MICROCHIP PIC18LF26K22-I/SO

PIC18(L)F2X/4XK22
Data Sheet
28/40/44-Pin, Low-Power,
High-Performance Microcontrollers
with nanoWatt XLP Technology
 2010 Microchip Technology Inc.
Preliminary
DS41412C
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
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
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
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
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,
PIC32 logo, rfPIC and UNI/O are registered trademarks of
Microchip Technology Incorporated in the U.S.A. and other
countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MXDEV, MXLAB, SEEVAL 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, HI-TIDE, In-Circuit Serial
Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified
logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance,
TSHARC, UniWinDriver, 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.
© 2010, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
ISBN: 978-1-60932-398-1
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.
DS41412C-page 2
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
28/40/44-Pin, Low-Power, High-Performance
Microcontrollers with nanoWatt XLP Technology
High-Performance RISC CPU:
Extreme Low-Power Management
with nanoWatt XLP:
• C Compiler Optimized Architecture:
- Optional extended instruction set designed to
optimize re-entrant code
• Up to 1024 Bytes Data EEPROM
• Up to 64 Kbytes Linear Program Memory
Addressing
• Up to 3896 Bytes Linear Data Memory Addressing
• Up to 16 MIPS Operation
• 16-bit Wide Instructions, 8-bit Wide Data Path
• Priority Levels for Interrupts
• 31-Level, Software Accessible Hardware Stack
• 8 x 8 Single-Cycle Hardware Multiplier
•
•
•
•
Special Microcontroller Features:
•
•
•
•
Flexible Oscillator Structure:
•
• Precision 16 MHz Internal Oscillator Block:
- Factory calibrated to ± 1%
- Selectable frequencies, 31 kHz to 16 MHz
- 64 MHz performance available using PLL –
no external components required
• Four Crystal modes up to 64 MHz
• Two External Clock modes up to 64 MHz
• 4X Phase Lock Loop (PLL)
• Secondary Oscillator using Timer1 @ 32 kHz
• Fail-Safe Clock Monitor:
- Allows for safe shutdown if peripheral clock
stops
- Two-Speed Oscillator Start-up
•
•
•
Full 5.5V Operation – PIC18FXXK22 devices
1.8V to 3.6V Operation – PIC18LFXXK22 devices
Self-Programmable under Software Control
High/Low-Voltage Detection (HLVD) module:
- Programmable 16-Level
- Interrupt on High/Low-Voltage Detection
Programmable Brown-out Reset (BOR):
- With software enable option
- Configurable shutdown in Sleep
Extended Watchdog Timer (WDT):
- Programmable period from 4 ms to 131s
In-Circuit Serial Programming™ (ICSP™):
- Single-Supply 3V
In-Circuit Debug (ICD)
Peripheral Highlights:
Analog Features:
• Analog-to-Digital Converter (ADC) module:
- 10-bit resolution, up to 30 external channels
- Auto-acquisition capability
- Conversion available during Sleep
- Fixed Voltage Reference (FVR) channel
- Independent input multiplexing
• Analog Comparator module:
- Two rail-to-rail analog comparators
- Independent input multiplexing
• Digital-to-Analog Converter (DAC) module:
- Fixed Voltage Reference (FVR) with 1.024V,
2.048V and 4.096V output levels
- 5-bit rail-to-rail resistive DAC with positive
and negative reference selection
• Charge Time Measurement Unit (CTMU) module:
- Supports capacitive touch sensing for touch
screens and capacitive switches
 2010 Microchip Technology Inc.
Sleep mode: 20 nA, typical
Watchdog Timer: 300 nA, typical
Timer1 Oscillator: 800 nA @ 32 kHz
Peripheral Module Disable
• Up to 35 I/O Pins plus 1 Input-Only Pin:
- High-Current Sink/Source 25 mA/25 mA
- Three programmable external interrupts
- Four programmable interrupt-on-change
- Nine programmable weak pull-ups
- Programmable slew rate
• SR Latch:
- Multiple Set/Reset input options
• Two Capture/Compare/PWM (CCP) modules
• Three Enhanced CCP (ECCP) modules:
- One, two or four PWM outputs
- Selectable polarity
- Programmable dead time
- Auto-Shutdown and Auto-Restart
- PWM steering
• Two Master Synchronous Serial Port (MSSP)
modules:
- 3-wire SPI (supports all 4 modes)
- I2C™ Master and Slave modes with address
mask
Preliminary
DS41412C-page 3
PIC18(L)F2X/4XK22
• Two Enhanced Universal Synchronous
Asynchronous Receiver Transmitter (EUSART)
modules:
- Supports RS-485, RS-232 and LIN
- RS-232 operation using internal oscillator
- Auto-Wake-up on Break
- Auto-Baud Detect
SRAM
(Bytes)
EEPROM
(Bytes)
I/O(1)
10-bit
A/D Channels(2)
CCP
ECCP
(Full-Bridge)
ECCP
(Half-Bridge)
SPI
I2C™
EUSART
Comparator
CTMU
BOR/LVD
SR Latch
8-bit Timer
16-bit Timer
MSSP
# Single-Word
Instructions
Data Memory
Flash
(Bytes)
Program
Memory
PIC18(L)F23K22
8K
4096
512
256
25
19
2
1
2
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F24K22
16K
8192
768
256
25
19
2
1
2
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F25K22
32K
16384
1536
256
25
19
2
1
2
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F26K22
64k
32768
3896
1024
25
19
2
1
2
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F43K22
8K
4096
512
256
36
30
2
2
1
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F44K22
16K
8192
768
256
36
30
2
2
1
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F45K22
32K
16384
1536
256
36
30
2
2
1
2
2
2
2
Y
Y
Y
3
4
PIC18(L)F46K22
64k
32768
3896
1024
36
30
2
2
1
2
2
2
2
Y
Y
Y
3
4
Device
Note 1:
2:
One pin is input only.
Channel count includes internal FVR and DAC channels.
DS41412C-page 4
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Pin Diagrams
28-pin PDIP, SOIC, SSOP
28
27
26
25
24
23
22
21
20
19
18
17
16
15
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
VDD
VSS
RC7
RC6
RC5
RC4
RA1
RA0
MCLR/VPP/RE3
RB7
RB6
RB5
RB4
28-pin QFN, UQFN(1)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
PIC18(L)F2XK22
MCLR/VPP/RE3
RA0
RA1
RA2
RA3
RA4
RA5
VSS
RA7
RA6
RC0
RC1
RC2
RC3
28 27 26 25 24 23 22
1
2
3
4 PIC18(L)F2XK22
5
6
7
8 9 10 11 12 13 14
21
20
19
18
17
16
15
RB3
RB2
RB1
RB0
VDD
VSS
RC7
RC0
RC1
RC2
RC3
RC4
RC5
RC6
RA2
RA3
RA4
RA5/
VSS
RA7
RA6
Note
1:
The 28-pin UQFN package is available only for PIC18(L)F23K22 and PIC18(L)F24K22.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 5
PIC18(L)F2X/4XK22
Pin Diagrams
40-pin PDIP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
PIC18(L)F4XK22
MCLR/VPP/RE3
RA0
RA1
RA2
RA3
RA4
RA5
RE0
RE1
RE2
VDD
VSS
RA7
RA6
RC0
RC1
RC2
RC3
RD0
RD1
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
VDD
VSS
RD7
RD6
RD5
RD4
RC7
RC6
RC5
RC4
RD3
RD2
40
39
38
37
36
35
34
33
32
31
RC6
RC5
RC4
RD3
RD2
RD1
RD0
RC3
RC2
RC1
40-pin UQFN
1
2
3
4
5 PIC18(L)F4XK22
6
7
8
9
10
30
29
28
27
26
25
24
23
22
21
RC0
RA6
RA7
VSS
VDD
RE2
RE1
RE0
RA5
RA4
RB3
RB4
RB5
RB6
RB7
MCLR/VPP/RE3
RA0
RA1
RA2
RA3
11
12
13
14
15
16
17
18
19
20
RC7
RD4
RD5
RD6
RD7
VSS
VDD
RB0
RB1
RB2
DS41412C-page 6
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Pin Diagrams (Cont.’d)
1
2
3
4
5
6 PIC18(L)F4XK22
7
8
9
10
11
NC
RC0
RA6
RA7
VSS
VDD
RE2
RE1
RE0
RA5
RA4
33
32
31
30
29
28
27
26
25
24
23
NC
NC
RB4
RB5
RB6
RB7
MCLR/VPP/RE3
RA0
RA1
RA2
RA3
22
21
20
19
18
17
16
15
14
13
12
RC7
RD4
RD5
RD6
RD7
VSS
VDD
RB0
RB1
RB2
RB3
44
43
42
41
40
39
38
37
36
35
34
RC6
RC5
RC4
RD3
RD2
RD1
RD0
RC3
RC2
RC1
NC
44-pin TQFP
1
2
3
4
5
6 PIC18(L)F4XK22
7
8
9
10
11
33
32
31
30
29
28
27
26
25
24
23
RA6
RA7
VSS
VSS
VDD
VDD
RE2
RE1
RE0
RA5
RA4
RB3
NC
RB4
RB5
RB6
RB7
MCLR/VPP/RE3
RA0
RA1
RA2
RA3
22
21
20
19
18
17
16
15
14
13
12
RC7
RD4
RD5
RD6
RD7
VSS
VDD
VDD
RB0
RB1
RB2
44
43
42
41
40
39
38
37
36
35
34
RC6
RC5
RC4
RD3
RD2
RD1
RD0
RC3
RC2
RC1
RC0
44-pin QFN
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 7
PIC18(L)F2X/4XK22
C2IN+
AN3
5
2
RA3
6
3
RA4
AN4
Basic
AN2
Pull-up
RA2
Interrupts
1
Timers
C12IN1-
4
MSSP
C12IN0-
AN1
EUSART
AN0
RA1
(E)CCP
RA0
28
Reference
Comparator
27
3
SR Latch
Analog
2
CTMU
I/O
PIC18(L)F2XK22 PIN SUMMARY
28-QFN, UQFN
28-SSOP, SOIC
28-SPDIP
TABLE 1:
VREF-/
DACOUT
C1IN+
VREF+
C1OUT
SRQ
C2OUT
SRNQ
CCP5
T0CKI
7
4
RA5
10
7
RA6
OSC2/
CLKO
9
6
RA7
OSC1/
CLKI
21
18
RB0
AN12
22
19
RB1
AN10
23
20
RB2
AN8
24
21
RB3
AN9
SRI
SS1
CCP4
FLT0
SS2
INT0
Y
P1C
SCK2/
SCL2
INT1
Y
CTED1
P1B
SDI2/
SDA
INT2
Y
CTED2
CCP2/
P2A(1)
SDO2
C12IN3-
C12IN2-
HLVDIN
Y
25
22
RB4
AN11
P1D
T5G
IOC
Y
26
23
RB5
AN13
CCP3/
P3A(4)
P2B(3)
T1G
T3CKI(2)
IOC
Y
27
24
RB6
TX2/CK2
IOC
Y
PGC
28
25
RB7
RX2/DT2
IOC
Y
PGD
11
8
RC0
P2B(3)
SOSCO/
T1CKI
T3CKI(2)
T3G
12
9
RC1
CCP2/
P2A(1)
SOSCI
13
10
RC2
AN14
CCP1/
P1A
T5CKI
14
11
RC3
AN15
SCK1/
SCL1
15
12
RC4
AN16
SDI1/
SDA1
CTPLS
16
13
RC5
AN17
17
14
RC6
AN18
CCP3/
P3A(4)
TX1/CK1
SDO1
18
15
RC7
AN19
P3B
RX1/DT1
1
26
RE3
MCLR/
VPP
8
5
VSS
19
16
VSS
20
17
Note 1:
2:
3:
4:
VDD
CCP2/P2A multiplexed in fuses.
T3CKI multiplexed in fuses.
P2B multiplexed in fuses.
CCP3/P3A multiplexed in fuses.
DS41412C-page 8
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
21
21
RA2
AN2
C2IN+
AN3
Basic
19
Pull-up
C12IN1-
4
Interrupts
C12IN0-
AN1
Timers
AN0
RA1
MSSP
Comparator
RA0
20
EUSART
Analog
19
20
(E)CCP
I/O
19
18
Reference
44-QFN
17
3
SR Latch
44-TQFP
2
CTMU
40-UQFN
PIC18(L)F4XK22 PIN SUMMARY
40-PDIP
TABLE 2:
VREFDACOUT
5
20
22
22
RA3
6
21
23
23
RA4
7
22
24
24
RA5
14
29
31
33
RA6
OSC2/
CLKO
13
28
30
32
RA7
OSC1/
CLKI
AN4
C1IN+
VREF+
C1OUT
SRQ
C2OUT
SRN
Q
T0CKI
HLVDIN
SRI
SS1
33
8
8
9
RB0
AN12
34
9
9
10
RB1
AN10
FLT0
INT0
35
10
10
11
RB2
AN8
36
11
11
12
RB3
AN9
37
12
14
14
RB4
AN11
38
13
15
15
RB5
AN13
39
14
16
16
RB6
IOC
Y
PGC
40
15
17
17
RB7
IOC
Y
PGD
15
30
32
34
RC0
P2B(4)
SOSCO/
T1CKI
T3CKI(2)
T3G
16
31
35
35
RC1
CCP2(1)
P2A
SOSCI
17
32
36
36
RC2
AN14
CCP1/
P1A
T5CKI
18
33
37
37
RC3
AN15
SCK1/
SCL1
23
38
42
42
RC4
AN16
SDI1/
SDA1
C12IN3CTED1
C12IN2-
CTED2
Y
Y
24
39
43
43
RC5
AN17
25
40
44
44
RC6
AN18
TX1/
CK1
26
1
1
1
RC7
AN19
RX1/
DT1
19
34
38
38
RD0
AN20
20
35
39
39
RD1
AN21
CCP4
21
36
40
40
RD2
AN22
P2B(4)
22
37
41
41
RD3
AN23
P2C
SS2
27
2
2
2
RD4
AN24
P2D
SD02
T5G
IOC
Y
T1G
T3CKI(2)
IOC
Y
SDO1
SCK2/
SCL2
SDI2/
SDA2
28
3
3
3
RD5
AN25
P1B
29
4
4
4
RD6
AN26
P1C
TX2
CK2
30
5
5
5
RD7
AN27
P1D
RX2/
DT2
8
23
25
25
RE0
AN5
CCP3/
P3A(3)
Note 1:
2:
3:
4:
Y
INT2
CCP2/
P2A(1)
CCP3/
P3A(3)
CTPLS
Y
INT1
CCP2 multiplexed in fuses.
T3CKI multiplexed in fuses.
CCP3/P3A multiplexed in fuses.
P2B multiplexed in fuses.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 9
PIC18(L)F2X/4XK22
Interrupts
P3B
10
25
27
27
RE2
AN7
CCP5
1
16
18
18
RE3
11
32
7, 26
7
28
7,8
28, 29
VDD
12
31
6, 27
6
29
6
30, 31
VSS
—
—
12, 13
33, 34
13
Note 1:
2:
3:
4:
Basic
AN6
Pull-up
RE1
Timers
26
MSSP
26
EUSART
Analog
24
(E)CCP
I/O
Reference
44-QFN
SR Latch
44-TQFP
9
CTMU
40-UQFN
Comparator
PIC18(L)F4XK22 PIN SUMMARY (CONTINUED)
40-PDIP
TABLE 2:
Y
MCLR/
VPP
NC
CCP2 multiplexed in fuses.
T3CKI multiplexed in fuses.
CCP3/P3A multiplexed in fuses.
P2B multiplexed in fuses.
DS41412C-page 10
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Table of Contents
1.0 Device Overview ....................................................................................................................................................................... 13
2.0 Oscillator Module (With Fail-Safe Clock Monitor)...................................................................................................................... 27
3.0 Power-Managed Modes ............................................................................................................................................................ 47
4.0 Reset ......................................................................................................................................................................................... 59
5.0 Memory Organization ................................................................................................................................................................ 69
6.0 Flash Program Memory............................................................................................................................................................. 95
7.0 Data EEPROM Memory .......................................................................................................................................................... 105
8.0 8 x 8 Hardware Multiplier......................................................................................................................................................... 111
9.0 Interrupts ................................................................................................................................................................................. 113
10.0 I/O Ports .................................................................................................................................................................................. 133
11.0 Timer0 Module ........................................................................................................................................................................ 157
12.0 Timer1/3/5 Module with Gate Control...................................................................................................................................... 161
13.0 Timer2/4/6 Module .................................................................................................................................................................. 173
14.0 Capture/Compare/PWM Modules ........................................................................................................................................... 177
15.0 Master Synchronous Serial Port (MSSP1 and MSSP2) Module ............................................................................................. 207
16.0 Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) .............................................................. 263
17.0 Analog-to-Digital Converter (ADC) Module ............................................................................................................................. 291
18.0 Comparator Module................................................................................................................................................................. 305
19.0 Charge Time Measurement Unit (CTMU) ............................................................................................................................... 317
20.0 SR Latch.................................................................................................................................................................................. 333
21.0 Fixed Voltage Reference (FVR) .............................................................................................................................................. 337
22.0 Digital-to-Analog Converter (DAC) .......................................................................................................................................... 339
23.0 High/Low-Voltage Detect (HLVD)............................................................................................................................................ 343
24.0 Special Features of the CPU................................................................................................................................................... 349
25.0 Instruction Set Summary ......................................................................................................................................................... 367
26.0 Development Support.............................................................................................................................................................. 417
27.0 Electrical Characteristics ......................................................................................................................................................... 421
28.0 DC and AC Characteristics Graphs and Tables...................................................................................................................... 461
29.0 Packaging Information............................................................................................................................................................. 463
Appendix A: Revision History............................................................................................................................................................ 481
Appendix B: Device Differences ....................................................................................................................................................... 482
Index ................................................................................................................................................................................................. 483
The Microchip Web Site .................................................................................................................................................................... 493
Customer Change Notification Service ............................................................................................................................................. 493
Customer Support ............................................................................................................................................................................. 493
Reader Response ............................................................................................................................................................................. 494
Product Identification System ........................................................................................................................................................... 495
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 11
PIC18(L)F2X/4XK22
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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To determine if an errata sheet exists for a particular device, please check with one of the following:
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DS41412C-page 12
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
1.0
DEVICE OVERVIEW
1.1.2
This document contains device specific information for
the following devices:
• PIC18F23K22
• PIC18LF23K22
• PIC18F24K22
• PIC18LF24K22
• PIC18F25K22
• PIC18LF25K22
• PIC18F26K22
• PIC18LF26K22
• PIC18F43K22
• PIC18LF43K22
• PIC18F44K22
• PIC18LF44K22
• PIC18F45K22
• PIC18LF45K22
• PIC18F46K22
• PIC18LF46K22
This family offers the advantages of all PIC18
microcontrollers – namely, high computational
performance at an economical price – with the addition
of high-endurance, Flash program memory. On top of
these features, the PIC18(L)F2X/4XK22 family
introduces design enhancements that make these
microcontrollers a logical choice for many highperformance, power sensitive applications.
1.1
1.1.1
New Core Features
nanoWatt TECHNOLOGY
All of the devices in the PIC18(L)F2X/4XK22 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 powersaving 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 27.0 “Electrical Characteristics”
for values.
 2010 Microchip Technology Inc.
MULTIPLE OSCILLATOR OPTIONS
AND FEATURES
All of the devices in the PIC18(L)F2X/4XK22 family
offer ten different oscillator options, allowing users a
wide range of choices in developing application
hardware. These include:
• Four Crystal modes, using crystals or ceramic
resonators
• Two External Clock modes, offering the option of
using two pins (oscillator input and a divide-by-4
clock output) or one pin (oscillator input, with the
second pin reassigned as general I/O)
• Two External RC Oscillator modes with the same
pin options as the External Clock modes
• An internal oscillator block which contains a
16 MHz HFINTOSC oscillator and a 31 kHz
LFINTOSC oscillator, which together provide 8
user selectable clock frequencies, from 31 kHz to
16 MHz. This option frees the two oscillator pins
for use as additional general purpose I/O.
• A Phase Lock Loop (PLL) frequency multiplier,
available to both external and internal oscillator
modes, which allows clock speeds of up to
64 MHz. Used with the internal oscillator, the PLL
gives users a complete selection of clock speeds,
from 31 kHz to 64 MHz – all without using an
external crystal or clock circuit.
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 LFINTOSC. If a
clock failure occurs, the controller is switched to
the internal oscillator block, allowing for continued
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.
Preliminary
DS41412C-page 13
PIC18(L)F2X/4XK22
1.2
Other Special Features
1.3
• Memory Endurance: The Flash cells for both
program memory and data EEPROM are rated to
last for many thousands of erase/write cycles – up to
10K for program memory and 100K for EEPROM.
Data retention without refresh is conservatively
estimated to be greater than 40 years.
• Self-programmability: These devices can write
to their own program memory spaces under internal software control. By using a bootloader routine
located in the protected Boot Block at the top of
program memory, it becomes possible to create
an application that can update itself in the field.
• Extended Instruction Set: The PIC18(L)F2X/
4XK22 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
- Auto-Restart, to reactivate outputs once the
condition has cleared
- Output steering to selectively enable one or
more of 4 outputs to provide the PWM signal.
• Enhanced Addressable EUSART: This serial
communication module is capable of standard
RS-232 operation and provides support for the LIN
bus protocol. Other enhancements include
automatic baud rate detection and a 16-bit Baud
Rate Generator for improved resolution. When the
microcontroller is using the internal oscillator
block, the EUSART provides stable operation for
applications that talk to the outside world without
using an external crystal (or its accompanying
power requirement).
• 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
postscaler, allowing an extended time-out range
that is stable across operating voltage and
temperature. See Section 27.0 “Electrical
Characteristics” for time-out periods.
• Charge Time Measurement Unit (CTMU)
• SR Latch Output:
DS41412C-page 14
Details on Individual Family
Members
Devices in the PIC18(L)F2X/4XK22 family are available in 28-pin and 40/44-pin packages. The block diagram for the device family is shown in Figure 1-1.
The devices have the following differences:
1.
2.
3.
4.
5.
6.
7.
Flash program memory
Data Memory SRAM
Data Memory EEPROM
A/D channels
I/O ports
ECCP modules (Full/Half Bridge)
Input Voltage Range/Power Consumption
All other features for devices in this family are identical.
These are summarized in Table 1-1.
The pinouts for all devices are listed in the pin summary
tables: Table 1 and Table 2, and I/O description tables:
Table 1-2 and Table 1-3.
Preliminary
 2010 Microchip Technology Inc.
A, B, C, E(1)
A, B, C, E(1)
Data EEPROM Memory (Bytes)
 2010 Microchip Technology Inc.
1
2 internal
17 input
Enhanced CCP Modules (ECCP)
- Full Bridge
10-bit Analog-to-Digital Module
(ADC)
Preliminary
Yes
Yes
Yes
Programmable
High/Low-Voltage Detect (HLVD)
Programmable Brown-out Reset
(BOR)
Note
1:
PORTE contains the single RE3 read-only bit.
Operating Frequency
Instruction Set
DC - 64 MHz
75 Instructions;
83 with Extended Instruction Set enabled
POR, BOR,
RESET Instruction,
Stack Overflow,
Stack Underflow
(PWRT, OST),
MCLR, WDT
Yes
Charge Time Measurement Unit
Module (CTMU)
Resets (and Delays)
40-pin PDIP
40-pin UQFN
44-pin QFN
44-pin TQFP
2 internal
28 input
2
1
2
A, B, C, D, E
256
512
4096
8192
PIC18F43K22
PIC18LF43K22
2 MSSP,
2 EUSART
SR Latch
Serial Communications
4
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
2 internal
17 input
1
2
2
A, B, C, E(1)
33
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
2 internal
17 input
1
2
2
3896
1024
Timers (16-bit)
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
28-pin UQFN
2 internal
17 input
1
2
2
A, B, C, E(1)
256
1536
32768
65536
PIC18F26K22
PIC18LF26K22
Interrupt Sources
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
28-pin UQFN
2
Enhanced CCP Modules (ECCP)
- Half Bridge
Packages
2
Capture/Compare/PWM Modules (CCP)
768
16384
32768
PIC18F25K22
PIC18LF25K22
40-pin PDIP
40-pin UQFN
44-pin QFN
44-pin TQFP
2 internal
28 input
2
1
2
A, B, C, D, E
256
768
8192
16384
PIC18F44K22
PIC18LF44K22
40-pin PDIP
40-pin UQFN
44-pin QFN
44-pin TQFP
2 internal
28 input
2
1
2
A, B, C, D, E
256
1536
16384
32768
PIC18F45K22
PIC18LF45K22
40-pin PDIP
40-pin UQFN
44-pin QFN
44-pin TQFP
2 internal
28 input
2
1
2
A, B, C, D, E
1024
3896
32768
65536
PIC18F46K22
PIC18LF46K22
TABLE 1-1:
I/O Ports
256
512
256
Data Memory (Bytes)
8192
4096
16384
8192
PIC18F24K22
PIC18LF24K22
Program Memory
(Instructions)
PIC18F23K22
PIC18LF23K22
Program Memory (Bytes)
Features
PIC18(L)F2X/4XK22
DEVICE FEATURES
DS41412C-page 15
PIC18(L)F2X/4XK22
FIGURE 1-1:
PIC18(L)F2X/4XK22 FAMILY BLOCK DIAGRAM
Data Bus<8>
Table Pointer<21>
Data Latch
8
8
inc/dec logic
Data Memory
PCLATU PCLATH
21
PORTA
Address Latch
20
PCU PCH PCL
Program Counter
RA0:RA7
12
Data Address<12>
31-Level Stack
4
BSR
Address Latch
Program Memory
(8/16/32/64 Kbytes)
STKPTR
12
FSR0
FSR1
FSR2
Data Latch
8
PORTB
12
RB0:RB7
inc/dec
logic
Table Latch
Instruction Bus <16>
4
Access
Bank
Address
Decode
ROM Latch
PORTC
RC0:RC7
IR
Instruction
Decode and
Control
8
State machine
control signals
PRODH PRODL
PORTD
8 x 8 Multiply
3
8
W
BITOP
8
Internal
Oscillator
Block
OSC1(2)
(2)
OSC2
LFINTOSC
Oscillator
SOSCI
16 MHz
Oscillator
SOSCO
Single-Supply
Programming
In-Circuit
Debugger
MCLR(1)
BOR
HLVD
FVR
DAC
Note
Comparators
C1/C2
Data
EEPROM
ECCP1
ECCP2(3)
ECCP3
Power-up
Timer
8
8
8
8
Oscillator
Start-up Timer
Power-on
Reset
PORTE
ALU<8>
RE0:RE2
RE3(1)
8
Watchdog
Timer
Precision
Band Gap
Reference
Brown-out
Reset
Fail-Safe
Clock Monitor
RD0:RD7
FVR
Timer0
Timer1
Timer3
Timer5
Timer2
Timer4
Timer6
CTMU
DAC
CCP4
CCP5
MSSP1
MSSP2
EUSART1
EUSART2
SR Latch
ADC
10-bit
FVR
1:
RE3 is only available when MCLR functionality is disabled.
2:
OSC1/CLKIN and OSC2/CLKOUT are only available in select oscillator modes and when these pins are not being used as digital I/O.
Refer to Section 2.0 “Oscillator Module (With Fail-Safe Clock Monitor)” for additional information.
3:
Full-Bridge operation for PIC18(L)F4XK22, Half-Bridge operation for PIC18(L)F2XK22.
DS41412C-page 16
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 1-2:
PIC18(L)F2XK22 PINOUT I/O DESCRIPTIONS
Pin Number
PDIP,
SOIC
QFN,
UQFN
2
27
3
28
4
1
5
2
6
3
7
4
10
7
Legend:
Note 1:
2:
Pin
Type
Pin Name
Buffer
Type
Description
RA0/C12IN0-/AN0
RA0
I/O
TTL
C12IN0-
I
Analog
Comparators C1 and C2 inverting input.
Digital I/O.
AN0
I
Analog
Analog input 0.
RA1/C12IN1-/AN1
RA1
I/O
TTL
C12IN1-
I
Analog
Comparators C1 and C2 inverting input.
Digital I/O.
AN1
I
Analog
Analog input 1.
RA2/C2IN+/AN2/DACOUT/VREFRA2
I/O
TTL
C2IN+
I
Analog
Digital I/O.
Comparator C2 non-inverting input.
AN2
I
Analog
Analog input 2.
DACOUT
O
Analog
DAC Reference output.
VREF-
I
Analog
A/D reference voltage (low) input.
RA3/C1IN+/AN3/VREF+
RA3
I/O
TTL
C1IN+
I
Analog
Digital I/O.
Comparator C1 non-inverting input.
AN3
I
Analog
Analog input 3.
VREF+
I
Analog
A/D reference voltage (high) input.
RA4
I/O
TTL
RA4/CCP5/C1OUT/SRQ/T0CKI
Digital I/O.
CCP5
I/O
ST
C1OUT
O
CMOS
Capture 5 input/Compare 5 output/PWM 5 output.
SRQ
O
TTL
SR Latch Q output.
T0CKI
I
ST
Timer0 external clock input.
Digital I/O.
Comparator C1 output.
RA5/C2OUT/SRNQ/SS1/HLVDIN/AN4
RA5
I/O
TTL
C2OUT
O
CMOS
SRNQ
O
TTL
SR Latch Q output.
Comparator C2 output.
SS1
I
TTL
SPI slave select input (MSSP1).
HLVDIN
I
Analog
High/Low-Voltage Detect input.
AN4
I
Analog
Analog input 4.
TTL
RA6/CLKO/OSC2
RA6
I/O
CLKO
O
Digital I/O.
In RC mode, OSC2 pin outputs CLKOUT which has
1/4 the frequency of OSC1 and denotes the instruction
cycle rate.
OSC2
O
Oscillator crystal output. Connects to crystal or resonator
in Crystal Oscillator mode.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 17
PIC18(L)F2X/4XK22
TABLE 1-2:
PIC18(L)F2XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP,
SOIC
QFN,
UQFN
9
6
21
18
22
19
23
20
24
21
Legend:
Note 1:
2:
Pin
Type
Pin Name
Buffer
Type
Description
RA7/CLKI/OSC1
RA7
I/O
TTL
CLKI
I
CMOS
External clock source input. Always associated with pin
function OSC1.
Digital I/O.
OSC1
I
ST
Oscillator crystal input or external clock source input ST
buffer when configured in RC mode; CMOS otherwise.
RB0/INT0/CCP4/FLT0/SRI/SS2/AN12
RB0
I/O
TTL
Digital I/O.
INT0
I
ST
External interrupt 0.
CCP4
I/O
ST
Capture 4 input/Compare 4 output/PWM 4 output.
FLT0
I
ST
PWM Fault input for ECCP Auto-Shutdown.
SRI
I
ST
SR Latch input.
SS2
I
TTL
SPI slave select input (MSSP2).
AN12
I
Analog
Analog input 12.
RB1/INT1/P1C/SCK2/SCL2/C12IN3-/AN10
RB1
I/O
TTL
Digital I/O.
INT1
I
ST
External interrupt 1.
P1C
O
CMOS
SCK2
I/O
ST
Synchronous serial clock input/output for SPI mode
(MSSP2).
SCL2
I/O
ST
Synchronous serial clock input/output for I2C™ mode
(MSSP2).
C12IN3-
I
Analog
Comparators C1 and C2 inverting input.
AN10
I
Analog
Analog input 10.
Enhanced CCP1 PWM output.
RB2/INT2/CTED1/P1B/SDI2/SDA2/AN8
RB2
I/O
TTL
Digital I/O.
INT2
I
ST
External interrupt 2.
CTED1
I
ST
CTMU Edge 1 input.
P1B
O
CMOS
SDI2
I
ST
SPI data in (MSSP2).
Enhanced CCP1 PWM output.
SDA2
I/O
ST
I2C™ data I/O (MSSP2).
AN8
I
Analog
Analog input 8.
RB3/CTED2/P2A/CCP2/SDO2/C12IN2-/AN9
RB3
I/O
TTL
CTED2
I
ST
Digital I/O.
P2A
O
CMOS
CCP2(2)
I/O
ST
Capture 2 input/Compare 2 output/PWM 2 output.
SDO2
O
—
SPI data out (MSSP2).
C12IN2-
I
Analog
Comparators C1 and C2 inverting input.
AN9
I
Analog
Analog input 9.
CTMU Edge 2 input.
Enhanced CCP2 PWM output.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
DS41412C-page 18
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 1-2:
PIC18(L)F2XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP,
SOIC
QFN,
UQFN
25
22
26
23
Pin Name
24
28
25
11
8
12
9
Note 1:
2:
Description
RB4
I/O
TTL
Digital I/O.
IOC0
I
TTL
Interrupt-on-change pin.
P1D
O
CMOS
T5G
I
ST
AN11
I
Analog
Enhanced CCP1 PWM output.
Timer5 external clock gate input.
Analog input 11.
RB5/IOC1/P2B/P3A/CCP3/T3CKI/T1G/AN13
I/O
TTL
Digital I/O.
Interrupt-on-change pin.
IOC1
I
TTL
P2B(1)
O
CMOS
P3A(1)
O
CMOS
CCP3(1)
I/O
ST
Capture 3 input/Compare 3 output/PWM 3 output.
T3CKI(2)
I
ST
Timer3 clock input.
T1G
I
ST
AN13
I
Analog
Enhanced CCP2 PWM output.
Enhanced CCP3 PWM output.
Timer1 external clock gate input.
Analog input 13.
RB6/IOC2/TX2/CK2/PGC
RB6
I/O
TTL
Digital I/O.
IOC2
I
TTL
Interrupt-on-change pin.
TX2
O
—
EUSART 2 asynchronous transmit.
CK2
I/O
ST
EUSART 2 synchronous clock (see related RXx/DTx).
PGC
I/O
ST
In-Circuit Debugger and ICSP™ programming clock pin.
RB7/IOC3/RX2/DT2/PGD
RB7
I/O
TTL
Digital I/O.
IOC3
I
TTL
Interrupt-on-change pin.
RX2
I
ST
EUSART 2 asynchronous receive.
DT2
I/O
ST
EUSART 2 synchronous data (see related TXx/CKx).
PGD
I/O
ST
In-Circuit Debugger and ICSP™ programming data pin.
Digital I/O.
RC0/P2B/T3CKI/T3G/T1CKI/SOSCO
RC0
I/O
TTL
P2B(2)
O
CMOS
T3CKI(1)
I
ST
Timer3 clock input.
T3G
I
ST
Timer3 external clock gate input.
T1CKI
I
ST
Timer1 clock input.
SOSCO
O
—
Secondary oscillator output.
I/O
TTL
Enhanced CCP1 PWM output.
RC1/P2A/CCP2/SOSCI
RC1
Legend:
Buffer
Type
RB4/IOC0/P1D/T5G/AN11
RB5
27
Pin
Type
P2A
O
CMOS
CCP2(1)
I/O
ST
SOSCI
I
Analog
Digital I/O.
Enhanced CCP2 PWM output.
Capture 2 input/Compare 2 output/PWM 2 output.
Secondary oscillator input.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 19
PIC18(L)F2X/4XK22
TABLE 1-2:
PIC18(L)F2XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP,
SOIC
QFN,
UQFN
Pin Name
13
10
RC2/CTPLS/P1A/CCP1/T5CKI/AN14
14
11
15
12
16
13
17
14
15
1
26
Legend:
Note 1:
2:
Buffer
Type
Description
RC2
I/O
TTL
CTPLS
O
—
CTMU pulse generator output.
P1A
O
CMOS
Enhanced CCP1 PWM output.
Digital I/O.
CCP1
I/O
ST
Capture 1 input/Compare 1 output/PWM 1 output.
T5CKI
I
ST
Timer5 clock input.
AN14
I
Analog
Analog input 14.
RC3/SCK1/SCL1/AN15
RC3
I/O
TTL
Digital I/O.
SCK1
I/O
ST
Synchronous serial clock input/output for SPI mode
(MSSP2).
SCL1
I/O
ST
Synchronous serial clock input/output for I2C™ mode
(MSSP2).
AN15
I
Analog
Analog input 15.
RC4/SDI1/SDA1/AN16
RC4
I/O
TTL
Digital I/O.
SDI1
I
ST
SPI data in (MSSP1).
SDA1
I/O
ST
I2C™ data I/O (MSSP1).
AN16
I
Analog
Analog input 16.
RC5/SDO1/AN17
RC5
I/O
TTL
SDO1
O
—
AN17
I
Analog
Digital I/O.
SPI data out (MSSP1).
Analog input 17.
RC6/P3A/CCP3/TX1/CK1/AN18
RC6
I/O
TTL
P3A(2)
O
CMOS
CCP3
18
Pin
Type
(2)
Digital I/O.
Enhanced CCP3 PWM output.
I/O
ST
Capture 3 input/Compare 3 output/PWM 3 output.
TX1
O
—
EUSART 1 asynchronous transmit.
CK1
I/O
ST
EUSART 1 synchronous clock (see related RXx/DTx).
AN18
I
Analog
Analog input 18.
RC7/P3B/RX1/DT1/AN19
RC7
I/O
TTL
P3B
O
CMOS
Digital I/O.
RX1
I
ST
EUSART 1 asynchronous receive.
DT1
I/O
ST
EUSART 1 synchronous data (see related TXx/CKx).
AN19
I
Analog
RE3
I
ST
VPP
P
MCLR
I
Enhanced CCP3 PWM output.
Analog input 19.
RE3/VPP/MCLR
Digital input.
Programming voltage input.
ST
Active-Low Master Clear (device Reset) input.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
DS41412C-page 20
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 1-2:
PIC18(L)F2XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
QFN,
UQFN
Pin Name
Pin
Type
Buffer
Type
20
17
VDD
P
—
Positive supply for logic and I/O pins.
8, 19
5, 16
VSS
P
—
Ground reference for logic and I/O pins.
PDIP,
SOIC
Legend:
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Note 1:
2:
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS
Pin Number
PDIP
TQFP
QFN
UQFN
2
19
19
17
3
4
5
6
20
21
22
23
Legend:
Note
Description
20
21
22
23
18
19
20
21
Pin
Type
Pin Name
Buffer
Type
Description
RA0/C12IN0-/AN0
RA0
I/O
C12IN0-
I
Analog Comparators C1 and C2 inverting input.
TTL
Digital I/O.
AN0
I
Analog Analog input 0.
RA1/C12IN1-/AN1
RA1
I/O
C12IN1-
I
Analog Comparators C1 and C2 inverting input.
TTL
Digital I/O.
AN1
I
Analog Analog input 1.
RA2/C2IN+/AN2/DACOUT/VREFRA2
I/O
C2IN+
I
TTL
Digital I/O.
Analog Comparator C2 non-inverting input.
AN2
I
Analog Analog input 2.
DACOUT
O
Analog DAC Reference output.
VREF-
I
Analog A/D reference voltage (low) input.
RA3/C1IN+/AN3/VREF+
RA3
I/O
C1IN+
I
TTL
Digital I/O.
Analog Comparator C1 non-inverting input.
AN3
I
Analog Analog input 3.
VREF+
I
Analog A/D reference voltage (high) input.
RA4/C1OUT/SRQ/T0CKI
RA4
I/O
C1OUT
O
TTL
Digital I/O.
SRQ
O
TTL
SR Latch Q output.
T0CKI
I
ST
Timer0 external clock input.
CMOS Comparator C1 output.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 21
PIC18(L)F2X/4XK22
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
TQFP
QFN
UQFN
7
24
24
22
14
13
33
34
35
36
31
30
32
8
9
9
10
10
11
Legend:
Note
33
11
12
29
28
8
9
10
11
Pin
Type
Pin Name
Buffer
Type
Description
RA5/C2OUT/SRNQ/SS1/HLVDIN/AN4
RA5
I/O
TTL
Digital I/O.
C2OUT
O
SRNQ
O
TTL
SR Latch Q output.
SS1
I
TTL
SPI slave select input (MSSP1).
HLVDIN
I
Analog High/Low-Voltage Detect input.
AN4
I
Analog Analog input 4.
CMOS Comparator C2 output.
RA6/CLKO/OSC2
RA6
I/O
TTL
CLKO
O
—
In RC mode, OSC2 pin outputs CLKOUT which
has 1/4 the frequency of OSC1 and denotes the
instruction cycle rate.
Digital I/O.
OSC2
O
—
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
RA7/CLKI/OSC1
RA7
I/O
CLKI
I
TTL
Digital I/O.
OSC1
I
ST
Oscillator crystal input or external clock source
input ST buffer when configured in RC mode;
CMOS otherwise.
CMOS External clock source input. Always associated
with pin function OSC1.
RB0/INT0/FLT0/SRI/AN12
RB0
I/O
TTL
Digital I/O.
INT0
I
ST
External interrupt 0.
FLT0
I
ST
PWM Fault input for ECCP Auto-Shutdown.
SRI
I
ST
SR Latch input.
AN12
I
Analog Analog input 12.
RB1/INT1/C12IN3-/AN10
RB1
I/O
TTL
Digital I/O.
INT1
I
ST
External interrupt 1.
C12IN3-
I
Analog Comparators C1 and C2 inverting input.
AN10
I
Analog Analog input 10.
RB2/INT2/CTED1/AN8
RB2
I/O
TTL
INT2
I
ST
Digital I/O.
External interrupt 2.
CTED1
I
ST
CTMU Edge 1 input.
AN8
I
Analog Analog input 8.
RB3/CTED2/P2A/CCP2/C12IN2-/AN9
RB3
I/O
TTL
Digital I/O.
CTED2
I
ST
CTMU Edge 2 input.
P2A(2)
O
CCP2(2)
I/O
C12IN2-
I
Analog Comparators C1 and C2 inverting input.
AN9
I
Analog Analog input 9.
CMOS Enhanced CCP2 PWM output.
ST
Capture 2 input/Compare 2 output/PWM 2 output.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
DS41412C-page 22
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
TQFP
QFN
UQFN
37
14
14
12
38
15
15
13
Pin
Type
Buffer
Type
RB4
I/O
TTL
Digital I/O.
IOC0
I
TTL
Interrupt-on-change pin.
T5G
I
ST
Timer5 external clock gate input.
AN11
I
Pin Name
RB4/IOC0/T5G/AN11
40
15
16
16
17
32
35
16
17
34
35
14
15
30
31
RB5
I/O
TTL
Digital I/O.
IOC1
I
TTL
Interrupt-on-change pin.
P3A(1)
O
CCP3(1)
I/O
ST
Capture 3 input/Compare 3 output/PWM 3 output.
(2)
36
Legend:
Note
36
32
CMOS Enhanced CCP3 PWM output.
I
ST
Timer3 clock input.
T1G
I
ST
Timer1 external clock gate input.
AN13
I
Analog Analog input 13.
RB6/IOC2/PGC
RB6
I/O
TTL
Digital I/O.
IOC2
I
TTL
Interrupt-on-change pin.
PGC
I/O
ST
In-Circuit Debugger and ICSP™ programming
clock pin.
RB7/IOC3/PGD
RB7
I/O
TTL
Digital I/O.
IOC3
I
TTL
Interrupt-on-change pin.
PGD
I/O
ST
In-Circuit Debugger and ICSP™ programming
data pin.
TTL
Digital I/O.
RC0/P2B/T3CKI/T3G/T1CKI/SOSCO
RC0
I/O
P2B(2)
O
T3CKI(1)
I
ST
Timer3 clock input.
T3G
I
ST
Timer3 external clock gate input.
T1CKI
I
ST
Timer1 clock input.
SOSCO
O
—
Secondary oscillator output.
I/O
TTL
CMOS Enhanced CCP1 PWM output.
RC1/P2A/CCP2/SOSCI
RC1
17
Analog Analog input 11.
RB5/IOC1/P3A/CCP3/T3CKI/T1G/AN13
T3CKI
39
Description
P2A(1)
O
CCP2(1)
I/O
SOSCI
I
Digital I/O.
CMOS Enhanced CCP2 PWM output.
ST
Capture 2 input/Compare 2 output/PWM 2 output.
Analog Secondary oscillator input.
RC2/CTPLS/P1A/CCP1/T5CKI/AN14
RC2
I/O
TTL
CTPLS
O
—
P1A
O
CCP1
I/O
T5CKI
I
AN14
I
Digital I/O.
CTMU pulse generator output.
CMOS Enhanced CCP1 PWM output.
ST
Capture 1 input/Compare 1 output/PWM 1 output.
ST
Timer5 clock input.
Analog Analog input 14.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 23
PIC18(L)F2X/4XK22
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
TQFP
QFN
UQFN
18
37
37
33
23
24
25
26
19
20
42
43
44
43
44
1
1
38
39
Legend:
Note
42
38
39
38
39
40
1
34
35
Pin
Type
Buffer
Type
RC3
I/O
TTL
Digital I/O.
SCK1
I/O
ST
Synchronous serial clock input/output for SPI
mode (MSSP2).
SCL1
I/O
ST
Synchronous serial clock input/output for I2C™
mode (MSSP2).
AN15
I
Pin Name
Description
RC3/SCK1/SCL1/AN15
Analog Analog input 15.
RC4/SDI1/SDA1/AN16
RC4
I/O
TTL
Digital I/O.
SDI1
I
ST
SPI data in (MSSP1).
SDA1
I/O
ST
I2C™ data I/O (MSSP1).
AN16
I
Analog Analog input 16.
RC5/SDO1/AN17
RC5
I/O
TTL
SDO1
O
—
AN17
I
Digital I/O.
SPI data out (MSSP1).
Analog Analog input 17.
RC6/TX1/CK1/AN18
RC6
I/O
TTL
TX1
O
—
EUSART 1 asynchronous transmit.
Digital I/O.
CK1
I/O
ST
EUSART 1 synchronous clock (see related RXx/
DTx).
AN18
I
Analog Analog input 18.
RC7/RX1/DT1/AN19
RC7
I/O
TTL
Digital I/O.
RX1
I
ST
EUSART 1 asynchronous receive.
DT1
I/O
ST
EUSART 1 synchronous data (see related TXx/
CKx).
AN19
I
Analog Analog input 19.
RD0/SCK2/SCL2/AN20
RD0
I/O
TTL
Digital I/O.
SCK2
I/O
ST
Synchronous serial clock input/output for SPI
mode (MSSP2).
SCL2
I/O
ST
Synchronous serial clock input/output for I2C™
mode (MSSP2).
AN20
I
Analog Analog input 20.
RD1/CCP4/SDI2/SDA2/AN21
RD1
I/O
TTL
Digital I/O.
CCP4
I/O
ST
Capture 4 input/Compare 4 output/PWM 4 output.
SDI2
I
ST
SPI data in (MSSP2).
SDA2
I/O
ST
I2C™ data I/O (MSSP2).
AN21
I
Analog Analog input 21.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
DS41412C-page 24
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
TQFP
QFN
UQFN
21
40
40
36
22
27
28
29
30
8
9
41
2
Note
2
3
3
4
4
5
5
25
26
Legend:
41
25
26
37
2
3
4
5
23
24
Pin
Type
Buffer
Type
RD2
I/O
TTL
P2B(1)
O
CMOS Enhanced CCP2 PWM output.
AN22
I
Analog Analog input 22.
Pin Name
Description
RD2/P2B/AN22
Digital I/O
RD3/P2C/SS2/AN23
RD3
I/O
P2C
O
SS2
I
AN23
I
TTL
Digital I/O.
CMOS Enhanced CCP2 PWM output.
TTL
SPI slave select input (MSSP2).
Analog Analog input 23.
RD4/P2D/SDO2/AN24
RD4
I/O
P2D
O
SDO2
O
AN24
I
TTL
Digital I/O.
CMOS Enhanced CCP2 PWM output.
—
SPI data out (MSSP2).
Analog Analog input 24.
RD5/P1B/AN25
RD5
I/O
P1B
O
CMOS Enhanced CCP1 PWM output.
TTL
Digital I/O.
AN25
I
Analog Analog input 25.
RD6/P1C/TX2/CK2/AN26
RD6
I/O
P1C
O
TTL
Digital I/O.
TX2
O
—
EUSART 2 asynchronous transmit.
CK2
I/O
ST
EUSART 2 synchronous clock (see related RXx/
DTx).
AN26
I
CMOS Enhanced CCP1 PWM output.
Analog Analog input 26.
RD7/P1D/RX2/DT2/AN27
RD7
I/O
P1D
O
TTL
Digital I/O.
RX2
I
ST
EUSART 2 asynchronous receive.
DT2
I/O
ST
EUSART 2 synchronous data (see related TXx/
CKx).
AN27
I
CMOS Enhanced CCP1 PWM output.
Analog Analog input 27.
RE0/P3A/CCP3/AN5
RE0
I/O
P3A(2)
O
CCP3(2)
I/O
AN5
I
TTL
Digital I/O.
CMOS Enhanced CCP3 PWM output.
ST
Capture 3 input/Compare 3 output/PWM 3 output.
Analog Analog input 5.
RE1/P3B/AN6
RE1
I/O
P3B
O
CMOS Enhanced CCP3 PWM output.
TTL
Digital I/O.
AN6
I
Analog Analog input 6.
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 25
PIC18(L)F2X/4XK22
TABLE 1-3:
PIC18(L)F4XK22 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number
PDIP
TQFP
QFN
UQFN
10
27
27
25
1
18
18
16
Pin
Type
Buffer
Type
RE2
I/O
TTL
Digital I/O.
CCP5
I/O
ST
Capture 5 input/Compare 5 output/PWM 5 output
AN7
I
Pin Name
Description
RE2/CCP5/AN7
Analog Analog input 7.
RE3/VPP/MCLR
RE3
I
ST
Digital input.
VPP
P
MCLR
I
ST
Active-low Master Clear (device Reset) input.
Programming voltage input.
11,32
7, 28
7, 8,
28, 29
7, 26
VDD
P
—
Positive supply for logic and I/O pins.
12,31
6, 29
6,30,
31
6, 27
VSS
P
—
Ground reference for logic and I/O pins.
12,13,
33,34
13
Legend:
Note
NC
TTL = TTL compatible input CMOS = CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels;
I = Input; O = Output; P = Power.
1:
Default pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX, CCP3MX
and CCP2MX are set.
2:
Alternate pin assignment for P2B, T3CKI, CCP3/P3A and CCP2/P2A when Configuration bits PB2MX, T3CMX,
CCP3MX and CCP2MX are clear.
DS41412C-page 26
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.0
OSCILLATOR MODULE (WITH
FAIL-SAFE CLOCK MONITOR)
2.1
Overview
The HFINTOSC, MFINTOSC and LFINTOSC are
factory calibrated high, medium and low-frequency
oscillators, respectively, which are used as the internal
clock sources.
The oscillator module has a wide variety of clock
sources and selection features that allow it to be used
in a wide range of applications while maximizing performance and minimizing power consumption. Figure 2-1
illustrates a block diagram of the oscillator module.
Clock sources can be configured from external
oscillators, quartz crystal resonators, ceramic resonators
and Resistor-Capacitor (RC) circuits. In addition, the
system clock source can be configured from one of three
internal oscillators, with a choice of speeds selectable via
software. Additional clock features include:
• Selectable system clock source between external
or internal sources via software.
• Two-Speed Start-up mode, which minimizes
latency between external oscillator start-up and
code execution.
• Fail-Safe Clock Monitor (FSCM) designed to
detect a failure of the external clock source (LP,
XT, HS, EC or RC modes) and switch
automatically to the internal oscillator.
• Oscillator Start-up Timer (OST) ensures stability
of crystal oscillator sources.
The primary clock module can be configured to provide
one of six clock sources as the primary clock.
1.
2.
3.
4.
5.
6.
RC
LP
XT
INTOSC
HS
EC
External Resistor/Capacitor
Low-Power Crystal
Crystal/Resonator
Internal Oscillator
High-Speed Crystal/Resonator
External Clock
The HS and EC oscillator circuits can be optimized for
power consumption and oscillator speed using settings
in FOSC<3:0>. Additional FOSC<3:0> selections
enable RA6 to be used as I/O or CLKO (FOSC/4) for
RC, EC and INTOSC Oscillator modes.
Primary Clock modes are selectable by the
FOSC<3:0> bits of the CONFIG1H Configuration
register. The primary clock operation is further defined
by these Configuration and register bits:
1.
2.
3.
4.
5.
6.
7.
8.
PRICLKEN (CONFIG1H<5>)
PRISD (OSCCON2<2>)
PLLCFG (CONFIG1H<4>)
PLLEN (OSCTUNE<6>)
HFOFST (CONFIG3H<3>)
IRCF<2:0> (OSCCON<6:4>)
MFIOSEL (OSCCON2<4>)
INTSRC (OSCTUNE<7>)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 27
PIC18(L)F2X/4XK22
FIGURE 2-1:
SIMPLIFIED OSCILLATOR SYSTEM BLOCK DIAGRAM
Secondary Oscillator(1)
SOSCO
Secondary
Oscillator
(SOSC)
SOSCI
Low-Power Mode
Event Switch
(SCS<1:0>)
SOSCOUT
2
Primary Clock Module
Secondary
Oscillator
PRICLKEN
PRISD
PLL Select (3) (4)
OSC2
OSC1
FOSC<3:0>(5)
Primary
Oscillator(2)
( OSC)
Primary Oscillator
INTOSC
0
4xPLL
0
Primary
Clock
00
1
1
INTOSC
Clock Switch MUX
EN
01
1x
Internal Oscillator
IRCF<2:0>
MFIOSEL
INTSRC
3
3
INTOSC
Divide
Circuit
HF-16 MHZ
HF-8 MHZ
HF-4 MHZ
HF-2 MHZ
HF-1 MHZ
HF-500 kHZ
HF-250 kHZ
HF-31.25 kHZ
MFINTOSC
(500 kHz)
MF-500 kHZ
MF-250 kHZ
MF-31.25 kHZ
LFINTOSC
Internal Oscillator MUX(3)
HFINTOSC
(16 MHz)
INTOSC
LF-31.25 kHz
(31.25 kHz)
Note 1: Details in Figure 2-4.
2: Details in Figure 2-2.
3: Details in Figure 2-3.
4: Details in Table 2-1.
5: The Primary Oscillator MUX uses the INTOSC branch when FOSC<3:0> = 100x.
DS41412C-page 28
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.2
Oscillator Control
2.2.3
The OSCCON, OSCCON2 and OSCTUNE registers
(Register 2-1 to Register 2-3) control several aspects
of the device clock’s operation, both in full-power
operation and in power-managed modes.
•
•
•
•
•
•
Main System Clock Selection (SCS)
Primary Oscillator Circuit Shutdown (PRISD)
Secondary Oscillator Enable (SOSCGO)
Primary Clock Frequency 4x multiplier (PLLEN)
Internal Frequency selection bits (IRCF, INTSRC)
Clock Status bits (OSTS, HFIOFS, MFIOFS,
LFIOFS. SOSCRUN, PLLRDY)
• Power management selection (IDLEN)
2.2.1
MAIN SYSTEM CLOCK SELECTION
The System Clock Select bits, SCS<1:0>, select the
main clock source. The available clock sources are
• Primary clock defined by the FOSC<3:0> bits of
CONFIG1H. The primary clock can be the primary
oscillator, an external clock, or the internal
oscillator block.
• Secondary clock (secondary oscillator)
• Internal oscillator block (HFINTOSC, MFINTOSC
and LFINTOSC).
LOW FREQUENCY SELECTION
When a nominal output frequency of 31.25 kHz is
selected (IRCF<2:0> = 000), users may choose
which internal oscillator acts as the source. This is
done with the INTSRC bit of the OSCTUNE register
and MFIOSEL bit of the OSCCON2 register. See
Figure 2-2 and Register 2-1 for specific 31.25 kHz
selection. This option allows users to select a
31.25 kHz clock (MFINTOSC or HFINTOSC) that can
be tuned using the TUN<5:0> bits in OSCTUNE
register, while maintaining power savings with a very
low clock speed. LFINTOSC always remains the
clock source for features such as the Watchdog Timer
and the Fail-Safe Clock Monitor, regardless of the
setting of INTSRC and MFIOSEL bits
This option allows users to select the tunable and more
precise HFINTOSC as a clock source, while
maintaining power savings with a very low clock speed.
2.2.4
POWER MANAGEMENT
The IDLEN bit of the OSCCON register determines
whether the device goes into Sleep mode or one of the
Idle modes when the SLEEP instruction is executed.
The clock source changes immediately after one or
more of the bits is written to, following a brief clock
transition interval. The SCS bits are cleared to select
the primary clock on all forms of Reset.
2.2.2
INTERNAL FREQUENCY
SELECTION
The Internal Oscillator Frequency Select bits
(IRCF<2:0>) select the frequency output of the internal
oscillator block. The choices are the LFINTOSC source
(31.25 kHz), the MFINTOSC source (31.25 kHz,
250 kHz or 500 kHz) and the HFINTOSC source
(16 MHz) or one of the frequencies derived from the
HFINTOSC postscaler (31.25 kHz to 8 MHz). If the
internal oscillator block is supplying the main clock,
changing the states of these bits will have an immediate change on the internal oscillator’s output. On
device Resets, the output frequency of the internal
oscillator is set to the default frequency of 1 MHz.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 29
PIC18(L)F2X/4XK22
FIGURE 2-2:
INTERNAL OSCILLATOR
MUX BLOCK DIAGRAM
FIGURE 2-3:
FOSC<3:0> = 100x
PLLCFG
IRCF<2:0>
MFIOSEL
INTSRC
PLL
3
HF-16 MHZ
HF-8 MHZ
HF-4 MHZ
HF-2 MHZ
HF-1 MHZ
PLLEN
Select
111
110
101
100
011
MF-500 KHZ
1
HF-500 KHZ
500 kHZ
010
250 kHZ
001
0
MF-250 KHZ
1
HF-250 KHZ
INTOSC
0
HF-31.25 KHZ 11
MF-31.25 KHZ 10
LF-31.25 KHZ
0X
TABLE 2-1:
PLL SELECT BLOCK
DIAGRAM
31.25 kHZ
000
PLL SELECT TRUTH TABLE
Primary Clock MUX Source
FOSC<3:0>
PLLCFG
PLLEN
PLL Select
FOSC (any source)
0000-1111
0
0
0
OSC1/OSC2 (external source)
0000-0111
1010-1111
1
x
1
0
1
1
1000-1001
x
0
0
x
1
1
INTOSC (internal source)
INTOSC (internal source)
DS41412C-page 30
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 2-4:
SECONDARY OSCILLATOR AND EXTERNAL CLOCK INPUTS
SOSCGO
T1SOSCEN
T3SOSCEN
T5SOSCEN
SOSCEN
To Clock Switch Module
SOSCI
EN
SOSCOUT
Secondary
Oscillator
SOSCO
T1CKI
T3G
T3CKI
1
T1CLK_EXT_SRC
SOSCEN
0
T1SOSCEN
SOSCEN
T3G
SOSCEN
1
T3CLK_EXT_SRC
0
0
1
T3CKI
T1G
T3SOSCEN
T3CMX
T1G
1
T5CLK_EXT_SRC
0
T5CKI
T5SOSCEN
T5G
 2010 Microchip Technology Inc.
T5G
Preliminary
DS41412C-page 31
PIC18(L)F2X/4XK22
REGISTER 2-1:
R/W-0
OSCCON: OSCILLATOR CONTROL REGISTER
R/W-0
IDLEN
R/W-1
R/W-1
IRCF<2:0>
R-q
R-0
OSTS(1)
HFIOFS
R/W-0
R/W-0
SCS<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
q = depends on condition
-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 Idle mode on SLEEP instruction
0 = Device enters Sleep mode on SLEEP instruction
bit 6-4
IRCF<2:0>: Internal RC Oscillator Frequency Select bits(2)
111 = HFINTOSC – (16 MHz)
110 = HFINTOSC/2 – (8 MHz)
101 = HFINTOSC/4 – (4 MHz)
100 = HFINTOSC/8 – (2 MHz)
011 = HFINTOSC/16 – (1 MHz)(3)
If INTSRC = 0 and MFIOSEL = 0:
010 = HFINTOSC/32 – (500 kHz)
001 = HFINTOSC/64 – (250 kHz)
000 = LFINTOSC – (31.25 kHz)
If INTSRC = 1 and MFIOSEL = 0:
010 = HFINTOSC/32 – (500 kHz)
001 = HFINTOSC/64 – (250 kHz)
000 = HFINTOSC/512 – (31.25 kHz)
If INTSRC = 0 and MFIOSEL = 1:
010 = MFINTOSC – (500 kHz)
001 = MFINTOSC/2 – (250 kHz)
000 = LFINTOSC – (31.25 kHz)
If INTSRC = 1 and MFIOSEL = 1:
010 = MFINTOSC – (500 kHz)
001 = MFINTOSC/2 – (250 kHz)
000 = MFINTOSC/16 – (31.25 kHz)
bit 3
OSTS: Oscillator Start-up Time-out Status bit
1 = Device is running from the clock defined by FOSC<3:0> of the CONFIG1H register
0 = Device is running from the internal oscillator (HFINTOSC, MFINTOSC or LFINTOSC)
bit 2
HFIOFS: HFINTOSC Frequency Stable bit
1 = HFINTOSC frequency is stable
0 = HFINTOSC frequency is not stable
bit 1-0
SCS<1:0>: System Clock Select bit
1x = Internal oscillator block
01 = Secondary (SOSC) oscillator
00 = Primary clock (determined by FOSC<3:0> in CONFIG1H).
Note 1:
2:
3:
Reset state depends on state of the IESO Configuration bit.
INTOSC source may be determined by the INTSRC bit in OSCTUNE and the MFIOSEL bit in OSCCON2.
Default output frequency of HFINTOSC on Reset.
DS41412C-page 32
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 2-2:
OSCCON2: OSCILLATOR CONTROL REGISTER 2
R-0/0
R-0/q
U-0
R/W-0/0
R/W-0/u
R/W-1/1
R-x/u
R-0/0
PLLRDY
SOSCRUN
—
MFIOSEL
SOSCGO(1)
PRISD
MFIOFS
LFIOFS
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
q = depends on condition
-n/n = Value at POR and BOR/Value at all other Resets
bit 7
PLLRDY: PLL Run Status bit
1 = System clock comes from 4xPLL
0 = System clock comes from an oscillator, other than 4xPLL
bit 6
SOSCRUN: SOSC Run Status bit
1 = System clock comes from secondary SOSC
0 = System clock comes from an oscillator, other than SOSC
bit 5
Unimplemented: Read as ‘0’.
bit 4
MFIOSEL: MFINTOSC Select bit
1 = MFINTOSC is used in place of HFINTOSC frequencies of 500 kHz, 250 kHz and 31.25 kHz
0 = MFINTOSC is not used
bit 3
SOSCGO(1): Secondary Oscillator Start Control bit
1 = Secondary oscillator is enabled.
0 = Secondary oscillator is shut off if no other sources are requesting it.
bit 2
PRISD: Primary Oscillator Drive Circuit Shutdown bit
1 = Oscillator drive circuit on
0 = Oscillator drive circuit off (zero power)
bit 1
MFIOFS: MFINTOSC Frequency Stable bit
1 = MFINTOSC is stable
0 = MFINTOSC is not stable
bit 0
LFIOFS: LFINTOSC Frequency Stable bit
1 = LFINTOSC is stable
0 = LFINTOSC is not stable
Note 1:
The SOSCGO bit is only reset on a POR Reset.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 33
PIC18(L)F2X/4XK22
2.3
Clock Source Modes
Clock Source modes can be classified as external or
internal.
2.4
External Clock Modes
2.4.1
OSCILLATOR START-UP TIMER (OST)
• External Clock modes rely on external circuitry for
the clock source. Examples are: Clock modules
(EC mode), quartz crystal resonators or ceramic
resonators (LP, XT and HS modes) and ResistorCapacitor (RC mode) circuits.
• Internal clock sources are contained internally
within the Oscillator block. The Oscillator block
has three internal oscillators: the 16 MHz HighFrequency Internal Oscillator (HFINTOSC),
500 kHz Medium-Frequency Internal Oscillator
(MFINTOSC) and the 31.25 kHz Low-Frequency
Internal Oscillator (LFINTOSC).
When the oscillator module is configured for LP, XT or
HS modes, the Oscillator Start-up Timer (OST) counts
1024 oscillations from OSC1. This occurs following a
Power-on Reset (POR) and when the Power-up Timer
(PWRT) has expired (if configured), or a wake-up from
Sleep. During this time, the program counter does not
increment and program execution is suspended. The
OST ensures that the oscillator circuit, using a quartz
crystal resonator or ceramic resonator, has started and
is providing a stable system clock to the oscillator
module. When switching between clock sources, a
delay is required to allow the new clock to stabilize.
These oscillator delays are shown in Table 2-2.
The system clock can be selected between external or
internal clock sources via the System Clock Select
(SCS<1:0>) bits of the OSCCON register. See
Section 2.9 “Clock Switching” for additional
information.
In order to minimize latency between external oscillator
start-up and code execution, the Two-Speed Clock
Start-up mode can be selected (see Section 2.10
“Two-Speed Clock Start-up Mode”).
TABLE 2-2:
OSCILLATOR DELAY EXAMPLES
Switch From
Switch To
Frequency
Oscillator Delay
Sleep/POR
LFINTOSC
MFINTOSC
HFINTOSC
31.25 kHz
31.25 kHz to 500 kHz
31.25 kHz to 16 MHz
Sleep/POR
EC, RC
DC – 64 MHz
2 instruction cycles
LFINTOSC (31.25 kHz)
EC, RC
DC – 64 MHz
1 cycle of each
Oscillator Warm-Up Delay (TWARM)
Sleep/POR
LP, XT, HS
32 kHz to 40 MHz
1024 Clock Cycles (OST)
Sleep/POR
4xPLL
32 MHz to 64 MHz
1024 Clock Cycles (OST) + 2 ms
LFINTOSC
HFINTOSC
31.25 kHz to 16 MHz
LFINTOSC (31.25 kHz)
2.4.2
EC MODE
1 s (approx.)
FIGURE 2-5:
The External Clock (EC) mode allows an externally
generated logic level as the system clock source. When
operating in this mode, an external clock source is
connected to the OSC1 input and the OSC2 is available
for general purpose I/O. Figure 2-5 shows the pin
connections for EC mode.
The External Clock (EC) mode offers a Medium Power
(MP) and a High Power (HP) option selectable by the
FOSC<3:0> bits. The MP selections are best suited for
external clock frequencies between 4 and 16 MHz. The
HP selection is best suited for clock frequencies above
16 MHz.
EXTERNAL CLOCK (EC)
MODE OPERATION
OSC1/CLKIN
Clock from
Ext. System
PIC® MCU
I/O
Note 1:
OSC2/CLKOUT(1)
Alternate pin functions are listed in
Section 1.0 “Device Overview”.
The Oscillator Start-up Timer (OST) is disabled when
EC mode is selected. Therefore, there is no delay in
operation after a Power-on Reset (POR) or wake-up
from Sleep. Because the PIC® MCU design is fully
static, stopping the external clock input will have the
effect of halting the device while leaving all data intact.
Upon restarting the external clock, the device will
resume operation as if no time had elapsed.
DS41412C-page 34
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.4.3
LP, XT, HS MODES
The LP, XT and HS modes support the use of quartz
crystal resonators or ceramic resonators connected to
OSC1 and OSC2 (Figure 2-6). The mode selects a low,
medium or high gain setting of the internal inverteramplifier to support various resonator types and speed.
Note 1: Quartz crystal characteristics vary according
to type, package and manufacturer. The
user should consult the manufacturer data
sheets for specifications and recommended
application.
2: Always verify oscillator performance over
the VDD and temperature range that is
expected for the application.
LP Oscillator mode selects the lowest gain setting of the
internal inverter-amplifier. LP mode current consumption
is the least of the three modes. This mode is best suited
to drive resonators with a low drive level specification, for
example, tuning fork type crystals.
3: For oscillator design assistance, refer to the
following Microchip Application Notes:
• AN826, “Crystal Oscillator Basics and
Crystal Selection for rfPIC® and PIC®
Devices” (DS00826)
• AN849, “Basic PIC® Oscillator Design”
(DS00849)
• AN943, “Practical PIC® Oscillator
Analysis and Design” (DS00943)
• AN949, “Making Your Oscillator Work”
(DS00949)
XT Oscillator mode selects the intermediate gain
setting of the internal inverter-amplifier. XT mode
current consumption is the medium of the three modes.
This mode is best suited to drive resonators with a
medium drive level specification.
HS Oscillator mode offers a Medium Power (MP) and a
High Power (HP) option selectable by the FOSC<3:0>
bits. The MP selections are best suited for oscillator
frequencies between 4 and 16 MHz. The HP selection
has the highest gain setting of the internal inverteramplifier and is best suited for frequencies above
16 MHz. HS mode is best suited for resonators that
require a high drive setting.
FIGURE 2-6:
FIGURE 2-7:
CERAMIC RESONATOR
OPERATION
(XT OR HS MODE)
QUARTZ CRYSTAL
OPERATION (LP, XT OR
HS MODE)
PIC® MCU
OSC1/CLKIN
C1
To Internal
Logic
PIC® MCU
RP(3)
OSC1/CLKIN
C1
To Internal
Logic
Quartz
Crystal
C2
RS(1)
RF(2)
C2 Ceramic
RS(1)
Resonator
Sleep
Sleep
OSC2/CLKOUT
Note 1: A series resistor (RS) may be required for
ceramic resonators with low drive level.
OSC2/CLKOUT
Note 1:
A series resistor (RS) may be required for
quartz crystals with low drive level.
2:
The value of RF varies with the Oscillator mode
selected (typically between 2 M to 10 M.
 2010 Microchip Technology Inc.
RF(2)
Preliminary
2: The value of RF varies with the Oscillator mode
selected (typically between 2 M to 10 M.
3: An additional parallel feedback resistor (RP)
may be required for proper ceramic resonator
operation.
DS41412C-page 35
PIC18(L)F2X/4XK22
2.4.4
2.5
EXTERNAL RC MODES
The external Resistor-Capacitor (RC) modes support
the use of an external RC circuit. This allows the
designer maximum flexibility in frequency choice while
keeping costs to a minimum when clock accuracy is not
required. There are two modes: RC and RCIO.
2.4.4.1
FIGURE 2-8:
1.
PIC® MCU
REXT
OSC1/CLKIN
Internal
Clock
CEXT
FOSC/4 or
I/O(2)
OSC2/CLKOUT(1)
The system clock speed can be selected via software
using the Internal Oscillator Frequency select bits
IRCF<2:0> of the OSCCON register.
2.5.1
Recommended values: 10 k  REXT  100 k
CEXT > 20 pF
2:
The HFINTOSC (High-Frequency Internal
Oscillator) is factory calibrated and operates at
16 MHz. The frequency of the HFINTOSC can
be user-adjusted via software using the
OSCTUNE register (Register 2-3).
The MFINTOSC (Medium-Frequency Internal
Oscillator) is factory calibrated and operates
at 500 kHz. The frequency of the MFINTOSC
can be user-adjusted via software using the
OSCTUNE register (Register 2-3).
The LFINTOSC (Low-Frequency Internal
Oscillator) is factory calibrated and operates at
31.25 kHz. The LFINTOSC cannot be useradjusted, but is designed to be stable over
temperature and voltage.
The system clock can be selected between external or
internal clock sources via the System Clock Selection
(SCS<1:0>) bits of the OSCCON register. See
Section 2.9 “Clock Switching” for more information.
VSS
Note 1:
2.
3.
EXTERNAL RC MODES
VDD
2.4.4.2
The oscillator module has three independent, internal
oscillators that can be configured or selected as the
system clock source.
RC Mode
In RC mode, the RC circuit connects to OSC1. OSC2/
CLKOUT outputs the RC oscillator frequency divided
by 4. This signal may be used to provide a clock for
external circuitry, synchronization, calibration, test or
other application requirements. Figure 2-8 shows the
external RC mode connections.
Internal Clock Modes
Alternate pin functions are listed in
Section 1.0 “Device Overview”.
Output depends upon RC or RCIO clock mode.
RCIO Mode
In RCIO mode, the RC circuit is connected to OSC1.
OSC2 becomes a general purpose I/O pin.
The RC oscillator frequency is a function of the supply
voltage, the resistor (REXT) and capacitor (CEXT) values
and the operating temperature. Other factors affecting
the oscillator frequency are:
INTOSC WITH I/O OR CLOCKOUT
Two of the clock modes selectable with the FOSC<3:0>
bits of the CONFIG1H Configuration register configure
the internal oscillator block as the primary oscillator.
Mode selection determines whether OSC2/CLKOUT/
RA7 will be configured as general purpose I/O (RA7) or
FOSC/4 (CLKOUT). In both modes, OSC1/CLKIN/RA7
is configured as general purpose I/O. See
Section 24.0 “Special Features of the CPU” for more
information.
The CLKOUT signal may be used to provide a clock for
external circuitry, synchronization, calibration, test or
other application requirements.
• input threshold voltage variation
• component tolerances
• packaging variations in capacitance
The user also needs to take into account variation due
to tolerance of external RC components used.
DS41412C-page 36
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.5.1.1
OSCTUNE Register
The HFINTOSC/MFINTOSC oscillator circuits are
factory calibrated but can be adjusted in software by
writing to the TUN<5:0> bits of the OSCTUNE register
(Register 2-3).
The default value of the TUN<5:0> is ‘000000’. The
value is a 6-bit two’s complement number.
When the OSCTUNE register is modified, the
HFINTOSC/MFINTOSC frequency will begin shifting to
the new frequency. Code execution continues during this
shift. There is no indication that the shift has occurred.
The TUN<5:0> bits in OSCTUNE do not affect the
LFINTOSC frequency. Operation of features that
depend on the LFINTOSC clock source frequency, such
REGISTER 2-3:
as the Power-up Timer (PWRT), Watchdog Timer
(WDT), Fail-Safe Clock Monitor (FSCM) and
peripherals, are not affected by the change in frequency.
The OSCTUNE register also implements the INTSRC
and PLLEN bits, which control certain features of the
internal oscillator block.
The INTSRC bit allows users to select which internal
oscillator provides the clock source when the
31.25 kHz frequency option is selected. This is covered
in greater detail in Section 2.2.3 “Low Frequency
Selection”.
The PLLEN bit controls the operation of the frequency
multiplier, PLL, in internal oscillator modes. For more
details about the function of the PLLEN bit, see
Section 2.6.2 “PLL in HFINTOSC Modes”
OSCTUNE: OSCILLATOR TUNING REGISTER
R/W-0
R/W-0
INTSRC
PLLEN(1)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
TUN<5:0>
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
INTSRC: Internal Oscillator Low-Frequency Source Select bit
1 = 31.25 kHz device clock derived from the MFINTOSC or HFINTOSC source
0 = 31.25 kHz device clock derived directly from LFINTOSC internal oscillator
bit 6
PLLEN: Frequency Multiplier 4xPLL for HFINTOSC Enable bit(1)
1 = PLL enabled for HFINTOSC (8 MHz and 16 MHz only)
0 = PLL disabled
bit 5-0
TUN<5:0>: Frequency Tuning bits – use to adjust MFINTOSC and HFINTOSC frequencies
011111 = Maximum frequency
011110 =
•••
000001 =
000000 = Oscillator module (HFINTOSC and MFINTOSC) are running at the factory calibrated
frequency.
111111 =
•••
100000 = Minimum frequency
Note 1:
The PLLEN bit is active only when the HFINTOSC is the primary clock source (FOSC<2:0> = 100X) and
the selected frequency is 8 MHz or 16 MHz (IRCF<2:0> = 11x). Otherwise, the PLLEN bit is unavailable
and always reads ‘0’.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 37
PIC18(L)F2X/4XK22
2.5.2
LFINTOSC
2.5.4.1
The Low-Frequency Internal Oscillator (LFINTOSC) is
a 31.25 kHz internal clock source. The LFINTOSC is
not tunable, but is designed to be stable across temperature and voltage. See Section 27.0 “Electrical Characteristics”
for
the
LFINTOSC
accuracy
specifications.
The output of the LFINTOSC can be a clock source to
the primary clock or the INTOSC clock (see Figure 2-1).
The LFINTOSC is also the clock source for the Powerup Timer (PWRT), Watchdog Timer (WDT) and Fail-Safe
Clock Monitor (FSCM).
2.5.3
FREQUENCY SELECT BITS (IRCF)
The HFINTOSC (16 MHz) and MFINTOSC (500 MHz)
outputs connect to a divide circuit that provides
frequencies of 16 MHz to 31.25 kHz. These divide
circuit frequencies, along with the 31.25 kHz
LFINTOSC output, are multiplexed to provide a single
INTOSC clock output (see Figure 2-1). The IRCF<2:0>
bits of the OSCCON register, the MFIOSEL bit of the
OSCCON2 register and the INTSRC bit of the
OSCTUNE register, select the output frequency of the
internal oscillators. One of eight frequencies can be
selected via software:
•
•
•
•
•
•
•
•
16 MHz
8 MHz
4 MHz
2 MHz
1 MHz (Default after Reset)
500 kHz (MFINTOSC or HFINTOSC)
250 kHz (MFINTOSC or HFINTOSC)
31 kHz (LFINTOSC, MFINTOSC or HFINTOSC)
2.5.4
Compensating with the EUSART
An adjustment may be required when the EUSART
begins to generate framing errors or receives data with
errors while in Asynchronous mode. Framing errors
indicate that the device clock frequency is too high; to
adjust for this, decrement the value in OSCTUNE to
reduce the clock frequency. On the other hand, errors
in data may suggest that the clock speed is too low; to
compensate, increment OSCTUNE to increase the
clock frequency.
2.5.4.2
Compensating with the Timers
This technique compares device clock speed to some
reference clock. Two timers may be used; one timer is
clocked by the peripheral clock, while the other is
clocked by a fixed reference source, such as the
Timer1 oscillator.
Both timers are cleared, but the timer clocked by the
reference generates interrupts. When an interrupt
occurs, the internally clocked timer is read and both
timers are cleared. If the internally clocked timer value
is greater than expected, then the internal oscillator
block is running too fast. To adjust for this, decrement
the OSCTUNE register.
2.5.4.3
Compensating with the CCP Module
in Capture Mode
A CCP module can use free running Timer1, Timer3 or
Timer5 clocked by the internal oscillator block and an
external event with a known period (i.e., AC power
frequency). The time of the first event is captured in the
CCPRxH:CCPRxL registers and is recorded for use later.
When the second event causes a capture, the time of the
first event is subtracted from the time of the second
event. Since the period of the external event is known,
the time difference between events can be calculated.
INTOSC FREQUENCY DRIFT
The factory calibrates the internal oscillator block outputs
(HFINTOSC/MFINTOSC) for 16 MHz/500 kHz. However,
this frequency may drift as VDD or temperature changes.
It is possible to adjust the HFINTOSC/MFINTOSC frequency by modifying the value of the TUN<5:0> bits in the
OSCTUNE register. This has no effect on the LFINTOSC
clock source frequency.
If the measured time is much greater than the calculated time, the internal oscillator block is running too
fast; to compensate, decrement the OSCTUNE register.
If the measured time is much less than the calculated
time, the internal oscillator block is running too slow; to
compensate, increment the OSCTUNE register.
Tuning the HFINTOSC/MFINTOSC source requires
knowing when to make the adjustment, in which direction it should be made and, in some cases, how large a
change is needed. Three possible compensation techniques are discussed in the following sections. However,
other techniques may be used.
DS41412C-page 38
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.6
PLL Frequency Multiplier
2.6.2
A Phase Locked Loop (PLL) circuit is provided as an
option for users who wish to use a lower frequency
oscillator circuit or to clock the device up to its highest
rated frequency from the 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.
2.6.1
PLL IN EXTERNAL OSCILLATOR
MODES
PLL IN HFINTOSC MODES
The 4x frequency multiplier can be used with the
internal oscillator block to produce faster device clock
speeds than are normally possible with the internal
oscillator. When enabled, the PLL multiplies the
HFINTOSC by 4 to produce clock rates up to 64 MHz.
Unlike external clock modes, the PLL can only be
controlled through software. The PLLEN control bit of
the OSCTUNE register is used to enable or disable the
PLL operation when the HFINTOSC is used.
The PLL can be enabled for any of the external
oscillator modes using the OSC1/OSC2 pins by either
setting the PLLCFG bit (CONFIG1H<4>), or setting the
PLLEN bit (OSCTUNE<6>). The PLL is designed for
input frequencies of 4 MHz up to 16 MHz. The PLL then
multiplies the oscillator output frequency by 4 to
produce an internal clock frequency up to 64 MHz.
Oscillator frequencies below 4 MHz should not be used
with the PLL.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 39
PIC18(L)F2X/4XK22
2.7
Effects of Power-Managed Modes
on the Various Clock Sources
For more information about the modes discussed in this
section see Section 3.0 “Power-Managed Modes”. A
quick reference list is also available in Table 3-1.
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 secondary oscillator (SOSC) is
operating and providing the device clock. The
secondary oscillator may also run in all powermanaged modes if required to clock Timer1, Timer3 or
Timer5.
In internal oscillator modes (INTOSC_RUN and
INTOSC_IDLE), the internal oscillator block provides
the device clock source. The 31.25 kHz LFINTOSC
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 24.2
“Watchdog
Timer
(WDT)”,
Section 2.10 “Two-Speed Clock Start-up Mode” and
Section 2.11 “Fail-Safe Clock Monitor” for more
information on WDT, Fail-Safe Clock Monitor and TwoSpeed Start-up). The HFINTOSC and MFINTOSC
outputs may be used directly to clock the device or may
be divided down by the postscaler. The HFINTOSC
and MFINTOSC outputs are disabled when the clock is
provided directly from the LFINTOSC output.
When 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 LFINTOSC is required to support WDT operation.
Other features may be operating that do not require a
device clock source (i.e., SSP slave, PSP, INTn pins
and others). Peripherals that may add significant
current consumption are listed in Section 27.8 “DC
Characteristics: Input/Output Characteristics,
PIC18(L)F2X/4XK22”.
DS41412C-page 40
2.8
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 4.5 “Device Reset
Timers”.
The first timer is the Power-up Timer (PWRT), which
provides a fixed delay on power-up. It is enabled by
clearing (= 0) the PWRTEN Configuration bit.
The second timer is the Oscillator Start-up Timer
(OST), intended to keep the chip in Reset until the
crystal oscillator is stable (LP, XT and HS modes). The
OST does this by counting 1024 oscillator cycles
before allowing the oscillator to clock the device.
When the PLL is enabled with external oscillator
modes, the device is kept in Reset for an additional
2 ms, following the OST delay, so the PLL can lock to
the incoming clock frequency.
There is a delay of interval TCSD, following POR, while
the controller becomes ready to execute instructions.
This delay runs concurrently with any other delays.
This may be the only delay that occurs when any of the
EC, RC or INTIOSC modes are used as the primary
clock source.
When the HFINTOSC is selected as the primary clock,
the main system clock can be delayed until the
HFINTOSC is stable. This is user selectable by the
HFOFST bit of the CONFIG3H Configuration register.
When the HFOFST bit is cleared, the main system
clock is delayed until the HFINTOSC is stable. When
the HFOFST bit is set, the main system clock starts
immediately.
