F4520 families:
• Input voltage tolerance
• Output current capabilities
• Available I/O
Pins on the PIC18F45J10 family that have digital only
input capability will tolerate voltages up to 5.5V and are
thus tolerant to voltages above VDD. Table 10-1 in
Section 10.0 “I/O Ports” contains the complete list.
In addition to input differences, there are output differences as well. Not all I/O pins can source or sink equal
levels of current. Only PORTB and PORTC support the
25 mA source/sink capability that is supported by all
output pins on the PIC18F4520. Table 10-2 in
Section 10.0 “I/O Ports” contains the complete list of
output capabilities.
There are additional differences in how some pin functions are implemented on PIC18F45J10 family
devices. First, the OSC1/OSC2 oscillator pins are
strictly dedicated to the external oscillator function;
there is no option to re-allocate these pins to I/O (RA6
or RA7) as on PIC18F4520 devices. Second, the
MCLR pin is dedicated only to MCLR and cannot be
configured as an input (RE3). Finally, RA4 does not
exist on PIC18F45J10 family devices.
B.3
Oscillator Differences
PIC18F4520 family devices have a greater range of
oscillator options than PIC18F45J10 family devices.
The latter family is limited primarily to operating modes
that support HS and EC oscillators.
In addition, the PIC18F45J10 family has an internal RC
oscillator with only a fixed 32 kHz output. The higher
frequency RC modes of the PIC18F4520 family are not
available.
B.4
Peripherals
The PIC18F45J10 family is able to operate at 40 MHz
down to 2.15 volts unlike the PIC18F4520 family where
40 MHz operation is limited to 4.2 +V applications.
Peripherals must also be considered when making a
conversion between the PIC18F45J10 family and the
PIC18F4520 families:
• Data EEPROM: PIC18F45J10 family devices do
not have this module.
• BOR: PIC18F45J10 family devices do not have a
programmable BOR. Simple brown-out capability
is provided through the use of the internal voltage
regulator (not available in PIC18LFXXJ10
devices).
• LVD: PIC18F45J10 family devices do not have
this module.
• Timer3 (TMR3) has been removed from the
PIC18F45J10 family.
• The T0CKI/C1OUT pins have been moved from
RA4 to RB5.
• The 40/44-pin devices in the PIC18F45J10 family
have a second MSSP module available on pins
RD<3:0>.
All of these pin differences (including power pin
differences) should be accounted for when making a
conversion between PIC18F4520 and PIC18F45J10
family devices.
© 2009 Microchip Technology Inc.
DS39682E-page 351
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 352
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
INDEX
A
A/D ................................................................................... 215
A/D Converter Interrupt, Configuring ....................... 219
Acquisition Requirements ........................................ 220
ADCAL Bit ................................................................ 223
ADCON0 Register .................................................... 215
ADCON1 Register .................................................... 215
ADCON2 Register .................................................... 215
ADRESH Register ............................................ 215, 218
ADRESL Register .................................................... 215
Analog Port Pins, Configuring .................................. 221
Associated Registers ............................................... 223
Automatic Acquisition Time ...................................... 221
Calculating the Minimum Required
Acquisition Time .............................................. 220
Calibration ................................................................ 223
Configuring the Module ............................................ 219
Conversion Clock (TAD) ........................................... 221
Conversion Status (GO/DONE Bit) .......................... 218
Conversions ............................................................. 222
Converter Characteristics ........................................ 334
Operation in Power-Managed Modes ...................... 223
Special Event Trigger (ECCP) ......................... 136, 222
Use of the ECCP2 Trigger ....................................... 222
Absolute Maximum Ratings ............................................. 303
AC (Timing) Characteristics ............................................. 317
Load Conditions for Device
Timing Specifications ...................................... 318
Parameter Symbology ............................................. 317
Temperature and Voltage Specifications ................. 318
Timing Conditions .................................................... 318
Access Bank
Mapping with Indexed Literal Offset Mode ................. 70
ACKSTAT ........................................................................ 182
ACKSTAT Status Flag ..................................................... 182
ADCAL Bit ........................................................................ 223
ADCON0 Register ............................................................ 215
GO/DONE Bit ........................................................... 218
ADCON1 Register ............................................................ 215
ADCON2 Register ............................................................ 215
ADDFSR .......................................................................... 292
ADDLW ............................................................................ 255
ADDULNK ........................................................................ 292
ADDWF ............................................................................ 255
ADDWFC ......................................................................... 256
ADRESH Register ............................................................ 215
ADRESL Register .................................................... 215, 218
Analog-to-Digital Converter. See A/D.
ANDLW ............................................................................ 256
ANDWF ............................................................................ 257
Assembler
MPASM Assembler .................................................. 300
Auto-Wake-up on Sync Break Character ......................... 206
B
Bank Select Register (BSR) ............................................... 58
Baud Rate Generator ....................................................... 178
BC .................................................................................... 257
BCF .................................................................................. 258
BF .................................................................................... 182
BF Status Flag ................................................................. 182
© 2009 Microchip Technology Inc.
Block Diagrams
A/D ........................................................................... 218
Analog Input Model .................................................. 219
Baud Rate Generator .............................................. 178
Capture Mode Operation ......................................... 129
Comparator Analog Input Model .............................. 229
Comparator I/O Operating Modes ........................... 226
Comparator Output .................................................. 228
Comparator Voltage Reference ............................... 232
Comparator Voltage Reference Output
Buffer Example ................................................ 233
Compare Mode Operation ....................................... 130
Device Clock .............................................................. 30
Enhanced PWM ....................................................... 137
EUSART Receive .................................................... 205
EUSART Transmit ................................................... 203
External Power-on Reset Circuit
(Slow VDD Power-up) ........................................ 43
Fail-Safe Clock Monitor ........................................... 245
Generic I/O Port Operation ........................................ 97
Interrupt Logic ............................................................ 84
MSSP (I2C Master Mode) ........................................ 176
MSSP (I2C Mode) .................................................... 159
MSSP (SPI Mode) ................................................... 149
On-Chip Reset Circuit ................................................ 41
PIC18F24J10/25J10 .................................................. 10
PIC18F44J10/45J10 .................................................. 11
PLL ............................................................................ 29
PORTD and PORTE (Parallel Slave Port) ............... 113
PWM Operation (Simplified) .................................... 132
Reads from Flash Program Memory ......................... 75
Single Comparator ................................................... 227
Table Read Operation ............................................... 71
Table Write Operation ............................................... 72
Table Writes to Flash Program Memory .................... 77
Timer0 in 16-Bit Mode ............................................. 116
Timer0 in 8-Bit Mode ............................................... 116
Timer1 ..................................................................... 120
Timer1 (16-Bit Read/Write Mode) ............................ 121
Timer2 ..................................................................... 126
Watchdog Timer ...................................................... 242
BN .................................................................................... 258
BNC ................................................................................. 259
BNN ................................................................................. 259
BNOV .............................................................................. 260
BNZ ................................................................................. 260
BOR. See Brown-out Reset.