In either case, the HFIOFS bit of the OSCCON register
can be read to determine whether the HFINTOSC is
operating and stable.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 2-3:
OSC1 AND OSC2 PIN STATES IN SLEEP MODE
OSC Mode
OSC1 Pin
OSC2 Pin
RC, INTOSC with CLKOUT Floating, external resistor should pull high
At logic low (clock/4 output)
RC with IO
Floating, external resistor should pull high
Configured as PORTA, bit 6
INTOSC with IO
Configured as PORTA, bit 7
Configured as PORTA, bit 6
EC with IO
Floating, pulled by external clock
Configured as PORTA, bit 6
EC with CLKOUT
Floating, pulled by external clock
At logic low (clock/4 output)
LP, XT, HS
Feedback inverter disabled at quiescent
voltage level
Feedback inverter disabled at quiescent
voltage level
Note:
2.9
See Table 4-2 in Section 4.0 “Reset” for time-outs due to Sleep and MCLR Reset.
Clock Switching
The system clock source can be switched between
external and internal clock sources via software using
the System Clock Select (SCS<1:0>) bits of the
OSCCON register.
PIC18(L)F2X/4XK22 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 3.1.2 “Entering Power-Managed Modes”.
2.9.1
SYSTEM CLOCK SELECT
(SCS<1:0>) BITS
The System Clock Select (SCS<1:0>) bits of the
OSCCON register select the system clock source that
is used for the CPU and peripherals.
• When SCS<1:0> = 00, the system clock source is
determined by configuration of the FOSC<3:0>
bits in the CONFIG1H Configuration register.
• When SCS<1:0> = 10, the system clock source is
chosen by the internal oscillator frequency
selected by the INTSRC bit of the OSCTUNE
register, the MFIOSEL bit of the OSCCON2
register and the IRCF<2:0> bits of the OSCCON
register.
• When SCS<1:0> = 01, the system clock source is
the 32.768 kHz secondary oscillator shared with
Timer1, Timer3 and Timer5.
 2010 Microchip Technology Inc.
After a Reset, the SCS<1:0> bits of the OSCCON
register are always cleared.
Note:
2.9.2
Any automatic clock switch, which may
occur from Two-Speed Start-up or Fail-Safe
Clock Monitor, does not update the
SCS<1:0> bits of the OSCCON register.
The user can monitor the SOSCRUN,
MFIOFS and LFIOFS bits of the
OSCCON2 register, and the HFIOFS and
OSTS bits of the OSCCON register to
determine the current system clock source.
OSCILLATOR START-UP TIME-OUT
STATUS (OSTS) BIT
The Oscillator Start-up Time-out Status (OSTS) bit of
the OSCCON register indicates whether the system
clock is running from the external clock source, as
defined by the FOSC<3:0> bits in the CONFIG1H
Configuration register, or from the internal clock
source. In particular, when the primary oscillator is the
source of the primary clock, OSTS indicates that the
Oscillator Start-up Timer (OST) has timed out for LP,
XT or HS modes.
Preliminary
DS41412C-page 41
PIC18(L)F2X/4XK22
2.9.3
2.10
CLOCK SWITCH TIMING
When switching between one oscillator and another,
the new oscillator may not be operating which saves
power (see Figure 2-9). If this is the case, there is a
delay after the SCS<1:0> bits of the OSCCON register
are modified before the frequency change takes place.
The OSTS and IOFS bits of the OSCCON register will
reflect the current active status of the external and
HFINTOSC oscillators. The timing of a frequency
selection is as follows:
1.
2.
3.
4.
5.
6.
7.
SCS<1:0> bits of the OSCCON register are modified.
The old clock continues to operate until the new
clock is ready.
Clock switch circuitry waits for two consecutive
rising edges of the old clock after the new clock
ready signal goes true.
The system clock is held low starting at the next
falling edge of the old clock.
Clock switch circuitry waits for an additional two
rising edges of the new clock.
On the next falling edge of the new clock the low
hold on the system clock is released and new
clock is switched in as the system clock.
Clock switch is complete.
See Figure 2-1 for more details.
Two-Speed Clock Start-up Mode
Two-Speed Start-up mode provides additional power
savings by minimizing the latency between external
oscillator start-up and code execution. In applications
that make heavy use of the Sleep mode, Two-Speed
Start-up will remove the external oscillator start-up
time from the time spent awake and can reduce the
overall power consumption of the device.
This mode allows the application to wake-up from
Sleep, perform a few instructions using the HFINTOSC
as the clock source and go back to Sleep without
waiting for the primary oscillator to become stable.
Note:
Executing a SLEEP instruction will abort
the oscillator start-up time and will cause
the OSTS bit of the OSCCON register to
remain clear.
When the oscillator module is configured for LP, XT or
HS modes, the Oscillator Start-up Timer (OST) is
enabled (see Section 2.4.1 “Oscillator Start-up Timer
(OST)”). The OST will suspend program execution until
1024 oscillations are counted. Two-Speed Start-up
mode minimizes the delay in code execution by
operating from the internal oscillator as the OST is
counting. When the OST count reaches 1024 and the
OSTS bit of the OSCCON register is set, program
execution switches to the external oscillator.
If the HFINTOSC is the source of both the old and new
frequency, there is no start-up delay before the new
frequency is active. This is because the old and new
frequencies are derived from the HFINTOSC via the
postscaler and multiplexer.
2.10.1
Start-up delay specifications are located in
Section 27.0 “Electrical Characteristics”, under AC
Specifications (Oscillator Module).
• Two-Speed Start-up mode is enabled when the
IESO of the CONFIG1H Configuration register is
set.
• SCS<1:0> (of the OSCCON register) = 00.
• FOSC<2:0> bits of the CONFIG1H Configuration
register are configured for LP, XT or HS mode.
TWO-SPEED START-UP MODE
CONFIGURATION
Two-Speed Start-up mode is enabled when all of the
following settings are configured as noted:
Two-Speed Start-up mode becomes active after:
• Power-on Reset (POR) and, if enabled, after
Power-up Timer (PWRT) has expired, or
• Wake-up from Sleep.
DS41412C-page 42
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
2.10.2
1.
2.
3.
4.
5.
6.
TWO-SPEED START-UP
SEQUENCE
2.10.3
Wake-up from Power-on Reset or Sleep.
Instructions begin executing by the internal
oscillator at the frequency set in the IRCF<2:0>
bits of the OSCCON register.
OST enabled to count 1024 external clock
cycles.
OST timed out. External clock is ready.
OSTS is set.
Clock switch finishes according to Figure 2-9
FIGURE 2-9:
High Speed
CHECKING TWO-SPEED CLOCK
STATUS
Checking the state of the OSTS bit of the OSCCON
register will confirm if the microcontroller is running
from the external clock source, as defined by the
FOSC<2:0> bits in CONFIG1H Configuration register,
or the internal oscillator. OSTS = 0 when the external
oscillator is not ready, which indicates that the system
is running from the internal oscillator.
CLOCK SWITCH TIMING
Low Speed
Old Clock
Start-up Time(1)
Clock Sync
Running
New Clock
New Clk Ready
IRCF <2:0> Select Old
Select New
System Clock
Low Speed
High Speed
Old Clock
Start-up Time(1)
Clock Sync
Running
New Clock
New Clk Ready
IRCF <2:0> Select Old
Select New
System Clock
Note 1: Start-up time includes TOST (1024 TOSC) for external clocks, plus TPLL (approx. 2 ms) for HSPLL mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 43
PIC18(L)F2X/4XK22
2.11
Fail-Safe Clock Monitor
2.11.3
The Fail-Safe Clock Monitor (FSCM) allows the device
to continue operating should the external oscillator fail.
The FSCM can detect oscillator failure any time after
the Oscillator Start-up Timer (OST) has expired. The
FSCM is enabled by setting the FCMEN bit in the
CONFIG1H Configuration register. The FSCM is
applicable to all external oscillator modes (LP, XT, HS,
EC, RC and RCIO).
FIGURE 2-10:
FSCM BLOCK DIAGRAM
Clock Monitor
Latch
External
Clock
S
LFINTOSC
Oscillator
÷ 64
31 kHz
(~32 s)
488 Hz
(~2 ms)
R
2.11.1
Both of these conditions restart the OST. While the
OST is running, the device continues to operate from
the INTOSC selected in OSCCON. When the OST
times out, the Fail-Safe condition is cleared and the
device automatically switches over to the external clock
source. The Fail-Safe condition need not be cleared
before the OSCFIF flag is cleared.
RESET OR WAKE-UP FROM SLEEP
Note:
Due to the wide range of oscillator start-up
times, the Fail-Safe circuit is not active
during oscillator start-up (i.e., after exiting
Reset or Sleep). After an appropriate
amount of time, the user should check the
OSTS bit of the OSCCON register to verify
the oscillator start-up and that the system
clock
switchover
has
successfully
completed.
Note:
When the device is configured for FailSafe clock monitoring in either HS, XT, or
LS oscillator modes then the IESO configuration bit should also be set so that the
clock will automatically switch from the
internal clock to the external oscillator
when the OST times out.
Clock
Failure
Detected
FAIL-SAFE DETECTION
The FSCM module detects a failed oscillator by
comparing the external oscillator to the FSCM sample
clock. The sample clock is generated by dividing the
LFINTOSC by 64 (see Figure 2-10). Inside the fail
detector block is a latch. The external clock sets the
latch on each falling edge of the external clock. The
sample clock clears the latch on each rising edge of the
sample clock. A failure is detected when an entire halfcycle of the sample clock elapses before the primary
clock goes low.
2.11.2
• Any Reset
• By toggling the SCS1 bit of the OSCCON register
The FSCM is designed to detect an oscillator failure
after the Oscillator Start-up Timer (OST) has expired.
The OST is used after waking up from Sleep and after
any type of Reset. The OST is not used with the EC or
RC Clock modes so that the FSCM will be active as
soon as the Reset or wake-up has completed. .
Q
Sample Clock
The Fail-Safe condition is cleared by either one of the
following:
2.11.4
Q
FAIL-SAFE CONDITION CLEARING
FAIL-SAFE OPERATION
When the external clock fails, the FSCM switches the
device clock to an internal clock source and sets the bit
flag OSCFIF of the PIR2 register. The OSCFIF flag will
generate an interrupt if the OSCFIE bit of the PIE2
register is also set. The device firmware can then take
steps to mitigate the problems that may arise from a
failed clock. The system clock will continue to be
sourced from the internal clock source until the device
firmware successfully restarts the external oscillator
and switches back to external operation. An automatic
transition back to the failed clock source will not occur.
The internal clock source chosen by the FSCM is
determined by the IRCF<2:0> bits of the OSCCON
register. This allows the internal oscillator to be
configured before a failure occurs.
DS41412C-page 44
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 2-11:
FSCM TIMING DIAGRAM
Sample Clock
Oscillator
Failure
System
Clock
Output
Clock Monitor Output
(Q)
Failure
Detected
OSCFIF
Test
Note:
TABLE 2-4:
Name
INTCON
IPR2
OSCCON
Test
Test
The system clock is normally at a much higher frequency than the sample clock. The relative frequencies in
this example have been chosen for clarity.
REGISTERS ASSOCIATED WITH CLOCK SOURCES
Bit 7
Bit 6
GIE/GIEH PEIE/GIEL
OSCFIP
C1IP
IDLEN
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP CCP2IP
128
OSTS
HFIOFS
SCS<1:0>
32
PRISD
MFIOFS LFIOFS
IRCF<2:0>
MFIOSEL SOSCGO
33
OSCCON2
PLLRDY SOSCRUN
OSCTUNE
INTSRC
PLLEN
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE CCP2IE
124
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF CCP2IF
119
—
TUN<5:0>
37
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used by Clock Sources.
TABLE 2-5:
Name
CONFIGURATION REGISTERS ASSOCIATED WITH CLOCK SOURCES
Bit 7
Bit 6
Bit 5
CONFIG1H
IESO
CONFIG2L
—
—
—
CONFIG3H
MCLRE
—
P2BMX
Bit 4
Bit 3
FCMEN PRICLKEN PLLCFG
Bit 1
Bit 0
FOSC<3:0>
BORV<1:0>
T3CMX
Bit 2
BOREN<1:0>
Register
on Page
351
PWRTEN
352
HFOFST CCP3MX PBADEN CCP2MX
354
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for Clock Sources.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 45
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 46
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
3.0
POWER-MANAGED MODES
3.1.1
The SCS<1:0> bits allow the selection of one of three
clock sources for power-managed modes. They are:
PIC18(L)F2X/4XK22 devices offer a total of seven
operating modes for more efficient power management. These modes provide a variety of options for
selective power conservation in applications where
resources may be limited (i.e., battery-powered
devices).
• the primary clock, as defined by the FOSC<3:0>
Configuration bits
• the secondary clock (the SOSC oscillator)
• the internal oscillator block
There are three categories of power-managed modes:
3.1.2
• Run modes
• Idle modes
• Sleep mode
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. Refer to
Section 2.9 “Clock Switching” for more information.
These categories define which portions of the device
are clocked and sometimes, 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 powersaving features offered on previous PIC® microcontroller
devices. One of the clock switching features allows the
controller to use the secondary oscillator (SOSC) in
place of the primary oscillator. Also included is the Sleep
mode, offered by all PIC® microcontroller devices, where
all device clocks are stopped.
3.1
CLOCK SOURCES
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.
Selecting Power-Managed Modes
Selecting a power-managed mode requires two
decisions:
• Whether or not the CPU is to be clocked
• The selection of a clock source
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 3-1.
TABLE 3-1:
POWER-MANAGED MODES
OSCCON Bits
Mode
Module Clocking
Available Clock and Oscillator Source
IDLEN(1)
SCS<1:0>
CPU
Peripherals
0
N/A
Off
Off
PRI_RUN
N/A
00
Clocked
Clocked
Primary – LP, XT, HS, RC, EC and Internal
Oscillator Block(2).
This is the normal full-power execution mode.
SEC_RUN
N/A
01
Clocked
Clocked
Secondary – SOSC Oscillator
RC_RUN
N/A
1x
Clocked
Clocked
Internal Oscillator Block(2)
PRI_IDLE
1
00
Off
Clocked
Primary – LP, XT, HS, HSPLL, RC, EC
SEC_IDLE
1
01
Off
Clocked
Secondary – SOSC Oscillator
RC_IDLE
1
1x
Off
Clocked
Internal Oscillator Block(2)
Sleep
Note 1:
2:
None – All clocks are disabled
IDLEN reflects its value when the SLEEP instruction is executed.
Includes HFINTOSC and HFINTOSC postscaler, as well as the LFINTOSC source.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 47
PIC18(L)F2X/4XK22
3.1.3
MULTIPLE FUNCTIONS OF THE
SLEEP COMMAND
The power-managed mode that is invoked with the
SLEEP instruction is determined by the value of the
IDLEN bit at the time the instruction is executed. If
IDLEN = 0, when SLEEP is executed, the device enters
the sleep mode and all clocks stop and minimum power
is consumed. If IDLEN = 1, when SLEEP is executed,
the device enters the IDLE mode and the system clock
continues to supply a clock to the peripherals but is
disconnected from the CPU.
3.2
Run Modes
In the Run modes, clocks to both the core and
peripherals are active. The difference between these
modes is the clock source.
3.2.1
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 2.10 “Two-Speed
Clock Start-up Mode” for details). In this mode, the
device is operated off the oscillator defined by the
FOSC<3:0> bits of the CONFIG1H Configuration
register.
3.2.2
SEC_RUN MODE
In SEC_RUN mode, the CPU and peripherals are
clocked from the secondary external oscillator. This
gives users the option of lower power consumption
while still using a high accuracy clock source.
SEC_RUN mode is entered by setting the SCS<1:0>
bits to ‘01’. When SEC_RUN mode is active, all of the
following are true:
• The device clock source is switched to the SOSC
oscillator (see Figure 3-1)
• The primary oscillator is shut down
• The SOSCRUN bit (OSCCON2<6>) is set
• The OSTS bit (OSCCON2<3>) is cleared
Note:
The secondary external oscillator should
already be running prior to entering
SEC_RUN mode. If the SOSCGO bit or
any of the TxSOSCEN bits are not set
when the SCS<1:0> bits are set to ‘01’,
entry to SEC_RUN mode will not occur
until SOSCGO bit is set and secondary
external oscillator is ready.
SOSCRUN 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 and the
SOSC oscillator continues to run.
3.2.3
RC_RUN MODE
In RC_RUN mode, the CPU and peripherals are
clocked from the internal oscillator block using the
INTOSC multiplexer. In this mode, the primary clock is
shut down. When using the LFINTOSC source, 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. If the
primary clock source is the internal oscillator block –
either LFINTOSC or INTOSC (MFINTOSC or
HFINTOSC) – there are no distinguishable differences
between the PRI_RUN and RC_RUN modes during
execution. Entering or exiting RC_RUN mode,
however, causes a clock switch delay. Therefore, if the
primary clock source is the internal oscillator block,
using RC_RUN mode is not recommended.
This mode is entered by setting the SCS1 bit to ‘1’. To
maintain software compatibility with future devices, it is
recommended that the SCS0 bit also be cleared, even
though the bit is ignored. When the clock source is
switched to the INTOSC multiplexer (see Figure 3-1),
the primary oscillator is shut down and the OSTS bit is
cleared. The IRCF<2:0> bits (OSCCON<6:4>) may be
modified at any time to immediately change the clock
speed.
When the IRCF bits and the INTSRC bit are all clear,
the INTOSC output (HFINTOSC/MFINTOSC) is not
enabled and the HFIOFS and MFIOFS bits will remain
clear. There will be no indication of the current clock
source. The LFINTOSC source is providing the device
clocks.
If the IRCF bits are changed from all clear (thus,
enabling the INTOSC output) or if INTSRC or MFIOSEL
is set, then the HFIOFS or MFIOFS bit is set after the
INTOSC output becomes stable. For details, see
Table 3-2.
Clocks to the device continue while the INTOSC source
stabilizes after an interval of TIOBST.
If the IRCF bits were previously at a non-zero value, or
if INTSRC was set before setting SCS1 and the
INTOSC source was already stable, then the HFIOFS
or MFIOFS bit will remain set.
On transitions from SEC_RUN mode to PRI_RUN
mode, the peripherals and CPU continue to be clocked
from the SOSC oscillator, while the primary clock is
started. When the primary clock becomes ready, a
clock switch back to the primary clock occurs (see
Figure 3-2). When the clock switch is complete, the
DS41412C-page 48
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
On transitions from RC_RUN mode to PRI_RUN mode,
the device continues to be clocked from the INTOSC
multiplexer while the primary clock is started. When the
primary clock becomes ready, a clock switch to the primary clock occurs (see Figure 3-3). When the clock
switch is complete, the HFIOFS or MFIOFS bit is
cleared, 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 LFINTOSC source
will continue to run if either the WDT or the Fail-Safe
Clock Monitor is enabled.
FIGURE 3-1:
TRANSITION TIMING FOR ENTRY TO SEC_RUN MODE
Q1 Q2 Q3 Q4 Q1
Q2
1
SOSCI
2
3
n-1
Q3
Q4
Q1
Q2
Q3
n
Clock Transition(1)
OSC1
CPU
Clock
Peripheral
Clock
Program
Counter
PC
PC + 2
PC + 4
Note 1: Clock transition typically occurs within 2-4 TOSC.
FIGURE 3-2:
TRANSITION TIMING FROM SEC_RUN MODE TO PRI_RUN MODE (HSPLL)
Q1
Q2
Q3
Q4
Q1
Q2 Q3 Q4 Q1 Q2 Q3
SOSC
OSC1
TOST(1)
TPLL(1)
1
PLL Clock
Output
2
n-1 n
Clock
Transition(2)
CPU Clock
Peripheral
Clock
Program
Counter
PC + 2
PC
SCS<1:0> bits Changed
PC + 4
OSTS bit Set
Note1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
2: Clock transition typically occurs within 2-4 TOSC.
TABLE 3-2:
INTERNAL OSCILLATOR FREQUENCY STABILITY BITS
IRCF<2:0>
INTSRC
MFIOSEL
INTOSC Stability Indication
000
0
x
MFIOFS = 0, HFIOFS = 0 LFINTOSC
000
1
0
MFIOFS = 0, HFIOFS = 1 HFINTOSC
000
1
1
MFIOFS = 1, HFIOFS = 0 MFINTOSC
010 or 001
x
0
MFIOFS = 0, HFIOFS = 1 HFINTOSC
010 or 001
x
1
MFIOFS = 1, HFIOFS = 0 MFINTOSC
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 49
PIC18(L)F2X/4XK22
FIGURE 3-3:
TRANSITION TIMING FROM RC_RUN MODE TO PRI_RUN MODE
Q1
Q2
Q3
Q4
Q2 Q3 Q4 Q1 Q2 Q3
Q1
INTOSC
Multiplexer
OSC1
TOST(1)
TPLL(1)
1
PLL Clock
Output
2
n-1 n
Clock
Transition(2)
CPU Clock
Peripheral
Clock
Program
Counter
PC + 2
PC
SCS<1:0> bits Changed
PC + 4
OSTS bit Set
Note1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
2: Clock transition typically occurs within 2-4 TOSC.
DS41412C-page 50
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
3.3
Sleep Mode
3.4
The Power-Managed Sleep mode in the PIC18(L)F2X/
4XK22 devices is identical to the legacy Sleep mode
offered in all other PIC® microcontroller devices. It is
entered by clearing the IDLEN bit of the OSCCON
register and executing the SLEEP instruction. This shuts
down the selected oscillator (Figure 3-4) and 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 by 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 either Run or Idle 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 LFINTOSC source
will continue to operate. If the SOSC oscillator is
enabled, it will also continue to run.
If the WDT is selected, the LFINTOSC source will continue to operate. If the SOSC 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 3-5), or it will be clocked
from the internal oscillator block if either the Two-Speed
Start-up or the Fail-Safe Clock Monitor are enabled
(see Section 24.0 “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 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 3-4:
TRANSITION TIMING FOR ENTRY TO SLEEP MODE
Q1 Q2 Q3 Q4 Q1
OSC1
CPU
Clock
Peripheral
Clock
Sleep
Program
Counter
PC
 2010 Microchip Technology Inc.
PC + 2
Preliminary
DS41412C-page 51
PIC18(L)F2X/4XK22
FIGURE 3-5:
TRANSITION TIMING FOR WAKE FROM SLEEP (HSPLL)
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Q1
OSC1
TOST(1)
PLL Clock
Output
TPLL(1)
CPU Clock
Peripheral
Clock
Program
Counter
PC
Wake Event
PC + 2
PC + 4
PC + 6
OSTS bit set
Note1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale.
3.4.1
3.4.2
PRI_IDLE MODE
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 clear the SCS bits and execute SLEEP.
Although the CPU is disabled, the peripherals continue
to be clocked from the primary clock source specified
by the FOSC<3:0> Configuration bits. The OSTS bit
remains set (see Figure 3-6).
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 wakeup, the OSTS bit remains set. The IDLEN and SCS bits
are not affected by the wake-up (see Figure 3-7).
FIGURE 3-6:
SEC_IDLE MODE
In SEC_IDLE mode, the CPU is disabled but the
peripherals continue to be clocked from the SOSC
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 the IDLEN bit
first, then set the SCS<1:0> bits to ‘01’ and execute
SLEEP. When the clock source is switched to the SOSC
oscillator, the primary oscillator is shut down, the OSTS
bit is cleared and the SOSCRUN bit is set.
When a wake event occurs, the peripherals continue to
be clocked from the SOSC oscillator. After an interval
of TCSD following the wake event, the CPU begins executing code being clocked by the SOSC oscillator. The
IDLEN and SCS bits are not affected by the wake-up;
the SOSC oscillator continues to run (see Figure 3-7).
Note:
The SOSC oscillator should already be
running prior to entering SEC_IDLE mode.
At least one of the secondary oscillator
enable bits (SOSCGO, T1SOSCEN,
T3SOSCEN or T5SOSCEN) must be set
when the SLEEP instruction is executed.
Otherwise, the main system clock will continue to operate in the previously selected
mode and the corresponding IDLE mode
will be entered (i.e., PRI_IDLE or
RC_IDLE).
TRANSITION TIMING FOR ENTRY TO IDLE MODE
Q1
Q3
Q2
Q4
Q1
OSC1
CPU Clock
Peripheral
Clock
Program
Counter
DS41412C-page 52
PC
PC + 2
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 3-7:
TRANSITION TIMING FOR WAKE FROM IDLE TO RUN MODE
Q1
Q2
Q3
Q4
OSC1
TCSD
CPU Clock
Peripheral
Clock
Program
Counter
PC
Wake Event
3.4.3
RC_IDLE MODE
In RC_IDLE mode, the CPU is disabled but the peripherals continue to be clocked from the internal oscillator
block from the HFINTOSC multiplexer output. 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 set
the SCS1 bit and execute SLEEP. It is recommended
that SCS0 also be cleared, although its value is
ignored, to maintain software compatibility with future
devices. The HFINTOSC multiplexer may be used to
select a higher clock frequency by modifying the IRCF
bits before executing the SLEEP instruction. When the
clock source is switched to the HFINTOSC multiplexer,
the primary oscillator is shut down and the OSTS bit is
cleared.
Clocks to the peripherals continue while the
HFINTOSC source stabilizes. The HFIOFS and
MFIOFS bits will remain set if the IRCF bits were
previously set at a non-zero value or if INTSRC was set
before the SLEEP instruction was executed and the
HFINTOSC source was already stable. If the IRCF bits
and INTSRC are all clear, the HFINTOSC output will
not be enabled, the HFIOFS and MFIOFS bits will
remain clear and there will be no indication of the
current clock source.
When a wake event occurs, the peripherals continue to
be clocked from the HFINTOSC multiplexer output.
After a delay of TCSD following the wake event, the CPU
begins executing code being clocked by the
HFINTOSC multiplexer. The IDLEN and SCS bits are
not affected by the wake-up. The LFINTOSC source
will continue to run if either the WDT or the Fail-Safe
Clock Monitor is enabled.
If the IRCF bits are set to any non-zero value, or either
the INTSRC or MFIOSEL bits are set, the HFINTOSC
output is enabled. Either the HFIOFS or the MFIOFS
bits become set, after the HFINTOSC output stabilizes
after an interval of TIOBST. For information on the
HFIOFS and MFIOFS bits, see Table 3-2.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 53
PIC18(L)F2X/4XK22
3.5
Exiting Idle and Sleep Modes
3.5.2
An exit from Sleep mode or any of the Idle modes is
triggered by any one of the following:
• an interrupt
• a Reset
• a Watchdog 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 (see Section 3.2 “Run Modes”, Section 3.3
“Sleep Mode” and Section 3.4 “Idle Modes”).
3.5.1
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.
The instruction immediately following the SLEEP
instruction is executed on all exits by interrupt from Idle
or Sleep modes. Code execution then branches to the
interrupt vector if the GIE/GIEH bit of the INTCON
register is set, otherwise code execution continues
without branching (see Section 9.0 “Interrupts”).
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.
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 3.2 “Run
Modes” and Section 3.3 “Sleep Mode”). If the device
is executing code (all Run modes), the time-out will
result in a WDT Reset (see Section 24.2 “Watchdog
Timer (WDT)”).
The WDT timer and postscaler are cleared by any one
of the following:
• executing a SLEEP instruction
• executing a CLRWDT instruction
• the loss of the currently selected clock source
when the Fail-Safe Clock Monitor is enabled
• modifying the IRCF bits in the OSCCON register
when the internal oscillator block is the device
clock source
3.5.3
EXIT BY RESET
Exiting Sleep and Idle modes by Reset causes code
execution to restart at address 0. See Section 4.0
“Reset” for more details.
The exit delay time from Reset to the start of code
execution depends on both the clock sources before
and after the wake-up and the type of oscillator. Exit
delays are summarized in Table 3-3.
3.5.4
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 not any of the LP, XT,
HS or HSPLL modes.
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 (RC, EC, INTOSC,
and INTOSCIO modes). 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.
DS41412C-page 54
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 3-3:
EXIT DELAY ON WAKE-UP BY RESET FROM SLEEP MODE OR ANY IDLE MODE
(BY CLOCK SOURCES)
Clock Source
before Wake-up
Clock Source
after Wake-up
Exit Delay
Clock Ready Status
Bit (OSCCON)
LP, XT, HS
Primary Device Clock
(PRI_IDLE mode)
HSPLL
EC, RC
TCSD(1)
HFINTOSC(2)
T1OSC or LFINTOSC(1)
HFINTOSC(2)
None
(Sleep mode)
2:
3:
4:
IOSF
LP, XT, HS
TOST(3)
HSPLL
TOST + tPLL(3)
EC, RC
TCSD(1)
HFINTOSC(1)
TIOBST(4)
LP, XT, HS
TOST(4)
HSPLL
TOST + tPLL(3)
EC, RC
TCSD(1)
OSTS
IOSF
OSTS
HFINTOSC(1)
None
LP, XT, HS
TOST(3)
HSPLL
TOST + tPLL(3)
OSTS
EC, RC
TCSD(1)
TIOBST(4)
IOSF
HFINTOSC(1)
Note 1:
OSTS
IOSF
TCSD is a required delay when waking from Sleep and all Idle modes and runs concurrently with any other
required delays (see Section 3.4 “Idle Modes”). On Reset, HFINTOSC defaults to 1 MHz.
Includes both the HFINTOSC 16 MHz source and postscaler derived frequencies.
TOST is the Oscillator Start-up Timer. tPLL is the PLL Lock-out Timer.
Execution continues during the HFINTOSC stabilization period, TIOBST.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 55
PIC18(L)F2X/4XK22
3.6
Selective Peripheral Module
Control
Idle mode allows users to substantially reduce power
consumption by stopping the CPU clock. Even so,
peripheral modules still remain clocked, and thus, consume power. There may be cases where the application needs what IDLE mode does not provide: the
allocation of power resources to the CPU processing
with minimal power consumption from the peripherals.
PIC18(L)F2X/4XK22 family devices address this
requirement by allowing peripheral modules to be
selectively disabled, reducing or eliminating their
power consumption. This can be done with control bits
in the Peripheral Module Disable (PMD) registers.
These bits generically named XXXMD are located in
control registers PMD0, PMD1 or PMD2.
REGISTER 3-1:
Setting the PMD bit for a module disables all clock
sources to that module, reducing its power
consumption to an absolute minimum. In this state, the
control and STATUS registers associated with the
peripheral are also disabled, so writes to these
registers have no effect and read values are invalid.
PMD0: PERIPHERAL MODULE DISABLE REGISTER 0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
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
UART2MD: UART2 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 6
UART1MD: UART1 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 5
TMR6MD: Timer6 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 4
TMR5MD: Timer5 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 3
TMR4MD: Timer4 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 2
TMR3MD: Timer3 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 1
TMR2MD: Timer2 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 0
TMR1MD: Timer1 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
DS41412C-page 56
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 3-2:
PMD1: PERIPHERAL MODULE DISABLE REGISTER 1
R/W-0
R/W-0
MSSP2MD
MSSP1MD
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
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
MSSP2MD: MSSP2 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 6
MSSP1MD: MSSP1 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 5
Unimplemented: Read as ‘0’
bit 4
CCP5MD: CCP5 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 3
CCP4MD: CCP4 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 2
CCP3MD: CCP3 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 1
CCP2MD: CCP2 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 0
CCP1MD: CCP1 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 57
PIC18(L)F2X/4XK22
REGISTER 3-3:
PMD2: PERIPHERAL MODULE DISABLE REGISTER 2
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
—
CTMUMD
CMP2MD
CMP1MD
ADCMD
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 7-4
Unimplemented: Read as ‘0’
bit 3
CTMUMD: CTMU Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 2
CMP2MD: Comparator C2 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 1
CMP1MD: Comparator C1 Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
bit 0
ADCMD: ADC Peripheral Module Disable Control bit
1 = Module is disabled, Clock Source is disconnected, module does not draw digital power
0 = Module is enabled, Clock Source is connected, module draws digital power
DS41412C-page 58
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
4.0
RESET
The PIC18(L)F2X/4XK22 devices differentiate between
various kinds of Reset:
a)
b)
c)
d)
e)
f)
g)
h)
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during power-managed modes
Watchdog Timer (WDT) Reset (during
execution)
Programmable Brown-out Reset (BOR)
RESET Instruction
Stack Full Reset
Stack Underflow Reset
4.1
RCON Register
Device Reset events are tracked through the RCON
register (Register 4-1). The lower five bits of the
register indicate that a specific Reset event has
occurred. In most cases, these bits can only be cleared
by the event and must be set 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 4.6 “Reset State of Registers”.
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 5.1.2.4 “Stack Full and Underflow Resets”.
WDT Resets are covered in Section 24.2 “Watchdog
Timer (WDT)”.
FIGURE 4-1:
A simplified block diagram of the On-Chip Reset Circuit
is shown in Figure 4-1.
The RCON register also has control bits for setting
interrupt priority (IPEN) and software control of the
BOR (SBOREN). Interrupt priority is discussed in
Section 9.0 “Interrupts”. BOR is covered in
Section 4.4 “Brown-out Reset (BOR)”.
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
RESET
Instruction
Stack Full/Underflow Reset
Stack
Pointer
External Reset
MCLRE
MCLR
( )_IDLE
Sleep
WDT
Time-out
VDD
Detect
POR
VDD
Brown-out
Reset
S
BOREN
OST/PWRT
OST(2) 1024 Cycles
Chip_Reset
10-bit Ripple Counter
R
OSC1
32 s
LFINTOSC
Q
PWRT(2) 65.5 ms
11-bit Ripple Counter
Enable PWRT
Enable OST(1)
Note 1:
2:
See Table for time-out situations.
PWRT and OST counters are reset by POR and BOR. See Sections 4.3 and 4.4.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 59
PIC18(L)F2X/4XK22
REGISTER 4-1:
R/W-0/0
IPEN
RCON: RESET CONTROL REGISTER
R/W-q/u
SBOREN
(1)
U-0
R/W-1/q
—
RI
R-1/q
R-1/q
TO
R/W-q/u
(2)
PD
POR
bit 7
R/W-0/q
BOR
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
-n/n = Value at POR and BOR/Value at all other Resets
x = Bit is unknown
u = unchanged
q = depends on condition
bit 7
IPEN: Interrupt Priority Enable bit
1 = Enable priority levels on interrupts
0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode)
bit 6
SBOREN: BOR Software Enable bit(1)
If BOREN<1:0> = 01:
1 = BOR is enabled
0 = BOR is disabled
If BOREN<1:0> = 00, 10 or 11:
Bit is disabled and read as ‘0’.
bit 5
Unimplemented: Read as ‘0’
bit 4
RI: RESET Instruction Flag bit
1 = The RESET instruction was not executed (set by firmware or Power-on Reset)
0 = The RESET instruction was executed causing a device Reset (must be set in firmware after a
code-executed 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(2)
1 = No Power-on Reset occurred
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(3)
1 = A Brown-out Reset has not occurred (set by firmware only)
0 = A Brown-out Reset occurred (must be set by firmware after a POR or Brown-out Reset occurs)
Note 1:
2:
3:
When CONFIG2L[2:1] = 01, then the SBOREN Reset state is ‘1’; otherwise, it is ‘0’.
The actual Reset value of POR is determined by the type of device Reset. See the notes following this
register and Section 4.6 “Reset State of Registers” for additional information.
See Table .
Note 1: Brown-out Reset is indicated when BOR is ‘0’ and POR is ‘1’ (assuming that both POR and BOR were set
to ‘1’ by firmware immediately after POR).
2: 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.
DS41412C-page 60
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
4.2
Master Clear (MCLR)
FIGURE 4-2:
The MCLR pin provides a method for triggering an
external Reset of the device. A Reset is generated by
holding the pin low. These devices have a noise filter in
the MCLR Reset path which detects and ignores small
pulses. An internal weak pull-up is enabled when the
pin is configured as the MCLR input.
In PIC18(L)F2X/4XK22 devices, the MCLR input can
be disabled with the MCLRE Configuration bit. When
MCLR is disabled, the pin becomes a digital input. See
Section 10.6 “PORTE Registers” for more
information.
4.3
VDD
VDD
D
The MCLR pin is not driven low by any internal Resets,
including the WDT.
EXTERNAL POWER-ON
RESET CIRCUIT (FOR
SLOW VDD POWER-UP)
PIC® MCU
R
R1
MCLR
C
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:
15 k < R < 40 k is recommended to make
sure that the voltage drop across R does not
violate the device’s electrical specification.
3:
R1  1 k will limit any current flowing into
MCLR from external capacitor C, in the event
of MCLR/VPP pin breakdown, due to
Electrostatic Discharge (ESD) or Electrical
Overstress (EOS).
Power-on Reset (POR)
A Power-on Reset pulse 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.
To take advantage of the POR circuitry either leave the
pin floating, or tie the MCLR pin through a resistor 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. For a slow rise
time, see Figure 4-2.
When the device starts normal operation (i.e., exits the
Reset condition), device operating parameters (voltage, frequency, temperature, etc.) must be met to
ensure proper operation. If these conditions are not
met, the device must be held in Reset until the operating conditions are met.
POR events are captured by the POR bit of the RCON
register. The state of the bit is set to ‘0’ whenever a
POR 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 must manually set
the bit to ‘1’ by software following any POR.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 61
PIC18(L)F2X/4XK22
4.4
Brown-out Reset (BOR)
4.4.2
PIC18(L)F2X/4XK22 devices implement a BOR circuit
that provides the user with a number of configuration and
power-saving options. The BOR is controlled by the
BORV<1:0> and BOREN<1:0> bits of the CONFIG2L
Configuration register. There are a total of four BOR
configurations which are summarized in Table 4-1.
The BOR threshold is set by the BORV<1:0> bits. If
BOR is enabled (any values of BOREN<1:0>, except
‘00’), any drop of VDD below VBOR for greater than
TBOR 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.
If the Power-up Timer is enabled, it will be invoked after
VDD rises above VBOR; it then will keep the chip in
Reset for an additional time delay, TPWRT. 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.
BOR and the Power-on Timer (PWRT) are
independently configured. Enabling BOR Reset does
not automatically enable the PWRT.
The BOR circuit has an output that feeds into the POR
circuit and rearms the POR within the operating range
of the BOR. This early rearming of the POR ensures
that the device will remain in Reset in the event that VDD
falls below the operating range of the BOR circuitry.
4.4.1
DETECTING BOR
When BOR is enabled, the BOR bit always resets to ‘0’
on any BOR or POR event. This makes it difficult to
determine if a BOR 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 and BOR bits are reset to
‘1’ by software immediately after any POR event. If
BOR is ‘0’ while POR is ‘1’, it can be reliably assumed
that a BOR event has occurred.
DS41412C-page 62
SOFTWARE ENABLED BOR
When BOREN<1:0> = 01, the BOR can be enabled or
disabled by the user in software. This is done with the
SBOREN control bit of the RCON register. Setting
SBOREN enables the BOR to function as previously
described. Clearing SBOREN disables the BOR
entirely. The SBOREN bit operates only in this mode;
otherwise it is read as ‘0’.
Placing the BOR under software control gives the user
the additional flexibility of tailoring the application to the
environment without having to reprogram the device to
change BOR configuration. It also allows the user to
tailor device power consumption in software by
eliminating the incremental current that the BOR
consumes. While the BOR current is typically very small,
it may have some impact in low-power applications.
Note:
4.4.3
Even when BOR is under software control,
the BOR Reset voltage level is still set by
the BORV<1:0> Configuration bits. It
cannot be changed by software.
DISABLING BOR IN SLEEP MODE
When BOREN<1:0> = 10, the BOR remains under
hardware control and operates as previously
described. Whenever the device enters Sleep mode,
however, the BOR is automatically disabled. When the
device returns to any other operating mode, BOR is
automatically re-enabled.
This mode allows for applications to recover from
brown-out situations, while actively executing code,
when the device requires BOR protection the most. At
the same time, it saves additional power in Sleep mode
by eliminating the small incremental BOR current.
4.4.4
MINIMUM BOR ENABLE TIME
Enabling the BOR also enables the Fixed Voltage
Reference (FVR) when no other peripheral requiring the
FVR is active. The BOR becomes active only after the
FVR stabilizes. Therefore, to ensure BOR protection,
the FVR settling time must be considered when
enabling the BOR in software or when the BOR is
automatically enabled after waking from Sleep. If the
BOR is disabled, in software or by reentering Sleep
before the FVR stabilizes, the BOR circuit will not sense
a BOR condition. The FVRST bit of the VREFCON0
register can be used to determine FVR stability.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 4-1:
BOR CONFIGURATIONS
BOR Configuration
BOREN1
BOREN0
Status of
SBOREN
(RCON<6>)
0
0
Unavailable
0
1
Available
1
0
Unavailable
BOR enabled by hardware in Run and Idle modes, disabled during
Sleep mode.
1
1
Unavailable
BOR enabled by hardware; must be disabled by reprogramming the Configuration bits.
4.5
BOR Operation
BOR disabled; must be enabled by reprogramming the Configuration bits.
BOR enabled by software; operation controlled by SBOREN.
Device Reset Timers
4.5.3
PIC18(L)F2X/4XK22 devices incorporate three
separate on-chip timers that help regulate the Poweron Reset process. Their main function is to ensure that
the device clock is stable before code is executed.
These timers are:
• Power-up Timer (PWRT)
• Oscillator Start-up Timer (OST)
• PLL Lock Time-out
4.5.1
With the PLL enabled, the time-out sequence following a
Power-on Reset is slightly different from other oscillator
modes. A separate timer is used to provide a fixed timeout that is sufficient for the PLL to lock to the main
oscillator frequency. This PLL lock time-out (TPLL) is
typically 2 ms and follows the oscillator start-up time-out.
4.5.4
TIME-OUT SEQUENCE
On power-up, the time-out sequence is as follows:
1.
POWER-UP TIMER (PWRT)
The Power-up Timer (PWRT) of PIC18(L)F2X/4XK22
devices is an 11-bit counter which uses the
LFINTOSC source as the clock input. This yields an
approximate time interval of 2048 x 32 s = 65.6 ms.
While the PWRT is counting, the device is held in
Reset.
The power-up time delay depends on the LFINTOSC
clock and will vary from chip-to-chip due to temperature
and process variation.
The PWRT is enabled by clearing the PWRTEN
Configuration bit.
4.5.2
PLL LOCK TIME-OUT
OSCILLATOR START-UP TIMER
(OST)
The Oscillator Start-up Timer (OST) provides a 1024
oscillator cycle (from OSC1 input) delay after the
PWRT delay is over. This ensures that the crystal
oscillator or resonator has started and stabilized.
2.
After the POR pulse has cleared, PWRT time-out
is invoked (if enabled).
Then, the OST is activated.
The total time-out will vary based on oscillator
configuration and the status of the PWRT. Figure 4-3,
Figure 4-4, Figure 4-5, Figure 4-6 and Figure 4-7 all
depict time-out sequences on power-up, with the
Power-up Timer enabled and the device operating in
HS Oscillator mode. Figures 4-3 through 4-6 also
apply to devices operating in XT or LP modes. For
devices in RC mode and with the PWRT disabled, on
the other hand, there will be no time-out at all.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, all time-outs will expire, after
which, bringing MCLR high will allow program
execution to begin immediately (Figure 4-5). This is
useful for testing purposes or to synchronize more than
one PIC® MCU device operating in parallel.
The OST time-out is invoked only for XT, LP and HS
modes and only on Power-on Reset, or on exit from all
power-managed modes that stop the external oscillator.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 63
PIC18(L)F2X/4XK22
TABLE 4-2:
TIME-OUT IN VARIOUS SITUATIONS
Oscillator
Configuration
HSPLL
Power-up(2) and Brown-out
PWRTEN = 1
Exit from
Power-Managed Mode
1024 TOSC + 2 ms(2)
1024 TOSC + 2 ms(2)
PWRTEN = 0
66 ms
(1)
+ 1024 TOSC + 2
ms(2)
66 ms(1) + 1024 TOSC
HS, XT, LP
1024 TOSC
1024 TOSC
EC, ECIO
(1)
66 ms
—
—
RC, RCIO
66 ms(1)
—
—
ms(1)
—
—
INTIO1, INTIO2
66
Note 1: 66 ms (65.5 ms) is the nominal Power-up Timer (PWRT) delay.
2: 2 ms is the nominal time required for the PLL to lock.
FIGURE 4-3:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD, VDD RISE < TPWRT)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 4-4:
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
DS41412C-page 64
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 4-5:
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 4-6:
SLOW RISE TIME (MCLR TIED TO VDD, VDD RISE > TPWRT)
5V
VDD
0V
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 65
PIC18(L)F2X/4XK22
FIGURE 4-7:
TIME-OUT SEQUENCE ON POR W/PLL ENABLED (MCLR TIED TO VDD)
VDD
MCLR
INTERNAL POR
TPWRT
PWRT TIME-OUT
TOST
OST TIME-OUT
TPLL
PLL TIME-OUT
INTERNAL RESET
Note:
TOST = 1024 clock cycles.
TPLL  2 ms max. First three stages of the PWRT timer.
DS41412C-page 66
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
4.6
Reset State of Registers
Table 5-2 describes the Reset states for all of the
Special Function Registers. The table identifies
differences between Power-On Reset (POR)/BrownOut Reset (BOR) and all other Resets, (i.e., Master
Clear, WDT Resets, STKFUL, STKUNF, etc.).
Additionally, the table identifies register bits that are
changed when the device receives a wake-up from
WDT or other interrupts.
Some registers are unaffected by a Reset. Their status
is unknown on POR and unchanged by all other
Resets. All other registers are forced to a “Reset state”
depending on the type of Reset that occurred.
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, RI, TO,
PD, POR and BOR, are set or cleared differently in
different Reset situations, as indicated in Table 4-3.
These bits are used by software to determine the
nature of the Reset.
TABLE 4-3:
STATUS BITS, THEIR SIGNIFICANCE AND THE INITIALIZATION CONDITION
FOR RCON REGISTER
Program
Counter
Condition
RCON Register
SBOREN
RI
TO
PD
STKPTR Register
POR BOR STKFUL
STKUNF
Power-on Reset
0000h
1
1
1
1
0
0
0
0
RESET Instruction
0000h
u(2)
0
u
u
u
u
u
u
0000h
u(2)
1
1
1
u
0
u
u
MCLR during Power-Managed
Run Modes
0000h
u(2)
u
1
u
u
u
u
u
MCLR during Power-Managed
Idle Modes and Sleep Mode
0000h
u(2)
u
1
0
u
u
u
u
WDT Time-out during Full Power
or Power-Managed Run Mode
0000h
u(2)
u
0
u
u
u
u
u
MCLR during Full Power
Execution
0000h
u(2)
u
u
u
u
u
u
u
Stack Full Reset (STVREN = 1)
0000h
u(2)
u
u
u
u
u
1
u
Stack Underflow Reset
(STVREN = 1)
0000h
(2)
u
u
u
u
u
u
u
1
Stack Underflow Error (not an
actual Reset, STVREN = 0)
0000h
u(2)
u
u
u
u
u
u
1
WDT Time-out during
Power-Managed Idle or Sleep
Modes
PC + 2
u(2)
u
0
0
u
u
u
u
PC + 2(1)
u(2)
u
u
0
u
u
u
u
Brown-out Reset
Interrupt Exit from
Power-Managed Modes
Legend: u = unchanged
Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bits are set, the PC is loaded with the
interrupt vector (008h or 0018h).
2: Reset state is ‘1’ for SBOREN and unchanged for all other Resets when software BOR is enabled
(BOREN<1:0> Configuration bits = 01). Otherwise, the Reset state is ‘0’.
TABLE 4-4:
Name
RCON
STKPTR
REGISTERS ASSOCIATED WITH RESETS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
IPEN
SBOREN
—
RI
TO
PD
POR
BOR
60
STKFUL
STKUNF
—
STKPTR<4:0>
72
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for Resets.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 67
PIC18(L)F2X/4XK22
TABLE 4-5:
CONFIGURATION REGISTERS ASSOCIATED WITH RESETS
Name
Bit 7
Bit 6
Bit 5
CONFIG2L
—
—
—
CONFIG2H
—
—
Bit 4
Bit 3
BORV<1:0>
Bit 2
BOREN<1:0>
WDPS<3:0>
CONFIG3H
MCLRE
—
P2BMX
T3CMX
CONFIG4L
DEBUG
XINST
—
—
Bit 0
Register
on Page
PWRTEN
352
WDTEN<1:0>
HFOFST CCP3MX
—
Bit 1
LVP
353
PBADEN
CCP2MX
354
—
STRVEN
355
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for Resets.
DS41412C-page 68
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
5.0
MEMORY ORGANIZATION
5.1
There are three types of memory in PIC18 Enhanced
microcontroller devices:
• Program Memory
• Data RAM
• Data EEPROM
As Harvard architecture devices, the data and program
memories use separate buses; this allows for
concurrent access of the two memory spaces. The data
EEPROM, for practical purposes, can be regarded as
a peripheral device, since it is addressed and accessed
through a set of control registers.
Additional detailed information on the operation of the
Flash program memory is provided in Section 6.0
“Flash Program Memory”. Data EEPROM is
discussed separately in Section 7.0 “Data EEPROM
Memory”.
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).
This family of devices contain the following:
• PIC18(L)F23K22, PIC18(L)F43K22: 8 Kbytes of
Flash Memory, up to 4,096 single-word instructions
• PIC18(L)F24K22, PIC18(L)F44K22: 16 Kbytes of
Flash Memory, up to 8,192 single-word instructions
• PIC18(L)F25K22, PIC18(L)F45K22: 32 Kbytes of
Flash Memory, up to 16,384 single-word instructions
• PIC18(L)F26K22, PIC18(L)F46K22: 64 Kbytes of
Flash Memory, up to 37,768 single-word
instructions
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 PIC18(L)F2X/4XK22
devices is shown in Figure 5-1. Memory block details
are shown in Figure 20-2.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 69
PIC18(L)F2X/4XK22
FIGURE 5-1:
PROGRAM MEMORY MAP AND STACK FOR PIC18(L)F2X/4XK22 DEVICES
PC<20:0>
21
CALL,RCALL,RETURN
RETFIE,RETLW
Stack Level 1



Stack Level 31
2000h
0000h
High Priority Interrupt Vector
0008h
Low Priority Interrupt Vector
0018h
On-Chip
Program Memory
3FFFh
4000h
PIC18(L)F23K22
PIC18(L)F43K22
On-Chip
Program Memory
User Memory Space
On-Chip
Program Memory
1FFFh
Reset Vector
On-Chip
Program Memory
PIC18(L)F24K22
PIC18(L)F44K22
7FFFh
8000h
PIC18(L)F25K22
PIC18(L)F45K22
Read ‘0’
Read ‘0’
Read ‘0’
FFFFh
10000h
PIC18(L)F26K22
PIC18(L)F46K22
Read ‘0’
5.1.1
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 5.1.4.1 “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.
DS41412C-page 70
1FFFFFh
200000h
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.
5.1.2
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 a RETFIE instruction. PCLATU and PCLATH
are not affected by any of the RETURN or CALL
instructions.
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 (TOS) Special File Registers. Data can also be
pushed to, or popped from the stack, using these
registers.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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.
FIGURE 5-2:
5.1.2.1
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 5-2). 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 (GIE)
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
STKPTR<4:0>
00010
TOSL
34h
Top-of-Stack
5.1.2.2
Return Stack Pointer (STKPTR)
The STKPTR register (Register 5-1) contains the Stack
Pointer value, the STKFUL (stack full) 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.
001A34h
000D58h
00011
00010
00001
00000
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 STKPTR will remain at 31.
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:
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 24.1 “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.
 2010 Microchip Technology Inc.
Stack Pointer
Preliminary
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.
DS41412C-page 71
PIC18(L)F2X/4XK22
5.1.2.3
PUSH and POP Instructions
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.
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.
REGISTER 5-1:
R/C-0
(1)
STKFUL
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
U-0
STKUNF(1)
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
STKPTR<4:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented
C = Clearable only bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
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
STKPTR<4:0>: Stack Pointer Location bits
Note 1:
5.1.2.4
Bit 7 and bit 6 are cleared by user software or by a POR.
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.
5.1.3
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.
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 by software during a low priority interrupt.
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 5-1 shows a source code example that uses
the fast register stack during a subroutine call and
return.
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
DS41412C-page 72
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
EXAMPLE 5-1:
FAST REGISTER STACK
CODE EXAMPLE
CALL SUB1, FAST
;STATUS, WREG, BSR
;SAVED IN FAST REGISTER
;STACK




RETURN, FAST
SUB1
5.1.4
;RESTORE VALUES SAVED
;IN FAST REGISTER STACK
5.1.4.2
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 6.1 “Table Reads and Table
Writes”.
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
5.1.4.1
Computed GOTO
A computed GOTO is accomplished by adding an offset
to the program counter. An example is shown in
Example 5-2.
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.
The offset value (in WREG) specifies the number of
bytes that the program counter should advance and
should be multiples of 2 (LSb = 0).
In this method, only one data byte may be stored in
each instruction location and room on the return
address stack is required.
EXAMPLE 5-2:
ORG
TABLE
MOVF
CALL
nn00h
ADDWF
RETLW
RETLW
RETLW
.
.
.
COMPUTED GOTO USING
AN OFFSET VALUE
OFFSET, W
TABLE
PCL
nnh
nnh
nnh
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 73
PIC18(L)F2X/4XK22
5.2
PIC18 Instruction Cycle
5.2.1
5.2.2
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 5-3).
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 5-3.
FIGURE 5-3:
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/CLKOUT
(RC mode)
Execute INST (PC – 2)
Fetch INST (PC)
EXAMPLE 5-3:
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
Fetch 2
TCY2
TCY3
TCY4
TCY5
Execute 2
Fetch 3
Execute 3
Fetch 4
PORTA, BIT3 (Forced NOP)
Flush (NOP)
Fetch SUB_1 Execute SUB_1
5. Instruction @ address 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.
DS41412C-page 74
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
5.2.3
INSTRUCTIONS IN PROGRAM
MEMORY
The program memory is addressed in bytes.
Instructions are stored as either 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 5.1.1 “Program Counter”).
Figure 5-4 shows an example of how instruction words
are stored in the program memory.
FIGURE 5-4:
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 5-4 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 25.0 “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 
5.2.4
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 instruction 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
EXAMPLE 5-4:
Word Address

000000h
000002h
000004h
000006h
000008h
00000Ah
00000Ch
00000Eh
000010h
000012h
000014h
and used by 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 5-4 shows how this works.
Note:
See Section 5.6 “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
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 75
PIC18(L)F2X/4XK22
5.3
Note:
Data Memory Organization
5.3.1
The operation of some aspects of data
memory are changed when the PIC18
extended instruction set is enabled. See
Section 5.5 “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. Figures 5-5
through 5-7 show the data memory organization for the
PIC18(L)F2X/4XK22 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 Bank
Select Register (BSR). Section 5.3.2 “Access Bank”
provides a detailed description of the Access RAM.
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 Figures 5-5 through 5-7.
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 maps in
Figures 5-5 through 5-7 indicate 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.
DS41412C-page 76
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 5-5:
DATA MEMORY MAP FOR PIC18(L)F23K22 AND PIC18(L)F43K22 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
Bank 3
Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
Bank 9
FFh
00h
1FFh
200h
FFh
00h
2FFh
300h
FFh
00h
3FFh
400h
FFh
00h
4FFh
500h
FFh
00h
5FFh
600h
FFh
00h
6FFh
700h
FFh
00h
7FFh
800h
FFh
00h
Unused
Read 00h
9FFh
A00h
FFh
00h
AFFh
B00h
FFh
00h
BFFh
C00h
FFh
Bank 13 00h
CFFh
D00h
FFh
00h
DFFh
E00h
FFh
00h
EFFh
F00h
F37h
F38h
F5Fh
F60h
Bank 11
Bank 12
Bank 14
Bank 15
Unused
SFR(1)
SFR
FFh
 2010 Microchip Technology Inc.
The second 160 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
5Fh
Access RAM High 60h
(SFRs)
FFh
8FFh
900h
FFh
00h
Bank 10
The first 96 bytes are
general purpose RAM
(from Bank 0).
GPR
Bank 1
Bank 2
The BSR is ignored and the
Access Bank is used.
000h
05Fh
060h
0FFh
100h
FFFh
Preliminary
Note 1:
Addresses F38h through F5Fh are
also used by SFRs, but are not
part of the Access RAM. Users
must always use the complete
address or load the proper BSR
value to access these registers.
DS41412C-page 77
PIC18(L)F2X/4XK22
FIGURE 5-6:
DATA MEMORY MAP FOR PIC18(L)F24K22 AND PIC18(L)F44K22 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
Bank 3
Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
Bank 9
GPR
FFh
00h
2FFh
300h
FFh
00h
3FFh
400h
FFh
00h
4FFh
500h
FFh
00h
5FFh
600h
FFh
00h
6FFh
700h
FFh
00h
Unused
Read 00h
AFFh
B00h
FFh
00h
BFFh
C00h
FFh
Bank 13 00h
CFFh
D00h
FFh
00h
DFFh
E00h
Bank 14
FFh
00h
Bank 15
Unused
SFR(1)
EFFh
F00h
F37h
F38h
F5Fh
F60h
SFR
FFh
DS41412C-page 78
The BSR specifies the Bank
used by the instruction.
Access Bank
Access RAM Low
00h
5Fh
Access RAM High 60h
(SFRs)
FFh
8FFh
900h
FFh
00h
Bank 12
When ‘a’ = 1:
7FFh
800h
FFh
00h
9FFh
A00h
Bank 11
The second 160 bytes are
Special Function Registers
(from Bank 15).
1FFh
200h
FFh
00h
FFh
00h
Bank 10
The first 96 bytes are
general purpose RAM
(from Bank 0).
GPR
Bank 1
Bank 2
The BSR is ignored and the
Access Bank is used.
000h
05Fh
060h
0FFh
100h
FFFh
Preliminary
Note 1:
Addresses F38h through F5Fh are
also used by SFRs, but are not
part of the Access RAM. Users
must always use the complete
address or load the proper BSR
value to access these registers.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 5-7:
DATA MEMORY MAP FOR PIC18(L)F25K22 AND PIC18(L)F45K22 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
Bank 3
Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
Bank 9
Bank 10
GPR
FFh
00h
2FFh
300h
GPR
4FFh
500h
FFh
00h
GPR
FFh
00h
5FFh
600h
FFh
00h
6FFh
700h
FFh
00h
7FFh
800h
FFh
00h
8FFh
900h
FFh
00h
Unused
Read 00h
FFh
Bank 13 00h
CFFh
D00h
FFh
00h
DFFh
E00h
FFh
00h
Bank 15
Unused
SFR(1)
EFFh
F00h
F37h
F38h
F5Fh
F60h
SFR
FFh
Access Bank
Access RAM Low
00h
5Fh
Access RAM High 60h
(SFRs)
FFh
9FFh
A00h
BFFh
C00h
 2010 Microchip Technology Inc.
The BSR specifies the Bank
used by the instruction.
3FFh
400h
FFh
00h
FFh
00h
Bank 14
When ‘a’ = 1:
GPR
AFFh
B00h
Bank 12
The second 160 bytes are
Special Function Registers
(from Bank 15).
1FFh
200h
FFh
00h
FFh
00h
Bank 11
The first 96 bytes are
general purpose RAM
(from Bank 0).
GPR
Bank 1
Bank 2
The BSR is ignored and the
Access Bank is used.
000h
05Fh
060h
0FFh
100h
FFFh
Preliminary
Note 1:
Addresses F38h through F5Fh are
also used by SFRs, but are not
part of the Access RAM. Users
must always use the complete
address or load the proper BSR
value to access these registers.
DS41412C-page 79
PIC18(L)F2X/4XK22
FIGURE 5-8:
DATA MEMORY MAP FOR PIC18(L)F26K22 AND PIC18(L)F46K22 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
Bank 3
Bank 4
Bank 5
Bank 6
Bank 7
Bank 8
Bank 9
Bank 10
Bank 11
Bank 12
GPR
FFh
00h
2FFh
300h
When ‘a’ = 1:
The BSR specifies the Bank
used by the instruction.
GPR
3FFh
400h
FFh
00h
GPR
4FFh
500h
FFh
00h
GPR
5FFh
600h
FFh
00h
GPR
FFh
00h
Access Bank
6FFh
700h
Access RAM Low
GPR
GPR
FFh
00h
00h
5Fh
Access RAM High 60h
(SFRs)
FFh
7FFh
800h
FFh
00h
8FFh
900h
GPR
9FFh
A00h
FFh
00h
GPR
FFh
00h
FFh
00h
FFh
00h
FFh
00h
Bank 15
AFFh
B00h
GPR
BFFh
C00h
GPR
CFFh
D00h
GPR
DFFh
E00h
GPR
GPR
SFR(1)
F00h
F37h
F38h
F5Fh
F60h
SFR
FFh
DS41412C-page 80
The second 160 bytes are
Special Function Registers
(from Bank 15).
1FFh
200h
FFh
00h
FFh
Bank 13 00h
Bank 14
The first 96 bytes are
general purpose RAM
(from Bank 0).
GPR
Bank 1
Bank 2
The BSR is ignored and the
Access Bank is used.
000h
05Fh
060h
0FFh
100h
FFFh
Preliminary
Note 1:
Addresses F38h through F5Fh are
also used by SFRs, but are not
part of the Access RAM. Users
must always use the complete
address or load the proper BSR
value to access these registers.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 5-9:
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
00h
Bank 0
100h
Bank 1
200h
300h
Bank 2
FFh
00h
From Opcode(2)
7
1
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:
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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 81
PIC18(L)F2X/4XK22
5.3.2
ACCESS BANK
5.3.3
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 96 bytes of memory (00h-5Fh) in Bank 0 and the last 160 bytes of memory (60h-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 (Figures 5-5 through 5-7).
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’,
however, the instruction is forced to use the Access
Bank address map; the current value of the BSR is
ignored entirely.
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.
5.3.4
SPECIAL FUNCTION REGISTERS
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 portion of Bank 15 (F38h to FFFh). A list of
these registers is given in Table 5-1 and Table 5-2.
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 SFRs are typically distributed among the
peripherals whose functions they control. Unused SFR
locations are unimplemented and read as ‘0’s.
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 60h and
above, this means that users can evaluate and operate
on SFRs more efficiently. The Access RAM below 60h
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 5.5.3 “Mapping the Access Bank in
Indexed Literal Offset Mode”.
DS41412C-page 82
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 5-1:
Address
SPECIAL FUNCTION REGISTER MAP FOR PIC18(L)F2X/4XK22 DEVICES
Name
Address
Name
Address
Name
Address
Name
Address
(2)
F5Fh
Name
FFFh
TOSU
FD7h
TMR0H
FAFh
SPBRG1
F87h
—
FFEh
TOSH
FD6h
TMR0L
FAEh
RCREG1
F86h
—(2)
F5Eh
CCPR3L
FFDh
TOSL
FD5h
T0CON
FADh
TXREG1
F85h
—(2)
F5Dh
CCP3CON
FFCh
STKPTR
FD4h
—(2)
FACh
TXSTA1
F84h
PORTE
F5Ch
PWM3CON
F5Bh
ECCP3AS
F5Ah
PSTR3CON
CCPR3H
FFBh
PCLATU
FD3h
OSCCON
FABh
RCSTA1
F83h
PORTD(3)
FFAh
PCLATH
FD2h
OSCCON2
FAAh
EEADRH(4)
F82h
PORTC
FF9h
PCL
FD1h
WDTCON
FA9h
EEADR
F81h
PORTB
F59h
CCPR4H
FF8h
TBLPTRU
FD0h
RCON
FA8h
EEDATA
F80h
PORTA
F58h
CCPR4L
(1)
FF7h
TBLPTRH
FCFh
TMR1H
FA7h
F7Fh
IPR5
F57h
CCP4CON
FF6h
TBLPTRL
FCEh
TMR1L
FA6h
EECON1
F7Eh
PIR5
F56h
CCPR5H
FF5h
TABLAT
FCDh
T1CON
FA5h
IPR3
F7Dh
PIE5
F55h
CCPR5L
FF4h
PRODH
FCCh
T1GCON
FA4h
PIR3
F7Ch
IPR4
F54h
CCP5CON
TMR4
EECON2
FF3h
PRODL
FCBh SSP1CON3
FA3h
PIE3
F7Bh
PIR4
F53h
FF2h
INTCON
FCAh
SSP1MSK
FA2h
IPR2
F7Ah
PIE4
F52h
PR4
FF1h
INTCON2
FC9h
SSP1BUF
FA1h
PIR2
F79h
CM1CON0
F51h
T4CON
FF0h
INTCON3
FC8h
SSP1ADD
FA0h
PIE2
F78h
CM2CON0
F50h
TMR5H
FEFh
INDF0(1)
FC7h
SSP1STAT
F9Fh
IPR1
F77h
CM2CON1
F4Fh
TMR5L
FEEh
POSTINC0(1)
FC6h SSP1CON1
F9Eh
PIR1
F76h
SPBRGH2
F4Eh
T5CON
FEDh POSTDEC0(1)
FC5h SSP1CON2
F9Dh
PIE1
F75h
SPBRG2
F4Dh
T5GCON
FECh
PREINC0(1)
FC4h
F9Ch
HLVDCON
F74h
RCREG2
F4Ch
TMR6
(1)
ADRESH
FEBh
PLUSW0
FC3h
ADRESL
F9Bh
OSCTUNE
F73h
TXREG2
F4Bh
PR6
FEAh
FSR0H
FC2h
ADCON0
F9Ah
—(2)
F72h
TXSTA2
F4Ah
T6CON
FE9h
FSR0L
FC1h
ADCON1
F99h
—(2)
F71h
RCSTA2
F49h
CCPTMRS0
FE8h
WREG
FC0h
ADCON2
F98h
—(2)
F70h
BAUDCON2
F48h
CCPTMRS1
FE7h
INDF1(1)
FBFh
CCPR1H
F97h
—(2)
F6Fh
SSP2BUF
F47h
SRCON0
FE6h
POSTINC1(1)
FBEh
CCPR1L
F96h
TRISE
F6Eh
SSP2ADD
F46h
SRCON1
FE5h POSTDEC1(1)
FBDh
CCP1CON
F95h
TRISD(3)
F6Dh
SSP2STAT
F45h
CTMUCONH
FBCh
TMR2
F94h
TRISC
F6Ch
SSP2CON1
F44h
CTMUCONL
FE4h
PREINC1(1)
FE3h
PLUSW1(1)
FBBh
PR2
F93h
TRISB
F6Bh
SSP2CON2
F43h
CTMUICON
FE2h
FSR1H
FBAh
T2CON
F92h
TRISA
F6Ah
SSP2MSK
F42h
VREFCON0
FE1h
FSR1L
FB9h PSTR1CON
F91h
—(2)
F69h
SSP2CON3
F41h
VREFCON1
FE0h
BSR
FB8h BAUDCON1
F90h
—(2)
F68h
CCPR2H
F40h
VREFCON2
(2)
PMD0
FDFh
(1)
INDF2
FB7h PWM1CON
F8Fh
—
F67h
CCPR2L
F3Fh
FDEh POSTINC2(1)
FB6h
ECCP1AS
F8Eh
—(2)
F66h
CCP2CON
F3Eh
PMD1
FDDh POSTDEC2(1)
FB5h
—(2)
F8Dh
LATE(3)
F65h
PWM2CON
F3Dh
PMD2
FB4h
T3GCON
F8Ch
LATD(3)
F64h
ECCP2AS
F3Ch
ANSELE
FDCh
PREINC2(1)
FDBh
PLUSW2
(1)
FB3h
TMR3H
F8Bh
LATC
F63h
PSTR2CON
F3Bh
ANSELD
FDAh
FSR2H
FB2h
TMR3L
F8Ah
LATB
F62h
IOCB
F3Ah
ANSELC
FD9h
FSR2L
FB1h
T3CON
F89h
LATA
F61h
WPUB
F39h
ANSELB
FD8h
STATUS
FB0h
SPBRGH1
F88h
—(2)
F60h
SLRCON
F38h
ANSELA
Note 1:
2:
3:
4:
This is not a physical register.
Unimplemented registers are read as ‘0’.
PIC18(L)F4XK22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 83
PIC18(L)F2X/4XK22
TABLE 5-2:
Address
REGISTER FILE SUMMARY FOR PIC18(L)F2X/4XK22 DEVICES
Name
Bit 7
Bit 6
Bit 5
—
—
—
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
FFFh
TOSU
FFEh
TOSH
Top-of-Stack, High Byte (TOS<15:8>)
0000 0000
FFDh
TOSL
Top-of-Stack, Low Byte (TOS<7:0>)
0000 0000
FFCh
STKPTR
STKFUL
STKUNF
—
STKPTR<4:0>
00-0 0000
FFBh
PCLATU
—
—
—
Holding Register for PC<20:16>
---0 0000
FFAh
PCLATH
Holding Register for PC<15:8>
FF9h
PCL
Holding Register for PC<7:0>
FF8h
TBLPTRU
—
Top-of-Stack, Upper Byte (TOS<20:16>)
Value on
POR, BOR
—
---0 0000
0000 0000
0000 0000
Program Memory Table Pointer Upper Byte(TBLPTR<21:16>)
--00 0000
FF7h
TBLPTRH
Program Memory Table Pointer High Byte(TBLPTR<15:8>)
0000 0000
FF6h
TBLPTRL
Program Memory Table Pointer Low Byte(TBLPTR<7:0>)
0000 0000
FF5h
TABLAT
Program Memory Table Latch
0000 0000
FF4h
PRODH
Product Register, High Byte
xxxx xxxx
FF3h
PRODL
Product Register, Low Byte
FF2h
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
FF1h
INTCON2
RBPU
INTEDG0
INTEDG1
INTEDG2
—
TMR0IP
—
RBIP
1111 -1-1
FF0h
INTCON3
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
11-0 0-00
xxxx xxxx
0000 000x
FEFh
INDF0
Uses contents of FSR0 to address data memory – value of FSR0 not changed (not a physical register)
---- ----
FEEh
POSTINC0
Uses contents of FSR0 to address data memory – value of FSR0 post-incremented (not a physical register)
---- ----
FEDh
POSTDEC0
Uses contents of FSR0 to address data memory – value of FSR0 post-decremented (not a physical register)
---- ----
FECh
PREINC0
Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register)
---- ----
FEBh
PLUSW0
Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) –
value of FSR0 offset by W
---- ----
FEAh
FSR0H
FE9h
FSR0L
FE8h
WREG
FE7h
INDF1
Uses contents of FSR1 to address data memory – value of FSR1 not changed (not a physical register)
FE6h
POSTINC1
Uses contents of FSR1 to address data memory – value of FSR1 post-incremented (not a physical register) ---- ----
FE5h
POSTDEC1
Uses contents of FSR1 to address data memory – value of FSR1 post-decremented (not a physical register) ---- ----
FE4h
PREINC1
FE3h
PLUSW1
FE2h
FSR1H
FE1h
FSR1L
FE0h
BSR
—
FDFh
INDF2
Uses contents of FSR2 to address data memory – value of FSR2 not changed (not a physical register)
FDEh
POSTINC2
Uses contents of FSR2 to address data memory – value of FSR2 post-incremented (not a physical register) ---- ----
FDDh
POSTDEC2
Uses contents of FSR2 to address data memory – value of FSR2 post-decremented (not a physical register) ---- ----
FDCh
PREINC2
FDBh
PLUSW2
—
—
—
—
Indirect Data Memory Address Pointer 0, High Byte
Indirect Data Memory Address Pointer 0, Low Byte
xxxx xxxx
Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register)
Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) –
value of FSR1 offset by W
—
—
—
Indirect Data Memory Address Pointer 1, High Byte
Indirect Data Memory Address Pointer 1, Low Byte
—
—
—
---- ----
---- ------- ------- 0000
xxxx xxxx
Bank Select Register
---- 0000
---- ----
Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) ---- ---Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) –
value of FSR2 offset by W
FDAh
FSR2H
FD9h
FSR2L
FD8h
STATUS
FD7h
TMR0H
Timer0 Register, High Byte
FD6h
TMR0L
Timer0 Register, Low Byte
FD5h
T0CON
FD3h
OSCCON
IDLEN
FD2h
OSCCON2
PLLRDY
Legend:
Note 1:
2:
3:
4:
xxxx xxxx
Working Register
—
---- 0000
—
—
—
—
Indirect Data Memory Address Pointer 2, High Byte
Indirect Data Memory Address Pointer 2, Low Byte
—
TMR0ON
—
T08BIT
—
N
T0CS
OV
T0SE
—
MFIOSEL
---- 0000
xxxx xxxx
DC
C
---x xxxx
0000 0000
xxxx xxxx
PSA
IRCF<2:0>
SOSCRUN
Z
---- ----
T0PS<2:0>
OSTS
HFIOFS
SOSCGO
PRISD
1111 1111
SCS<1:0>
MFIOFS
LFIOFS
0011 q000
00-0 01x0
x = unknown, u = unchanged, — = unimplemented, q = value depends on condition
PIC18(L)F4XK22 devices only.
PIC18(L)F2XK22 devices only.
PIC18(L)F23/24K22 and PIC18(L)F43/44K22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
DS41412C-page 84
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 5-2:
Address
REGISTER FILE SUMMARY FOR PIC18(L)F2X/4XK22 DEVICES
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
—
—
—
—
—
IPEN
SBOREN
—
RI
TO
Bit 2
FD1h
WDTCON
FD0h
RCON
FCFh
TMR1H
Timer1 Register, High Byte
FCEh
TMR1L
Timer1 Register, Low Byte
FCDh
T1CON
FCCh
T1GCON
TMR1GE
T1GPOL
T1GTM
FCBh
SSP1CON3
ACKTIM
PCIE
SCIE
FCAh
SSP1MSK
SSP1 MASK Register bits
FC9h
SSP1BUF
SSP1 Receive Buffer/Transmit Register
FC8h
SSP1ADD
FC7h
SSP1STAT
SMP
CKE
D/A
P
FC6h
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
FC5h
SSP1CON2
GCEN
ACKSTAT
ACKDT
ACKEN
FC4h
ADRESH
A/D Result, High Byte
FC3h
ADRESL
A/D Result, Low Byte
FC2h
ADCON0
—
FC1h
ADCON1
TRIGSEL
—
FC0h
ADCON2
ADFM
—
TMR1CS<1:0>
T1CKPS<1:0>
Bit 0
—
—
SWDTEN
---- ---0
PD
POR
BOR
01-1 1100
xxxx xxxx
xxxx xxxx
T1SOSCEN
T1SYNC
T1GSPM
T1GGO/
DONE
T1GVAL
BOEN
SDAHT
SBCDE
T1RD16
TMR1ON
T1GSS<1:0>
AHEN
DHEN
R/W
PEN
UA
BF
RSEN
SEN
0000 0000
0000 0000
0000 0000
xxxx xxxx
GO/DONE
—
0000 0000
xxxx xxxx
CHS<4:0>
—
0000 0000
xxxx xxxx
SSPM<3:0>
RCEN
0000 0000
0000 xx00
1111 1111
SSP1 Address Register in I2C Slave Mode. SSP1 Baud Rate Reload Register in I2C Master Mode
S
Value on
POR, BOR
Bit 1
PVCFG<1:0>
ADON
NVCFG<1:0>
ACQT<2:0>
ADCS<2:0>
--00 0000
0--- 0000
0-00 0000
FBFh
CCPR1H
Capture/Compare/PWM Register 1, High Byte
xxxx xxxx
FBEh
CCPR1L
Capture/Compare/PWM Register 1, Low Byte
xxxx xxxx
FBDh
CCP1CON
FBCh
TMR2
FBBh
PR2
FBAh
T2CON
—
FB9h
PSTR1CON
—
—
—
STR1SYNC
STR1D
STR1C
STR1B
STR1A
---0 0001
FB8h
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
0100 0-00
P1M<1:0>
DC1B<1:0>
CCP1M<3:0>
0000 0000
Timer2 Register
0000 0000
Timer2 Period Register
T2OUTPS<3:0>
1111 1111
TMR2ON
T2CKPS<1:0>
FB7h
PWM1CON
P1RSEN
FB6h
ECCP1AS
CCP1ASE
FB4h
T3GCON
TMR3GE
FB3h
TMR3H
Timer3 Register, High Byte
FB2h
TMR3L
Timer3 Register, Low Byte
FB1h
T3CON
FB0h
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
0000 0000
FAFh
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
0000 0000
FAEh
RCREG1
EUSART1 Receive Register
0000 0000
FADh
TXREG1
EUSART1 Transmit Register
FACh
TXSTA1
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
FABh
RCSTA1
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
FAAh
EEADRH(5)
—
—
—
—
—
—
FA9h
EEADR
FA8h
EEDATA
EEPROM Data Register
FA7h
EECON2
EEPROM Control Register 2 (not a physical register)
FA6h
EECON1
EEPGD
CFGS
—
FREE
WRERR
WREN
WR
RD
xx-0 x000
FA5h
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
0000 0000
FA4h
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
0000 0000
FA3h
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
0000 0000
Legend:
Note 1:
2:
3:
4:
P1DC<6:0>
-000 0000
CCP1AS<2:0>
T3GPOL
TMR3CS<1:0>
T3GTM
0000 0000
P1SSAC<1:0>
T3GSPM
T3CKPS<1:0>
T3GGO/
DONE
T3SOSCEN
P1SSBD<1:0>
0000 0000
T3GSS
0000 0x00
T3GVAL
xxxx xxxx
xxxx xxxx
T3SYNC
T3RD16
TMR3ON
0000 0000
0000 0000
EEADR<9:8>
EEADR<7:0>
0000 0010
0000 000x
---- --00
0000 0000
0000 0000
---- --00
x = unknown, u = unchanged, — = unimplemented, q = value depends on condition
PIC18(L)F4XK22 devices only.
PIC18(L)F2XK22 devices only.
PIC18(L)F23/24K22 and PIC18(L)F43/44K22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 85
PIC18(L)F2X/4XK22
TABLE 5-2:
Address
REGISTER FILE SUMMARY FOR PIC18(L)F2X/4XK22 DEVICES
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
FA2h
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
1111 1111
FA1h
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
0000 0000
FA0h
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
0000 0000
F9Fh
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
-111 1111
F9Eh
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
-000 0000
F9Dh
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
-000 0000
F9Ch
HLVDCON
VDIRMAG
BGVST
IRVST
HLVDEN
F9Bh
OSCTUNE
INTSRC
PLLEN
F96h
TRISE
WPUE3
—
F95h
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
F94h
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
F93h
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
HLVDL<3:0>
0000 0000
TUN<5:0>
—
—
—
00xx xxxx
TRISE2(1)
TRISE1(1)
TRISE0(1)
1--- -111
TRISD1
TRISD0
1111 1111
TRISC1
TRISC0
1111 1111
TRISB1
TRISB0
1111 1111
F92h
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
F8Dh
LATE(1)
—
—
—
—
—
LATE2
LATE1
LATE0
---- -xxx
F8Ch
LATD(1)
LATD7
LATD6
LATD5
LATD4
LATD3
LATD2
LATD1
LATD0
xxxx xxxx
F8Bh
LATC
LATC7
LATC6
LATC5
LATC4
LATC3
LATC2
LATC1
LATC0
xxxx xxxx
F8Ah
LATB
LATB7
LATB6
LATB5
LATB4
LATB3
LATB2
LATB1
LATB0
xxxx xxxx
F89h
LATA
LATA7
LATA6
LATA5
LATA4
LATA3
LATA2
LATA1
LATA0
xxxx xxxx
PORTE(2)
—
—
—
—
RE3
—
—
—
---- x---
PORTE(1)
—
—
—
—
RE3
RE2
RE1
RE0
---- x000
F84h
F83h
PORTD(1)
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
0000 0000
F82h
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
0000 00xx
F81h
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxx0 0000
F80h
PORTA
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
xx0x 0000
F7Fh
IPR5
—
—
—
—
—
TMR6IP
TMR5IP
TMR4IP
---- -111
F7Eh
PIR5
—
—
—
—
—
TMR6IF
TMR5IF
TMR4IF
---- -111
F7Dh
PIE5
—
—
—
—
—
TMR6IE
TMR5IE
TMR4IE
---- -000
F7Ch
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
---- -000
F7Bh
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
---- -000
F7Ah
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
---- -000
F79h
CM1CON0
C1ON
C1OUT
C1OE
C1POL
C1SP
C1R
C1CH<1:0>
0000 1000
F78h
CM2CON0
C2ON
C2OUT
C2OE
C2POL
C2SP
C2R
C2CH<1:0>
0000 1000
F77h
CM2CON1
MC1OUT
MC2OUT
C1RSEL
C2RSEL
C1HYS
C2HYS
F76h
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
0000 0000
F75h
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
0000 0000
F74h
RCREG2
EUSART2 Receive Register
0000 0000
F73h
TXREG2
EUSART2 Transmit Register
F72h
TXSTA2
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
F71h
RCSTA2
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
F70h
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
01x0 0-00
F6Fh
SSP2BUF
F6Eh
SSP2ADD
C2SYNC
xxxx xxxx
SSP2 Address Register in I2C Slave Mode. SSP2 Baud Rate Reload Register in I2C Master Mode
SSP2STAT
SMP
CKE
D/A
P
F6Ch
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
F6Bh
SSP2CON2
GCEN
ACKSTAT
ACKDT
ACKEN
F6Ah
SSP2MSK
F69h
SSP2CON3
S
R/W
0000 0000
UA
BF
PEN
RSEN
SEN
SBCDE
AHEN
DHEN
SSPM<3:0>
RCEN
PCIE
SCIE
BOEN
SDAHT
0000 0000
0000 0000
SSP1 MASK Register bits
ACKTIM
0000 0000
0000 0000
SSP2 Receive Buffer/Transmit Register
F6Dh
Legend:
Note 1:
2:
3:
4:
C1SYNC
0000 0000
1111 1111
0000 0000
x = unknown, u = unchanged, — = unimplemented, q = value depends on condition
PIC18(L)F4XK22 devices only.
PIC18(L)F2XK22 devices only.
PIC18(L)F23/24K22 and PIC18(L)F43/44K22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
DS41412C-page 86
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 5-2:
Address
REGISTER FILE SUMMARY FOR PIC18(L)F2X/4XK22 DEVICES
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
F68h
CCPR2H
Capture/Compare/PWM Register 2, High Byte
F67h
CCPR2L
Capture/Compare/PWM Register 2, Low Byte
F66h
CCP2CON
F65h
PWM2CON
P2RSEN
F64h
ECCP2AS
CCP2ASE
F63h
PSTR2CON
F62h
F61h
P2M<1:0>
DC2B<1:0>
Bit 1
Bit 0
xxxx xxxx
xxxx xxxx
CCP2M<3:0>
0000 0000
P2DC<6:0>
CCP2AS<2:0>
Value on
POR, BOR
0000 0000
P2SSAC<1:0>
P2SSBD<1:0>
0000 0000
—
—
—
STR2SYNC
STR2D
STR2C
STR2B
STR2A
---0 0001
IOCB
IOCB7
IOCB6
IOCB5
IOCB4
—
—
—
—
1111 ----
WPUB
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
1111 1111
F60h
SLRCON(2)
—
—
—
—
—
SLRC
SLRB
SLRA
---- -111
SLRCON(1)
—
—
—
SLRE
SLRD
SLRC
SLRB
SLRA
F5Fh
CCPR3H
F5Eh
CCPR3L
F5Dh
CCP3CON
F5Ch
PWM3CON
P3RSEN
F5Bh
ECCP3AS
CCP3ASE
F5Ah
PSTR3CON
F59h
CCPR4H
F58h
CCPR4L
F57h
CCP4CON
xxxx xxxx
Capture/Compare/PWM Register 3, Low Byte
xxxx xxxx
P3M<1:0>
—
DC3B<1:0>
CCP3M<3:0>
0000 0000
P3DC<6:0>
CCP3AS<2:0>
—
—
0000 0000
P3SSAC<1:0>
STR3SYNC
STR3D
STR3C
P3SSBD<1:0>
STR3B
STR3A
Capture/Compare/PWM Register 4, High Byte
—
DC4B<1:0>
0000 0000
---0 0001
xxxx xxxx
Capture/Compare/PWM Register 4, Low Byte
—
---1 1111
Capture/Compare/PWM Register 3, High Byte
xxxx xxxx
CCP4M<3:0>
--00 0000
F56h
CCPR5H
Capture/Compare/PWM Register 5, High Byte
xxxx xxxx
F55h
CCPR5L
Capture/Compare/PWM Register 5, Low Byte
xxxx xxxx
F54h
CCP5CON
F53h
TMR4
F52h
PR4
F51h
T4CON
F50h
TMR5H
Timer5 Register, High Byte
F4Fh
TMR5L
Timer5 Register, Low Byte
F4Eh
T5CON
F4Dh
T5GCON
F4Ch
TMR6
Timer6 Register
F4Bh
PR6
Timer6 Period Register
F4Ah
T6CON
F49h
CCPTMRS0
—
—
DC5B<1:0>
CCP5M<3:0>
--00 0000
Timer4 Register
0000 0000
Timer4 Period Register
—
TMR5CS<1:0>
TMR5GE
T5GPOL
—
T5CKPS<1:0>
T5GTM
TMR4ON
—
T5SYNC
T5GGO/
DONE
T5GVAL
CCPTMRS1
F47h
SRCON0
SRLEN
F46h
SRCON1
SRSPE
SRSCKE
SRSC2E
F45h
CTMUCONH
CTMUEN
—
CTMUSIDL
F44h
CTMUCONL
EDG2POL
EDG2SEL<1:0>
F43h
CTMUICON
F42h
VREFCON0
FVREN
FVRST
F41h
VREFCON1
DACEN
DACLPS
F40h
VREFCON2
—
—
—
F3Fh
PMD0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
F3Eh
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
F3Dh
PMD2
—
—
—
—
—
—
T5GSS
0000 0000
0000 0x00
TMR6ON
T6CKPS<1:0>
-000 0000
—
C1TSEL<1:0>
00-0 0-00
C4TSEL<1:0>
---- 0000
C5TSEL<1:0>
SRQEN
SRNQEN
SRPS
SRPR
SRSC1E
SRRPE
SRRCKE
SRRC2E
SRRC1E
0000 0000
TGEN
EDGEN
EDGSEQEN
IDISSEN
CTTRIG
0000 0000
EDG1POL
EDG1SEL<1:0>
FVRS<1:0>
—
0000 0000
IRNG<1:0>
0000 0000
—
—
0001 ----
—
DACNSS
000- 00-0
TMR3MD
TMR2MD
TMR1MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
00-0 0000
CTMUMD
CMP2MD
CMP1MD
ADCMD
---- 0000
—
—
0000 0000
EDG2STAT EDG1STAT
ITRIM<5:0>
DACOE
TMR5ON
1111 1111
C2TSEL<1:0>
SRCLK<2:0>
T5RD16
0000 0000
F48h
—
-000 0000
0000 0000
T5SOSCEN
T5GSPM
T4CKPS<1:0>
0000 0000
T6OUTPS<3:0>
C3TSEL<1:0>
—
1111 1111
T4OUTPS<3:0>
DACPSS<1:0>
DACR<4:0>
---0 0000
0000 0000
F3Ch
ANSELE(1)
—
—
—
—
—
ANSE2
ANSE1
ANSE0
---- -111
F3Bh
ANSELD(1)
ANSD7
ANSD6
ANSD5
ANSD4
ANSD3
ANSD2
ANSD1
ANSD0
1111 1111
Legend:
Note 1:
2:
3:
4:
x = unknown, u = unchanged, — = unimplemented, q = value depends on condition
PIC18(L)F4XK22 devices only.
PIC18(L)F2XK22 devices only.
PIC18(L)F23/24K22 and PIC18(L)F43/44K22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 87
PIC18(L)F2X/4XK22
TABLE 5-2:
Address
Name
REGISTER FILE SUMMARY FOR PIC18(L)F2X/4XK22 DEVICES
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
F3Ah
ANSELC
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
1111 11--
F39h
ANSELB
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
ANSB0
--11 1111
F38h
ANSELA
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
--1- 1111
Legend:
Note 1:
2:
3:
4:
x = unknown, u = unchanged, — = unimplemented, q = value depends on condition
PIC18(L)F4XK22 devices only.
PIC18(L)F2XK22 devices only.
PIC18(L)F23/24K22 and PIC18(L)F43/44K22 devices only.
PIC18(L)F26K22 and PIC18(L)F46K22 devices only.
DS41412C-page 88
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
5.3.5
STATUS REGISTER
The STATUS register, shown in Register 5-2, 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 5-2:
U-0
For other instructions that do not affect Status bits, see
the instruction set summaries in Table 25.2 and
Table 25-3.
Note:
The C and DC bits operate as the borrow
and digit borrow bits, respectively, in
subtraction.
STATUS: 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
OV
R/W-x
R/W-x
R/W-x
(1)
Z
C(1)
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 (two’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 (two’s complement). It indicates an overflow of the 7-bit magnitude which causes the sign bit (bit 7 of the result) 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 (ADDWF, ADDLW,SUBLW,SUBWF instructions)(1)
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 (ADDWF, ADDLW, SUBLW, SUBWF instructions)(1)
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:
For Borrow, the polarity is reversed. A subtraction is executed by adding the two’s complement of the
second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high-order or low-order
bit of the source register.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 89
PIC18(L)F2X/4XK22
5.4
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 5.5 “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
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.
5.4.3
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 5.5.1 “Indexed
Addressing with Literal Offset”.
5.4.1
The Access RAM bit ‘a’ determines how the address is
interpreted. When ‘a’ is ‘1’, the contents of the BSR
(Section 5.3.1 “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.
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.
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 which are to be read
or written. Since the FSRs are themselves located in
RAM as Special File 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 5-5.
EXAMPLE 5-5:
NEXT
5.4.2
INDIRECT ADDRESSING
LFSR
CLRF
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.
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 5.3.3 “General
Purpose Register File”) or a location in the Access
Bank (Section 5.3.2 “Access Bank”) as the data
source for the instruction.
DS41412C-page 90
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
5.4.3.1
FSR Registers and the INDF
Operand
5.4.3.2
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. Each FSR pair
holds a 12-bit value, therefore, the four upper bits of the
FSRnH register are not used. The 12-bit FSR value 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 which cannot be directly
read or written. Accessing these registers actually
accesses the location to which the associated FSR
register pair points, and also performs a specific action
on the FSR value. They are:
• POSTDEC: accesses the location to which the
FSR points, then automatically decrements the
FSR by 1 afterwards
• POSTINC: accesses the location to which the
FSR points, then automatically increments the
FSR by 1 afterwards
• PREINC: automatically increments the FSR by 1,
then uses the location to which the FSR points 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 location to which the result points 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.
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 5-10:
FSR Registers and POSTINC,
POSTDEC, PREINC and PLUSW
In this context, accessing an INDF register uses the
value in the associated FSR register without changing
it. Similarly, accessing a PLUSW register gives the
FSR value an offset by that in the W register; however,
neither W nor the FSR is actually changed in the
operation. Accessing the other virtual registers
changes the value of the FSR register.
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.
E00h
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.
Bank 14
F00h
FFFh
Bank 15
Data Memory
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 91
PIC18(L)F2X/4XK22
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.).
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.
5.4.3.3
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 either
the INDF2 or POSTDEC2 register 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.
5.5
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.
5.5.1
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.
5.5.2
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 is shown in
Figure 5-11.
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 25.2.1
“Extended Instruction Syntax”.
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 remain unchanged.
DS41412C-page 92
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 5-11:
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 F60h to FFFh
(Bank 15) of data memory.
Locations below 60h are not
available in this addressing
mode.
000h
060h
Bank 0
100h
00h
Bank 1
through
Bank 14
60h
Valid range
for ‘f’
Access RAM
F00h
FFh
Bank 15
F60h
SFRs
FFFh
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’.
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.
Data Memory
000h
060h
Bank 0
100h
001001da ffffffff
Bank 1
through
Bank 14
FSR2H
FSR2L
F00h
Bank 15
F60h
SFRs
FFFh
Data Memory
BSR
00000000
000h
060h
Bank 0
100h
Bank 1
through
Bank 14
001001da ffffffff
F00h
Bank 15
F60h
SFRs
FFFh
 2010 Microchip Technology Inc.
Data Memory
Preliminary
DS41412C-page 93
PIC18(L)F2X/4XK22
5.5.3
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 section of Bank 0, this
mode maps the contents from 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 5.3.2 “Access
Bank”). An example of Access Bank remapping in this
addressing mode is shown in Figure 5-12.
FIGURE 5-12:
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.
5.6
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 25.2 “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
Bank 0
100h
120h
17Fh
200h
Bank 1
Window
00h
Bank 1
Bank 1 “Window”
5Fh
60h
Special File Registers at
F60h through FFFh are
mapped to 60h through
FFh, as usual.
Bank 2
through
Bank 14
Bank 0 addresses below
5Fh can still be addressed
by using the BSR.
SFRs
FFh
Access Bank
F00h
Bank 15
F60h
FFFh
SFRs
Data Memory
DS41412C-page 94
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
6.0
FLASH PROGRAM MEMORY
6.1
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 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 64 bytes at a time. The difference
between the write and erase block sizes requires from
1 to 8 block writes to restore the contents of a single
block erase. A bulk erase operation can 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.
FIGURE 6-1:
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).
The table read operation retrieves one byte of data
directly from program memory and places it into the
TABLAT register. Figure 6-1 shows the operation of a
table read.
The table write operation stores one byte of data from the
TABLAT register into a write block holding register. The
procedure to write the contents of the holding registers
into program memory is detailed in Section 6.5 “Writing
to Flash Program Memory”. Figure 6-2 shows the
operation of a table write with program memory and data
RAM.
Table operations work with byte entities. Tables
containing data, rather than program instructions, are
not required to be word aligned. Therefore, a table 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.
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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 95
PIC18(L)F2X/4XK22
FIGURE 6-2:
TABLE WRITE OPERATION
Instruction: TBLWT*
Program Memory
Table Pointer(1)
TBLPTRU
TBLPTRH
Holding Registers
Table Latch (8-bit)
TBLPTRL
TABLAT
Program Memory
(TBLPTR<MSBs>)
Note 1: During table writes the Table Pointer does not point directly to Program Memory. The LSBs of TBLPRTL
actually point to an address within the write block holding registers. The MSBs of the Table Pointer determine where the write block will eventually be written. The process for writing the holding registers to the
program memory array is discussed in Section 6.5 “Writing to Flash Program Memory”.
6.2
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
6.2.1
The FREE bit allows the program memory erase
operation. When FREE is set, an erase operation is
initiated on the next WR command. When FREE is
clear, only writes are enabled.
The WREN bit, when set, will allow a write operation.
The WREN bit is clear on power-up.
EECON1 AND EECON2 REGISTERS
The EECON1 register (Register 6-1) 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 EEPGD control bit determines if the access will be
a program or data EEPROM memory access. When
EEPGD is clear, any subsequent operations will
operate on the data EEPROM memory. When EEPGD
is set, any subsequent operations will operate on the
program memory.
The WRERR bit is set by hardware when the WR bit is
set and cleared when the internal programming timer
expires and the write operation is complete.
Note:
The WR control bit initiates write operations. The WR
bit cannot be cleared, only set, by firmware. Then WR
bit is cleared by hardware at the completion of the write
operation.
Note:
The CFGS control bit determines if the access will be
to the Configuration/Calibration registers or to program
memory/data EEPROM memory. When CFGS is set,
subsequent operations will operate on Configuration
registers regardless of EEPGD (see Section 24.0
“Special Features of the CPU”). When CFGS is clear,
memory selection access is determined by EEPGD.
DS41412C-page 96
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.
Preliminary
The EEIF interrupt flag bit of the PIR2
register is set when the write is complete.
The EEIF flag stays set until cleared by
firmware.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 6-1:
EECON1: DATA EEPROM CONTROL 1 REGISTER
R/W-x
R/W-x
U-0
R/W-0
R/W-x
R/W-0
R/S-0
R/S-0
EEPGD
CFGS
—
FREE
WRERR
WREN
WR
RD
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
S = Bit can be set by software, but not cleared
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘0’ = Bit is cleared
‘1’ = Bit is set
x = Bit is unknown
bit 7
EEPGD: Flash Program or Data EEPROM Memory Select bit
1 = Access Flash program memory
0 = Access data EEPROM memory
bit 6
CFGS: Flash Program/Data EEPROM or Configuration Select bit
1 = Access Configuration registers
0 = Access Flash program or data EEPROM memory
bit 5
Unimplemented: Read as ‘0’
bit 4
FREE: Flash Row (Block) Erase Enable bit
1 = Erase the program memory block addressed by TBLPTR on the next WR command
(cleared by completion of erase operation)
0 = Perform write-only
bit 3
WRERR: Flash Program/Data EEPROM Error Flag bit(1)
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/Data EEPROM Write Enable bit
1 = Allows write cycles to Flash program/data EEPROM
0 = Inhibits write cycles to Flash program/data EEPROM
bit 1
WR: Write Control bit
1 = Initiates a data EEPROM erase/write cycle or 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) by software.)
0 = Write cycle to the EEPROM is complete
bit 0
RD: Read Control bit
1 = Initiates an EEPROM read (Read takes one cycle. RD is cleared by hardware. The RD bit can only
be set (not cleared) by software. RD bit cannot be set when EEPGD = 1 or CFGS = 1.)
0 = Does not initiate an EEPROM read
Note 1:
When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the
error condition.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 97
PIC18(L)F2X/4XK22
6.2.2
TABLAT – TABLE LATCH REGISTER
When a TBLRD is executed, all 22 bits of the TBLPTR
determine which byte is read from program memory
directly into the TABLAT register.
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.
6.2.3
When a TBLWT is executed the byte in the TABLAT
register is written, not to Flash memory but, to a holding
register in preparation for a program memory write. The
holding registers constitute a write block which varies
depending on the device (see Table 6-1).The 3, 4, or 5
LSbs of the TBLPTRL register determine which specific
address within the holding register block is written to.
The MSBs of the Table Pointer have no effect during
TBLWT operations.
TBLPTR – TABLE POINTER
REGISTER
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 a program memory write is executed the entire
holding register block is written to the Flash memory at
the address determined by the MSbs of the TBLPTR.
The 3, 4, or 5 LSBs are ignored during Flash memory
writes. For more detail, see Section 6.5 “Writing to
Flash Program Memory”.
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 on the TBLPTR
affect only the low-order 21 bits.
6.2.4
When an erase of program memory is executed, the
16 MSbs of the Table Pointer register (TBLPTR<21:6>)
point to the 64-byte block that will be erased. The Least
Significant bits (TBLPTR<5:0>) are ignored.
Figure 6-3 describes the relevant boundaries of
TBLPTR based on Flash program memory operations.
TABLE POINTER BOUNDARIES
TBLPTR is used in reads, writes and erases of the
Flash program memory.
TABLE 6-1:
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 6-3:
21
TABLE POINTER BOUNDARIES BASED ON OPERATION
TBLPTRU
16
TBLPTRH
15
8
TABLE ERASE/WRITE
TBLPTR<21:n+1>(1)
7
TBLPTRL
0
TABLE WRITE
TBLPTR<n:0>(1)
TABLE READ – TBLPTR<21:0>
Note 1: n = 6 for block sizes of 64 bytes.
DS41412C-page 98
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
6.3
Reading the Flash Program
Memory
The TBLRD instruction retrieves data from program
memory and places it into data RAM. Table reads from
program memory are performed one byte at a time.
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 6-4
shows the interface between the internal program
memory and the TABLAT.
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.
FIGURE 6-4:
READS FROM FLASH PROGRAM MEMORY
Program Memory
(Even Byte Address)
(Odd Byte Address)
TBLPTR = xxxxx1
Instruction Register
(IR)
EXAMPLE 6-1:
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*+
MOVFW
MOVF
TABLAT, W
WORD_EVEN
TABLAT, W
WORD_ODD
 2010 Microchip Technology Inc.
; read into TABLAT and increment
; get data
; read into TABLAT and increment
; get data
Preliminary
DS41412C-page 99
PIC18(L)F2X/4XK22
6.4
Erasing Flash Program Memory
The minimum erase block is 32 words or 64 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 64 bytes of program
memory is erased. The Most Significant 16 bits of the
TBLPTR<21:6> point to the block being erased. The
TBLPTR<5:0> bits are ignored.
The EECON1 register commands the erase operation.
The EEPGD bit must be set to point to the Flash
program memory. The WREN bit must be set to enable
write operations. The FREE bit is set to select an erase
operation.
The write initiate sequence for EECON2, shown as
steps 4 through 6 in Section 6.4.1 “Flash Program
Memory Erase Sequence”, is used to guard against
accidental writes. This is sometimes referred to as a
long write.
6.4.1
FLASH PROGRAM MEMORY
ERASE SEQUENCE
The sequence of events for erasing a block of internal
program memory is:
1.
Load Table Pointer register with address of
block being erased.
Set the EECON1 register for the erase operation:
• set EEPGD bit to point to program memory;
• clear the CFGS bit to access program memory;
• set WREN bit to enable writes;
• set FREE bit to enable the erase.
Disable interrupts.
Write 55h to EECON2.
Write 0AAh to EECON2.
Set the WR bit. This will begin the block erase
cycle.
The CPU will stall for duration of the erase
(about 2 ms using internal timer).
Re-enable interrupts.
2.
3.
4.
5.
6.
7.
8.
A long write is necessary for erasing the internal Flash.
Instruction execution is halted during the long write
cycle. The long write is terminated by the internal
programming timer.
EXAMPLE 6-2:
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
BCF
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
EECON1,
EECON1,
EECON1,
EECON1,
INTCON,
55h
EECON2
0AAh
EECON2
EECON1,
INTCON,
;
;
;
;
;
ERASE_BLOCK
Required
Sequence
DS41412C-page 100
EEPGD
CFGS
WREN
FREE
GIE
point to Flash program memory
access Flash program memory
enable write to memory
enable block Erase operation
disable interrupts
; write 55h
WR
GIE
; write 0AAh
; start erase (CPU stall)
; re-enable interrupts
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
6.5
Writing to Flash Program Memory
The programming block size is 64 bytes. Word or byte
programming is not supported.
The long write is necessary for programming the
internal Flash. Instruction execution is halted during a
long write cycle. The long write will be terminated by
the internal programming timer.
Table writes are used internally to load the holding
registers needed to program the Flash memory. There
are only as many holding registers as there are bytes
in a write block (64 bytes).
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.
Since the Table Latch (TABLAT) is only a single byte,
the TBLWT instruction needs 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. After all the holding
registers have been written, the programming
operation of that block of memory is started by
configuring the EECON1 register for a program
memory write and performing the long write sequence.
FIGURE 6-5:
Note:
The default value of the holding registers on
device Resets and after write operations is
FFh. A write of FFh to a holding register
does not modify that byte. This means that
individual bytes of program memory may be
modified, provided that the change does not
attempt to change any bit from a ‘0’ to a ‘1’.
When modifying individual bytes, it is not
necessary to load all holding registers
before executing a long write operation.
TABLE WRITES TO FLASH PROGRAM MEMORY
TABLAT
Write Register
8
8
TBLPTR = xxxx00
TBLPTR = xxxx01
Holding Register
8
TBLPTR = xxxxYY(1)
TBLPTR = xxxx02
Holding Register
8
Holding Register
Holding Register
Program Memory
Note 1: YY = 3F for 64 byte write blocks.
6.5.1
FLASH PROGRAM MEMORY WRITE
SEQUENCE
The sequence of events for programming an internal
program memory location should be:
1.
2.
3.
4.
5.
6.
7.
Read 64 bytes into RAM.
Update data values in RAM as necessary.
Load Table Pointer register with address being
erased.
Execute the block erase procedure.
Load Table Pointer register with address of first
byte being written.
Write the 64-byte block into the holding registers
with auto-increment.
Set the EECON1 register for the write operation:
• set EEPGD bit to point to program memory;
• clear the CFGS bit to access program memory;
• set WREN to enable byte writes.
 2010 Microchip Technology Inc.
8.
9.
10.
11.
12.
Disable interrupts.
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).
13. Re-enable interrupts.
14. Verify the memory (table read).
This procedure will require about 6 ms to update each
write block of memory. An example of the required code
is given in Example 6-3.
Note:
Preliminary
Before setting the WR bit, the Table
Pointer address needs to be within the
intended address range of the bytes in the
holding registers.
DS41412C-page 101
PIC18(L)F2X/4XK22
EXAMPLE 6-3:
WRITING TO FLASH PROGRAM MEMORY
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
D'64’
COUNTER
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
; number of bytes in erase block
TBLRD*+
MOVF
MOVWF
DECFSZ
BRA
TABLAT, W
POSTINC0
COUNTER
READ_BLOCK
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
NEW_DATA_LOW
POSTINC0
NEW_DATA_HIGH
INDF0
; point to buffer
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BCF
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
TBLRD*MOVLW
MOVWF
MOVLW
MOVWF
CODE_ADDR_UPPER
TBLPTRU
CODE_ADDR_HIGH
TBLPTRH
CODE_ADDR_LOW
TBLPTRL
EECON1, EEPGD
EECON1, CFGS
EECON1, WREN
EECON1, FREE
INTCON, GIE
55h
EECON2
0AAh
EECON2
EECON1, WR
INTCON, GIE
; load TBLPTR with the base
; address of the memory block
MOVLW
MOVWF
MOVLW
MOVWF
BlockSize
COUNTER
D’64’/BlockSize
COUNTER2
MOVF
MOVWF
TBLWT+*
POSTINC0, W
TABLAT
; point to buffer
; Load TBLPTR with the base
; address of the memory block
READ_BLOCK
;
;
;
;
;
read into TABLAT, and inc
get data
store data
done?
repeat
MODIFY_WORD
; update buffer word
ERASE_BLOCK
Required
Sequence
BUFFER_ADDR_HIGH
FSR0H
BUFFER_ADDR_LOW
FSR0L
;
;
;
;
;
point to Flash program memory
access Flash program memory
enable write to memory
enable Erase operation
disable interrupts
; write 55h
;
;
;
;
;
write 0AAh
start erase (CPU stall)
re-enable interrupts
dummy read decrement
point to buffer
WRITE_BUFFER_BACK
; number of bytes in holding register
; number of write blocks in 64 bytes
WRITE_BYTE_TO_HREGS
DS41412C-page 102
Preliminary
;
;
;
;
get low byte of buffer data
present data to table latch
write data, perform a short write
to internal TBLWT holding register.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
EXAMPLE 6-3:
WRITING TO FLASH PROGRAM MEMORY (CONTINUED)
DECFSZ
BRA
COUNTER
WRITE_WORD_TO_HREGS
; loop until holding registers are full
BSF
BCF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
DCFSZ
BRA
BSF
BCF
EECON1, EEPGD
EECON1, CFGS
EECON1, WREN
INTCON, GIE
55h
EECON2
0AAh
EECON2
EECON1, WR
COUNTER2
WRITE_BYTE_TO_HREGS
INTCON, GIE
EECON1, WREN
;
;
;
;
PROGRAM_MEMORY
Required
Sequence
6.5.2
WRITE VERIFY
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 WRERR bit will be set
which the user can check to decide whether a rewrite
of the location(s) is needed.
TABLE 6-2:
Name
TBLPTRU
; write 55h
;
;
;
;
;
;
write 0AAh
start program (CPU stall)
repeat for remaining write blocks
re-enable interrupts
disable write to memory
6.5.4
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.
6.5.3
point to Flash program memory
access Flash program memory
enable write to memory
disable interrupts
PROTECTION AGAINST
SPURIOUS WRITES
To protect against spurious writes to Flash program
memory, the write initiate sequence must also be
followed. See Section 24.0 “Special Features of the
CPU” for more detail.
6.6
Flash Program Operation During
Code Protection
See Section 24.3 “Program Verification and Code
Protection” for details on code protection of Flash
program memory.
REGISTERS ASSOCIATED WITH PROGRAM FLASH MEMORY
Bit 7
—
Bit 6
—
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Program Memory Table Pointer Upper Byte (TBLPTR<21:16>)
Reset
Values on
page
—
TBPLTRH
Program Memory Table Pointer High Byte (TBLPTR<15:8>)
—
TBLPTRL
Program Memory Table Pointer Low Byte (TBLPTR<7:0>)
—
TABLAT
INTCON
Program Memory Table Latch
GIE/GIEH
PEIE/GIEL
EECON1
EEPGD
CFGS
—
FREE
WRERR
IPR2
OSCFIP
C1IP
C2IP
EEIP
PIR2
OSCFIF
C1IF
C2IF
EEIF
PIE2
OSCFIE
C1IE
C2IE
EEIE
EECON2
Legend:
TMR0IE
INT0IE
RBIE
—
TMR0IF
INT0IF
RBIF
115
WREN
WR
RD
97
BCLIP
HLVDIP
TMR3IP
CCP2IP
128
BCLIF
HLVDIF
TMR3IF
CCP2IF
119
BCLIE
HLVDIE
TMR3IE
CCP2IE
124
EEPROM Control Register 2 (not a physical register)
—
— = unimplemented, read as ‘0’. Shaded bits are not used during Flash/EEPROM access.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 103
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 104
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
7.0
DATA EEPROM MEMORY
The data EEPROM is a nonvolatile memory array,
separate from the data RAM and program memory,
which is used for long-term storage of program data. It
is not directly mapped in either the register file or
program memory space but is indirectly addressed
through the Special Function Registers (SFRs). The
EEPROM is readable and writable during normal
operation over the entire VDD range.
Four SFRs are used to read and write to the data
EEPROM as well as the program memory. They are:
•
•
•
•
•
EECON1
EECON2
EEDATA
EEADR
EEADRH
The EEPROM data memory is rated for high erase/write
cycle endurance. A byte write automatically erases the
location and writes the new data (erase-before-write).
The write time is controlled by an on-chip timer; it will
vary with voltage and temperature as well as from chipto-chip. Please refer to the Data EEPROM Memory
parameters in Section 27.0 “Electrical Characteristics” for limits.
EEADR and EEADRH Registers
The EEADR register is used to address the data
EEPROM for read and write operations. The 8-bit
range of the register can address a memory range of
256 bytes (00h to FFh). The EEADRH register expands
the range to 1024 bytes by adding an additional two
address bits.
7.2
EECON1 and EECON2 Registers
Access to the data EEPROM is controlled by two
registers: EECON1 and EECON2. These are the same
registers which control access to the program memory
and are used in a similar manner for the data
EEPROM.
 2010 Microchip Technology Inc.
Control bit, CFGS, determines if the access will be to
the Configuration registers or to program memory/data
EEPROM memory. When the CFGS bit is set,
subsequent operations access Configuration registers.
When the CFGS bit is clear, the EEPGD bit selects
either program Flash or data EEPROM memory.
The WREN bit, when set, will allow a write operation.
On power-up, the WREN bit is clear.
The data EEPROM allows byte read and write. When
interfacing to the data memory block, EEDATA holds
the 8-bit data for read/write and the EEADR:EEADRH
register pair hold the address of the EEPROM location
being accessed.
7.1
The EECON1 register (Register 7-1) is the control
register for data and program memory access. Control
bit EEPGD determines if the access will be to program
or data EEPROM memory. When the EEPGD bit is
clear, operations will access the data EEPROM
memory. When the EEPGD bit is set, program memory
is accessed.
The WRERR bit is set by 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
may 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
can be set but not cleared by software. It is cleared only
by hardware at the completion of the write operation.
Note:
The EEIF interrupt flag bit of the PIR2
register is set when the write is complete.
It must be cleared by software.
Control bits, RD and WR, start read and erase/write
operations, respectively. These bits are set by firmware
and cleared by hardware at the completion of the
operation.
The RD bit cannot be set when accessing program
memory (EEPGD = 1). Program memory is read using
table read instructions. See Section 6.1 “Table Reads
and Table Writes” regarding table reads.
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.
Preliminary
DS41412C-page 105
PIC18(L)F2X/4XK22
REGISTER 7-1:
EECON1: DATA EEPROM CONTROL 1 REGISTER
R/W-x
R/W-x
U-0
R/W-0
R/W-x
R/W-0
R/S-0
R/S-0
EEPGD
CFGS
—
FREE
WRERR
WREN
WR
RD
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
S = Bit can be set by software, but not cleared
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘0’ = Bit is cleared
‘1’ = Bit is set
x = Bit is unknown
bit 7
EEPGD: Flash Program or Data EEPROM Memory Select bit
1 = Access Flash program memory
0 = Access data EEPROM memory
bit 6
CFGS: Flash Program/Data EEPROM or Configuration Select bit
1 = Access Configuration registers
0 = Access Flash program or data EEPROM memory
bit 5
Unimplemented: Read as ‘0’
bit 4
FREE: Flash Row (Block) Erase Enable bit
1 = Erase the program memory block addressed by TBLPTR on the next WR command
(cleared by completion of erase operation)
0 = Perform write-only
bit 3
WRERR: Flash Program/Data EEPROM Error Flag bit(1)
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/Data EEPROM Write Enable bit
1 = Allows write cycles to Flash program/data EEPROM
0 = Inhibits write cycles to Flash program/data EEPROM
bit 1
WR: Write Control bit
1 = Initiates a data EEPROM erase/write cycle or 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) by software.)
0 = Write cycle to the EEPROM is complete
bit 0
RD: Read Control bit
1 = Initiates an EEPROM read (Read takes one cycle. RD is cleared by hardware. The RD bit can only
be set (not cleared) by software. RD bit cannot be set when EEPGD = 1 or CFGS = 1.)
0 = Does not initiate an EEPROM read
Note 1:
When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the
error condition.
DS41412C-page 106
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
7.3
Reading the Data EEPROM
Memory
To read a data memory location, the user must write the
address to the EEADR register, clear the EEPGD control bit of the EECON1 register and then set control bit,
RD. The data is available on the very next instruction
cycle; therefore, the EEDATA register can be read by
the next instruction. EEDATA will hold this value until
another read operation, or until it is written to by the
user (during a write operation).
The basic process is shown in Example 7-1.
7.4
Writing to the Data EEPROM
Memory
Additionally, the WREN bit in EECON1 must be set to
enable writes. This mechanism prevents accidental
writes to data EEPROM due to unexpected code
execution (i.e., runaway programs). The WREN bit
should be kept clear at all times, except when updating
the EEPROM. The WREN bit is not cleared by
hardware.
After a write sequence has been initiated, EECON1,
EEADR and EEDATA cannot be modified. The WR bit
will be inhibited from being set unless the WREN bit is
set. Both WR and WREN cannot be set with the same
instruction.
At the completion of the write cycle, the WR bit is
cleared by hardware and the EEPROM Interrupt Flag
bit, EEIF, is set. The user may either enable this
interrupt or poll this bit. EEIF must be cleared by
software.
To write an EEPROM data location, the address must
first be written to the EEADR register and the data written to the EEDATA register. The sequence in
Example 7-2 must be followed to initiate the write cycle.
7.5
The write will not begin if this sequence is not exactly
followed (write 55h to EECON2, write 0AAh to
EECON2, then set WR bit) for each byte. It is strongly
recommended that interrupts be disabled during this
code segment.
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.
EXAMPLE 7-1:
MOVLW
MOVWF
BCF
BCF
BSF
MOVF
DATA EEPROM READ
DATA_EE_ADDR
EEADR
EECON1, EEPGD
EECON1, CFGS
EECON1, RD
EEDATA, W
EXAMPLE 7-2:
Required
Sequence
Write Verify
;
;
;
;
;
;
Data Memory Address to read
Point to DATA memory
Access EEPROM
EEPROM Read
W = EEDATA
DATA EEPROM WRITE
MOVLW
MOVWF
MOVLW
MOVWF
MOVLW
MOVWF
BCF
BCF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
DATA_EE_ADDR_LOW
EEADR
DATA_EE_ADDR_HI
EEADRH
DATA_EE_DATA
EEDATA
EECON1, EEPGD
EECON1, CFGS
EECON1, WREN
INTCON, GIE
55h
EECON2
0AAh
EECON2
EECON1, WR
INTCON, GIE
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
BCF
EECON1, WREN
; User code execution
; Disable writes on write complete (EEIF set)
 2010 Microchip Technology Inc.
Data Memory Address to write
Data Memory Value to write
Point to DATA memory
Access EEPROM
Enable writes
Disable Interrupts
Write 55h
Write 0AAh
Set WR bit to begin write
Enable Interrupts
Preliminary
DS41412C-page 107
PIC18(L)F2X/4XK22
7.6
Operation During Code-Protect
Data EEPROM memory has its own code-protect bits in
Configuration Words. External read and write
operations are disabled if code protection is enabled.
The microcontroller itself can both read and write to the
internal data EEPROM, regardless of the state of the
code-protect Configuration bit. Refer to Section 24.0
“Special Features of the CPU” for additional
information.
7.7
Protection Against Spurious Write
There are conditions when the user may not want to
write to the data EEPROM memory. To protect against
spurious EEPROM writes, various mechanisms have
been implemented. On power-up, the WREN bit is
cleared. In addition, writes to the EEPROM are blocked
during the Power-up Timer period (TPWRT).
The write initiate sequence and the WREN bit together
help prevent an accidental write during brown-out,
power glitch or software malfunction.
7.8
Using the Data EEPROM
The data EEPROM is a high-endurance, byte
addressable array that has been optimized for the
storage of frequently changing information (e.g.,
program variables or other data that are updated often).
When variables in one section change frequently, while
variables in another section do not change, it is possible
to exceed the total number of write cycles to the
EEPROM without exceeding the total number of write
cycles to a single byte. Refer to the Data EEPROM
Memory parameters in Section 27.0 “Electrical
Characteristics” for write cycle limits. If this is the case,
then an array refresh must be performed. For this
reason, variables that change infrequently (such as
constants, IDs, calibration, etc.) should be stored in
Flash program memory.
A simple data EEPROM refresh routine is shown in
Example 7-3.
Note:
EXAMPLE 7-3:
DATA EEPROM REFRESH ROUTINE
CLRF
BCF
BCF
BCF
BSF
EEADR
EECON1,
EECON1,
INTCON,
EECON1,
BSF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BTFSC
BRA
INCFSZ
BRA
EECON1, RD
55h
EECON2
0AAh
EECON2
EECON1, WR
EECON1, WR
$-2
EEADR, F
LOOP
BCF
BSF
EECON1, WREN
INTCON, GIE
CFGS
EEPGD
GIE
WREN
Loop
DS41412C-page 108
If data EEPROM is only used to store
constants and/or data that changes rarely,
an array refresh is likely not required. See
specification.
;
;
;
;
;
;
;
;
;
;
;
;
;
Start at address 0
Set for memory
Set for Data EEPROM
Disable interrupts
Enable writes
Loop to refresh array
Read current address
Write 55h
Write 0AAh
Set WR bit to begin write
Wait for write to complete
; Increment address
; Not zero, do it again
; Disable writes
; Enable interrupts
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 7-1:
Name
REGISTERS ASSOCIATED WITH DATA EEPROM MEMORY
Bit 7
Bit 6
INTCON
GIE/GIEH
PEIE/GIEL
EEADR
EEADR7
EEADR6
—
—
(1)
EEADRH
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
EEADR5 EEADR4 EEADR3 EEADR2 EEADR1 EEADR0
—
—
—
EEDATA
EEPROM Data Register
EECON2
EEPROM Control Register 2 (not a physical register)
—
EEADR9 EEADR8
—
—
—
—
EECON1
EEPGD
CFGS
—
FREE
WRERR
WREN
WR
RD
106
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
Legend: — = unimplemented, read as ‘0’. Shaded bits are not used during EEPROM access.
Note 1: PIC18(L)F26K22 and PIC18(L)F46K22 only.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 109
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 110
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
8.0
8 x 8 HARDWARE MULTIPLIER
8.1
Introduction
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.
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 .
8.2
EXAMPLE 8-1:
MOVF
MULWF
ARG1, W
ARG2
EXAMPLE 8-2:
MOVF
MULWF
ARG1, W
ARG2
BTFSC
SUBWF
ARG2, SB
PRODH, F
MOVF
BTFSC
SUBWF
ARG2, W
ARG1, SB
PRODH, F
8 x 8 UNSIGNED
MULTIPLY ROUTINE
;
; ARG1 * ARG2 ->
; PRODH:PRODL
8 x 8 SIGNED MULTIPLY
ROUTINE
;
;
;
;
;
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:
Routine
8 x 8 unsigned
8 x 8 signed
16 x 16 unsigned
16 x 16 signed
PERFORMANCE COMPARISON FOR VARIOUS MULTIPLY OPERATIONS
Multiply Method
Program
Memory
(Words)
Without hardware multiply
13
Time
Cycles
(Max) @ 64 MHz @ 40 MHz @ 10 MHz @ 4 MHz
69
4.3 s
6.9 s
27.6 s
69 s
Hardware multiply
1
1
62.5 ns
100 ns
400 ns
1 s
Without hardware multiply
33
91
5.7 s
9.1 s
36.4 s
91 s
Hardware multiply
6
6
375 ns
600 ns
2.4 s
6 s
Without hardware multiply
21
242
15.1 s
24.2 s
96.8 s
242 s
Hardware multiply
28
28
1.8 s
2.8 s
11.2 s
28 s
Without hardware multiply
52
254
15.9 s
25.4 s
102.6 s
254 s
Hardware multiply
35
40
2.5 s
4.0 s
16.0 s
40 s
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 111
PIC18(L)F2X/4XK22
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 (RES<3:0>).
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
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
;
;
;
;
;
;
;
;
;
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
(RES<3:0>). To account for the sign bits of the arguments, the MSb for each argument pair is tested and
the appropriate subtractions are done.
DS41412C-page 112
ARG1L, W
ARG2L
;
;
;
;
;
;
;
;
;
;
;
MOVF
MULWF
;
;
;
;
;
;
;
;
;
;
16 x 16 SIGNED
MULTIPLY ROUTINE
;
;
; ARG1H * ARG2H->
; PRODH:PRODL
;
;
16 x 16 SIGNED
MULTIPLICATION
ALGORITHM
;
SIGN_ARG1
BTFSS
BRA
MOVF
SUBWF
MOVF
SUBWFB
;
CONT_CODE
:
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
9.0
INTERRUPTS
9.2
The PIC18(L)F2X/4XK22 devices have multiple
interrupt sources and an interrupt priority feature that
allows most interrupt sources to be assigned a high or
low priority level (INT0 does not have a priority bit, it is
always a high priority). The high priority interrupt vector
is at 0008h and the low priority interrupt vector is at
0018h. A high priority interrupt event will interrupt a low
priority interrupt that may be in progress.
There are 19 registers used to control interrupt
operation.
These registers are:
•
•
•
•
•
INTCON, INTCON2, INTCON3
PIR1, PIR2, PIR3, PIR4, PIR5
PIE1, PIE2, PIE3, PIE4, PIE5
IPR1, IPR2, IPR3, IPR4, IPR5
RCON
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
9.1
Mid-Range Compatibility
When the IPEN bit is cleared (default state), the interrupt
priority feature is disabled and interrupts are compatible
with PIC® microcontroller mid-range devices. In
Compatibility mode, the interrupt priority bits of the IPRx
registers have no effect. The PEIE/GIEL bit of the
INTCON register is the global interrupt enable for the
peripherals. The PEIE/GIEL bit disables only the
peripheral interrupt sources and enables the peripheral
interrupt sources when the GIE/GIEH bit is also set. The
GIE/GIEH bit of the INTCON register is the global
interrupt enable which enables all non-peripheral
interrupt sources and disables all interrupt sources,
including the peripherals. All interrupts branch to
address 0008h in Compatibility mode.
 2010 Microchip Technology Inc.
Interrupt Priority
The interrupt priority feature is enabled by setting the
IPEN bit of the RCON register. When interrupt priority
is enabled the GIE/GIEH and PEIE/GIEL global interrupt enable bits of Compatibility mode are replaced by
the GIEH high priority, and GIEL low priority, global
interrupt enables. When set, the GIEH bit of the
INTCON register enables all interrupts that have their
associated IPRx register or INTCONx register priority
bit set (high priority). When clear, the GIEH bit disables
all interrupt sources including those selected as low priority. When clear, the GIEL bit of the INTCON register
disables only the interrupts that have their associated
priority bit cleared (low priority). When set, the GIEL bit
enables the low priority sources when the GIEH bit is
also set.
When the interrupt flag, enable bit and appropriate
Global Interrupt Enable (GIE) bit are all set, the
interrupt will vector immediately to address 0008h for
high priority, or 0018h for low priority, depending on
level of the interrupting source’s priority bit. Individual
interrupts can be disabled through their corresponding
interrupt enable bits.
9.3
Interrupt Response
When an interrupt is responded to, the Global Interrupt
Enable bit is cleared to disable further interrupts. The
GIE/GIEH bit is the global interrupt enable when the
IPEN bit is cleared. When the IPEN bit is set, enabling
interrupt priority levels, the GIEH bit is the high priority
global interrupt enable and the GIEL bit is the low
priority global interrupt enable. 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 in the INTCONx and PIRx
registers. The interrupt flag bits must be cleared by
software before re-enabling interrupts to avoid
repeating the same interrupt.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine and sets the GIE/GIEH bit (GIEH
or GIEL if priority levels are used), which re-enables
interrupts.
For external interrupt events, such as the INT pins or
the PORTB interrupt-on-change, the interrupt latency
will be three to four instruction cycles. The exact
latency is the same for one-cycle or two-cycle
Preliminary
DS41412C-page 113
PIC18(L)F2X/4XK22
instructions. Individual interrupt flag bits are set,
regardless of the status of their corresponding enable
bits or the Global Interrupt Enable 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.
FIGURE 9-1:
PIC18 INTERRUPT LOGIC
Wake-up if in
Idle or Sleep modes
INT0IF
INT0IE
PIR1<6:0>
PIE1<6:0>
IPR1<6:0>
PIR2<7:0>
PIE2<7:0>
IPR2<7:0>
PIR3<7:0>
PIE3<7:0>
IPR3<7:0>
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
INT1IF
INT1IE
INT1IP
INT2IF
INT2IE
INT2IP
(1)
Interrupt to CPU
Vector to Location
0008h
GIEH/GIE
IPEN
PIR4<2:0>
PIE4<2:0>
IPR4<2:0>
PIR5<2:0>
PIE5<2:0>
IPR5<2:0>
IPEN
GIEL/PEIE
IPEN
High Priority Interrupt Generation
Low Priority Interrupt Generation
PIR1<6:0>
PIE1<6:0>
IPR1<6:0>
PIR2<7:0>
PIE2<7:0>
IPR2<7:0>
PIR3<7:0>
PIE3<7:0>
IPR3<7:0>
PIR4<2:0>
PIE4<2:0>
IPR4<2:0>
PIR5<2:0>
PIE5<2:0>
IPR5<2:0>
Interrupt to CPU
Vector to Location
0018h
TMR0IF
TMR0IE
TMR0IP
RBIF
RBIE
RBIP
(1)
GIEH/GIE
GIEL/PEIE
INT1IF
INT1IE
INT1IP
INT2IF
INT2IE
INT2IP
Note
1:
The RBIF interrupt also requires the individual pin IOCB enables.
DS41412C-page 114
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
9.4
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
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
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 including peripherals
When IPEN = 1:
1 = Enables all high priority interrupts
0 = Disables all interrupts including low priority
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 interrupts
0 = Disables all low priority 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: Port B Interrupt-On-Change (IOCx) Interrupt Enable bit(2)
1 = Enables the IOCx port change interrupt
0 = Disables the IOCx port change interrupt
bit 2
TMR0IF: TMR0 Overflow Interrupt Flag bit
1 = TMR0 register has overflowed (must be cleared by software)
0 = TMR0 register did not overflow
bit 1
INT0IF: INT0 External Interrupt Flag bit
1 = The INT0 external interrupt occurred (must be cleared by software)
0 = The INT0 external interrupt did not occur
bit 0
RBIF: Port B Interrupt-On-Change (IOCx) Interrupt Flag bit(1)
1 = At least one of the IOC<3:0> (RB<7:4>) pins changed state (must be cleared by software)
0 = None of the IOC<3:0> (RB<7:4>) pins have changed state
Note 1:
2:
A mismatch condition will continue to set the RBIF bit. Reading PORTB will end the
mismatch condition and allow the bit to be cleared.
RB port change interrupts also require the individual pin IOCB enables.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 115
PIC18(L)F2X/4XK22
REGISTER 9-2:
INTCON2: INTERRUPT CONTROL 2 REGISTER
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
x = Bit is unknown
bit 7
RBPU: PORTB Pull-up Enable bit
1 = All PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled provided that the pin is an input and the corresponding WPUB bit is
set.
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:
Interrupt flag bits are set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the global
enable bit. User software should ensure
the appropriate interrupt flag bits are clear
prior to enabling an interrupt. This feature
allows for software polling.
DS41412C-page 116
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 9-3:
INTCON3: INTERRUPT CONTROL 3 REGISTER
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 by 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 by 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
enable bit. User software should ensure
the appropriate interrupt flag bits are clear
prior to enabling an interrupt. This feature
allows for software polling.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 117
PIC18(L)F2X/4XK22
9.5
PIR Registers
The PIR registers contain the individual flag bits for the
peripheral interrupts. Due to the number of peripheral
interrupt sources, there are five Peripheral Interrupt
Request Flag registers (PIR1, PIR2, PIR3, PIR4 and
PIR5).
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/GIEH of
the INTCON register.
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
U-0
R/W-0
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIF
RC1IF
TX1IF
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
Unimplemented: Read as ‘0’.
bit 6
ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared by software)
0 = The A/D conversion is not complete or has not been started
bit 5
RC1IF: EUSART1 Receive Interrupt Flag bit
1 = The EUSART1 receive buffer, RCREG1, is full (cleared when RCREG1 is read)
0 = The EUSART1 receive buffer is empty
bit 4
TX1IF: EUSART1 Transmit Interrupt Flag bit
1 = The EUSART1 transmit buffer, TXREG1, is empty (cleared when TXREG1 is written)
0 = The EUSART1 transmit buffer is full
bit 3
SSP1IF: Master Synchronous Serial Port 1 Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared by software)
0 = Waiting to transmit/receive
bit 2
CCP1IF: CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared by software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared by 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 by software)
0 = No TMR2 to PR2 match occurred
bit 0
TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared by software)
0 = TMR1 register did not overflow
DS41412C-page 118
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 9-5:
PIR2: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 2
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
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 HFINTOSC (must be cleared by software)
0 = Device clock operating
bit 6
C1IF: Comparator C1 Interrupt Flag bit
1 = Comparator C1 output has changed (must be cleared by software)
0 = Comparator C1 output has not changed
bit 5
C2IF: Comparator C2 Interrupt Flag bit
1 = Comparator C2 output has changed (must be cleared by software)
0 = Comparator C2 output has not changed
bit 4
EEIF: Data EEPROM/Flash Write Operation Interrupt Flag bit
1 = The write operation is complete (must be cleared by software)
0 = The write operation is not complete or has not been started
bit 3
BCL1IF: MSSP1 Bus Collision Interrupt Flag bit
1 = A bus collision occurred (must be cleared by software)
0 = No bus collision occurred
bit 2
HLVDIF: Low-Voltage Detect Interrupt Flag bit
1 = A low-voltage condition occurred (direction determined by the VDIRMAG bit of the
HLVDCON register)
0 = A low-voltage condition has not occurred
bit 1
TMR3IF: TMR3 Overflow Interrupt Flag bit
1 = TMR3 register overflowed (must be cleared by software)
0 = TMR3 register did not overflow
bit 0
CCP2IF: CCP2 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared by software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared by software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 119
PIC18(L)F2X/4XK22
REGISTER 9-6:
PIR3: PERIPHERAL INTERRUPT (FLAG) REGISTER 3
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
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
SSP2IF: Synchronous Serial Port Interrupt Flag bit
1 = The transmission/reception is complete (must be cleared in software)
0 = Waiting to transmit/receive
bit 6
BCL2IF: MSSP2 Bus Collision Interrupt Flag bit
1 = A bus collision has occurred while the SSP2 module configured in I2C master was transmitting
(must be cleared in software)
0 = No bus collision occurred
bit 5
RC2IF: EUSART2 Receive Interrupt Flag bit
1 = The EUSART2 receive buffer, RCREG2, is full (cleared by reading RCREG2)
0 = The EUSART2 receive buffer is empty
bit 4
TX2IF: EUSART2 Transmit Interrupt Flag bit
1 = The EUSART2 transmit buffer, TXREG2, is empty (cleared by writing TXREG2)
0 = The EUSART2 transmit buffer is full
bit 3
CTMUIF: CTMU Interrupt Flag bit
1 = CTMU interrupt occurred (must be cleared in software)
0 = No CTMU interrupt occurred
bit 2
TMR5GIF: TMR5 Gate Interrupt Flag bits
1 = TMR gate interrupt occurred (must be cleared in software)
0 = No TMR gate occurred
bit 1
TMR3GIF: TMR3 Gate Interrupt Flag bits
1 = TMR gate interrupt occurred (must be cleared in software)
0 = No TMR gate occurred
bit 0
TMR1GIF: TMR1 Gate Interrupt Flag bits
1 = TMR gate interrupt occurred (must be cleared in software)
0 = No TMR gate occurred
DS41412C-page 120
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 9-7:
PIR4: PERIPHERAL INTERRUPT (FLAG) REGISTER 4
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
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 7-3
Unimplemented: Read as ‘0’
bit 2
CCP5IF: CCP5 Interrupt Flag bits
Capture mode:
1 = A TMR register capture occurred (must be cleared in software)
0 = No TMR register capture occurred
Compare mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM mode:
Unused in PWM mode.
bit 1
CCP4IF: CCP4 Interrupt Flag bits
Capture mode:
1 = A TMR register capture occurred (must be cleared in software)
0 = No TMR register capture occurred
Compare mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM mode:
Unused in PWM mode.
bit 0
CCP3IF: ECCP3 Interrupt Flag bits
Capture mode:
1 = A TMR register capture occurred (must be cleared in software)
0 = No TMR register capture occurred
Compare mode:
1 = A TMR register compare match occurred (must be cleared in software)
0 = No TMR register compare match occurred
PWM mode:
Unused in PWM mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 121
PIC18(L)F2X/4XK22
REGISTER 9-8:
PIR5: PERIPHERAL INTERRUPT (FLAG) REGISTER 5
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
TMR6IF
TMR5IF
TMR4IF
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 7-3
Unimplemented: Read as ‘0’
bit 2
TMR6IF: TMR6 to PR6 Match Interrupt Flag bit
1 = TMR6 to PR6 match occurred (must be cleared in software)
0 = No TMR6 to PR6 match occurred
bit 1
TMR5IF: TMR5 Overflow Interrupt Flag bit
1 = TMR5 register overflowed (must be cleared in software)
0 = TMR5 register did not overflow
bit 0
TMR4IF: TMR4 to PR4 Match Interrupt Flag bit
1 = TMR4 to PR4 match occurred (must be cleared in software)
0 = No TMR4 to PR4 match occurred
DS41412C-page 122
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
9.6
PIE Registers
The PIE registers contain the individual enable bits for
the peripheral interrupts. Due to the number of
peripheral interrupt sources, there are five Peripheral
Interrupt Enable registers (PIE1, PIE2, PIE3, PIE4 and
PIE5). When IPEN = 0, the PEIE/GIEL bit must be set to
enable any of these peripheral interrupts.
REGISTER 9-9:
PIE1: PERIPHERAL INTERRUPT ENABLE (FLAG) REGISTER 1
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIE
RC1IE
TX1IE
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
Unimplemented: Read as ‘0’.
bit 6
ADIE: A/D Converter Interrupt Enable bit
1 = Enables the A/D interrupt
0 = Disables the A/D interrupt
bit 5
RC1IE: EUSART1 Receive Interrupt Enable bit
1 = Enables the EUSART1 receive interrupt
0 = Disables the EUSART1 receive interrupt
bit 4
TX1IE: EUSART1 Transmit Interrupt Enable bit
1 = Enables the EUSART1 transmit interrupt
0 = Disables the EUSART1 transmit interrupt
bit 3
SSP1IE: Master Synchronous Serial Port 1 Interrupt Enable bit
1 = Enables the MSSP1 interrupt
0 = Disables the MSSP1 interrupt
bit 2
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the 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
 2010 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41412C-page 123
PIC18(L)F2X/4XK22
REGISTER 9-10:
PIE2: PERIPHERAL INTERRUPT ENABLE (FLAG) REGISTER 2
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
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
C1IE: Comparator C1 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 5
C2IE: Comparator C2 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 4
EEIE: Data EEPROM/Flash Write Operation Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 3
BCL1IE: MSSP1 Bus Collision Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2
HLVDIE: Low-Voltage Detect Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1
TMR3IE: TMR3 Overflow Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0
CCP2IE: CCP2 Interrupt Enable bit
1 = Enabled
0 = Disabled
DS41412C-page 124
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 9-11:
PIE3: PERIPHERAL INTERRUPT ENABLE (FLAG) REGISTER 3
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
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: TMR5 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 6
BCL2IE: Bus Collision Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 5
RC2IE: EUSART2 Receive Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 4
TX2IE: EUSART2 Transmit Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 3
CTMUIE: CTMU Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2
TMR5GIE: TMR5 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1
TMR3GIE: TMR3 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0
TMR1GIE: TMR1 Gate Interrupt Enable bit
1 = Enabled
0 = Disabled
 2010 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41412C-page 125
PIC18(L)F2X/4XK22
REGISTER 9-12:
PIE4: PERIPHERAL INTERRUPT ENABLE (FLAG) REGISTER 4
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
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 7-3
Unimplemented: Read as ‘0’
bit 2
CCP5IE: CCP5 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1
CCP4IE: CCP4 Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0
CCP3IE: CCP3 Interrupt Enable bit
1 = Enabled
0 = Disabled
REGISTER 9-13:
x = Bit is unknown
PIE5: PERIPHERAL INTERRUPT ENABLE (FLAG) REGISTER 5
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
TMR6IE
TMR5IE
TMR4IE
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 7-3
Unimplemented: Read as ‘0’
bit 2
TMR6IE: TMR6 to PR6 Match Interrupt Enable bit
1 = Enables the TMR6 to PR6 match interrupt
0 = Disables the TMR6 to PR6 match interrupt
bit 1
TMR5IE: TMR5 Overflow Interrupt Enable bit
1 = Enables the TMR5 overflow interrupt
0 = Disables the TMR5 overflow interrupt
bit 0
TMR4IE: TMR4 to PR4 Match Interrupt Enable bit
1 = Enables the TMR4 to PR4 match interrupt
0 = Disables the TMR4 to PR4 match interrupt
DS41412C-page 126
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
9.7
IPR Registers
The IPR registers contain the individual priority bits for the
peripheral interrupts. Due to the number of peripheral
interrupt sources, there are five Peripheral Interrupt
Priority registers (IPR1, IPR2, IPR3, IPR4 and IPR5).
Using the priority bits requires that the Interrupt Priority
Enable (IPEN) bit be set.
REGISTER 9-14:
IPR1: PERIPHERAL INTERRUPT PRIORITY REGISTER 1
U-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
—
ADIP
RC1IP
TX1IP
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
Unimplemented: Read as ‘0’
bit 6
ADIP: A/D Converter Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
RC1IP: EUSART1 Receive Interrupt Priority bit
1 = High priority
0 = Low priority
bit 4
TX1IP: EUSART1 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: 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
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 127
PIC18(L)F2X/4XK22
REGISTER 9-15:
IPR2: PERIPHERAL INTERRUPT PRIORITY REGISTER 2
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
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
C1IP: Comparator C1 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
C2IP: Comparator C2 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 4
EEIP: Data EEPROM/Flash Write Operation Interrupt Priority bit
1 = High priority
0 = Low priority
bit 3
BCL1IP: MSSP1 Bus Collision Interrupt Priority bit
1 = High priority
0 = Low priority
bit 2
HLVDIP: Low-Voltage Detect Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR3IP: TMR3 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
CCP2IP: CCP2 Interrupt Priority bit
1 = High priority
0 = Low priority
DS41412C-page 128
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 9-16:
IPR3: PERIPHERAL INTERRUPT PRIORITY REGISTER 3
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
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: Synchronous Serial Port 2 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 6
BCL2IP: Bus Collision 2 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 5
RC2IP: EUSART2 Receive Interrupt Priority bit
1 = High priority
0 = Low priority
bit 4
TX2IP: EUSART2 Transmit Interrupt Priority bit
1 = High priority
0 = Low priority
bit 3
CTMUIP: CTMU Interrupt Priority bit
1 = High priority
0 = Low priority
bit 2
TMR5GIP: TMR5 Gate Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR3GIP: TMR3 Gate Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
TMR1GIP: TMR1 Gate Interrupt Priority bit
1 = High priority
0 = Low priority
 2010 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41412C-page 129
PIC18(L)F2X/4XK22
REGISTER 9-17:
IPR4: PERIPHERAL INTERRUPT PRIORITY REGISTER 4
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
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 7-3
Unimplemented: Read as ‘0’
bit 2
CCP5IP: CCP5 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
CCP4IP: CCP4 Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
CCP3IP: CCP3 Interrupt Priority bit
1 = High priority
0 = Low priority
REGISTER 9-18:
x = Bit is unknown
IPR5: PERIPHERAL INTERRUPT PRIORITY REGISTER 5
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
—
—
—
—
—
TMR6IP
TMR5IP
TMR4IP
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 7-3
Unimplemented: Read as ‘0’
bit 2
TMR6IP: TMR6 to PR6 Match Interrupt Priority bit
1 = High priority
0 = Low priority
bit 1
TMR5IP: TMR5 Overflow Interrupt Priority bit
1 = High priority
0 = Low priority
bit 0
TMR4IP: TMR4 to PR4 Match Interrupt Priority bit
1 = High priority
0 = Low priority
DS41412C-page 130
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
9.8
INTn Pin Interrupts
9.9
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, INTxF, is set. This interrupt can be disabled by
clearing the corresponding enable bit, INTxE. Flag bit,
INTxF, must be cleared by software in the Interrupt
Service Routine before re-enabling the interrupt.
All external interrupts (INT0, INT1 and INT2) can wakeup the processor from Idle or Sleep modes if bit INTxE
was set prior to going into those modes. If the Global
Interrupt Enable bit, GIE/GIEH, 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
and INT2IP of the INTCON3 register. 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 of the INTCON register. Interrupt priority for
Timer0 is determined by the value contained in the
interrupt priority bit, TMR0IP of the INTCON2 register.
See Section 11.0 “Timer0 Module” for further details
on the Timer0 module.
9.10
PORTB Interrupt-on-Change
An input change on PORTB<7:4> sets flag bit, RBIF of
the INTCON register. The interrupt can be enabled/
disabled by setting/clearing enable bit, RBIE of the
INTCON register. Pins must also be individually
enabled with the IOCB register. Interrupt priority for
PORTB interrupt-on-change is determined by the value
contained in the interrupt priority bit, RBIP of the
INTCON2 register.
9.11
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 5.1.3
“Fast Register Stack”), 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
 2010 Microchip Technology Inc.
; W_TEMP is in virtual bank
; STATUS_TEMP located anywhere
; BSR_TMEP located anywhere
; Restore BSR
; Restore WREG
; Restore STATUS
Preliminary
DS41412C-page 131
PIC18(L)F2X/4XK22
TABLE 9-1:
Name
ANSELB
INTCON
REGISTERS ASSOCIATED WITH INTERRUPTS
Bit 7
Bit 6
—
—
GIE/GIEH PEIE/GIEL
Bit 2
Bit 1
Bit 0
Register
on Page
ANSB3
ANSB2
ANSB1
ANSB0
153
RBIE
TMR0IF
INT0IF
RBIF
115
—
TMR0IP
—
RBIP
116
INT1IE
—
INT2IF
INT1IF
117
Bit 5
Bit 4
Bit 3
ANSB5
ANSB4
TMR0IE
INT0IE
INTCON2
RBPU
INTEDG0
INTCON3
INT2IP
INT1IP
INTEDG1 INTEDG2
—
INT2IE
IOCB
IOCB7
IOCB6
IOCB5
IOCB4
—
—
—
—
156
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP TMR5GIP TMR3GIP TMR1GIP
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
130
IPR5
—
—
—
—
—
TMR6IP
TMR5IP
TMR4IP
130
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE TMR5GIE TMR3GIE TMR1GIE
PIE4
—
—
—
—
PIE5
—
—
—
PIR1
—
ADIF
RC1IF
PIR2
OSCFIF
C1IF
C2IF
PIR3
SSP2IF
BCL2IF
RC2IF
PIR4
—
—
—
—
—
CCP5IF
PIR5
—
—
—
—
—
TMR6IF
129
125
—
CCP5IE
CCP4IE
CCP3IE
126
—
—
TMR6IE
TMR5IE
TMR4IE
126
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
EEIF
BCL1IF
HLVDIF
TMR3IF
TX2IF
CTMUIF TMR5GIF TMR3GIF
CCP2IF
119
TMR1GIF
120
CCP4IF
CCP3IF
121
TMR5IF
TMR4IF
122
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
151
RCON
IPEN
SBOREN
—
RI
TO
PD
POR
BOR
60
Legend:
— = unimplemented locations, read as ‘0’. Shaded bits are not used for Interrupts.
TABLE 9-2:
CONFIGURATION REGISTERS ASSOCIATED WITH INTERRUPTS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
CONFIG4L
DEBUG
XINST
—
—
—
LVP
—
STRVEN
355
Legend:
— = unimplemented locations, read as ‘0’. Shaded bits are not used for Interrupts.
DS41412C-page 132
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
10.0
I/O PORTS
10.1
Depending on the device selected and features
enabled, there are up to five ports available. All pins of
the I/O ports are multiplexed with one or more alternate
functions 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.
Each port has five registers for its operation. These
registers are:
• TRIS register (data direction register)
• PORT register (reads the levels on the pins of the
device)
• LAT register (output latch)
• ANSEL register (analog input control)
• SLRCON register (port slew rate control)
The Data Latch (LAT register) is useful for read-modifywrite operations on the value that the I/O pins are
driving.
A simplified model of a generic I/O port, without the
interfaces to other peripherals, is shown in Figure 10-1.
FIGURE 10-1:
GENERIC I/O PORT
OPERATION
Data
Bus
WR LAT
or Port
D
Q
I/O pin(1)
CK
Data Latch
D
WR TRIS
PORTA is an 8-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., disable the output driver). Clearing a
TRISA bit (= 0) will make the corresponding PORTA pin
an output (i.e., enable the output driver and 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 RA4 pin is multiplexed with the Timer0 module
clock input and one of the comparator outputs to
become the RA4/T0CKI/C1OUT pin. Pins RA6 and
RA7 are multiplexed with the main oscillator pins; they
are enabled as oscillator or I/O pins by the selection of
the main oscillator in the Configuration register (see
Section 24.1 “Configuration Bits” for details). When
they are not used as port pins, RA6 and RA7 and their
associated TRIS and LAT bits are read as ‘0’.
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 analog is selected by setting
the ANSELA<5, 3:0> bits in the ANSELA register which
is the default setting after a Power-on Reset.
TRISx
RD LAT
Pins RA0 through RA5 may also be used as comparator
inputs or outputs by setting the appropriate bits in the
CM1CON0 and CM2CON0 registers.
Note:
Q
ANSELx
CK
TRIS Latch
Input
Buffer
RD TRIS
Q
D
PORTA Registers
On a Power-on Reset, RA5 and RA<3:0>
are configured as analog inputs and read
as ‘0’. RA4 is configured as a digital input.
The RA4/T0CKI/C1OUT pin is a Schmitt Trigger input.
All other PORTA pins have TTL input levels and full
CMOS output drivers.
The TRISA register controls the drivers of the PORTA
pins, even when they are being used as analog inputs.
The user should ensure the bits in the TRISA register
are maintained set when using them as analog inputs.
ENEN
EXAMPLE 10-1:
RD Port
Note 1:
I/O pins have diode protection to VDD and VSS.
MOVLB
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
 2010 Microchip Technology Inc.
Preliminary
0xF
PORTA
;
;
;
;
LATA
;
;
;
E0h
;
ANSELA ;
0CFh
;
;
;
TRISA
;
;
INITIALIZING PORTA
Set BSR for banked SFRs
Initialize PORTA by
clearing output
data latches
Alternate method
to clear output
data latches
Configure I/O
for digital inputs
Value used to
initialize data
direction
Set RA<3:0> as inputs
RA<5:4> as outputs
DS41412C-page 133
PIC18(L)F2X/4XK22
TABLE 10-1:
PORTA I/O SUMMARY
Pin Name
Function
RA0/C12IN0-/AN0
RA0
RA1/C12IN1-/AN1
RA2/C2IN+/AN2/
DACOUT/VREF-
RA3/C1IN+/AN3/
VREF+
RA4/CCP5/
C1OUT/SRQ/
T0CKI
RA5/C2OUT/
SRNQ/SS1/
HLVDIN/AN4
TRIS ANSEL
Setting Setting
Buffer
Type
Description
0
1
O
DIG
LATA<0> data output; not affected by analog input.
1
0
I
TTL
PORTA<0> data input; disabled when analog input
enabled.
C12IN0-
1
1
I
AN
Comparators C1 and C2 inverting input.
AN0
1
1
I
AN
Analog input 0.
RA1
0
1
O
DIG
LATA<1> data output; not affected by analog input.
1
0
I
TTL
PORTA<1> data input; disabled when analog input
enabled.
C12IN1-
1
1
I
AN
Comparators C1 and C2 inverting input.
AN1
1
1
I
AN
Analog input 1.
RA2
0
1
O
DIG
LATA<2> data output; not affected by analog input; disabled
when DACOUT enabled.
1
0
I
TTL
PORTA<2> data input; disabled when analog input
enabled; disabled when DACOUT enabled.
C2IN+
1
1
I
AN
Comparator C2 non-inverting input.
AN2
1
1
I
AN
Analog output 2.
DACOUT
x
1
O
AN
DAC Reference output.
VREF-
1
1
I
AN
A/D reference voltage (low) input.
RA3
0
1
O
DIG
LATA<3> data output; not affected by analog input.
1
0
I
TTL
PORTA<3> data input; disabled when analog input enabled.
C1IN+
1
1
I
AN
Comparator C1 non-inverting input.
AN3
1
1
I
AN
Analog input 3.
VREF+
1
1
I
AN
A/D reference voltage (high) input.
RA4
0
1
O
DIG
LATA<4> data output.
1
0
I
TTL
PORTA<4> data input; default configuration on POR.
0
1
O
DIG
CCP5 Compare output/PWM output, takes priority over
RA4 output.
CCP5
1
0
I
ST
Capture 5 input/Compare 5 output/ PWM 5 output.
C1OUT
0
1
O
DIG
Comparator C1 output.
SR Latch Q output; take priority over CCP 5 output.
SRQ
0
1
O
DIG
T0CKI
1
0
I
ST
Timer0 external clock input.
RA5
0
1
O
DIG
LATA<5> data output; not affected by analog input.
1
0
I
TTL
PORTA<5> data input; disabled when analog input enabled.
0
1
O
DIG
Comparator C2 output.
1
O
DIG
SR Latch Q output.
C2OUT
SRNQ
Legend:
Pin
Type
SS1
1
0
I
TTL
SPI slave select input (MSSP1).
HLVDIN
1
1
I
AN
High/Low-Voltage Detect input.
AN4
1
1
I
AN
A/D input 4.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS
= CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with
I2C.
DS41412C-page 134
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-1:
PORTA I/O SUMMARY (CONTINUED)
Pin Name
RA6/CLKO/OSC2
RA6
RA7/CLKI/OSC1
Legend:
TRIS ANSEL
Setting Setting
Function
Pin
Type
Buffer
Type
Description
0
1
O
DIG
LATA<6> data output; enabled in INTOSC modes when
CLKO is not enabled.
1
0
I
TTL
PORTA<6> data input; enabled in INTOSC modes when
CLKO is not enabled.
CLKO
x
1
O
DIG
In RC mode, OSC2 pin outputs CLKOUT which has 1/4 the
frequency of OSC1 and denotes the instruction cycle rate.
OSC2
x
x
O
XTAL
Oscillator crystal output; connects to crystal or resonator in
Crystal Oscillator mode.
RA7
0
1
O
DIG
LATA<7> data output; disabled in external oscillator modes.
1
0
I
TTL
PORTA<7> data input; disabled in external oscillator
modes.
CLKI
x
1
I
AN
External clock source input; always associated with pin
function OSC1.
OSC1
x
x
I
XTAL
Oscillator crystal input or external clock source input ST
buffer when configured in RC mode; CMOS otherwise.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS
= CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with
I2C.
TABLE 10-2:
Name
ANSELA
CM1CON0
REGISTERS ASSOCIATED WITH PORTA
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
—
—
C1ON
C1OUT
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
C1OE
C1POL
C1SP
C1R
C2SP
C2R
CM2CON0
C2ON
C2OUT
C2OE
C2POL
VREFCON1
DACEN
DACLPS
DACOE
—
VREFCON2
HLVDCON
PORTA
—
—
—
VDIRMAG
BGVST
IRVST
C1CH<1:0>
C2CH<1:0>
DACPSS<1:0>
—
DACNSS
DACR<4:0>
HLVDEN
Register
on Page
152
310
311
341
342
HLVDL<3:0>
343
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
151
SLRCON
—
—
—
SLRE
SLRD
SLRC
SLRB
SLRA
156
SRCON0
SRLEN
SRQEN
SRNQEN
SRPS
SRPR
335
SSP1CON1
WCOL
SRCLK<2:0>
SSPOV
SSPEN
CKP
SSPM<3:0>
T0CON
TMR0ON
T08BIT
T0CS
T0SE
PSA
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
256
T0PS<2:0>
TRISA2
TRISA1
157
TRISA0
154
Bit 0
Register
on Page
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTA.
TABLE 10-3:
CONFIGURATION REGISTERS ASSOCIATED WITH PORTA
Name
Bit 7
Bit 6
CONFIG1H
IESO
FCMEN
Bit 5
Bit 4
Bit 3
PRICLKEN PLLCFG
Bit 2
Bit 1
FOSC<3:0>
351
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTA.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 135
PIC18(L)F2X/4XK22
10.1.1
PORTA OUTPUT PRIORITY
Each PORTA pin is multiplexed with other functions.
The pins, their combined functions and their output
priorities are briefly described here. For additional
information, refer to the appropriate section in this data
sheet.
When multiple outputs are enabled, the actual pin
control goes to the peripheral with the higher priority.
Table 10-4 lists the PORTA pin functions from the
highest to the lowest priority.
Analog input functions, such as ADC and comparator,
are not shown in the priority lists.
These inputs are active when the I/O pin is set for
Analog mode using the ANSELx registers. Digital
output functions may control the pin when it is in Analog
mode with the priority shown below.
TABLE 10-4:
PORT PIN FUNCTION PRIORITY
Port bit
0
1
Port Function Priority by Port Pin
PORTA
PORTB
PORTC
PORTD(2)
PORTE(2)
RA0
CCP4(1)
SOSCO
SCL2
CCP3(8)
RB0
P2B(6)
SCK2
P3A(8)
RC0
RD0
RE0
RA1
2
RA2
SCL2(1)
SOSCI
SDA2
P3B
SCK2(1)
CCP2(3)
CCP4
RE1
P1C(1)
P2A(3)
RD1
RB1
RC1
SDA2(1)
CCP1
P2B
CCP5
P1B(1)
P1A
RD2(4)
RE2
RB2
CTPLS
RC2
3
RA3
(1)
SCL1
P2C
MCLR
CCP2(6)
SCK1
RD3
VPP
P2A(6)
RC3
SDO2
RE3
RB3
4
SRQ
P1D(1)
SDA1
SDO2
C1OUT
RB4
RC4
P2D
(1)
RD4
CCP5
RA4
Note 1:
2:
3:
4:
5:
6:
7:
8:
PIC18(L)F2XK22 devices.
PIC18(L)F4XK22 devices.
Function default pin.
Function default pin (28-pin devices).
Function default pin (40/44-pin devices).
Function alternate pin.
Function alternate pin (28-pin devices).
Function alternate pin (40/44-pin devices)
DS41412C-page 136
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-4:
Port bit
5
PORT PIN FUNCTION PRIORITY (CONTINUED)
Port Function Priority by Port Pin
PORTD(2)
PORTA
PORTB
PORTC
SRNQ
CCP3(3)
SDO1
P1B
C2OUT
P3A(3)
RC5
RD5
RA5
P2B(1)(4)
PORTE(2)
RB5
6
OSC2
PGC
TX1/CK1
TX2/CK2
CLKO
TX2/CK2(1)
CCP3(1)(7)
P1C
RB6
P3A(1)(7)
RD6
ICDCK
RC6
RA6
7
RA7
OSC1
RA7
PGD
RX2/DT2
RX1/DT1
(1)
RB7
RX2/DT2
P3B(1)
P1D
RC7
RD7
ICDDT
Note 1:
2:
3:
4:
5:
6:
7:
8:
PIC18(L)F2XK22 devices.
PIC18(L)F4XK22 devices.
Function default pin.
Function default pin (28-pin devices).
Function default pin (40/44-pin devices).
Function alternate pin.
Function alternate pin (28-pin devices).
Function alternate pin (40/44-pin devices)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 137
PIC18(L)F2X/4XK22
10.2
PORTB Registers
10.3
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., disable the output driver). Clearing a
TRISB bit (= 0) will make the corresponding PORTB
pin an output (i.e., enable the output driver and 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 10-2:
MOVLB
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
10.2.1
0xF
PORTB
;
;
;
;
LATB
;
;
;
0F0h
;
ANSELB ;
;
;
;
0CFh
;
;
;
TRISB
;
;
;
INITIALIZING PORTB
Set BSR for banked SFRs
Initialize PORTB by
clearing output
data latches
Alternate method
to clear output
data latches
Value for init
Enable RB<3:0> for
digital input pins
(not required if config bit
PBADEN is clear)
Value used to
initialize data
direction
Set RB<3:0> as inputs
RB<5:4> as outputs
RB<7:6> as inputs
PORTB OUTPUT PRIORITY
Each PORTB pin is multiplexed with other functions.
The pins, their combined functions and their output
priorities are briefly described here. For additional
information, refer to the appropriate section in this data
sheet.
When multiple outputs are enabled, the actual pin
control goes to the peripheral with the higher priority.
Table 10-4 lists the PORTB pin functions from the
highest to the lowest priority.
Analog input functions, such as ADC, comparator and
SR Latch inputs, are not shown in the priority lists.
These inputs are active when the I/O pin is set for
Analog mode using the ANSELx registers. Digital
output functions may control the pin when it is in Analog
mode with the priority shown below.
DS41412C-page 138
Additional PORTB Pin Functions
PORTB pins RB<7:4> have an interrupt-on-change
option. All PORTB pins have a weak pull-up option.
10.3.1
WEAK PULL-UPS
Each of the PORTB pins has an individually controlled
weak internal pull-up. When set, each bit of the WPUB
register enables the corresponding pin pull-up. When
cleared, the RBPU bit of the INTCON2 register enables
pull-ups on all pins which also have their corresponding
WPUB bit set. When set, the RBPU bit disables all
weak pull-ups. 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:
On a Power-on Reset, RB<5:0> are
configured as analog inputs by default and
read as ‘0’; RB<7:6> are configured as
digital inputs.
When the PBADEN Configuration bit is set
to ‘1’, RB<5:0> will alternatively be
configured as digital inputs on POR.
10.3.2
INTERRUPT-ON-CHANGE
Four of the PORTB pins (RB<7:4>) are individually
configurable as interrupt-on-change pins. Control bits
in the IOCB register enable (when set) or disable (when
clear) the interrupt function for each pin.
When set, the RBIE bit of the INTCON register enables
interrupts on all pins which also have their
corresponding IOCB bit set. When clear, the RBIE bit
disables all interrupt-on-changes.
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 interrupt-on-change comparison).
For enabled interrupt-on-change pins, the values are
compared with the old value latched on the last read of
PORTB. The ‘mismatch’ outputs of the last read are
OR’d together to set the PORTB Change Interrupt flag
bit (RBIF) in the INTCON register.
This interrupt can wake the device from the 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)
Preliminary
Any read or write of PORTB to clear the mismatch condition (except when PORTB is the
source or destination of a MOVFF instruction).
Execute at least one instruction after reading or
writing PORTB, then clear the flag bit, RBIF.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
10.3.3
A mismatch condition will continue to set the RBIF flag bit.
Reading or writing PORTB will end the mismatch
condition and allow the RBIF bit to be cleared. The latch
holding the last read value is not affected by a MCLR nor
Brown-out Reset. After either one of these Resets, the
RBIF flag will continue to be set if a mismatch is present.
Note:
ALTERNATE FUNCTIONS
PORTB is multiplexed with several peripheral functions
(Table 10-5). The pins have TTL input buffers. Some of
these pin functions can be relocated to alternate pins
using the Control fuse bits in CONFIG3H. RB5 is the
default pin for P2B (28-pin devices). Clearing the
P2BMX bit moves the pin function to RC0. RB5 is also
the default pin for the CCP3/P3A peripheral pin. Clearing the CCP3MX bit moves the pin function to the RC6
pin (28-pin devices) or RE0 (40/44-pin devices).
If a change on the I/O pin should occur
when the read operation is being executed
(start of the Q2 cycle), then the RBIF
interrupt flag may not get set. Furthermore,
since a read or write on a port affects all bits
of that port, care must be taken when using
multiple pins in Interrupt-on-change mode.
Changes on one pin may not be seen while
servicing changes on another pin.
Two other pin functions, T3CKI and CCP2/P2A, can be
relocated from their default pins to PORTB pins by
clearing the control fuses in CONFIG3H. Clearing
T3CMX and CCP2MX moves the pin functions to RB5
and RB3, respectively.
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.
TABLE 10-5:
Pin
PORTB I/O SUMMARY
Function
RB0/INT0/CCP4/
FLT0/SRI/SS2/
AN12
RB0
Note 1:
2:
3:
Buffer
Type
Description
0
1
O
DIG
LATB<0> data output; not affected by analog input.
1
0
I
TTL
PORTB<0> data input; disabled when analog input
enabled.
INT0
1
I
ST
External interrupt 0.
0
1
O
DIG
Compare 4 output/PWM 4 output.
1
0
I
ST
Capture 4 input.
1
0
I
ST
PWM Fault input for ECCP auto-shutdown.
0
SRI
1
0
I
ST
SR Latch input.
SS2(3)
1
0
I
TTL
SPI slave select input (MSSP2).
AN12
1
1
I
AN
Analog input 12.
RB1
0
1
O
DIG
LATB<1> data output; not affected by analog input.
1
0
I
ST
PORTB<1> data input; disabled when analog input
enabled.
INT1
1
0
I
ST
External Interrupt 1.
P1C(3)
0
1
O
DIG
Enhanced CCP1 PWM output 3.
SCK2(3)
0
1
O
DIG
MSSP2 SPI Clock output.
1
0
I
ST
MSSP2 SPI Clock input.
0
1
O
DIG
MSSP2 I2CTM Clock output.
1
0
I
I2C
MSSP2 I2CTM Clock input.
C12IN3-
1
1
I
AN
Comparators C1 and C2 inverting input.
AN10
1
1
I
AN
Analog input 10.
SCL2(3)
Legend:
Pin
Type
CCP4(3)
FLT0
RB1/INT1/P1C/
SCK2/SCL2/
C12IN3-/AN10
TRIS ANSEL
Setting Setting
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS =
CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Function on PORTD and PORTE for PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 139
PIC18(L)F2X/4XK22
TABLE 10-5:
PORTB I/O SUMMARY (CONTINUED)
Pin
Function
RB2/INT2/CTED1/
P1B/SDI2/SDA2/
AN8
RB2
RB4/IOC0/P1D/
T5G/AN11
RB5/IOC1/P2B/
P3A/CCP3/T3CKI/
T1G/AN13
Legend:
Note 1:
2:
3:
Pin
Type
Buffer
Type
Description
0
1
O
DIG
LATB<2> data output; not affected by analog input.
1
0
I
ST
PORTB<2> data input; disabled when analog input
enabled.
External interrupt 2.
INT2
1
0
I
ST
CTED1
1
0
I
ST
CTMU Edge 1 input.
P1B(3)
0
1
O
DIG
Enhanced CCP1 PWM output 2.
SDI2(3)
1
0
I
ST
MSSP2 SPI data input.
(3)
0
0
O
DIG
MSSP2 I2CTM data output.
I
I2C
MSSP2 I2CTM data input.
SDA2
RB3/CTED2/P2A/
CCP2/SDO2/
C12IN2-/AN9
TRIS ANSEL
Setting Setting
1
0
AN8
1
1
I
AN
Analog input 8.
RB3
0
1
O
DIG
LATB<3> data output; not affected by analog input.
1
0
I
ST
PORTB<3> data input; disabled when analog input
enabled.
CTED2
1
0
I
ST
CTMU Edge 2 input.
P2A
0
1
O
DIG
Enhanced CCP1 PWM output 1.
CCP2(2)
0
1
O
DIG
Compare 2 output/PWM 2 output.
1
0
I
ST
Capture 2 input.
SDO2(2)
0
1
O
DIG
MSSP2 SPI data output.
C12IN2-
1
1
I
AN
Comparators C1 and C2 inverting input.
AN9
1
1
I
AN
Analog input 9.
RB4
0
1
O
DIG
LATB<4> data output; not affected by analog input.
1
0
I
ST
PORTB<4> data input; disabled when analog input
enabled.
IOC0
1
0
I
TTL
Interrupt-on-change pin.
P1D
0
1
O
DIG
Enhanced CCP1 PWM output 4.
T5G
1
0
I
ST
Timer5 external clock gate input.
AN11
1
1
I
AN
Analog input 11.
RB5
0
1
O
DIG
LATB<5> data output; not affected by analog input.
1
0
I
ST
PORTB<5> data input; disabled when analog input
enabled.
IOC1
1
0
I
TTL
Interrupt-on-change pin 1.
P2B(1)(3)
0
1
O
DIG
Enhanced CCP2 PWM output 2.
P3A(1)
0
1
O
DIG
Enhanced CCP3 PWM output 1.
CCP3(1)
0
1
O
DIG
Compare 3 output/PWM 3 output.