BOV ................................................................................. 263
BRA ................................................................................. 261
Break Character (12-Bit) Transmit and Receive .............. 208
BRG. See Baud Rate Generator.
Brown-out Reset (BOR) ..................................................... 43
and On-Chip Voltage Regulator .............................. 243
Disabling in Sleep Mode ............................................ 43
BSF .................................................................................. 261
BTFSC ............................................................................. 262
BTFSS ............................................................................. 262
BTG ................................................................................. 263
BZ .................................................................................... 264
C
C Compilers
MPLAB C18 ............................................................. 300
MPLAB C30 ............................................................. 300
DS39682E-page 353
PIC18F45J10 FAMILY
Calibration (A/D Converter) .............................................. 223
CALL ................................................................................ 264
CALLW ............................................................................. 293
Capture (CCP Module) ..................................................... 129
Associated Registers ............................................... 131
CCP Pin Configuration ............................................. 129
CCPRxH:CCPRxL Registers ................................... 129
Prescaler .................................................................. 129
Software Interrupt .................................................... 129
Capture (ECCP Module) .................................................. 136
Capture/Compare/PWM (CCP) ........................................ 127
Capture Mode. See Capture.
CCP Modules and Timer Resources ....................... 128
CCPRxH Register .................................................... 128
CCPRxL Register ..................................................... 128
Compare Mode. See Compare.
Interactions Between ECCP1/CCP1 and
CCP2 for Timer Resources .............................. 128
Module Configuration ............................................... 128
Clock Sources .................................................................... 30
Default System Clock on Reset ................................. 31
Selection Using OSCCON Register ........................... 31
CLRF ................................................................................ 265
CLRWDT .......................................................................... 265
Code Examples
16 x 16 Signed Multiply Routine ................................ 82
16 x 16 Unsigned Multiply Routine ............................ 82
8 x 8 Signed Multiply Routine .................................... 81
8 x 8 Unsigned Multiply Routine ................................ 81
Changing Between Capture Prescalers ................... 129
Computed GOTO Using an Offset Value ................... 55
Erasing a Flash Program Memory Row ..................... 76
Fast Register Stack .................................................... 55
How to Clear RAM (Bank 1) Using
Indirect Addressing ............................................ 66
Implementing a Real-Time Clock Using
a Timer1 Interrupt Service ............................... 124
Initializing PORTA ...................................................... 98
Initializing PORTB .................................................... 101
Initializing PORTC .................................................... 104
Initializing PORTD .................................................... 107
Initializing PORTE .................................................... 110
Loading the SSP1BUF (SSP1SR) Register ............. 152
Reading a Flash Program Memory Word .................. 75
Saving STATUS, WREG and
BSR Registers in RAM ....................................... 95
Writing to Flash Program Memory ............................. 78
Code Protection ............................................................... 235
COMF ............................................................................... 266
Comparator ...................................................................... 225
Analog Input Connection Considerations ................. 229
Associated Registers ............................................... 229
Configuration ............................................................ 226
Effects of a Reset ..................................................... 228
Interrupts .................................................................. 228
Operation ................................................................. 227
Operation During Sleep ........................................... 228
Outputs .................................................................... 227
Reference ................................................................ 227
External Signal ................................................. 227
Internal Signal .................................................. 227
Response Time ........................................................ 227
Comparator Specifications ............................................... 316
DS39682E-page 354
Comparator Voltage Reference ....................................... 231
Accuracy and Error .................................................. 232
Associated Registers ............................................... 233
Configuring .............................................................. 231
Connection Considerations ...................................... 232
Effects of a Reset .................................................... 232
Operation During Sleep ........................................... 232
Compare (CCP Module) .................................................. 130
Associated Registers ............................................... 131
CCPRx Register ...................................................... 130
Pin Configuration ..................................................... 130
Software Interrupt .................................................... 130
Special Event Trigger .............................................. 130
Timer1 Mode Selection ............................................ 130
Compare (ECCP Module) ................................................ 136
Special Event Trigger ...................................... 136, 222
Computed GOTO ............................................................... 55
Configuration Bits ............................................................ 235
Configuration Register Protection .................................... 247
Context Saving During Interrupts ....................................... 95
CPFSEQ .......................................................................... 266
CPFSGT .......................................................................... 267
CPFSLT ........................................................................... 267
Crystal Oscillator/Ceramic Resonator ................................ 27
Customer Change Notification Service ............................ 363
Customer Notification Service ......................................... 363
Customer Support ............................................................ 363
D
Data Addressing Modes .................................................... 66
Comparing Addressing Modes with the
Extended Instruction Set Enabled ..................... 69
Direct ......................................................................... 66
Indexed Literal Offset ................................................ 68
Instructions Affected .......................................... 68
Indirect ....................................................................... 66
Inherent and Literal .................................................... 66
Data Memory ..................................................................... 58
Access Bank .............................................................. 60
and the Extended Instruction Set .............................. 68
Bank Select Register (BSR) ...................................... 58
General Purpose Registers ....................................... 60
Map for PIC18F45J10 Family .................................... 59
Special Function Registers ........................................ 61
DAW ................................................................................ 268
DC Characteristics ........................................................... 313
Power-Down and Supply Current ............................ 306
Supply Voltage ........................................................ 305
DCFSNZ .......................................................................... 269
DECF ............................................................................... 268
DECFSZ .......................................................................... 269
Default System Clock ........................................................ 31
Development Support ...................................................... 299
Device Overview .................................................................. 7
Core Features .............................................................. 7
Details on Individual Family Members ......................... 8
Features (table) ........................................................... 9
Other Special Features ................................................ 8
Direct Addressing .............................................................. 67
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
E
F
Effect on Standard PIC Instructions ................................. 296
Effects of Power-Managed Modes on
Various Clock Sources ............................................... 32
Electrical Characteristics .................................................. 303
Enhanced Capture/Compare/PWM (ECCP) .................... 135
Associated Registers ............................................... 148
Capture and Compare Modes .................................. 136
Capture Mode. See Capture (ECCP Module).
Outputs and Configuration ....................................... 136
Pin Configurations for ECCP1 Modes ...................... 136
PWM Mode. See PWM (ECCP Module).
Standard PWM Mode ............................................... 136
Timer Resources ...................................................... 136
Enhanced PWM Mode. See PWM (ECCP Module). ........ 137
Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART). See EUSART.
Equations
A/D Acquisition Time ................................................ 220
A/D Minimum Charging Time ................................... 220
Errata ................................................................................... 6
EUSART
Asynchronous Mode ................................................ 203
12-Bit Break Transmit and Receive ................. 208
Associated Registers, Receive ........................ 206
Associated Registers, Transmit ....................... 204
Auto-Wake-up on Sync Break ......................... 206
Receiver ........................................................... 205
Setting Up 9-Bit Mode with
Address Detect ........................................ 205
Transmitter ....................................................... 203
Baud Rate Generator
Operation in Power-Managed Mode ................ 197
Baud Rate Generator (BRG) .................................... 197
Associated Registers ....................................... 198
Auto-Baud Rate Detect .................................... 201
Baud Rate Error, Calculating ........................... 198
Baud Rates, Asynchronous Modes ................. 199
High Baud Rate Select (BRGH Bit) ................. 197
Sampling .......................................................... 197
Synchronous Master Mode ...................................... 209
Associated Registers, Receive ........................ 211
Associated Registers, Transmit ....................... 210
Reception ......................................................... 211
Transmission ................................................... 209
Synchronous Slave Mode ........................................ 212
Associated Registers, Receive ........................ 213
Associated Registers, Transmit ....................... 212
Reception ......................................................... 213
Transmission ................................................... 212
Extended Instruction Set
ADDFSR .................................................................. 292
ADDULNK ................................................................ 292
and Using MPLAB IDE Tools ................................... 298
CALLW ..................................................................... 293
Considerations for Use ............................................ 296
MOVSF .................................................................... 293
MOVSS .................................................................... 294
PUSHL ..................................................................... 294
SUBFSR .................................................................. 295
SUBULNK ................................................................ 295
Syntax ...................................................................... 291
External Clock Input (EC Modes) ....................................... 28
Fail-Safe Clock Monitor ........................................... 235, 245
Interrupts in Power-Managed Modes ...................... 246
POR or Wake-up from Sleep ................................... 246
WDT During Oscillator Failure ................................. 245
Fast Register Stack ........................................................... 55
Firmware Instructions ...................................................... 249
Flash Configuration Words .............................................. 235
Flash Program Memory ..................................................... 71
Associated Registers ................................................. 79
Control Registers ....................................................... 72
EECON1 and EECON2 ..................................... 72
TABLAT (Table Latch) ....................................... 74
TBLPTR (Table Pointer) .................................... 74
Erase Sequence ........................................................ 76
Erasing ...................................................................... 76
Operation During Code-Protect ................................. 79
Reading ..................................................................... 75
Table Pointer
Boundaries Based on Operation ....................... 74
Table Pointer Boundaries .......................................... 74
Table Reads and Table Writes .................................. 71
Write Sequence ......................................................... 77
Writing To .................................................................. 77
Protection Against Spurious Writes ................... 79
Unexpected Termination ................................... 79
Write Verify ........................................................ 79
FSCM. See Fail-Safe Clock Monitor.
© 2009 Microchip Technology Inc.
G
GOTO .............................................................................. 270
H
Hardware Multiplier ............................................................ 81
Introduction ................................................................ 81
Operation ................................................................... 81
Performance Comparison .......................................... 81
I
I/O Ports ............................................................................ 97
I2C Mode (MSSP)
Acknowledge Sequence Timing .............................. 185
Associated Registers ............................................... 192
Baud Rate Generator .............................................. 178
Bus Collision
During a Repeated Start Condition .................. 190
During a Stop Condition .................................. 191
Clock Arbitration ...................................................... 179
Clock Stretching ...................................................... 171
10-Bit Slave Receive Mode (SEN = 1) ............ 171
10-Bit Slave Transmit Mode ............................ 171
7-Bit Slave Receive Mode (SEN = 1) .............. 171
7-Bit Slave Transmit Mode .............................. 171
Clock Synchronization and the CKP Bit .................. 172
Effects of a Reset .................................................... 186
General Call Address Support ................................. 175
I2C Clock Rate w/BRG ............................................ 178
Master Mode ............................................................ 176
Baud Rate Generator ...................................... 178
Operation ......................................................... 177
Reception ........................................................ 182
Repeated Start Condition Timing .................... 181
Start Condition Timing ..................................... 180
Transmission ................................................... 182
DS39682E-page 355
PIC18F45J10 FAMILY
Multi-Master Communication, Bus Collision
and Arbitration .................................................. 186
Multi-Master Mode ................................................... 186
Operation ................................................................. 164
Read/Write Bit Information (R/W Bit) ............... 164, 166
Registers .................................................................. 159
Serial Clock (SCKx/SCLx) ....................................... 166
Slave Mode .............................................................. 164
Addressing ....................................................... 164
Reception ......................................................... 166
Transmission .................................................... 166
Sleep Operation ....................................................... 186
Stop Condition Timing .............................................. 185
INCF ................................................................................. 270
INCFSZ ............................................................................ 271
In-Circuit Debugger .......................................................... 247
In-Circuit Serial Programming (ICSP) ...................... 235, 247
Indexed Literal Offset Addressing
and Standard PIC18 Instructions ............................. 296
Indexed Literal Offset Mode ............................................. 296
Indirect Addressing ............................................................ 67
INFSNZ ............................................................................ 271
Initialization Conditions for All Registers ...................... 47–50
Instruction Cycle ................................................................. 56
Clocking Scheme ....................................................... 56
Instruction Flow/Pipelining ................................................. 56
Instruction Set .................................................................. 249
ADDLW .................................................................... 255
ADDWF .................................................................... 255
ADDWF (Indexed Literal Offset Mode) .................... 297
ADDWFC ................................................................. 256
ANDLW .................................................................... 256
ANDWF .................................................................... 257
BC ............................................................................ 257
BCF .......................................................................... 258
BN ............................................................................ 258
BNC ......................................................................... 259
BNN ......................................................................... 259
BNOV ....................................................................... 260
BNZ .......................................................................... 260
BOV ......................................................................... 263
BRA .......................................................................... 261
BSF .......................................................................... 261
BSF (Indexed Literal Offset Mode) .......................... 297
BTFSC ..................................................................... 262
BTFSS ..................................................................... 262
BTG .......................................................................... 263