1
0
I
ST
Capture 3 input.
T3CKI(2)
1
0
I
ST
Timer3 clock input.
T1G
1
0
I
ST
Timer1 external clock gate input.
AN13
1
1
I
AN
Analog input 13.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS =
CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Function on PORTD and PORTE for PIC18(L)F4XK22 devices.
DS41412C-page 140
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-5:
PORTB I/O SUMMARY (CONTINUED)
Pin
Function
RB6/KBI2/PGC
TRIS ANSEL
Setting Setting
RB6
2:
3:
ANSELB
ECCP2AS
O
DIG
LATB<6> data output; not affected by analog input.
1
0
I
ST
PORTB<6> data input; disabled when analog input
enabled.
1
0
I
TTL
Interrupt-on-change pin.
0
1
O
DIG
EUSART 2 asynchronous transmit data output.
CK2(3)
0
1
O
DIG
EUSART 2 synchronous serial clock output.
1
0
I
ST
EUSART 2 synchronous serial clock input.
PGC
x
x
I
ST
In-Circuit Debugger and ICSPTM programming clock input.
RB7
0
1
O
DIG
LATB<7> data output; not affected by analog input.
1
0
I
ST
PORTB<7> data input; disabled when analog input
enabled.
IOC3
1
0
I
TTL
Interrupt-on-change pin.
RX2(2), (3)
1
0
I
ST
EUSART 2 asynchronous receive data input.
DT2(2), (3)
0
1
O
DIG
EUSART 2 synchronous serial data output.
1
0
I
ST
EUSART 2 synchronous serial data input.
x
x
O
DIG
In-Circuit Debugger and ICSPTM programming data output.
x
x
I
ST
In-Circuit Debugger and ICSPTM programming data input.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
ANSB0
153
CCP2ASE
CCP2AS<2:0>
P2M<1:0>
CCP3ASE
CCP3CON
INTCON
1
REGISTERS ASSOCIATED WITH PORTB
CCP2CON
ECCP3AS
0
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS =
CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Function on PORTD and PORTE for PIC18(L)F4XK22 devices.
TABLE 10-6:
Name
Description
IOC2
PGD
Note 1:
Buffer
Type
TX2(3)
RB7/KBI3/PGD
Legend:
Pin
Type
P2SSAC<1:0>
DC2B<1:0>
CCP3AS<2:0>
P3M<1:0>
GIE/GIEH PEIE/GIEL
INTCON2
RBPU
INTEDG0
P2SSBD<1:0>
CCP2M<3:0>
P3SSAC<1:0>
DC3B<1:0>
205
201
P3SSBD<1:0>
CCP3M<3:0>
205
201
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
INTEDG1
INTEDG2
—
TMR0IP
—
RBIP
116
INTCON3
INT2IP
INT1IP
—
INT2IE
INT1IE
—
INT2IF
INT1IF
117
IOCB
IOCB7
IOCB6
IOCB5
IOCB4
—
—
—
—
156
LATB
LATB7
LATB6
LATB5
LATB4
LATB3
LATB2
LATB1
LATB0
155
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
151
SLRCON
—
—
—
SLRE(1)
SLRD(1)
SLRC
SLRB
SLRA
T1GCON
TMR1GE
T1GPOL
T1GTM
T1GSPM
T1GGO/DONE
T1GVAL
PORTB
T3SOSCEN
T3SYNC
T5GPOL
T5GTM
T5GSPM
T5GGO_DONE
T5GVAL
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
WPUB
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
155
T5GCON
Legend:
Note 1:
TMR3CS<1:0>
T3RD16
TMR3ON
156
171
TMR5GE
T3CON
T3CKPS<1:0>
T1GSS<1:0>
T5GSS
170
171
— = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTB.
Available on PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 141
PIC18(L)F2X/4XK22
TABLE 10-7:
Name
CONFIGURATION REGISTERS ASSOCIATED WITH PORTB
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
CONFIG4L
DEBUG
XINST
—
—
—
LVP(1)
—
STRVEN
355
Legend:
Note 1:
10.4
— = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTB.
Can only be changed when in high voltage programming mode.
PORTC Registers
EXAMPLE 10-3:
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., disable the output driver). Clearing a
TRISC bit (= 0) will make the corresponding PORTC
pin an output (i.e., enable the output driver and 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 10-8). The pins have Schmitt Trigger input buffers.
Some of these pin functions can be relocated to alternate pins using the Control fuse bits in CONFIG3H.
RC0 is the default pin for T3CKI. Clearing the T3CMX
bit moves the pin function to RB5. RC1 is the default pin
for the CCP2 peripheral pin. Clearing the CCP2MX bit
moves the pin function to the RB3 pin.
Two other pin functions, P2B and CCP3, can be relocated from their default pins to PORTC pins by clearing
the control fuses in CONFIG3H. Clearing P2BMX and
CCP3MX moves the pin functions to RC0 and RC6(1)/
RE0(2), respectively.
When enabling peripheral functions, care should be
taken in defining TRIS bits for each PORTC pin. The
EUSART and MSSP peripherals override the TRIS bit
to make a pin an output or an input, depending on the
peripheral configuration. Refer to the corresponding
peripheral section for additional information.
Note:
On a Power-on Reset, these pins are configured as analog inputs.
MOVLB
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
10.4.1
0xF
PORTC
;
;
;
;
LATC
;
;
;
0CFh
;
;
;
TRISC
;
;
;
30h
;
;
ANSELC ;
;
;
INITIALIZING PORTC
Set BSR for banked SFRs
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
Value used to
enable digital inputs
RC<3:2> dig input enable
No ANSEL bits for RC<1:0>
RC<7:6> dig input enable
PORTC OUTPUT PRIORITY
Each PORTC pin is multiplexed with other functions.
The pins, their combined functions and their output
priorities are briefly described here. For additional
information, refer to the appropriate section in this data
sheet.
When multiple outputs are enabled, the actual pin
control goes to the peripheral with the higher priority.
Table 10-4 lists the PORTC pin functions from the
highest to the lowest priority.
Analog input functions, such as ADC, comparator and
SR Latch inputs, are not shown in the priority lists.
These inputs are active when the I/O pin is set for
Analog mode using the ANSELx registers. Digital
output functions may control the pin when it is in Analog
mode with the priority shown below.
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.
DS41412C-page 142
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-8:
PORTC I/O SUMMARY
Pin Name
RC0/P2B/T3CKI/T3G/
T1CKI/SOSCO
RC1/P2A/CCP2/SOSCI
RC2/CTPLS/P1A/
CCP1/T5CKI/AN14
Function
TRIS
Setting
ANSEL
setting
Pin
Type
Buffer
Type
Description
RC0
0
1
O
DIG
LATC<0> data output; not affected by analog input.
1
0
I
ST
PORTC<0> data input; disabled when analog input
enabled.
P2B(2)
0
1
O
DIG
Enhanced CCP2 PWM output 2.
T3CKI(1)
1
0
I
ST
Timer3 clock input.
Timer3 external clock gate input.
T3G
1
0
I
ST
T1CKI
1
0
I
ST
SOSCO
x
—
O
XTAL
RC1
0
1
O
DIG
LATC<1> data output; not affected by analog input.
1
0
I
ST
PORTC<1> data input; disabled when analog input
enabled.
P2A
0
1
O
DIG
Enhanced CCP2 PWM output 1.
CCP2(1)
0
1
O
DIG
Compare 2 output/PWM 2 output.
1
0
I
ST
SOSCI
x
—
I
XTAL
RC2
0
1
O
DIG
LATC<2> data output; not affected by analog input.
1
0
I
ST
PORTC<2> data input; disabled when analog input
enabled.
0
1
O
DIG
CTMU pulse generator output.
CTPLS
RC3/SCK1/SCL1/AN15
P1A
0
1
O
DIG
Enhanced CCP1 PWM output 1.
0
1
O
DIG
Compare 1 output/PWM 1 output.
1
0
I
ST
Capture 1 input.
T5CKI
1
0
I
ST
Timer5 clock input.
AN14
1
1
I
AN
Analog input 14.
RC3
0
1
O
DIG
LATC<3> data output; not affected by analog input.
1
0
I
ST
PORTC<3> data input; disabled when analog input
enabled.
0
1
O
DIG
MSSP1 SPI Clock output.
1
0
I
ST
MSSP1 SPI Clock input.
0
1
O
DIG
MSSP1 I2C™ Clock output.
1
0
I
I2C
MSSP1 I2C™ Clock input.
AN15
1
1
I
AN
Analog input 15.
RC4
0
1
O
DIG
LATC<4> data output; not affected by analog input.
1
0
I
ST
PORTC<4> data input; disabled when analog input
enabled.
SCL1
SDI1
1
0
I
ST
MSSP1 SPI data input.
SDA1
0
0
O
DIG
MSSP1 I2C™ data output.
1
0
I
I2C
MSSP1 I2C™ data input.
1
1
I
AN
Analog input 16.
AN16
Legend:
Note 1:
2:
3:
Capture 2 input.
Secondary oscillator input.
CCP1
SCK1
RC4/SDI1/SDA1/AN16
Timer1 clock input.
Secondary oscillator output.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS =
CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Function on PORTD and PORTE for PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 143
PIC18(L)F2X/4XK22
TABLE 10-8:
PORTC I/O SUMMARY (CONTINUED)
Pin Name
RC5/SDO1/AN17
Function
TRIS
Setting
ANSEL
setting
Pin
Type
Buffer
Type
Description
RC5
0
1
O
DIG
LATC<5> data output; not affected by analog input.
1
0
I
ST
PORTC<5> data input; disabled when analog input
enabled.
0
1
O
DIG
MSSP1 SPI data output.
I
AN
Analog input 17.
0
1
O
DIG
LATC<6> data output; not affected by analog input.
1
0
I
ST
PORTC<6> data input; disabled when analog input
enabled.
P3A(2), (3)
0
1
O
CCP3(2), (3)
0
1
O
DIG
Compare 3 output/PWM 3 output.
1
0
I
ST
Capture 3 input.
SDO1
AN17
RC6/P3A/CCP3/TX1/
CK1/AN18
RC7/P3B/RX1/DT1/
AN19
RC6
TX1
0
1
O
DIG
EUSART 1 asynchronous transmit data output.
CK1
0
1
O
DIG
EUSART 1 synchronous serial clock output.
1
0
I
ST
EUSART 1 synchronous serial clock input.
AN18
1
1
I
AN
Analog input 18.
RC7
0
1
O
DIG
LATC<7> data output; not affected by analog input.
1
0
I
ST
PORTC<7> data input; disabled when analog input
enabled.
P3B
0
1
O
RX1
1
0
I
ST
EUSART 1 asynchronous receive data in.
DT1
0
1
O
DIG
EUSART 1 synchronous serial data output.
1
0
I
ST
EUSART 1 synchronous serial data input.
1
1
I
AN
Analog input 19.
AN19
Legend:
Note 1:
2:
3:
CMOS Enhanced CCP3 PWM output 1.
CMOS Enhanced CCP3 PWM output 2.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS =
CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Alternate pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are clear.
Function on PORTD and PORTE for PIC18(L)F4XK22 devices.
DS41412C-page 144
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-9:
Name
ANSELC
ECCP1AS
Bit 7
Bit 6
ANSC7
ANSC6
CCP1ASE
CCP1CON
P1M<1:0>
CCP2CON
Bit 4
Bit 3
Bit 2
ANSC5
ANSC4
ANSC3
ANSC2
P1SSAC<1:0>
DC1B<1:0>
Bit 1
Bit 0
Register
on Page
—
—
153
P1SSBD<1:0>
CCP1M<3:0>
CCP2AS<2:0>
P2M<1:0>
CTMUCONH
Bit 5
CCP1AS<2:0>
CCP2ASE
ECCP2AS
LATC
REGISTERS ASSOCIATED WITH PORTC
201
P2SSAC<1:0>
DC2B<1:0>
205
P2SSBD<1:0>
CCP2M<3:0>
205
201
CTMUEN
—
CTMUSIDL
TGEN
EDGEN
EDGSEQEN
IDISSEN
CTTRIG
329
LATC7
LATC6
LATC5
LATC4
LATC3
LATC2
LATC1
LATC0
155
PORTC
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
151
RCSTA1
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
SLRCON
—
—
—
SLRE(1)
SLRD(1)
SLRC
SLRB
SLRA
156
WCOL
SSPOV
SSPEN
CKP
T1CKPS<1:0>
T1SOSCEN
T1SYNC
T1RD16
TMR1ON
170
T3CKPS<1:0>
T3SOSCEN
T3SYNC
T3RD16
TMR3ON
170
SSP1CON1
T1CON
T3CON
T3GCON
T5CON
TRISC
TXSTA1
Legend:
Note 1:
TMR1CS<1:0>
TMR3CS<1:0>
TMR3GE
T3GPOL
T3GTM
SSPM<3:0>
T3GSPM T3GGO/DONE
T3GVAL
T3GSS
171
T5OSCEN
T5SYNC
T5RD16
TMR5ON
170
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TMR5CS<1:0>
T5CKPS<1:0>
256
— = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTC.
Available on PIC18(L)F4XK22 devices.
TABLE 10-10: CONFIGURATION REGISTERS ASSOCIATED WITH PORTC
Name
CONFIG3H
Legend:
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
— = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTC.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 145
PIC18(L)F2X/4XK22
10.5
Note:
PORTD Registers
10.5.1
PORTD is only available on 40-pin and 44pin 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., disable the output driver). Clearing a
TRISD bit (= 0) will make the corresponding PORTD
pin an output (i.e., enable the output driver and 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.
PORTD OUTPUT PRIORITY
Each PORTD pin is multiplexed with other functions.
The pins, their combined functions and their output
priorities are briefly described here. For additional
information, refer to the appropriate section in this data
sheet.
When multiple outputs are enabled, the actual pin
control goes to the peripheral with the higher priority.
Table 10-4 lists the PORTD pin functions from the
highest to the lowest priority.
Analog input functions, such as ADC, comparator and
SR Latch inputs, are not shown in the priority lists.
These inputs are active when the I/O pin is set for
Analog mode using the ANSELx registers. Digital
output functions may control the pin when it is in Analog
mode with the priority shown below.
All of the PORTD pins are multiplexed with analog and
digital peripheral modules. See Table .
Note:
On a Power-on Reset, these pins are
configured as analog inputs.
EXAMPLE 10-4:
MOVLB
CLRF
CLRF
MOVLW
MOVWF
MOVLW
MOVWF
0xF
PORTD
;
;
;
;
LATD
;
;
;
0CFh
;
;
;
TRISD
;
;
;
30h
;
;
ANSELD ;
;
DS41412C-page 146
INITIALIZING PORTD
Set BSR for banked SFRs
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
Value used to
enable digital inputs
RD<3:0> dig input enable
RC<7:6> dig input enable
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-11: PORTD I/O SUMMARY
Pin Name
Function
RD0/SCK2/SCL2/AN20
RD0
1
O
DIG
LATD<0> data output; not affected by analog input.
1
0
I
ST
PORTD<0> data input; disabled when analog input
enabled.
0
1
O
DIG
MSSP2 SPI Clock output.
1
0
I
ST
MSSP2 SPI Clock input.
0
1
O
DIG
MSSP2 I2C™ Clock output.
1
0
I
I2C
MSSP2 I2C™ Clock input.
AN20
1
1
I
AN
Analog input 20.
RD1
0
1
O
DIG
LATD<1> data output; not affected by analog input.
1
0
I
ST
PORTD<1> data input; disabled when analog input
enabled.
0
1
O
DIG
Compare 4 output/PWM 4 output.
1
0
I
ST
Capture 4 input.
SDI2
1
0
I
ST
MSSP2 SPI data input.
SDA2
0
0
O
DIG
MSSP2 I2C™ data output.
1
0
I
I2C
MSSP2 I2C™ data input.
AN21
1
1
I
AN
Analog input 21.
RD2
0
1
O
DIG
LATD<2> data output; not affected by analog input.
1
0
I
ST
PORTD<2> data input; disabled when analog input
enabled.
0
1
O
DIG
Enhanced CCP2 PWM output 2.
SCL2
CCP4
RD2/P2B/AN22
P2B(1)
RD3/P2C/SS2/AN23
RD4/P2D/SDO2/AN24
RD5/P1B/AN25
AN22
1
1
I
AN
Analog input 22.
RD3
0
1
O
DIG
LATD<3> data output; not affected by analog input.
1
0
I
ST
PORTD<3> data input; disabled when analog input
enabled.
P2C
0
1
O
DIG
Enhanced CCP2 PWM output 4.
SS2
1
0
I
TTL
MSSP2 SPI slave select input.
AN23
1
1
I
AN
Analog input 23.
RD4
0
1
O
DIG
LATD<4> data output; not affected by analog input.
1
0
I
ST
PORTD<4> data input; disabled when analog input
enabled.
P2D
0
1
O
DIG
Enhanced CCP2 PWM output 3.
SDO2
0
1
O
DIG
MSSP2 SPI data output.
AN24
1
1
I
AN
Analog input 24.
RD5
0
1
O
DIG
LATD<5> data output; not affected by analog input.
1
0
I
ST
PORTD<5> data input; disabled when analog input
enabled.
0
1
O
DIG
Enhanced CCP1 PWM output 2.
I
AN
Analog input 25.
P1B
AN25
Legend:
Note 1:
Description
0
SCK2
RD1/CCP4/SDI2/SDA2/
AN21
TRIS ANSEL Pin Buffer
Setting setting Type Type
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS
= CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 147
PIC18(L)F2X/4XK22
TABLE 10-11: PORTD I/O SUMMARY
Pin Name
Function
RD6/P1C/TX2/CK2/
AN26
TRIS ANSEL Pin Buffer
Setting setting Type Type
RD6
0
1
O
DIG
LATD<6> data output; not affected by analog input.
1
0
I
ST
PORTD<6> data input; disabled when analog input
enabled.
P1C
0
1
O
DIG
Enhanced CCP1 PWM output 3.
TX2
0
1
O
DIG
EUSART 2 asynchronous transmit data output.
CK2
0
1
O
DIG
EUSART 2 synchronous serial clock output.
1
0
I
ST
EUSART 2 synchronous serial clock input.
AN26
1
1
I
AN
Analog input 26.
RD7
0
1
O
DIG
LATD<7> data output; not affected by analog input.
1
0
I
ST
PORTD<7> data input; disabled when analog input
enabled.
P1D
0
1
O
DIG
Enhanced CCP1 PWM output 4.
RX2
1
0
I
ST
EUSART 2 asynchronous receive data in.
DT2
0
1
O
DIG
EUSART 2 synchronous serial data output.
1
0
I
ST
EUSART 2 synchronous serial data input.
1
1
I
AN
Analog input 27.
RD7/P1D/RX2/DT2/
AN27
AN27
Legend:
Description
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS
= CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Default pin assignment for P2B, T3CKI, CCP3 and CCP2 when Configuration bits PB2MX, T3CMX, CCP3MX and
CCP2MX are set.
Note 1:
TABLE 10-12: REGISTERS ASSOCIATED WITH PORTD
Name
Bit 7
Bit 6
ANSELD(1)
ANSD7
BAUDCON2
ABDOVF
Bit 0
Register on
Page
ANSD1
ANSD0
153
WUE
ABDEN
274
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
ANSD6
ANSD5
ANSD4
ANSD3
ANSD2
RCIDL
DTRXP
CKTXP
BRG16
—
CCP1CON
P1M<1:0>
DC1B<1:0>
CCP1M<3:0>
201
CCP2CON
P2M<1:0>
DC2B<1:0>
CCP2M<3:0>
201
CCP4CON
DC4B<1:0>
CCP4M<3:0>
—
—
LATD7
LATD6
PORTD(1)
RD7
RD6
RD5
RD4
RD3
RD2
RCSTA2
SPEN
RX9
SREN
CREN
ADDEN
FERR
SLRD
SLRC
SLRB
LATD(1)
(1)
LATD5
LATD4
—
—
—
SLRE
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
TRISD(1)
TRISD7
TRISD6 TRISD5
SLRCON
TRISD4
LATD3
LATD2
LATD1
201
LATD0
155
RD1
RD0
151
OERR
RX9D
273
SLRA
156
SSPM<3:0>
TRISD3
TRISD2
TRISD1
256
TRISD0
154
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTD.
Note 1: Available on PIC18(L)F4XK22 devices.
TABLE 10-13: CONFIGURATION REGISTERS ASSOCIATED WITH PORTD
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
Bit 2
Bit 1
Bit 0
CCP3MX PBADEN CCP2MX
Register
on Page
354
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTD.
DS41412C-page 148
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
10.6
PORTE Registers
10.6.2
Depending on the particular PIC18(L)F2X/4XK22
device selected, PORTE is implemented in two
different ways.
10.6.1
PORTE ON 40/44-PIN DEVICES
For PIC18(L)F2X/4XK22 devices, PORTE is a 4-bit
wide port. Three pins (RE0/P3A/CCP3/AN5, RE1/P3B/
AN6 and RE2/CCP5/AN7) are individually configurable
as inputs or outputs. These pins have Schmitt Trigger
input buffers. When selected as an analog input, 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., disable the output driver).
Clearing a TRISE bit (= 0) will make the corresponding
PORTE pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
TRISE controls the direction of the REx 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.
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.
Note:
On a Power-on Reset, RE<2:0> are
configured as analog inputs.
The fourth pin of PORTE (MCLR/VPP/RE3) is an input
only pin. Its operation is controlled by the MCLRE
Configuration bit. When selected as a port pin
(MCLRE = 0), it functions as a digital input only pin; as
such, it does not have TRIS or LAT bits associated with its
operation. Otherwise, it functions as the device’s Master
Clear input. In either configuration, RE3 also functions as
the programming voltage input during programming.
Note:
On a Power-on Reset, RE3 is enabled as
a digital input only if Master Clear
functionality is disabled.
EXAMPLE 10-5:
CLRF
CLRF
CLRF
MOVLW
MOVWF
PORTE
;
;
;
LATE
;
;
;
ANSELE ;
;
05h
;
;
;
TRISE
;
;
;
PORTE ON 28-PIN DEVICES
For PIC18F2XK22 devices, PORTE is only available
when Master Clear functionality is disabled
(MCLR = 0). In these cases, PORTE is a single bit,
input only port comprised of RE3 only. The pin operates
as previously described.
10.6.3
RE3 WEAK PULL-UP
The port RE3 pin has an individually controlled weak
internal pull-up. When set, the WPUE3 (TRISE<7>) bit
enables the RE3 pin pull-up. The RBPU bit of the
INTCON2 register controls pull-ups on both PORTB
and PORTE. When RBPU = 0, the weak pull-ups
become active on all pins which have the WPUE3 or
WPUBx bits set. When set, the RBPU bit disables all
weak pull-ups. The pull-ups are disabled on a Poweron Reset. When the RE3 port pin is configured as
(CONFIG3H<7>,
MCLRE=1
and
MCLR,
CONFIG4L<2>, LVP=0), or configured for Low Voltage
Programming, (MCLRE=x and LVP=1), the pull-up is
always enabled and the WPUE3 bit has no effect.
10.6.4
PORTE OUTPUT PRIORITY
Each PORTE pin is multiplexed with other functions.
The pins, their combined functions and their output
priorities are briefly described here. For additional
information, refer to the appropriate section in this data
sheet.
When multiple outputs are enabled, the actual pin
control goes to the peripheral with the higher priority.
Table 10-4 lists the PORTE pin functions from the
highest to the lowest priority.
Analog input functions, such as ADC, comparator and
SR Latch inputs, are not shown in the priority lists.
These inputs are active when the I/O pin is set for
Analog mode using the ANSELx registers. Digital
output functions may control the pin when it is in Analog
mode with the priority shown below.
INITIALIZING PORTE
Initialize PORTE by
clearing output
data latches
Alternate method
to clear output
data latches
Configure analog pins
for digital only
Value used to
initialize data
direction
Set RE<0> as input
RE<1> as output
RE<2> as input
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 149
PIC18(L)F2X/4XK22
TABLE 10-14: PORTE I/O SUMMARY
Pin
Function
RE0/P3A/CCP3/AN5
RE0
TRIS ANSEL Pin
Setting Setting Type
1
O
DIG
LATE<0> data output; not affected by analog input.
1
0
I
ST
PORTE<0> data input; disabled when analog input
enabled.
P3A(1)
0
1
O
DIG
Enhanced CCP3 PWM output.
CCP3(1)
0
1
O
DIG
Compare 3 output/PWM 3 output.
RE2/CCP5/AN7
1
0
I
ST
Capture 3 input.
AN5
1
1
I
AN
Analog input 5.
RE1
0
1
O
DIG
LATE<1> data output; not affected by analog input.
1
0
I
ST
PORTE<1> data input; disabled when analog input
enabled.
P3B
0
x
O
DIG
Enhanced CCP3 PWM output.
AN6
1
1
I
AN
Analog input 6.
RE2
0
1
O
DIG
LATE<2> data output; not affected by analog input.
1
0
I
ST
PORTE<2> data input; disabled when analog input
enabled.
0
1
O
DIG
Compare 5 output/PWM 5 output.
1
0
I
ST
Capture 5 input.
CCP5
RE3/VPP/MCLR
Note 1:
Description
0
RE1/P3B/AN6
Legend:
Buffer
Type
AN7
1
1
I
AN
Analog input 7.
RE3
—
—
I
ST
PORTE<3> data input; enabled when Configuration bit
MCLRE = 0.
VPP
—
—
P
AN
Programming voltage input; always available
MCLR
—
—
I
ST
Active-low Master Clear (device Reset) input; enabled
when configuration bit MCLRE = 1.
AN = Analog input or output; TTL = TTL compatible input; HV = High Voltage; OD = Open Drain; XTAL = Crystal; CMOS
= CMOS compatible input or output; ST = Schmitt Trigger input with CMOS levels; I2CTM = Schmitt Trigger input with I2C.
Alternate pin assignment for P3A/CCP3 when Configuration bit CCP3MX is clear..
TABLE 10-15: REGISTERS ASSOCIATED WITH PORTE
Name
Bit 7
ANSELE(1)
—
INTCON2
RBPU
Bit 6
Bit 5
—
—
INTEDG0 INTEDG1
Bit 2
Bit 1
Bit 0
Reset
Values
on page
—
ANSE2
ANSE1
ANSE0
154
—
TMR0IP
—
RBIP
116
Bit 4
Bit 3
—
INTEDG2
(1)
LATE
—
—
—
—
—
LATE2
LATE1
LATE0
155
PORTE
—
—
—
—
RE3
RE2(1)
RE1(1)
RE0(1)
152
SLRCON
—
—
—
SLRE(1)
SLRD(1)
SLRC
SLRB
SLRA
156
—
TRISE2(1)
TRISE1(1)
TRISE0(1)
154
TRISE
WPUE3
—
—
—
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for PORTE.
Note 1: Available on PIC18(L)F4XK22 devices.
DS41412C-page 150
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 10-16: CONFIGURATION REGISTERS ASSOCIATED WITH PORTE
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CONFIG4L
DEBUG
XINST
—
—
—
Bit 2
Bit 1
Bit 0
CCP3MX PBADEN CCP2MX
(1)
LVP
—
STRVEN
Reset
Values
on page
354
355
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for Interrupts.
Note 1: Can only be changed when in high voltage programming mode.
10.7
Port Analog Control
10.8
Most port pins are multiplexed with analog functions
such as the Analog-to-Digital Converter and
comparators. When these I/O pins are to be used as
analog inputs it is necessary to disable the digital input
buffer to avoid excessive current caused by improper
biasing of the digital input. Individual control of the
digital input buffers on pins which share analog
functions is provided by the ANSELA, ANSELB,
ANSELC, ANSELD and ANSELE registers. Setting an
ANSx bit high will disable the associated digital input
buffer and cause all reads of that pin to return ‘0’ while
allowing analog functions of that pin to operate
correctly.
Port Slew Rate Control
The output slew rate of each port is programmable to
select either the standard transition rate or a reduced
transition rate of approximately 0.1 times the standard
to minimize EMI. The reduced transition time is the
default slew rate for all ports.
The state of the ANSx bits has no affect on digital
output functions. A pin with the associated TRISx bit
clear and ANSx bit set will still operate as a digital
output but the input mode will be analog. This can
cause unexpected behavior when performing readmodify-write operations on the affected port.
All ANSEL register bits default to ‘1’ upon POR and
BOR, disabling digital inputs for their associated port
pins. All TRIS register bits default to ‘1’ upon POR or
BOR, disabling digital outputs for their associated port
pins. As a result, all port pins that have an ANSEL
register will default to analog inputs upon POR or BOR.
REGISTER 10-1:
PORTX(1): PORTx REGISTER
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
Rx7
Rx6
Rx5
Rx4
Rx3
Rx2
Rx1
Rx0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
bit 7-0
Note 1:
2:
Rx<7:0>: PORTx I/O bit values(2)
Register Description for PORTA, PORTB, PORTC and PORTD.
Writes to PORTx are written to corresponding LATx register. Reads from PORTx register is return of I/O
pin values.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 151
PIC18(L)F2X/4XK22
REGISTER 10-2:
PORTE: PORTE REGISTER
U-0
U-0
U-0
U-0
R/W-u/x
R/W-u/x
R/W-u/x
R/W-u/x
—
—
—
—
RE3(1)
RE2(2), (3)
RE1(2), (3)
RE0(2), (3)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
bit 7-4
Unimplemented: Read as ‘0’
bit 3
RE3: PORTE Input bit value(1)
bit 2-0
RE<2:0>: PORTE I/O bit values(2), (3)
Note 1:
2:
3:
Port is available as input only when MCLRE = 0.
Writes to PORTx are written to corresponding LATx register. Reads from PORTx register is return of I/O
pin values.
Available on PIC18(L)F4XK22 devices.
REGISTER 10-3:
ANSELA – PORTA ANALOG SELECT REGISTER
U-0
U-0
R/W-1
U-0
R/W-1
R/W-1
R/W-1
R/W-1
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
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 7-6
Unimplemented: Read as ‘0’
bit 5
ANSA5: RA5 Analog Select bit
1 = Digital input buffer disabled
0 = Digital input buffer enabled
bit 4
Unimplemented: Read as ‘0’
bit 3-0
ANSA<3:0>: RA<3:0> Analog Select bit
1 = Digital input buffer disabled
0 = Digital input buffer enabled
DS41412C-page 152
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 10-4:
ANSELB – PORTB ANALOG SELECT REGISTER
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
ANSB0
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 7-6
Unimplemented: Read as ‘0’
bit 5-0
ANSB<5:0>: RB<5:0> Analog Select bit
1 = Digital input buffer disabled
0 = Digital input buffer enabled
REGISTER 10-5:
x = Bit is unknown
ANSELC – PORTC ANALOG SELECT REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
U-0
U-0
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
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 7-2
ANSC<7:2>: RC<7:2> Analog Select bit
1 = Digital input buffer disabled
0 = Digital input buffer enabled
bit 1-0
Unimplemented: Read as ‘0’
REGISTER 10-6:
x = Bit is unknown
ANSELD – PORTD ANALOG SELECT 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
ANSD7
ANSD6
ANSD5
ANSD4
ANSD3
ANSD2
ANSD1
ANSD0
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 7-0
x = Bit is unknown
ANSD<7:0>: RD<7:0> Analog Select bit
1 = Digital input buffer disabled
0 = Digital input buffer enabled
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 153
PIC18(L)F2X/4XK22
REGISTER 10-7:
ANSELE – PORTE ANALOG SELECT REGISTER
U-0
U-0
U-0
U-0
U-0
R/W-1
R/W-1
R/W-1
—
—
—
—
—
ANSE2(1)
ANSE1(1)
ANSE0(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 7-3
Unimplemented: Read as ‘0’
bit 2-0
ANSE<2:0>: RE<2:0> Analog Select bit(1)
1 = Digital input buffer disabled
0 = Digital input buffer enabled
Note 1:
x = Bit is unknown
Available on PIC18(L)F4XK22 devices only.
REGISTER 10-8:
TRISx: PORTx TRI-STATE 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
TRISx7
TRISx6
TRISx5
TRISx4
TRISx3
TRISx2
TRISx1
TRISx0
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 7-0
Note 1:
x = Bit is unknown
TRISx<7:0>: PORTx Tri-State Control bit
1 = PORTx pin configured as an input (tri-stated)
0 = PORTx pin configured as an output
Register description for TRISA, TRISB, TRISC and TRISD.
REGISTER 10-9:
R/W-1
TRISE: PORTE TRI-STATE REGISTER
U-0
WPUE3
—
U-0
—
U-0
—
U-0
—
R/W-1
TRISE2
(1)
R/W-1
(1)
TRISE1
R/W-1
TRISE0(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
WPUE3: Weak Pull-up Register bits
1 = Pull-up enabled on PORT pin
0 = Pull-up disabled on PORT pin
bit 6-3
Unimplemented: Read as ‘0’
bit 2-0
TRISE<7:0>: PORTE Tri-State Control bit(1)
1 = PORTE pin configured as an input (tri-stated)
0 = PORTE pin configured as an output
Note 1:
x = Bit is unknown
Available on PIC18(L)F4XK22 devices only.
DS41412C-page 154
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 10-10: LATx: PORTx OUTPUT LATCH REGISTER(1)
R/W-x/u
R/W-x/u
R/W-x/u
R/W-x/u
R/W-x/u
R/W-x/u
R/W-x/u
R/W-x/u
LATx7
LATx6
LATx5
LATx4
LATx3
LATx2
LATx1
LATx0
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
LATx<7:0>: PORTx Output Latch bit value(2)
bit 7-0
Note 1:
2:
x = Bit is unknown
Register Description for LATA, LATB, LATC and LATD.
Writes to PORTA are written to corresponding LATA register. Reads from PORTA register is return of I/O
pin values.
REGISTER 10-11: LATE: PORTE OUTPUT LATCH REGISTER(1)
U-0
U-0
U-0
U-0
U-0
R/W-x/u
R/W-x/u
R/W-x/u
—
—
—
—
—
LATE2
LATE1
LATE0
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 7-3
Unimplemented: Read as ‘0’
bit 2-0
LATE<2:0>: PORTE Output Latch bit value(2)
Note 1:
2:
x = Bit is unknown
Available on PIC18(L)F4XK22 devices only.
Writes to PORTA are written to corresponding LATA register. Reads from PORTA register is return of I/O
pin values.
REGISTER 10-12: WPUB: WEAK PULL-UP PORTB 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
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
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 7-0
x = Bit is unknown
WPUB<7:0>: Weak Pull-up Register bits
1 = Pull-up enabled on PORT pin
0 = Pull-up disabled on PORT pin
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 155
PIC18(L)F2X/4XK22
REGISTER 10-13: IOCB: INTERRUPT-ON-CHANGE PORTB CONTROL REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
U-0
U-0
U-0
U-0
IOCB7
IOCB6
IOCB5
IOCB4
—
—
—
—
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 7-4
Note 1:
x = Bit is unknown
IOCB<7:4>: Interrupt-on-Change PORTB control bits
1 = Interrupt-on-change enabled(1)
0 = Interrupt-on-change disabled
Interrupt-on-change requires that the RBIE bit (INTCON<3>) is set.
REGISTER 10-14: SLRCON: SLEW RATE CONTROL REGISTER
U-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
—
—
—
SLRE(1)
SLRD(1)
SLRC
SLRB
SLRA
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 7-5
Unimplemented: Read as ‘0’
bit 4
SLRE: PORTE Slew Rate Control bit(1)
1 = All outputs on PORTE slew at a limited rate
0 = All outputs on PORTE slew at the standard rate
bit 3
SLRD: PORTD Slew Rate Control bit(1)
1 = All outputs on PORTD slew at a limited rate
0 = All outputs on PORTD slew at the standard rate
bit 2
SLRC: PORTC Slew Rate Control bit
1 = All outputs on PORTC slew at a limited rate
0 = All outputs on PORTC slew at the standard rate
bit 1
SLRB: PORTB Slew Rate Control bit
1 = All outputs on PORTB slew at a limited rate
0 = All outputs on PORTB slew at the standard rate
bit 0
SLRA: PORTA Slew Rate Control bit
1 = All outputs on PORTA slew at a limited rate(2)
0 = All outputs on PORTA slew at the standard rate
Note 1:
2:
x = Bit is unknown
These bits are available on PIC18(L)F4XK22 devices.
The slew rate of RA6 defaults to standard rate when the pin is used as CLKOUT.
DS41412C-page 156
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
11.0
TIMER0 MODULE
The T0CON register (Register 11-1) controls all
aspects of the module’s operation, including the
prescale selection. It is both readable and writable.
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:
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
TMR0ON
T08BIT
T0CS
T0SE
PSA
R/W-1
R/W-1
R/W-1
TOPS<2:0>
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 (CLKOUT)
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
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 157
PIC18(L)F2X/4XK22
11.1
Timer0 Operation
11.2
Timer0 can operate as either a timer or a counter; the
mode is selected with the T0CS bit of the T0CON
register. 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”). Timer0 incrementing is inhibited for two
instruction cycles following a TMR0 register write. The
user can work around this by adjusting the value written
to the TMR0 register to compensate for the anticipated
missing increments.
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 RA4/T0CKI. The incrementing edge is determined by the Timer0 Source Edge
Select bit, T0SE of the T0CON register; clearing this bit
selects the rising edge. Restrictions on the external
clock input are discussed below.
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 neither 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 the need to verify that the read of the
high and low byte were valid. Invalid reads could
otherwise occur 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. Writing
to TMR0H does not directly affect Timer0. Instead, the
high byte of Timer0 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.
An external clock source can be used to drive Timer0;
however, it must meet certain requirements (see
Table 27-11) to ensure that the external clock can be
synchronized with the internal phase clock (TOSC).
There is a delay between synchronization and the
onset of incrementing the timer/counter.
FIGURE 11-1:
TIMER0 BLOCK DIAGRAM (8-BIT MODE)
FOSC/4
0
1
1
T0CKI pin
T0SE
T0CS
Programmable
Prescaler
0
Sync with
Internal
Clocks
Set
TMR0IF
on Overflow
(2 TCY Delay)
8
3
T0PS<2:0>
8
PSA
Note:
TMR0L
Internal Data Bus
Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
DS41412C-page 158
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 11-2:
TIMER0 BLOCK DIAGRAM (16-BIT MODE)
FOSC/4
0
1
Sync with
Internal
Clocks
1
Programmable
Prescaler
T0CKI pin
T0SE
T0CS
0
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:
11.3
Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
Prescaler
11.3.1
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 of the
T0CON register which determine the prescaler
assignment and prescale ratio.
Clearing the PSA bit assigns the prescaler to the
Timer0 module. When the prescaler is assigned,
prescale values from 1:2 through 1:256 in integer
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
INTCON
INTCON2
T0CON
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 of the INTCON register. Before
re-enabling the interrupt, the TMR0IF bit must be
cleared by software in 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
GIE/GIEH PEIE/GIEL TMR0IE
RBPU
TMR0ON
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
—
TMR0IP
—
RBIP
INTEDG0 INTEDG1 INTEDG2
T08BIT
T0CS
T0SE
PSA
T0PS<2:0>
116
157
TMR0H
Timer0 Register, High Byte
—
TMR0L
Timer0 Register, Low Byte
—
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used by Timer0.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 159
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 160
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
12.0
TIMER1/3/5 MODULE WITH
GATE CONTROL
•
•
•
•
•
•
The Timer1/3/5 module is a 16-bit timer/counter with
the following features:
•
•
•
•
•
•
•
•
16-bit timer/counter register pair (TMRxH:TMRxL)
Programmable internal or external clock source
2-bit prescaler
Dedicated Secondary 32 kHz oscillator circuit
Optionally synchronized comparator out
Multiple Timer1/3/5 gate (count enable) sources
Interrupt on overflow
Wake-up on overflow (external clock,
Asynchronous mode only)
• 16-Bit Read/Write Operation
• Time base for the Capture/Compare function
FIGURE 12-1:
Special Event Trigger (with CCP/ECCP)
Selectable Gate Source Polarity
Gate Toggle Mode
Gate Single-pulse Mode
Gate Value Status
Gate Event Interrupt
Figure 12-1 is a block diagram of the Timer1/3/5
module.
TIMER1/3/5 BLOCK DIAGRAM
TxGSS<1:0>
TxGSPM
00
TxG
Timer2/4/6 Match
PR2/4/6
01
Comparator 1
SYNCC1OUT(7)
10
Comparator 2
SYNCC2OUT(7)
11
0
TxG_IN
Single Pulse
TMRxON
TxGVAL
0
D
Q
CK
R
Q
1
Acq. Control
1
Q1
Data Bus
D
Q
RD
TXGCON
EN
Interrupt
TxGGO/DONE
Set
TMRxGIF
det
TxGTM
TxGPOL
TMRxGE
Set flag bit
TMRxIF on
Overflow
TMRxON
To Comparator Module
TMRx(2),(4)
TMRxH
EN
TMRxL
Q
D
TxCLK
Synchronized
clock input
0
1
Secondary
Oscillator
Module
See Figure 2-4
TMRxCS<1:0>
Reserved
1
(5) ,(6)
TxSOSCEN
Note
TxCLK_EXT_SRC
(1)
0
TxCKI
TxSYNC
SOSCOUT
11
10
FOSC
Internal
Clock
01
FOSC/4
Internal
Clock
00
Synchronize(3),(7)
Prescaler
1, 2, 4, 8
det
2
TxCKPS<1:0>
FOSC/2
Internal
Clock
Sleep input
1:
2:
3:
4:
5:
6:
ST Buffer is high speed type when using TxCKI.
Timer1/3/5 register increments on rising edge.
Synchronize does not operate while in Sleep.
See Figure 12-2 for 16-Bit Read/Write Mode Block Diagram.
T1CKI is not available when the secondary oscillator is enabled. (SOSCGO = 1 or TXSOSCEN = 1)
T3CKI is not available when the secondary oscillator is enabled, unless T3CMX = 1.
7:
Synchronized comparator output should not be used in conjunction with synchronized TxCKI.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 161
PIC18(L)F2X/4XK22
12.1
Timer1/3/5 Operation
12.2.1
When the internal clock source is selected the
TMRxH:TMRxL register pair will increment on multiples
of FOSC as determined by the Timer1/3/5 prescaler.
The Timer1/3/5 module is a 16-bit incrementing
counter which is accessed through the TMRxH:TMRxL
register pair. Writes to TMRxH or TMRxL directly
update the counter.
When the FOSC internal clock source is selected, the
Timer1/3/5 register value will increment by four counts
every instruction clock cycle. Due to this condition, a
2 LSB error in resolution will occur when reading the
Timer1/3/5 value. To utilize the full resolution of
Timer1/3/5, an asynchronous input signal must be used
to gate the Timer1/3/5 clock input.
When used with an internal clock source, the module is
a timer and increments on every instruction cycle.
When used with an external clock source, the module
can be used as either a timer or counter and
increments on every selected edge of the external
source.
The following asynchronous sources may be used:
Timer1/3/5 is enabled by configuring the TMRxON and
TMRxGE bits in the TxCON and TxGCON registers,
respectively. Table 12-1 displays the Timer1/3/5 enable
selections.
TABLE 12-1:
12.2.2
0
0
Off
0
1
Off
1
0
Always On
1
1
Count Enabled
When enabled to count, Timer1/3/5 is incremented on
the rising edge of the external clock input of the TxCKI
pin. This external clock source can be synchronized to
the microcontroller system clock or it can run
asynchronously.
When used as a timer with a clock oscillator, an
external 32.768 kHz crystal can be used in conjunction
with the dedicated secondary internal oscillator circuit.
Clock Source Selection
Note:
The TMRxCS<1:0> and TxSOSCEN bits of the TxCON
register are used to select the clock source for
Timer1/3/5. The dedicated Secondary Oscillator circuit
can be used as the clock source for Timer1, Timer3 and
Timer5, simultaneously. Any of the TxSOSCEN bits will
enable the Secondary Oscillator circuit and select it as
the clock source for that particular timer. Table 12-2
displays the clock source selections.
TABLE 12-2:
EXTERNAL CLOCK SOURCE
When the external clock source is selected, the
Timer1/3/5 module may work as a timer or a counter.
Timer1/3/5
Operation
TMRxGE
12.2
• Asynchronous event on the TxG pin to Timer1/3/5
Gate
• C1 or C2 comparator input to Timer1/3/5 Gate
TIMER1/3/5 ENABLE
SELECTIONS
TMRxON
INTERNAL CLOCK SOURCE
In Counter mode, a falling edge must be
registered by the counter prior to the first
incrementing rising edge after any one or
more of the following conditions:
•
•
•
•
Timer1/3/5 enabled after POR
Write to TMRxH or TMRxL
Timer1/3/5 is disabled
Timer1/3/5 is disabled (TMRxON = 0)
when TxCKI is high then Timer1/3/5
is enabled (TMRxON=1) when TxCKI
is low.
CLOCK SOURCE SELECTIONS
TMRxCS1
TMRxCS0
TxSOSCEN
Clock Source
0
1
x
System Clock (FOSC)
0
0
x
Instruction Clock (FOSC/4)
1
0
0
External Clocking on TxCKI Pin
1
0
1
Osc.Circuit On SOSCI/SOSCO Pins
DS41412C-page 162
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
12.3
Timer1/3/5 Prescaler
12.5.1
Timer1/3/5 has four prescaler options allowing 1, 2, 4 or
8 divisions of the clock input. The TxCKPS bits of the
TxCON register control the prescale counter. The
prescale counter is not directly readable or writable;
however, the prescaler counter is cleared upon a write to
TMRxH or TMRxL.
12.4
Secondary Oscillator
A dedicated secondary low-power 32.768 kHz
oscillator circuit is built-in between pins SOSCI (input)
and SOSCO (amplifier output). This internal circuit is to
be used in conjunction with an external 32.768 kHz
crystal.
The oscillator circuit is enabled by setting the
TxSOSCEN bit of the TxCON register, the SOSCGO bit
of the OSCCON2 register or by selecting the
secondary oscillator as the system clock by setting
SCS<1:0> = 01 in the OSCCON register. The oscillator
will continue to run during Sleep.
Note:
12.5
The oscillator requires a start-up and
stabilization time before use. Thus,
TxSOSCEN should be set and a suitable
delay observed prior to enabling
Timer1/3/5.
Timer1/3/5 Operation in
Asynchronous Counter Mode
If control bit TxSYNC of the TxCON register is set, the
external clock input is not synchronized. The timer
increments asynchronously to the internal phase
clocks. If external clock source is selected then the
timer will continue to run during Sleep and can
generate an interrupt on overflow, which will wake-up
the processor. However, special precautions in
software are needed to read/write the timer (see
Section 12.5.1 “Reading and Writing Timer1/3/5 in
Asynchronous Counter Mode”).
Note:
When switching from synchronous to
asynchronous operation, it is possible to
skip an increment. When switching from
asynchronous to synchronous operation,
it is possible to produce an additional
increment.
READING AND WRITING
TIMER1/3/5 IN ASYNCHRONOUS
COUNTER MODE
Reading TMRxH or TMRxL while the timer is running
from an external asynchronous clock will ensure a valid
read (taken care of in hardware). However, the user
should keep in mind that reading the 16-bit timer in two
8-bit values itself, poses certain problems, since the
timer may overflow between the reads. For writes, it is
recommended that the user simply stop the timer and
write the desired values. A write contention may occur
by writing to the timer registers, while the register is
incrementing. This may produce an unpredictable
value in the TMRxH:TMRxL register pair.
12.6
Timer1/3/5 16-Bit Read/Write Mode
Timer1/3/5 can be configured to read and write all 16
bits of data, to and from, the 8-bit TMRxL and TMRxH
registers, simultaneously. The 16-bit read and write
operations are enabled by setting the RD16 bit of the
TxCON register.
To accomplish this function, the TMRxH register value
is mapped to a buffer register called the TMRxH buffer
register. While in 16-Bit mode, the TMRxH register is
not directly readable or writable and all read and write
operations take place through the use of this TMRxH
buffer register.
When a read from the TMRxL register is requested, the
value of the TMRxH register is simultaneously loaded
into the TMRxH buffer register. When a read from the
TMRxH register is requested, the value is provided
from the TMRxH buffer register instead. This provides
the user with the ability to accurately read all 16 bits of
the Timer1/3/5 value from a single instance in time.
In contrast, when not in 16-Bit mode, the user must
read each register separately and determine if the
values have become invalid due to a rollover that may
have occurred between the read operations.
When a write request of the TMRxL register is
requested, the TMRxH buffer register is simultaneously
updated with the contents of the TMRxH register. The
value of TMRxH must be preloaded into the TMRxH
buffer register prior to the write request for the TMRxL
register. This provides the user with the ability to write
all 16 bits to the TMRxL:TMRxH register pair at the
same time.
Any requests to write to the TMRxH directly does not
clear the Timer1/3/5 prescaler value. The prescaler
value is only cleared through write requests to the
TMRxL register.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 163
PIC18(L)F2X/4XK22
FIGURE 12-2:
TIMER1/3/5 16-BIT
READ/WRITE MODE
BLOCK DIAGRAM
12.7.2
The Timer1/3/5 Gate source can be selected from one
of four different sources. Source selection is controlled
by the TxGSS bits of the TxGCON register. The polarity
for each available source is also selectable. Polarity
selection is controlled by the TxGPOL bit of the
TxGCON register.
From
Timer1/3/5
Circuitry
TMR1
High Byte
TMR1L
8
Set
TMR1IF
on Overflow
TABLE 12-4:
Read TMR1L
TxGSS
Write TMR1L
8
8
TMR1H
8
8
Timer1/3/5 Gate
Timer1/3/5 can be configured to count freely or the
count can be enabled and disabled using Timer1/3/5
Gate circuitry. This is also referred to as Timer1/3/5
Gate Enable.
Timer1/3/5 Gate can also be driven by multiple
selectable sources.
12.7.1
TIMER1/3/5 GATE ENABLE
The Timer1/3/5 Gate Enable mode is enabled by
setting the TMRxGE bit of the TxGCON register. The
polarity of the Timer1/3/5 Gate Enable mode is
configured using the TxGPOL bit of the TxGCON
register.
When Timer1/3/5 Gate Enable mode is enabled,
Timer1/3/5 will increment on the rising edge of the
Timer1/3/5 clock source. When Timer1/3/5 Gate
Enable mode is disabled, no incrementing will occur
and Timer1/3/5 will hold the current count. See
Figure 12-4 for timing details.
TABLE 12-3:
TIMER1/3/5 GATE ENABLE
SELECTIONS
Timer1/3/5
Operation
TxCLK
TxGPOL
TxG

0
0
Counts

0
1
Holds Count

1
0
Holds Count

1
1
Counts
DS41412C-page 164
TIMER1/3/5 GATE SOURCES
Timer1/3/5 Gate Source
00
Timer1/3/5 Gate Pin
01
Timer2/4/6 Match to PR2/4/6
(TMR2/4/6 increments to match PR2/4/6)
10
Comparator 1 Output SYNCC1OUT
(optionally Timer1/3/5 synchronized output)
11
Comparator 2 Output SYNCC2OUT
(optionally Timer1/3/5 synchronized output)
Internal Data Bus
12.7
TIMER1/3/5 GATE SOURCE
SELECTION
The Gate resource, Timer2 Match to PR2, changes
between Timer2, Timer4 and Timer6 depending on
which of the three 16-bit Timers, Timer1, Timer3 or
Timer5, is selected. See Table 12-5 to determine which
Timer2/4/6 Match to PR2/4/6 combination is available
for the 16-bit timer being used.
TABLE 12-5:
GATE RESOURCES FOR
TIMER2/4/6 MATCH TO
PR2/4/6
Timer1/3/5 Resource
Timer1/3/5 Gate Match
Selection
Timer1
TMR2 Match to PR2
Timer3
TMR4 Match to PR4
Timer5
TMR6 Match to PR6
12.7.2.1
TxG Pin Gate Operation
The TxG pin is one source for Timer1/3/5 Gate Control.
It can be used to supply an external source to the
Timer1/3/5 Gate circuitry.
12.7.2.2
Timer2/4/6 Match Gate Operation
The TMR2/4/6 register will increment until it matches
the value in the PR2/4/6 register. On the very next
increment cycle, TMR2/4/6 will be reset to 00h. When
this Reset occurs, a low-to-high pulse will automatically
be generated and internally supplied to the Timer1/3/5
Gate circuitry. See Section 12.7.2 “Timer1/3/5 Gate
Source Selection” for more information.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
12.7.2.3
Comparator C1 Gate Operation
12.7.4
The output resulting from a Comparator 1 operation can
be selected as a source for Timer1/3/5 Gate Control.
The Comparator 1 output (SYNCC1OUT) can be
synchronized to the Timer1/3/5 clock or left
asynchronous. For more information see Section 18.8.4
“Synchronizing Comparator Output to Timer1”.
12.7.2.4
Comparator C2 Gate Operation
The output resulting from a Comparator 2 operation
can be selected as a source for Timer1/3/5 Gate
Control. The Comparator 2 output (SYNCC2OUT) can
be synchronized to the Timer1/3/5 clock or left
asynchronous.
For
more
information
see
Section 18.8.4 “Synchronizing Comparator Output
to Timer1”.
12.7.3
TIMER1/3/5 GATE TOGGLE MODE
When Timer1/3/5 Gate Toggle mode is enabled, it is
possible to measure the full-cycle length of a
Timer1/3/5 gate signal, as opposed to the duration of a
single level pulse.
The Timer1/3/5 Gate source is routed through a flip-flop
that changes state on every incrementing edge of the
signal. See Figure 12-5 for timing details.
Timer1/3/5 Gate Toggle mode is enabled by setting the
TxGTM bit of the TxGCON register. When the TxGTM
bit is cleared, the flip-flop is cleared and held clear. This
is necessary in order to control which edge is
measured.
Note:
Enabling Toggle mode at the same time as
changing the gate polarity may result in
indeterminate operation.
TIMER1/3/5 GATE SINGLE-PULSE
MODE
When Timer1/3/5 Gate Single-Pulse mode is enabled,
it is possible to capture a single-pulse gate event.
Timer1/3/5 Gate Single-Pulse mode is first enabled by
setting the TxGSPM bit in the TxGCON register. Next,
the TxGGO/DONE bit in the TxGCON register must be
set. The Timer1/3/5 will be fully enabled on the next
incrementing edge. On the next trailing edge of the
pulse, the TxGGO/DONE bit will automatically be
cleared. No other gate events will be allowed to
increment Timer1/3/5 until the TxGGO/DONE bit is
once again set in software.
Clearing the TxGSPM bit of the TxGCON register will
also clear the TxGGO/DONE bit. See Figure 12-6 for
timing details.
Enabling the Toggle mode and the Single-Pulse mode
simultaneously will permit both sections to work
together. This allows the cycle times on the Timer1/3/5
Gate source to be measured. See Figure 12-7 for
timing details.
12.7.5
TIMER1/3/5 GATE VALUE STATUS
When Timer1/3/5 Gate Value Status is utilized, it is
possible to read the most current level of the gate
control value. The value is stored in the TxGVAL bit in
the TxGCON register. The TxGVAL bit is valid even
when the Timer1/3/5 Gate is not enabled (TMRxGE bit
is cleared).
12.7.6
TIMER1/3/5 GATE EVENT
INTERRUPT
When Timer1/3/5 Gate Event Interrupt is enabled, it is
possible to generate an interrupt upon the completion
of a gate event. When the falling edge of TxGVAL
occurs, the TMRxGIF flag bit in the PIR3 register will be
set. If the TMRxGIE bit in the PIE3 register is set, then
an interrupt will be recognized.
The TMRxGIF flag bit operates even when the
Timer1/3/5 Gate is not enabled (TMRxGE bit is
cleared).
For more information on selecting high or low priority
status for the Timer1/3/5 Gate Event Interrupt see
Section 9.0 “Interrupts”.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 165
PIC18(L)F2X/4XK22
12.8
Timer1/3/5 Interrupt
The Timer1/3/5 register pair (TMRxH:TMRxL)
increments to FFFFh and rolls over to 0000h. When
Timer1/3/5 rolls over, the Timer1/3/5 interrupt flag bit of
the PIR1/2/5 register is set. To enable the interrupt on
rollover, you must set these bits:
•
•
•
•
TMRxON bit of the TxCON register
TMRxIE bits of the PIE1, PIE2 or PIE5 registers
PEIE/GIEL bit of the INTCON register
GIE/GIEH bit of the INTCON register
The interrupt is cleared by clearing the TMRxIF bit in
the Interrupt Service Routine.
For more information on selecting high or low priority
status for the Timer1/3/5 Overflow Interrupt, see
Section 9.0 “Interrupts”.
Note:
12.9
The TMRxH:TMRxL register pair and the
TMRxIF bit should be cleared before
enabling interrupts.
Timer1/3/5 Operation During Sleep
Timer1/3/5 can only operate during Sleep when setup
in Asynchronous Counter mode. In this mode, an
external crystal or clock source can be used to
increment the counter. To set up the timer to wake the
device:
•
•
•
•
•
TMRxON bit of the TxCON register must be set
TMRxIE bit of the PIE1/2/5 register must be set
PEIE/GIEL bit of the INTCON register must be set
TxSYNC bit of the TxCON register must be set
TMRxCS bits of the TxCON register must be
configured
• TxSOSCEN bit of the TxCON register must be
configured
12.10 ECCP/CCP Capture/Compare Time
Base
The CCP modules use the TMRxH:TMRxL register pair
as the time base when operating in Capture or
Compare mode.
In Capture mode, the value in the TMRxH:TMRxL
register pair is copied into the CCPRxH:CCPRxL
register pair on a configured event.
In Compare mode, an event is triggered when the value
CCPRxH:CCPRxL register pair matches the value in
the TMRxH:TMRxL register pair. This event can be a
Special Event Trigger.
For
more
information,
see
“Capture/Compare/PWM Modules”.
Section 14.0
12.11 ECCP/CCP Special Event Trigger
When any of the CCP’s are configured to trigger a
special event, the trigger will clear the TMRxH:TMRxL
register pair. This special event does not cause a
Timer1/3/5 interrupt. The CCP module may still be
configured to generate a CCP interrupt.
In this mode of operation, the CCPRxH:CCPRxL
register pair becomes the period register for
Timer1/3/5.
Timer1/3/5 should be synchronized and FOSC/4 should
be selected as the clock source in order to utilize the
Special Event Trigger. Asynchronous operation of
Timer1/3/5 can cause a Special Event Trigger to be
missed.
In the event that a write to TMRxH or TMRxL coincides
with a Special Event Trigger from the CCP, the write will
take precedence.
For more information, see Section 17.2.8 “Special
Event Trigger”.
The device will wake-up on an overflow and execute
the next instruction. If the GIE/GIEH bit of the INTCON
register is set, the device will call the Interrupt Service
Routine.
The secondary oscillator will continue to operate in
Sleep regardless of the TxSYNC bit setting.
DS41412C-page 166
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 12-3:
TIMER1/3/5 INCREMENTING EDGE
TXCKI = 1
when TMRx
Enabled
TXCKI = 0
when TMRX
Enabled
Note 1:
2:
Arrows indicate counter increments.
In Counter mode, a falling edge must be registered by the counter prior to the first incrementing rising edge of the clock.
FIGURE 12-4:
TIMER1/3/5 GATE ENABLE MODE
TMRxGE
TxGPOL
TxG_IN
TxCKI
TxGVAL
Timer1/3/5
N
 2010 Microchip Technology Inc.
N+1
Preliminary
N+2
N+3
N+4
DS41412C-page 167
PIC18(L)F2X/4XK22
FIGURE 12-5:
TIMER1/3/5 GATE TOGGLE MODE
TMRxGE
TxGPOL
TxGTM
TxTxG_IN
TxCKI
TxGVAL
TIMER1/3/5
FIGURE 12-6:
N
N+1 N+2 N+3
N+4
N+5 N+6 N+7
N+8
TIMER1/3/5 GATE SINGLE-PULSE MODE
TMRxGE
TxGPOL
TxGSPM
TxGGO/
Cleared by hardware on
falling edge of TxGVAL
Set by software
DONE
Counting enabled on
rising edge of TxG
TxG_IN
TxCKI
TxGVAL
TIMER1/3/5
TMRxGIF
DS41412C-page 168
N
N+1
N+2
Set by hardware on
falling edge of TxGVAL
Cleared by software
Preliminary
Cleared by
software
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 12-7:
TIMER1/3/5 GATE SINGLE-PULSE AND TOGGLE COMBINED MODE
TMRxGE
TxGPOL
TxGSPM
TxGTM
TxGGO/
Cleared by hardware on
falling edge of TxGVAL
Set by software
DONE
Counting enabled on
rising edge of TxG
TxG_IN
TxCKI
TxGVAL
TIMER1/3/5
TMRxGIF
N
N+1
N+2
N+3
Set by hardware on
falling edge of TxGVAL
Cleared by software
N+4
Cleared by
software
12.12 Peripheral Module Disable
When a peripheral module is not used or inactive, the
module can be disabled by setting the Module Disable
bit in the PMD registers. This will reduce power consumption to an absolute minimum. Setting the PMD
bits holds the module in Reset and disconnects the
module’s clock source. The Module Disable bits for
Timer1 (TMR1MD), Timer3 (TMR3MD) and Timer5
(TMR5MD) are in the PMD0 Register. See Section 3.0
“Power-Managed Modes” for more information.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 169
PIC18(L)F2X/4XK22
12.13 Timer1/3/5 Control Register
The Timer1/3/5 Control register (TxCON), shown in
Register 12-1, is used to control Timer1/3/5 and select
the various features of the Timer1/3/5 module.
REGISTER 12-1:
R/W-0/u
TXCON: TIMER1/3/5 CONTROL REGISTER
R/W-0/u
TMRxCS<1:0>
R/W-0/u
R/W-0/u
TxCKPS<1:0>
R/W-0/u
R/W-0/u
R/W-0/0
R/W-0/u
TxSOSCEN
TxSYNC
TxRD16
TMRxON
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
TMRxCS<1:0>: Timer1/3/5 Clock Source Select bits
11 = Reserved. Do not use.
10 = Timer1/3/5 clock source is pin or oscillator:
If TxSOSCEN = 0:
External clock from TxCKI pin (on the rising edge)
If TxSOSCEN = 1:
Crystal oscillator on SOSCI/SOSCO pins
01 = Timer1/3/5 clock source is system clock (FOSC)
00 = Timer1/3/5 clock source is instruction clock (FOSC/4)
bit 5-4
TxCKPS<1:0>: Timer1/3/5 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
TxSOSCEN: Secondary Oscillator Enable Control bit
1 = Dedicated Secondary oscillator circuit enabled
0 = Dedicated Secondary oscillator circuit disabled
bit 2
TxSYNC: Timer1/3/5 External Clock Input Synchronization Control bit
TMRxCS<1:0> = 1X
1 = Do not synchronize external clock input
0 = Synchronize external clock input with system clock (FOSC)
TMRxCS<1:0> = 0X
This bit is ignored. Timer1/3/5 uses the internal clock when TMRxCS<1:0> = 1X.
bit 1
TxRD16: 16-Bit Read/Write Mode Enable bit
1 = Enables register read/write of Timer1/3/5 in one 16-bit operation
0 = Enables register read/write of Timer1/3/5 in two 8-bit operation
bit 0
TMRxON: Timer1/3/5 On bit
1 = Enables Timer1/3/5
0 = Stops Timer1/3/5
Clears Timer1/3/5 Gate flip-flop
DS41412C-page 170
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
12.14 Timer1/3/5 Gate Control Register
The Timer1/3/5 Gate Control register (TxGCON),
shown in Register 12-2, is used to control Timer1/3/5
Gate.
REGISTER 12-2:
TXGCON: TIMER1/3/5 GATE CONTROL REGISTER
R/W-0/u
R/W-0/u
R/W-0/u
R/W-0/u
R/W/HC-0/u
R-x/x
TMRxGE
TxGPOL
TxGTM
TxGSPM
TxGGO/DONE
TxGVAL
R/W-0/u
R/W-0/u
TxGSS<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
HC = Bit is cleared by hardware
bit 7
TMRxGE: Timer1/3/5 Gate Enable bit
If TMRxON = 0:
This bit is ignored
If TMRxON = 1:
1 = Timer1/3/5 counting is controlled by the Timer1/3/5 gate function
0 = Timer1/3/5 counts regardless of Timer1/3/5 gate function
bit 6
TxGPOL: Timer1/3/5 Gate Polarity bit
1 = Timer1/3/5 gate is active-high (Timer1/3/5 counts when gate is high)
0 = Timer1/3/5 gate is active-low (Timer1/3/5 counts when gate is low)
bit 5
TxGTM: Timer1/3/5 Gate Toggle Mode bit
1 = Timer1/3/5 Gate Toggle mode is enabled
0 = Timer1/3/5 Gate Toggle mode is disabled and toggle flip-flop is cleared
Timer1/3/5 gate flip-flop toggles on every rising edge.
bit 4
TxGSPM: Timer1/3/5 Gate Single-Pulse Mode bit
1 = Timer1/3/5 gate Single-Pulse mode is enabled and is controlling Timer1/3/5 gate
0 = Timer1/3/5 gate Single-Pulse mode is disabled
bit 3
TxGGO/DONE: Timer1/3/5 Gate Single-Pulse Acquisition Status bit
1 = Timer1/3/5 gate single-pulse acquisition is ready, waiting for an edge
0 = Timer1/3/5 gate single-pulse acquisition has completed or has not been started
This bit is automatically cleared when TxGSPM is cleared.
bit 2
TxGVAL: Timer1/3/5 Gate Current State bit
Indicates the current state of the Timer1/3/5 gate that could be provided to TMRxH:TMRxL.
Unaffected by Timer1/3/5 Gate Enable (TMRxGE).
bit 1-0
TxGSS<1:0>: Timer1/3/5 Gate Source Select bits
00 = Timer1/3/5 Gate pin
01 = Timer2/4/6 Match PR2/4/6 output (See Table 12-6 for proper timer match selection)
10 = Comparator 1 optionally synchronized output (SYNCC1OUT)
11 = Comparator 2 optionally synchronized output (SYNCC2OUT)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 171
PIC18(L)F2X/4XK22
TABLE 12-6:
Name
ANSELB
REGISTERS ASSOCIATED WITH TIMER1/3/5 AS A TIMER/COUNTER
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values on
Page
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
ANSB0
153
153
ANSELC
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
IPR5
—
—
—
—
—
TMR6IP
TMR5IP
TMR4IP
130
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIE5
—
—
—
—
—
TMR6IE
TMR5IE
TMR4IE
126
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
—
—
122
PIR5
—
PMD0
UART2MD
T1CON
T1GCON
TMR1CS<1:0>
TMR1GE
T3CON
T3GCON
T1GPOL
TMR3CS<1:0>
TMR3GE
T5CON
T5GCON
UART1MD TMR6MD
T3GPOL
TMR5CS<1:0>
TMR5GE
T5GPOL
—
—
TMR6IF
TMR5IF
TMR4IF
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
T1SOSCEN
T1SYNC
T1RD16
TMR1ON
170
T1CKPS<1:0>
T1GTM
T1GSPM
T3CKPS<1:0>
T3GTM
T3GSPM
T5CKPS<1:0>
T5GTM
T5GSPM
T1GGO/DONE
T1GVAL
T3SOSCEN
T3SYNC
T3GGO/DONE
T3GVAL
T5SOSCEN
T5SYNC
T5GGO/DONE
T5GVAL
T1GSS<1:0>
T3RD16
TMR3ON
T3GSS
T5RD16
171
170
171
TMR5ON
T5GSS
170
171
TMRxH
Timer1/3/5 Register, High Byte
—
TMRxL
Timer1/3/5 Register, Low Byte
—
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TABLE 12-7:
CONFIGURATION REGISTERS ASSOCIATED WITH TIMER1/3/5
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
DS41412C-page 172
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
13.0
TIMER2/4/6 MODULE
There are three identical 8-bit Timer2-type modules
available. To maintain pre-existing naming conventions,
the Timers are called Timer2, Timer4 and Timer6 (also
Timer2/4/6).
Note:
The ‘x’ variable used in this section is used
to designate Timer2, Timer4, or Timer6.
For example, TxCON references T2CON,
T4CON, or T6CON. PRx references PR2,
PR4, or PR6.
The Timer2/4/6 module incorporates the following
features:
• 8-bit Timer and Period registers (TMRx and PRx,
respectively)
• Readable and writable (both registers)
• Software programmable prescaler (1:1, 1:4, 1:16)
• Software programmable postscaler (1:1 to 1:16)
• Interrupt on TMRx match with PRx, respectively
• Optional use as the shift clock for the MSSPx
modules (Timer2 only)
See Figure 13-1 for a block diagram of Timer2/4/6.
FIGURE 13-1:
TIMER2/4/6 BLOCK DIAGRAM
TMRx
Output
FOSC/4
Prescaler
1:1, 1:4, 1:16
2
TMRx
Comparator
Sets Flag
bit TMRxIF
Reset
Postscaler
1:1 to 1:16
EQ
TxCKPS<1:0>
4
PRx
TxOUTPS<3:0>
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 173
PIC18(L)F2X/4XK22
13.1
Timer2/4/6 Operation
13.2
The clock input to the Timer2/4/6 module is the system
instruction clock (FOSC/4).
TMRx increments from 00h on each clock edge.
A 4-bit counter/prescaler on the clock input allows direct
input, divide-by-4 and divide-by-16 prescale options.
These options are selected by the prescaler control bits,
TxCKPS<1:0> of the TxCON register. The value of
TMRx is compared to that of the Period register, PRx, 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 TMRx to 00h
on the next cycle and drives the output
counter/postscaler (see Section 13.2 “Timer2/4/6
Interrupt”).
The TMRx and PRx registers are both directly readable
and writable. The TMRx register is cleared on any
device Reset, whereas the PRx register initializes to
FFh. Both the prescaler and postscaler counters are
cleared on the following events:
•
•
•
•
•
•
•
•
•
a write to the TMRx register
a write to the TxCON register
Power-on Reset (POR)
Brown-out Reset (BOR)
MCLR Reset
Watchdog Timer (WDT) Reset
Stack Overflow Reset
Stack Underflow Reset
RESET Instruction
Note:
Timer2/4/6 Interrupt
Timer2/4/6 can also generate an optional device
interrupt. The Timer2/4/6 output signal (TMRx-to-PRx
match)
provides
the
input
for
the
4-bit
counter/postscaler. This counter generates the TMRx
match interrupt flag which is latched in TMRxIF of the
PIR1/PIR5 registers. The interrupt is enabled by setting
the TMRx Match Interrupt Enable bit, TMRxIE of the
PIE1/PIE5 registers. Interrupt Priority is selected with
the TMRxIP bit in the IPR1/IPR5 registers.
A range of 16 postscale options (from 1:1 through 1:16
inclusive) can be selected with the postscaler control
bits, TxOUTPS<3:0>, of the TxCON register.
13.3
Timer2/4/6 Output
The unscaled output of TMRx is available primarily to
the CCP modules, where it is used as a time base for
operations in PWM mode. The timer to be used with a
specific CCP module is selected using the
CxTSEL<1:0> bits in the CCPTMRS0 and CCPTMRS1
registers.
Timer2 can be optionally used as the shift clock source
for the MSSPx modules operating in SPI mode by
setting SSPM<3:0> = 0011 in the SSPxCON1 register.
Additional information is provided in Section 15.0
“Master Synchronous Serial Port (MSSP1 and
MSSP2) Module”.
13.4
TMRx is not cleared when TxCON is written.
Timer2/4/6 Operation During Sleep
The Timer2/4/6 timers cannot be operated while the
processor is in Sleep mode. The contents of the TMRx
and PRx registers will remain unchanged while the
processor is in Sleep mode.
13.5
Peripheral Module Disable
When a peripheral module is not used or inactive, the
module can be disabled by setting the Module Disable
bit in the PMD registers. This will reduce power consumption to an absolute minimum. Setting the PMD
bits holds the module in Reset and disconnects the
module’s clock source. The Module Disable bits for
Timer2 (TMR2MD), Timer4 (TMR4MD) and Timer6
(TMR6MD) are in the PMD0 Register. See Section 3.0
“Power-Managed Modes” for more information.
DS41412C-page 174
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 13-1:
U-0
TxCON: TIMER2/TIMER4/TIMER6 CONTROL REGISTER
R/W-0
—
R/W-0
R/W-0
R/W-0
TxOUTPS<3:0>
R/W-0
R/W-0
TMRxON
bit 7
R/W-0
TxCKPS<1:0>
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
Unimplemented: Read as ‘0’
bit 6-3
TxOUTPS<3:0>: TimerX Output Postscaler Select bits
0000 = 1:1 Postscaler
0001 = 1:2 Postscaler
0010 = 1:3 Postscaler
0011 = 1:4 Postscaler
0100 = 1:5 Postscaler
0101 = 1:6 Postscaler
0110 = 1:7 Postscaler
0111 = 1:8 Postscaler
1000 = 1:9 Postscaler
1001 = 1:10 Postscaler
1010 = 1:11 Postscaler
1011 = 1:12 Postscaler
1100 = 1:13 Postscaler
1101 = 1:14 Postscaler
1110 = 1:15 Postscaler
1111 = 1:16 Postscaler
bit 2
TMRxON: TimerX On bit
1 = TimerX is on
0 = TimerX is off
bit 1-0
TxCKPS<1:0>: Timer2-type Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 175
PIC18(L)F2X/4XK22
TABLE 13-1:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH TIMER2/4/6
Bit 7
CCPTMRS0
Bit 6
C3TSEL<1:0>
Bit 5
—
Bit 4
Bit 3
C2TSEL<1:0>
—
—
—
—
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
IPR1
—
ADIP
RC1IP
TX1IP
IPR5
—
—
—
—
PIE1
—
ADIE
RC1IE
TX1IE
CCPTMRS1
INTCON
Bit 2
—
C5TSEL<1:0>
Bit 1
Bit 0
Register
on Page
C1TSEL<1:0>
204
C4TSEL<1:0>
204
TMR0IF
INT0IF
RBIF
115
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
—
TMR6IP
TMR5IP
TMR4IP
130
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
126
PIE5
—
—
—
—
—
TMR6IE
TMR5IE
TMR4IE
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR5
—
—
—
—
—
TMR6IF
TMR5IF
TMR4IF
122
TMR1MD
56
PMD0
UART2MD UART1MD
TMR6MD TMR5MD TMR4MD TMR3MD TMR2MD
PR2
Timer2 Period Register
—
PR4
Timer4 Period Register
—
PR6
Timer6 Period Register
—
T2CON
—
T2OUTPS<3:0>
TMR2ON
T2CKPS<1:0>
170
T4CON
—
T4OUTPS<3:0>
TMR4ON
T4CKPS<1:0>
170
T6CON
—
T6OUTPS<3:0>
TMR6ON
T6CKPS<1:0>
170
TMR2
Timer2 Register
—
TMR4
Timer4 Register
—
TMR6
Timer6 Register
—
Legend:
— = unimplemented locations, read as ‘0’. Shaded bits are not used by Timer2/4/6.
DS41412C-page 176
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.0
CAPTURE/COMPARE/PWM
MODULES
The Capture/Compare/PWM module is a peripheral
which allows the user to time and control different
events, and to generate Pulse-Width Modulation
(PWM) signals. In Capture mode, the peripheral allows
the timing of the duration of an event. The Compare
mode allows the user to trigger an external event when
a predetermined amount of time has expired. The
PWM mode can generate Pulse-Width Modulated
signals of varying frequency and duty cycle.
Note 1: In devices with more than one CCP
module, it is very important to pay close
attention to the register names used. A
number placed after the module acronym
is used to distinguish between separate
modules. For example, the CCP1CON
and CCP2CON control the same
operational aspects of two completely
different CCP modules.
2: Throughout
this
section,
generic
references to a CCP module in any of its
operating modes may be interpreted as
being equally applicable to ECCP1,
ECCP2, ECCP3, CCP4 and CCP5.
Register names, module signals, I/O pins,
and bit names may use the generic
designator ‘x’ to indicate the use of a
numeral to distinguish a particular module,
when required.
This family of devices contains three Enhanced
Capture/Compare/PWM modules (ECCP1, ECCP2,
and ECCP3) and two standard Capture/Compare/PWM
modules (CCP4 and CCP5).
The Capture and Compare functions are identical for all
CCP/ECCP modules. The difference between CCP
and ECCP modules are in the Pulse-Width Modulation
(PWM) function. In CCP modules, the standard PWM
function is identical. In ECCP modules, the Enhanced
PWM function has either Full-Bridge or Half-Bridge
PWM output. Full-Bridge ECCP modules have four
available I/O pins while Half-Bridge ECCP modules
only have two available I/O pins. ECCP PWM modules
are backward compatible with CCP PWM modules and
can be configured as standard PWM modules. See
Table 14-1 to determine the CCP/ECCP functionality
available on each device in this family.
TABLE 14-1:
Device Name
PWM RESOURCES
ECCP1
ECCP2
PIC18(L)F23K22
PIC18(L)F24K22
PIC18(L)F25K22
PIC18(L)F26K22
Enhanced PWM
Full-Bridge
Enhanced PWM
Half-Bridge
Enhanced PWM
Standard PWM
Standard PWM
Half-Bridge
(Special Event Trigger)
PIC18(L)F43K22
PIC18(L)F44K22
PIC18(L)F45K22
PIC18(L)F46K22
Enhanced PWM
Full-Bridge
Enhanced PWM
Full-Bridge
Enhanced PWM
Standard PWM
Standard PWM
Half-Bridge
(Special Event Trigger)
 2010 Microchip Technology Inc.
ECCP3
Preliminary
CCP4
CCP5
DS41412C-page 177
PIC18(L)F2X/4XK22
14.1
Capture Mode
The Capture mode function described in this section is
identical for all CCP and ECCP modules available on
this device family.
Capture mode makes use of the 16-bit Timer
resources, Timer1, Timer3 and Timer5. The timer
resources for each CCP capture function are
independent and are selected using the CCPTMRS0
and CCPTMRS1 registers. When an event occurs on
the CCPx pin, the 16-bit CCPRxH:CCPRxL register
pair captures and stores the 16-bit value of the
TMRxH:TMRxL register pair, respectively. An event is
defined as one of the following and is configured by the
CCPxM<3:0> bits of the CCPxCON register:
•
•
•
•
Every falling edge
Every rising edge
Every 4th rising edge
Every 16th rising edge
Figure 14-1 shows a simplified diagram of the Capture
operation.
FIGURE 14-1:
Prescaler
 1, 4, 16
CCPRxH
CCPRxL
Capture
Enable
and
Edge Detect
TMR1/3/5H TMR1/3/5L
CCPxM<3:0>
System Clock (FOSC)
CCP PIN CONFIGURATION
In Capture mode, the CCPx pin should be configured
as an input by setting the associated TRIS control bit.
Some CCPx outputs are multiplexed on a couple of
pins. Table 14-2 shows the CCP output pin
multiplexing. Selection of the output pin is determined
by the CCPxMX bits in Configuration register 3H
(CONFIG3H). Refer to Register 24-4 for more details.
Note:
TABLE 14-2:
Set Flag bit CCPxIF
(PIR1/2/4 register)
CCPx
pin
14.1.1
When a capture is made, the corresponding Interrupt
Request Flag bit CCPxIF of the PIR1, PIR2 or PIR4
register is set. The interrupt flag must be cleared in
software. If another capture occurs before the value in
the CCPRxH:CCPRxL register pair is read, the old
captured value is overwritten by the new captured
value.
CAPTURE MODE
OPERATION BLOCK
DIAGRAM
If the CCPx pin is configured as an output,
a write to the port can cause a capture
condition.
CCP PIN MULTIPLEXING
CCP OUTPUT
CONFIG 3H Control Bit
CCP2
CCP2MX
CCP3
CCP3MX
Bit Value
PIC18(L)F2XK22 I/O pin
PIC18(L)F4XK22 I/O pin
0
RB3
RB3
(*)
1
RC1
RC1
0(*)
RC6
RE0
1
RB5
RB5
Legend: * = Default
14.1.2
TIMER1 MODE RESOURCE
14.1.3
The 16-bit Timer resource must be running in Timer
mode or Synchronized Counter mode for the CCP
module to use the capture feature. In Asynchronous
Counter mode, the capture operation may not work.
See Section 12.0 “Timer1/3/5 Module with Gate
Control” for more information on configuring the 16-bit
Timers.
Note:
DS41412C-page 178
SOFTWARE INTERRUPT MODE
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep the
CCPxIE interrupt enable bit of the PIE1, PIE2 or PIE4
register clear to avoid false interrupts. Additionally, the
user should clear the CCPxIF interrupt flag bit of the
PIR1, PIR2 or PIR4 register following any change in
Operating mode.
Preliminary
Clocking the 16-bit Timer resource from
the system clock (FOSC) should not be
used in Capture mode. In order for
Capture mode to recognize the trigger
event on the CCPx pin, the Timer resource
must be clocked from the instruction clock
(FOSC/4) or from an external clock source.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.1.4
CCP PRESCALER
14.1.5
There are four prescaler settings specified by the
CCPxM<3:0> bits of the CCPxCON register. Whenever
the CCP module is turned off, or the CCP module is not
in Capture mode, the prescaler counter is cleared. Any
Reset will clear the prescaler counter.
Capture mode requires a 16-bit TimerX module for use
as a time base. There are four options for driving the
16-bit TimerX module in Capture mode. It can be driven
by the system clock (FOSC), the instruction clock (FOSC/
4), or by the external clock sources, the Secondary
Oscillator (SOSC), or the TxCKI clock input. When the
16-bit TimerX resource is clocked by FOSC or FOSC/4,
TimerX will not increment during Sleep. When the
device wakes from Sleep, TimerX will continue from its
previous state. Capture mode will operate during Sleep
when the 16-bit TimerX resource is clocked by one of
the external clock sources (SOSC or the TxCKI pin).
Switching from one capture prescaler to another does
not clear the prescaler and may generate a false
interrupt. To avoid this unexpected operation, turn the
module off by clearing the CCPxCON register before
changing the prescaler. Example 14-1 demonstrates
the code to perform this function.
EXAMPLE 14-1:
CHANGING BETWEEN
CAPTURE PRESCALERS
#define NEW_CAPT_PS 0x06
//Capture
// Prescale 4th
// rising edge
// Turn the CCP
// Module Off
// Turn CCP module
// on with new
// prescale value
...