BZ ............................................................................ 264
CALL ........................................................................ 264
CLRF ........................................................................ 265
CLRWDT .................................................................. 265
COMF ...................................................................... 266
CPFSEQ .................................................................. 266
CPFSGT .................................................................. 267
CPFSLT ................................................................... 267
DAW ......................................................................... 268
DCFSNZ .................................................................. 269
DECF ....................................................................... 268
DECFSZ ................................................................... 269
Extended Instruction Set .......................................... 291
General Format ........................................................ 251
GOTO ...................................................................... 270
INCF ......................................................................... 270
INCFSZ .................................................................... 271
INFSNZ .................................................................... 271
DS39682E-page 356
IORLW ..................................................................... 272
IORWF ..................................................................... 272
LFSR ....................................................................... 273
MOVF ...................................................................... 273
MOVFF .................................................................... 274
MOVLB .................................................................... 274
MOVLW ................................................................... 275
MOVWF ................................................................... 275
MULLW .................................................................... 276
MULWF .................................................................... 276
NEGF ....................................................................... 277
NOP ......................................................................... 277
Opcode Field Descriptions ....................................... 250
POP ......................................................................... 278
PUSH ....................................................................... 278
RCALL ..................................................................... 279
RESET ..................................................................... 279
RETFIE .................................................................... 280
RETLW .................................................................... 280
RETURN .................................................................. 281
RLCF ....................................................................... 281
RLNCF ..................................................................... 282
RRCF ....................................................................... 282
RRNCF .................................................................... 283
SETF ....................................................................... 283
SETF (Indexed Literal Offset Mode) ........................ 297
SLEEP ..................................................................... 284
Standard Instructions ............................................... 249
SUBFWB ................................................................. 284
SUBLW .................................................................... 285
SUBWF .................................................................... 285
SUBWFB ................................................................. 286
SWAPF .................................................................... 286
TBLRD ..................................................................... 287
TBLWT .................................................................... 288
TSTFSZ ................................................................... 289
XORLW ................................................................... 289
XORWF ................................................................... 290
INTCON Registers ............................................................. 85
Inter-Integrated Circuit. See I2C Mode.
Internal Oscillator Block ..................................................... 30
Internal RC Oscillator
Use with WDT .......................................................... 242
Internet Address .............................................................. 363
Interrupt Sources ............................................................. 235
A/D Conversion Complete ....................................... 219
Capture Complete (CCP) ......................................... 129
Compare Complete (CCP) ....................................... 130
Interrupt-on-Change (RB7:RB4) .............................. 101
INTx Pin ..................................................................... 95
PORTB, Interrupt-on-Change .................................... 95
TMR0 ......................................................................... 95
TMR0 Overflow ........................................................ 117
TMR1 Overflow ........................................................ 119
TMR2-to-PR2 Match (PWM) ............................ 132, 137
Interrupts ............................................................................ 83
Interrupts, Flag Bits
Interrupt-on-Change (RB7:RB4)
Flag (RBIF Bit) ................................................. 101
INTOSC, INTRC. See Internal Oscillator Block.
IORLW ............................................................................. 272
IORWF ............................................................................. 272
IPR Registers ..................................................................... 92
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
L
P
LFSR ................................................................................ 273
Packaging Information ..................................................... 337
Details ...................................................................... 339
Marking .................................................................... 337
Parallel Slave Port (PSP) ......................................... 107, 113
Associated Registers ............................................... 114
CS (Chip Select) ...................................................... 113
PORTD .................................................................... 113
RD (Read Input) ...................................................... 113
Select (PSPMODE Bit) .................................... 107, 113
WR (Write Input) ...................................................... 113
PICSTART Plus Development Programmer .................... 302
PIE Registers ..................................................................... 90
Pin Functions
MCLR .................................................................. 12, 16
OSC1/CLKI .......................................................... 12, 16
OSC2/CLKO ........................................................ 12, 16
RA0/AN0 .............................................................. 13, 17
RA1/AN1 .............................................................. 13, 17
RA2/AN2/VREF-/CVREF ....................................... 13, 17
RA3/AN3/VREF+ .................................................. 13, 17
RA5/AN4/SS1/C2OUT ......................................... 13, 17
RB0/INT0/FLT0/AN12 ......................................... 14, 18
RB1/INT1/AN10 ................................................... 14, 18
RB2/INT2/AN8 ..................................................... 14, 18
RB3/AN9/CCP2 ................................................... 14, 18
RB4/KBI0/AN11 ................................................... 14, 18
RB5/KBI1/C1OUT ...................................................... 18
RB5/KBI1/T0CKI/C1OUT .......................................... 14
RB6/KBI2/PGC .................................................... 14, 18
RB7/KBI3/PGD .................................................... 14, 18
RC0/T1OSO/T1CKI ............................................. 15, 19
RC1/T1OSI/CCP2 ............................................... 15, 19
RC2/CCP1 ................................................................. 15
RC2/CCP1/P1A ......................................................... 19
RC3/SCK1/SCL1 ................................................. 15, 19
RC4/SDI1/SDA1 .................................................. 15, 19
RC5/SDO1 ........................................................... 15, 19
RC6/TX/CK .......................................................... 15, 19
RC7/RX/DT .......................................................... 15, 19
RD0/PSP0/SCK2/SCL2 ............................................. 20
RD1/PSP1/SDI2/SDA2 .............................................. 20
RD2/PSP2/SDO2 ...................................................... 20
RD3/PSP3/SS2 ......................................................... 20
RD4/PSP4 ................................................................. 20
RD5/PSP5/P1B ......................................................... 20
RD6/PSP6/P1C ......................................................... 20
RD7/PSP7/P1D ......................................................... 20
RE0/RD/AN5 ............................................................. 21
RE1/WR/AN6 ............................................................. 21
RE2/CS/AN7 .............................................................. 21
VDD ...................................................................... 15, 21
VDDCORE/VCAP .................................................... 15, 21
VSS ...................................................................... 15, 21
Pinout I/O Descriptions
PIC18F24J10/25J10 .................................................. 12
PIC18F44J10/45J10 .................................................. 16
PIR Registers ..................................................................... 88
PLL Frequency Multiplier ................................................... 29
ECPLL Oscillator Mode ............................................. 29
HSPLL Oscillator Mode ............................................. 29
POP ................................................................................. 278
POR. See Power-on Reset.
M
Master Clear (MCLR) ......................................................... 43
Master Synchronous Serial Port (MSSP). See MSSP.
Memory Organization ......................................................... 51
Data Memory ............................................................. 58
Program Memory ....................................................... 51
Memory Programming Requirements .............................. 315
Microchip Internet Web Site ............................................. 363
MOVF ............................................................................... 273
MOVFF ............................................................................ 274
MOVLB ............................................................................ 274
MOVLW ........................................................................... 275
MOVSF ............................................................................ 293
MOVSS ............................................................................ 294
MOVWF ........................................................................... 275
MPLAB ASM30 Assembler, Linker, Librarian .................. 300
MPLAB ICD 2 In-Circuit Debugger .................................. 301
MPLAB ICE 2000 High-Performance
Universal In-Circuit Emulator ................................... 301
MPLAB Integrated Development
Environment Software .............................................. 299
MPLAB PM3 Device Programmer ................................... 301
MPLAB REAL ICE In-Circuit Emulator System ................ 301
MPLINK Object Linker/MPLIB Object Librarian ............... 300
MSSP
ACK Pulse ........................................................ 164, 166
Control Registers (general) ...................................... 149
I2C Mode. See I2C Mode.
Module Overview ..................................................... 149
SPI Master/Slave Connection .................................. 153
SSPxBUF Register .................................................. 154
SSPxSR Register ..................................................... 154
MULLW ............................................................................ 276
MULWF ............................................................................ 276
N
NEGF ............................................................................... 277
NOP ................................................................................. 277
Notable Differences Between PIC18F4520
and PIC18F45J10 Families ...................................... 350
Oscillator Options ..................................................... 351
Peripherals ............................................................... 351
Pinouts ..................................................................... 351
Power Requirements ............................................... 351
O
Oscillator Configuration ...................................................... 27
EC .............................................................................. 27
ECPLL ........................................................................ 27
HS .............................................................................. 27
HS Modes .................................................................. 27
HSPLL ........................................................................ 27
Internal Oscillator Block ............................................. 30
INTRC ........................................................................ 27
Oscillator Selection .......................................................... 235
Oscillator Start-up Timer (OST) ......................................... 33
Oscillator Switching ............................................................ 30
Oscillator Transitions ......................................................... 31
Oscillator, Timer1 ............................................................. 119
© 2009 Microchip Technology Inc.
DS39682E-page 357
PIC18F45J10 FAMILY
PORTA
Associated Registers ............................................... 100
LATA Register ............................................................ 98
PORTA Register ........................................................ 98
TRISA Register .......................................................... 98
PORTB
Associated Registers ............................................... 103
LATB Register .......................................................... 101
PORTB Register ...................................................... 101
RB7:RB4 Interrupt-on-Change Flag (RBIF Bit) ........ 101
TRISB Register ........................................................ 101
PORTC
Associated Registers ............................................... 106
LATC Register ......................................................... 104
PORTC Register ...................................................... 104
RC3/SCK1/SCL1 Pin ............................................... 166
TRISC Register ........................................................ 104
PORTD
Associated Registers ............................................... 109
LATD Register ......................................................... 107
Parallel Slave Port (PSP) Function .......................... 107
PORTD Register ...................................................... 107
TRISD Register ........................................................ 107
PORTE
Associated Registers ............................................... 112
LATE Register .......................................................... 110
PORTE Register ...................................................... 110
PSP Mode Select (PSPMODE Bit) .......................... 107
TRISE Register ........................................................ 110
Power-Managed Modes ..................................................... 35
and EUSART Operation ........................................... 197
and Multiple Sleep Commands .................................. 36
and PWM Operation ................................................ 147
and SPI Operation ................................................... 157
Clock Transitions and Status Indicators ..................... 36
Entering ...................................................................... 35
Exiting Idle and Sleep Modes .................................... 40
by Reset ............................................................. 40
by WDT Time-out ............................................... 40
Without an Oscillator Start-up Delay .................. 40
Idle Modes ................................................................. 38
PRI_IDLE ........................................................... 39
RC_IDLE ............................................................ 40
SEC_IDLE .......................................................... 39
Run Modes ................................................................. 36
PRI_RUN ........................................................... 36
RC_RUN ............................................................ 37
SEC_RUN .......................................................... 36
Selecting .................................................................... 35
Sleep Mode ................................................................ 38
Summary (table) ........................................................ 35
Power-on Reset (POR) ...................................................... 43
Power-up Timer (PWRT) ........................................... 44
Time-out Sequence .................................................... 44
Power-up Delays ................................................................ 33
Power-up Timer (PWRT) .............................................. 33, 44
Prescaler
Timer2 ...................................................................... 138
Prescaler, Timer0 ............................................................. 117
Prescaler, Timer2 ............................................................. 133
PRI_IDLE Mode ................................................................. 39
PRI_RUN Mode ................................................................. 36
Program Counter ................................................................ 53
PCL, PCH and PCU Registers ................................... 53
PCLATH and PCLATU Registers .............................. 53
DS39682E-page 358
Program Memory
and Extended Instruction Set .................................... 70
Flash Configuration Words ........................................ 52
Instructions ................................................................ 57
Two-Word .......................................................... 57
Interrupt Vector .................................................... 51, 52
Look-up Tables .......................................................... 55
Map and Stack (diagram) .......................................... 51
Memory Maps
Hard Vectors and Configuration Words ............. 52
Reset Vector ........................................................ 51, 52
Program Verification and Code Protection ...................... 247
Programming, Device Instructions ................................... 249
PSP. See Parallel Slave Port.
Pulse-Width Modulation. See PWM (CCP Module)
and PWM (ECCP Module).