CCPxCON = 0;
CCPxCON = NEW_CAPT_PS;
TABLE 14-3:
Name
CAPTURE DURING SLEEP
REGISTERS ASSOCIATED WITH CAPTURE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CCP1CON
P1M<1:0>
DC1B<1:0>
CCP1M<3:0>
201
CCP2CON
P2M<1:0>
DC2B<1:0>
CCP2M<3:0>
201
CCP3CON
DC3B<1:0>
CCP3M<3:0>
201
CCP4CON
—
P3M<1:0>
—
DC4B<1:0>
CCP4M<3:0>
201
CCP5CON
—
—
DC5B<1:0>
CCP5M<3:0>
201
CCPR1H
Capture/Compare/PWM Register 1 High Byte (MSB)
—
CCPR1L
Capture/Compare/PWM Register 1 Low Byte (LSB)
—
CCPR2H
Capture/Compare/PWM Register 2 High Byte (MSB)
—
CCPR2L
Capture/Compare/PWM Register 2 Low Byte (LSB)
—
CCPR3H
Capture/Compare/PWM Register 3 High Byte (MSB)
—
CCPR3L
Capture/Compare/PWM Register 3 Low Byte (LSB)
—
CCPR4H
Capture/Compare/PWM Register 4 High Byte (MSB)
—
CCPR4L
Capture/Compare/PWM Register 4 Low Byte (LSB)
—
CCPR5H
Capture/Compare/PWM Register 5 High Byte (MSB)
—
CCPR5L
Capture/Compare/PWM Register 5 Low Byte (LSB)
CCPTMRS0
CCPTMRS1
C3TSEL<1:0>
—
C2TSEL<1:0>
—
204
C4TSEL<1:0>
204
—
—
—
—
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
130
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
INTCON
C5TSEL<1:0>
—
C1TSEL<1:0>
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 179
PIC18(L)F2X/4XK22
TABLE 14-3:
REGISTERS ASSOCIATED WITH CAPTURE (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
126
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
121
PMD0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
Name
T1CON
TMR1CS<1:0>
T1GCON
TMR1GE
T3CON
T1GPOL
T1CKPS<1:0>
T1GTM
TMR3CS<1:0>
T3GCON
TMR3GE
T5CON
T3GPOL
T3CKPS<1:0>
T3GTM
TMR5CS<1:0>
T5GCON
TMR5GE
T5GPOL
T1GSPM
T3GSPM
T5CKPS<1:0>
T5GTM
T5GSPM
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
T1SOSCEN
T1SYNC
T1RD16
TMR1ON
170
T1GGO/DONE
T1GVAL
T3SOSCEN
T3SYNC
T3GGO/DONE
T3GVAL
T5SOSCEN
T5SYNC
T5GGO/DONE
T5GVAL
T1GSS
T3RD16
TMR3ON
T3GSS
T5RD16
TMR5ON
T5GSS
171
170
171
170
171
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
—
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
—
TMR3H
Holding Register for the Most Significant Byte of the 16-bit TMR3 Register
—
TMR3L
Holding Register for the Least Significant Byte of the 16-bit TMR3 Register
—
TMR5H
Holding Register for the Most Significant Byte of the 16-bit TMR5 Register
—
TMR5L
Holding Register for the Least Significant Byte of the 16-bit TMR5 Register
—
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
TRISE
WPUE3
—
—
—
—
TRISE2(1)
TRISE1(1)
TRISE0(1)
154
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
TABLE 14-4:
CONFIGURATION REGISTERS ASSOCIATED WITH CAPTURE
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
DS41412C-page 180
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.2
Compare Mode
14.2.1
The Compare mode function described in this section
is identical for all CCP and ECCP modules available on
this device family.
Compare mode makes use of the 16-bit TimerX
resources, Timer1, Timer3 and Timer5. The 16-bit
value of the CCPRxH:CCPRxL register pair is
constantly compared against the 16-bit value of the
TMRxH:TMRxL register pair. When a match occurs,
one of the following events can occur:
•
•
•
•
•
Toggle the CCPx output
Set the CCPx output
Clear the CCPx output
Generate a Special Event Trigger
Generate a Software Interrupt
All Compare modes can generate an interrupt.
Figure 14-2 shows a simplified diagram of the
Compare operation.
FIGURE 14-2:
The user must configure the CCPx pin as an output by
clearing the associated TRIS bit.
Some CCPx outputs are multiplexed on a couple of
pins. Table 14-2 shows the CCP output pin
Multiplexing. Selection of the output pin is determined
by the CCPxMX bits in Configuration register 3H
(CONFIG3H). Refer to Register 24-4 for more details.
Note:
14.2.2
The action on the pin is based on the value of the
CCPxM<3:0> control bits of the CCPxCON register. At
the same time, the interrupt flag CCPxIF bit is set.
Q
S
R
Output
Logic
Match
TRIS
Output Enable
Comparator
TMRxH
TimerX MODE RESOURCE
See Section 12.0 “Timer1/3/5 Module with Gate
Control” for more information on configuring the 16-bit
TimerX resources.
Note:
CCPxM<3:0>
Mode Select
CCPx
Pin
Clearing the CCPxCON register will force
the CCPx compare output latch to the
default low level. This is not the PORT I/O
data latch.
In Compare mode, 16-bit TimerX resource must be
running in either Timer mode or Synchronized Counter
mode. The compare operation may not work in
Asynchronous Counter mode.
COMPARE MODE
OPERATION BLOCK
DIAGRAM
Set CCPxIF Interrupt Flag
(PIR1/2/4)
4
CCPRxH CCPRxL
CCP PIN CONFIGURATION
14.2.3
Clocking TimerX from the system clock
(FOSC) should not be used in Compare
mode. In order for Compare mode to
recognize the trigger event on the CCPx
pin, TImerX must be clocked from the
instruction clock (FOSC/4) or from an
external clock source.
SOFTWARE INTERRUPT MODE
When Generate Software Interrupt mode is chosen
(CCPxM<3:0> = 1010), the CCPx module does not
assert control of the CCPx pin (see the CCPxCON
register).
TMRxL
Special Event Trigger
Special Event Trigger function on
• ECCP1, ECCP2, ECCP3, CCP4 and CCP5 will:
- Reset TimerX – TMRxH:TMRxL = 0x0000
- TimerX Interrupt Flag, (TMRxIF) is not set
Additional Function on
• CCP5 will
- Set ADCON0<1>, GO/DONE bit to start an ADC
Conversion if ADCON<0>, ADON = 1.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 181
PIC18(L)F2X/4XK22
14.2.4
SPECIAL EVENT TRIGGER
14.2.5
When Special Event Trigger mode is selected
(CCPxM<3:0> = 1011), and a match of the
TMRxH:TMRxL and the CCPRxH:CCPRxL registers
occurs, all CCPx and ECCPx modules will immediately:
COMPARE DURING SLEEP
The Compare mode is dependent upon the system
clock (FOSC) for proper operation. Since FOSC is shut
down during Sleep mode, the Compare mode will not
function properly during Sleep.
• Set the CCP interrupt flag bit – CCPxIF
• CCP5 will start an ADC conversion, if the ADC is
enabled
On the next TimerX rising clock edge:
• A Reset of TimerX register pair occurs –
TMRxH:TMRxL = 0x0000,
This Special Event Trigger mode does not:
• Assert control over the CCPx or ECCPx pins.
• Set the TMRxIF interrupt bit when the
TMRxH:TMRxL register pair is reset. (TMRxIF
gets set on a TimerX overflow.)
If the value of the CCPRxH:CCPRxL registers are
modified when a match occurs, the user should be
aware that the automatic reset of TimerX occurs on the
next rising edge of the clock. Therefore, modifying the
CCPRxH:CCPRxL registers before this reset occurs
will allow the TimerX to continue without being reset,
inadvertently resulting in the next event being
advanced or delayed.
The Special Event Trigger mode allows the
CCPRxH:CCPRxL register pair to effectively provide a
16-bit programmable period register for TimerX.
TABLE 14-5:
Name
REGISTERS ASSOCIATED WITH COMPARE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CCP1CON
P1M<1:0>
DC1B<1:0>
CCP1M<3:0>
201
CCP2CON
P2M<1:0>
DC2B<1:0>
CCP2M<3:0>
201
CCP3CON
P3M<1:0>
DC3B<1:0>
CCP3M<3:0>
201
CCP4CON
—
—
DC4B<1:0>
CCP4M<3:0>
201
CCP5CON
—
—
DC5B<1:0>
CCP5M<3:0>
201
CCPR1H
Capture/Compare/PWM Register 1 High Byte (MSB)
—
CCPR1L
Capture/Compare/PWM Register 1 Low Byte (LSB)
—
CCPR2H
Capture/Compare/PWM Register 2 High Byte (MSB)
—
CCPR2L
Capture/Compare/PWM Register 2 Low Byte (LSB)
—
CCPR3H
Capture/Compare/PWM Register 3 High Byte (MSB)
—
CCPR3L
Capture/Compare/PWM Register 3 Low Byte (LSB)
—
CCPR4H
Capture/Compare/PWM Register 4 High Byte (MSB)
—
CCPR4L
Capture/Compare/PWM Register 4 Low Byte (LSB)
—
CCPR5H
Capture/Compare/PWM Register 5 High Byte (MSB)
—
CCPR5L
Capture/Compare/PWM Register 5 Low Byte (LSB)
CCPTMRS0
CCPTMRS1
INTCON
C3TSEL<1:0>
—
C2TSEL<1:0>
—
—
—
—
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
—
C5TSEL<1:0>
RBIE
TMR0IF
—
C1TSEL<1:0>
204
C4TSEL<1:0>
204
INT0IF
RBIF
115
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
DS41412C-page 182
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 14-5:
Name
REGISTERS ASSOCIATED WITH COMPARE (CONTINUED)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
130
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
126
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
121
PMD0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
T1SOSCEN
T1SYNC
T1RD16
TMR1ON
T1GGO/DONE
T1GVAL
T3SOSCEN
T3SYNC
T1CON
TMR1CS<1:0>
T1GCON
TMR1GE
T3CON
T1GPOL
T1CKPS<1:0>
T1GTM
TMR3CS<1:0>
T3GCON
TMR3GE
T5CON
T3GPOL
T3CKPS<1:0>
T3GTM
TMR5CS<1:0>
T5GCON
TMR5GE
T5GPOL
T1GSPM
T3GSPM
T5CKPS<1:0>
T5GTM
T5GSPM
T3GGO/DONE
T3GVAL
T5SOSCEN
T5SYNC
T5GGO/DONE
T5GVAL
T1GSS
T3RD16
TMR3ON
T3GSS
T5RD16
TMR5ON
T5GSS
170
171
170
171
170
171
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
—
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
—
TMR3H
Holding Register for the Most Significant Byte of the 16-bit TMR3 Register
—
TMR3L
Holding Register for the Least Significant Byte of the 16-bit TMR3 Register
—
TMR5H
Holding Register for the Most Significant Byte of the 16-bit TMR5 Register
—
TMR5L
Holding Register for the Least Significant Byte of the 16-bit TMR5 Register
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
—
TRISA0
154
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
TRISE
WPUE3
—
—
—
—
TRISE2(1)
TRISE1(1)
TRISE0(1)
154
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
TABLE 14-6:
CONFIGURATION REGISTERS ASSOCIATED WITH CAPTURE
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 183
PIC18(L)F2X/4XK22
14.3
PWM Overview
FIGURE 14-3:
Pulse-Width Modulation (PWM) is a scheme that
provides power to a load by switching quickly between
fully on and fully off states. The PWM signal resembles
a square wave where the high portion of the signal is
considered the on state and the low portion of the signal
is considered the off state. The high portion, also known
as the pulse width, can vary in time and is defined in
steps. A larger number of steps applied, which
lengthens the pulse width, also supplies more power to
the load. Lowering the number of steps applied, which
shortens the pulse width, supplies less power. The
PWM period is defined as the duration of one complete
cycle or the total amount of on and off time combined.
Period
Pulse Width
TMRx = 0
FIGURE 14-4:
CCPRxH(2) (Slave)
CCPx
TMRx
(1)
Q
S
TRIS
Comparator
PRx
Note 1:
The standard PWM mode generates a Pulse-Width
modulation (PWM) signal on the CCPx pin with up to 10
bits of resolution. The period, duty cycle, and resolution
are controlled by the following registers:
2:
14.3.2
Clear Timer,
toggle CCPx pin and
latch duty cycle
The 8-bit timer TMRx register is concatenated
with the 2-bit internal system clock (FOSC), or
2 bits of the prescaler, to create the 10-bit time
base.
In PWM mode, CCPRxH is a read-only register.
SETUP FOR PWM OPERATION
The following steps should be taken when configuring
the CCP module for standard PWM operation:
Figure 14-4 shows a simplified block diagram of PWM
operation.
Note 1: The corresponding TRIS bit must be
cleared to enable the PWM output on the
CCPx pin.
2: Clearing the CCPxCON register will
relinquish control of the CCPx pin.
1.
2.
3.
4.
5.
DS41412C-page 184
R
Comparator
STANDARD PWM OPERATION
PRx registers
TxCON registers
CCPRxL registers
CCPxCON registers
CCPxCON<5:4>
CCPRxL
Figure 14-3 shows a typical waveform of the PWM
signal.
•
•
•
•
SIMPLIFIED PWM BLOCK
DIAGRAM
Duty Cycle Registers
The term duty cycle describes the proportion of the on
time to the off time and is expressed in percentages,
where 0% is fully off and 100% is fully on. A lower duty
cycle corresponds to less power applied and a higher
duty cycle corresponds to more power applied.
The standard PWM function described in this section is
available and identical for CCP and ECCP modules.
TMRx = PRx
TMRx = CCPRxH:CCPxCON<5:4>
PWM resolution defines the maximum number of steps
that can be present in a single PWM period. A higher
resolution allows for more precise control of the pulse
width time and in turn the power that is applied to the
load.
14.3.1
CCP PWM OUTPUT SIGNAL
Preliminary
Disable the CCPx pin output driver by setting the
associated TRIS bit.
Select the 8-bit TimerX resource, (Timer2,
Timer4 or Timer6) to be used for PWM generation by setting the CxTSEL<1:0> bits in the
CCPTMRSx register.(1)
Load the PRx register for the selected TimerX
with the PWM period value.
Configure the CCP module for the PWM mode
by loading the CCPxCON register with the
appropriate values.
Load the CCPRxL register and the DCxB<1:0>
bits of the CCPxCON register, with the PWM
duty cycle value.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
6.
7.
14.3.5
Configure and start the 8-bit TimerX resource:
• Clear the TMRxIF interrupt flag bit of the
PIR2 or PIR4 register. See Note 1 below.
• Configure the TxCKPS bits of the TxCON
register with the Timer prescale value.
• Enable the Timer by setting the TMRxON
bit of the TxCON register.
Enable PWM output pin:
• Wait until the Timer overflows and the
TMRxIF bit of the PIR2 or PIR4 register is
set. See Note 1 below.
• Enable the CCPx pin output driver by
clearing the associated TRIS bit.
The PWM duty cycle is specified by writing a 10-bit
value to multiple registers: CCPRxL register and
DCxB<1:0> bits of the CCPxCON register. The
CCPRxL contains the eight MSbs and the DCxB<1:0>
bits of the CCPxCON register contain the two LSbs.
CCPRxL and DCxB<1:0> bits of the CCPxCON
register can be written to at any time. The duty cycle
value is not latched into CCPRxH until after the period
completes (i.e., a match between PRx and TMRx
registers occurs). While using the PWM, the CCPRxH
register is read-only.
Note 1: In order to send a complete duty cycle
and period on the first PWM output, the
above steps must be included in the
setup sequence. If it is not critical to start
with a complete PWM signal on the first
output, then step 6 may be ignored.
14.3.3
PWM DUTY CYCLE
Equation 14-2 is used to calculate the PWM pulse
width.
Equation 14-3 is used to calculate the PWM duty cycle
ratio.
EQUATION 14-2:
Pulse Width =  CCPRxL:CCPxCON<5:4>  
PWM TIMER RESOURCE
T OSC  (TMRx Prescale Value)
The PWM standard mode makes use of one of the 8-bit
Timer2/4/6 timer resources to specify the PWM period.
Configuring the CxTSEL<1:0> bits in the CCPTMRS0
or CCPTMRS1 register selects which Timer2/4/6 timer
is used.
14.3.4
PWM PERIOD
The PWM period is specified by the PRx register of 8-bit
TimerX. The PWM period can be calculated using the
formula of Equation 14-1.
EQUATION 14-1:
EQUATION 14-3:
DUTY CYCLE RATIO
 CCPRxL:CCPxCON<5:4> 
Duty Cycle Ratio = ----------------------------------------------------------------------4  PRx + 1 
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.
The 8-bit timer TMRx register is concatenated with either
the 2-bit internal system clock (FOSC), or 2 bits of the
prescaler, to create the 10-bit time base. The system
clock is used if the TimerX prescaler is set to 1:1.
PWM PERIOD
PWM Period =   PRx  + 1   4  T OSC 
(TMRx Prescale Value)
Note 1:
PULSE WIDTH
When the 10-bit time base matches the CCPRxH and
2-bit latch, then the CCPx pin is cleared (see
Figure 14-4).
TOSC = 1/FOSC
When TMRx is equal to PRx, the following three events
occur on the next increment cycle:
• TMRx is cleared
• The CCPx pin is set. (Exception: If the PWM duty
cycle = 0%, the pin will not be set.)
• The PWM duty cycle is latched from CCPRxL into
CCPRxH.
Note:
The Timer postscaler (see Section 13.0
“Timer2/4/6 Module”) is not used in the
determination of the PWM frequency.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 185
PIC18(L)F2X/4XK22
14.3.6
PWM RESOLUTION
EQUATION 14-4:
The resolution determines the number of available duty
cycles for a given period. For example, a 10-bit resolution
will result in 1024 discrete duty cycles, whereas an 8-bit
resolution will result in 256 discrete duty cycles.
The maximum PWM resolution is 10 bits when PRx is
255. The resolution is a function of the PRx register
value as shown by Equation 14-4.
TABLE 14-7:
Timer Prescale (1, 4, 16)
PRx Value
Maximum Resolution (bits)
Timer Prescale (1, 4, 16)
PRx Value
Maximum Resolution (bits)
Timer Prescale (1, 4, 16)
PRx Value
Maximum Resolution (bits)
1.95 kHz
7.81 kHz
31.25 kHz
125 kHz
250 kHz
333.3 kHz
16
4
1
1
1
1
0xFF
0xFF
0xFF
0x3F
0x1F
0x17
10
10
10
8
7
6.6
1.22 kHz
4.88 kHz
19.53 kHz
78.12 kHz
156.3 kHz
208.3 kHz
16
4
1
1
1
1
0xFF
0xFF
0xFF
0x3F
0x1F
0x17
10
10
10
8
7
6.6
1.22 kHz
4.90 kHz
19.61 kHz
76.92 kHz
153.85 kHz
200.0 kHz
16
4
1
1
1
1
0x65
0x65
0x65
0x19
0x0C
0x09
8
8
8
6
5
5
OPERATION IN SLEEP MODE
14.3.9
In Sleep mode, the TMRx register will not increment
and the state of the module will not change. If the CCPx
pin is driving a value, it will continue to drive that value.
When the device wakes up, TMRx will continue from its
previous state.
14.3.8
If the pulse width value is greater than the
period the assigned PWM pin(s) will
remain unchanged.
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 8 MHz)
PWM Frequency
14.3.7
Note:
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 20 MHz)
PWM Frequency
TABLE 14-9:
log  4  PRx + 1  
Resolution = ------------------------------------------ bits
log  2 
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 32 MHz)
PWM Frequency
TABLE 14-8:
PWM RESOLUTION
EFFECTS OF RESET
Any Reset will force all ports to Input mode and the
CCP registers to their Reset states.
CHANGES IN SYSTEM CLOCK
FREQUENCY
The PWM frequency is derived from the system clock
frequency. Any changes in the system clock frequency
will result in changes to the PWM frequency. See
Section 2.0 “Oscillator Module (With Fail-Safe
Clock Monitor)” for additional details.
DS41412C-page 186
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 14-10: REGISTERS ASSOCIATED WITH STANDARD PWM
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CCP1CON
P1M<1:0>
DC1B<1:0>
CCP1M<3:0>
201
CCP2CON
P2M<1:0>
DC2B<1:0>
CCP2M<3:0>
201
CCP3CON
P3M<1:0>
DC3B<1:0>
CCP3M<3:0>
201
201
CCP4CON
—
—
DC4B<1:0>
CCP4M<3:0>
CCP5CON
—
—
DC5B<1:0>
CCP5M<3:0>
CCPTMRS0
CCPTMRS1
C3TSEL<1:0>
—
C2TSEL<1:0>
—
204
C4TSEL<1:0>
204
—
—
—
—
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
128
INTCON
C5TSEL<1:0>
201
C1TSEL<1:0>
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
126
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
121
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
PMD0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
PR2
Timer2 Period Register
—
PR4
Timer4 Period Register
—
PR6
Timer6 Period Register
—
T2CON
—
T2OUTPS<3:0>
TMR2ON
T2CKPS<1:0>
170
T4CON
—
T4OUTPS<3:0>
TMR4ON
T4CKPS<1:0>
170
T6CON
—
T6OUTPS<3:0>
TMR6ON
T6CKPS<1:0>
170
TMR2
Timer2 Period Register
—
TMR4
Timer4 Period Register
—
TMR6
Timer6 Period Register
—
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD0
154
TRISE
WPUE3
—
—
—
—
TRISE0(1)
154
TRISD2
TRISD1
TRISE2(1)
TRISE1(1)
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
TABLE 14-11: CONFIGURATION REGISTERS ASSOCIATED WITH CAPTURE
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 187
PIC18(L)F2X/4XK22
14.4
PWM (Enhanced Mode)
To select an Enhanced PWM Output mode, the
PxM<1:0> bits of the CCPxCON register must be
configured appropriately.
The enhanced PWM function described in this section is
available for CCP modules ECCP1, ECCP2 and
ECCP3, with any differences between modules noted.
The PWM outputs are multiplexed with I/O pins and are
designated PxA, PxB, PxC and PxD. The polarity of the
PWM pins is configurable and is selected by setting the
CCPxM bits in the CCPxCON register appropriately.
The enhanced PWM mode generates a Pulse-Width
Modulation (PWM) signal on up to four different output
pins with up to 10 bits of resolution. The period, duty
cycle, and resolution are controlled by the following
registers:
•
•
•
•
Figure 14-5 shows an example of a simplified block
diagram of the Enhanced PWM module.
Table 14-12 shows the pin assignments for various
Enhanced PWM modes.
PRx registers
TxCON registers
CCPRxL registers
CCPxCON registers
Note 1: The corresponding TRIS bit must be
cleared to enable the PWM output on the
CCPx pin.
The ECCP modules have the following additional PWM
registers which control Auto-shutdown, Auto-restart,
Dead-band Delay and PWM Steering modes:
2: Clearing the CCPxCON register will
relinquish control of the CCPx pin.
3: Any pin not used in the enhanced PWM
mode is available for alternate pin
functions, if applicable.
• ECCPxAS registers
• PSTRxCON registers
• PWMxCON registers
4: To prevent the generation of an
incomplete waveform when the PWM is
first enabled, the ECCP module waits
until the start of a new PWM period before
generating a PWM signal.
The enhanced PWM module can generate the following
five PWM Output modes:
•
•
•
•
•
Single PWM
Half-Bridge PWM
Full-Bridge PWM, Forward Mode
Full-Bridge PWM, Reverse Mode
Single PWM with PWM Steering Mode
FIGURE 14-5:
EXAMPLE SIMPLIFIED BLOCK DIAGRAM OF THE ENHANCED PWM MODE
Duty Cycle Registers
DCxB<1:0>
CCPxM<3:0>
4
PxM<1:0>
2
CCPRxL
CCPx/PxA
CCPx/PxA
TRISx
CCPRxH (Slave)
PxB
Comparator
R
Q
Output
Controller
PxB
TRISx
PxC(2)
PxC
TMRx
Comparator
PRx
Note
(1)
TRISx
S
PxD
Clear Timer,
toggle PWM pin and
latch duty cycle
PxD(2)
TRISx
PWMxCON
1:
The 8-bit timer TMRx register is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler to create the 10-bit time
base.
2:
PxC and PxD are not available on Half-Bridge ECCP Modules.
DS41412C-page 188
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 14-12: EXAMPLE PIN ASSIGNMENTS FOR VARIOUS PWM ENHANCED MODES
ECCP Mode
PxM<1:0>
CCPx/PxA
Yes
PxC
(1)
Yes
PxD
(1)
Yes(1)
Single
00
Half-Bridge
10
Yes
Yes
No
No
Full-Bridge, Forward
01
Yes
Yes
Yes
Yes
Full-Bridge, Reverse
11
Yes
Yes
Yes
Yes
Note 1:
Yes
PxB
(1)
PWM Steering enables outputs in Single mode.
FIGURE 14-6:
EXAMPLE PWM (ENHANCED MODE) OUTPUT RELATIONSHIPS (ACTIVE-HIGH
STATE)
Signal
PxM<1:0>
PRX+1
Pulse
Width
0
Period
00
(Single Output)
PxA Modulated
Delay(1)
Delay(1)
PxA Modulated
10
(Half-Bridge)
PxB Modulated
PxA Active
01
(Full-Bridge,
Forward)
PxB Inactive
PxC Inactive
PxD Modulated
PxA Inactive
11
(Full-Bridge,
Reverse)
PxB Modulated
PxC Active
PxD Inactive
Relationships:
• Period = 4 * TOSC * (PRx + 1) * (TMRx Prescale Value)
• Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMRx Prescale Value)
• Delay = 4 * TOSC * (PWMxCON<6:0>)
Note 1: Dead-band delay is programmed using the PWMxCON register (Section 14.4.5 “Programmable Dead-Band Delay
Mode”).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 189
PIC18(L)F2X/4XK22
FIGURE 14-7:
EXAMPLE ENHANCED PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE)
Signal
PxM<1:0>
PRx+1
Pulse
Width
0
Period
00
(Single Output)
PxA Modulated
PxA Modulated
10
(Half-Bridge)
Delay(1)
Delay(1)
PxB Modulated
PxA Active
01
(Full-Bridge,
Forward)
PxB Inactive
PxC Inactive
PxD Modulated
PxA Inactive
11
(Full-Bridge,
Reverse)
PxB Modulated
PxC Active
PxD Inactive
Relationships:
• Period = 4 * TOSC * (PRx + 1) * (TMRx Prescale Value)
• Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMRx Prescale Value)
• Delay = 4 * TOSC * (PWMxCON<6:0>)
Note
1:
Dead-band delay is programmed using the PWMxCON register (Section 14.4.5 “Programmable Dead-Band Delay
Mode”).
DS41412C-page 190
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.4.1
HALF-BRIDGE MODE
In Half-Bridge mode, two pins are used as outputs to
drive push-pull loads. The PWM output signal is output
on the CCPx/PxA pin, while the complementary PWM
output signal is output on the PxB pin (see Figure 14-9).
This mode can be used for Half-Bridge applications, as
shown in Figure 14-9, or for Full-Bridge applications,
where four power switches are being modulated with
two PWM signals.
In Half-Bridge mode, the programmable dead-band delay
can be used to prevent shoot-through current in HalfBridge power devices. The value of the PDC<6:0> bits of
the PWMxCON register 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 14.4.5 “Programmable Dead-Band Delay
Mode” for more details of the dead-band delay
operations.
Since the PxA and PxB outputs are multiplexed with the
PORT data latches, the associated TRIS bits must be
cleared to configure PxA and PxB as outputs.
FIGURE 14-8:
Period
Period
Pulse Width
PxA(2)
td
td
PxB(2)
(1)
(1)
(1)
td = Dead-Band Delay
Note 1:
2:
FIGURE 14-9:
EXAMPLE OF HALFBRIDGE PWM OUTPUT
At this time, the TMRx register is equal to the
PRx register.
Output signals are shown as active-high.
EXAMPLE OF HALF-BRIDGE APPLICATIONS
Standard Half-Bridge Circuit (“Push-Pull”)
FET
Driver
+
PxA
Load
FET
Driver
+
PxB
-
Half-Bridge Output Driving a Full-Bridge Circuit
V+
FET
Driver
FET
Driver
PxA
FET
Driver
Load
FET
Driver
PxB
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 191
PIC18(L)F2X/4XK22
14.4.2
FULL-BRIDGE MODE
In Full-Bridge mode, all four pins are used as outputs.
An example of Full-Bridge application is shown in
Figure 14-10.
In the Forward mode, pin CCPx/PxA is driven to its active
state, pin PxD is modulated, while PxB and PxC will be
driven to their inactive state as shown in Figure 14-11.
In the Reverse mode, PxC is driven to its active state, pin
PxB is modulated, while PxA and PxD will be driven to
their inactive state as shown Figure 14-11.
PxA, PxB, PxC and PxD outputs are multiplexed with
the PORT data latches. The associated TRIS bits must
be cleared to configure the PxA, PxB, PxC and PxD
pins as outputs.
FIGURE 14-10:
EXAMPLE OF FULL-BRIDGE APPLICATION
V+
FET
Driver
QC
QA
FET
Driver
PxA
Load
PxB
FET
Driver
PxC
FET
Driver
QD
QB
VPxD
DS41412C-page 192
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 14-11:
EXAMPLE OF FULL-BRIDGE PWM OUTPUT
Forward Mode
Period
PxA
(2)
Pulse Width
PxB(2)
PxC(2)
PxD(2)
(1)
(1)
Reverse Mode
Period
Pulse Width
PxA(2)
PxB(2)
PxC(2)
PxD(2)
(1)
Note 1:
2:
(1)
At this time, the TMRx register is equal to the PRx register.
Output signal is shown as active-high.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 193
PIC18(L)F2X/4XK22
14.4.2.1
Direction Change in Full-Bridge
Mode
In the Full-Bridge mode, the PxM1 bit in the CCPxCON
register allows users to control the forward/reverse
direction. When the application firmware changes this
direction control bit, the module will change to the new
direction on the next PWM cycle.
A direction change is initiated in software by changing
the PxM1 bit of the CCPxCON register. The following
sequence occurs four Timer cycles prior to the end of
the current PWM period:
• The modulated outputs (PxB and PxD) are placed
in their inactive state.
• The associated unmodulated outputs (PxA and
PxC) are switched to drive in the opposite
direction.
• PWM modulation resumes at the beginning of the
next period.
See Figure 14-12 for an illustration of this sequence.
The Full-Bridge mode does not provide dead-band
delay. As one output is modulated at a time, dead-band
delay is generally not required. There is a situation
where dead-band delay is required. This situation
occurs when both of the following conditions are true:
1.
2.
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.
Figure 14-13 shows an example of the PWM direction
changing from forward to reverse, at a near 100% duty
cycle. In this example, at time t1, the output PxA and
PxD become inactive, while output PxC becomes
active. Since the turn off time of the power devices is
longer than the turn on time, a shoot-through current
will flow through power devices QC and QD (see
Figure 14-10) 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, two possible solutions for eliminating
the shoot-through current are:
1.
2.
Reduce PWM duty cycle for one 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.
FIGURE 14-12:
EXAMPLE OF PWM DIRECTION CHANGE
Period(1)
Signal
Period
PxA (Active-High)
PxB (Active-High)
Pulse Width
PxC (Active-High)
(2)
PxD (Active-High)
Pulse Width
Note 1:
2:
The direction bit PxM1 of the CCPxCON register is written any time during the PWM cycle.
When changing directions, the PxA and PxC signals switch before the end of the current PWM cycle. The
modulated PxB and PxD signals are inactive at this time. The length of this time is (TimerX Prescale)/FOSC,
where TimerX is Timer2, Timer4 or Timer6.
DS41412C-page 194
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 14-13:
EXAMPLE OF PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
Forward Period
t1
Reverse Period
PxA
PxB
PW
PxC
PxD
PW
TON
External Switch C
TOFF
External Switch D
Potential
Shoot-Through Current
Note 1:
14.4.3
T = TOFF – TON
All signals are shown as active-high.
2:
TON is the turn-on delay of power switch QC and its driver.
3:
TOFF is the turn-off delay of power switch QD and its driver.
ENHANCED PWM AUTOSHUTDOWN MODE
The PWM mode supports an Auto-Shutdown mode that
will disable the PWM outputs when an external
shutdown event occurs. Auto-Shutdown mode places
the PWM output pins into a predetermined state. This
mode is used to help prevent the PWM from damaging
the application.
The auto-shutdown sources are selected using the
CCPxAS<2:0> bits of the ECCPxAS register. A
shutdown event may be generated by:
• A logic ‘0’ on the INT pin
• Comparator Cx
• Setting the CCPxASE bit in firmware
of each pin pair is determined by the PSSxAC<1:0> and
PSSxBD<1:0> bits of the ECCPxAS register. Each pin
pair may be placed into one of three states:
• Drive logic ‘1’
• Drive logic ‘0’
• Tri-state (high-impedance)
Note 1: The auto-shutdown condition is a levelbased signal, not an edge-based signal.
As long as the level is present, the autoshutdown will persist.
2: Writing to the CCPxASE bit is disabled
while an auto-shutdown condition
persists.
A shutdown condition is indicated by the CCPxASE
(Auto-Shutdown Event Status) bit of the ECCPxAS
register. If the bit is a ‘0’, the PWM pins are operating
normally. If the bit is a ‘1’, the PWM outputs are in the
shutdown state.
3: Once the auto-shutdown condition has
been removed and the PWM restarted
(either through firmware or auto-restart),
the PWM signal will always restart at the
beginning of the next PWM period.
When a shutdown event occurs, two things happen:
The CCPxASE bit is set to ‘1’. The CCPxASE will
remain set until cleared in firmware or an auto-restart
occurs (see Section 14.4.4 “Auto-Restart Mode”).
The enabled PWM pins are asynchronously placed in
their shutdown states. The PWM output pins are
grouped into pairs [PxA/PxC] and [PxB/PxD]. The state
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 195
PIC18(L)F2X/4XK22
FIGURE 14-14:
PWM AUTO-SHUTDOWN WITH FIRMWARE RESTART (PXRSEN = 0)
Missing Pulse
(Auto-Shutdown)
Timer
Overflow
Timer
Overflow
Missing Pulse
(CCPxASE not clear)
Timer
Overflow
Timer
Overflow
Timer
Overflow
PWM Period
PWM Activity
Start of
PWM Period
Shutdown Event
CCPxASE bit
Shutdown
Event Occurs
14.4.4
AUTO-RESTART MODE
The Enhanced PWM can be configured to
automatically restart the PWM signal once the autoshutdown condition has been removed. Auto-restart is
enabled by setting the PxRSEN bit in the PWMxCON
register.
FIGURE 14-15:
Shutdown
Event Clears
PWM
Resumes
CCPxASE
Cleared by
Firmware
If auto-restart is enabled, the CCPxASE bit will remain
set as long as the auto-shutdown condition is active.
When the auto-shutdown condition is removed, the
CCPxASE bit will be cleared via hardware and normal
operation will resume.
PWM AUTO-SHUTDOWN WITH AUTO-RESTART (PXRSEN = 1)
Missing Pulse
(Auto-Shutdown)
Timer
Overflow
Timer
Overflow
Missing Pulse
(CCPxASE not clear)
Timer
Overflow
Timer
Overflow
Timer
Overflow
PWM Period
PWM Activity
Start of
PWM Period
Shutdown Event
CCPxASE bit
PWM
Resumes
Shutdown
Event Occurs
Shutdown
Event Clears
DS41412C-page 196
Preliminary
CCPxASE
Cleared by
Hardware
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.4.5
PROGRAMMABLE DEAD-BAND
DELAY MODE
FIGURE 14-16:
In Half-Bridge applications where all power switches
are modulated at the PWM frequency, 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) will 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.
Period
Period
Pulse Width
PxA(2)
td
td
PxB(2)
(1)
(1)
(1)
td = Dead-Band Delay
Note 1:
2:
In Half-Bridge mode, a digitally programmable deadband delay is available to avoid shoot-through current
from destroying the bridge power switches. The delay
occurs at the signal transition from the non-active state
to the active state. See Figure 14-16 for illustration.
The lower seven bits of the associated PWMxCON
register (Register 14-6) sets the delay period in terms
of microcontroller instruction cycles (TCY or 4 TOSC).
FIGURE 14-17:
EXAMPLE OF HALFBRIDGE PWM OUTPUT
At this time, the TMRx register is equal to the
PRx register.
Output signals are shown as active-high.
EXAMPLE OF HALF-BRIDGE APPLICATIONS
V+
Standard Half-Bridge Circuit (“Push-Pull”)
FET
Driver
+
V
-
PxA
Load
FET
Driver
+
V
-
PxB
V-
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 197
PIC18(L)F2X/4XK22
14.4.6
PWM STEERING MODE
FIGURE 14-18:
In Single Output mode, PWM steering allows any of the
PWM pins to be the modulated signal. Additionally, the
same PWM signal can be simultaneously available on
multiple pins.
STRxA
PxA Signal
CCPxM1
Once the Single Output mode is selected
(CCPxM<3:2> = 11 and PxM<1:0> = 00 of the
CCPxCON register), the user firmware can bring out
the same PWM signal to one, two, three or four output
pins by setting the appropriate Steering Enable bits
(STRxA, STRxB, STRxC and/or STRxD) of the
PSTRxCON register, as shown in Table 14-13.
PORT Data
CCPxM0
CCPxM1
While the PWM Steering mode is active, CCPxM<1:0>
bits of the CCPxCON register select the PWM output
polarity for the PxD, PxC, PxB and PxA pins.
The PWM auto-shutdown operation also applies to
PWM Steering mode as described in Section 14.4.3
“Enhanced PWM Auto-shutdown Mode”. An autoshutdown event will only affect pins that have PWM
outputs enabled.
0
PORT Data
0
PORT Data
PxB pin
TRIS
PxC pin
1
0
TRIS
STRxD
CCPxM0
TRIS
1
STRxC
The associated TRIS bits must be set to
output (‘0’) to enable the pin output driver
in order to see the PWM signal on the pin.
PxA pin
1
STRxB
PORT Data
Note:
SIMPLIFIED STEERING
BLOCK DIAGRAM
PxD pin
1
0
TRIS
Note 1:
Port outputs are configured as shown when
the CCPxCON register bits PxM<1:0> = 00
and CCPxM<3:2> = 11.
2:
Single PWM output requires setting at least
one of the STRx bits.
14.4.6.1
Steering Synchronization
The STRxSYNC bit of the PSTRxCON register gives
the user two selections of when the steering event will
happen. When the STRxSYNC bit is ‘0’, the steering
event will happen at the end of the instruction that
writes to the PSTRxCON register. In this case, the
output signal at the PxA, PxB, PxC and PxD pins may
be an incomplete PWM waveform. This operation is
useful when the user firmware needs to immediately
remove a PWM signal from the pin.
When the STRxSYNC bit is ‘1’, the effective steering
update will happen at the beginning of the next PWM
period. In this case, steering on/off the PWM output will
always produce a complete PWM waveform.
Figures 14-19 and 14-20 illustrate the timing diagrams
of the PWM steering depending on the STRxSYNC
setting.
DS41412C-page 198
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
14.4.7
START-UP CONSIDERATIONS
When any PWM mode is used, the application
hardware must use the proper external pull-up and/or
pull-down resistors on the PWM output pins.
The CCPxM<1:0> bits of the CCPxCON register allow
the user to choose whether the PWM output signals are
active-high or active-low for each pair of PWM output
pins (PxA/PxC and PxB/PxD). The PWM output
polarities must be selected before the PWM pin output
drivers are enabled. Changing the polarity
configuration while the PWM pin output drivers are
enable is not recommended since it may result in
damage to the application circuits.
modes must be enabled in the proper Output mode and
complete a full PWM cycle before enabling the PWM
pin output drivers. The completion of a full PWM cycle
is indicated by the TMRxIF bit of the PIR1, PIR2 or
PIR5 register being set as the second PWM period
begins.
Note:
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 PxA, PxB, PxC and PxD output latches may not be
in the proper states when the PWM module is
initialized. Enabling the PWM pin output drivers at the
same time as the Enhanced PWM modes may cause
damage to the application circuit. The Enhanced PWM
FIGURE 14-19:
EXAMPLE OF STEERING EVENT AT END OF INSTRUCTION (STRxSYNC = 0)
PWM Period
PWM
STRx
P1<D:A>
PORT Data
PORT Data
P1n = PWM
FIGURE 14-20:
EXAMPLE OF STEERING EVENT AT BEGINNING OF INSTRUCTION
(STRxSYNC = 1)
PWM
STRx
P1<D:A>
PORT Data
PORT Data
P1n = PWM
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 199
PIC18(L)F2X/4XK22
TABLE 14-13: REGISTERS ASSOCIATED WITH ENHANCED PWM
Name
ECCP1AS
Bit 7
CCP1ASE
CCP1CON
ECCP2AS
P1M<1:0>
CCPTMRS0
INTCON
Bit 4
Bit 3
DC1B<1:0>
P2M<1:0>
205
P2SSBD<1:0>
205
P3SSBD<1:0>
205
201
201
CCP3M<3:0>
C2TSEL<1:0>
—
Register
on Page
P1SSBD<1:0>
CCP2M<3:0>
P3SSAC<1:0>
DC3B<1:0>
—
Bit 0
CCP1M<3:0>
DC2B<1:0>
C3TSEL<1:0>
Bit 1
P2SSAC<1:0>
CCP3AS<2:0>
P3M<1:0>
Bit 2
P1SSAC<1:0>
CCP2AS<2:0>
CCP3ASE
CCP3CON
Bit 5
CCP1AS<2:0>
CCP2ASE
CCP2CON
ECCP3AS
Bit 6
201
C1TSEL<1:0>
204
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RCxIP
TXxIP
SSPIP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
130
PIE1
—
ADIE
RCxIE
TXxIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCLIE
HLVDIE
TMR3IE
CCP2IE
124
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
126
PIR1
—
ADIF
RCxIF
TXxIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCLIF
HLVDIF
TMR3IF
CCP2IF
119
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
121
PMD0
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
PR2
Timer2 Period Register
—
PR4
Timer4 Period Register
—
PR6
Timer6 Period Register
—
PSTR1CON
—
—
—
STR1SYNC
STR1D
STR1C
STR1B
STR1A
206
PSTR2CON
—
—
—
STR2SYNC
STR2D
STR2C
STR2B
STR2A
206
PSTR3CON
—
—
—
STR3SYNC
STR3D
STR3C
STR3B
STR3A
PWM1CON
P1RSEN
P1DC<6:0>
206
PWM2CON
P2RSEN
P2DC<6:0>
206
PWM3CON
P3RSEN
P3DC<6:0>
206
206
—
T2OUTPS<3:0>
TMR2ON
T2CKPS<1:0>
170
T4CON
—
T4OUTPS<3:0>
TMR4ON
T4CKPS<1:0>
170
T6CON
—
T6OUTPS<3:0>
TMR6ON
T6CKPS<1:0>
170
T2CON
TMR2
Timer2 Module Register
—
TMR4
Timer4 Module Register
—
TMR6
TRISA
Timer6 Module Register
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
—
TRISA2
TRISA1
TRISA0
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
—
TRISE2(1)
TRISE1(1)
TRISE0(1)
154
TRISE
WPUE3
—
—
—
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
Note 1:
These registers/bits are available on PIC18(L)F4XK22 devices.
DS41412C-page 200
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 14-14: CONFIGURATION REGISTERS ASSOCIATED WITH CAPTURE
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
354
Legend: — = Unimplemented location, read as ‘0’. Shaded bits are not used by Capture mode.
REGISTER 14-1:
CCPxCON: STANDARD CCPx CONTROL REGISTER
U-0
U-0
—
—
R/W-0
R/W-0
R/W-0
DCxB<1:0>
R/W-0
R/W-0
R/W-0
CCPxM<3:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Reset
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
Unused
bit 5-4
DCxB<1:0>: PWM Duty Cycle Least Significant bits
Capture mode:
Unused
Compare mode:
Unused
PWM mode:
These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPRxL.
bit 3-0
CCPxM<3:0>: ECCPx Mode Select bits
0000 = Capture/Compare/PWM off (resets the module)
0001 = Reserved
0010 = Compare mode: toggle output on match
0011 = Reserved
0100 =
0101 =
0110 =
0111 =
Capture mode: every falling edge
Capture mode: every rising edge
Capture mode: every 4th rising edge
Capture mode: every 16th rising edge
1000 = Compare mode: set output on compare match (CCPx pin is set, CCPxIF is set)
1001 = Compare mode: clear output on compare match (CCPx pin is cleared, CCPxIF is set)
1010 = Compare mode: generate software interrupt on compare match (CCPx pin is unaffected,
CCPxIF is set)
1011 = Compare mode: Special Event Trigger (CCPx pin is unaffected, CCPxIF is set)
TimerX (selected by CxTSEL bits) is reset
ADON is set, starting A/D conversion if A/D module is enabled(1)
11xx =: PWM mode
Note 1:
This feature is available on CCP5 only.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 201
PIC18(L)F2X/4XK22
REGISTER 14-2:
R/x-0
CCPxCON: ENHANCED CCPx CONTROL REGISTER
R/W-0
PxM<1:0>
R/W-0
R/W-0
R/W-0
DCxB<1:0>
R/W-0
R/W-0
R/W-0
CCPxM<3:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Reset
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
PxM<1:0>: Enhanced PWM Output Configuration bits
If CCPxM<3:2> = 00, 01, 10: (Capture/Compare modes)
xx = PxA assigned as Capture/Compare input; PxB, PxC, PxD assigned as port pins
Half-Bridge ECCP Modules(1):
If CCPxM<3:2> = 11: (PWM modes)
0x = Single output; PxA modulated; PxB assigned as port pin
1x = Half-Bridge output; PxA, PxB modulated with dead-band control
Full-Bridge ECCP Modules(1):
If CCPxM<3:2> = 11: (PWM modes)
00 = Single output; PxA modulated; PxB, PxC, PxD assigned as port pins
01 = Full-Bridge output forward; PxD modulated; PxA active; PxB, PxC inactive
10 = Half-Bridge output; PxA, PxB modulated with dead-band control; PxC, PxD assigned as port
pins
11 = Full-Bridge output reverse; PxB modulated; PxC active; PxA, PxD inactive
bit 5-4
Note 1:
DCxB<1:0>: PWM Duty Cycle Least Significant bits
Capture mode:
Unused
Compare mode:
Unused
PWM mode:
These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPRxL.
See Table 14-1 to determine Full-Bridge and Half-Bridge ECCPs for the device being used.
DS41412C-page 202
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 14-2:
bit 3-0
CCPxCON: ENHANCED CCPx CONTROL REGISTER (CONTINUED)
CCPxM<3:0>: ECCPx Mode Select bits
0000 = Capture/Compare/PWM off (resets the module)
0001 = Reserved
0010 = Compare mode: toggle output on match
0011 = Reserved
0100 =
0101 =
0110 =
0111 =
Capture mode: every falling edge
Capture mode: every rising edge
Capture mode: every 4th rising edge
Capture mode: every 16th rising edge
1000 = Compare mode: set output on compare match (CCPx pin is set, CCPxIF is set)
1001 = Compare mode: clear output on compare match (CCPx pin is cleared, CCPxIF is set)
1010 = Compare mode: generate software interrupt on compare match (CCPx pin is unaffected,
CCPxIF is set)
1011 = Compare mode: Special Event Trigger (CCPx pin is unaffected, CCPxIF is set)
TimerX is reset
Half-Bridge ECCP Modules(1):
1100 = PWM mode: PxA active-high; PxB active-high
1101 = PWM mode: PxA active-high; PxB active-low
1110 = PWM mode: PxA active-low; PxB active-high
1111 = PWM mode: PxA active-low; PxB active-low
Full-Bridge ECCP Modules(1):
1100 = PWM mode: PxA, PxC active-high; PxB, PxD active-high
1101 = PWM mode: PxA, PxC active-high; PxB, PxD active-low
1110 = PWM mode: PxA, PxC active-low; PxB, PxD active-high
1111 = PWM mode: PxA, PxC active-low; PxB, PxD active-low
Note 1:
See Table 14-1 to determine Full-Bridge and Half-Bridge ECCPs for the device being used.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 203
PIC18(L)F2X/4XK22
REGISTER 14-3:
R/W-0
CCPTMRS0: PWM TIMER SELECTION CONTROL REGISTER 0
R/W-0
U-0
R/W-0
—
C3TSEL<1:0>
R/W-0
C2TSEL<1:0>
U-0
R/W-0
—
R/W-0
C1TSEL<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
C3TSEL<1:0>: CCP3 Timer Selection bits
00 = CCP3 – Capture/Compare modes use Timer1, PWM modes use Timer2
01 = CCP3 – Capture/Compare modes use Timer3, PWM modes use Timer4
10 = CCP3 – Capture/Compare modes use Timer5, PWM modes use Timer6
11 = Reserved
bit 5
Unused
bit 4-3
C2TSEL<1:0>: CCP2 Timer Selection bits
00 = CCP2 – Capture/Compare modes use Timer1, PWM modes use Timer2
01 = CCP2 – Capture/Compare modes use Timer3, PWM modes use Timer4
10 = CCP2 – Capture/Compare modes use Timer5, PWM modes use Timer6
11 = Reserved
bit 2
Unused
bit 1-0
C1TSEL<1:0>: CCP1 Timer Selection bits
00 = CCP1 – Capture/Compare modes use Timer1, PWM modes use Timer2
01 = CCP1 – Capture/Compare modes use Timer3, PWM modes use Timer4
10 = CCP1 – Capture/Compare modes use Timer5, PWM modes use Timer6
11 = Reserved
REGISTER 14-4:
CCPTMRS1: PWM TIMER SELECTION CONTROL REGISTER 1
U-0
U-0
U-0
U-0
—
—
—
—
R/W-0
R/W-0
R/W-0
C5TSEL<1:0>
R/W-0
C4TSEL<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-4
Unimplemented: Read as ‘0’
bit 3-2
C5TSEL<1:0>: CCP5 Timer Selection bits
00 = CCP5 – Capture/Compare modes use Timer1, PWM modes use Timer2
01 = CCP5 – Capture/Compare modes use Timer3, PWM modes use Timer4
10 = CCP5 – Capture/Compare modes use Timer5, PWM modes use Timer6
11 = Reserved
bit 1-0
C4TSEL<1:0>: CCP4 Timer Selection bits
00 = CCP4 – Capture/Compare modes use Timer1, PWM modes use Timer2
01 = CCP4 – Capture/Compare modes use Timer3, PWM modes use Timer4
10 = CCP4 – Capture/Compare modes use Timer5, PWM modes use Timer6
11 = Reserved
DS41412C-page 204
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 14-5:
R/W-0
ECCPxAS: CCPX AUTO-SHUTDOWN CONTROL REGISTER
R/W-0
CCPxASE
R/W-0
R/W-0
CCPxAS<2:0>
R/W-0
R/W-0
R/W-0
PSSxAC<1:0>
R/W-0
PSSxBD<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
CCPxASE: CCPx Auto-shutdown Event Status bit
if PxRSEN = 1;
1 = An Auto-shutdown event occurred; CCPxASE bit will automatically clear when event goes away;
CCPx outputs in shutdown state
0 = CCPx outputs are operating
if PxRSEN = 0;
1 = An Auto-shutdown event occurred; bit must be cleared in software to restart PWM;
CCPx outputs in shutdown state
0 = CCPx outputs are operating
bit 6-4
CCxPAS<2:0>: CCPx Auto-Shutdown Source Select bits (1)
000 = Auto-shutdown is disabled
001 = Comparator C1 – output high will cause shutdown event
010 = Comparator C2 – output high will cause shutdown event
011 = Either Comparator C1 or C2 – output high will cause shutdown event
100 = FLT0 pin - low level will cause shutdown event
101 = FLT0 pin or Comparator C1 – low level will cause shutdown event
110 = FLT0 pin or Comparator C2 – low level will cause shutdown event
111 = FLT0 pin or Comparators C1 or C2 – low level will cause shutdown event
bit 3-2
PSSxAC<1:0>: Pins PxA and PxC Shutdown State Control bits
00 = Drive pins PxA and PxC to ‘0’
01 = Drive pins PxA and PxC to ‘1’
1x = Pins PxA and PxC tri-state
bit 1-0
PSSxBD<1:0>: Pins PxB and PxD Shutdown State Control bits
00 = Drive pins PxB and PxD to ‘0’
01 = Drive pins PxB and PxD to ‘1’
1x = Pins PxB and PxD tri-state
Note 1:
If C1SYNC or C2SYNC bits in the CM2CON1 register are enabled, the shutdown will be delayed by
Timer1.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 205
PIC18(L)F2X/4XK22
REGISTER 14-6:
R/W-0
PWMxCON: ENHANCED PWM CONTROL REGISTER
R/W-0
R/W-0
R/W-0
PxRSEN
R/W-0
R/W-0
R/W-0
R/W-0
PxDC<6:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
PxRSEN: PWM Restart Enable bit
1 = Upon auto-shutdown, the CCPxASE bit clears automatically once the shutdown event goes
away; the PWM restarts automatically
0 = Upon auto-shutdown, CCPxASE must be cleared in software to restart the PWM
bit 6-0
PxDC<6:0>: PWM Delay Count bits
PxDCx = Number of FOSC/4 (4 * TOSC) cycles between the scheduled time when a PWM signal
should transition active and the actual time it transitions active
PSTRxCON: PWM STEERING CONTROL REGISTER(1)
REGISTER 14-7:
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
—
—
—
STRxSYNC
STRxD
STRxC
STRxB
STRxA
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-5
Unimplemented: Read as ‘0’
bit 4
STRxSYNC: Steering Sync bit
1 = Output steering update occurs on next PWM period
0 = Output steering update occurs at the beginning of the instruction cycle boundary
bit 3
STRxD: Steering Enable bit D
1 = PxD pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxD pin is assigned to port pin
bit 2
STRxC: Steering Enable bit C
1 = PxC pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxC pin is assigned to port pin
bit 1
STRxB: Steering Enable bit B
1 = PxB pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxB pin is assigned to port pin
bit 0
STRxA: Steering Enable bit A
1 = PxA pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = PxA pin is assigned to port pin
Note 1:
The PWM Steering mode is available only when the CCPxCON register bits CCPxM<3:2> = 11 and
PxM<1:0> = 00.
DS41412C-page 206
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.0
15.1
MASTER SYNCHRONOUS
SERIAL PORT (MSSP1 AND
MSSP2) MODULE
The SPI interface supports the following modes and
features:
•
•
•
•
•
Master SSPx (MSSPx) Module
Overview
The Master Synchronous Serial Port (MSSPx) 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 MSSPx
module can operate in one of two modes:
Master mode
Slave mode
Clock Parity
Slave Select Synchronization (Slave mode only)
Daisy chain connection of slave devices
Figure 15-1 is a block diagram of the SPI interface
module.
• Serial Peripheral Interface (SPI)
• Inter-Integrated Circuit (I2C™)
FIGURE 15-1:
MSSPx BLOCK DIAGRAM (SPI MODE)
Data Bus
Read
Write
SSPxBUF Reg
SDIx
SSPxSR Reg
SDOx
bit 0
SSx
SSx Control
Enable
Shift
Clock
2 (CKP, CKE)
Clock Select
Edge
Select
SSPxM<3:0>
4
SCKx
Edge
Select
TRIS bit
 2010 Microchip Technology Inc.
Preliminary
( TMR22Output )
Prescaler TOSC
4, 16, 64
Baud Rate
Generator
(SSPxADD)
DS41412C-page 207
PIC18(L)F2X/4XK22
The I2C interface supports the following modes and
features:
Master mode
Slave mode
Byte NACKing (Slave mode)
Limited Multi-master support
7-bit and 10-bit addressing
Start and Stop interrupts
Interrupt masking
Clock stretching
Bus collision detection
General call address matching
Address masking
Address Hold and Data Hold modes
Selectable SDAx hold times
Note 1: In devices with more than one MSSP
module, it is very important to pay close
attention to SSPxCONx register names.
SSP1CON1 and SSP1CON2 registers
control different operational aspects of the
same module, while SSP1CON1 and
SSP2CON1 control the same features for
two different modules.
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, module I/O
signals, and bit names may use the
generic designator ‘x’ to indicate the use
of a numeral to distinguish a particular
module when required.
Figure 15-2 is a block diagram of the I2C interface
module in Master mode. Figure 15-3 is a diagram of the
I2C interface module in Slave mode.
MSSPx BLOCK DIAGRAM (I2C™ MASTER MODE)
Internal
Data Bus
Read
[SSPxM 3:0]
Write
SSPxBUF
Baud Rate
Generator
(SSPxADD)
SDAx
Shift
Clock
SDAx in
Receive Enable (RCEN)
SCLx
SCLx in
Bus Collision
DS41412C-page 208
LSb
Start bit, Stop bit,
Acknowledge
Generate (SSPxCON2)
Start bit Detect,
Stop bit Detect
Write Collision Detect
Clock Arbitration
State Counter for
end of XMIT/RCV
Address Match Detect
Preliminary
Clock Cntl
SSPxSR
MSb
(Hold off clock source)
FIGURE 15-2:
Clock Arbitrate/BCOL Detect
•
•
•
•
•
•
•
•
•
•
•
•
•
The PIC18(L)F2X/4XK22 has two MSSP modules,
MSSP1 and MSSP2, each module operating independently from the other.
Set/Reset: S, P, SSPxSTAT, WCOL, SSPxOV
Reset SEN, PEN (SSPxCON2)
Set SSPxIF, BCLxIF
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 15-3:
MSSPx BLOCK DIAGRAM (I2C™ SLAVE MODE)
Internal
Data Bus
Read
Write
SSPxBUF Reg
SCLx
Shift
Clock
SSPxSR Reg
SDAx
MSb
LSb
SSPxMSK Reg
Match Detect
Addr Match
SSPxADD Reg
Start and
Stop bit Detect
 2010 Microchip Technology Inc.
Preliminary
Set, Reset
S, P bits
(SSPxSTAT Reg)
DS41412C-page 209
PIC18(L)F2X/4XK22
15.2
SPI Mode Overview
The Serial Peripheral Interface (SPI) bus is a
synchronous serial data communication bus that
operates in Full-Duplex mode. Devices communicate
in a master/slave environment where the master device
initiates the communication. A slave device is
controlled through a chip select known as Slave Select.
The SPI bus specifies four signal connections:
•
•
•
•
During each SPI clock cycle, a full-duplex data
transmission occurs. This means that at the same time,
the slave device is sending out the MSb from its shift
register and the master device is reading this bit from
that same line and saving it as the LSb of its shift
register.
After 8 bits have been shifted out, the master and slave
have exchanged register values.
If there is more data to exchange, the shift registers are
loaded with new data and the process repeats itself.
Serial Clock (SCKx)
Serial Data Out (SDOx)
Serial Data In (SDIx)
Slave Select (SSx)
Whether the data is meaningful or not (dummy data),
depends on the application software. This leads to
three scenarios for data transmission:
Figure 15-1 shows the block diagram of the MSSPx
module when operating in SPI Mode.
The SPI bus operates with a single master device and
one or more slave devices. When multiple slave
devices are used, an independent Slave Select
connection is required from the master device to each
slave device.
Figure 15-4 shows a typical connection between a
master device and multiple slave devices.
The master selects only one slave at a time. Most slave
devices have tri-state outputs so their output signal
appears disconnected from the bus when they are not
selected.
Transmissions involve two shift registers, eight bits in
size, one in the master and one in the slave. With either
the master or the slave device, data is always shifted
out one bit at a time, with the Most Significant bit (MSb)
shifted out first. At the same time, a new Least
Significant bit (LSb) is shifted into the same register.
• Master sends useful data and slave sends dummy
data.
• Master sends useful data and slave sends useful
data.
• Master sends dummy data and slave sends useful
data.
Transmissions may involve any number of clock
cycles. When there is no more data to be transmitted,
the master stops sending the clock signal and it
deselects the slave.
Every slave device connected to the bus that has not
been selected through its slave select line must disregard the clock and transmission signals and must not
transmit out any data of its own.
Figure 15-5 shows a typical connection between two
processors configured as master and slave devices.
Data is shifted out of both shift registers on the
programmed clock edge and latched on the opposite
edge of the clock.
The master device transmits information out on its
SDOx output pin which is connected to, and received
by, the slave’s SDIx input pin. The slave device transmits information out on its SDOx output pin, which is
connected to, and received by, the master’s SDIx input
pin.
To begin communication, the master device first sends
out the clock signal. Both the master and the slave
devices should be configured for the same clock
polarity.
The master device starts a transmission by sending out
the MSb from its shift register. The slave device reads
this bit from that same line and saves it into the LSb
position of its shift register.
DS41412C-page 210
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 15-4:
SPI MASTER AND MULTIPLE SLAVE CONNECTION
SPI Master
SCLK
SCLK
SDOx
SDIx
SDIx
SDOx
General I/O
General I/O
SSx
General I/O
SCLK
SDIx
SDOx
SPI Slave
#1
SPI Slave
#2
SSx
SCLK
SDIx
SDOx
SPI Slave
#3
SSx
15.2.1
SPI MODE REGISTERS
15.2.2
The MSSPx module has five registers for SPI mode
operation. These are:
•
•
•
•
•
•
MSSPx STATUS register (SSPxSTAT)
MSSPx Control register 1 (SSPxCON1)
MSSPx Control register 3 (SSPxCON3)
MSSPx Data Buffer register (SSPxBUF)
MSSPx Address register (SSPxADD)
MSSPx Shift register (SSPxSR)
(Not directly accessible)
SSPxCON1 and SSPxSTAT are the control
STATUS registers in SPI mode operation.
SSPxCON1 register is readable and writable.
lower 6 bits of the SSPxSTAT are read-only.
upper two bits of the SSPxSTAT are read/write.
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:
•
•
•
•
and
The
The
The
In one SPI Master mode, SSPxADD can be loaded
with a value used in the Baud Rate Generator. More
information on the Baud Rate Generator is available in
Section 15.7 “Baud Rate Generator”.
SSPxSR is the shift register used for shifting data in
and out. SSPxBUF provides indirect access to the
SSPxSR register. SSPxBUF is the buffer register to
which data bytes are written, and from which data
bytes are read.
In receive operations, SSPxSR and SSPxBUF
together create a buffered receiver. When SSPxSR
receives a complete byte, it is transferred to SSPxBUF
and the SSPxIF interrupt is set.
During transmission, the SSPxBUF is not buffered. A
write to SSPxBUF will write to both SSPxBUF and
SSPxSR.
 2010 Microchip Technology Inc.
SPI MODE OPERATION
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)
To enable the serial port, SSPx Enable bit, SSPxEN of
the SSPxCON1 register, must be set. To reset or
reconfigure SPI mode, clear the SSPxEN bit, re-initialize the SSPxCONx registers and then set the SSPxEN
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 must have corresponding TRIS bit set
• SDOx must have corresponding TRIS bit cleared
• SCKx (Master mode) must have corresponding
TRIS bit cleared
• SCKx (Slave mode) must have corresponding
TRIS bit set
• SSx must have corresponding TRIS bit set
Preliminary
DS41412C-page 211
PIC18(L)F2X/4XK22
Any serial port function that is not desired may be
overridden by programming the corresponding data
direction (TRIS) register to the opposite value.
set. User software must clear the WCOL bit to allow the
following write(s) to the SSPxBUF register to complete
successfully.
The MSSPx 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 of the SSPxSTAT register, 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 SSPxBUF register during transmission/
reception of data will be ignored and the write collision
detect bit, WCOL of the SSPxCON1 register, will be
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 of the SSPxSTAT register,
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 MSSPx interrupt is used to determine when the
transmission/reception has completed. 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.
FIGURE 15-5:
SPI MASTER/SLAVE CONNECTION
SPI Master SSPxM<3:0> = 00xx
= 1010
SDOx
SPI Slave SSPxM<3:0> = 010x
SDIx
Serial Input Buffer
(BUF)
SDIx
Shift Register
(SSPxSR)
MSb
Serial Input Buffer
(SSPxBUF)
LSb
SCKx
General I/O
Processor 1
DS41412C-page 212
SDOx
Serial Clock
Slave Select
(optional)
Preliminary
Shift Register
(SSPxSR)
MSb
LSb
SCKx
SSx
Processor 2
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.2.3
SPI MASTER MODE
The master can initiate the data transfer at any time
because it controls the SCKx line. The master
determines when the slave (Processor 2, Figure 15-5)
is to 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).
The clock polarity is selected by appropriately
programming the CKP bit of the SSPxCON1 register
and the CKE bit of the SSPxSTAT register. This then,
would give waveforms for SPI communication as
shown in Figure 15-6, Figure 15-8 and Figure 15-9,
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
FOSC/(4 * (SSPxADD + 1))
Figure 15-6 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.
FIGURE 15-6:
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 0
bit 7
Input
Sample
(SMP = 1)
SSPxIF
SSPxSR to
SSPxBUF
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 213
PIC18(L)F2X/4XK22
15.2.4
15.2.5
SPI SLAVE MODE
In Slave mode, the data is transmitted and received as
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 of the SSPxCON1 register.
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. The shift register is clocked from the SCKx pin
input and when a byte is received, the device will generate an interrupt. If enabled, the device will wake-up
from Sleep.
15.2.4.1
Daisy-Chain Configuration
The SPI bus can sometimes be connected in a daisychain configuration. The first slave output is connected
to the second slave input, the second slave output is
connected to the third slave input, and so on. The final
slave output is connected to the master input. Each
slave sends out, during a second group of clock
pulses, an exact copy of what was received during the
first group of clock pulses. The whole chain acts as
one large communication shift register. The daisychain feature only requires a single Slave Select line
from the master device.
Figure 15-7 shows the block diagram of a typical
daisy-chain connection when operating in SPI Mode.
In a daisy-chain configuration, only the most recent
byte on the bus is required by the slave. Setting the
BOEN bit of the SSPxCON3 register will enable writes
to the SSPxBUF register, even if the previous byte has
not been read. This allows the software to ignore data
that may not apply to it.
SLAVE SELECT
SYNCHRONIZATION
The Slave Select can also be used to synchronize
communication. The Slave Select line is held high until
the master device is ready to communicate. When the
Slave Select line is pulled low, the slave knows that a
new transmission is starting.
If the slave fails to receive the communication properly,
it will be reset at the end of the transmission, when the
Slave Select line returns to a high state. The slave is
then ready to receive a new transmission when the
Slave Select line is pulled low again. If the Slave Select
line is not used, there is a risk that the slave will eventually become out of sync with the master. If the slave
misses a bit, it will always be one bit off in future transmissions. Use of the Slave Select line allows the slave
and master to align themselves at the beginning of
each transmission.
The SSx pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with SSx pin control
enabled (SSPxCON1<3:0> = 0100).
When the SSx pin is low, transmission and reception
are enabled and the 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: When the SPI is used in Slave mode with
CKE set; the user must enable SSx pin
control.
3: While operated in SPI Slave mode the
SMP bit of the SSPxSTAT register must
remain clear.
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 SSPxEN bit.
DS41412C-page 214
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 15-7:
SPI DAISY-CHAIN CONNECTION
SPI Master
SCLK
SCLK
SDOx
SDIx
SDIx
SDOx
General I/O
SPI Slave
#1
SSx
SCLK
SDIx
SDOx
SPI Slave
#2
SSx
SCLK
SDIx
SDOx
SPI Slave
#3
SSx
FIGURE 15-8:
SLAVE SELECT SYNCHRONOUS WAVEFORM
SSx
SCKx
(CKP = 0
CKE = 0)
SCKx
(CKP = 1
CKE = 0)
Write to
SSPxBUF
Shift register SSPxSR
and bit count are reset
SSPxBUF to
SSPxSR
SDOx
bit 7
bit 6
bit 7
SDIx
bit 6
bit 0
bit 0
bit 7
bit 7
Input
Sample
SSPxIF
Interrupt
Flag
SSPxSR to
SSPxBUF
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 215
PIC18(L)F2X/4XK22
FIGURE 15-9:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
SSx
Optional
SCKx
(CKP = 0
CKE = 0)
SCKx
(CKP = 1
CKE = 0)
Write to
SSPxBUF
Valid
SDOx
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDIx
bit 0
bit 7
Input
Sample
SSPxIF
Interrupt
Flag
SSPxSR to
SSPxBUF
Write Collision
detection active
FIGURE 15-10:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SSx
Not Optional
SCKx
(CKP = 0
CKE = 1)
SCKx
(CKP = 1
CKE = 1)
Write to
SSPxBUF
Valid
SDOx
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDIx
bit 0
bit 7
Input
Sample
SSPxIF
Interrupt
Flag
SSPxSR to
SSPxBUF
Write Collision
detection active
DS41412C-page 216
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.2.6
SPI OPERATION IN SLEEP MODE
In SPI Master mode, when the Sleep mode is selected,
all module clocks are halted and the transmission/
reception will remain in that state until the device
wakes. After the device returns to Run mode, the
module will resume transmitting and receiving data.
In SPI Master mode, module clocks may be operating
at a different speed than when in Full-Power mode; in
the case of the Sleep mode, all clocks are halted.
Special care must be taken by the user when the
MSSPx clock is much faster than the system clock.
In SPI Slave mode, the SPI Transmit/Receive Shift
register operates asynchronously to the device. This
allows the device to be placed in Sleep mode and data
to be shifted into the SPI Transmit/Receive Shift
register. When all 8 bits have been received, the
MSSPx interrupt flag bit will be set and if enabled, will
wake the device.
In Slave mode, when MSSPx interrupts are enabled,
after the master completes sending data, an MSSPx
interrupt will wake the controller from Sleep.
If an exit from Sleep mode is not desired, MSSPx
interrupts should be disabled.
TABLE 15-1:
Name
ANSELA
REGISTERS ASSOCIATED WITH SPI OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
152
ANSB4
ANSB3(1)
ANSB2(1)
ANSB1(1)
ANSB0(1)
153
ANSELB
—
—
ANSB5
ANSELC
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
153
ANSELD
ANSD7
ANSD6
ANSD5
ANSD4(2)
ANSD3(2)
ANSD2
ANSD1(2)
ANSD0(2)
153
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
PIR3
PMD1
MSSP2MD MSSP1MD
SSP1BUF
SSP1 Receive Buffer/Transmit Register
—
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
SSP1CON3
ACKTIM
PCIE
SCIE
BOEN
SDAHT
SBCDE
AHEN
DHEN
259
SSP1STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
255
SSP2BUF
SSPM<3:0>
256
SSP2 Receive Buffer/Transmit Register
—
SSP2CON1
WCOL
SSPOV
SSPEN
CKP
SSP2CON3
ACKTIM
PCIE
SCIE
BOEN
SDAHT
SBCDE
AHEN
DHEN
259
SSP2STAT
SMP
CKE
D/A
P
S
R/W
UA
BF
255
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3(1)
TRISB2(1)
TRISB1(1)
TRISB0(1)
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD
TRISD7
TRISD6
TRISD5
Legend:
Note 1:
2:
SSPM<3:0>
TRISD4(2) TRISD3(2)
TRISD2
256
TRISD1(2) TRISD0(2)
154
Shaded bits are not used by the MSSPx in SPI mode.
PIC18(L)F2XK22 devices.
PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 217
PIC18(L)F2X/4XK22
15.3
I2C MODE OVERVIEW
FIGURE 15-11:
The Inter-Integrated Circuit Bus (I2C) is a multi-master
serial data communication bus. Devices communicate
in a master/slave environment where the master
devices initiate the communication. A slave device is
controlled through addressing.
VDD
SCLK
The I2C bus specifies two signal connections:
• Serial Clock (SCLx)
• Serial Data (SDAx)
Figure 15-11 shows a typical connection between two
processors configured as master and slave devices.
The I2C bus can operate with one or more master
devices and one or more slave devices.
There are four potential modes of operation for a given
device:
• Master Transmit mode
(master is transmitting data to a slave)
• Master Receive mode
(master is receiving data from a slave)
• Slave Transmit mode
(slave is transmitting data to a master)
• Slave Receive mode
(slave is receiving data from the master)
SDOx
The Acknowledge bit (ACK) is an active-low signal,
which holds the SDAx line low to indicate to the
transmitter that the slave device has received the
transmitted data and is ready to receive more.
The transition of data bits is always performed while the
SCLx line is held low. Transitions that occur while the
SCLx line is held high are used to indicate Start and
Stop bits.
If the master intends to write to the slave, then it
repeatedly sends out a byte of data, with the slave
responding after each byte with an ACK bit. In this
example, the master device is in Master Transmit mode
and the slave is in Slave Receive mode.
If the master intends to read from the slave, then it
repeatedly receives a byte of data from the slave, and
responds after each byte with an ACK bit. In this
example, the master device is in Master Receive mode
and the slave is Slave Transmit mode.
To begin communication, a master device starts out in
Master Transmit mode. The master device sends out a
Start bit followed by the address byte of the slave it
intends to communicate with. This is followed by a single Read/Write bit, which determines whether the master intends to transmit to or receive data from the slave
device.
If the requested slave exists on the bus, it will respond
with an Acknowledge bit, otherwise known as an ACK.
The master then continues in either Transmit mode or
Receive mode and the slave continues in the complement, either in Receive mode or Transmit mode,
respectively.
A Start bit is indicated by a high-to-low transition of the
SDAx line while the SCLx line is held high. Address and
data bytes are sent out, Most Significant bit (MSb) first.
The Read/Write bit is sent out as a logical one when the
master intends to read data from the slave, and is sent
out as a logical zero when it intends to write data to the
slave.
DS41412C-page 218
Slave
SDIx
Figure 15-11 shows the block diagram of the MSSPx
module when operating in I2C mode.
SCLK
VDD
Master
Both the SCLx and SDAx connections are bidirectional
open-drain lines, each requiring pull-up resistors for the
supply voltage. Pulling the line to ground is considered
a logical zero and letting the line float is considered a
logical one.
I2C™ MASTER/
SLAVE CONNECTION
On the last byte of data communicated, the master
device may end the transmission by sending a Stop bit.
If the master device is in Receive mode, it sends the
Stop bit in place of the last ACK bit. A Stop bit is
indicated by a low-to-high transition of the SDAx line
while the SCLx line is held high.
In some cases, the master may want to maintain control of the bus and re-initiate another transmission. If
so, the master device may send another Start bit in
place of the Stop bit or last ACK bit when it is in receive
mode.
The I2C bus specifies three message protocols;
• Single message where a master writes data to a
slave.
• Single message where a master reads data from
a slave.
• Combined message where a master initiates a
minimum of two writes, or two reads, or a
combination of writes and reads, to one or more
slaves.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
When one device is transmitting a logical one, or letting
the line float, and a second device is transmitting a
logical zero, or holding the line low, the first device can
detect that the line is not a logical one. This detection,
when used on the SCLx line, is called clock stretching.
Clock stretching give slave devices a mechanism to
control the flow of data. When this detection is used on
the SDAx line, it is called arbitration. Arbitration
ensures that there is only one master device
communicating at any single time.
15.3.1
CLOCK STRETCHING
When a slave device has not completed processing
data, it can delay the transfer of more data through the
process of clock stretching. An addressed slave device
may hold the SCLx clock line low after receiving or
sending a bit, indicating that it is not yet ready to
continue. The master that is communicating with the
slave will attempt to raise the SCLx line in order to
transfer the next bit, but will detect that the clock line
has not yet been released. Because the SCLx
connection is open-drain, the slave has the ability to
hold that line low until it is ready to continue
communicating.
Clock stretching allows receivers that cannot keep up
with a transmitter to control the flow of incoming data.
15.3.2
ARBITRATION
Each master device must monitor the bus for Start and
Stop bits. If the device detects that the bus is busy, it
cannot begin a new message until the bus returns to an
Idle state.
However, two master devices may try to initiate a
transmission on or about the same time. When this
occurs, the process of arbitration begins. Each
transmitter checks the level of the SDAx data line and
compares it to the level that it expects to find. The first
transmitter to observe that the two levels don’t match,
loses arbitration, and must stop transmitting on the
SDAx line.
For example, if one transmitter holds the SDAx line to
a logical one (lets it float) and a second transmitter
holds it to a logical zero (pulls it low), the result is that
the SDAx line will be low. The first transmitter then
observes that the level of the line is different than
expected and concludes that another transmitter is
communicating.
The first transmitter to notice this difference is the one
that loses arbitration and must stop driving the SDAx
line. If this transmitter is also a master device, it also
must stop driving the SCLx line. It then can monitor the
lines for a Stop condition before trying to reissue its
transmission. In the meantime, the other device that
has not noticed any difference between the expected
and actual levels on the SDAx line continues with its
original transmission. It can do so without any complications, because so far, the transmission appears
exactly as expected with no other transmitter disturbing
the message.
Slave Transmit mode can also be arbitrated, when a
master addresses multiple slaves, but this is less
common.
If two master devices are sending a message to two
different slave devices at the address stage, the master
sending the lower slave address always wins
arbitration. When two master devices send messages
to the same slave address, and addresses can
sometimes refer to multiple slaves, the arbitration
process must continue into the data stage.
Arbitration usually occurs very rarely, but it is a
necessary process for proper multi-master support.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 219
PIC18(L)F2X/4XK22
15.4
I2C MODE OPERATION
TABLE 15-2:
All MSSPx I2C communication is byte oriented and
shifted out MSb first. Six SFR registers and 2 interrupt
flags interface the module with the PIC® microcontroller and user software. Two pins, SDAx and SCLx,
are exercised by the module to communicate with
other external I2C devices.
15.4.1
BYTE FORMAT
All communication in I2C is done in 9-bit segments. A
byte is sent from a master to a slave or vice-versa,
followed by an Acknowledge bit sent back. After the
8th falling edge of the SCLx line, the device outputting
data on the SDAx changes that pin to an input and
reads in an acknowledge value on the next clock
pulse.
The clock signal, SCLx, is provided by the master.
Data is valid to change while the SCLx signal is low,
and sampled on the rising edge of the clock. Changes
on the SDAx line while the SCLx line is high define
special conditions on the bus, explained below.
15.4.2
DEFINITION OF I2C TERMINOLOGY
There is language and terminology in the description
of I2C communication that have definitions specific to
I2C. That word usage is defined below and may be
used in the rest of this document without explanation. This table was adapted from the Phillips I2C
specification.
15.4.3
SDAx AND SCLx PINS
Selection of any I2C mode with the SSPxEN bit set,
forces the SCLx and SDAx pins to be open-drain.
These pins should be set by the user to inputs by
setting the appropriate TRIS bits.
Note: Data is tied to output zero when an I2C mode
is enabled.
15.4.4
SDAx HOLD TIME
The hold time of the SDAx pin is selected by the
SDAHT bit of the SSPxCON3 register. Hold time is the
time SDAx is held valid after the falling edge of SCLx.
Setting the SDAHT bit selects a longer 300 ns minimum hold time and may help on buses with large
capacitance.
DS41412C-page 220
TERM
I2C™ BUS TERMS
Description
Transmitter
The device which shifts data out
onto the bus.
Receiver
The device which shifts data in
from the bus.
Master
The device that initiates a transfer,
generates clock signals and terminates a transfer.
Slave
The device addressed by the master.
Multi-master
A bus with more than one device
that can initiate data transfers.
Arbitration
Procedure to ensure that only one
master at a time controls the bus.
Winning arbitration ensures that
the message is not corrupted.
Synchronization Procedure to synchronize the
clocks of two or more devices on
the bus.
Idle
No master is controlling the bus,
and both SDAx and SCLx lines are
high.
Active
Any time one or more master
devices are controlling the bus.
Slave device that has received a
Addressed
Slave
matching address and is actively
being clocked by a master.
Matching
Address byte that is clocked into a
Address
slave that matches the value
stored in SSPxADD.
Write Request
Slave receives a matching
address with R/W bit clear, and is
ready to clock in data.
Read Request
Master sends an address byte with
the R/W bit set, indicating that it
wishes to clock data out of the
Slave. This data is the next and all
following bytes until a Restart or
Stop.
Clock Stretching When a device on the bus holds
SCLx low to stall communication.
Bus Collision
Any time the SDAx line is sampled
low by the module while it is outputting and expected high state.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.4.5
15.4.7
START CONDITION
The I2C specification defines a Start condition as a
transition of SDAx from a high-to -low state while SCLx
line is high. A Start condition is always generated by
the master and signifies the transition of the bus from
an Idle to an active state. Figure 15-10 shows wave
forms for Start and Stop conditions.
A Restart is valid any time that a Stop would be valid.
A master can issue a Restart if it wishes to hold the
bus after terminating the current transfer. A Restart
has the same effect on the slave that a Start would,
resetting all slave logic and preparing it to clock in an
address. The master may want to address the same or
another slave.
A bus collision can occur on a Start condition if the
module samples the SDAx line low before asserting it
low. This does not conform to the I2C specification that
states no bus collision can occur on a Start.
15.4.6
RESTART CONDITION
In 10-bit Addressing Slave mode a Restart is required
for the master to clock data out of the addressed slave.
Once a slave has been fully addressed, matching both
high and low address bytes, the master can issue a
Restart and the high address byte with the R/W bit set.
The slave logic will then hold the clock and prepare to
clock out data.
STOP CONDITION
A Stop condition is a transition of the SDAx line from a
low-to-high state while the SCLx line is high.
After a full match with R/W clear in 10-bit mode, a prior
match flag is set and maintained. Until a Stop
condition, a high address with R/W clear, or high
address match fails.
Note: At least one SCLx low time must appear
before a Stop is valid, therefore, if the SDAx
line goes low then high again while the SCLx
line stays high, only the Start condition is
detected.
15.4.8
START/STOP CONDITION INTERRUPT
MASKING
The SCIE and PCIE bits of the SSPxCON3 register
can enable the generation of an interrupt in Slave
modes that do not typically support this function. Slave
modes where interrupt on Start and Stop detect are
already enabled, these bits will have no effect.
FIGURE 15-12:
I2C™ START AND STOP CONDITIONS
SDAx
SCLx
S
Start
P
Change of
Change of
Data Allowed
Data Allowed
Condition
FIGURE 15-13:
Stop
Condition
I2C™ RESTART CONDITION
Sr
Change of
Change of
Data Allowed
Restart
Data Allowed
Condition
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 221
PIC18(L)F2X/4XK22
15.4.9
15.5
ACKNOWLEDGE SEQUENCE
The 9th SCLx pulse for any transferred byte in I2C is
dedicated as an Acknowledge. It allows receiving
devices to respond back to the transmitter by pulling
the SDAx line low. The transmitter must release control of the line during this time to shift in the response.
The Acknowledge (ACK) is an active-low signal, pulling the SDAx line low indicated to the transmitter that
the device has received the transmitted data and is
ready to receive more.
The result of an ACK is placed in the ACKSTAT bit of
the SSPxCON2 register.
Slave software, when the AHEN and DHEN bits are
set, allow the user to set the ACK value sent back to
the transmitter. The ACKDT bit of the SSPxCON2
register is set/cleared to determine the response.
Slave hardware will generate an ACK response if the
AHEN and DHEN bits of the SSPxCON3 register are
clear.
There are certain conditions where an ACK will not be
sent by the slave. If the BF bit of the SSPxSTAT
register or the SSPxOV bit of the SSPxCON1 register
are set when a byte is received.
When the module is addressed, after the 8th falling
edge of SCLx on the bus, the ACKTIM bit of the
SSPxCON3 register is set. The ACKTIM bit indicates
the acknowledge time of the active bus.
The ACKTIM Status bit is only active when the AHEN
bit or DHEN bit is enabled.
I2C SLAVE MODE OPERATION
The MSSPx Slave mode operates in one of four
modes selected in the SSPxM bits of SSPxCON1
register. The modes can be divided into 7-bit and 10-bit
Addressing mode. 10-bit Addressing modes operate
the same as 7-bit with some additional overhead for
handling the larger addresses.
Modes with Start and Stop bit interrupts operated the
same as the other modes with SSPxIF additionally
getting set upon detection of a Start, Restart, or Stop
condition.