PUSH ............................................................................... 278
PUSH and POP Instructions .............................................. 54
PUSHL ............................................................................. 294
PWM (CCP Module)
Associated Registers ............................................... 134
Auto-Shutdown (CCP1 Only) ................................... 133
CCPR1H:CCPR1L Registers ................................... 137
Duty Cycle ....................................................... 132, 138
Example Frequencies/Resolutions .................. 133, 138
Period .............................................................. 132, 137
Setup for Operation ................................................. 133
TMR2-to-PR2 Match ........................................ 132, 137
PWM (ECCP Module) ...................................................... 137
Direction Change in Full-Bridge Output Mode ......... 142
Effects of a Reset .................................................... 147
Enhanced PWM Auto-Shutdown ............................. 144
Full-Bridge Application Example .............................. 142
Full-Bridge Mode ..................................................... 141
Half-Bridge Mode ..................................................... 140
Half-Bridge Output Mode Applications Example ...... 140
Operation in Power-Managed Modes ...................... 147
Operation with Fail-Safe Clock Monitor ................... 147
Output Configurations .............................................. 138
Output Relationships (Active-High) .......................... 139
Output Relationships (Active-Low) .......................... 139
Programmable Dead-Band Delay ............................ 144
Setup for PWM Operation ........................................ 147
Start-up Considerations ........................................... 146
Q
Q Clock .................................................................... 133, 138
R
RAM. See Data Memory.
RBIF Bit ........................................................................... 101
RC_IDLE Mode .................................................................. 40
RC_RUN Mode .................................................................. 37
RCALL ............................................................................. 279
RCON Register
Bit Status During Initialization .................................... 46
Reader Response ............................................................ 364
Register File ....................................................................... 60
Register File Summary ................................................ 62–64
Registers
ADCON0 (A/D Control 0) ......................................... 215
ADCON1 (A/D Control 1) ......................................... 216
ADCON2 (A/D Control 2) ......................................... 217
BAUDCON (Baud Rate Control) .............................. 196
CCP1CON (ECCP1 Control) ................................... 135
CCPxCON (CCPx Control) ...................................... 127
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
CMCON (Comparator Control) ................................ 225
CONFIG1H (Configuration 1 High) .......................... 237
CONFIG1L (Configuration 1 Low) ............................ 237
CONFIG2H (Configuration 2 High) .......................... 239
CONFIG2L (Configuration 2 Low) ............................ 238
CONFIG3H (Configuration 3 High) .......................... 240
CONFIG3L (Configuration 3 Low) ............................ 240
CVRCON (Comparator Voltage
Reference Control) .......................................... 231
DEVID1 (Device ID Register 1) ................................ 241
DEVID2 (Device ID Register 2) ................................ 241
ECCP1DEL (PWM Dead-Band Delay) .................... 144
EECON1 (EEPROM Control 1) .................................. 73
EUSART Receive Status and Control ...................... 195
INTCON (Interrupt Control) ........................................ 85
INTCON2 (Interrupt Control 2) ................................... 86
INTCON3 (Interrupt Control 3) ................................... 87
IPR1 (Peripheral Interrupt Priority 1) .......................... 92
IPR2 (Peripheral Interrupt Priority 2) .......................... 93
IPR3 (Peripheral Interrupt Priority 3) .......................... 93
OSCCON (Oscillator Control) .................................... 32
OSCTUNE (PLL Control) ........................................... 29
PIE1 (Peripheral Interrupt Enable 1) .......................... 90
PIE2 (Peripheral Interrupt Enable 2) .......................... 91
PIE3 (Peripheral Interrupt Enable 3) .......................... 91
PIR1 (Peripheral Interrupt Request (Flag) 1) ............. 88
PIR2 (Peripheral Interrupt Request (Flag) 2) ............. 89
PIR3 (Peripheral Interrupt Request (Flag) 3) ............. 89
RCON (Reset Control) ......................................... 42, 94
SSPxCON1 (MSSPx Control 1, I2C Mode) .............. 161
SSPxCON1 (MSSPx Control 1, SPI Mode) ............. 151
SSPxCON2 (MSSPx Control 2,
I2C Master Mode) ............................................ 162
SSPxCON2 (MSSPx Control 2,
I2C Slave Mode) .............................................. 163
SSPxSTAT (MSSPx Status, I2C Mode) ................... 160
SSPxSTAT (MSSPx Status, SPI Mode) .................. 150
STATUS ..................................................................... 65
STKPTR (Stack Pointer) ............................................ 54
T0CON (Timer0 Control) .......................................... 115
T1CON (Timer1 Control) .......................................... 119
T2CON (Timer2 Control) .......................................... 125
TRISE (PORTE/PSP Control) .................................. 111
TXSTA (EUSART Transmit Status
and Control) ..................................................... 194
WDTCON (Watchdog Timer Control) ...................... 242
RESET ............................................................................. 279
Reset
Brown-out Reset (BOR) ............................................. 41
Configuration Mismatch (CM) .................................... 41
MCLR Reset, During Power-Managed Modes ........... 41
MCLR Reset, Normal Operation ................................ 41
Power-on Reset (POR) .............................................. 41
RESET Instruction ..................................................... 41
Stack Full Reset ......................................................... 41
Stack Underflow Reset .............................................. 41
Watchdog Timer (WDT) Reset ................................... 41
Resets .............................................................................. 235
Brown-out Reset (BOR) ........................................... 235
Oscillator Start-up Timer (OST) ............................... 235
Power-on Reset (POR) ............................................ 235
Power-up Timer (PWRT) ......................................... 235
RETFIE ............................................................................ 280
RETLW ............................................................................ 280
RETURN .......................................................................... 281
Return Address Stack ........................................................ 53
© 2009 Microchip Technology Inc.
Return Stack Pointer (STKPTR) ........................................ 54
Revision History ............................................................... 349
RLCF ............................................................................... 281
RLNCF ............................................................................. 282
RRCF ............................................................................... 282
RRNCF ............................................................................ 283
S
SCKx ............................................................................... 149
SDIx ................................................................................. 149
SDOx ............................................................................... 149
SEC_IDLE Mode ............................................................... 39
SEC_RUN Mode ................................................................ 36
Serial Clock, SCKx .......................................................... 149
Serial Data In (SDIx) ........................................................ 149
Serial Data Out (SDOx) ................................................... 149
Serial Peripheral Interface. See SPI Mode.
SETF ............................................................................... 283
Slave Select (SSx) ........................................................... 149
SLEEP ............................................................................. 284
Sleep
OSC1 and OSC2 Pin States ...................................... 33
Software Simulator (MPLAB SIM) ................................... 300
Special Event Trigger. See Compare (ECCP Module).
Special Event Trigger. See Compare (ECCP/CCP Modules).
Special Features of the CPU ........................................... 235
Special Function Registers ................................................ 61
Map ............................................................................ 61
SPI Mode (MSSP)
Associated Registers ............................................... 158
Bus Mode Compatibility ........................................... 157
Clock Speed and Module Interactions ..................... 157
Effects of a Reset .................................................... 157
Enabling SPI I/O ...................................................... 153
Master Mode ............................................................ 154
Master/Slave Connection ........................................ 153
Operation ................................................................. 152
Operation in Power-Managed Modes ...................... 157
Serial Clock ............................................................. 149
Serial Data In ........................................................... 149
Serial Data Out ........................................................ 149
Slave Mode .............................................................. 155
Slave Select ............................................................. 149
Slave Select Synchronization .................................. 155
SPI Clock ................................................................. 154
Typical Connection .................................................. 153
SSPOV ............................................................................ 182
SSPOV Status Flag ......................................................... 182
SSPxSTAT Register
R/W Bit ............................................................ 164, 166
SSx .................................................................................. 149
Stack Full/Underflow Resets .............................................. 55
STATUS Register .............................................................. 65
SUBFSR .......................................................................... 295
SUBFWB ......................................................................... 284
SUBLW ............................................................................ 285
SUBULNK ........................................................................ 295
SUBWF ............................................................................ 285
SUBWFB ......................................................................... 286
SWAPF ............................................................................ 286
T
Table Pointer Operations (table) ........................................ 74
Table Reads/Table Writes ................................................. 55
TBLRD ............................................................................. 287
TBLWT ............................................................................ 288
DS39682E-page 359
PIC18F45J10 FAMILY
Timer0 .............................................................................. 115
Associated Registers ............................................... 117
Clock Source Select (T0CS Bit) ............................... 116
Operation ................................................................. 116
Overflow Interrupt .................................................... 117
Prescaler .................................................................. 117
Prescaler Assignment (PSA Bit) .............................. 117
Prescaler Select (T0PS2:T0PS0 Bits) ..................... 117
Prescaler. See Prescaler, Timer0.
Reads and Writes in 16-Bit Mode ............................ 116
Source Edge Select (T0SE Bit) ................................ 116
Switching Prescaler Assignment .............................. 117
Timer1 .............................................................................. 119
16-Bit Read/Write Mode ........................................... 121
Associated Registers ............................................... 124
Interrupt .................................................................... 122
Operation ................................................................. 120
Oscillator .......................................................... 119, 121
Layout Considerations ..................................... 122
Oscillator, as Secondary Clock .................................. 30
Overflow Interrupt .................................................... 119
Resetting, Using the ECCP/CCP
Special Event Trigger ....................................... 123
Special Event Trigger (ECCP) ................................. 136
TMR1H Register ...................................................... 119
TMR1L Register ....................................................... 119
Use as a Clock Source ............................................ 122
Use as a Real-Time Clock ....................................... 123
Timer2 .............................................................................. 125
Associated Registers ............................................... 126
Interrupt .................................................................... 126
Operation ................................................................. 125
Output ...................................................................... 126
PR2 Register .................................................... 132, 137
TMR2-to-PR2 Match Interrupt .......................... 132, 137
Timing Diagrams
A/D Conversion ........................................................ 334
Acknowledge Sequence .......................................... 185
Asynchronous Reception ......................................... 206
Asynchronous Transmission .................................... 204
Asynchronous Transmission (Back to Back) ........... 204
Automatic Baud Rate Calculation ............................ 202
Auto-Wake-up Bit (WUE) During
Normal Operation ............................................. 207
Auto-Wake-up Bit (WUE) During Sleep ................... 207
Baud Rate Generator with Clock Arbitration ............ 179
BRG Overflow Sequence ......................................... 202
BRG Reset Due to SDAx Arbitration During
Start Condition ................................................. 189
Brown-out Reset (BOR) ........................................... 322
Bus Collision During a Repeated
Start Condition (Case 1) .................................. 190
Bus Collision During a Repeated
Start Condition (Case 2) .................................. 190
Bus Collision During a
Start Condition (SCLx = 0) ............................... 189
Bus Collision During a
Stop Condition (Case 1) ................................... 191
Bus Collision During a
Stop Condition (Case 2) ................................... 191
Bus Collision During
Start Condition (SDAx Only) ............................ 188
Bus Collision for Transmit and Acknowledge ........... 187
Capture/Compare/PWM
(Including ECCP Module) ................................ 324
DS39682E-page 360
CLKO and I/O .......................................................... 321
Clock Synchronization ............................................. 172
Clock/Instruction Cycle .............................................. 56
EUSART Synchronous Receive (Master/Slave) ...... 333
EUSART Synchronous Transmission
(Master/Slave) ................................................. 333
Example SPI Master Mode (CKE = 0) ..................... 325
Example SPI Master Mode (CKE = 1) ..................... 326
Example SPI Slave Mode (CKE = 0) ....................... 327
Example SPI Slave Mode (CKE = 1) ....................... 328
External Clock (All Modes Except PLL) ................... 319