15.5.1
SLAVE MODE ADDRESSES
The SSPxADD register (Register 15-6) contains the
Slave mode address. The first byte received after a
Start or Restart condition is compared against the
value stored in this register. If the byte matches, the
value is loaded into the SSPxBUF register and an
interrupt is generated. If the value does not match, the
module goes Idle and no indication is given to the
software that anything happened.
The SSPx Mask register (Register 15-5) affects the
address matching process. See Section 15.5.9
“SSPx Mask Register” for more information.
15.5.1.1
I2C Slave 7-bit Addressing Mode
In 7-bit Addressing mode, the LSb of the received data
byte is ignored when determining if there is an address
match.
15.5.1.2
I2C Slave 10-bit Addressing Mode
In 10-bit Addressing mode, the first received byte is
compared to the binary value of ‘1 1 1 1 0 A9 A8 0’. A9
and A8 are the two MSb of the 10-bit address and
stored in bits 2 and 1 of the SSPxADD register.
After the acknowledge of the high byte the UA bit is set
and SCLx is held low until the user updates SSPxADD
with the low address. The low address byte is clocked
in and all 8 bits are compared to the low address value
in SSPxADD. Even if there is not an address match;
SSPxIF and UA are set, and SCLx is held low until
SSPxADD is updated to receive a high byte again.
When SSPxADD is updated the UA bit is cleared. This
ensures the module is ready to receive the high
address byte on the next communication.
A high and low address match as a write request is
required at the start of all 10-bit addressing
communication. A transmission can be initiated by
issuing a Restart once the slave is addressed, and
clocking in the high address with the R/W bit set. The
slave hardware will then acknowledge the read
request and prepare to clock out data. This is only
valid for a slave after it has received a complete high
and low address byte match.
DS41412C-page 222
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.5.2
SLAVE RECEPTION
15.5.2.2
When the R/W bit of a matching received address byte
is clear, the R/W bit of the SSPxSTAT register is
cleared. The received address is loaded into the
SSPxBUF register and acknowledged.
When the overflow condition exists for a received
address, then not Acknowledge is given. An overflow
condition is defined as either bit BF of the SSPxSTAT
register is set, or bit SSPxOV of the SSPxCON1 register is set. The BOEN bit of the SSPxCON3 register
modifies this operation. For more information see
Register 15-4.
An MSSPx interrupt is generated for each transferred
data byte. Flag bit, SSPxIF, must be cleared by
software.
When the SEN bit of the SSPxCON2 register is set,
SCLx will be held low (clock stretch) following each
received byte. The clock must be released by setting
the CKP bit of the SSPxCON1 register, except
sometimes in 10-bit mode. See Section 15.2.3 “SPI
Master Mode” for more detail.
15.5.2.1
7-bit Addressing Reception
This section describes a standard sequence of events
for the MSSPx module configured as an I2C slave in
7-bit Addressing mode. All decisions made by hardware or software and their effect on reception.
Figure 15-13 and Figure 15-14 is used as a visual
reference for this description.
This is a step by step process of what typically must
be done to accomplish I2C communication.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Start bit detected.
S bit of SSPxSTAT is set; SSPxIF is set if
interrupt on Start detect is enabled.
Matching address with R/W bit clear is received.
The slave pulls SDAx low sending an ACK to the
master, and sets SSPxIF bit.
Software clears the SSPxIF bit.
Software reads received address from
SSPxBUF clearing the BF flag.
If SEN = 1; Slave software sets CKP bit to
release the SCLx line.
The master clocks out a data byte.
Slave drives SDAx low sending an ACK to the
master, and sets SSPxIF bit.
Software clears SSPxIF.
Software reads the received byte from
SSPxBUF clearing BF.
Steps 8-12 are repeated for all received bytes
from the master.
Master sends Stop condition, setting P bit of
SSPxSTAT, and the bus goes Idle.
 2010 Microchip Technology Inc.
7-bit Reception with AHEN and DHEN
Slave device reception with AHEN and DHEN set
operate the same as without these options with extra
interrupts and clock stretching added after the 8th falling edge of SCLx. These additional interrupts allow the
slave software to decide whether it wants to ACK the
receive address or data byte, rather than the hardware. This functionality adds support for PMBus™ that
was not present on previous versions of this module.
This list describes the steps that need to be taken by
slave software to use these options for I2C
communication. Figure 15-15 displays a module using
both address and data holding. Figure 15-16 includes
the operation with the SEN bit of the SSPxCON2
register set.
1.
S bit of SSPxSTAT is set; SSPxIF is set if
interrupt on Start detect is enabled.
2. Matching address with R/W bit clear is clocked
in. SSPxIF is set and CKP cleared after the 8th
falling edge of SCLx.
3. Slave clears the SSPxIF.
4. Slave can look at the ACKTIM bit of the
SSPxCON3 register to determine if the SSPxIF
was after or before the ACK.
5. Slave reads the address value from SSPxBUF,
clearing the BF flag.
6. Slave sets ACK value clocked out to the master
by setting ACKDT.
7. Slave releases the clock by setting CKP.
8. SSPxIF is set after an ACK, not after a NACK.
9. If SEN = 1 the slave hardware will stretch the
clock after the ACK.
10. Slave clears SSPxIF.
Note: SSPxIF is still set after the 9th falling edge of
SCLx even if there is no clock stretching and
BF has been cleared. Only if NACK is sent to
master is SSPxIF not set.
11. SSPxIF set and CKP cleared after 8th falling
edge of SCLx for a received data byte.
12. Slave looks at ACKTIM bit of SSPxCON3 to
determine the source of the interrupt.
13. Slave reads the received data from SSPxBUF
clearing BF.
14. Steps 7-14 are the same for each received data
byte.
15. Communication is ended by either the slave
sending an ACK = 1, or the master sending a
Stop condition. If a Stop is sent and Interrupt on
Stop detect is disabled, the slave will only know
by polling the P bit of the SSTSTAT register.
Preliminary
DS41412C-page 223
DS41412C-page 224
Preliminary
SSPxOV
BF
SSPxIF
S
1
A7
2
A6
3
A5
4
A4
5
A3
6
A2
7
A1
8
9
ACK
1
D7
2
D6
4
D4
5
D3
6
D2
7
D1
SSPxBUF is read
Cleared by software
3
D5
Receiving Data
8
9
2
D6
First byte
of data is
available
in SSPxBUF
1
D0 ACK D7
4
D4
5
D3
6
D2
7
D1
8
D0
SSPxOV set because
SSPxBUF is still full.
ACK is not sent.
Cleared by software
3
D5
Receiving Data
From Slave to Master
9
P
SSPxIF set on 9th
falling edge of
SCLx
ACK = 1
FIGURE 15-14:
SCLx
SDAx
Receiving Address
Bus Master sends
Stop condition
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, RECEPTION (SEN = 0, AHEN = 0, DHEN = 0)
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
CKP
SSPxOV
BF
SSPxIF
1
SCLx
S
A7
2
A6
3
A5
4
A4
5
A3
6
A2
7
A1
8
9
R/W=0 ACK
SEN
2
D6
3
D5
4
D4
5
D3
6
D2
7
D1
8
D0
CKP is written to ‘1’ in software,
releasing SCLx
SSPxBUF is read
Cleared by software
Clock is held low until CKP is set to ‘1’
1
D7
Receive Data
9
ACK
SEN
3
D5
4
D4
5
D3
First byte
of data is
available
in SSPxBUF
6
D2
7
D1
SSPxOV set because
SSPxBUF is still full.
ACK is not sent.
Cleared by software
2
D6
CKP is written to 1 in software,
releasing SCLx
1
D7
Receive Data
8
D0
9
ACK
SCLx is not held
low because
ACK= 1
SSPxIF set on 9th
falling edge of SCLx
P
FIGURE 15-15:
SDAx
Receive Address
Bus Master sends
Stop condition
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, RECEPTION (SEN = 1, AHEN = 0, DHEN = 0)
DS41412C-page 225
DS41412C-page 226
Preliminary
P
S
ACKTIM
CKP
ACKDT
BF
SSPxIF
S
Receiving Address
1
3
5
6
7
8
ACK the received
byte
Slave software
clears ACKDT to
Address is
read from
SSBUF
If AHEN = 1:
SSPxIF is set
4
ACKTIM set by hardware
on 8th falling edge of SCLx
When AHEN=1:
CKP is cleared by hardware
and SCLx is stretched
2
A7 A6 A5 A4 A3 A2 A1
Receiving Data
9
2
3
4
5
6
7
ACKTIM cleared by
hardware in 9th
rising edge of SCLx
When DHEN=1:
CKP is cleared by
hardware on 8th falling
edge of SCLx
SSPxIF is set on
9th falling edge of
SCLx, after ACK
1
8
ACK D7 D6 D5 D4 D3 D2 D1 D0
Received Data
1
2
4
5
6
ACKTIM set by hardware
on 8th falling edge of SCLx
CKP set by software,
SCLx is released
8
Slave software
sets ACKDT to
not ACK
7
Cleared by software
3
D7 D6 D5 D4 D3 D2 D1 D0
Data is read from SSPxBUF
9
ACK
9
P
No interrupt
after not ACK
from Slave
ACK=1
Master sends
Stop condition
FIGURE 15-16:
SCLx
SDAx
Master Releases SDAx
to slave for ACK sequence
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, RECEPTION (SEN = 0, AHEN = 1, DHEN = 1)
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
P
S
ACKTIM
CKP
ACKDT
BF
SSPxIF
S
Receiving Address
4
5
6 7
8
When AHEN = 1;
on the 8th falling edge
of SCLx of an address
byte, CKP is cleared
Slave software clears
ACKDT to ACK
the received byte
Received
address is loaded into
SSPxBUF
2 3
ACKTIM is set by hardware
on 8th falling edge of SCLx
1
A7 A6 A5 A4 A3 A2 A1
9
ACK
Receive Data
2 3
4
5
6 7
8
ACKTIM is cleared by hardware
on 9th rising edge of SCLx
When DHEN = 1;
on the 8th falling edge
of SCLx of a received
data byte, CKP is cleared
Received data is
available on SSPxBUF
Cleared by software
1
D7 D6 D5 D4 D3 D2 D1 D0
9
ACK
Receive Data
1
3 4
5
6 7
8
Set by software,
release SCLx
Slave sends
not ACK
SSPxBUF can be
read any time before
next byte is loaded
2
D7 D6 D5 D4 D3 D2 D1 D0
9
ACK
CKP is not cleared
if not ACK
No interrupt after
if not ACK
from Slave
P
Master sends
Stop condition
FIGURE 15-17:
SCLx
SDAx
R/W = 0
Master releases
SDAx to slave for ACK sequence
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, RECEPTION (SEN = 1, AHEN = 1, DHEN = 1)
DS41412C-page 227
PIC18(L)F2X/4XK22
15.5.3
SLAVE TRANSMISSION
15.5.3.2
7-bit 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, and an ACK pulse is
sent by the slave on the ninth bit.
A master device can transmit a read request to a
slave, and then clock data out of the slave. The list
below outlines what software for a slave will need to do
to accomplish a standard transmission. Figure 15-17
can be used as a reference to this list.
Following the ACK, slave hardware clears the CKP bit
and the SCLx pin is held low (see Section 15.5.6
“Clock Stretching” for more detail). By stretching the
clock, the master will be unable to assert another clock
pulse until the slave is done preparing the transmit
data.
1.
The transmit data must be loaded into the SSPxBUF
register which also loads the SSPxSR register. Then
the SCLx pin should be released by setting the CKP bit
of the SSPxCON1 register. 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.
The ACK pulse from the master-receiver is latched on
the rising edge of the ninth SCLx input pulse. This ACK
value is copied to the ACKSTAT bit of the SSPxCON2
register. If ACKSTAT is set (not ACK), then the data
transfer is complete. In this case, when the not ACK is
latched by the slave, the slave goes Idle and waits 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, the SCLx pin must be
released by setting bit CKP.
An MSSPx interrupt is generated for each data transfer
byte. The SSPxIF bit must be cleared by 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.
15.5.3.1
Slave Mode Bus Collision
A slave receives a Read request and begins shifting
data out on the SDAx line. If a bus collision is detected
and the SBCDE bit of the SSPxCON3 register is set,
the BCLxIF bit of the PIRx register is set. Once a bus
collision is detected, the slave goes Idle and waits to be
addressed again. User software can use the BCLxIF bit
to handle a slave bus collision.
DS41412C-page 228
Master sends a Start condition on SDAx and
SCLx.
2. S bit of SSPxSTAT is set; SSPxIF is set if interrupt on Start detect is enabled.
3. Matching address with R/W bit set is received by
the slave setting SSPxIF bit.
4. Slave hardware generates an ACK and sets
SSPxIF.
5. SSPxIF bit is cleared by user.
6. Software reads the received address from
SSPxBUF, clearing BF.
7. R/W is set so CKP was automatically cleared
after the ACK.
8. The slave software loads the transmit data into
SSPxBUF.
9. CKP bit is set releasing SCLx, allowing the master to clock the data out of the slave.
10. SSPxIF is set after the ACK response from the
master is loaded into the ACKSTAT register.
11. SSPxIF bit is cleared.
12. The slave software checks the ACKSTAT bit to
see if the master wants to clock out more data.
Note 1: If the master ACKs the clock will be
stretched.
2: ACKSTAT is the only bit updated on the
rising edge of SCLx (9th) rather than the
falling.
13. Steps 9-13 are repeated for each transmitted
byte.
14. If the master sends a not ACK; the clock is not
held, but SSPxIF is still set.
15. The master sends a Restart condition or a Stop.
16. The slave is no longer addressed.
Preliminary
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
P
S
D/A
R/W
ACKSTAT
CKP
BF
SSPxIF
S
Receiving Address
1
2
5
6
7
8
Indicates an address
has been received
R/W is copied from the
matching address byte
9
R/W = 1 Automatic
ACK
Received address
is read from SSPxBUF
4
When R/W is set
SCLx is always
held low after 9th SCLx
falling edge
3
A7 A6 A5 A4 A3 A2 A1
Transmitting Data
Automatic
2
3
4
5
Set by software
Data to transmit is
loaded into SSPxBUF
Cleared by software
1
6
7
8
9
D7 D6 D5 D4 D3 D2 D1 D0 ACK
Transmitting Data
2
3
4
5
7
8
CKP is not
held for not
ACK
6
Masters not ACK
is copied to
ACKSTAT
BF is automatically
cleared after 8th falling
edge of SCLx
1
D7 D6 D5 D4 D3 D2 D1 D0
9
ACK
P
FIGURE 15-18:
SCLx
SDAx
Master sends
Stop condition
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, TRANSMISSION (AHEN = 0)
DS41412C-page 229
PIC18(L)F2X/4XK22
15.5.3.3
7-bit Transmission with Address
Hold Enabled
Setting the AHEN bit of the SSPxCON3 register
enables additional clock stretching and interrupt
generation after the 8th falling edge of a received
matching address. Once a matching address has
been clocked in, CKP is cleared and the SSPxIF
interrupt is set.
Figure 15-18 displays a standard waveform of a 7-bit
Address Slave Transmission with AHEN enabled.
1.
2.
Bus starts Idle.
Master sends Start condition; the S bit of
SSPxSTAT is set; SSPxIF is set if interrupt on
Start detect is enabled.
3. Master sends matching address with R/W bit
set. After the 8th falling edge of the SCLx line the
CKP bit is cleared and SSPxIF interrupt is
generated.
4. Slave software clears SSPxIF.
5. Slave software reads ACKTIM bit of SSPxCON3
register, and R/W and D/A of the SSPxSTAT
register to determine the source of the interrupt.
6. Slave reads the address value from the SSPxBUF
register clearing the BF bit.
7. Slave software decides from this information if it
wishes to ACK or not ACK and sets ACKDT bit
of the SSPxCON2 register accordingly.
8. Slave sets the CKP bit releasing SCLx.
9. Master clocks in the ACK value from the slave.
10. Slave hardware automatically clears the CKP bit
and sets SSPxIF after the ACK if the R/W bit is
set.
11. Slave software clears SSPxIF.
12. Slave loads value to transmit to the master into
SSPxBUF setting the BF bit.
Note: SSPxBUF cannot be loaded until after the
ACK.
13. Slave sets CKP bit releasing the clock.
14. Master clocks out the data from the slave and
sends an ACK value on the 9th SCLx pulse.
15. Slave hardware copies the ACK value into the
ACKSTAT bit of the SSPxCON2 register.
16. Steps 10-15 are repeated for each byte
transmitted to the master from the slave.
17. If the master sends a not ACK the slave
releases the bus allowing the master to send a
Stop and end the communication.
Note: Master must send a not ACK on the last byte
to ensure that the slave releases the SCLx
line to receive a Stop.
DS41412C-page 230
Preliminary
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
D/A
R/W
ACKTIM
CKP
ACKSTAT
ACKDT
BF
SSPxIF
S
Receiving Address
2
4
5
6
7
8
Slave clears
ACKDT to ACK
address
ACKTIM is set on 8th falling
edge of SCLx
9
ACK
When R/W = 1;
CKP is always
cleared after ACK
R/W = 1
Received address
is read from SSPxBUF
3
When AHEN = 1;
CKP is cleared by hardware
after receiving matching
address.
1
A7 A6 A5 A4 A3 A2 A1
3
4
5
6
Cleared by software
2
Set by software,
releases SCLx
Data to transmit is
loaded into SSPxBUF
1
7
8
9
Transmitting Data
Automatic
D7 D6 D5 D4 D3 D2 D1 D0 ACK
ACKTIM is cleared
on 9th rising edge of SCLx
Automatic
Transmitting Data
1
3
4
5
6
7
after not ACK
CKP not cleared
Master’s ACK
response is copied
to SSPxSTAT
BF is automatically
cleared after 8th falling
edge of SCLx
2
8
D7 D6 D5 D4 D3 D2 D1 D0
9
ACK
P
Master sends
Stop condition
FIGURE 15-19:
SCLx
SDAx
Master releases SDAx
to slave for ACK sequence
PIC18(L)F2X/4XK22
I2C SLAVE, 7-BIT ADDRESS, TRANSMISSION (AHEN = 1)
DS41412C-page 231
PIC18(L)F2X/4XK22
15.5.4
SLAVE MODE 10-BIT ADDRESS
RECEPTION
15.5.5
This section describes a standard sequence of events
for the MSSPx module configured as an I2C slave in
10-bit Addressing mode.
Figure 15-19 and is used as a visual reference for this
description.
This is a step by step process of what must be done by
slave software to accomplish I2C communication.
1.
2.
3.
4.
5.
6.
7.
8.
Bus starts Idle.
Master sends Start condition; S bit of SSPxSTAT
is set; SSPxIF is set if interrupt on Start detect is
enabled.
Master sends matching high address with R/W
bit clear; UA bit of the SSPxSTAT register is set.
Slave sends ACK and SSPxIF is set.
Software clears the SSPxIF bit.
Software reads received address from SSPxBUF
clearing the BF flag.
Slave loads low address into SSPxADD,
releasing SCLx.
Master sends matching low address byte to the
slave; UA bit is set.
10-BIT ADDRESSING WITH ADDRESS OR
DATA HOLD
Reception using 10-bit addressing with AHEN or
DHEN set is the same as with 7-bit modes. The only
difference is the need to update the SSPxADD register
using the UA bit. All functionality, specifically when the
CKP bit is cleared and SCLx line is held low are the
same. Figure 15-20 can be used as a reference of a
slave in 10-bit addressing with AHEN set.
Figure 15-21 shows a standard waveform for a slave
transmitter in 10-bit Addressing mode.
Note: Updates to the SSPxADD register are not
allowed until after the ACK sequence.
9.
Slave sends ACK and SSPxIF is set.
Note: If the low address does not match, SSPxIF
and UA are still set so that the slave software
can set SSPxADD back to the high address.
BF is not set because there is no match.
CKP is unaffected.
10. Slave clears SSPxIF.
11. Slave reads the received matching address
from SSPxBUF clearing BF.
12. Slave loads high address into SSPxADD.
13. Master clocks a data byte to the slave and clocks
out the slaves ACK on the 9th SCLx pulse;
SSPxIF is set.
14. If SEN bit of SSPxCON2 is set, CKP is cleared
by hardware and the clock is stretched.
15. Slave clears SSPxIF.
16. Slave reads the received byte from SSPxBUF
clearing BF.
17. If SEN is set the slave sets CKP to release the
SCLx.
18. Steps 13-17 repeat for each received byte.
19. Master sends Stop to end the transmission.
DS41412C-page 232
Preliminary
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
CKP
UA
BF
SSPxIF
S
1
1
2
1
5
6
7
0 A9 A8
8
Set by hardware
on 9th falling edge
4
1
When UA = 1;
SCLx is held low
9
ACK
If address matches
SSPxADD it is loaded into
SSPxBUF
3
1
Receive First Address Byte
1
3
4
5
6
7
8
Software updates SSPxADD
and releases SCLx
2
9
A7 A6 A5 A4 A3 A2 A1 A0 ACK
Receive Second Address Byte
1
3
4
5
6
7
8
9
1
3
4
5
6
7
Data is read
from SSPxBUF
SCLx is held low
while CKP = 0
2
8
9
D7 D6 D5 D4 D3 D2 D1 D0 ACK
Receive Data
Set by software,
When SEN = 1;
releasing SCLx
CKP is cleared after
9th falling edge of received byte
Receive address is
read from SSPxBUF
Cleared by software
2
D7 D6 D5 D4 D3 D2 D1 D0 ACK
Receive Data
P
FIGURE 15-20:
SCLx
SDAx
Master sends
Stop condition
PIC18(L)F2X/4XK22
I2C SLAVE, 10-BIT ADDRESS, RECEPTION (SEN = 1, AHEN = 0, DHEN = 0)
DS41412C-page 233
DS41412C-page 234
Preliminary
ACKTIM
CKP
UA
ACKDT
BF
2
1
5
0
6
A9
7
A8
Set by hardware
on 9th falling edge
4
1
ACKTIM is set by hardware
on 8th falling edge of SCLx
If when AHEN = 1;
on the 8th falling edge
of SCLx of an address
byte, CKP is cleared
Slave software clears
ACKDT to ACK
the received byte
3
1
8
R/W = 0
9
ACK
UA
2
A6
3
A5
4
A4
5
A3
6
A2
7
A1
Update to SSPxADD is
not allowed until 9th
falling edge of SCLx
SSPxBUF can be
read anytime before
the next received byte
Cleared by software
1
A7
Receive Second Address Byte
8
A0
9
ACK
UA
2
D6
3
D5
4
D4
6
D2
Set CKP with software
releases SCLx
7
D1
Update of SSPxADD,
clears UA and releases
SCLx
5
D3
Receive Data
Cleared by software
1
D7
8
9
2
Received data
is read from
SSPxBUF
1
D6 D5
Receive Data
D0 ACK D7
FIGURE 15-21:
SSPxIF
1
SCLx
S
1
SDAx
Receive First Address Byte
PIC18(L)F2X/4XK22
I2C SLAVE, 10-BIT ADDRESS, RECEPTION (SEN = 0, AHEN = 1, DHEN = 0)
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
Preliminary
D/A
R/W
ACKSTAT
CKP
UA
BF
SSPxIF
4
5
6
7
Set by hardware
3
Indicates an address
has been received
UA indicates SSPxADD
must be updated
SSPxBUF loaded
with received address
2
8
9
1
SCLx
S
Receiving Address R/W = 0
1 1 1 1 0 A9 A8
ACK
1
3
4
5
6
7 8
After SSPxADD is
updated, UA is cleared
and SCLx is released
Cleared by software
2
9
A7 A6 A5 A4 A3 A2 A1 A0 ACK
Receiving Second Address Byte
1
4
5
6
7 8
Set by hardware
2 3
R/W is copied from the
matching address byte
When R/W = 1;
CKP is cleared on
9th falling edge of SCLx
High address is loaded
back into SSPxADD
Received address is
read from SSPxBUF
Sr
1 1 1 1 0 A9 A8
Receive First Address Byte
9
ACK
2
3
4
5
6
7
8
Masters not ACK
is copied
Set by software
releases SCLx
Data to transmit is
loaded into SSPxBUF
1
D7 D6 D5 D4 D3 D2 D1 D0
Transmitting Data Byte
9
P
Master sends
Stop condition
ACK = 1
Master sends
not ACK
FIGURE 15-22:
SDAx
Master sends
Restart event
PIC18(L)F2X/4XK22
I2C SLAVE, 10-BIT ADDRESS, TRANSMISSION (SEN = 0, AHEN = 0, DHEN = 0)
DS41412C-page 235
PIC18(L)F2X/4XK22
15.5.6
CLOCK STRETCHING
15.5.6.2
Clock stretching occurs when a device on the bus
holds the SCLx line low effectively pausing communication. The slave may stretch the clock to allow more
time to handle data or prepare a response for the master device. A master device is not concerned with
stretching as anytime it is active on the bus and not
transferring data it is stretching. Any stretching done
by a slave is invisible to the master software and handled by the hardware that generates SCLx.
The CKP bit of the SSPxCON1 register is used to
control stretching in software. Any time the CKP bit is
cleared, the module will wait for the SCLx line to go
low and then hold it. Setting CKP will release SCLx
and allow more communication.
15.5.6.1
Normal Clock Stretching
Following an ACK if the R/W bit of SSPxSTAT is set, a
read request, the slave hardware will clear CKP. This
allows the slave time to update SSPxBUF with data to
transfer to the master. If the SEN bit of SSPxCON2 is
set, the slave hardware will always stretch the clock
after the ACK sequence. Once the slave is ready; CKP
is set by software and communication resumes.
Note 1: The BF bit has no effect on whether the
clock will be stretched or not. This is
different than previous versions of the
module that would not stretch the clock,
clear CKP, if SSPxBUF was read before
the 9th falling edge of SCLx.
2: Previous versions of the module did not
stretch the clock for a transmission if
SSPxBUF was loaded before the 9th falling edge of SCLx. It is now always cleared
for read requests.
FIGURE 15-23:
10-bit Addressing Mode
In 10-bit Addressing mode, when the UA bit is set, the
clock is always stretched. This is the only time the
SCLx is stretched without CKP being cleared. SCLx is
released immediately after a write to SSPxADD.
Note: Previous versions of the module did not
stretch the clock if the second address byte
did not match.
15.5.6.3
Byte NACKing
When the AHEN bit of SSPxCON3 is set; CKP is
cleared by hardware after the 8th falling edge of SCLx
for a received matching address byte. When the
DHEN bit of SSPxCON3 is set; CKP is cleared after
the 8th falling edge of SCLx for received data.
Stretching after the 8th falling edge of SCLx allows the
slave to look at the received address or data and
decide if it wants to ACK the received data.
15.5.7
CLOCK SYNCHRONIZATION AND
THE CKP BIT
Any time the CKP bit is cleared, the module will wait
for the SCLx line to go low and then hold it. 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 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 released SCLx. This ensures that a write
to the CKP bit will not violate the minimum high time
requirement for SCLx (see Figure 15-22).
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 ‚ – 1
DX
SCLx
CKP
Master device
asserts clock
Master device
releases clock
WR
SSPxCON1
DS41412C-page 236
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.5.8
GENERAL CALL ADDRESS SUPPORT
In 10-bit Address mode, the UA bit will not be set on
the reception of the general call address. The slave
will prepare to receive the second byte as data, just as
it would in 7-bit mode.
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 device. 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.
If the AHEN bit of the SSPxCON3 register is set, just
as with any other address reception, the slave
hardware will stretch the clock after the 8th falling
edge of SCLx. The slave must then set its ACKDT
value and release the clock with communication
progressing as it would normally.
The general call address is a reserved address in the
I2C protocol, defined as address 0x00. When the
GCEN bit of the SSPxCON2 register is set, the slave
module will automatically ACK the reception of this
address regardless of the value stored in SSPxADD.
After the slave clocks in an address of all zeros with the
R/W bit clear, an interrupt is generated and slave software can read SSPxBUF and respond. Figure 15-23
shows a general call reception sequence.
FIGURE 15-24:
SLAVE MODE GENERAL CALL ADDRESS SEQUENCE
Address is compared to General Call Address
after ACK, set interrupt
R/W = 0
ACK D7
General Call Address
SDAx
SCLx
S
1
2
3
4
5
6
7
8
9
1
Receiving Data
ACK
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
9
SSPxIF
BF (SSPxSTAT<0>)
Cleared by software
SSPxBUF is read
GCEN (SSPxCON2<7>)
’1’
15.5.9
SSPx MASK REGISTER
An SSPx Mask (SSPxMSK) register (Register 15-5) is
available in I2C Slave mode as a mask for the value
held in the SSPxSR register during an address
comparison operation. A zero (‘0’) bit in the SSPxMSK
register has the effect of making the corresponding bit
of the received address a “don’t care”.
This register is reset to all ‘1’s upon any Reset
condition and, therefore, has no effect on standard
SSPx operation until written with a mask value.
The SSPx Mask register is active during:
• 7-bit Address mode: address compare of A<7:1>.
• 10-bit Address mode: address compare of A<7:0>
only. The SSPx mask has no effect during the
reception of the first (high) byte of the address.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 237
PIC18(L)F2X/4XK22
15.6
I2C MASTER MODE
15.6.1
Master mode is enabled by setting and clearing the
appropriate SSPxM bits in the SSPxCON1 register and
by setting the SSPxEN bit. In Master mode, the SCLx
and SDAx lines are set as inputs and are manipulated
by the MSSPx 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 MSSPx module is disabled. Control of the I 2C bus may be taken when the P bit is set,
or the bus is Idle.
In Firmware Controlled Master mode, user code
conducts all I 2C bus operations based on Start and
Stop bit condition detection. Start and Stop condition
detection is the only active circuitry in this mode. All
other communication is done by the user software
directly manipulating the SDAx and SCLx lines.
The following events will cause the SSPx Interrupt Flag
bit, SSPxIF, to be set (SSPx interrupt, if enabled):
•
•
•
•
•
Start condition detected
Stop condition detected
Data transfer byte transmitted/received
Acknowledge transmitted/received
Repeated Start generated
Note 1: The MSSPx 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
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.
A Baud Rate Generator is used to set the clock
frequency output on SCLx. See Section 15.7 “Baud
Rate Generator” for more detail.
2: When in Master mode, Start/Stop
detection is masked and an interrupt is
generated when the SEN/PEN bit is
cleared and the generation is complete.
DS41412C-page 238
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.6.2
CLOCK ARBITRATION
Clock arbitration occurs when the master, during any
receive, transmit or Repeated Start/Stop condition,
releases 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
SCLx pin is sampled high, the Baud Rate Generator is
reloaded with the contents of SSPxADD<7:0> 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 15-25).
FIGURE 15-25:
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
SDAx
DX ‚ – 1
DX
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
15.6.3
WCOL STATUS FLAG
If the user writes the SSPxBUF when a Start, Restart,
Stop, Receive or Transmit sequence is in progress, the
WCOL is set and the contents of the buffer are
unchanged (the write does not occur). Any time the
WCOL bit is set it indicates that an action on SSPxBUF
was attempted while the module was not Idle.
Note:
Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPxCON2 is disabled until the Start
condition is complete.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 239
PIC18(L)F2X/4XK22
15.6.4
I2C MASTER MODE START
by hardware; the Baud Rate Generator is suspended,
leaving the SDAx line held low and the Start condition
is complete.
CONDITION TIMING
To initiate a Start condition, the user sets the Start
Enable bit, SEN, of the SSPxCON2 register. If the
SDAx and SCLx pins are sampled high, the Baud Rate
Generator is reloaded with the contents of
SSPxADD<7:0> 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
of the SSPxSTAT1 register to be set. Following this,
the Baud Rate Generator is reloaded with the contents
of SSPxADD<7:0> and resumes its count. When the
Baud Rate Generator times out (TBRG), the SEN bit of
the SSPxCON2 register will be automatically cleared
FIGURE 15-26:
Note 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.
2: The Philips I2C Specification states that a
bus collision cannot occur on a Start.
FIRST START BIT TIMING
Set S bit (SSPxSTAT<3>)
Write to SEN bit occurs here
At completion of Start bit,
hardware clears SEN bit
and sets SSPxIF bit
SDAx = 1,
SCLx = 1
TBRG
TBRG
Write to SSPxBUF occurs here
SDAx
1st bit
2nd bit
TBRG
SCLx
S
DS41412C-page 240
Preliminary
TBRG
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.6.5
I2C MASTER MODE REPEATED
SSPxCON2 register 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 of the
SSPxSTAT register will be set. The SSPxIF bit will not
be set until the Baud Rate Generator has timed out.
START CONDITION TIMING
A Repeated Start condition occurs when the RSEN bit
of the SSPxCON2 register is programmed high and the
master state machine is no longer active. 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 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 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. SCLx is
asserted low. Following this, the RSEN bit of the
FIGURE 15-27:
Note 1: If RSEN is programmed while any other
event is in progress, it will not take effect.
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’.
REPEAT START CONDITION WAVEFORM
S bit set by hardware
Write to SSPxCON2
occurs here
SDAx = 1,
SCLx (no change)
At completion of Start bit,
hardware clears RSEN bit
and sets SSPxIF
SDAx = 1,
SCLx = 1
TBRG
TBRG
TBRG
1st bit
SDAx
Write to SSPxBUF occurs here
TBRG
SCLx
Sr
TBRG
Repeated Start
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 241
PIC18(L)F2X/4XK22
15.6.6
I2C MASTER MODE TRANSMISSION
15.6.6.3
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. SCLx is held low for one Baud Rate Generator rollover count (TBRG). Data should be valid before
SCLx is released high. 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 ACKSTAT bit
on the rising 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 15-27).
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
release 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 of the
SSPxCON2 register. 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.
15.6.6.1
ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit of the SSPxCON2
register 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.
15.6.6.4
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
BF Status Flag
Typical Transmit Sequence:
The user generates a Start condition by setting
the SEN bit of the SSPxCON2 register.
SSPxIF is set by hardware on completion of the
Start.
SSPxIF is cleared by software.
The MSSPx module will wait the required start
time before any other operation takes place.
The user loads the SSPxBUF with the slave
address to transmit.
Address is shifted out the SDAx pin until all 8 bits
are transmitted. Transmission begins as soon
as SSPxBUF is written to.
The MSSPx module shifts in the ACK bit from
the slave device and writes its value into the
ACKSTAT bit of the SSPxCON2 register.
The MSSPx module generates an interrupt at
the end of the ninth clock cycle by setting the
SSPxIF bit.
The user loads the SSPxBUF with eight bits of
data.
Data is shifted out the SDAx pin until all 8 bits
are transmitted.
The MSSPx module shifts in the ACK bit from
the slave device and writes its value into the
ACKSTAT bit of the SSPxCON2 register.
Steps 8-11 are repeated for all transmitted data
bytes.
The user generates a Stop or Restart condition
by setting the PEN or RSEN bits of the
SSPxCON2 register. Interrupt is generated once
the Stop/Restart condition is complete.
In Transmit mode, the BF bit of the SSPxSTAT register
is set when the CPU writes to SSPxBUF and is cleared
when all 8 bits are shifted out.
15.6.6.2
WCOL Status Flag
If the user writes 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 does not occur).
WCOL must be cleared by software before the next
transmission.
DS41412C-page 242
Preliminary
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
S
Preliminary
R/W
PEN
SEN
BF (SSPxSTAT<0>)
SSPxIF
SCLx
SDAx
A6
A5
A4
A3
A2
A1
3
4
5
Cleared by 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 by software
Cleared by software service routine
from SSPx interrupt
2
D6
Transmitting Data or Second Half
of 10-bit Address
P
ACKSTAT in
SSPxCON2 = 1
Cleared by software
9
ACK
From slave, clear ACKSTAT bit SSPxCON2<6>
FIGURE 15-28:
SEN = 0
Write SSPxCON2<0> SEN = 1
Start condition begins
PIC18(L)F2X/4XK22
I2C MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS)
DS41412C-page 243
PIC18(L)F2X/4XK22
15.6.7
I2C MASTER MODE RECEPTION
15.6.7.4
Master mode reception is enabled by programming the
Receive Enable bit, RCEN, of the SSPxCON2 register.
Note:
The MSSPx 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 MSSPx 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, of
the SSPxCON2 register.
15.6.7.1
3.
4.
5.
6.
7.
8.
9.
10.
11.
SSPxOV Status Flag
In receive operation, the SSPxOV bit is set when 8 bits
are received into the SSPxSR and the BF flag bit is
already set from a previous reception.
15.6.7.3
2.
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.
15.6.7.2
1.
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 does not occur).
DS41412C-page 244
12.
13.
14.
15.
Preliminary
Typical Receive Sequence:
The user generates a Start condition by setting
the SEN bit of the SSPxCON2 register.
SSPxIF is set by hardware on completion of the
Start.
SSPxIF is cleared by software.
User writes SSPxBUF with the slave address to
transmit and the R/W bit set.
Address is shifted out the SDAx pin until all 8 bits
are transmitted. Transmission begins as soon
as SSPxBUF is written to.
The MSSPx module shifts in the ACK bit from
the slave device and writes its value into the
ACKSTAT bit of the SSPxCON2 register.
The MSSPx module generates an interrupt at
the end of the ninth clock cycle by setting the
SSPxIF bit.
User sets the RCEN bit of the SSPxCON2 register and the Master clocks in a byte from the slave.
After the 8th falling edge of SCLx, SSPxIF and
BF are set.
Master clears SSPxIF and reads the received
byte from SSPxUF, clears BF.
Master sets ACK value sent to slave in ACKDT
bit of the SSPxCON2 register and initiates the
ACK by setting the ACKEN bit.
Masters ACK is clocked out to the slave and
SSPxIF is set.
User clears SSPxIF.
Steps 8-13 are repeated for each received byte
from the slave.
Master sends a not ACK or Stop to end
communication.
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
S
Preliminary
RCEN
ACKEN
SSPxOV
BF
(SSPxSTAT<0>)
SDAx = 0, SCLx = 1
while CPU
responds to SSPxIF
SSPxIF
SCLx
SDAx
1
A7
2
4
5
6
Cleared by software
3
A6 A5 A4 A3 A2
Transmit Address to Slave
7
8
9
ACK
Receiving Data from Slave
2
3
5
6
7
8
D0
9
ACK
Receiving Data from Slave
2
3
4
RCEN cleared
automatically
5
6
7
Cleared by software
Set SSPxIF interrupt
at end of Acknowledge
sequence
Data shifted in on falling edge of CLK
1
ACK from Master
SDAx = ACKDT = 0
Cleared in
software
Set SSPxIF at end
of receive
9
ACK is not sent
ACK
RCEN cleared
automatically
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
SSPxOV is set because
SSPxBUF is still full
8
D0
RCEN cleared
automatically
Set ACKEN, start Acknowledge sequence
SDAx = ACKDT = 1
D7 D6 D5 D4 D3 D2 D1
Last bit is shifted into SSPxSR and
contents are unloaded into SSPxBUF
Cleared by software
Set SSPxIF interrupt
at end of receive
4
Cleared by software
1
D7 D6 D5 D4 D3 D2 D1
Master configured as a receiver
by programming SSPxCON2<3> (RCEN = 1)
A1 R/W
RCEN = 1, start
next receive
ACK from Master
SDAx = ACKDT = 0
FIGURE 15-29:
RCEN cleared
automatically
Master configured as a receiver
by programming SSPxCON2<3> (RCEN = 1)
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
PIC18(L)F2X/4XK22
I2C™ MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
DS41412C-page 245
PIC18(L)F2X/4XK22
15.6.8
ACKNOWLEDGE SEQUENCE
TIMING
15.6.9
A Stop bit is asserted on the SDAx pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit, PEN, of the SSPxCON2 register. 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 of the
SSPxSTAT register is set. A TBRG later, the PEN bit is
cleared and the SSPxIF bit is set (Figure 15-30).
An Acknowledge sequence is enabled by setting the
Acknowledge Sequence Enable bit, ACKEN, of the
SSPxCON2 register. 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 MSSPx module then goes into Idle mode
(Figure 15-29).
15.6.8.1
15.6.9.1
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 does
not 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 does
not occur).
FIGURE 15-30:
STOP CONDITION TIMING
ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here,
write to SSPxCON2
ACKEN = 1, ACKDT = 0
ACKEN automatically cleared
TBRG
TBRG
SDAx
SCLx
ACK
D0
8
9
SSPxIF
SSPxIF set at
the end of receive
Cleared in
software
Cleared in
software
SSPxIF set at the end
of Acknowledge sequence
Note: TBRG = one Baud Rate Generator period.
DS41412C-page 246
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 15-31:
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 setup Stop condition
Note: TBRG = one Baud Rate Generator period.
15.6.10
SLEEP OPERATION
15.6.12
the I2C slave
While in Sleep mode,
module can receive
addresses or data and when an address match or
complete byte transfer occurs, wake the processor
from Sleep (if the MSSPx interrupt is enabled).
15.6.11
EFFECTS OF A RESET
A Reset disables the MSSPx module and terminates
the current transfer.
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
MSSPx module is disabled. Control of the I 2C bus may
be taken when the P bit of the SSPxSTAT register is
set, or the bus is Idle, with both the S and P bits clear.
When the bus is busy, enabling the SSPx 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 by
hardware with the result placed in the BCLxIF bit.
The states where arbitration can be lost are:
•
•
•
•
•
 2010 Microchip Technology Inc.
Address Transfer
Data Transfer
A Start Condition
A Repeated Start Condition
An Acknowledge Condition
Preliminary
DS41412C-page 247
PIC18(L)F2X/4XK22
15.6.13
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
is ‘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 15-31).
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.
FIGURE 15-32:
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.
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 does not match what is driven
by the master.
Bus collision has occurred.
SDAx
SCLx
Set bus collision
interrupt (BCLxIF)
BCLxIF
DS41412C-page 248
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.6.13.1
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 15-32).
SCLx is sampled low before SDAx is asserted
low (Figure 15-33).
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 15-34). 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 zero; 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 MSSPx module is reset to its Idle state
(Figure 15-32).
The Start condition begins with the SDAx and SCLx
pins deasserted. When the SDAx pin is sampled high,
the Baud Rate Generator is loaded and counts down. 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 15-33:
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.
SSPx 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 by software
S
SSPxIF
SSPxIF and BCLxIF are
cleared by software
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 249
PIC18(L)F2X/4XK22
FIGURE 15-34:
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
by software
S
’0’
’0’
SSPxIF
’0’
’0’
FIGURE 15-35:
BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDAx = 0, SCLx = 1
Set S
Less than TBRG
SDAx
SCLx
TBRG
SDAx pulled low by other master.
Reset BRG and assert SDAx.
S
SCLx pulled low after BRG
time-out
SEN
BCLxIF
Set SSPxIF
Set SEN, enable Start
sequence if SDAx = 1, SCLx = 1
’0’
S
SSPxIF
SDAx = 0, SCLx = 1,
set SSPxIF
DS41412C-page 250
Preliminary
Interrupts cleared
by software
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
15.6.13.2
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’, Figure 15-35).
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 15-36.
When the user releases SDAx and the pin is allowed to
float high, the BRG is loaded with SSPxADD and
counts down to zero. The SCLx pin is then deasserted
and when sampled high, the SDAx pin is sampled.
FIGURE 15-36:
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 by software
S
’0’
SSPxIF
’0’
FIGURE 15-37:
BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG
TBRG
SDAx
SCLx
BCLxIF
SCLx goes low before SDAx,
set BCLxIF. Release SDAx and SCLx.
Interrupt cleared
by software
RSEN
’0’
S
SSPxIF
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 251
PIC18(L)F2X/4XK22
15.6.13.3
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 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 15-37). 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 15-38).
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 15-38:
BUS COLLISION DURING A STOP CONDITION (CASE 1)
TBRG
TBRG
SDAx sampled
low after TBRG,
set BCLxIF
TBRG
SDAx
SDAx asserted low
SCLx
PEN
BCLxIF
P
’0’
SSPxIF
’0’
FIGURE 15-39:
BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG
TBRG
TBRG
SDAx
SCLx goes low before SDAx goes high,
set BCLxIF
Assert SDAx
SCLx
PEN
BCLxIF
P
’0’
SSPxIF
’0’
DS41412C-page 252
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 15-3:
Name
ANSELA
REGISTERS ASSOCIATED WITH I2C™ OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSELB
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
Register
on Page
Bit 0
ANSA0
(1)
ANSB0
(1)
152
153
ANSELC
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
153
ANSELD
ANSD7
ANSD6
ANSD5
ANSD4
ANSD3
ANSD2
ANSD1(2)
ANSD0(2)
153
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
CCP5MD CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
PIR3
SSP2IF
BCL2IF
RC2IF
PMD1
MSSP2MD
MSSP1MD
—
SSP1ADD
SSP1 Address Register in I
SSP1BUF
2C
Slave Mode. SSP1 Baud Rate Reload Register in
I2C
Master Mode.
SSP1 Receive Buffer/Transmit Register
261
—
SSP1CON1
WCOL
SSPOV
SSPEN
CKP
SSP1CON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
258
SSP1CON3
ACKTIM
PCIE
SCIE
BOEN
SDAHT
SBCDE
AHEN
DHEN
259
SMP
CKE
D/A
R/W
UA
BF
SSP1MSK
SSPM<3:0>
256
SSP1 MASK Register bits
SSP1STAT
P
S
260
SSP2 Address Register in I2C Slave Mode. SSP2 Baud Rate Reload Register in I2C Master Mode.
SSP2ADD
SSP2BUF
SSP2 Receive Buffer/Transmit Register
SSP2CON1
261
—
WCOL
SSPOV
SSPEN
CKP
SSP2CON2
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
SSP2CON3
ACKTIM
PCIE
SCIE
BOEN
SDAHT
SBCDE
AHEN
DHEN
SSP2MSK
255
SSPM<3:0>
256
SSP1 MASK Register bits
258
259
260
SMP
CKE
D/A
P
S
R/W
UA
BF
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1(1)
TRISB0(1)
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1(2)
TRISD0(2)
154
SSP2STAT
Legend:
Note 1:
2:
Shaded bits are not used by the MSSPx in
PIC18(L)F2XK22 devices.
PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
I2 C
255
mode.
Preliminary
DS41412C-page 253
PIC18(L)F2X/4XK22
15.7
BAUD RATE GENERATOR
The MSSPx module has a Baud Rate Generator available for clock generation in both I2C and SPI Master
modes. The Baud Rate Generator (BRG) reload value
is placed in the SSPxADD register (Register 15-6).
When a write occurs to SSPxBUF, the Baud Rate Generator will automatically begin counting down.
Once the given operation is complete, the internal clock
will automatically stop counting and the clock pin will
remain in its last state.
module clock line. The logic dictating when the reload
signal is asserted depends on the mode the MSSPx is
being operated in.
Table 15-4 demonstrates clock rates based on
instruction cycles and the BRG value loaded into
SSPxADD.
EQUATION 15-1:
FOSC
FCLOCK = ------------------------------------------------ SSPxADD + 1   4 
An internal signal “Reload” in Figure 15-39 triggers the
value from SSPxADD to be loaded into the BRG
counter. This occurs twice for each oscillation of the
FIGURE 15-40:
BAUD RATE GENERATOR BLOCK DIAGRAM
SSPxM<3:0>
SSPxM<3:0>
Reload
SSPxADD<7:0>
Reload
Control
SCLx
SSPxCLK
BRG Down Counter
FOSC/2
Note: Values of 0x00, 0x01 and 0x02 are not valid
for SSPxADD when used as a Baud Rate
Generator for I2C. This is an implementation
limitation.
TABLE 15-4:
Note 1:
MSSPx CLOCK RATE W/BRG
FOSC
FCY
BRG Value
FCLOCK
(2 Rollovers of BRG)
32 MHz
8 MHz
13h
400 kHz(1)
32 MHz
8 MHz
19h
308 kHz
32 MHz
8 MHz
4Fh
100 kHz
16 MHz
4 MHz
09h
400 kHz(1)
16 MHz
4 MHz
0Ch
308 kHz
16 MHz
4 MHz
27h
100 kHz
4 MHz
1 MHz
09h
100 kHz
The I2C interface does not conform to the 400 kHz I2C 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.
DS41412C-page 254
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 15-1:
SSPxSTAT: SSPx STATUS REGISTER
R/W-0
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
SMP
CKE
D/A
P
S
R/W
UA
BF
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
SMP: SPI Data Input 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
In I2 C 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: SPI Clock Edge Select bit (SPI mode only)
In SPI Master or Slave mode:
1 = Transmit occurs on transition from active to Idle clock state
0 = Transmit occurs on transition from Idle to active clock state
In I2 C mode only:
1 = Enable input logic so that thresholds are compliant with SMbus specification
0 = Disable SMbus specific inputs
bit 5
D/A: Data/Address bit (I2C mode only)
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
(I2C mode only. This bit is cleared when the MSSPx module is disabled, SSPxEN is cleared.)
1 = Indicates that a Stop bit has been detected last (this bit is ‘0’ on Reset)
0 = Stop bit was not detected last
bit 3
S: Start bit
(I2C mode only. This bit is cleared when the MSSPx module is disabled, SSPxEN is cleared.)
1 = Indicates that a Start bit has been detected last (this bit is ‘0’ on Reset)
0 = Start bit was not detected last
bit 2
R/W: Read/Write bit information (I2C mode only)
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.
In I2 C Slave mode:
1 = Read
0 = Write
In I2 C Master mode:
1 = Transmit is in progress
0 = Transmit is not in progress
OR-ing this bit with SEN, RSEN, PEN, RCEN or ACKEN will indicate if the MSSPx is in Idle mode.
bit 1
UA: Update Address bit (10-bit I2C 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
Receive (SPI and I2 C modes):
1 = Receive complete, SSPxBUF is full
0 = Receive not complete, SSPxBUF is empty
Transmit (I2 C mode only):
1 = Data transmit in progress (does not include the ACK and Stop bits), SSPxBUF is full
0 = Data transmit complete (does not include the ACK and Stop bits), SSPxBUF is empty
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 255
PIC18(L)F2X/4XK22
REGISTER 15-2:
SSPxCON1: SSPx CONTROL REGISTER 1
R/C/HS-0
R/C/HS-0
R/W-0
R/W-0
WCOL
SSPxOV
SSPxEN
CKP
R/W-0
R/W-0
R/W-0
R/W-0
SSPxM<3:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
u = Bit is unchanged
x = Bit is unknown
U = Unimplemented bit, read as ‘0’
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
HS = Bit is set by hardware
C = User cleared
bit 7
WCOL: Write Collision Detect bit
Master mode:
1 = A write to the SSPxBUF register was attempted while the I2C conditions were not valid for a transmission to
be started
0 = No collision
Slave mode:
1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in software)
0 = No collision
bit 6
SSPxOV: Receive Overflow Indicator bit(1)
In SPI 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. In Slave mode, the user must read the SSPxBUF, even
if only transmitting data, to avoid setting overflow. In Master mode, the overflow bit is not set since each new reception (and transmission) is initiated by writing to the SSPxBUF register (must be cleared in software).
0 = No overflow
In I2 C mode:
1 = A byte is received while the SSPxBUF register is still holding the previous byte. SSPxOV is a “don’t care” in
Transmit mode (must be cleared in software).
0 = No overflow
bit 5
SSPxEN: Synchronous Serial Port Enable bit
In both modes, when enabled, these pins must be properly configured as input or output
In SPI mode:
1 = Enables serial port and configures SCKx, SDOx, SDIx and SSx as the source of the serial port pins(2)
0 = Disables serial port and configures these pins as I/O port pins
In I2 C mode:
1 = Enables the serial port and configures the SDAx and SCLx pins as the source of the serial port pins(3)
0 = Disables serial port and configures these pins as I/O port pins
bit 4
CKP: Clock Polarity Select bit
In SPI mode:
1 = Idle state for clock is a high level
0 = Idle state for clock is a low level
In I2 C Slave mode:
SCLx release control
1 = Enable clock
0 = Holds clock low (clock stretch). (Used to ensure data setup time.)
In I2 C Master mode:
Unused in this mode
DS41412C-page 256
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 15-2:
bit 3-0
SSPxCON1: SSPx CONTROL REGISTER 1 (CONTINUED)
SSPxM<3:0>: Synchronous Serial Port Mode Select bits
0000 = SPI Master mode, clock = FOSC/4
0001 = SPI Master mode, clock = FOSC/16
0010 = SPI Master mode, clock = FOSC/64
0011 = SPI Master mode, clock = TMR2 output/2
0100 = SPI Slave mode, clock = SCKx pin, SSx pin control enabled
0101 = SPI Slave mode, clock = SCKx pin, SSx pin control disabled, SSx can be used as I/O pin
0110 = I2C Slave mode, 7-bit address
0111 = I2C Slave mode, 10-bit address
1000 = I2C Master mode, clock = FOSC / (4 * (SSPxADD+1))(4)
1001 = Reserved
1010 = SPI Master mode, clock = FOSC/(4 * (SSPxADD+1))
1011 = I2C firmware controlled Master mode (slave idle)
1100 = Reserved
1101 = Reserved
1110 = I2C Slave mode, 7-bit address with Start and Stop bit interrupts enabled
1111 = I2C Slave mode, 10-bit address with Start and Stop bit interrupts enabled
Note 1:
2:
3:
4:
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.
When enabled, the SDAx and SCLx pins must be configured as inputs.
SSPxADD values of 0, 1 or 2 are not supported for I2C Mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 257
PIC18(L)F2X/4XK22
REGISTER 15-3:
SSPxCON2: SSPx CONTROL REGISTER 2
R/W-0
R-0
R/W-0
R/S/HC-0
R/S/HC-0
R/S/HC-0
R/S/HC-0
R/W/HC-0
GCEN
ACKSTAT
ACKDT
ACKEN(1)
RCEN(1)
PEN(1)
RSEN(1)
SEN(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
HC = Cleared by hardware
S = User set
bit 7
GCEN: General Call Enable bit (in I2C Slave mode only)
1 = Enable interrupt when a general call address (0x00 or 00h) is received in the SSPxSR
0 = General call address disabled
bit 6
ACKSTAT: Acknowledge Status bit (in I2C mode only)
1 = Acknowledge was not received
0 = Acknowledge was received
bit 5
ACKDT: Acknowledge Data bit (in I2C mode only)
In Receive mode:
Value transmitted when the user initiates an Acknowledge sequence at the end of a receive
1 = Not Acknowledge
0 = Acknowledge
bit 4
ACKEN(1): Acknowledge Sequence Enable bit (in I2C Master mode only)
In Master Receive mode:
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(1): Receive Enable bit (in I2C Master mode only)
1 = Enables Receive mode for I2C
0 = Receive idle
bit 2
PEN(1): Stop Condition Enable bit (in I2C Master mode only)
SCKx Release Control:
1 = Initiate Stop condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Stop condition Idle
bit 1
RSEN(1): Repeated Start Condition Enabled bit (in I2C Master mode only)
1 = Initiate Repeated Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Repeated Start condition Idle
bit 0
SEN(1): Start Condition Enabled bit (in I2C Master mode only)
In Master mode:
1 = Initiate Start condition on SDAx and SCLx pins. Automatically cleared by hardware.
0 = Start condition Idle
In Slave mode:
1 = Clock stretching is enabled for both slave transmit and slave receive (stretch enabled)
0 = Clock stretching is disabled
Note 1:
For bits ACKEN, RCEN, PEN, RSEN, SEN: If the I2C module is not in the Idle mode, this bit may not be
set (no spooling) and the SSPxBUF may not be written (or writes to the SSPxBUF are disabled).
DS41412C-page 258
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 15-4:
SSPxCON3: SSPx CONTROL REGISTER 3
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ACKTIM
PCIE
SCIE
BOEN
SDAHT
SBCDE
AHEN
DHEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
ACKTIM: Acknowledge Time Status bit (I2C mode only)(3)
1 = Indicates the I2C bus is in an Acknowledge sequence, set on 8th falling edge of SCLx clock
0 = Not an Acknowledge sequence, cleared on 9th rising edge of SCLx clock
bit 6
PCIE: Stop Condition Interrupt Enable bit (I2C mode only)
1 = Enable interrupt on detection of Stop condition
0 = Stop detection interrupts are disabled(2)
bit 5
SCIE: Start Condition Interrupt Enable bit (I2C mode only)
1 = Enable interrupt on detection of Start or Restart conditions
0 = Start detection interrupts are disabled(2)
bit 4
BOEN: Buffer Overwrite Enable bit
In SPI Slave mode:(1)
1 = SSPxBUF updates every time that a new data byte is shifted in ignoring the BF bit
0 = If new byte is received with BF bit of the SSPxSTAT register already set, SSPxOV bit of the
SSPxCON1 register is set, and the buffer is not updated
In I2C Master mode:
This bit is ignored.
In I2C Slave mode:
1 = SSPxBUF is updated and ACK is generated for a received address/data byte, ignoring the
state of the SSPxOV bit only if the BF bit = 0.
0 = SSPxBUF is only updated when SSPxOV is clear
bit 3
SDAHT: SDAx Hold Time Selection bit (I2C mode only)
1 = Minimum of 300 ns hold time on SDAx after the falling edge of SCLx
0 = Minimum of 100 ns hold time on SDAx after the falling edge of SCLx
bit 2
SBCDE: Slave Mode Bus Collision Detect Enable bit (I2C Slave mode only)
If on the rising edge of SCLx, SDAx is sampled low when the module is outputting a high state, the
BCLxIF bit of the PIR2 register is set, and bus goes idle
1 = Enable slave bus collision interrupts
0 = Slave bus collision interrupts are disabled
AHEN: Address Hold Enable bit (I2C Slave mode only)
1 = Following the 8th falling edge of SCLx for a matching received address byte; CKP bit of the
SSPxCON1 register will be cleared and the SCLx will be held low.
0 = Address holding is disabled
bit 1
Note 1:
2:
3:
For daisy-chained SPI operation; allows the user to ignore all but the last received byte. SSPxOV is still
set when a new byte is received and BF = 1, but hardware continues to write the most recent byte to
SSPxBUF.
This bit has no effect in Slave modes for which Start and Stop condition detection is explicitly listed as
enabled.
The ACKTIM Status bit is active only when the AHEN bit or DHEN bit is set.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 259
PIC18(L)F2X/4XK22
REGISTER 15-4:
SSPxCON3: SSPx CONTROL REGISTER 3 (CONTINUED)
DHEN: Data Hold Enable bit (I2C Slave mode only)
1 = Following the 8th falling edge of SCLx for a received data byte; slave hardware clears the CKP bit
of the SSPxCON1 register and SCLx is held low.
0 = Data holding is disabled
bit 0
Note 1:
2:
3:
For daisy-chained SPI operation; allows the user to ignore all but the last received byte. SSPxOV is still
set when a new byte is received and BF = 1, but hardware continues to write the most recent byte to
SSPxBUF.
This bit has no effect in Slave modes for which Start and Stop condition detection is explicitly listed as
enabled.
The ACKTIM Status bit is active only when the AHEN bit or DHEN bit is set.
REGISTER 15-5:
SSPxMSK: SSPx MASK 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
MSK7
MSK6
MSK5
MSK4
MSK3
MSK2
MSK1
MSK0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-1
MSK<7:1>: Mask bits
1 = The received address bit n is compared to SSPxADD<n> to detect I2C address match
0 = The received address bit n is not used to detect I2C address match
bit 0
MSK<0>: Mask bit for I2C Slave mode, 10-bit Address
I2C Slave mode, 10-bit address (SSPxM<3:0> = 0111 or 1111):
1 = The received address bit 0 is compared to SSPxADD<0> to detect I2C address match
0 = The received address bit 0 is not used to detect I2C address match
I2C Slave mode, 7-bit address, the bit is ignored
DS41412C-page 260
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
SSPXADD: MSSPx ADDRESS AND BAUD RATE REGISTER (I2C MODE)
REGISTER 15-6:
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ADD<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
Master mode:
bit 7-0
ADD<7:0>: Baud Rate Clock Divider bits
SCLx pin clock period = ((ADD<7:0> + 1) *4)/FOSC
10-Bit Slave mode — Most Significant Address byte:
bit 7-3
Not used: Unused for Most Significant Address byte. Bit state of this register is a “don’t care”. Bit
pattern sent by master is fixed by I2C specification and must be equal to ‘11110’. However, those bits
are compared by hardware and are not affected by the value in this register.
bit 2-1
ADD<2:1>: Two Most Significant bits of 10-bit address
bit 0
Not used: Unused in this mode. Bit state is a “don’t care”.
10-Bit Slave mode — Least Significant Address byte:
bit 7-0
ADD<7:0>: Eight Least Significant bits of 10-bit address
7-Bit Slave mode:
bit 7-1
ADD<7:1>: 7-bit address
bit 0
Not used: Unused in this mode. Bit state is a “don’t care”.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 261
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 262
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.0
ENHANCED UNIVERSAL
SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (EUSART)
The EUSART module includes the following capabilities:
•
•
•
•
•
•
•
•
•
•
The Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART) module is a serial I/O
communications peripheral. It contains all the clock
generators, shift registers and data buffers necessary
to perform an input or output serial data transfer
independent of device program execution. The
EUSART, also known as a Serial Communications
Interface (SCI), can be configured as a full-duplex
asynchronous system or half-duplex synchronous
system.
Full-Duplex
mode
is
useful
for
communications with peripheral systems, such as CRT
terminals and personal computers. Half-Duplex
Synchronous mode is intended for communications
with peripheral devices, such as A/D or D/A integrated
circuits, serial EEPROMs or other microcontrollers.
These devices typically do not have internal clocks for
baud rate generation and require the external clock
signal provided by a master synchronous device.
FIGURE 16-1:
Full-duplex asynchronous transmit and receive
Two-character input buffer
One-character output buffer
Programmable 8-bit or 9-bit character length
Address detection in 9-bit mode
Input buffer overrun error detection
Received character framing error detection
Half-duplex synchronous master
Half-duplex synchronous slave
Programmable clock and data polarity
The EUSART module implements the following
additional features, making it ideally suited for use in
Local Interconnect Network (LIN) bus systems:
• Automatic detection and calibration of the baud rate
• Wake-up on Break reception
• 13-bit Break character transmit
Block diagrams of the EUSART transmitter and
receiver are shown in Figure 16-1 and Figure 16-2.
EUSART TRANSMIT BLOCK DIAGRAM
Data Bus
TXxIE
Interrupt
TXxIF
TXREGx Register
8
MSb
LSb
(8)
0
• • •
TXx/CKx pin
Pin Buffer
and Control
Transmit Shift Register (TSR)
TXEN
TRMT
Baud Rate Generator
FOSC
TX9
n
BRG16
+1
SPBRGHx
÷n
SPBRGx
Multiplier
x4
x16 x64
SYNC
1 X 0 0
0
BRGH
X 1 1 0
0
BRG16
X 1 0 1
0
 2010 Microchip Technology Inc.
TX9D
Preliminary
DS41412C-page 263
PIC18(L)F2X/4XK22
FIGURE 16-2:
EUSART RECEIVE BLOCK DIAGRAM
CREN
RXx/DTx pin
Baud Rate Generator
Data
Recovery
FOSC
SPBRGHx
SPBRGx
x4
x16 x64
SYNC
1 X 0 0
0
BRGH
X 1 1 0
0
BRG16
X 1 0 1
0
(8)
•••
7
1
LSb
0 START
RX9
÷n
BRG16
Multiplier
Stop
RCIDL
RSR Register
MSb
Pin Buffer
and Control
+1
OERR
n
FERR
RX9D
RCREGx Register
8
FIFO
Data Bus
RCxIF
RCxIE
Interrupt
The operation of the EUSART module is controlled
through three registers:
• Transmit Status and Control (TXSTAx)
• Receive Status and Control (RCSTAx)
• Baud Rate Control (BAUDCONx)
These registers are detailed in Register 16-1,
Register 16-2 and Register 16-3, respectively.
For all modes of EUSART operation, the TRIS control
bits corresponding to the RXx/DTx and TXx/CKx pins
should be set to ‘1’. The EUSART control will
automatically reconfigure the pin from input to output, as
needed.
When the receiver or transmitter section is not enabled
then the corresponding RXx/DTx or TXx/CKx pin may be
used for general purpose input and output.
DS41412C-page 264
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.1
EUSART Asynchronous Mode
16.1.1.2
The EUSART transmits and receives data using the
standard non-return-to-zero (NRZ) format. NRZ is
implemented with two levels: a VOH mark state which
represents a ‘1’ data bit, and a VOL space state which
represents a ‘0’ data bit. NRZ refers to the fact that
consecutively transmitted data bits of the same value
stay at the output level of that bit without returning to a
neutral level between each bit transmission. An NRZ
transmission port idles in the mark state. Each character
transmission consists of one Start bit followed by eight
or nine data bits and is always terminated by one or
more Stop bits. The Start bit is always a space and the
Stop bits are always marks. The most common data
format is 8 bits. Each transmitted bit persists for a period
of 1/(Baud Rate). An on-chip dedicated 8-bit/16-bit Baud
Rate Generator is used to derive standard baud rate
frequencies from the system oscillator. See Table 16-5
for examples of baud rate configurations.
Transmitting Data
A transmission is initiated by writing a character to the
TXREGx register. If this is the first character, or the
previous character has been completely flushed from
the TSR, the data in the TXREGx is immediately
transferred to the TSR register. If the TSR still contains
all or part of a previous character, the new character
data is held in the TXREGx until the Stop bit of the
previous character has been transmitted. The pending
character in the TXREGx is then transferred to the TSR
in one TCY immediately following the Stop bit
transmission. The transmission of the Start bit, data bits
and Stop bit sequence commences immediately
following the transfer of the data to the TSR from the
TXREGx.
16.1.1.3
Transmit Data Polarity
The EUSART transmits and receives the LSb first. The
EUSART’s transmitter and receiver are functionally
independent, but share the same data format and baud
rate. Parity is not supported by the hardware, but can
be implemented in software and stored as the ninth
data bit.
The polarity of the transmit data can be controlled with
the CKTXP bit of the BAUDCONx register. The default
state of this bit is ‘0’ which selects high true transmit
idle and data bits. Setting the CKTXP bit to ‘1’ will invert
the transmit data resulting in low true idle and data bits.
The CKTXP bit controls transmit data polarity only in
Asynchronous mode. In Synchronous mode the
CKTXP bit has a different function.
16.1.1
16.1.1.4
EUSART ASYNCHRONOUS
TRANSMITTER
The EUSART transmitter block diagram is shown in
Figure 16-1. The heart of the transmitter is the serial
Transmit Shift Register (TSR), which is not directly
accessible by software. The TSR obtains its data from
the transmit buffer, which is the TXREGx register.
16.1.1.1
Enabling the Transmitter
The EUSART transmitter is enabled for asynchronous
operations by configuring the following three control
bits:
• TXEN = 1
• SYNC = 0
• SPEN = 1
All other EUSART control bits are assumed to be in
their default state.
Setting the TXEN bit of the TXSTAx register enables the
transmitter circuitry of the EUSART. Clearing the SYNC
bit of the TXSTAx register configures the EUSART for
asynchronous operation. Setting the SPEN bit of the
RCSTAx register enables the EUSART and
automatically configures the TXx/CKx I/O pin as an
output. If the TXx/CKx pin is shared with an analog
peripheral the analog I/O function must be disabled by
clearing the corresponding ANSEL bit.
Note:
Transmit Interrupt Flag
The TXxIF interrupt flag bit of the PIR1/PIR3 register is
set whenever the EUSART transmitter is enabled and
no character is being held for transmission in the
TXREGx. In other words, the TXxIF bit is only clear
when the TSR is busy with a character and a new
character has been queued for transmission in the
TXREGx. The TXxIF flag bit is not cleared immediately
upon writing TXREGx. TXxIF becomes valid in the
second instruction cycle following the write execution.
Polling TXxIF immediately following the TXREGx write
will return invalid results. The TXxIF bit is read-only, it
cannot be set or cleared by software.
The TXxIF interrupt can be enabled by setting the
TXxIE interrupt enable bit of the PIE1/PIE3 register.
However, the TXxIF flag bit will be set whenever the
TXREGx is empty, regardless of the state of TXxIE
enable bit.
To use interrupts when transmitting data, set the TXxIE
bit only when there is more data to send. Clear the
TXxIE interrupt enable bit upon writing the last
character of the transmission to the TXREGx.
The TXxIF transmitter interrupt flag is set
when the TXEN enable bit is set.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 265
PIC18(L)F2X/4XK22
16.1.1.5
TSR Status
16.1.1.7
The TRMT bit of the TXSTAx register indicates the
status of the TSR register. This is a read-only bit. The
TRMT bit is set when the TSR register is empty and is
cleared when a character is transferred to the TSR
register from the TXREGx. The TRMT bit remains clear
until all bits have been shifted out of the TSR register.
No interrupt logic is tied to this bit, so the user needs to
poll this bit to determine the TSR status.
Note:
16.1.1.6
The TSR register is not mapped in data
memory, so it is not available to the user.
1.
2.
3.
4.
Transmitting 9-Bit Characters
The EUSART supports 9-bit character transmissions.
When the TX9 bit of the TXSTAx register is set the
EUSART will shift 9 bits out for each character transmitted. The TX9D bit of the TXSTAx register is the ninth,
and Most Significant, data bit. When transmitting 9-bit
data, the TX9D data bit must be written before writing
the 8 Least Significant bits into the TXREGx. All nine
bits of data will be transferred to the TSR shift register
immediately after the TXREGx is written.
5.
A special 9-bit Address mode is available for use with
multiple receivers. See Section 16.1.2.8 “Address
Detection” for more information on the Address mode.
8.
FIGURE 16-3:
Write to TXREGx
BRG Output
(Shift Clock)
TXx/CKx pin
TXxIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
DS41412C-page 266
6.
7.
9.
Asynchronous Transmission Set-up:
Initialize the SPBRGHx:SPBRGx register pair
and the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 16.3 “EUSART
Baud Rate Generator (BRG)”).
Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
Enable the asynchronous serial port by clearing
the SYNC bit and setting the SPEN bit.
If 9-bit transmission is desired, set the TX9 control bit. A set ninth data bit will indicate that the 8
Least Significant data bits are an address when
the receiver is set for address detection.
Set the CKTXP control bit if inverted transmit
data polarity is desired.
Enable the transmission by setting the TXEN
control bit. This will cause the TXxIF interrupt bit
to be set.
If interrupts are desired, set the TXxIE interrupt
enable bit. An interrupt will occur immediately
provided that the GIE/GIEH and PEIE/GIEL bits
of the INTCON register are also set.
If 9-bit transmission is selected, the ninth bit
should be loaded into the TX9D data bit.
Load 8-bit data into the TXREGx register. This
will start the transmission.
ASYNCHRONOUS TRANSMISSION
Word 1
Start bit
bit 0
bit 1
bit 7/8
Stop bit
Word 1
1 TCY
Word 1
Transmit Shift Reg
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 16-4:
ASYNCHRONOUS TRANSMISSION (BACK-TO-BACK)
Write to TXREGx
TXx/CKx pin
Start bit
bit 0
bit 1
Word 1
1 TCY
TXxIF bit
(Interrupt Reg. Flag)
bit 7/8
Stop bit
Start bit
bit 0
Word 2
1 TCY
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Note:
Word 2
Word 1
BRG Output
(Shift Clock)
Word 1
Transmit Shift Reg
Word 2
Transmit Shift Reg
This timing diagram shows two consecutive transmissions.
TABLE 16-1:
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on
Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
TMR2IP
TMR1IP
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
SSP2IF
BCL2IF
RC2IF
PIR3
PMD0
SPEN
RX9
RCSTA2
SPEN
RX9
TMR2IE
TMR1IE
TMR3GIE TMR1GIE
TMR2IF
127
129
123
125
TMR1IF
118
120
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
TMR5MD
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
UART2MD UART1MD TMR6MD
RCSTA1
TMR3GIP TMR1GIP
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
—
TXREG1
TXSTA1
EUSART1 Transmit Register
CSRC
TX9
TXEN
TXREG2
TXSTA2
Legend:
SYNC
SENDB
—
BRGH
TRMT
TX9D
EUSART2 Transmit Register
CSRC
TX9
TXEN
SYNC
SENDB
272
—
BRGH
TRMT
TX9D
272
— = unimplemented locations, read as ‘0’. Shaded bits are not used for asynchronous transmission.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 267
PIC18(L)F2X/4XK22
16.1.2
EUSART ASYNCHRONOUS
RECEIVER
16.1.2.2
The Asynchronous mode would typically be used in
RS-232 systems. The receiver block diagram is shown
in Figure 16-2. The data is received on the RXx/DTx
pin and drives the data recovery block. The data
recovery block is actually a high-speed shifter
operating at 16 times the baud rate, whereas the serial
Receive Shift Register (RSR) operates at the bit rate.
When all 8 or 9 bits of the character have been shifted
in, they are immediately transferred to a two character
First-In-First-Out (FIFO) memory. The FIFO buffering
allows reception of two complete characters and the
start of a third character before software must start
servicing the EUSART receiver. The FIFO and RSR
registers are not directly accessible by software.
Access to the received data is via the RCREGx
register.
16.1.2.1
Enabling the Receiver
The EUSART receiver is enabled for asynchronous
operation by configuring the following three control bits:
• CREN = 1
• SYNC = 0
• SPEN = 1
All other EUSART control bits are assumed to be in
their default state.
Setting the CREN bit of the RCSTAx register enables
the receiver circuitry of the EUSART. Clearing the
SYNC bit of the TXSTAx register configures the
EUSART for asynchronous operation. Setting the
SPEN bit of the RCSTAx register enables the
EUSART. The RXx/DTx I/O pin must be configured as
an input by setting the corresponding TRIS control bit.
If the RXx/DTx pin is shared with an analog peripheral
the analog I/O function must be disabled by clearing
the corresponding ANSEL bit.
DS41412C-page 268
Receiving Data
The receiver data recovery circuit initiates character
reception on the falling edge of the first bit. The first bit,
also known as the Start bit, is always a zero. The data
recovery circuit counts one-half bit time to the center of
the Start bit and verifies that the bit is still a zero. If it is
not a zero then the data recovery circuit aborts
character reception, without generating an error, and
resumes looking for the falling edge of the Start bit. If
the Start bit zero verification succeeds then the data
recovery circuit counts a full bit time to the center of the
next bit. The bit is then sampled by a majority detect
circuit and the resulting ‘0’ or ‘1’ is shifted into the RSR.
This repeats until all data bits have been sampled and
shifted into the RSR. One final bit time is measured and
the level sampled. This is the Stop bit, which is always
a ‘1’. If the data recovery circuit samples a ‘0’ in the
Stop bit position then a framing error is set for this
character, otherwise the framing error is cleared for this
character. See Section 16.1.2.5 “Receive Framing
Error” for more information on framing errors.
Immediately after all data bits and the Stop bit have
been received, the character in the RSR is transferred
to the EUSART receive FIFO and the RCxIF interrupt
flag bit of the PIR1/PIR3 register is set. The top character in the FIFO is transferred out of the FIFO by reading
the RCREGx register.
Note:
16.1.2.3
If the receive FIFO is overrun, no additional
characters will be received until the overrun
condition is cleared. See Section 16.1.2.6
“Receive Overrun Error” for more
information on overrun errors.
Receive Data Polarity
The polarity of the receive data can be controlled with
the DTRXP bit of the BAUDCONx register. The default
state of this bit is ‘0’ which selects high true receive idle
and data bits. Setting the DTRXP bit to ‘1’ will invert the
receive data resulting in low true idle and data bits. The
DTRXP bit controls receive data polarity only in Asynchronous mode. In Synchronous mode the DTRXP bit
has a different function.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.1.2.4
Receive Interrupts
16.1.2.7
The RCxIF interrupt flag bit of the PIR1/PIR3 register is
set whenever the EUSART receiver is enabled and
there is an unread character in the receive FIFO. The
RCxIF interrupt flag bit is read-only, it cannot be set or
cleared by software.
RCxIF interrupts are enabled by setting the following
bits:
• RCxIE interrupt enable bit of the PIE1/PIE3
register
• PEIE/GIEL peripheral interrupt enable bit of the
INTCON register
• GIE/GIEH global interrupt enable bit of the
INTCON register
16.1.2.5
The EUSART supports 9-bit character reception. When
the RX9 bit of the RCSTAx register is set, the EUSART
will shift 9 bits into the RSR for each character
received. The RX9D bit of the RCSTAx register is the
ninth and Most Significant data bit of the top unread
character in the receive FIFO. When reading 9-bit data
from the receive FIFO buffer, the RX9D data bit must
be read before reading the 8 Least Significant bits from
the RCREGx.
16.1.2.8
The RCxIF interrupt flag bit will be set when there is an
unread character in the FIFO, regardless of the state of
interrupt enable bits.
Receive Framing Error
Each character in the receive FIFO buffer has a
corresponding framing error Status bit. A framing error
indicates that a Stop bit was not seen at the expected
time. The framing error status is accessed via the
FERR bit of the RCSTAx register. The FERR bit
represents the status of the top unread character in the
receive FIFO. Therefore, the FERR bit must be read
before reading the RCREG.x
The FERR bit is read-only and only applies to the top
unread character in the receive FIFO. A framing error
(FERR = 1) does not preclude reception of additional
characters. It is not necessary to clear the FERR bit.
Reading the next character from the FIFO buffer will
advance the FIFO to the next character and the next
corresponding framing error.
Receiving 9-bit Characters
Address Detection
A special Address Detection mode is available for use
when multiple receivers share the same transmission
line, such as in RS-485 systems. Address detection is
enabled by setting the ADDEN bit of the RCSTAx
register.
Address detection requires 9-bit character reception.
When address detection is enabled, only characters
with the ninth data bit set will be transferred to the
receive FIFO buffer, thereby setting the RCxIF interrupt
bit. All other characters will be ignored.
Upon receiving an address character, user software
determines if the address matches its own. Upon
address match, user software must disable address
detection by clearing the ADDEN bit before the next
Stop bit occurs. When user software detects the end of
the message, determined by the message protocol
used, software places the receiver back into the
Address Detection mode by setting the ADDEN bit.
The FERR bit can be forced clear by clearing the SPEN
bit of the RCSTAx register which resets the EUSART.
Clearing the CREN bit of the RCSTAx register does not
affect the FERR bit. A framing error by itself does not
generate an interrupt.
Note:
16.1.2.6
If all receive characters in the receive
FIFO have framing errors, repeated reads
of the RCREGx will not clear the FERR bit.
Receive Overrun Error
The receive FIFO buffer can hold two characters. An
overrun error will be generated if a third character, in its
entirety, is received before the FIFO is accessed. When
this happens the OERR bit of the RCSTAx register is
set. The characters already in the FIFO buffer can be
read but no additional characters will be received until
the error is cleared. The error must be cleared by either
clearing the CREN bit of the RCSTAx register or by
resetting the EUSART by clearing the SPEN bit of the
RCSTAx register.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 269
PIC18(L)F2X/4XK22
16.1.2.9
Asynchronous Reception Set-up:
1.
16.1.2.10
Initialize the SPBRGHx:SPBRGx register pair
and the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 16.3 “EUSART
Baud Rate Generator (BRG)”).
2. Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
3. Enable the serial port by setting the SPEN bit
and the RXx/DTx pin TRIS bit. The SYNC bit
must be clear for asynchronous operation.
4. If interrupts are desired, set the RCxIE interrupt
enable bit and set the GIE/GIEH and PEIE/GIEL
bits of the INTCON register.
5. If 9-bit reception is desired, set the RX9 bit.
6. Set the DTRXP if inverted receive polarity is
desired.
7. Enable reception by setting the CREN bit.
8. The RCxIF interrupt flag bit will be set when a
character is transferred from the RSR to the
receive buffer. An interrupt will be generated if
the RCxIE interrupt enable bit was also set.
9. Read the RCSTAx register to get the error flags
and, if 9-bit data reception is enabled, the ninth
data bit.
10. Get the received 8 Least Significant data bits
from the receive buffer by reading the RCREGx
register.
11. If an overrun occurred, clear the OERR flag by
clearing the CREN receiver enable bit.
This mode would typically be used in RS-485 systems.
To set up an Asynchronous Reception with Address
Detect Enable:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
DS41412C-page 270
9-bit Address Detection Mode Set-up
Preliminary
Initialize the SPBRGHx, SPBRGx register pair
and the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 16.3 “EUSART
Baud Rate Generator (BRG)”).
Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
Enable the serial port by setting the SPEN bit.
The SYNC bit must be clear for asynchronous
operation.
If interrupts are desired, set the RCxIE interrupt
enable bit and set the GIE/GIEH and PEIE/GIEL
bits of the INTCON register.
Enable 9-bit reception by setting the RX9 bit.
Enable address detection by setting the ADDEN
bit.
Set the DTRXP if inverted receive polarity is
desired.
Enable reception by setting the CREN bit.
The RCxIF interrupt flag bit will be set when a
character with the ninth bit set is transferred
from the RSR to the receive buffer. An interrupt
will be generated if the RCxIE interrupt enable
bit was also set.
Read the RCSTAx register to get the error flags.
The ninth data bit will always be set.
Get the received 8 Least Significant data bits
from the receive buffer by reading the RCREGx
register. Software determines if this is the
device’s address.
If an overrun occurred, clear the OERR flag by
clearing the CREN receiver enable bit.
If the device has been addressed, clear the
ADDEN bit to allow all received data into the
receive buffer and generate interrupts.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 16-5:
ASYNCHRONOUS RECEPTION
Start
bit
bit 0
RXx/DTx pin
bit 1
bit 7/8 Stop
bit
Rcv Shift
Reg
Rcv Buffer Reg
Start
bit
bit 7/8 Stop
bit
bit 0
bit 7/8 Stop
bit
Word 2
RCREGx
Word 1
RCREGx
RCIDL
Start
bit
Read Rcv
Buffer Reg
RCREGx
RCxIF
(Interrupt Flag)
OERR bit
CREN
Note:
This timing diagram shows three words appearing on the RXx/DTx input. The RCREGx (receive buffer) is read after the third
word, causing the OERR (overrun) bit to be set.
TABLE 16-2:
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
PMD0
UART2MD
UART1MD TMR6MD TMR5MD TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
FERR
OERR
RX9D
273
FERR
OERR
RX9D
273
RCREG1
RCSTA1
EUSART1 Receive Register
SPEN
RX9
SREN
SPEN
RX9
SREN
RCREG2
RCSTA2
CREN
ADDEN
—
EUSART2 Receive Register
CREN
ADDEN
—
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
—
TRISB(2)
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
TXSTA1
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TXSTA2
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TRISD
Legend:
Note
— = unimplemented locations, read as ‘0’. Shaded bits are not used for asynchronous reception.
1:
PIC18(L)F4XK22 devices.
2:
PIC18(L)F2XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 271
PIC18(L)F2X/4XK22
16.2
Clock Accuracy with
Asynchronous Operation
The factory calibrates the internal oscillator block
output (HFINTOSC). However, the HFINTOSC
frequency may drift as VDD or temperature changes,
and this directly affects the asynchronous baud rate.
Two methods may be used to adjust the baud rate
clock, but both require a reference clock source of
some kind.
REGISTER 16-1:
The first (preferred) method uses the OSCTUNE
register to adjust the HFINTOSC output. Adjusting the
value in the OSCTUNE register allows for fine resolution
changes to the system clock source. See Section 2.5
“Internal Clock Modes” for more information.
The other method adjusts the value in the Baud Rate
Generator. This can be done automatically with the
Auto-Baud Detect feature (see Section 16.3.1 “AutoBaud Detect”). There may not be fine enough
resolution when adjusting the Baud Rate Generator to
compensate for a gradual change in the peripheral
clock frequency.
TXSTAX: 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: Ninth bit of Transmit Data
Can be address/data bit or a parity bit.
Note 1:
SREN/CREN overrides TXEN in Sync mode.
DS41412C-page 272
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 16-2:
RCSTAX: 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 RXx/DTx and TXx/CKx 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, enable interrupt and load 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 8-bit (RX9 = 0):
Don’t care
bit 2
FERR: Framing Error bit
1 = Framing error (can be updated by reading RCREGx register and receive 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: Ninth bit of Received Data
This can be address/data bit or a parity bit and must be calculated by user firmware.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 273
PIC18(L)F2X/4XK22
REGISTER 16-3:
BAUDCONX: BAUD RATE CONTROL REGISTER
R/W-0
R-1
R/W-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
ABDOVF
RCIDL
DTRXP
CKTXP
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 Detect Overflow bit
Asynchronous mode:
1 = Auto-baud timer overflowed
0 = Auto-baud timer did not overflow
Synchronous mode:
Don’t care
bit 6
RCIDL: Receive Idle Flag bit
Asynchronous mode:
1 = Receiver is Idle
0 = Start bit has been detected and the receiver is active
Synchronous mode:
Don’t care
bit 5
DTRXP: Data/Receive Polarity Select bit
Asynchronous mode:
1 = Receive data (RXx) is inverted (active-low)
0 = Receive data (RXx) is not inverted (active-high)
Synchronous mode:
1 = Data (DTx) is inverted (active-low)
0 = Data (DTx) is not inverted (active-high)
bit 4
CKTXP: Clock/Transmit Polarity Select bit
Asynchronous mode:
1 = Idle state for transmit (TXx) is low
0 = Idle state for transmit (TXx) is high
Synchronous mode:
1 = Data changes on the falling edge of the clock and is sampled on the rising edge of the clock
0 = Data changes on the rising edge of the clock and is sampled on the falling edge of the clock
bit 3
BRG16: 16-bit Baud Rate Generator bit
1 = 16-bit Baud Rate Generator is used (SPBRGHx:SPBRGx)
0 = 8-bit Baud Rate Generator is used (SPBRGx)
bit 2
Unimplemented: Read as ‘0’
bit 1
WUE: Wake-up Enable bit
Asynchronous mode:
1 = Receiver is waiting for a falling edge. No character will be received but RCxIF will be set on the falling
edge. WUE will automatically clear on the rising edge.
0 = Receiver is operating normally
Synchronous mode:
Don’t care
bit 0
ABDEN: Auto-Baud Detect Enable bit
Asynchronous mode:
1 = Auto-Baud Detect mode is enabled (clears when auto-baud is complete)
0 = Auto-Baud Detect mode is disabled
Synchronous mode:
Don’t care
DS41412C-page 274
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.3
EUSART Baud Rate Generator
(BRG)
The Baud Rate Generator (BRG) is an 8-bit or 16-bit
timer that is dedicated to the support of both the
asynchronous and synchronous EUSART operation.
By default, the BRG operates in 8-bit mode. Setting the
BRG16 bit of the BAUDCONx register selects 16-bit
mode.
The SPBRGHx:SPBRGx register pair determines the
period of the free running baud rate timer. In
Asynchronous mode the multiplier of the baud rate
period is determined by both the BRGH bit of the
TXSTAx register and the BRG16 bit of the BAUDCONx
register. In Synchronous mode, the BRGH bit is ignored.
If the system clock is changed during an active receive
operation, a receive error or data loss may result. To
avoid this problem, check the status of the RCIDL bit to
make sure that the receive operation is Idle before
changing the system clock.
EXAMPLE 16-1:
For a device with FOSC of 16 MHz, desired baud rate
of 9600, Asynchronous mode, 8-bit BRG:
F OS C
Desired Baud Rate = -------------------------------------------------------------------------64  [SPBRGHx:SPBRGx] + 1 
Solving for SPBRGHx:SPBRGx:
FOSC
--------------------------------------------Desired Baud Rate
X = --------------------------------------------- – 1
64
Table contains the formulas for determining the baud
rate. Example 16-1 provides a sample calculation for
determining the baud rate and baud rate error.
Typical baud rates and error values for various
Asynchronous modes have been computed for your
convenience and are shown in Table 16-5. It may be
advantageous to use the high baud rate (BRGH = 1),
or the 16-bit BRG (BRG16 = 1) to reduce the baud rate
error. The 16-bit BRG mode is used to achieve slow
baud rates for fast oscillator frequencies.
16000000
-----------------------9600
= ------------------------ – 1
64
=  25.042  = 25
16000000
Calculated Baud Rate = --------------------------64  25 + 1 
Writing a new value to the SPBRGHx, SPBRGx
register pair causes the BRG timer to be reset (or
cleared). This ensures that the BRG does not wait for a
timer overflow before outputting the new baud rate.
TABLE 16-3:
Calc. Baud Rate – Desired Baud Rate
Error = -------------------------------------------------------------------------------------------Desired Baud Rate
 9615 – 9600 
= ---------------------------------- = 0.16%
9600
BRG/EUSART Mode
Baud Rate Formula
0
8-bit/Asynchronous
FOSC/[64 (n+1)]
0
1
8-bit/Asynchronous
1
0
16-bit/Asynchronous
SYNC
BRG16
BRGH
0
0
0
0
0
1
1
16-bit/Asynchronous
1
0
x
8-bit/Synchronous
1
x
16-bit/Synchronous
1
= 9615
BAUD RATE FORMULAS
Configuration Bits
Legend:
CALCULATING BAUD
RATE ERROR
FOSC/[16 (n+1)]
FOSC/[4 (n+1)]
x = Don’t care, n = value of SPBRGHx, SPBRGx register pair.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 275
PIC18(L)F2X/4XK22
TABLE 16-4:
REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
RCSTA1
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
RCSTA2
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
PMD0
TMR3MD TMR2MD TMR1MD
56
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
PIR1
—
ADIF
RC1IF
PIR3
SSP2IF
BCL2IF
CSRC
TX9
CSRC
TX9
TXSTA1
TXSTA2
Legend:
—
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
RC2IF
TX2IF
CTMUIF
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TMR5GIF TMR3GIF TMR1GIF
120
— = unimplemented, read as ‘0’. Shaded bits are not used by the BRG.
TABLE 16-5:
BAUD RATES FOR ASYNCHRONOUS MODES
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
300
FOSC = 64.000 MHz
FOSC = 18.432 MHz
FOSC = 16.000 MHz
FOSC = 11.0592 MHz
Actual
Rate
%
Error
SPBRxG
value
(decimal)
—
—
—
—
—
—
—
—
—
—
—
—
—
1200
0.00
239
1202
0.16
207
1200
0.00
143
Actual
Rate
%
Error
SPBRGx
value
(decimal)
Actual
Rate
%
Error
SPBRGx
value
(decimal)
Actual
Rate
%
Error
SPBRGx
value
(decimal)
1200
—
—
2400
—
—
—
2400
0.00
119
2404
0.16
103
2400
0.00
71
9600
9615
0.16
103
9600
0.00
29
9615
0.16
25
9600
0.00
17
10417
10417
0.00
95
10286
-1.26
27
10417
0.00
23
10165
-2.42
16
19.2k
19.23k
0.16
51
19.20k
0.00
14
19.23k
0.16
12
19.20k
0.00
8
57.6k
58.82k
2.12
16
57.60k
0.00
7
—
—
—
57.60k
0.00
2
115.2k
111.11k
-3.55
8
—
—
—
—
—
—
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
FOSC = 8.000 MHz
Actual
Rate
%
Error
SPBRGx
value
(decimal)
FOSC = 4.000 MHz
Actual
Rate
FOSC = 3.6864 MHz
%
Error
SPBRGx
value
(decimal)
Actual
Rate
FOSC = 1.000 MHz
%
Error
SPBRGx
value
(decimal)
Actual
Rate
%
Error
SPBRGx
value
(decimal)
300
—
—
—
300
0.16
207
300
0.00
191
300
0.16
51
1200
1202
0.16
103
1202
0.16
51
1200
0.00
47
1202
0.16
12
2400
2404
0.16
51
2404
0.16
25
2400
0.00
23
—
—
—
9600
9615
0.16
12
—
—
—
9600
0.00
5
—
—
—
10417
10417
0.00
11
10417
0.00
5
—
—
—
—
—
—
19.2k
—
—
—
—
—
—
19.20k
0.00
2
—
—
—
57.6k
—
—
—
—
—
—
57.60k
0.00
0
—
—
—
115.2k
—
—
—
—
—
—
—
—
—
—
—
—
DS41412C-page 276
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 16-5:
BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
FOSC = 64.000 MHz
Actual
Rate
%
Error
SPBRGx
value
(decimal)
FOSC = 18.432 MHz
Actual
Rate
%
Error
SPBRGx
value
(decimal)
FOSC = 16.000 MHz
Actual
Rate
%
Error
FOSC = 11.0592 MHz
SPBRGx
value
(decimal)
Actual
Rate
%
Error
SPBRGx
value
(decimal)
300
—
—
—
—
—
—
—
—
—
—
—
—
1200
—
—
—
—
—
—
—
—
—
—
—
—
2400
—
—
—
—
—
—
—
—
—
—
—
—
9600
—
—
—
9600
0.00
119
9615
0.16
103
9600
0.00
71
10417
—
—
—
10378
-0.37
110
10417
0.00
95
10473
0.53
65
19.2k
19.23k
0.16
207
19.20k
0.00
59
19.23k
0.16
51
19.20k
0.00
35
57.6k
57.97k
0.64
68
57.60k
0.00
19
58.82k
2.12
16
57.60k
0.00
11
115.2k
114.29k
-0.79
34
115.2k
0.00
9
111.1k
-3.55
8
115.2k
0.00
5
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
FOSC = 8.000 MHz
Actual
Rate
%
Error
FOSC = 4.000 MHz
SPBRGx
value
(decimal)
Actual
Rate
%
Error
FOSC = 3.6864 MHz
SPBRGx
value
(decimal)
Actual
Rate
%
Error
FOSC = 1.000 MHz
SxBRGx
value
(decimal)
Actual
Rate
%
Error
SPBRGx
value
(decimal)
207
300
—
—
—
—
—
—
—
—
—
300
0.16
1200
—
—
—
1202
0.16
207
1200
0.00
191
1202
0.16
51
2400
2404
0.16
207
2404
0.16
103
2400
0.00
95
2404
0.16
25
—
9600
9615
0.16
51
9615
0.16
25
9600
0.00
23
—
—
10417
10417
0.00
47
10417
0.00
23
10473
0.53
21
10417
0.00
5
19.2k
19231
0.16
25
19.23k
0.16
12
19.2k
0.00
11
—
—
—
57.6k
55556
-3.55
8
—
—
—
57.60k
0.00
3
—
—
—
115.2k
—
—
—
—
—
—
115.2k
0.00
1
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
FOSC = 64.000 MHz
Actual
Rate
FOSC = 18.432 MHz
%
Error
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
FOSC = 16.000 MHz
FOSC = 11.0592 MHz
Actual
Rate
%
Error
SPBRGHx
:SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
300
300.0
0.00
13332
300.0
0.00
3839
300.03
0.01
3332
300.0
0.00
2303
1200
1200.1
0.01
3332
1200
0.00
959
1200.5
0.04
832
1200
0.00
575
2400
2399
-0.02
1666
2400
0.00
479
2398
-0.08
416
2400
0.00
287
9600
9592
-0.08
416
9600
0.00
119
9615
0.16
103
9600
0.00
71
10417
10417
0.00
383
10378
-0.37
110
10417
0.00
95
10473
0.53
65
19.2k
19.23k
0.16
207
19.20k
0.00
59
19.23k
0.16
51
19.20k
0.00
35
57.6k
57.97k
0.64
68
57.60k
0.00
19
58.82k
2.12
16
57.60k
0.00
11
115.2k
114.29k
-0.79
34
115.2k
0.00
9
111.11k
-3.55
8
115.2k
0.00
5
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 277
PIC18(L)F2X/4XK22
TABLE 16-5:
BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
FOSC = 8.000 MHz
FOSC = 4.000 MHz
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
%
Error
FOSC = 3.6864 MHz
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
%
Error
FOSC = 1.000 MHz
SPBRGHx
:SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
207
300
299.9
-0.02
1666
300.1
0.04
832
300.0
0.00
767
300.5
0.16
1200
1199
-0.08
416
1202
0.16
207
1200
0.00
191
1202
0.16
51
2400
2404
0.16
207
2404
0.16
103
2400
0.00
95
2404
0.16
25
—
9600
9615
0.16
51
9615
0.16
25
9600
0.00
23
—
—
10417
10417
0.00
47
10417
0.00
23
10473
0.53
21
10417
0.00
5
19.2k
19.23k
0.16
25
19.23k
0.16
12
19.20k
0.00
11
—
—
—
57.6k
55556
-3.55
8
—
—
—
57.60k
0.00
3
—
—
—
115.2k
—
—
—
—
—
—
115.2k
0.00
1
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
FOSC = 64.000 MHz
Actual
Rate
%
Error
FOSC = 18.432 MHz
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
FOSC = 16.000 MHz
FOSC = 11.0592 MHz
Actual
Rate
%
Error
SPBRGHx
:SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
300
300
0.00
53332
300.0
0.00
15359
300.0
0.00
13332
300.0
0.00
9215
1200
1200
0.00
13332
1200
0.00
3839
1200.1
0.01
3332
1200
0.00
2303
2400
2400
0.00
6666
2400
0.00
1919
2399.5
-0.02
1666
2400
0.00
1151
9600
9598.1
-0.02
1666
9600
0.00
479
9592
-0.08
416
9600
0.00
287
10417
10417
0.00
1535
10425
0.08
441
10417
0.00
383
10433
0.16
264
19.2k
19.21k
0.04
832
19.20k
0.00
239
19.23k
0.16
207
19.20k
0.00
143
57.6k
57.55k
-0.08
277
57.60k
0.00
79
57.97k
0.64
68
57.60k
0.00
47
115.2k
115.11k
-0.08
138
115.2k
0.00
39
114.29k
-0.79
34
115.2k
0.00
23
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
FOSC = 8.000 MHz
Actual
Rate
FOSC = 4.000 MHz
%
Error
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
FOSC = 3.6864 MHz
%
Error
SPBRGHx:
SPBRGx
(decimal)
Actual
Rate
FOSC = 1.000 MHz
%
Error
SPBRGHx
:SPBRGx
(decimal)
Actual
Rate
%
Error
SPBRGHx:
SPBRGx
(decimal)
832
300
300.0
0.00
6666
300.0
0.01
3332
300.0
0.00
3071
300.1
0.04
1200
1200
-0.02
1666
1200
0.04
832
1200
0.00
767
1202
0.16
207
2400
2401
0.04
832
2398
0.08
416
2400
0.00
383
2404
0.16
103
9600
9615
0.16
207
9615
0.16
103
9600
0.00
95
9615
0.16
25
10417
10417
0.00
191
10417
0.00
95
10473
0.53
87
10417
0.00
23
19.2k
19.23k
0.16
103
19.23k
0.16
51
19.20k
0.00
47
19.23k
0.16
12
57.6k
57.14k
-0.79
34
58.82k
2.12
16
57.60k
0.00
15
—
—
—
115.2k
117.6k
2.12
16
111.1k
-3.55
8
115.2k
0.00
7
—
—
—
DS41412C-page 278
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.3.1
AUTO-BAUD DETECT
The EUSART module supports automatic detection
and calibration of the baud rate.
In the Auto-Baud Detect (ABD) mode, the clock to the
BRG is reversed. Rather than the BRG clocking the
incoming RXx signal, the RXx signal is timing the BRG.
The Baud Rate Generator is used to time the period of
a received 55h (ASCII “U”) which is the Sync character
for the LIN bus. The unique feature of this character is
that it has five rising edges including the Stop bit edge.
Setting the ABDEN bit of the BAUDCONx register
starts
the
auto-baud
calibration
sequence
(Figure 16.3.2). While the ABD sequence takes place,
the EUSART state machine is held in Idle. On the first
rising edge of the receive line, after the Start bit, the
SPBRGx begins counting up using the BRG counter
clock as shown in Table 16-6. The fifth rising edge will
occur on the RXx/DTx pin at the end of the eighth bit
period. At that time, an accumulated value totaling the
proper BRG period is left in the SPBRGHx:SPBRGx
register pair, the ABDEN bit is automatically cleared,
and the RCxIF interrupt flag is set. A read operation on
the RCREGx needs to be performed to clear the RCxIF
interrupt. RCREGx content should be discarded. When
calibrating for modes that do not use the SPBRGHx
register the user can verify that the SPBRGx register
did not overflow by checking for 00h in the SPBRGHx
register.
The BRG auto-baud clock is determined by the BRG16
and BRGH bits as shown in Table 16-6. During ABD,
both the SPBRGHx and SPBRGx registers are used as
a 16-bit counter, independent of the BRG16 bit setting.
While calibrating the baud rate period, the SPBRGHx
FIGURE 16-6:
Note 1: If the WUE bit is set with the ABDEN bit,
auto-baud detection will occur on the byte
following the Break character (see
Section 16.3.3
“Auto-Wake-up
on
Break”).
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.
3: During the auto-baud process, the autobaud counter starts counting at 1. Upon
completion of the auto-baud sequence, to
achieve maximum accuracy, subtract 1
from the SPBRGHx:SPBRGx register pair.
TABLE 16-6:
BRG COUNTER CLOCK
RATES
BRG16
BRGH
BRG Base
Clock
BRG ABD
Clock
0
0
FOSC/64
FOSC/512
0
1
FOSC/16
FOSC/128
1
0
FOSC/16
FOSC/128
1
1
FOSC/4
FOSC/32
Note:
During the ABD sequence, SPBRGx and
SPBRGHx registers are both used as a
16-bit counter, independent of BRG16
setting.
AUTOMATIC BAUD RATE CALIBRATION
XXXXh
BRG Value
and SPBRGx registers are clocked at 1/8th the BRG
base clock rate. The resulting byte measurement is the
average bit time when clocked at full speed.
RXx/DTx 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
RCIDL
RCxIF bit
(Interrupt)
Read
RCREGx
SPBRGx
XXh
1Ch
SPBRGHx
XXh
00h
Note 1:
The ABD sequence requires the EUSART module to be configured in Asynchronous mode.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 279
PIC18(L)F2X/4XK22
16.3.2
AUTO-BAUD OVERFLOW
16.3.3.1
During the course of automatic baud detection, the
ABDOVF bit of the BAUDCONx register will be set if the
baud rate counter overflows before the fifth rising edge
is detected on the RX pin. The ABDOVF bit indicates
that the counter has exceeded the maximum count that
can fit in the 16 bits of the SPBRGHx:SPBRGx register
pair. After the ABDOVF has been set, the counter continues to count until the fifth rising edge is detected on
the RXx/DTx pin. Upon detecting the fifth RXx/DTx
edge, the hardware will set the RCxIF interrupt flag and
clear the ABDEN bit of the BAUDCONx register. The
RCxIF flag can be subsequently cleared by reading the
RCREGx. The ABDOVF flag can be cleared by software directly.
To terminate the auto-baud process before the RCxIF
flag is set, clear the ABDEN bit then clear the ABDOVF
bit. The ABDOVF bit will remain set if the ABDEN bit is
not cleared first.
16.3.3
AUTO-WAKE-UP ON BREAK
During Sleep mode, all clocks to the EUSART are
suspended. Because of this, the Baud Rate Generator
is inactive and a proper character reception cannot be
performed. The Auto-Wake-up feature allows the
controller to wake-up due to activity on the RXx/DTx
line. This feature is available only in Asynchronous
mode.
The Auto-Wake-up feature is enabled by setting the
WUE bit of the BAUDCONx register. Once set, the
normal receive sequence on RXx/DTx is disabled, and
the EUSART remains in an Idle state, monitoring for a
wake-up event independent of the CPU mode. A wakeup event consists of a high-to-low transition on the
RXx/DTx line. (This coincides with the start of a Sync
Break or a wake-up signal character for the LIN
protocol.)
The EUSART module generates an RCxIF interrupt
coincident with the wake-up event. The interrupt is
generated synchronously to the Q clocks in normal CPU
operating modes (Figure 16-7), and asynchronously if
the device is in Sleep mode (Figure 16-8). The interrupt
condition is cleared by reading the RCREGx register.
Special Considerations
Break Character
To avoid character errors or character fragments during
a wake-up event, the wake-up character must be all
zeros.
When the wake-up is enabled the function works
independent of the low time on the data stream. If the
WUE bit is set and a valid non-zero character is
received, the low time from the Start bit to the first rising
edge will be interpreted as the wake-up event. The
remaining bits in the character will be received as a
fragmented character and subsequent characters can
result in framing or overrun errors.
Therefore, the initial character in the transmission must
be all ‘0’s. This must be 10 or more bit times, 13-bit
times recommended for LIN bus, or any number of bit
times for standard RS-232 devices.
Oscillator Startup Time
Oscillator start-up time must be considered, especially
in applications using oscillators with longer start-up
intervals (i.e., LP, XT or HS/PLL 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.
WUE Bit
The wake-up event causes a receive interrupt by
setting the RCxIF bit. The WUE bit is cleared by
hardware by a rising edge on RXx/DTx. The interrupt
condition is then cleared by software by reading the
RCREGx register and discarding its contents.
To ensure that no actual data is lost, check the RCIDL
bit to verify that a receive operation is not in process
before setting the WUE bit. If a receive operation is not
occurring, the WUE bit may then be set just prior to
entering the Sleep mode.
The WUE bit is automatically cleared by the low-to-high
transition on the RXx line at the end of the Break. This
signals to the user that the Break event is over. At this
point, the EUSART module is in Idle mode waiting to
receive the next character.
DS41412C-page 280
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 16-7:
AUTO-WAKE-UP BIT (WUE) TIMING DURING NORMAL OPERATION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 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 Q1 Q2 Q3 Q4
OSC1
Auto Cleared
Bit set by user
WUE bit
RXx/DTx Line
RCxIF
Note 1:
Cleared due to User Read of RCREGx
The EUSART remains in Idle while the WUE bit is set.
FIGURE 16-8:
AUTO-WAKE-UP BIT (WUE) TIMINGS DURING SLEEP
Q1Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1Q2 Q3 Q4
Q1
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4
OSC1
Auto Cleared
Bit Set by User
WUE bit
RXx/DTx Line
Note 1
RCxIF
Sleep Command Executed
Note 1:
2:
Sleep Ends
Cleared due to User Read of RCREGx
If the wake-up event requires long oscillator warm-up time, the automatic clearing of the WUE bit can occur while the stposc signal is
still active. This sequence should not depend on the presence of Q clocks.
The EUSART remains in Idle while the WUE bit is set.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 281
PIC18(L)F2X/4XK22
16.3.4
BREAK CHARACTER SEQUENCE
The EUSART module has the capability of sending the
special Break character sequences that are required by
the LIN bus standard. A Break character consists of a
Start bit, followed by 12 ‘0’ bits and a Stop bit.
To send a Break character, set the SENDB and TXEN
bits of the TXSTAx register. The Break character transmission is then initiated by a write to the TXREGx. The
value of data written to TXREGx 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 specification).
The TRMT bit of the TXSTAx register indicates when the
transmit operation is active or Idle, just as it does during
normal transmission. See Figure 16-9 for the timing of
the Break character sequence.
16.3.4.1
Break and Sync Transmit Sequence
The following sequence will start 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.
1.
2.
3.
4.
5.
Configure the EUSART for the desired mode.
Set the TXEN and SENDB bits to enable the
Break sequence.
Load the TXREGx with a dummy character to
initiate transmission (the value is ignored).
Write ‘55h’ to TXREGx to load the Sync character into the transmit FIFO buffer.
After the Break has been sent, the SENDB bit is
reset by hardware and the Sync character is
then transmitted.
FIGURE 16-9:
Write to TXREGx
When the TXREGx becomes empty, as indicated by
the TXxIF, the next data byte can be written to
TXREGx.
16.3.5
RECEIVING A BREAK CHARACTER
The Enhanced EUSART module can receive a Break
character in two ways.
The first method to detect a Break character uses the
FERR bit of the RCSTAx register and the Received
data as indicated by RCREGx. The Baud Rate
Generator is assumed to have been initialized to the
expected baud rate.
A Break character has been received when;
• RCxIF bit is set
• FERR bit is set
• RCREGx = 00h
The second method uses the Auto-Wake-up feature
described in Section 16.3.3 “Auto-Wake-up on
Break”. By enabling this feature, the EUSART will
sample the next two transitions on RXx/DTx, cause an
RCxIF 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 Detect feature.
For both methods, the user can set the ABDEN bit of
the BAUDCONx register before placing the EUSART in
Sleep mode.
SEND BREAK CHARACTER SEQUENCE
Dummy Write
BRG Output
(Shift Clock)
TXx/CKx (pin)
Start bit
bit 0
bit 1
bit 11
Stop bit
Break
TXxIF bit
(Transmit
interrupt Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
SENDB
(send Break
control bit)
DS41412C-page 282
SENDB Sampled Here
Preliminary
Auto Cleared
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
16.4
EUSART Synchronous Mode
16.4.1.2
Synchronous serial communications are typically used
in systems with a single master and one or more
slaves. The master device contains the necessary
circuitry for baud rate generation and supplies the clock
for all devices in the system. Slave devices can take
advantage of the master clock by eliminating the
internal clock generation circuitry.
There are two signal lines in Synchronous mode: a
bidirectional data line and a clock line. Slaves use the
external clock supplied by the master to shift the serial
data into and out of their respective receive and
transmit shift registers. Since the data line is
bidirectional, synchronous operation is half-duplex
only. Half-duplex refers to the fact that master and
slave devices can receive and transmit data but not
both simultaneously. The EUSART can operate as
either a master or slave device.
Start and Stop bits are not used in synchronous
transmissions.
16.4.1
SYNCHRONOUS MASTER MODE
The following bits are used to configure the EUSART
for Synchronous Master operation:
•
•
•
•
•
SYNC = 1
CSRC = 1
SREN = 0 (for transmit); SREN = 1 (for receive)
CREN = 0 (for transmit); CREN = 1 (for receive)
SPEN = 1
Clock Polarity
A clock polarity option is provided for Microwire
compatibility. Clock polarity is selected with the CKTXP
bit of the BAUDCONx register. Setting the CKTXP bit
sets the clock Idle state as high. When the CKTXP bit
is set, the data changes on the falling edge of each
clock and is sampled on the rising edge of each clock.
Clearing the CKTXP bit sets the Idle state as low. When
the CKTXP bit is cleared, the data changes on the
rising edge of each clock and is sampled on the falling
edge of each clock.
16.4.1.3
Synchronous Master Transmission
Data is transferred out of the device on the RXx/DTx
pin. The RXx/DTx and TXx/CKx pin output drivers are
automatically enabled when the EUSART is configured
for synchronous master transmit operation.
A transmission is initiated by writing a character to the
TXREGx register. If the TSR still contains all or part of
a previous character the new character data is held in
the TXREGx until the last bit of the previous character
has been transmitted. If this is the first character, or the
previous character has been completely flushed from
the TSR, the data in the TXREGx is immediately transferred to the TSR. The transmission of the character
commences immediately following the transfer of the
data to the TSR from the TXREGx.
Each data bit changes on the leading edge of the
master clock and remains valid until the subsequent
leading clock edge.
Setting the SYNC bit of the TXSTAx register configures
the device for synchronous operation. Setting the CSRC
bit of the TXSTAx register configures the device as a
master. Clearing the SREN and CREN bits of the
RCSTAx register ensures that the device is in the
Transmit mode, otherwise the device will be configured
to receive. Setting the SPEN bit of the RCSTAx register
enables the EUSART. If the RXx/DTx or TXx/CKx pins
are shared with an analog peripheral the analog I/O
functions must be disabled by clearing the corresponding
ANSEL bits.
Note:
16.4.1.4
The TSR register is not mapped in data
memory, so it is not available to the user.
Data Polarity
The polarity of the transmit and receive data can be
controlled with the DTRXP bit of the BAUDCONx
register. The default state of this bit is ‘0’ which selects
high true transmit and receive data. Setting the DTRXP
bit to ‘1’ will invert the data resulting in low true transmit
and receive data.
The TRIS bits corresponding to the RXx/DTx and
TXx/CKx pins should be set.
16.4.1.1
Master Clock
Synchronous data transfers use a separate clock line,
which is synchronous with the data. A device configured
as a master transmits the clock on the TXx/CKx line. The
TXx/CKx pin output driver is automatically enabled when
the EUSART is configured for synchronous transmit or
receive operation. Serial data bits change on the leading
edge to ensure they are valid at the trailing edge of each
clock. One clock cycle is generated for each data bit.
Only as many clock cycles are generated as there are
data bits.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 283
PIC18(L)F2X/4XK22
16.4.1.5
1.
2.
3.
Synchronous Master Transmission
Set-up:
4.
Initialize the SPBRGHx, SPBRGx register pair
and the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 16.3 “EUSART
Baud Rate Generator (BRG)”).
Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC. Set the
TRIS bits corresponding to the RXx/DTx and
TXx/CKx I/O pins.
5.
6.
7.
FIGURE 16-10:
8.
9.
Disable Receive mode by clearing bits SREN
and CREN.
Enable Transmit mode by setting the TXEN bit.
If 9-bit transmission is desired, set the TX9 bit.
If interrupts are desired, set the TXxIE, GIE/
GIEH and PEIE/GIEL interrupt enable bits.
If 9-bit transmission is selected, the ninth bit
should be loaded in the TX9D bit.
Start transmission by loading data to the
TXREGx register.
SYNCHRONOUS TRANSMISSION
RXx/DTx
pin
bit 0
bit 1
Word 1
bit 2
bit 7
bit 0
bit 1
Word 2
bit 7
TXx/CKx pin
(SCKP = 0)
TXx/CKx pin
(SCKP = 1)
Write to
TXREGx Reg
Write Word 1
Write Word 2
TXxIF bit
(Interrupt Flag)
TRMT bit
TXEN bit
Note:
‘1’
‘1’
Sync Master mode, SPBRGx = 0, continuous transmission of two 8-bit words.
FIGURE 16-11:
SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RXx/DTx pin
bit 0
bit 1
bit 2
bit 6
bit 7
TXx/CKx pin
Write to
TXREGx reg
TXxIF bit
TRMT bit
TXEN bit
DS41412C-page 284
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 16-7:
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
CCP1IP
TMR2IP
TMR1IP
127
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
TMR5GIP TMR3GIP TMR1GIP
CCP1IE
TMR2IE
TMR1IE
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
TMR5GIE TMR3GIE TMR1GIE
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF TMR3GIF TMR1GIF
PMD0
TMR3MD TMR2MD TMR1MD
CCP1IF
TMR2IF
TMR1IF
129
123
125
118
120
UART2MD
UART1MD
TMR6MD
TMR5MD
TMR4MD
RCSTA1
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
56
RCSTA2
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
TRISB(2)
TRISB7
—
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
CSRC
TX9
TXEN
BRGH
TRMT
TX9D
272
TXREG1
TXSTA1
EUSART1 Transmit Register
TXREG2
TXSTA2
Note
SENDB
—
EUSART2 Transmit Register
CSRC
Legend:
SYNC
TX9
TXEN
SYNC
SENDB
—
BRGH
TRMT
TX9D
272
— = unimplemented locations, read as ‘0’. Shaded bits are not used for synchronous master transmission.
1: PIC18(L)F4XK22 devices.
2: PIC18(L)F2XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 285
PIC18(L)F2X/4XK22
16.4.1.6
Synchronous Master Reception
Data is received at the RXx/DTx pin. The RXx/DTx pin
output driver must be disabled by setting the
corresponding TRIS bits when the EUSART is
configured for synchronous master receive operation.
In Synchronous mode, reception is enabled by setting
either the Single Receive Enable bit (SREN of the
RCSTAx register) or the Continuous Receive Enable
bit (CREN of the RCSTAx register).
When SREN is set and CREN is clear, only as many
clock cycles are generated as there are data bits in a
single character. The SREN bit is automatically cleared
at the completion of one character. When CREN is set,
clocks are continuously generated until CREN is
cleared. If CREN is cleared in the middle of a character
the CK clock stops immediately and the partial character is discarded. If SREN and CREN are both set, then
SREN is cleared at the completion of the first character
and CREN takes precedence.
To initiate reception, set either SREN or CREN. Data is
sampled at the RXx/DTx pin on the trailing edge of the
TXx/CKx clock pin and is shifted into the Receive Shift
Register (RSR). When a complete character is
received into the RSR, the RCxIF bit is set and the
character is automatically transferred to the two
character receive FIFO. The Least Significant eight bits
of the top character in the receive FIFO are available in
RCREGx. The RCxIF bit remains set as long as there
are un-read characters in the receive FIFO.
16.4.1.7
Slave Clock
Synchronous data transfers use a separate clock line,
which is synchronous with the data. A device configured
as a slave receives the clock on the TXx/CKx line. The
TXx/CKx pin output driver must be disabled by setting
the associated TRIS bit when the device is configured
for synchronous slave transmit or receive operation.
Serial data bits change on the leading edge to ensure
they are valid at the trailing edge of each clock. One data
bit is transferred for each clock cycle. Only as many
clock cycles should be received as there are data bits.
16.4.1.8
Receive Overrun Error
The receive FIFO buffer can hold two characters. An
overrun error will be generated if a third character, in its
entirety, is received before RCREGx is read to access
the FIFO. When this happens the OERR bit of the
RCSTAx register is set. Previous data in the FIFO will
not be overwritten. The two characters in the FIFO
buffer can be read, however, no additional characters
will be received until the error is cleared. The OERR bit
can only be cleared by clearing the overrun condition.
If the overrun error occurred when the SREN bit is set
and CREN is clear then the error is cleared by reading
RCREGx.
DS41412C-page 286
If the overrun occurred when the CREN bit is set then
the error condition is cleared by either clearing the
CREN bit of the RCSTAx register or by clearing the
SPEN bit which resets the EUSART.
16.4.1.9
Receiving 9-bit Characters
The EUSART supports 9-bit character reception. When
the RX9 bit of the RCSTAx register is set the EUSART
will shift 9-bits into the RSR for each character
received. The RX9D bit of the RCSTAx register is the
ninth, and Most Significant, data bit of the top unread
character in the receive FIFO. When reading 9-bit data
from the receive FIFO buffer, the RX9D data bit must
be read before reading the 8 Least Significant bits from
the RCREGx.
16.4.1.10
Synchronous Master Reception Setup:
1.
Initialize the SPBRGHx, SPBRGx register pair
for the appropriate baud rate. Set or clear the
BRGH and BRG16 bits, as required, to achieve
the desired baud rate.
2. Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
3. Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC. Disable
RXx/DTx and TXx/CKx output drivers by setting
the corresponding TRIS bits.
4. Ensure bits CREN and SREN are clear.
5. If using interrupts, set the GIE/GIEH and PEIE/
GIEL bits of the INTCON register and set
RCxIE.
6. If 9-bit reception is desired, set bit RX9.
7. Start reception by setting the SREN bit or for
continuous reception, set the CREN bit.
8. Interrupt flag bit RCxIF will be set when reception of a character is complete. An interrupt will
be generated if the enable bit RCxIE was set.
9. Read the RCSTAx register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
10. Read the 8-bit received data by reading the
RCREGx register.
11. If an overrun error occurs, clear the error by
either clearing the CREN bit of the RCSTAx
register or by clearing the SPEN bit which resets
the EUSART.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 16-12:
SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
RXx/DTx
pin
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
bit 6
bit 7
TXx/CKx pin
(SCKP = 0)
TXx/CKx pin
(SCKP = 1)
Write to
bit SREN
SREN bit
CREN bit ‘0’
‘0’
RCxIF bit
(Interrupt)
Read
RCREGx
Note:
Timing diagram demonstrates Sync Master mode with bit SREN = 1 and bit BRGH = 0.
TABLE 16-8:
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP TMR1GIP
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
OERR
RX9D
273
PIR3
PMD0
UART2MD UART1MD TMR6MD TMR5MD
RCREG1
RCSTA1
TMR1IE
TMR3GIE TMR1GIE
EUSART1 Receive Register
SPEN
RX9
SREN
RCREG2
RCSTA2
TMR2IE
129
CREN
ADDEN
—
FERR
EUSART2 Receive Register
SPEN
RX9
SREN
CREN
ADDEN
123
125
—
FERR
OERR
RX9D
273
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
—
TXSTA1
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TXSTA2
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
Legend:
— = unimplemented locations, read as ‘0’. Shaded bits are not used for synchronous master reception.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 287
PIC18(L)F2X/4XK22
16.4.2
SYNCHRONOUS SLAVE MODE
The following bits are used to configure the EUSART
for Synchronous slave operation:
•
•
•
•
•
SYNC = 1
CSRC = 0
SREN = 0 (for transmit); SREN = 1 (for receive)
CREN = 0 (for transmit); CREN = 1 (for receive)
SPEN = 1
1.
2.
3.
4.
Setting the SYNC bit of the TXSTAx register configures
the device for synchronous operation. Clearing the
CSRC bit of the TXSTAx register configures the device as
a slave. Clearing the SREN and CREN bits of the
RCSTAx register ensures that the device is in the
Transmit mode, otherwise the device will be configured to
receive. Setting the SPEN bit of the RCSTAx register
enables the EUSART. If the RXx/DTx or TXx/CKx pins
are shared with an analog peripheral the analog I/O
functions must be disabled by clearing the corresponding
ANSEL bits.
RXx/DTx and TXx/CKx pin output drivers must be
disabled by setting the corresponding TRIS bits.
16.4.2.1
If two words are written to the TXREGx and then the
SLEEP instruction is executed, the following will occur:
EUSART Synchronous Slave
Transmit
The operation of the Synchronous Master and Slave
modes
are
identical
(see
Section 16.4.1.3
“Synchronous Master Transmission”), except in the
case of the Sleep mode.
5.
16.4.2.2
1.
2.
3.
4.
5.
6.
7.
8.
DS41412C-page 288
The first character will immediately transfer to
the TSR register and transmit.
The second word will remain in TXREGx
register.
The TXxIF bit will not be set.
After the first character has been shifted out of
TSR, the TXREGx register will transfer the
second character to the TSR and the TXxIF bit
will now be set.
If the PEIE/GIEL and TXxIE bits are set, the
interrupt will wake the device from Sleep and
execute the next instruction. If the GIE/GIEH bit
is also set, the program will call the Interrupt
Service Routine.
Preliminary
Synchronous Slave Transmission
Set-up:
Set the SYNC and SPEN bits and clear the
CSRC bit.
Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
Clear the CREN and SREN bits.
If using interrupts, ensure that the GIE/GIEH
and PEIE/GIEL bits of the INTCON register are
set and set the TXxIE bit.
If 9-bit transmission is desired, set the TX9 bit.
Enable transmission by setting the TXEN bit.
If 9-bit transmission is selected, insert the Most
Significant bit into the TX9D bit.
Start transmission by writing the Least
Significant 8 bits to the TXREGx register.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 16-9:
REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
125
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
PMD0
TMR6MD TMR5MD TMR4MD
UART2MD
UART1MD
RCSTA1
SPEN
RX9
RCSTA2
SPEN
RX9
TMR3MD
TMR2MD
TMR1MD
56
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
SREN
CREN
ADDEN
FERR
OERR
RX9D
273
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
TRISB(2)
TRISB7
—
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
CSRC
TX9
TXEN
TRMT
TX9D
272
TXREG1
TXSTA1
EUSART1 Transmit Register
TXREG2
TXSTA2
SYNC
SENDB
—
BRGH
EUSART2 Transmit Register
CSRC
TX9
TXEN
SYNC
SENDB
—
BRGH
TRMT
TX9D
272
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used for synchronous slave transmission.
Note
1: PIC18(L)F4XK22 devices.
2: PIC18(L)F2XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 289
PIC18(L)F2X/4XK22
16.4.2.3
EUSART Synchronous Slave
Reception
16.4.2.4
The operation of the Synchronous Master and Slave
modes is identical (Section 16.4.1.6 “Synchronous
Master Reception”), with the following exceptions:
• Sleep
• CREN bit is always set, therefore the receiver is
never Idle
• SREN bit, which is a “don't care” in Slave mode
1.
2.
3.
A character may be received while in Sleep mode by
setting the CREN bit prior to entering Sleep. Once the
word is received, the RSR register will transfer the data
to the RCREGx register. If the RCxIE enable bit is set,
the interrupt generated will wake the device from Sleep
and execute the next instruction. If the GIE/GIEH bit is
also set, the program will branch to the interrupt vector.
4.
5.
6.
7.
8.
9.
Synchronous Slave Reception Setup:
Set the SYNC and SPEN bits and clear the
CSRC bit.
Set the RXx/DTx and TXx/CKx TRIS controls to
‘1’.
If using interrupts, ensure that the GIE/GIEH
and PEIE/GIEL bits of the INTCON register are
set and set the RCxIE bit.
If 9-bit reception is desired, set the RX9 bit.
Set the CREN bit to enable reception.
The RCxIF bit will be set when reception is
complete. An interrupt will be generated if the
RCxIE bit was set.
If 9-bit mode is enabled, retrieve the Most
Significant bit from the RX9D bit of the RCSTAx
register.
Retrieve the 8 Least Significant bits from the
receive FIFO by reading the RCREGx register.
If an overrun error occurs, clear the error by
either clearing the CREN bit of the RCSTAx
register or by clearing the SPEN bit which resets
the EUSART.
TABLE 16-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
BAUDCON1
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
274
274
BAUDCON2
ABDOVF
RCIDL
DTRXP
CKTXP
BRG16
—
WUE
ABDEN
INTCON
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
TMR4MD
TMR3MD
TMR2MD
TMR1MD
56
FERR
OERR
RX9D
273
FERR
OERR
RX9D
273
PMD0
UART2MD UART1MD TMR6MD TMR5MD
RCREG1
RCSTA1
EUSART1 Receive Register
SPEN
RX9
SREN
SPEN
RX9
SREN
RCREG2
RCSTA2
CREN
ADDEN
—
EUSART2 Receive Register
CREN
ADDEN
—
SPBRG1
EUSART1 Baud Rate Generator, Low Byte
—
SPBRGH1
EUSART1 Baud Rate Generator, High Byte
—
SPBRG2
EUSART2 Baud Rate Generator, Low Byte
—
SPBRGH2
EUSART2 Baud Rate Generator, High Byte
—
TXSTA1
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
TXSTA2
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
272
Legend:
— = unimplemented locations, read as ‘0’. Shaded bits are not used for synchronous slave reception.
DS41412C-page 290
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
17.0
ANALOG-TO-DIGITAL
CONVERTER (ADC) MODULE
The ADC voltage reference is software selectable to
either VDD or a voltage applied to the external reference
pins.
The Analog-to-Digital Converter (ADC) allows
conversion of an analog input signal to a 10-bit binary
representation of that signal. This device uses analog
inputs, which are multiplexed into a single sample and
hold circuit. The output of the sample and hold is
connected to the input of the converter. The converter
generates a 10-bit binary result via successive
approximation and stores the conversion result into the
ADC result registers (ADRESL and ADRESH).
FIGURE 17-1:
The ADC can generate an interrupt upon completion of
a conversion. This interrupt can be used to wake-up the
device from Sleep.
Figure 17-1 shows the block diagram of the ADC.
ADC BLOCK DIAGRAM
5
FVR BUF2
11111
CTMU
11110
Reserved
11101
AN28(1)
AN27(1)
CHS<4:0>
11100
11011
ADCMD
AN5(1)
AN4
AN3
AN2
AN1
AN0
ADON
00101
10-Bit ADC
00100
GO/DONE
10
00011
00010
ADFM
00001
0 = Left Justify
1 = Right Justify
00000
10
2
PVCFG<1:0>
ADRESH
AVDD
VREF+/AN3
01
FVR BUF2
10
Reserved
11
2
AVSS
VREF-/AN2
ADRESL
00
NVCFG<1:0>
00
01
Reserved
10
Reserved
11
Note: Additional ADC channels AN5-AN7 and AN20-AN27 are only available on PIC18(L)F4XK22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 291
PIC18(L)F2X/4XK22
17.1
ADC Configuration
17.1.3
When configuring and using the ADC the following
functions must be considered:
•
•
•
•
•
•
Port configuration
Channel selection
ADC voltage reference selection
ADC conversion clock source
Interrupt control
Results formatting
17.1.1
• VDD
• the fixed voltage reference (FVR BUF2)
• an external voltage source (VREF+)
The negative voltage reference can be:
PORT CONFIGURATION
The A/D operation is independent of the state of the
ANSx bits and the TRIS bits.
Note 1: When reading the PORT register, all pins
with their corresponding ANSx bit set
read as cleared (a low level). However,
analog conversion of pins configured as
digital inputs (ANSx bit cleared and
TRISx bit set) will be accurately
converted.
2: Analog levels on any pin with the corresponding ANSx bit cleared may cause the
digital input buffer to consume current out
of the device’s specification limits.
3: The PBADEN bit in Configuration
Register 3H configures PORTB pins to
reset as analog or digital pins by
controlling how the bits in ANSELB are
reset.
CHANNEL SELECTION
The CHS bits of the ADCON0 register determine which
channel is connected to the sample and hold circuit.
When changing channels, a delay is required before
starting the next conversion. Refer to Section 17.2
“ADC Operation” for more information.
DS41412C-page 292
The PVCFG<1:0> and NVCFG<1:0> bits of the
ADCON1 register provide independent control of the
positive and negative voltage references.
The positive voltage reference can be:
The ANSELx and TRISx registers configure the A/D
port pins. Any port pin needed as an analog input
should have its corresponding ANSx bit set to disable
the digital input buffer and TRISx bit set to disable the
digital output driver. If the TRISx bit is cleared, the
digital output level (VOH or VOL) will be converted.
17.1.2
ADC VOLTAGE REFERENCE
• VSS
• an external voltage source (VREF-)
17.1.4
SELECTING AND CONFIGURING
ACQUISITION TIME
The ADCON2 register allows the user to select an
acquisition time that occurs each time the GO/DONE
bit is set.
Acquisition time is set with the ACQT<2:0> bits of the
ADCON2 register. Acquisition delays cover a range of
2 to 20 TAD. 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 is no need to wait for an acquisition time between
selecting a channel and setting the GO/DONE bit.
Manual
acquisition
is
selected
when
ACQT<2:0> = 000. 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 option is
also the default Reset state of the ACQT<2:0> bits and
is compatible with devices that do not offer
programmable acquisition times.
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. When an acquisition time is programmed, there
is no indication of when the acquisition time ends and
the conversion begins.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
17.1.5
CONVERSION CLOCK
17.1.6
The source of the conversion clock is software
selectable via the ADCS bits of the ADCON2 register.
There are seven possible clock options:
•
•
•
•
•
•
•
The ADC module allows for the ability to generate an
interrupt upon completion of an Analog-to-Digital
Conversion. The ADC interrupt enable is the ADIE bit
in the PIE1 register and the interrupt priority is the ADIP
bit in the IPR1 register. The ADC interrupt flag is the
ADIF bit in the PIR1 register. The ADIF bit must be
cleared by software.
FOSC/2
FOSC/4
FOSC/8
FOSC/16
FOSC/32
FOSC/64
FRC (dedicated internal oscillator)
Note:
For correct conversion, the appropriate TAD specification
must be met. See A/D conversion requirements in
Table 27-24 for more information. Table gives examples
of appropriate ADC clock selections.
Unless using the FRC, any changes in the
system clock frequency will change the
ADC clock frequency, which may
adversely affect the ADC result.
TABLE 17-1:
The ADIF bit is set at the completion of
every conversion, regardless of whether
or not the ADC interrupt is enabled.
This interrupt can be generated while the device is
operating or while in Sleep. If the device is in Sleep, the
interrupt will wake-up the device. Upon waking from
Sleep, the next instruction following the SLEEP
instruction is always executed. If the user is attempting
to wake-up from Sleep and resume in-line code
execution, the global interrupt must be disabled. If the
global interrupt is enabled, execution will switch to the
Interrupt Service Routine.
The time to complete one bit conversion is defined as
TAD. One full 10-bit conversion requires 11 TAD periods
as shown in Figure 17-3.
Note:
INTERRUPTS
ADC CLOCK PERIOD (TAD) VS. DEVICE OPERATING FREQUENCIES
ADC Clock Period (TAD)
ADC Clock Source
ADCS<2:0>
Device Frequency (FOSC)
64 MHz
ns(2)
16 MHz
ns(2)
4 MHz
ns(2)
1 MHz
2.0 s
FOSC/2
000
31.25
FOSC/4
100
62.5 ns(2)
250 ns(2)
1.0 s
4.0 s(3)
FOSC/8
001
400 ns(2)
500 ns(2)
2.0 s
8.0 s(3)
FOSC/16
101
250
ns(2)
FOSC/32
010
500 ns(2)
FOSC/64
110
1.0 s
FRC
x11
1-4 s(1,4)
Legend:
Note 1:
2:
3:
4:
125
500
1.0 s
4.0
s(3)
16.0 s(3)
2.0 s
8.0 s(3)
32.0 s(3)
s(3)
64.0 s(3)
1-4 s(1,4)
1-4 s(1,4)
4.0
s(3)
1-4 s(1,4)
16.0
Shaded cells are outside of recommended range.
The FRC source has a typical TAD time of 1.7 s.
These values violate the minimum required TAD time.
For faster conversion times, the selection of another clock source is recommended.
When the device frequency is greater than 1 MHz, the FRC clock source is only recommended if the
conversion will be performed during Sleep.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 293
PIC18(L)F2X/4XK22
17.1.7
RESULT FORMATTING
The 10-bit A/D conversion result can be supplied in two
formats, left justified or right justified. The ADFM bit of
the ADCON2 register controls the output format.
Figure 17-2 shows the two output formats.
FIGURE 17-2:
10-BIT A/D CONVERSION RESULT FORMAT
ADRESH
(ADFM = 0)
ADRESL
MSB
LSB
bit 7
bit 0
bit 7
10-bit A/D Result
Unimplemented: Read as ‘0’
MSB
(ADFM = 1)
bit 7
LSB
bit 0
Unimplemented: Read as ‘0’
DS41412C-page 294
bit 0
bit 7
bit 0
10-bit A/D Result
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
17.2
ADC Operation
17.2.1
Figure 17-3 shows the operation of the A/D converter
after the GO 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.
STARTING A CONVERSION
To enable the ADC module, the ADON bit of the
ADCON0 register must be set to a ‘1’. Setting the GO/
DONE bit of the ADCON0 register to a ‘1’ will, depending on the ACQT bits of the ADCON2 register, either
immediately start the Analog-to-Digital conversion or
start an acquisition delay followed by the Analog-toDigital conversion.
FIGURE 17-3:
Figure 17-4 shows the operation of the A/D converter
after the GO bit has been set and the ACQT<2:0> bits
are set to ‘010’ which selects a 4 TAD acquisition time
before the conversion starts.
Note:
The GO/DONE bit should not be set in the
same instruction that turns on the ADC.
Refer to Section 17.2.10 “A/D Conversion Procedure”.
A/D CONVERSION TAD CYCLES (ACQT<2:0> = 000, TACQ = 0)
TCY - TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11 2 TAD
b4
b1
b0
b6
b7
b2
b9
b8
b3
b5
Conversion starts
Discharge
Holding capacitor is disconnected from analog input (typically 100 ns)
Set GO bit
On the following cycle:
ADRESH:ADRESL is loaded, GO 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 17-4:
TAD Cycles
TACQT Cycles
1
2
3
Automatic
Acquisition
Time
4
1
2
3
4
5
b9
b8
b7
b6
6
b5
7
8
9
10
11
b4
b3
b2
b1
b0
Conversion starts
(Holding capacitor is disconnected from analog input)
Set GO bit
(Holding capacitor continues
acquiring input)
 2010 Microchip Technology Inc.
2 TAD
Discharge
On the following cycle:
ADRESH:ADRESL is loaded, GO bit is cleared,
ADIF bit is set, holding capacitor is connected to analog input.
Preliminary
DS41412C-page 295
PIC18(L)F2X/4XK22
17.2.2
COMPLETION OF A CONVERSION
When the conversion is complete, the ADC module will:
• Clear the GO/DONE bit
• Set the ADIF flag bit
• Update the ADRESH:ADRESL registers with new
conversion result
17.2.3
DISCHARGE
The discharge phase is used to initialize the value of
the capacitor array. The array is discharged after every
sample. This feature helps to optimize the unity-gain
amplifier, as the circuit always needs to charge the
capacitor array, rather than charge/discharge based on
previous measure values.
17.2.4
TERMINATING A CONVERSION
If a conversion must be terminated before completion,
the GO/DONE bit can be cleared by software. The
ADRESH:ADRESL registers will not be updated with
the partially complete Analog-to-Digital conversion
sample. Instead, the ADRESH:ADRESL register pair
will retain the value of the previous conversion.
Note:
17.2.5
A device Reset forces all registers to their
Reset state. Thus, the ADC module is
turned off and any pending conversion is
terminated.
DELAY BETWEEN CONVERSIONS
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, the currently selected
channel is reconnected to the charge holding capacitor
commencing the next acquisition.
17.2.6
ADC OPERATION IN POWERMANAGED 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.
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 clock source to be used in that
mode. After entering the mode, an A/D acquisition or
conversion may be started. Once started, the device
should continue to be clocked by the same clock
source until the conversion has been completed.
If desired, the device may be placed into the
corresponding Idle mode during the conversion. If the
device clock frequency is less than 1 MHz, the A/D FRC
clock source should be selected.
DS41412C-page 296
17.2.7
ADC OPERATION DURING SLEEP
The ADC module can operate during Sleep. This
requires the ADC clock source to be set to the FRC
option. When the FRC clock source is selected, the
ADC waits one additional instruction before starting the
conversion. This allows the SLEEP instruction to be
executed, which can reduce system noise during the
conversion. If the ADC interrupt is enabled, the device
will wake-up from Sleep when the conversion
completes. If the ADC interrupt is disabled, the ADC
module is turned off after the conversion completes,
although the ADON bit remains set.
When the ADC clock source is something other than
FRC, a SLEEP instruction causes the present
conversion to be aborted and the ADC module is
turned off, although the ADON bit remains set.
17.2.8
SPECIAL EVENT TRIGGER
Two Special Event Triggers are available to start an A/D
conversion: CTMU and CCP5. The Special Event
Trigger source is selected using the TRIGSEL bit in
ADCON1.
When TRIGSEL = 0, the CCP5 module is selected as
the Special Event Trigger source. To enable the Special
Event Trigger in the CCP module, set CCP5M<3:0> =
1011, in the CCP5CON register.
When TRIGSEL = 1, the CTMU module is selected.
The CTMU module requires that the CTTRIG bit in
CTMUCONH is set to enable the Special Event Trigger.
In addition to TRIGSEL bit, the following steps are
required to start an A/D conversion:
• The A/D module must be enabled (ADON = 1)
• The appropriate analog input channel selected
• The minimum acquisition period set one of these
ways:
- Timing provided by the user
- Selection made of an appropriate TACQ time
With these conditions met, the trigger sets the GO/DONE
bit and the A/D acquisition starts.
If the A/D module is not enabled (ADON = 0), the
module ignores the Special Event Trigger.
17.2.9
PERIPHERAL MODULE DISABLE
When a peripheral module is not used or inactive, the
module can be disabled by setting the Module Disable
bit in the PMD registers. This will reduce power
consumption to an absolute minimum. Setting the PMD
bits holds the module in Reset and disconnects the
module’s clock source. The Module Disable bit for the
ADC module is ADCMD in the PMD2 Register. See
Section 3.0 “Power-Managed Modes” for more
information.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
17.2.10
A/D CONVERSION PROCEDURE
EXAMPLE 17-1:
This is an example procedure for using the ADC to
perform an Analog-to-Digital conversion:
1.
2.
3.
4.
5.
6.
7.
8.
Configure Port:
• Disable pin output driver (See TRIS register)
• Configure pin as analog
Configure the ADC module:
• Select ADC conversion clock
• Configure voltage reference
• Select ADC input channel
• Select result format
• Select acquisition delay
• Turn on ADC module
Configure ADC interrupt (optional):
• Clear ADC interrupt flag
• Enable ADC interrupt
• Enable peripheral interrupt
• Enable global interrupt(1)
Wait the required acquisition time(2).
Start conversion by setting the GO/DONE bit.
Wait for ADC conversion to complete by one of
the following:
• Polling the GO/DONE bit
• Waiting for the ADC interrupt (interrupts
enabled)
Read ADC Result
Clear the ADC interrupt flag (required if interrupt
is enabled).
A/D CONVERSION
;This code block configures the ADC
;for polling, Vdd and Vss as reference, Frc
clock and AN0 input.
;
;Conversion start & polling for completion
; are included.
;
MOVLW
B’10101111’ ;right justify, Frc,
MOVWF
ADCON2
; & 12 TAD ACQ time
MOVLW
B’00000000’ ;ADC ref = Vdd,Vss
MOVWF
ADCON1
;
BSF
TRISA,0
;Set RA0 to input
BSF
ANSEL,0
;Set RA0 to analog
MOVLW
B’00000001’ ;AN0, ADC on
MOVWF
ADCON0
;
BSF
ADCON0,GO
;Start conversion
ADCPoll:
BTFSC
ADCON0,GO
;Is conversion done?
BRA
ADCPoll
;No, test again
; Result is complete - store 2 MSbits in
; RESULTHI and 8 LSbits in RESULTLO
MOVFF
ADRESH,RESULTHI
MOVFF
ADRESL,RESULTLO
Note 1: The global interrupt can be disabled if the
user is attempting to wake-up from Sleep
and resume in-line code execution.
2: Software delay required if ACQT bits are
set to zero delay. See Section 17.3 “A/D
Acquisition Requirements”.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 297
PIC18(L)F2X/4XK22
17.2.11
ADC REGISTER DEFINITIONS
The following registers are used to control the
operation of the ADC.
Note:
Analog pin control is determined by the
ANSELx registers (see Register 10-2)
REGISTER 17-1:
U-0
ADCON0: A/D CONTROL REGISTER 0
R/W-0
R/W-0
—
R/W-0
R/W-0
R/W-0
CHS<4:0>
R/W-0
R/W-0
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
x = Bit is unknown
bit 7
Unimplemented: Read as ‘0’
bit 6-2
CHS<4:0>: Analog Channel Select bits
00000 = AN0
00001 = AN1
00010 = AN2
00011 = AN3
00100 = AN4
00101 = AN5(1)
00110 = AN6(1)
00111 = AN7(1)
01000 = AN8
01001 = AN9
01010 = AN10
01011 = AN11
01100 = AN12
01101 = AN13
01110 = AN14
01111 = AN15
10000 = AN16
10001 = AN17
10010 = AN18
10011 = AN19
10100 = AN20(1)
10101 = AN21(1)
10110 = AN22(1)
10111 = AN23(1)
11000 = AN24(1)
11001 = AN25(1)
11010 = AN26(1)
11011 = AN27(1)
11100 = Reserved
11101 = CTMU
11110 = DAC
11111 = FVR BUF2 (1.024V/2.048V/2.096V Volt Fixed Voltage Reference)(2)
bit 1
GO/DONE: A/D Conversion Status bit
1 = A/D conversion cycle in progress. Setting this bit starts an A/D conversion cycle.
This bit is automatically cleared by hardware when the A/D conversion has completed.
0 = A/D conversion completed/not in progress
DS41412C-page 298
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 17-1:
bit 0
Note 1:
2:
ADCON0: A/D CONTROL REGISTER 0 (CONTINUED)
ADON: ADC Enable bit
1 = ADC is enabled
0 = ADC is disabled and consumes no operating current
Available on PIC18(L)F4XK22 devices only.
Allow greater than 15 s acquisition time when measuring the Fixed Voltage Reference.
REGISTER 17-2:
ADCON1: A/D CONTROL REGISTER 1
R/W-0
U-0
U-0
U-0
TRIGSEL
—
—
—
R/W-0
R/W-0
R/W-0
PVCFG<1:0>
R/W-0
NVCFG<1:0>
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
x = Bit is unknown
TRIGSEL: Special Trigger Select bit
1 = Selects the special trigger from CTMU
0 = Selects the special trigger from CCP5
bit 6-4
Unimplemented: Read as ‘0’
bit 3-2
PVCFG<1:0>: Positive Voltage Reference Configuration bits
00 = A/D VREF+ connected to internal signal, AVDD
01 = A/D VREF+ connected to external pin, VREF+
10 = A/D VREF+ connected to internal signal, FVR BUF2
11 = Reserved (by default, A/D VREF+ connected to internal signal, AVDD)
bit 1-0
NVCFG0<1:0>: Negative Voltage Reference Configuration bits
00 = A/D VREF- connected to internal signal, AVSS
01 = A/D VREF- connected to external pin, VREF10 = Reserved (by default, A/D VREF+ connected to internal signal, AVSS)
11 = Reserved (by default, A/D VREF+ connected to internal signal, AVSS)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 299
PIC18(L)F2X/4XK22
REGISTER 17-3:
ADCON2: A/D CONTROL REGISTER 2
R/W-0
U-0
ADFM
—
R/W-0
R/W-0
R/W-0
R/W-0
ACQT<2:0>
R/W-0
R/W-0
ADCS<2:0>
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
x = Bit is unknown
ADFM: A/D Conversion 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. Acquisition time is the duration that the A/D charge holding capacitor remains connected to A/D channel from the instant the GO/DONE bit is set until conversions begins.
000 = 0(1)
001 = 2 TAD
010 = 4 TAD
011 = 6 TAD
100 = 8 TAD
101 = 12 TAD
110 = 16 TAD
111 = 20 TAD
bit 2-0
ADCS<2:0>: A/D Conversion Clock Select bits
000 = FOSC/2
001 = FOSC/8
010 = FOSC/32
011 = FRC(1) (clock derived from a dedicated internal oscillator = 600 kHz nominal)
100 = FOSC/4
101 = FOSC/16
110 = FOSC/64
111 = FRC(1) (clock derived from a dedicated internal oscillator = 600 kHz nominal)
Note 1:
When the A/D clock source is selected as FRC then the start of conversion is delayed by one instruction
cycle after the GO/DONE bit is set to allow the SLEEP instruction to be executed.
DS41412C-page 300
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 17-4:
R/W-x
ADRESH: ADC RESULT REGISTER HIGH (ADRESH) ADFM = 0
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
ADRES<9:2>
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
bit 7-0
x = Bit is unknown
ADRES<9:2>: ADC Result Register bits
Upper 8 bits of 10-bit conversion result
REGISTER 17-5:
R/W-x
ADRESL: ADC RESULT REGISTER LOW (ADRESL) ADFM = 0
R/W-x
ADRES<1:0>
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
—
—
—
—
—
—
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 7-6
ADRES<1:0>: ADC Result Register bits
Lower 2 bits of 10-bit conversion result
bit 5-0
Reserved: Do not use.
REGISTER 17-6:
x = Bit is unknown
ADRESH: ADC RESULT REGISTER HIGH (ADRESH) ADFM = 1
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
—
—
—
—
—
—
R/W-x
R/W-x
ADRES<9:2>
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
bit 7-2
Reserved: Do not use.
bit 1-0
ADRES<9:8>: ADC Result Register bits
Upper 2 bits of 10-bit conversion result
REGISTER 17-7:
R/W-x
x = Bit is unknown
ADRESL: ADC RESULT REGISTER LOW (ADRESL) ADFM = 1
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
ADRES<7:0>
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 7-0
x = Bit is unknown
ADRES<7:0>: ADC Result Register bits
Lower 8 bits of 10-bit conversion result
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 301
PIC18(L)F2X/4XK22
17.3
A/D Acquisition Requirements
For the ADC 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 17-5. 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), see Figure 17-5.
The maximum recommended impedance for analog
sources is 10 k. As the source impedance is
decreased, the acquisition time may be decreased.
After the analog input channel is selected (or changed),
EQUATION 17-1:
an A/D acquisition must be done before the conversion
can be started. To calculate the minimum acquisition
time, Equation 17-1 may be used. This equation
assumes that 1/2 LSb error is used (1024 steps for the
ADC). The 1/2 LSb error is the maximum error allowed
for the ADC to meet its specified resolution.
ACQUISITION TIME EXAMPLE
Temperature = 50°C and external impedance of 10k  3.0V V DD
Assumptions:
T ACQ = Amplifier Settling Time + Hold Capacitor Charging Time + Temperature Coefficient
= T AMP + T C + T COFF
= 5µs + T C +   Temperature - 25°C   0.05µs/°C  
The value for TC can be approximated with the following equations:
1
V AP PLIE D  1 – ------------ = V CHOLD

2047
;[1] VCHOLD charged to within 1/2 lsb
–TC
----------

RC
V AP P LI ED  1 – e  = V CHOLD


;[2] VCHOLD charge response to VAPPLIED
– Tc
---------

1
RC
V AP P LIED  1 – e  = V A P PLIE D  1 – ------------

2047


;combining [1] and [2]
Solving for TC:
T C = – C HOLD  R IC + R SS + R S  ln(1/2047)
= – 13.5pF  1k  + 700  + 10k   ln(0.0004885)
= 1.20 µs
Therefore:
T ACQ = 5µs + 1.20µs +   50°C- 25°C   0.05  s/ °C  
= 7.45µs
Note 1: The reference voltage (VREF) has no effect on the equation, since it cancels itself out.
2: The charge holding capacitor (CHOLD) is discharged after each conversion.
3: The maximum recommended impedance for analog sources is 10 k. This is required to meet the pin
leakage specification.
DS41412C-page 302
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 17-5:
ANALOG INPUT MODEL
VDD
Rs
VA
ANx
RIC  1k
CPIN
5 pF
I LEAKAGE(1)
Sampling
Switch
SS Rss
CHOLD = 13.5 pF
Discharge
Switch
Note 1:
VDD
Legend: CPIN
= Input Capacitance
I LEAKAGE = Leakage current at the pin due to
various junctions
= Interconnect Resistance
RIC
SS
= Sampling Switch
CHOLD
= Sample/Hold Capacitance
VSS/VREF-
3.5V
3.0V
2.5V
2.0V
1.5V
.1
1
10
Rss (k)
100
See Section 27.0 “Electrical Characteristics”.
FIGURE 17-6:
ADC TRANSFER FUNCTION
Full-Scale Range
3FFh
3FEh
ADC Output Code
3FDh
3FCh
1/2 LSB ideal
3FBh
Full-Scale
Transition
004h
003h
002h
001h
000h
Analog Input Voltage
1/2 LSB ideal
VSS/VREF-
 2010 Microchip Technology Inc.
Zero-Scale
Transition
VDD/VREF+
Preliminary
DS41412C-page 303
PIC18(L)F2X/4XK22
TABLE 17-2:
Name
REGISTERS ASSOCIATED WITH A/D OPERATION
Bit 7
Bit 6
Bit 5
—
ADCON0
—
ADCON1
TRIGSEL
—
ADCON2
ADFM
—
Bit 4
Bit 3
Bit 2
CHS<4:0>
—
Bit 0
GO/DONE
ADON
PVCFG<1:0>
NVCFG<1:0>
ACQT<2:0>
ADRESH
Bit 1
ADCS<2:0>
298
299
300
A/D Result, High Byte
ADRESL
Register
on Page
301
A/D Result, Low Byte
301
ANSELA
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
152
ANSELB
—
—
ANSB5
ANSB4
ANSB3
ANSB2
ANSB1
ANSB0
153
ANSELC
ANSC7
ANSC6
ANSC5
ANSC4
ANSC3
ANSC2
—
—
153
ANSELD(1)
ANSD7
ANSD6
ANSD5
ANSD4
ANSD3
ANSD2
ANSD1
ANSD0
153
ANSELE(1)
—
—
—
—
—
ANSE2
ANSE1
ANSE0
154
EDGEN
EDGSEQEN
CTTRIG
329
—
—
CTMUCONH
CTMUEN
—
CTMUSIDL
TGEN
INTCON
CCP5CON
DC5B<1:0>
CCP5M<3:0>
IDISSEN
201
GIE/GIEH
PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR1
—
ADIP
RC1IP
TX1IP
SSP1IP
CCP1IP
TMR2IP
TMR1IP
127
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
129
IPR4
—
—
—
—
—
CCP5IP
CCP4IP
CCP3IP
130
PIE1
—
ADIE
RC1IE
TX1IE
SSP1IE
CCP1IE
TMR2IE
TMR1IE
123
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIE4
—
—
—
—
—
CCP5IE
CCP4IE
CCP3IE
126
PIR1
—
ADIF
RC1IF
TX1IF
SSP1IF
CCP1IF
TMR2IF
TMR1IF
118
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
PIR4
—
—
—
—
—
CCP5IF
CCP4IF
CCP3IF
121
PMD1
MSSP2MD
MSSP1MD
—
CCP5MD
CCP4MD
CCP3MD
CCP2MD
CCP1MD
57
PMD2
—
—
—
—
CTMUMD
CMP2MD
CMP1MD
ADCMD
58
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
154
TRISD(1)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
154
TRISE
WPUE3
—
—
—
—
TRISE2(1)
TRISE1(1)
TRISE0(1)
154
Legend:
Note 1:
— = unimplemented locations, read as ‘0’. Shaded bits are not used by this module.
Available on PIC18(L)F4XK22 devices.
TABLE 17-3:
Name
CONFIG3H
Legend:
CONFIGURATION REGISTERS ASSOCIATED WITH THE ADC MODULE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
MCLRE
—
P2BMX
T3CMX
HFOFST
Bit 2
CCP3MX
Bit 1
Bit 0
Register
on Page
PBADEN
CCP2MX
354
— = unimplemented locations, read as ‘0’. Shaded bits are not used by the ADC module.
DS41412C-page 304
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
18.0
COMPARATOR MODULE
FIGURE 18-1:
Comparators are used to interface analog circuits to a
digital circuit by comparing two analog voltages and
providing a digital indication of their relative magnitudes.
The comparators are very useful mixed signal building
blocks because they provide analog functionality
independent of the program execution. The analog
comparator module includes the following features:
•
•
•
•
•
•
•
•
•
•
Independent comparator control
Programmable input selection
Comparator output is available internally/externally
Programmable output polarity
Interrupt-on-change
Wake-up from Sleep
Programmable Speed/Power optimization
PWM shutdown
Programmable and fixed voltage reference
Selectable Hysteresis
18.1
SINGLE COMPARATOR
VIN+
+
VIN-
–
Output
VINVIN+
Output
Note:
The black areas of the output of the
comparator represents the uncertainty
due to input offsets and response time.
Comparator Overview
A single comparator is shown in Figure 18-1 along with
the relationship between the analog input levels and
the digital output. When the analog voltage at VIN+ is
less than the analog voltage at VIN-, the output of the
comparator is a digital low level. When the analog
voltage at VIN+ is greater than the analog voltage at
VIN-, the output of the comparator is a digital high level.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 305
PIC18(L)F2X/4XK22
FIGURE 18-2:
COMPARATOR C1/C2 SIMPLIFIED BLOCK DIAGRAM
CxCH<1:0>
CxON(1)
2
C12IN0-
0
C12IN1-
1
C12IN2-
CxSP
D
CxVIN-
2
C12IN3-
CxVIN+
3
Q1
-
(2),(3)
EN
Cx
+
D
Q3(2)
0
DAC
1
0
FVR BUF1 1
Read or Write
of CMxCON0
CxPOL
Q
To Interrupts
(CxIF)
EN
CL
CxR
CxIN+
Q
To CMxCON0 (CxOUT)
CM2CON1 (MCxOUT)
Reset
CxSYNC
CXVREF
Cx Output
to PWM Logic
CxOE
TRIS bit
0
CXRSEL
D
Q
1
CxOUT
Timer1 Clock
SYNCCxOUT
- to SR Latch
- to TxG MUX(4)
Note 1:
2:
3:
4:
When C1ON = 0, the C1 comparator will produce a ‘0’ output to the XOR Gate.
Q1 and Q3 are phases of the four-phase system clock (FOSC).
Q1 is held high during Sleep mode.
Synchronized comparator output should not be used to gate Timer1 in conjunction with synchronized T1CKI.
DS41412C-page 306
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
18.2
Comparator Control
Each comparator has a separate control and
Configuration register: CM1CON0 for Comparator C1
and CM2CON0 for Comparator C2. In addition,
Comparator C2 has a second control register,
CM2CON1, for controlling the interaction with Timer1 and
simultaneous reading of both comparator outputs.
The CM1CON0 and CM2CON0 registers (see Registers
18-1 and 18-2, respectively) contain the control and
status bits for the following:
•
•
•
•
•
•
2: The internal output of the comparator is
latched with each instruction cycle.
Unless otherwise specified, external
outputs are not latched.
18.2.5
COMPARATOR OUTPUT POLARITY
Inverting the output of the comparator is functionally
equivalent to swapping the comparator inputs. The
polarity of the comparator output can be inverted by
setting the CxPOL bit of the CMxCON0 register.
Clearing the CxPOL bit results in a non-inverted output.
Enable
Input selection
Reference selection
Output selection
Output polarity
Speed selection
18.2.1
Note 1: The CxOE bit overrides the PORT data
latch. Setting the CxON has no impact on
the port override.
Table 18-1 shows the output state versus input
conditions, including polarity control.
TABLE 18-1:
COMPARATOR ENABLE
COMPARATOR OUTPUT
STATE VS. INPUT
CONDITIONS
Setting the CxON bit of the CMxCON0 register enables
the comparator for operation. Clearing the CxON bit
disables the comparator resulting in minimum current
consumption.
Input Condition
CxPOL
CxOUT
CxVIN- > CxVIN+
0
0
18.2.2
CxVIN- < CxVIN+
0
1
CxVIN- > CxVIN+
1
1
CxVIN- < CxVIN+
1
0
COMPARATOR INPUT SELECTION
The CxCH<1:0> bits of the CMxCON0 register direct
one of four analog input pins to the comparator
inverting input.
Note:
18.2.3
To use CxIN+ and C12INx- pins as analog
inputs, the appropriate bits must be set in
the ANSEL register and the corresponding
TRIS bits must also be set to disable the
output drivers.
COMPARATOR REFERENCE
SELECTION
Setting the CxR bit of the CMxCON0 register directs an
internal voltage reference or an analog input pin to the
non-inverting input of the comparator. See
Section 21.0 “Fixed Voltage Reference (FVR)” for
more information on the Internal Voltage Reference
module.
18.2.4
COMPARATOR OUTPUT
SELECTION
The output of the comparator can be monitored by
reading either the CxOUT bit of the CMxCON0 register
or the MCxOUT bit of the CM2CON1 register. In order
to make the output available for an external connection,
the following conditions must be true:
18.2.6
COMPARATOR SPEED SELECTION
The trade-off between speed or power can be
optimized during program execution with the CxSP
control bit. The default state for this bit is ‘1’ which
selects the normal speed mode. Device power
consumption can be optimized at the cost of slower
comparator propagation delay by clearing the CxSP bit
to ‘0’.
18.3
Comparator Response Time
The comparator output is indeterminate for a period of
time after the change of an input source or the selection
of a new reference voltage. This period is referred to as
the response time. The response time of the
comparator differs from the settling time of the voltage
reference. Therefore, both of these times must be
considered when determining the total response time
to a comparator input change. See the Comparator and
Voltage Reference Specifications in Section 27.0
“Electrical Characteristics” for more details.
• CxOE bit of the CMxCON0 register must be set
• Corresponding TRIS bit must be cleared
• CxON bit of the CMxCON0 register must be set
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 307
PIC18(L)F2X/4XK22
18.4
Comparator Interrupt Operation
18.4.1
The comparator interrupt flag will be set whenever
there is a change in the output value of the comparator.
Changes are recognized by means of a mismatch
circuit which consists of two latches and an exclusiveor gate (see Figure 18-2). The first latch is updated with
the comparator output value, when the CMxCON0
register is read or written. The value is latched on the
third cycle of the system clock, also known as Q3. This
first latch retains the comparator value until another
read or write of the CMxCON0 register occurs or a
Reset takes place. The second latch is updated with
the comparator output value on every first cycle of the
system clock, also known as Q1. When the output
value of the comparator changes, the second latch is
updated and the output values of both latches no
longer match one another, resulting in a mismatch
condition. The latch outputs are fed directly into the
inputs of an exclusive-or gate. This mismatch condition
is detected by the exclusive-or gate and sent to the
interrupt circuitry. The mismatch condition will persist
until the first latch value is updated by performing a
read of the CMxCON0 register or the comparator
output returns to the previous state.
Note 1: A write operation to the CMxCON0
register will also clear the mismatch
condition because all writes include a read
operation at the beginning of the write
cycle.
2: Comparator interrupts will operate correctly
regardless of the state of CxOE.
When the mismatch condition occurs, the comparator
interrupt flag is set. The interrupt flag is triggered by the
edge of the changing value coming from the exclusiveor gate. This means that the interrupt flag can be reset
once it is triggered without the additional step of reading or writing the CMxCON0 register to clear the mismatch latches. When the mismatch registers are
cleared, an interrupt will occur upon the comparator’s
return to the previous state, otherwise no interrupt will
be generated.
Software will need to maintain information about the
status of the comparator output, as read from the
CMxCON0 register, or CM2CON1 register, to determine
the actual change that has occurred. See Figures 18-3
and 18-4.
The comparator mismatch latches can be preset to the
desired state before the comparators are enabled.
When the comparator is off the CxPOL bit controls the
CxOUT level. Set the CxPOL bit to the desired CxOUT
non-interrupt level while the CxON bit is cleared. Then,
configure the desired CxPOL level in the same instruction that the CxON bit is set. Since all register writes are
performed as a read-modify-write, the mismatch
latches will be cleared during the instruction read
phase and the actual configuration of the CxON and
CxPOL bits will be occur in the final write phase.
FIGURE 18-3:
COMPARATOR
INTERRUPT TIMING W/O
CMxCON0 READ
Q1
Q3
CxIN+
TRT
CxIN
Set CxIF (edge)
CxIF
Reset by Software
FIGURE 18-4:
COMPARATOR
INTERRUPT TIMING WITH
CMxCON0 READ
Q1
Q3
CxIN+
TRT
CxOUT
Set CxIF (edge)
CxIF
Cleared by CMxCON0 Read
Reset by Software
Note 1: If a change in the CMxCON0 register
(CxOUT) should occur when a read operation is being executed (start of the Q2
cycle), then the CxIF interrupt flag of the
PIR2 register may not get set.
The CxIF bit of the PIR2 register is the comparator
interrupt flag. This bit must be reset by software by
clearing it to ‘0’. Since it is also possible to write a ‘1’ to
this register, an interrupt can be generated.
In mid-range Compatibility mode the CxIE bit of the
PIE2 register and the PEIE/GIEL and GIE/GIEH bits of
the INTCON register must all be set to enable comparator interrupts. If any of these bits are cleared, the interrupt is not enabled, although the CxIF bit of the PIR2
register will still be set if an interrupt condition occurs.
DS41412C-page 308
PRESETTING THE MISMATCH
LATCHES
Preliminary
2: When either comparator is first enabled,
bias circuitry in the comparator module
may cause an invalid output from the
comparator until the bias circuitry is stable.
Allow about 1 s for bias settling then clear
the mismatch condition and interrupt flags
before enabling comparator interrupts.
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
18.5
Operation During Sleep
18.6
The comparator, if enabled before entering Sleep mode,
remains active during Sleep. The additional current
consumed by the comparator is shown separately in
Section 27.0 “Electrical Characteristics”. If the
comparator is not used to wake the device, power
consumption can be minimized while in Sleep mode by
turning off the comparator. Each comparator is turned off
by clearing the CxON bit of the CMxCON0 register.
Effects of a Reset
A device Reset forces the CMxCON0 and CM2CON1
registers to their Reset states. This forces both
comparators and the voltage references to their Off
states.
A change to the comparator output can wake-up the
device from Sleep. To enable the comparator to wake
the device from Sleep, the CxIE bit of the PIE2 register
and the PEIE/GIEL bit of the INTCON register must be
set. The instruction following the SLEEP instruction
always executes following a wake from Sleep. If the
GIE/GIEH bit of the INTCON register is also set, the
device will then execute the Interrupt Service Routine.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 309
PIC18(L)F2X/4XK22
REGISTER 18-1:
CM1CON0: COMPARATOR 1 CONTROL REGISTER
R/W-0
R-0
R/W-0
R/W-0
R/W-1
R/W-0
C1ON
C1OUT
C1OE
C1POL
C1SP
C1R
R/W-0
R/W-0
C1CH<1:0>
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
C1ON: Comparator C1 Enable bit
1 = Comparator C1 is enabled
0 = Comparator C1 is disabled
bit 6
C1OUT: Comparator C1 Output bit
If C1POL = 1 (inverted polarity):
C1OUT = 0 when C1VIN+ > C1VINC1OUT = 1 when C1VIN+ < C1VINIf C1POL = 0 (non-inverted polarity):
C1OUT = 1 when C1VIN+ > C1VINC1OUT = 0 when C1VIN+ < C1VIN-
bit 5
C1OE: Comparator C1 Output Enable bit
1 = C1OUT is present on the C1OUT pin(1)
0 = C1OUT is internal only
bit 4
C1POL: Comparator C1 Output Polarity Select bit
1 = C1OUT logic is inverted
0 = C1OUT logic is not inverted
bit 3
C1SP: Comparator C1 Speed/Power Select bit
1 = C1 operates in normal power, higher speed mode
0 = C1 operates in low-power, low-speed mode
bit 2
C1R: Comparator C1 Reference Select bit (non-inverting input)
1 = C1VIN+ connects to C1VREF output
0 = C1VIN+ connects to C12IN+ pin
bit 1-0
C1CH<1:0>: Comparator C1 Channel Select bit
00 = C12IN0- pin of C1 connects to C1VIN01 = C12IN1- pin of C1 connects to C1VIN10 = C12IN2- pin of C1 connects to C1VIN11 = C12IN3- pin of C1 connects to C1VIN-
Note 1:
x = Bit is unknown
Comparator output requires the following three conditions: C1OE = 1, C1ON = 1 and corresponding port
TRIS bit = 0.