Fail-Safe Clock Monitor ........................................... 246
First Start Bit Timing ................................................ 180
Full-Bridge PWM Output .......................................... 141
Half-Bridge PWM Output ......................................... 140
I2C Bus Data ............................................................ 329
I2C Bus Start/Stop Bits ............................................ 329
I2C Master Mode (7 or 10-Bit Transmission) ........... 183
I2C Master Mode (7-Bit Reception) .......................... 184
I2C Slave Mode (10-Bit Reception, SEN = 0) .......... 169
I2C Slave Mode (10-Bit Reception, SEN = 1) .......... 174
I2C Slave Mode (10-Bit Transmission) .................... 170
I2C Slave Mode (7-Bit Reception, SEN = 0) ............ 167
I2C Slave Mode (7-Bit Reception, SEN = 1) ............ 173
I2C Slave Mode (7-Bit Transmission) ...................... 168
I2C Slave Mode General Call Address
Sequence (7 or 10-Bit Address Mode) ............ 175
I2C Stop Condition Receive or Transmit Mode ........ 186
Master SSP I2C Bus Data ........................................ 331
Master SSP I2C Bus Start/Stop Bits ........................ 331
Parallel Slave Port (PSP) Read ............................... 114
Parallel Slave Port (PSP) Write ............................... 114
PWM Auto-Shutdown (PRSEN = 0,
Auto-Restart Disabled) .................................... 146
PWM Auto-Shutdown (PRSEN = 1,
Auto-Restart Enabled) ..................................... 146
PWM Direction Change ........................................... 143
PWM Direction Change at Near
100% Duty Cycle ............................................. 143
PWM Output ............................................................ 132
Repeated Start Condition ........................................ 181
Reset, Watchdog Timer (WDT), Oscillator Start-up
Timer (OST) and Power-up Timer (PWRT) ..... 322
Send Break Character Sequence ............................ 208
Slave Synchronization ............................................. 155
Slow Rise Time (MCLR Tied to VDD,
VDD Rise > TPWRT) ............................................ 45
SPI Mode (Master Mode) ......................................... 154
SPI Mode (Slave Mode, CKE = 0) ........................... 156
SPI Mode (Slave Mode, CKE = 1) ........................... 156
Synchronous Reception
(Master Mode, SREN) ..................................... 211
Synchronous Transmission ..................................... 209
Synchronous Transmission (Through TXEN) .......... 210
Time-out Sequence on Power-up
(MCLR Not Tied to VDD), Case 1 ...................... 45
Time-out Sequence on Power-up
(MCLR Not Tied to VDD), Case 2 ...................... 45
Time-out Sequence on Power-up
(MCLR Tied to VDD, VDD Rise /Tpwrt) ............... 44
Timer0 and Timer1 External Clock .......................... 323
Transition for Entry to Idle Mode ................................ 39
Transition for Entry to SEC_RUN Mode .................... 36
Transition for Entry to Sleep Mode ............................ 38
Transition for Two-Speed Start-up (INTRC) ............ 244
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
Transition for Wake From Idle to Run Mode .............. 39
Transition for Wake From Sleep ................................ 38
Transition From RC_RUN Mode to
PRI_RUN Mode ................................................. 37
Transition to RC_RUN Mode ..................................... 37
Timing Diagrams and Specifications
A/D Conversion Requirements ................................ 335
AC Characteristics
Internal RC Accuracy ....................................... 320
Capture/Compare/PWM Requirements
(Including ECCP Module) ................................ 324
CLKO and I/O Requirements ................................... 321
EUSART Synchronous Receive
Requirements .................................................. 333
EUSART Synchronous Transmission
Requirements .................................................. 333
Example SPI Mode Requirements
(CKE = 0) ................................................. 325, 327
Example SPI Mode Requirements
(CKE = 1) ......................................................... 326
Example SPI Slave Mode Requirements (CKE = 1) 328
External Clock Requirements .................................. 319
I2C Bus Data Requirements (Slave Mode) .............. 330
I2C Bus Start/Stop Bits Requirements
(Slave Mode) ................................................... 329
Master SSP I2C Bus Data Requirements ................ 332
Master SSP I2C Bus Start/Stop Bits
Requirements .................................................. 331
Parallel Slave Port Requirements ............................ 324
PLL Clock ................................................................. 320
Reset, Watchdog Timer, Oscillator Start-up
Timer, Power-up Timer and Brown-out
Reset Requirements ........................................ 322
Timer0 and Timer1 External Clock
Requirements .................................................. 323
Top-of-Stack Access .......................................................... 53
TRISE Register
PSPMODE Bit .......................................................... 107
TSTFSZ ........................................................................... 289
Two-Speed Start-up ................................................. 235, 244
Two-Word Instructions
Example Cases .......................................................... 57
TXSTA Register
BRGH Bit ................................................................. 197
© 2009 Microchip Technology Inc.
V
Voltage Reference Specifications .................................... 316
Voltage Regulator (On-Chip) ........................................... 243
W
Watchdog Timer (WDT) ........................................... 235, 242
Associated Registers ............................................... 242
Control Register ....................................................... 242
During Oscillator Failure .......................................... 245
Programming Considerations .................................. 242
WCOL ...................................................... 180, 181, 182, 185
WCOL Status Flag ................................... 180, 181, 182, 185
WWW Address ................................................................ 363
WWW, On-Line Support ...................................................... 6
X
XORLW ........................................................................... 289
XORWF ........................................................................... 290
DS39682E-page 361
PIC18F45J10 FAMILY
NOTES:
DS39682E-page 362
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
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© 2009 Microchip Technology Inc.
DS39682E-page 363
PIC18F45J10 FAMILY
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
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Device: PIC18F45J10 Family
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Literature Number: DS39682E
Questions:
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DS39682E-page 364
© 2009 Microchip Technology Inc.
PIC18F45J10 FAMILY
PIC18F45J10 FAMILY PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
X
/XX
XXX
Device
Temperature
Range
Package
Pattern
Device
PIC18F24J10/25J10, PIC18F44J10/45J10,
PIC18F24J10/25J10T(1), PIC18F44J10/45J10T(1);
VDD range 2.7V to 3.6V
PIC18LF24J10/25J10, PIC18LF44J10/45J10,
PIC18LF24J10/25J10T(1), PIC18LF44J10/45J10T(1);
VDDCORE range 2.0V to 2.7V
Temperature Range
I
=
Package
PT
SO
SP
P
ML
SS
=
=
=
=
=
=
Pattern
Examples:
a)
b)
c)
PIC18LF45J10-I/P 301 = Industrial temp.,
PDIP package, QTP pattern #301.
PIC18LF24J10-I/SO = Industrial temp., SOIC
package.
PIC18LF44J10-I/P = Industrial temp., PDIP
package.
-40°C to +85°C (Industrial)
TQFP (Thin Quad Flatpack)
SOIC
Skinny Plastic DIP
PDIP
QFN
SSOP
Note 1:
T
= in tape and reel TQFP
packages only.
QTP, SQTP, Code or Special Requirements
(blank otherwise)
© 2009 Microchip Technology Inc.
DS39682E-page 365
WORLDWIDE SALES AND SERVICE
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03/26/09
DS39682E-page 366
© 2009 Microchip Technology Inc.