DS41412C-page 310
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 18-2:
CM2CON: COMPARATOR 2 CONTROL REGISTER
R/W-0
R-0
R/W-0
R/W-0
R/W-1
R/W-0
C2ON
C2OUT
C2OE
C2POL
C2SP
C2R
R/W-0
R/W-0
C2CH<1:0>
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
C2ON: Comparator C2 Enable bit
1 = Comparator C2 is enabled
0 = Comparator C2 is disabled
bit 6
C2OUT: Comparator C2 Output bit
If C2POL = 1 (inverted polarity):
C2OUT = 0 when C2VIN+ > C2VINC2OUT = 1 when C2VIN+ < C2VINIf C2POL = 0 (non-inverted polarity):
C2OUT = 1 when C2VIN+ > C2VINC2OUT = 0 when C2VIN+ < C2VIN-
bit 5
C2OE: Comparator C2 Output Enable bit
1 = C2OUT is present on C2OUT pin(1)
0 = C2OUT is internal only
bit 4
C2POL: Comparator C2 Output Polarity Select bit
1 = C2OUT logic is inverted
0 = C2OUT logic is not inverted
bit 3
C2SP: Comparator C2 Speed/Power Select bit
1 = C2 operates in normal power, higher speed mode
0 = C2 operates in low-power, low-speed mode
bit 2
C2R: Comparator C2 Reference Select bits (non-inverting input)
1 = C2VIN+ connects to C2VREF
0 = C2VIN+ connects to C2IN+ pin
bit 1-0
C2CH<1:0>: Comparator C2 Channel Select bits
00 = C12IN0- pin of C2 connects to C2VIN01 = C12IN1- pin of C2 connects to C2VIN10 = C12IN2- pin of C2 connects to C2VIN11 = C12IN3- pin of C2 connects to C2VIN-
Note 1:
x = Bit is unknown
Comparator output requires the following three conditions: C2OE = 1, C2ON = 1 and corresponding port
TRIS bit = 0.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 311
PIC18(L)F2X/4XK22
18.7
Analog Input Connection
Considerations
A simplified circuit for an analog input is shown in
Figure 18-5. Since the analog input pins share their
connection with a digital input, they have reverse
biased ESD protection diodes to VDD and VSS. The
analog input, therefore, must be between VSS and VDD.
If the input voltage deviates from this range by more
than 0.6V in either direction, one of the diodes is
forward biased and a latch-up may occur.
Note 1: When reading a PORT register, all pins
configured as analog inputs will read as a
‘0’. Pins configured as digital inputs will
convert as an analog input, according to
the 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.
A maximum source impedance of 10 k is recommended
for the analog sources. Also, any external component
connected to an analog input pin, such as a capacitor or
a Zener diode, should have very little leakage current to
minimize inaccuracies introduced.
FIGURE 18-5:
ANALOG INPUT MODEL
VDD
VT  0.6V
Rs < 10K
RIC
To Comparator
AIN
VA
CPIN
5 pF
VT  0.6V
ILEAKAGE(1)
Vss
Legend: CPIN
= Input Capacitance
ILEAKAGE = Leakage Current at the pin due to various junctions
RIC
= Interconnect Resistance
= Source Impedance
RS
= Analog Voltage
VA
VT
= Threshold Voltage
Note 1: See Section 27.0 “Electrical Characteristics”.
DS41412C-page 312
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
18.8
Additional Comparator Features
Simultaneous read of comparator outputs
Internal reference selection
Hysteresis selection
Output Synchronization
18.8.1
18.8.4
SIMULTANEOUS COMPARATOR
OUTPUT READ
The MC1OUT and MC2OUT bits of the CM2CON1
register are mirror copies of both comparator outputs.
The ability to read both outputs simultaneously from a
single register eliminates the timing skew of reading
separate registers.
Note 1: Obtaining the status of C1OUT or C2OUT
by reading CM2CON1 does not affect the
comparator interrupt mismatch registers.
18.8.2
INTERNAL REFERENCE
SELECTION
There are two internal voltage references available to
the non-inverting input of each comparator. One of
these is the Fixed Voltage Reference (FVR) and the
other is the variable Digital-to-Analog Converter (DAC).
The CxRSEL bit of the CM2CON1 register determines
which of these references is routed to the Comparator
Voltage reference output (CXVREF). Further routing to
the comparator is accomplished by the CxR bit of the
CMxCON0 register. See Section 21.0 “Fixed Voltage
Reference (FVR)” and Figure 18-2 for more detail.
 2010 Microchip Technology Inc.
COMPARATOR HYSTERESIS
Each Comparator has a selectable hysteresis feature.
The hysteresis can be enabled by setting the CxHYS
bit of the CM2CON1 register. See Section 27.0 “Electrical Characteristics” for more details.
There are four additional comparator features:
•
•
•
•
18.8.3
SYNCHRONIZING COMPARATOR
OUTPUT TO TIMER1
The Comparator Cx output can be synchronized with
Timer1 by setting the CxSYNC bit of the CM2CON1
register. When enabled, the Cx output is latched on
the falling edge of the Timer1 source clock. To prevent
a race condition when gating Timer1 clock with the
comparator output, Timer1 increments on the rising
edge of its clock source, and the falling edge latches
the comparator output. See the Comparator Block
Diagram (Figure 18-2) and the Timer1 Block Diagram
(Figure 12-1) for more information.
Note 1: The comparator synchronized output
should not be used to gate the external
Timer1 clock when the Timer1
synchronizer is enabled.
Preliminary
2: The Timer1 prescale should be set to 1:1
when synchronizing the comparator
output as unexpected results may occur
with other prescale values.
DS41412C-page 313
PIC18(L)F2X/4XK22
REGISTER 18-3:
CM2CON1: COMPARATOR 1 AND 2 CONTROL REGISTER
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
MC1OUT
MC2OUT
C1RSEL
C2RSEL
C1HYS
C2HYS
C1SYNC
C2SYNC
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
MC1OUT: Mirror Copy of C1OUT bit
bit 6
MC2OUT: Mirror Copy of C2OUT bit
bit 5
C1RSEL: Comparator C1 Reference Select bit
1 = FVR BUF1 routed to C1VREF input
0 = DAC routed to C1VREF input
bit 4
C2RSEL: Comparator C2 Reference Select bit
1 = FVR BUF1 routed to C2VREF input
0 = DAC routed to C2VREF input
bit 3
C1HYS: Comparator C1 Hysteresis Enable bit
1 = Comparator C1 hysteresis enabled
0 = Comparator C1 hysteresis disabled
bit 2
C2HYS: Comparator C2 Hysteresis Enable bit
1 = Comparator C2 hysteresis enabled
0 = Comparator C2 hysteresis disabled
bit 1
C1SYNC: C1 Output Synchronous Mode bit
1 = C1 output is synchronized to rising edge of TMR1 clock (T1CLK)
0 = C1 output is asynchronous
bit 0
C2SYNC: C2 Output Synchronous Mode bit
1 = C2 output is synchronized to rising edge of TMR1 clock (T1CLK)
0 = C2 output is asynchronous
DS41412C-page 314
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 18-2:
Name
ANSELA
ANSELB
REGISTERS ASSOCIATED WITH COMPARATOR MODULE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
—
—
ANSA5
—
ANSA3
ANSA2
ANSA1
ANSA0
152
ANSB5
ANSB4
—
—
CM2CON1
MC1OUT
MC2OUT
CM1CON0
C1ON
C1OUT
C1OE
CM2CON0
C2ON
C2OUT
C2OE
—
VREFCON1
DACEN
DACLPS
DACOE
VREFCON2
—
—
—
VREFCON0
INTCON
FVREN
GIE/GIEH
FVRST
ANSB3
ANSB2
ANSB1
ANSB0
153
C1HYS
C2HYS
C1SYNC
C2SYNC
314
C1POL
C1SP
C1R
C1CH<1:0>
C2POL
C2SP
C2R
C2CH<1:0>
C1RSEL C2RSEL
—
DACNSS
DACR<4:0>
FVRS<1:0>
PEIE/GIEL TMR0IE
DACPSS<1:0>
310
311
341
342
—
—
—
—
338
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
PMD2
—
—
—
—
ADCMD
58
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
CTMUMD CMP2MD CMP1MD
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are not used by the Comparator Module.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 315
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 316
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
19.0
CHARGE TIME
MEASUREMENT UNIT (CTMU)
• Time measurement resolution of 1 nanosecond
• High precision time measurement
• Time delay of external or internal signal
asynchronous to system clock
• Accurate current source suitable for capacitive
measurement
The Charge Time Measurement Unit (CTMU) is a
flexible analog module that provides accurate
differential time measurement between pulse sources,
as well as asynchronous pulse generation. By working
with other on-chip analog modules, the CTMU can be
used to precisely measure time, measure capacitance,
measure relative changes in capacitance or generate
output pulses with a specific time delay. The CTMU is
ideal for interfacing with capacitive-based sensors.
The CTMU works in conjunction with the A/D Converter
to provide up to 28(1) channels for time or charge
measurement, depending on the specific device and
the number of A/D channels available. When configured for time delay, the CTMU is connected to the
C12IN1- input of Comparator 2. The level-sensitive
input edge sources can be selected from four sources:
two external input pins (CTED1/CTED2) or the ECCP1/
(E)CCP2 Special Event Triggers.
The module includes the following key features:
• Up to 28(1) channels available for capacitive or
time measurement input
• On-chip precision current source
• Four-edge input trigger sources
• Polarity control for each edge source
• Control of edge sequence
• Control of response to edges
FIGURE 19-1:
Figure 19-1 provides a block diagram of the CTMU.
Note 1: PIC18(L)F2XK22 devices have up to 17
channels available.
CTMU BLOCK DIAGRAM
CTMUCONH/CTMUCONL
EDGEN
EDGSEQEN
EDG1SELx
EDG1POL
EDG2SELx
EDG2POL
CTED1
CTED2
CTMUICON
ITRIM<5:0>
IRNG<1:0>
EDG1STAT
EDG2STAT
Edge
Control
Logic
Current Source
Current
Control
ECCP2
TGEN
IDISSEN
CTTRIG
CTMU
Control
Logic
Pulse
Generator
ECCP1
A/D Converter
CTPLS
Comparator 2
Input
Comparator 2 Output
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 317
PIC18(L)F2X/4XK22
19.1
CTMU Operation
19.1.2
The CTMU works by using a fixed current source to
charge a circuit. The type of circuit depends on the type
of measurement being made. In the case of charge
measurement, the current is fixed, and the amount of
time the current is applied to the circuit is fixed. The
amount of voltage read by the A/D is then a measurement of the capacitance of the circuit. In the case of
time measurement, the current, as well as the capacitance of the circuit, is fixed. In this case, the voltage
read by the A/D is then representative of the amount of
time elapsed from the time the current source starts
and stops charging the circuit.
CURRENT SOURCE
At the heart of the CTMU is a precision current source,
designed to provide a constant reference for measurements. The level of current is user-selectable across
three ranges or a total of two orders of magnitude, with
the ability to trim the output in ±2% increments
(nominal). The current range is selected by the
IRNG<1:0> bits (CTMUICON<1:0>), with a value of
‘00’ representing the lowest range.
If the CTMU is being used as a time delay, both
capacitance and current source are fixed, as well as the
voltage supplied to the comparator circuit. The delay of
a signal is determined by the amount of time it takes the
voltage to charge to the comparator threshold voltage.
Current trim is provided by the ITRIM<5:0> bits
(CTMUICON<7:2>). These six bits allow trimming of
the current source in steps of approximately 2% per
step. Note that half of the range adjusts the current
source positively and the other half reduces the current
source. A value of ‘000000’ is the neutral position (no
change). A value of ‘100000’ is the maximum negative
adjustment (approximately -62%) and ‘011111’ is the
maximum positive adjustment (approximately +62%).
19.1.1
19.1.3
THEORY OF OPERATION
The operation of the CTMU is based on the equation
for charge:
dV
C = I  ------dT
More simply, the amount of charge measured in
coulombs in a circuit is defined as current in amperes
(I) multiplied by the amount of time in seconds that the
current flows (t). Charge is also defined as the
capacitance in farads (C) multiplied by the voltage of
the circuit (V). It follows that:
I  t = C  V.
The CTMU module provides a constant, known current
source. The A/D Converter is used to measure (V) in
the equation, leaving two unknowns: capacitance (C)
and time (t). The above equation can be used to calculate capacitance or time, by either the relationship
using the known fixed capacitance of the circuit:
t = C  V  I
or by:
C = I  t  V
using a fixed time that the current source is applied to
the circuit.
DS41412C-page 318
EDGE SELECTION AND CONTROL
CTMU measurements are controlled by edge events
occurring on the module’s two input channels. Each
channel, referred to as Edge 1 and Edge 2, can be configured to receive input pulses from one of the edge
input pins (CTED1 and CTED2) or ECCPx Special
Event Triggers. The input channels are level-sensitive,
responding to the instantaneous level on the channel
rather than a transition between levels. The inputs are
selected using the EDG1SEL and EDG2SEL bit pairs
(CTMUCONL<3:2 and 6:5>).
In addition to source, each channel can be configured for
event polarity using the EDGE2POL and EDGE1POL
bits (CTMUCONL<7,4>). The input channels can also
be filtered for an edge event sequence (Edge 1 occurring before Edge 2) by setting the EDGSEQEN bit
(CTMUCONH<2>).
19.1.4
EDGE STATUS
The CTMUCONL register also contains two Status bits:
EDG2STAT and EDG1STAT (CTMUCONL<1:0>).
Their primary function is to show if an edge response
has occurred on the corresponding channel. The
CTMU automatically sets a particular bit when an edge
response is detected on its channel. The level-sensitive
nature of the input channels also means that the Status
bits become set immediately if the channel’s configuration is changed and is the same as the channel’s
current state.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
The module uses the edge Status bits to control the
current source output to external analog modules (such
as the A/D Converter). Current is only supplied to
external modules when only one (but not both) of the
Status bits is set, and shuts current off when both bits
are either set or cleared. This allows the CTMU to
measure current only during the interval between
edges. After both Status bits are set, it is necessary to
clear them before another measurement is taken. Both
bits should be cleared simultaneously, if possible, to
avoid re-enabling the CTMU current source.
In addition to being set by the CTMU hardware, the
edge Status bits can also be set by software. This is
also the user’s application to manually enable or
disable the current source. Setting either one (but not
both) of the bits enables the current source. Setting or
clearing both bits at once disables the source.
19.1.5
INTERRUPTS
The CTMU sets its interrupt flag (PIR3<2>) whenever
the current source is enabled, then disabled. An
interrupt is generated only if the corresponding
interrupt enable bit (PIE3<2>) is also set. If edge
sequencing is not enabled (i.e., Edge 1 must occur
before Edge 2), it is necessary to monitor the edge
Status bits and determine which edge occurred last and
caused the interrupt.
19.2
CTMU Module Initialization
The following sequence is a general guideline used to
initialize the CTMU module:
1.
Select the current source range using the IRNG
bits (CTMUICON<1:0>).
2. Adjust the current source trim using the ITRIM
bits (CTMUICON<7:2>).
3. Configure the edge input sources for Edge 1 and
Edge 2 by setting the EDG1SEL and EDG2SEL
bits (CTMUCONL<3:2 and 6:5>).
4. Configure the input polarities for the edge inputs
using the EDG1POL and EDG2POL bits
(CTMUCONL<4,7>). The default configuration
is for negative edge polarity (high-to-low
transitions).
5. Enable edge sequencing using the EDGSEQEN
bit (CTMUCONH<2>). By default, edge
sequencing is disabled.
6. Select the operating mode (Measurement or
Time Delay) with the TGEN bit. The default
mode is Time/Capacitance Measurement.
7. Discharge the connected circuit by setting the
IDISSEN bit (CTMUCONH<1>); after waiting a
sufficient time for the circuit to discharge, clear
IDISSEN.
8. Disable the module by clearing the CTMUEN bit
(CTMUCONH<7>).
9. Enable the module by setting the CTMUEN bit.
10. Clear the Edge Status bits: EDG2STAT and
EDG1STAT (CTMUCONL<1:0>).
11. Enable both edge inputs by setting the EDGEN
bit (CTMUCONH<3>).
Depending on the type of measurement or pulse
generation being performed, one or more additional
modules may also need to be initialized and configured
with the CTMU module:
• Edge Source Generation: In addition to the
external edge input pins, both Timer1 and the
Output Compare/PWM1 module can be used as
edge sources for the CTMU.
• Capacitance or Time Measurement: The CTMU
module uses the A/D Converter to measure the
voltage across a capacitor that is connected to one
of the analog input channels.
• Pulse Generation: When generating system clock
independent output pulses, the CTMU module
uses Comparator 2 and the associated
comparator voltage reference.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 319
PIC18(L)F2X/4XK22
19.3
Calibrating the CTMU Module
FIGURE 19-2:
The CTMU requires calibration for precise
measurements of capacitance and time, as well as for
accurate time delay. If the application only requires
measurement of a relative change in capacitance or
time, calibration is usually not necessary. An example of
this type of application would include a capacitive touch
switch, in which the touch circuit has a baseline
capacitance, and the added capacitance of the human
body changes the overall capacitance of a circuit.
PIC18(L)FXXK22 Device
CTMU
Current Source
A/D Converter
If actual capacitance or time measurement is required,
two hardware calibrations must take place: the current
source needs calibration to set it to a precise current,
and the circuit being measured needs calibration to
measure and/or nullify all other capacitance other than
that to be measured.
19.3.1
4.
5.
6.
ANx
RCAL
A/D
MUX
CURRENT SOURCE CALIBRATION
The current source on board the CTMU module has a
range of ±60% nominal for each of three current
ranges. Therefore, for precise measurements, it is
possible to measure and adjust this current source by
placing a high precision resistor, RCAL, onto an unused
analog channel. An example circuit is shown in
Figure 19-2. The current source measurement is
performed using the following steps:
1.
2.
3.
CTMU CURRENT SOURCE
CALIBRATION CIRCUIT
Initialize the A/D Converter.
Initialize the CTMU.
Enable the current source by setting EDG1STAT
(CTMUCONL<0>).
Issue settling time delay.
Perform A/D conversion.
Calculate the current source current using
I = V/ RCAL, where RCAL is a high precision
resistance and V is measured by performing an
A/D conversion.
A value of 70% of full-scale voltage is chosen to make
sure that the A/D Converter was in a range that is well
above the noise floor. Keep in mind that if an exact current is chosen, that is to incorporate the trimming bits
from CTMUICON, the resistor value of RCAL may need
to be adjusted accordingly. RCAL may also be adjusted
to allow for available resistor values. RCAL should be of
the highest precision available, keeping in mind the
amount of precision needed for the circuit that the
CTMU will be used to measure. A recommended
minimum would be 0.1% tolerance.
The following examples show one typical method for
performing a CTMU current calibration. Example 19-1
demonstrates how to initialize the A/D Converter and
the CTMU; this routine is typical for applications using
both modules. Example 19-2 demonstrates one
method for the actual calibration routine.
The CTMU current source may be trimmed with the
trim bits in CTMUICON using an iterative process to get
an exact desired current. Alternatively, the nominal
value without adjustment may be used; it may be
stored by the software for use in all subsequent
capacitive or time measurements.
To calculate the value for RCAL, the nominal current
must be chosen, and then the resistance can be
calculated. For example, if the A/D Converter reference
voltage is 3.3V, use 70% of full scale, or 2.31V as the
desired approximate voltage to be read by the A/D
Converter. If the range of the CTMU current source is
selected to be 0.55 A, the resistor value needed is calculated as RCAL = 2.31V/0.55 A, for a value of 4.2 MΩ.
Similarly, if the current source is chosen to be 5.5 A,
RCAL would be 420,000Ω, and 42,000Ω if the current
source is set to 55 A.
DS41412C-page 320
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
EXAMPLE 19-1:
SETUP FOR CTMU CALIBRATION ROUTINES
#include "p18cxxx.h"
/**************************************************************************/
/*Setup CTMU *****************************************************************/
/**************************************************************************/
void setup(void)
{ //CTMUCONH/1 - CTMU Control registers
CTMUCONH = 0x00;
//make sure CTMU is disabled
CTMUCONL = 0x90;
//CTMU continues to run when emulator is stopped,CTMU continues
//to run in idle mode,Time Generation mode disabled, Edges are blocked
//No edge sequence order, Analog current source not grounded, trigger
//output disabled, Edge2 polarity = positive level, Edge2 source =
//source 0, Edge1 polarity = positive level, Edge1 source = source 0,
//CTMUICON - CTMU Current Control Register
CTMUICON = 0x01;
//0.55uA, Nominal - No Adjustment
/**************************************************************************/
//Setup AD converter;
/**************************************************************************/
TRISA=0x04;
//set channel 2 as an input
// Configure AN2 as an analog channel
ANSELAbits.ANSA2=1;
TRISAbits.TRISA2=1;
// ADCON2
ADCON2bits.ADFM=1;
ADCON2bits.ACQT=1;
ADCON2bits.ADCS=2;
// ADCON1
ADCON1bits.PVCFG0 =0;
ADCON1bits.NVCFG1 =0;
// ADCON0
ADCON0bits.CHS=2;
ADCON0bits.ADON=1;
// Results format 1= Right justified
// Acquition time 7 = 20TAD 2 = 4TAD 1=2TAD
// Clock conversion bits 6= FOSC/64 2=FOSC/32
// Vref+ = AVdd
// Vref- = AVss
// Select ADC channel
// Turn on ADC
}
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 321
PIC18(L)F2X/4XK22
EXAMPLE 19-2:
CURRENT CALIBRATION ROUTINE
#include "p18cxxx.h"
#define COUNT 500
#define DELAY for(i=0;i<COUNT;i++)
#define RCAL .027
#define ADSCALE 1023
#define ADREF 3.3
int main(void)
{
int i;
int j = 0;
unsigned int Vread = 0;
double VTot = 0;
float Vavg=0, Vcal=0, CTMUISrc = 0;
//@ 8MHz = 125uS.
//R value is 4200000 (4.2M)
//scaled so that result is in
//1/100th of uA
//for unsigned conversion 10 sig bits
//Vdd connected to A/D Vr+
//index for loop
//float values stored for calcs
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1;
CTMUCONLbits.EDG1STAT = 0;
CTMUCONLbits.EDG2STAT = 0;
for(j=0;j<10;j++)
{
CTMUCONHbits.IDISSEN = 1;
DELAY;
CTMUCONHbits.IDISSEN = 0;
CTMUCONLbits.EDG1STAT = 1;
//Enable the CTMU
// Set Edge status bits to zero
//drain charge on the circuit
//wait 125us
//end drain of circuit
DELAY;
CTMUCONLbits.EDG1STAT = 0;
//Begin charging the circuit
//using CTMU current source
//wait for 125us
//Stop charging circuit
PIR1bits.ADIF = 0;
ADCON0bits.GO=1;
while(!PIR1bits.ADIF);
//make sure A/D Int not set
//and begin A/D conv.
//Wait for A/D convert complete
Vread = ADRES;
PIR1bits.ADIF = 0;
VTot += Vread;
//Get the value from the A/D
//Clear A/D Interrupt Flag
//Add the reading to the total
}
Vavg = (float)(VTot/10.000);
Vcal = (float)(Vavg/ADSCALE*ADREF);
CTMUISrc = Vcal/RCAL;
//Average of 10 readings
//CTMUISrc is in 1/100ths of uA
}
DS41412C-page 322
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
19.3.2
CAPACITANCE CALIBRATION
There is a small amount of capacitance from the
internal A/D Converter sample capacitor as well as
stray capacitance from the circuit board traces and
pads that affect the precision of capacitance
measurements. A measurement of the stray
capacitance can be taken by making sure the desired
capacitance to be measured has been removed. The
measurement is then performed using the following
steps:
1.
2.
3.
4.
5.
6.
Initialize the A/D Converter and the CTMU.
Set EDG1STAT (= 1).
Wait for a fixed delay of time t.
Clear EDG1STAT.
Perform an A/D conversion.
Calculate the stray and A/D sample capacitances:
C OFFSET = C STRAY + C AD =  I  t   V
where I is known from the current source measurement
step, t is a fixed delay and V is measured by performing
an A/D conversion.
This measured value is then stored and used for
calculations of time measurement or subtracted for
capacitance measurement. For calibration, it is
expected that the capacitance of CSTRAY + CAD is
approximately known. CAD is approximately 4 pF.
An iterative process may need to be used to adjust the
time, t, that the circuit is charged to obtain a reasonable
voltage reading from the A/D Converter. The value of t
may be determined by setting COFFSET to a theoretical
value, then solving for t. For example, if CSTRAY is
theoretically calculated to be 11 pF, and V is expected
to be 70% of VDD, or 2.31V, then t would be:
(4 pF + 11 pF) • 2.31V/0.55 A
or 63 s.
See Example 19-3 for a typical routine for CTMU
capacitance calibration.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 323
PIC18(L)F2X/4XK22
EXAMPLE 19-3:
CAPACITANCE CALIBRATION ROUTINE
#include "p18cxxx.h"
#define
#define
#define
#define
bits
#define
#define
COUNT 25
ETIME COUNT*2.5
DELAY for(i=0;i<COUNT;i++)
ADSCALE 1023
//@ 8MHz INTFRC = 62.5 us.
//time in uS
ADREF 3.3
RCAL .027
//Vdd connected to A/D Vr+
//R value is 4200000 (4.2M)
//scaled so that result is in
//1/100th of uA
//for unsigned conversion 10 sig
int main(void)
{
int i;
int j = 0;
//index for loop
unsigned int Vread = 0;
float CTMUISrc, CTMUCap, Vavg, VTot, Vcal;
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1;
CTMUCONLbits.EDG1STAT = 0;
CTMUCONLbits.EDG2STAT = 0;
for(j=0;j<10;j++)
{
CTMUCONHbits.IDISSEN = 1;
DELAY;
CTMUCONHbits.IDISSEN = 0;
CTMUCONLbits.EDG1STAT = 1;
//Enable the CTMU
// Set Edge status bits to zero
//drain charge on the circuit
//wait 125us
//end drain of circuit
DELAY;
CTMUCONLbits.EDG1STAT = 0;
//Begin charging the circuit
//using CTMU current source
//wait for 125us
//Stop charging circuit
PIR1bits.ADIF = 0;
ADCON0bits.GO=1;
while(!PIR1bits.ADIF);
//make sure A/D Int not set
//and begin A/D conv.
//Wait for A/D convert complete
Vread = ADRES;
PIR1bits.ADIF = 0;
VTot += Vread;
//Get the value from the A/D
//Clear A/D Interrupt Flag
//Add the reading to the total
}
Vavg = (float)(VTot/10.000);
Vcal = (float)(Vavg/ADSCALE*ADREF);
CTMUISrc = Vcal/RCAL;
CTMUCap = (CTMUISrc*ETIME/Vcal)/100;
//Average of 10 readings
//CTMUISrc is in 1/100ths of uA
}
DS41412C-page 324
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
19.4
Measuring Capacitance with the
CTMU
There are two separate methods of measuring
capacitance with the CTMU. The first is the absolute
method, in which the actual capacitance value is
desired. The second is the relative method, in which
the actual capacitance is not needed, rather an
indication of a change in capacitance is required.
19.4.1
ABSOLUTE CAPACITANCE
MEASUREMENT
For absolute capacitance measurements, both the
current and capacitance calibration steps found in
Section 19.3 “Calibrating the CTMU Module”
should be followed. Capacitance measurements are
then performed using the following steps:
1.
2.
3.
4.
5.
6.
7.
8.
Initialize the A/D Converter.
Initialize the CTMU.
Set EDG1STAT.
Wait for a fixed delay, T.
Clear EDG1STAT.
Perform an A/D conversion.
Calculate the total capacitance, CTOTAL = (I * T)/V,
where I is known from the current source
measurement step (see Section 19.3.1 “Current
Source Calibration”), T is a fixed delay and V is
measured by performing an A/D conversion.
Subtract the stray and A/D capacitance
(COFFSET from Section 19.3.2 “Capacitance
Calibration”) from CTOTAL to determine the
measured capacitance.
 2010 Microchip Technology Inc.
19.4.2
RELATIVE CHARGE
MEASUREMENT
An application may not require precise capacitance
measurements. For example, when detecting a valid
press of a capacitance-based switch, detecting a relative change of capacitance is of interest. In this type of
application, when the switch is open (or not touched),
the total capacitance is the capacitance of the combination of the board traces, the A/D Converter, etc. A larger
voltage will be measured by the A/D Converter. When
the switch is closed (or is touched), the total
capacitance is larger due to the addition of the
capacitance of the human body to the above listed
capacitances, and a smaller voltage will be measured
by the A/D Converter.
Detecting capacitance changes is easily accomplished
with the CTMU using these steps:
1.
2.
3.
4.
5.
Initialize the A/D Converter and the CTMU.
Set EDG1STAT.
Wait for a fixed delay.
Clear EDG1STAT.
Perform an A/D conversion.
The voltage measured by performing the A/D
conversion is an indication of the relative capacitance.
Note that in this case, no calibration of the current
source or circuit capacitance measurement is needed.
See Example 19-4 for a sample software routine for a
capacitive touch switch.
Preliminary
DS41412C-page 325
PIC18(L)F2X/4XK22
EXAMPLE 19-4:
ROUTINE FOR CAPACITIVE TOUCH SWITCH
#include "p18cxxx.h"
#define
#define
#define
#define
COUNT 500
DELAY for(i=0;i<COUNT;i++)
OPENSW 1000
TRIP 300
#define HYST 65
//@ 8MHz = 125uS.
//Un-pressed switch value
//Difference between pressed
//and un-pressed switch
//amount to change
//from pressed to un-pressed
#define PRESSED 1
#define UNPRESSED 0
int main(void)
{
unsigned int Vread;
unsigned int switchState;
int i;
//storage for reading
//assume CTMU and A/D have been setup correctly
//see Example 25-1 for CTMU & A/D setup
setup();
CTMUCONHbits.CTMUEN = 1;
CTMUCONLbits.EDG1STAT = 0;
CTMUCONLbits.EDG2STAT = 0;
CTMUCONHbits.IDISSEN = 1;
DELAY;
CTMUCONHbits.IDISSEN = 0;
// Enable the CTMU
// Set Edge status bits to zero
CTMUCONLbits.EDG1STAT = 1;
DELAY;
CTMUCONLbits.EDG1STAT = 0;
//Begin charging the circuit
//using CTMU current source
//wait for 125us
//Stop charging circuit
PIR1bits.ADIF = 0;
ADCON0bits.GO=1;
while(!PIR1bits.ADIF);
//make sure A/D Int not set
//and begin A/D conv.
//Wait for A/D convert complete
Vread = ADRES;
//Get the value from the A/D
//drain charge on the circuit
//wait 125us
//end drain of circuit
if(Vread < OPENSW - TRIP)
{
switchState = PRESSED;
}
else if(Vread > OPENSW - TRIP + HYST)
{
switchState = UNPRESSED;
}
}
DS41412C-page 326
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
19.5
Measuring Time with the CTMU
Module
It is assumed that the time measured is small enough
that the capacitance, COFFSET, provides a valid voltage
to the A/D Converter. For the smallest time measurement, always set the A/D Channel Select register
(AD1CHS) to an unused A/D channel; the corresponding pin for which is not connected to any circuit board
trace. This minimizes added stray capacitance, keeping the total circuit capacitance close to that of the A/D
Converter itself (4-5 pF). To measure longer time
intervals, an external capacitor may be connected to an
A/D channel and this channel selected when making a
time measurement.
Time can be precisely measured after the ratio (C/I) is
measured from the current and capacitance calibration
step by following these steps:
1.
2.
3.
4.
5.
Initialize the A/D Converter and the CTMU.
Set EDG1STAT.
Set EDG2STAT.
Perform an A/D conversion.
Calculate the time between edges as T = (C/I) * V,
where I is calculated in the current calibration step
(Section 19.3.1 “Current Source Calibration”),
C is calculated in the capacitance calibration step
(Section 19.3.2 “Capacitance Calibration”) and
V is measured by performing the A/D conversion.
FIGURE 19-3:
TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR TIME
MEASUREMENT
PIC18(L)FXXK22 Device
CTMU
CTED1
EDG1
CTED2
EDG2
Current Source
Output Pulse
ANX
A/D Converter
CAD
RPR
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 327
PIC18(L)F2X/4XK22
19.6
Creating a Delay with the CTMU
Module
An example use of this feature is for interfacing with
variable capacitive-based sensors, such as a humidity
sensor. As the humidity varies, the pulse width output
on CTPLS will vary. The CTPLS output pin can be connected to an input capture pin and the varying pulse
width is measured to determine the humidity in the
application.
A unique feature on board the CTMU module is its
ability to generate system clock independent output
pulses based on an external capacitor value. This is
accomplished using the internal comparator voltage
reference module, Comparator 2 input pin and an
external capacitor. The pulse is output onto the CTPLS
pin. To enable this mode, set the TGEN bit.
Follow these steps to use this feature:
1.
2.
3.
See Figure 19-4 for an example circuit. CPULSE is
chosen by the user to determine the output pulse width
on CTPLS. The pulse width is calculated by
T = (CPULSE /I)*V, where I is known from the current
source measurement step (Section 19.3.1 “Current
Source Calibration”) and V is the internal reference
voltage (CVREF).
FIGURE 19-4:
4.
5.
Initialize Comparator 2.
Initialize the comparator voltage reference.
Initialize the CTMU and enable time delay
generation by setting the TGEN bit.
Set EDG1STAT.
When CPULSE charges to the value of the voltage
reference trip point, an output pulse is generated
on CTPLS.
TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR PULSE
DELAY GENERATION
PIC18(L)FXXK22 Device
CTED1
EDG1
CTMU
CTPLS
Current Source
Comparator
C12IN1-
CPULSE
19.7
19.7.1
C2
CVREF
Operation During Sleep/Idle
Modes
module is performing an operation when Idle mode is
invoked, in this case, the results will be similar to those
with Sleep mode.
SLEEP MODE AND DEEP SLEEP
MODES
19.8
When the device enters any Sleep mode, the CTMU
module current source is always disabled. If the CTMU
is performing an operation that depends on the current
source when Sleep mode is invoked, the operation may
not terminate correctly. Capacitance and time
measurements may return erroneous values.
19.7.2
CTMU Peripheral Module Disable
(PMD)
When this peripheral is not used, the Peripheral
Module Disable bit can be set to disconnect all clock
sources to the module, reducing power consumption to
an absolute minimum. See Section 3.6 “Selective
Peripheral Module Control”.
IDLE MODE
The behavior of the CTMU in Idle mode is determined
by the CTMUSIDL bit (CTMUCONH<5>). If CTMUSIDL
is cleared, the module will continue to operate in Idle
mode. If CTMUSIDL is set, the module’s current source
is disabled when the device enters Idle mode. If the
DS41412C-page 328
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
19.9
Effects of a Reset on CTMU
19.10 Registers
Upon Reset, all registers of the CTMU are cleared. This
leaves the CTMU module disabled, its current source is
turned off and all configuration options return to their
default settings. The module needs to be re-initialized
following any Reset.
There are three control registers for the CTMU:
If the CTMU is in the process of taking a measurement at
the time of Reset, the measurement will be lost. A partial
charge may exist on the circuit that was being measured,
and should be properly discharged before the CTMU
makes subsequent attempts to make a measurement.
The circuit is discharged by setting and then clearing the
IDISSEN bit (CTMUCONH<1>) while the A/D Converter
is connected to the appropriate channel.
The CTMUCONH and CTMUCONL registers
(Register 19-1 and Register 19-2) contain control bits
for configuring the CTMU module edge source selection, edge source polarity selection, edge sequencing,
A/D trigger, analog circuit capacitor discharge and
enables. The CTMUICON register (Register 19-3) has
bits for selecting the current source range and current
source trim.
REGISTER 19-1:
• CTMUCONH
• CTMUCONL
• CTMUICON
CTMUCONH: CTMU CONTROL REGISTER 0
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
U-0
CTMUEN
—
CTMUSIDL
TGEN
EDGEN
EDGSEQEN
IDISSEN
CTTRIG
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
CTMUEN: CTMU Enable bit
1 = Module is enabled
0 = Module is disabled
bit 6
Unimplemented: Read as ‘0’
bit 5
CTMUSIDL: Stop in Idle Mode bit
1 = Discontinue module operation when device enters Idle mode
0 = Continue module operation in Idle mode
bit 4
TGEN: Time Generation Enable bit
1 = Enables edge delay generation
0 = Disables edge delay generation
bit 3
EDGEN: Edge Enable bit
1 = Edges are not blocked
0 = Edges are blocked
bit 2
EDGSEQEN: Edge Sequence Enable bit
1 = Edge 1 event must occur before Edge 2 event can occur
0 = No edge sequence is needed
bit 1
IDISSEN: Analog Current Source Control bit
1 = Analog current source output is grounded
0 = Analog current source output is not grounded
bit 0
CTTRIG: CTMU Special Event Trigger Control Bit
1 = CTMU Special Event Trigger is enabled
0 = CTMU Special Event Trigger is disabled
 2010 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41412C-page 329
PIC18(L)F2X/4XK22
REGISTER 19-2:
R/W-0
CTMUCONL: CTMU CONTROL REGISTER 1
R/W-0
EDG2POL
R/W-0
EDG2SEL<1:0>
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
EDG1POL
EDG1SEL1
EDG1SEL0
EDG2STAT
EDG1STAT
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
EDG2POL: Edge 2 Polarity Select bit
1 = Edge 2 programmed for a positive edge response
0 = Edge 2 programmed for a negative edge response
bit 6-5
EDG2SEL<1:0>: Edge 2 Source Select bits
11 = CTED1 pin
10 = CTED2 pin
01 = ECCP1 Special Event Trigger
00 = ECCP2 Special Event Trigger
bit 4
EDG1POL: Edge 1 Polarity Select bit
1 = Edge 1 programmed for a positive edge response
0 = Edge 1 programmed for a negative edge response
bit 3-2
EDG1SEL<1:0>: Edge 1 Source Select bits
11 = CTED1 pin
10 = CTED2 pin
01 = ECCP1 Special Event Trigger
00 = ECCP2 Special Event Trigger
bit 1
EDG2STAT: Edge 2 Status bit
1 = Edge 2 event has occurred
0 = Edge 2 event has not occurred
bit 0
EDG1STAT: Edge 1 Status bit
1 = Edge 1 event has occurred
0 = Edge 1 event has not occurred
DS41412C-page 330
Preliminary
x = Bit is unknown
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 19-3:
R/W-0
CTMUICON: CTMU CURRENT CONTROL REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
ITRIM<5:0>
R/W-0
IRNG<1:0>
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 7-2
ITRIM<5:0>: Current Source Trim bits
011111 = Maximum positive change from nominal current
011110
.
.
.
000001 = Minimum positive change from nominal current
000000 = Nominal current output specified by IRNG<1:0>
111111 = Minimum negative change from nominal current
.
.
.
100010
100001 = Maximum negative change from nominal current
bit 1-0
IRNG<1:0>: Current Source Range Select bits
11 = 100  Base current
10 = 10  Base current
01 = Base current level (0.55 A nominal)
00 = Current source disabled
TABLE 19-1:
Name
x = Bit is unknown
REGISTERS ASSOCIATED WITH CTMU MODULE
Bit 7
Bit 6
Bit 5
CTMUSIDL
CTMUCONH
CTMUEN
—
CTMUCONL
EDG2POL
EDG2SEL<1:0>
CTMUICON
Bit 4
Bit 3
Bit 2
TGEN
EDGEN
EDGSEQEN
EDG1POL
EDG1SEL<1:0>
ITRIM<5:0>
Bit 0
Reset
Values
on Page
IDISSEN
CTTRIG
329
EDG2STAT
EDG1STAT
330
Bit 1
IRNG<1:0>
331
IPR3
SSP2IP
BCL2IP
RC2IP
TX2IP
CTMUIP
TMR5GIP
TMR3GIP
TMR1GIP
PIE3
SSP2IE
BCL2IE
RC2IE
TX2IE
CTMUIE
TMR5GIE
TMR3GIE
TMR1GIE
125
PIR3
SSP2IF
BCL2IF
RC2IF
TX2IF
CTMUIF
TMR5GIF
TMR3GIF
TMR1GIF
120
PMD2
—
—
—
—
CTMUMD
CMP2MD
CMP1MD
ADCMD
58
Legend:
129
— = unimplemented, read as ‘0’. Shaded bits are not used during CTMU operation.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 331
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 332
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
20.0
SR LATCH
20.2
The module consists of a single SR Latch with multiple
Set and Reset inputs as well as separate latch outputs.
The SR Latch module includes the following features:
•
•
•
•
Programmable input selection
SR Latch output is available internally/externally
Selectable Q and Q output
Firmware Set and Reset
Latch Operation
The latch is a Set-Reset Latch that does not depend on
a clock source. Each of the Set and Reset inputs are
active-high. The latch can be set or reset by:
•
•
•
•
•
The SRQEN and SRNQEN bits of the SRCON0 register
control the Q and Q latch outputs. Both of the SR Latch
outputs may be directly output to I/O pins at the same
time. Control is determined by the state of bits SRQEN
and SRNQEN in the SRCON0 register.
The applicable TRIS bit of the corresponding port must
be cleared to enable the port pin output driver.
The SR Latch can be used in a variety of analog
applications, including oscillator circuits, one-shot
circuit, hysteretic controllers, and analog timing
applications.
20.1
Latch Output
Software control (SRPS and SRPR bits)
Comparator C1 output (SYNCC1OUT)
Comparator C2 output (SYNCC2OUT)
SRI Pin
Programmable clock (DIVSRCLK)
20.3
DIVSRCLK Clock Generation
The DIVSRCLK clock signal is generated from the
peripheral clock which is pre-scaled by a value
determined by the SRCLK<2:0> bits. See Figure 20-2
and Table for additional detail.
20.4
Effects of a Reset
Upon any device Reset, the SR Latch is not initialized,
and the SRQ and SRNQ outputs are unknown. The
user’s firmware is responsible to initialize the latch
output before enabling it to the output pins.
The SRPS and the SRPR bits of the SRCON0 register
may be used to set or reset the SR Latch, respectively.
The latch is Reset-dominant. Therefore, if both Set and
Reset inputs are high, the latch will go to the Reset
state. Both the SRPS and SRPR bits are self resetting
which means that a single write to either of the bits is all
that is necessary to complete a latch Set or Reset
operation.
The output from Comparator C1 or C2 can be used as
the Set or Reset inputs of the SR Latch. The output of
either Comparator can be synchronized to the Timer1
clock source. See Section 18.0 “Comparator
Module” and Section 12.0 “Timer1/3/5 Module with
Gate Control” for more information.
An external source on the SRI pin can be used as the
Set or Reset inputs of the SR Latch.
An internal clock source, DIVSRCLK, is available and it
can periodically set or reset the SR Latch. The
SRCLK<2:0> bits in the SRCON0 register are used to
select the clock source period. The SRSCKE and
SRRCKE bits of the SRCON1 register enable the clock
source to set or reset the SR Latch, respectively.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 333
PIC18(L)F2X/4XK22
FIGURE 20-1:
DIVSRCLK BLOCK DIAGRAM
3
SRCLK<2:0>
Programmable
SRCLK divider
1:4 to 1:512
Peripheral
Clock
t0
t0+4
t0+8
DIVSRCLK
4-512 cycles
...
t0+12
Tosc
SRCLK<2:0> = "001"
1:8
FIGURE 20-2:
SR LATCH SIMPLIFIED BLOCK DIAGRAM
SRPS
SRLEN
Pulse
Gen(2)
SRQEN
SRI
S
SRSPE
DIVSRCLK
Q
SRQ
SRSCKE
SYNCC2OUT(3)
SRSC2E
SYNCC1OUT(3)
SRSC1E
SRPR
SR
Latch(1)
Pulse
Gen(2)
SRI
R
SRRPE
DIVSRCLK
Q
SRNQ
SRRCKE
SYNCC2OUT(3)
SRRC2E
SRLEN
SRNQEN
SYNCC1OUT(3)
SRRC1E
Note 1:
2:
3:
DS41412C-page 334
If R = 1 and S = 1 simultaneously, Q = 0, Q = 1
Pulse generator causes a pulse width of 2 TOSC clock cycles.
Name denotes the connection point at the comparator output.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 20-1:
DIVSRCLK FREQUENCY TABLE
SRCLK<2:0>
Divider
FOSC = 20 MHz
FOSC = 16 MHz
FOSC = 8 MHz FOSC = 4 MHz
FOSC = 1 MHz
111
512
25.6 s
32 s
64 s
128 s
512 s
110
256
12.8 s
16 s
32 s
64 s
256 s
101
128
6.4 s
8 s
16 s
32 s
128 s
100
64
3.2 s
4 s
8 s
16 s
64 s
011
32
1.6 s
2 s
4 s
8 s
32 s
010
16
0.8 s
1 s
2 s
4 s
16 s
001
8
0.4 s
0.5 s
1 s
2 s
8 s
000
4
0.2 s
0.25 s
0.5 s
1 s
4 s
REGISTER 20-1:
R/W-0
SRCON0: SR LATCH CONTROL REGISTER
R/W-0
SRLEN
R/W-0
R/W-0
SRCLK<2:0>
R/W-0
R/W-0
R/W-0
R/W-0
SRQEN
SRNQEN
SRPS
SRPR
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented
C = Clearable only bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SRLEN: SR Latch Enable bit(1)
1 = SR latch is enabled
0 = SR latch is disabled
bit 6-4
SRCLK<2:0>: SR Latch Clock Divider Bits
000 = Generates a 2 TOSC wide pulse on DIVSRCLK every 4 peripheral clock cycles
001 = Generates a 2 TOSC wide pulse on DIVSRCLK every 8 peripheral clock cycles
010 = Generates a 2 TOSC wide pulse on DIVSRCLK every 16 peripheral clock cycles
011 = Generates a 2 TOSC wide pulse on DIVSRCLK every 32 peripheral clock cycles
100 = Generates a 2 TOSC wide pulse on DIVSRCLK every 64 peripheral clock cycles
101 = Generates a 2 TOSC wide pulse on DIVSRCLK every 128 peripheral clock cycles
110 = Generates a 2 TOSC wide pulse on DIVSRCLK every 256 peripheral clock cycles
111 = Generates a 2 TOSC wide pulse on DIVSRCLK every 512 peripheral clock cycles
bit 3
SRQEN: SR Latch Q Output Enable bit
1 = Q is present on the SRQ pin
0 = Q is internal only
bit 2
SRNQEN: SR Latch Q Output Enable bit
1 = Q is present on the SRNQ pin
0 = Q is internal only
bit 1
SRPS: Pulse Set Input of the SR Latch bit(2)
1 = Pulse set input for 2 TOSC clock cycles
0 = No effect on set input
bit 0
SRPR: Pulse Reset Input of the SR Latch bit(2)
1 = Pulse reset input for 2 TOSC clock cycles
0 = No effect on Reset input
Note 1:
2:
Changing the SRCLK bits while the SR latch is enabled may cause false triggers to the set and Reset
inputs of the latch.
Set only, always reads back ‘0’.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 335
PIC18(L)F2X/4XK22
REGISTER 20-2:
SRCON1: SR LATCH CONTROL 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
SRSPE
SRSCKE
SRSC2E
SRSC1E
SRRPE
SRRCKE
SRRC2E
SRRC1E
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented
C = Clearable only bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SRSPE: SR Latch Peripheral Set Enable bit
1 = SRI pin status sets SR Latch
0 = SRI pin status has no effect on SR Latch
bit 6
SRSCKE: SR Latch Set Clock Enable bit
1 = Set input of SR latch is pulsed with DIVSRCLK
0 = Set input of SR latch is not pulsed with DIVSRCLK
bit 5
SRSC2E: SR Latch C2 Set Enable bit
1 = C2 Comparator output sets SR Latch
0 = C2 Comparator output has no effect on SR Latch
bit 4
SRSC1E: SR Latch C1 Set Enable bit
1 = C1 Comparator output sets SR Latch
0 = C1 Comparator output has no effect on SR Latch
bit 3
SRRPE: SR Latch Peripheral Reset Enable bit
1 = SRI pin resets SR Latch
0 = SRI pin has no effect on SR Latch
bit 2
SRRCKE: SR Latch Reset Clock Enable bit
1 = Reset input of SR latch is pulsed with DIVSRCLK
0 = Reset input of SR latch is not pulsed with DIVSRCLK
bit 1
SRRC2E: SR Latch C2 Reset Enable bit
1 = C2 Comparator output resets SR Latch
0 = C2 Comparator output has no effect on SR Latch
bit 0
SRRC1E: SR Latch C1 Reset Enable bit
1 = C1 Comparator output resets SR Latch
0 = C1 Comparator output has no effect on SR Latch
TABLE 20-2:
Name
REGISTERS ASSOCIATED WITH THE SR LATCH
Bit 7
Bit 6
Bit 5
SRCON0
SRLEN
SRCON1
SRSPE
SRSCKE
TRISA
TRISA7
TRISB
WPUB
Bit 4
SRCLK<2:0>
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
SRQEN
SRNQEN
SRPS
SRPR
335
SRSC2E SRSC1E
SRRPE
SRRCKE
SRRC2E
SRRC1E
336
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
154
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
155
Legend: Shaded bits are not used with this module.
DS41412C-page 336
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
21.0
FIXED VOLTAGE REFERENCE
(FVR)
The Fixed Voltage Reference, or FVR, is a stable
voltage reference, independent of VDD, with 1.024V,
2.048V or 4.096V selectable output levels. The output
of the FVR can be configured to supply a reference
voltage to the following:
•
•
•
•
ADC input channel
ADC positive reference
Comparator positive input
Digital-to-Analog Converter (DAC)
The FVR can be enabled by setting the FVREN bit of
the VREFCON0 register.
21.1
Independent Gain Amplifiers
The output of the FVR supplied to the ADC,
Comparators and DAC is routed through an
independent programmable gain amplifier. The
amplifier can be configured to amplify the 1.024V
reference voltage by 1x, 2x or 4x, to produce the three
possible voltage levels.
The FVRS<1:0> bits of the VREFCON0 register are
used to enable and configure the gain amplifier settings
for the reference supplied to the DAC and Comparator
modules. When the ADC module is configured to use
the FVR output, (FVR BUF2) the reference is buffered
through an additional unity gain amplifier. This buffer is
disabled if the ADC is not configured to use the FVR.
For specific use of the FVR, refer to the specific module
sections: Section 17.0 “Analog-to-Digital Converter
(ADC) Module”, Section 22.0 “Digital-to-Analog
Converter (DAC) Module” and Section 18.0 “Comparator Module”.
21.2
FVR Stabilization Period
When the Fixed Voltage Reference module is enabled, it
requires time for the reference and amplifier circuits to
stabilize. Once the circuits stabilize and are ready for use,
the FVRST bit of the VREFCON0 register will be set. See
Section 27.0 “Electrical Characteristics” for the
minimum delay requirement.
FIGURE 21-1:
VOLTAGE REFERENCE BLOCK DIAGRAM
X1
FVRS<1:0>
2
X1
X2
X4
FVREN
FVRST
 2010 Microchip Technology Inc.
FVR BUF2
(To ADC Module)
+
_
FVR BUF1
(To Comparators, DAC)
1.024V Fixed
Reference
Preliminary
DS41412C-page 337
PIC18(L)F2X/4XK22
REGISTER 21-1:
VREFCON0: FIXED VOLTAGE REFERENCE CONTROL REGISTER
R/W-0
R/W-0
FVREN
FVRST
R/W-0
R/W-1
U-0
U-0
U-0
U-0
—
—
—
—
FVRS<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
FVREN: Fixed Voltage Reference Enable bit
0 = Fixed Voltage Reference is disabled
1 = Fixed Voltage Reference is enabled
bit 6
FVRST: Fixed Voltage Reference Ready Flag bit
0 = Fixed Voltage Reference output is not ready or not enabled
1 = Fixed Voltage Reference output is ready for use
bit 5-4
FVRS<1:0>: Fixed Voltage Reference Selection bits
00 = Fixed Voltage Reference Peripheral output is off
01 = Fixed Voltage Reference Peripheral output is 1x (1.024V)
10 = Fixed Voltage Reference Peripheral output is 2x (2.048V)(1)
11 = Fixed Voltage Reference Peripheral output is 4x (4.096V)(1)
bit 3-2
Reserved: Read as ‘0’. Maintain these bits clear.
bit 1-0
Unimplemented: Read as ‘0’.
Note 1: Fixed Voltage Reference output cannot exceed VDD.
TABLE 21-1:
Name
VREFCON0
Legend:
SUMMARY OF REGISTERS ASSOCIATED WITH FIXED VOLTAGE REFERENCE
Bit 7
Bit 6
FVREN
FVRST
Bit 5
Bit 4
FVRS<1:0>
Bit 3
Bit 2
Bit 1
Bit 0
Register
on Page
—
—
—
—
338
— = unimplemented locations, read as ‘0’. Shaded bits are not used by the FVR module.
DS41412C-page 338
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
22.0
DIGITAL-TO-ANALOG
CONVERTER (DAC) MODULE
The Digital-to-Analog Converter supplies a variable
voltage reference, ratiometric with the input source,
with 32 selectable output levels.
The negative voltage source is disabled by setting the
DACLPS bit in the VREFCON1 register. Clearing the
DACLPS bit in the VREFCON1 register disables the
positive voltage source.
22.4
The input of the DAC can be connected to:
Output Clamped to Positive
Voltage Source
• External VREF pins
• VDD supply voltage
• FVR (Fixed Voltage Reference)
The DAC output voltage can be set to VSRC+ with the
least amount of power consumption by performing the
following:
The output of the DAC can be configured to supply a
reference voltage to the following:
• Clearing the DACEN bit in the VREFCON1
register.
• Setting the DACLPS bit in the VREFCON1
register.
• Configuring the DACPSS bits to the proper
positive source.
• Configuring the DACRx bits to ‘11111’ in the
VREFCON2 register.
• Comparator positive input
• ADC input channel
• DACOUT pin
The Digital-to-Analog Converter (DAC) can be enabled
by setting the DACEN bit of the VREFCON1 register.
22.1
Output Voltage Selection
The DAC has 32 voltage level ranges. The 32 levels
are set with the DACR<4:0> bits of the VREFCON2
register.
The DAC output voltage is determined by the following
equations:
EQUATION 22-1:
DAC OUTPUT VOLTAGE
2
VSRC+ = VDD, VREF+ or FVR1
VSRC- = VSS or VREF-
Ratiometric Output Level
The DAC output value is derived using a resistor ladder
with each end of the ladder tied to a positive and
negative voltage reference input source. If the voltage
of either input source fluctuates, a similar fluctuation will
result in the DAC output value.
The value of the individual resistors within the ladder
can be found in Section 27.0 “Electrical
Characteristics”.
22.3
Low-Power Voltage State
In order for the DAC module to consume the least
amount of power, one of the two voltage reference input
sources to the resistor ladder must be disconnected.
Either the positive voltage source, (VSRC+), or the
negative voltage source, (VSRC-) can be disabled.
 2010 Microchip Technology Inc.
22.5
Output Clamped to Negative
Voltage Source
The DAC output voltage can be set to VSRC- with the
least amount of power consumption by performing the
following:
• Clearing the DACEN bit in the VREFCON1
register.
• Clearing the DACLPS bit in the VREFCON1
register.
• Configuring the DACPSS bits to the proper
negative source.
• Configuring the DACRx bits to ‘00000’ in the
VREFCON2 register.
DACR<4:0>
VOUT =   VSRC+ – VSRC-   ------------------------------- + VSRC5
22.2
This is also the method used to output the voltage level
from the FVR to an output pin. See Section 22.6 “DAC
Voltage Reference Output” for more information.
This allows the comparator to detect a zero-crossing
while not consuming additional current through the DAC
module.
22.6
DAC Voltage Reference Output
The DAC can be output to the DACOUT pin by setting
the DACOE bit of the VREFCON1 register to ‘1’.
Selecting the DAC reference voltage for output on the
DACOUT pin automatically overrides the digital output
buffer and digital input threshold detector functions of
that pin. Reading the DACOUT pin when it has been
configured for DAC reference voltage output will always
return a ‘0’.
Due to the limited current drive capability, a buffer must
be used on the DAC voltage reference output for
external connections to DACOUT. Figure 22-2 shows
an example buffering technique.
Preliminary
DS41412C-page 339
PIC18(L)F2X/4XK22
FIGURE 22-1:
DIGITAL-TO-ANALOG CONVERTER BLOCK DIAGRAM
Digital-to-Analog Converter (DAC)
Reserved
11
10
FVR BUF1
VREF+
VSRC+
01
00
VDD
DACR<4:0>
5
R
2
R
DACPSS<1:0>
R
DACEN
DACLPS
11111
11110
R
32
Steps
R
32-to-1 MUX
R
R
R
00001
00000
DACNSS
FIGURE 22-2:
VREF-
1
VSS
0
DAC
(To Comparator, CSM and
ADC Modules)
DACOUT
DACOE
VSRC-
VOLTAGE REFERENCE OUTPUT BUFFER EXAMPLE
PIC® MCU
DAC
Module
R
Voltage
Reference
Output
Impedance
DS41412C-page 340
DACOUT
Preliminary
+
–
Buffered DAC Output
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
22.7
Operation During Sleep
22.8
When the device wakes up from Sleep through an
interrupt or a Watchdog Timer time-out, the contents of
the VREFCON1 register are not affected. To minimize
current consumption in Sleep mode, the voltage
reference should be disabled.
REGISTER 22-1:
Effects of a Reset
A device Reset affects the following:
• DAC is disabled
• DAC output voltage is removed from the
DACOUT pin
• The DAC1R<4:0> range select bits are cleared
VREFCON1: VOLTAGE REFERENCE CONTROL REGISTER 0
R/W-0
R/W-0
R/W-0
U-0
DACEN
DACLPS
DACOE
—
R/W-0
R/W-0
U-0
R/W-0
—
DACNSS
DACPSS<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
DACEN: DAC Enable bit
1 = DAC is enabled
0 = DAC is disabled
bit 6
DACLPS: DAC Low-Power Voltage Source Select bit
1 = DAC Positive reference source selected
0 = DAC Negative reference source selected
bit 5
DACOE: DAC Voltage Output Enable bit
1 = DAC voltage level is also an output on the DACOUT pin
0 = DAC voltage level is disconnected from the DACOUT pin
bit 4
Unimplemented: Read as ‘0’
bit 3-2
DACPSS<1:0>: DAC Positive Source Select bits
00 = VDD
01 = VREF+
10 = FVR BUF1 output
11 = Reserved, do not use
bit 1
Unimplemented: Read as ‘0’
bit 0
DACNSS: DAC Negative Source Select bits
1 = VREF0 = VSS
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 341
PIC18(L)F2X/4XK22
REGISTER 22-2:
VREFCON2: VOLTAGE REFERENCE CONTROL REGISTER 1
U-0
U-0
U-0
—
—
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
DACR<4:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
u = Bit is unchanged
x = Bit is unknown
-n/n = Value at POR and BOR/Value at all other Resets
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-5
Unimplemented: Read as ‘0’
bit 4-0
DACR<4:0>: DAC Voltage Output Select bits
VOUT = ((VSRC+) - (VSRC-))*(DACR<4:0>/(25)) + VSRC-
TABLE 22-1:
Name
REGISTERS ASSOCIATED WITH DAC MODULE
Bit 7
Bit 6
Bit 5
VREFCON0
FVREN
FVRST
VREFCON1
DACEN
DACLPS
DACOE
VREFCON2
—
—
—
Legend:
Bit 4
FVRS<1:0>
—
Bit 2
Bit 1
—
—
—
—
338
DACPSS<1:0>
—
DACNSS
341
DACR<4:0>
Bit 0
Register
on Page
Bit 3
342
— = Unimplemented locations, read as ‘0’. Shaded bits are not used by the DAC module.
DS41412C-page 342
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
23.0
HIGH/LOW-VOLTAGE DETECT
(HLVD)
The PIC18(L)F2X/4XK22 devices have a High/Low-Voltage Detect module (HLVD). This is a programmable circuit that sets both a device voltage trip point and the
direction of change from that point. If the device experiences an excursion past the trip point in that direction, an
interrupt flag is set. If the interrupt is enabled, the program execution branches to the interrupt vector address
and the software responds to the interrupt.
REGISTER 23-1:
The High/Low-Voltage Detect Control register
(Register 23-1) completely controls the operation of the
HLVD module. This allows the circuitry to be “turned
off” by the user under software control, which
minimizes the current consumption for the device.
The module’s block diagram is shown in Figure 23-1.
HLVDCON: HIGH/LOW-VOLTAGE DETECT CONTROL REGISTER
R/W-0
R-0
R-0
R/W-0
VDIRMAG
BGVST
IRVST
HLVDEN
R/W-0
R/W-1
R/W-0
R/W-1
HLVDL<3:0>
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
VDIRMAG: Voltage Direction Magnitude Select bit
1 = Event occurs when voltage equals or exceeds trip point (HLVDL<3:0>)
0 = Event occurs when voltage equals or falls below trip point (HLVDL<3:0>)
bit 6
BGVST: Band Gap Reference Voltages Stable Status Flag bit
1 = Internal band gap voltage references are stable
0 = Internal band gap voltage reference is not stable
bit 5
IRVST: Internal Reference Voltage Stable Flag bit
1 = Indicates that the voltage detect logic will generate the interrupt flag at the specified voltage range
0 = Indicates that the voltage detect logic will not generate the interrupt flag at the specified voltage
range and the HLVD interrupt should not be enabled
bit 4
HLVDEN: High/Low-Voltage Detect Power Enable bit
1 = HLVD enabled
0 = HLVD disabled
bit 3-0
HLVDL<3:0>: Voltage Detection Level bits(1)
1111 = External analog input is used (input comes from the HLVDIN pin)
1110 = Maximum setting
.
.
.
0000 = Minimum setting
Note 1:
See Table 27-4 for specifications.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 343
PIC18(L)F2X/4XK22
The module is enabled by setting the HLVDEN bit
(HLVDCON<4>). Each time the HLVD module is
enabled, the circuitry requires some time to stabilize.
The IRVST bit (HLVDCON<5>) is a read-only bit used
to indicate when the circuit is stable. The module can
only generate an interrupt after the circuit is stable and
IRVST is set.
trip point voltage. The “trip point” voltage is the voltage
level at which the device detects a high or low-voltage
event, depending on the configuration of the module.
When the supply voltage is equal to the trip point, the
voltage tapped off of the resistor array is equal to the
internal reference voltage generated by the voltage
reference module. The comparator then generates an
interrupt signal by setting the HLVDIF bit.
The VDIRMAG bit (HLVDCON<7>) determines the
overall operation of the module. When VDIRMAG is
cleared, the module monitors for drops in VDD below a
predetermined set point. When the bit is set, the
module monitors for rises in VDD above the set point.
23.1
The trip point voltage is software programmable to any of
16 values. The trip point is selected by programming the
HLVDL<3:0> bits (HLVDCON<3:0>).
The HLVD module has an additional feature that allows
the user to supply the trip voltage to the module from an
external source. This mode is enabled when bits,
HLVDL<3:0>, are set to ‘1111’. In this state, the
comparator input is multiplexed from the external input
pin, HLVDIN. This gives users the flexibility of configuring the High/Low-Voltage Detect interrupt to occur at
any voltage in the valid operating range.
Operation
When the HLVD module is enabled, a comparator uses
an internally generated reference voltage as the set
point. The set point is compared with the trip point,
where each node in the resistor divider represents a
FIGURE 23-1:
VDD
HLVD MODULE BLOCK DIAGRAM (WITH EXTERNAL INPUT)
Externally Generated
Trip Point
VDD
HLVDL<3:0>
HLVDCON
Register
HLVDEN
HLVDIN
VDIRMAG
16-to-1 MUX
Set
HLVDIF
HLVDEN
BOREN
DS41412C-page 344
Internal Voltage
Reference
1.024V Typical
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
23.2
HLVD Setup
23.3
To set up the HLVD module:
1.
2.
3.
4.
5.
When the module is enabled, the HLVD comparator
and voltage divider are enabled and consume static
current. The total current consumption, when enabled,
is specified in Section 27.0 “Electrical Characteristics”. Depending on the application, the HLVD module
does not need to operate constantly. To reduce current
requirements, the HLVD circuitry may only need to be
enabled for short periods where the voltage is checked.
After such a check, the module could be disabled.
Select the desired HLVD trip point by writing the
value to the HLVDL<3:0> bits.
Set the VDIRMAG bit to detect high voltage
(VDIRMAG = 1) or low voltage (VDIRMAG = 0).
Enable the HLVD module by setting the
HLVDEN bit.
Clear the HLVD interrupt flag (PIR2<2>), which
may have been set from a previous interrupt.
If interrupts are desired, enable the HLVD
interrupt by setting the HLVDIE and GIE/GIEH
bits (PIE2<2> and INTCON<7>, respectively).
23.4
HLVD Start-up Time
The internal reference voltage of the HLVD module,
specified
in
Section 27.0
“Electrical
Characteristics”, may be used by other internal
circuitry, such as the programmable Brown-out Reset.
If the HLVD or other circuits using the voltage reference
are disabled to lower the device’s current consumption,
the reference voltage circuit will require time to become
stable before a low or high-voltage condition can be
reliably detected. This start-up time, TIRVST, is an
interval that is independent of device clock speed.
An interrupt will not be generated until the
IRVST bit is set.
Note:
Current Consumption
Before changing any module settings
(VDIRMAG, HLVDL<3:0>), first disable the
module (HLVDEN = 0), make the changes
and re-enable the module. This prevents
the generation of false HLVD events.
The HLVD interrupt flag is not enabled until TIRVST has
expired and a stable reference voltage is reached. For
this reason, brief excursions beyond the set point may
not be detected during this interval (see Figure 23-2 or
Figure 23-3).
FIGURE 23-2:
LOW-VOLTAGE DETECT OPERATION (VDIRMAG = 0)
CASE 1:
HLVDIF may not be set
VDD
VHLVD
HLVDIF
Enable HLVD
TIRVST
IRVST
Internal Reference is stable
CASE 2:
HLVDIF cleared in software
VDD
VHLVD
HLVDIF
Enable HLVD
TIRVST
IRVST
HLVDIF cleared in software
Internal Reference is stable
HLVDIF cleared in software,
HLVDIF remains set since HLVD condition still exists
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 345
PIC18(L)F2X/4XK22
FIGURE 23-3:
HIGH-VOLTAGE DETECT OPERATION (VDIRMAG = 1)
CASE 1:
HLVDIF may not be set
VHLVD
VDD
HLVDIF
Enable HLVD
TIRVST
IRVST
HLVDIF cleared in software
Internal Reference is stable
CASE 2:
VHLVD
VDD
HLVDIF
Enable HLVD
TIRVST
IRVST
Internal Reference is stable
HLVDIF cleared in software
HLVDIF cleared in software,
HLVDIF remains set since HLVD condition still exists
Applications
FIGURE 23-4:
In many applications, it is desirable to detect a drop
below, or rise above, a particular voltage threshold. For
example, the HLVD module could be periodically
enabled to detect Universal Serial Bus (USB) attach or
detach. This assumes the device is powered by a lower
voltage source than the USB when detached. An attach
would indicate a high-voltage detect from, for example,
3.3V to 5V (the voltage on USB) and vice versa for a
detach. This feature could save a design a few extra
components and an attach signal (input pin).
VA
VB
For general battery applications, Figure 23-4 shows a
possible voltage curve. Over time, the device voltage
decreases. When the device voltage reaches voltage
VA, the HLVD logic generates an interrupt at time, TA.
The interrupt could cause the execution of an ISR,
which would allow the application to perform “housekeeping tasks” and a controlled shutdown before the
device voltage exits the valid operating range at TB.
This would give the application a time window,
represented by the difference between TA and TB, to
safely exit.
DS41412C-page 346
TYPICAL LOW-VOLTAGE
DETECT APPLICATION
Voltage
23.5
Preliminary
Time
TA
TB
Legend: VA = HLVD trip point
VB = Minimum valid device
operating voltage
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
23.6
Operation During Sleep
23.7
When enabled, the HLVD circuitry continues to operate
during Sleep. If the device voltage crosses the trip
point, the HLVDIF bit will be set and the device will
wake-up from Sleep. Device execution will continue
from the interrupt vector address if interrupts have
been globally enabled.
TABLE 23-1:
Effects of a Reset
A device Reset forces all registers to their Reset state.
This forces the HLVD module to be turned off.
REGISTERS ASSOCIATED WITH HIGH/LOW-VOLTAGE DETECT MODULE
Name
Bit 7
Bit 6
Bit 5
Bit 4
HLVDCON
VDIRMAG
BGVST
IRVST
HLVDEN
INTCON
GIE/GIEH PEIE/GIEL
Bit 3
Bit 2
Bit 1
Bit 0
HLVDL<3:0>
Reset
Values
on page
343
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
115
IPR2
OSCFIP
C1IP
C2IP
EEIP
BCL1IP
HLVDIP
TMR3IP
CCP2IP
128
PIE2
OSCFIE
C1IE
C2IE
EEIE
BCL1IE
HLVDIE
TMR3IE
CCP2IE
124
PIR2
OSCFIF
C1IF
C2IF
EEIF
BCL1IF
HLVDIF
TMR3IF
CCP2IF
119
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
154
Legend: — = unimplemented locations, read as ‘0’. Shaded bits are unused by the HLVD module.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 347
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 348
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
24.0
SPECIAL FEATURES OF
THE CPU
24.1
PIC18(L)F2X/4XK22 devices include several features
intended to maximize reliability and minimize cost through
elimination of external components. These are:
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.
The user will note that address 300000h is beyond the
user program memory space. In fact, it belongs to the
configuration memory space (300000h-3FFFFFh), which
can only be accessed using table reads and table writes.
• Oscillator Selection
• Resets:
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• Code Protection
• ID Locations
• In-Circuit Serial Programming™
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 2.0
“Oscillator Module (With Fail-Safe Clock Monitor)”.
Programming the Configuration registers is done in a
manner similar to programming the Flash memory. The
WR bit in the EECON1 register starts a self-timed write
to the Configuration register. In normal operation mode,
a TBLWT instruction with the TBLPTR pointing to the
Configuration register sets up the address and the data
for the Configuration register write. Setting the WR bit
starts a long write to the Configuration register. The
Configuration registers are written a byte at a time. To
write or erase a configuration cell, a TBLWT instruction
can write a ‘1’ or a ‘0’ into the cell. For additional details
on Flash programming, refer to Section 6.5 “Writing
to Flash Program Memory”.
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, PIC18(L)F2X/4XK22
devices have a Watchdog Timer, which is either
permanently enabled via the Configuration bits or
software controlled (if configured as disabled).
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. TwoSpeed 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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 349
PIC18(L)F2X/4XK22
TABLE 24-1:
Address
CONFIGURATION BITS AND DEVICE IDs
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Default/
Unprogrammed
Value
—
—
—
—
0000 0000
300000h
CONFIG1L
—
—
—
—
300001h
CONFIG1H
IESO
FCMEN
PRICLKEN
PLLCFG
300002h
CONFIG2L
—
—
—
300003h
CONFIG2H
—
—
300004h
CONFIG3L
—
—
—
—
—
300005h
CONFIG3H
MCLRE
—
P2BMX
T3CMX
HFOFST
300006h
CONFIG4L
DEBUG
XINST
—
—
—
LVP(1)
—
STRVEN
1000 0101
300007h
CONFIG4H
—
—
—
—
—
—
—
—
1111 1111
300008h
CONFIG5L
—
—
—
—
CP3(2)
CP2(2)
CP1
CP0
0000 1111
300009h
CONFIG5H
CPD
CPB
—
—
—
—
—
—
1100 0000
30000Ah
CONFIG6L
—
—
—
—
WRT3(2)
WRT2(2)
WRT1
WRT0
0000 1111
30000Bh
CONFIG6H
WRTD
WRTB
WRTC(3)
—
—
—
—
—
1110 0000
30000Ch
CONFIG7L
—
—
—
—
EBTR3(2)
EBTR2(2)
EBTR1
EBTR0
0000 1111
—
EBTRB
—
—
—
—
—
—
0100 0000
FOSC<3:0>
BORV<1:0>
BOREN<1:0>
WDPS<3:0>
—
0010 0101
PWRTEN
0001 1111
WDTEN<1:0>
0011 1111
—
0000 0000
—
CCP3MX PBADEN CCP2MX
1011 1111
30000Dh
CONFIG7H
3FFFFEh
DEVID1(4)
3FFFFFh
DEVID2(4)
Legend:
Note 1:
2:
3:
4:
– = unimplemented, q = value depends on condition. Shaded bits are unimplemented, read as '0'.
Can only be changed when in high voltage programming mode.
Available on PIC18(L)FX5K22 and PIC18(L)FX6K22 devices only.
In user mode, this bit is read-only and cannot be self-programmed.
See Register 24-12 and Register 24-13 for DEVID values. DEVID registers are read-only and cannot be programmed by the
user.
DS41412C-page 350
DEV<2:0>
REV<4:0>
DEV<10:3>
Preliminary
qqqq qqqq
0101 qqqq
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 24-1:
CONFIG1H: CONFIGURATION REGISTER 1 HIGH
R/P-0
R/P-0
R/P-1
R/P-0
IESO
FCMEN
PRICLKEN
PLLCFG
R/P-0
R/P-1
R/P-0
R/P-1
FOSC<3:0>
bit 7
bit 0
Legend:
R = Readable bit
P = Programmable bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
x = Bit is unknown
bit 7
IESO(1): Internal/External Oscillator Switchover bit
1 = Oscillator Switchover mode enabled
0 = Oscillator Switchover mode disabled
bit 6
FCMEN(1): Fail-Safe Clock Monitor Enable bit
1 = Fail-Safe Clock Monitor enabled
0 = Fail-Safe Clock Monitor disabled
bit 5
PRICLKEN: Primary Clock Enable bit
1 = Primary Clock is always enabled
0 = Primary Clock can be disabled by software
bit 4
PLLCFG: 4 x PLL Enable bit
1 = 4 x PLL always enabled, Oscillator multiplied by 4
0 = 4 x PLL is under software control, PLLEN (OSCTUNE<6>)
bit 3-0
FOSC<3:0>: Oscillator Selection bits
1111 = External RC oscillator, CLKOUT function on RA6
1110 = External RC oscillator, CLKOUT function on RA6
1101 = EC oscillator (low power, <500 kHz)
1100 = EC oscillator, CLKOUT function on OSC2 (low power, <500 kHz)
1011 = EC oscillator (medium power, 500 kHz-16 MHz)
1010 = EC oscillator, CLKOUT function on OSC2 (medium power, 500 kHz-16 MHz)
1001 = Internal oscillator block, CLKOUT function on OSC2
1000 = Internal oscillator block
0111 = External RC oscillator
0110 = External RC oscillator, CLKOUT function on OSC2
0101 = EC oscillator (high power, >16 MHz)
0100 = EC oscillator, CLKOUT function on OSC2 (high power, >16 MHz)
0011= HS oscillator (medium power, 4 MHz-16 MHz)
0010= HS oscillator (high power, >16 MHz)
0001= XT oscillator
0000= LP oscillator
Note 1:
When FOSC<3:0> is configured for HS, XT, or LP oscillator and FCMEN bit is set, then the IESO bit
should also be set to prevent a false failed clock indication and to enable automatic clock switch over from
the internal oscillator block to the external oscillator when the OST times out.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 351
PIC18(L)F2X/4XK22
REGISTER 24-2:
CONFIG2L: CONFIGURATION REGISTER 2 LOW
U-0
U-0
U-0
—
—
—
R/P-1
R/P-1
BORV<1:0>(1)
R/P-1
R/P-1
BOREN<1:0>(2)
R/P-1
PWRTEN(2)
bit 7
bit 0
Legend:
R = Readable bit
P = Programmable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
x = Bit is unknown
bit 7-5
Unimplemented: Read as ‘0’
bit 4-3
BORV<1:0>: Brown-out Reset Voltage bits(1)
11 = VBOR set to 1.9V nominal
10 = VBOR set to 2.2V nominal
01 = VBOR set to 2.5V nominal
00 = VBOR set to 2.85V nominal
bit 2-1
BOREN<1:0>: Brown-out Reset Enable bits(2)
11 = Brown-out Reset enabled in hardware only (SBOREN is disabled)
10 = Brown-out Reset enabled in hardware only and disabled in Sleep mode
(SBOREN is disabled)
01 = Brown-out Reset enabled and controlled by software (SBOREN is enabled)
00 = Brown-out Reset disabled in hardware and software
bit 0
PWRTEN: Power-up Timer Enable bit(2)
1 = PWRT disabled
0 = PWRT enabled
Note
1:
2:
See Section 27.1 “DC Characteristics: Supply Voltage, PIC18(L)F2X/4XK22” for specifications.
The Power-up Timer is decoupled from Brown-out Reset, allowing these features to be independently controlled.
DS41412C-page 352
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 24-3:
CONFIG2H: CONFIGURATION REGISTER 2 HIGH
U-0
U-0
—
—
R/P-1
R/P-1
R/P-1
R/P-1
WDTPS<3:0>
R/P-1
R/P-1
WDTEN<1:0>
bit 7
bit 0
Legend:
R = Readable bit
P = Programmable bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
x = Bit is unknown
bit 7-6
Unimplemented: Read as ‘0’
bit 5-2
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
bit 1-0
WDTEN<1:0>: Watchdog Timer Enable bits
11 = WDT enabled in hardware; SWDTEN bit disabled
10 = WDT controlled by the SWDTEN bit
01 = WDT enabled when device is active, disabled when device is in Sleep; SWDTEN bit disabled
00 = WDT disabled in hardware; SWDTEN bit disabled
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 353
PIC18(L)F2X/4XK22
REGISTER 24-4:
CONFIG3H: CONFIGURATION REGISTER 3 HIGH
R/P-1
U-0
R/P-1
R/P-1
R/P-1
R/P-1
R/P-1
R/P-1
MCLRE
—
P2BMX
T3CMX
HFOFST
CCP3MX
PBADEN
CCP2MX
bit 7
bit 0
Legend:
R = Readable bit
P = Programmable bit
-n = Value when device is unprogrammed
U = Unimplemented bit, read as ‘0’
x = Bit is unknown
bit 7
MCLRE: MCLR Pin Enable bit
1 = MCLR pin enabled; RE3 input pin disabled
0 = RE3 input pin enabled; MCLR disabled
bit 6
Unimplemented: Read as ‘0’
bit 5
P2BMX: P2B Input MUX bit
1 = P2B is on RB5(1)
P2B is on RD2(2)
0 = P2B is on RC0
bit 4
T3CMX: Timer3 Clock Input MUX bit
1 = T3CKI is on RC0
0 = T3CKI is on RB5
bit 3
HFOFST: HFINTOSC Fast Start-up bit
1 = HFINTOSC starts clocking the CPU without waiting for the oscillator to stabilize
0 = The system clock is held off until the HFINTOSC is stable
bit 2
CCP3MX: CCP3 MUX bit
1 = CCP3 input/output is multiplexed with RB5
0 = CCP3 input/output is multiplexed with RC6(1)
CCP3 input/output is multiplexed with RE0(2)
bit 1
PBADEN: PORTB A/D Enable bit
1 = ANSELB<5:0> resets to 1, PORTB<5:0> pins are configured as analog inputs on Reset
0 = ANSELB<5:0> resets to 0, PORTB<4:0> pins are configured as digital I/O on Reset
bit 0
CCP2MX: CCP2 MUX bit
1 = CCP2 input/output is multiplexed with RC1
0 = CCP2 input/output is multiplexed with RB3
Note 1:
2:
PIC18(L)F2XK22 devices only.
PIC18(L)F4XK22 devices only.
DS41412C-page 354
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 24-5:
R/P-1
DEBUG
CONFIG4L: CONFIGURATION REGISTER 4 LOW
R/P-0
(2)
XINST
U-0
U-0
—
—
U-0
—
R/P-1
LVP
(1)
U-0
R/P-1
—
STVREN
bit 0
bit 7
Legend:
R = Readable bit
P = Programmable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
x = Bit is unknown
bit 7
DEBUG: Background Debugger Enable bit(2)
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 5-3
Unimplemented: Read as ‘0’
bit 2
LVP: Single-Supply ICSP Enable bit
1 = Single-Supply ICSP enabled
0 = Single-Supply ICSP disabled
bit 1
Unimplemented: Read as ‘0’
bit 0
STVREN: Stack Full/Underflow Reset Enable bit
1 = Stack full/underflow will cause Reset
0 = Stack full/underflow will not cause Reset
Note 1:
2:
Can only be changed by a programmer in high-voltage programming mode.
The DEBUG bit is managed automatically by device development tools including debuggers and programmers. For
normal device operations, this bit should be maintained as a ‘1’.
REGISTER 24-6:
U-0
CONFIG5L: CONFIGURATION REGISTER 5 LOW
U-0
—
—
U-0
—
U-0
R/C-1
R/C-1
R/C-1
R/C-1
—
CP3(1)
CP2(1)
CP1
CP0
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7-4
Unimplemented: Read as ‘0’
bit 3
CP3: Code Protection bit(1)
1 = Block 3 not code-protected
0 = Block 3 code-protected
bit 2
CP2: Code Protection bit(1)
1 = Block 2 not code-protected
0 = Block 2 code-protected
bit 1
CP1: Code Protection bit
1 = Block 1 not code-protected
0 = Block 1 code-protected
bit 0
CP0: Code Protection bit
1 = Block 0 not code-protected
0 = Block 0 code-protected
Note 1:
Available on PIC18(L)FX5K22 and PIC18(L)FX6K22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 355
PIC18(L)F2X/4XK22
REGISTER 24-7:
CONFIG5H: CONFIGURATION REGISTER 5 HIGH
R/C-1
R/C-1
U-0
U-0
U-0
U-0
U-0
U-0
CPD
CPB
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7
CPD: Data EEPROM Code Protection bit
1 = Data EEPROM not code-protected
0 = Data EEPROM code-protected
bit 6
CPB: Boot Block Code Protection bit
1 = Boot Block not code-protected
0 = Boot Block code-protected
bit 5-0
Unimplemented: Read as ‘0’
REGISTER 24-8:
U-0
CONFIG6L: CONFIGURATION REGISTER 6 LOW
U-0
—
—
U-0
—
U-0
R/C-1
R/C-1
R/C-1
R/C-1
—
WRT3(1)
WRT2(1)
WRT1
WRT0
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7-4
Unimplemented: Read as ‘0’
bit 3
WRT3: Write Protection bit(1)
1 = Block 3 not write-protected
0 = Block 3 write-protected
bit 2
WRT2: Write Protection bit(1)
1 = Block 2 not write-protected
0 = Block 2 write-protected
bit 1
WRT1: Write Protection bit
1 = Block 1 not write-protected
0 = Block 1 write-protected
bit 0
WRT0: Write Protection bit
1 = Block 0 not write-protected
0 = Block 0 write-protected
Note 1:
Available on PIC18(L)FX5K22 and PIC18(L)FX6K22 devices.
DS41412C-page 356
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
REGISTER 24-9:
R/C-1
CONFIG6H: CONFIGURATION REGISTER 6 HIGH
R/C-1
WRTD
WRTB
R-1
(1)
WRTC
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7
WRTD: Data EEPROM Write Protection bit
1 = Data EEPROM not write-protected
0 = Data EEPROM write-protected
bit 6
WRTB: Boot Block Write Protection bit
1 = Boot Block not write-protected
0 = Boot Block write-protected
bit 5
WRTC: Configuration Register Write Protection bit(1)
1 = Configuration registers not write-protected
0 = Configuration registers write-protected
bit 4-0
Note 1:
Unimplemented: Read as ‘0’
This bit is read-only in normal execution mode; it can be written only in Program mode.
REGISTER 24-10: CONFIG7L: CONFIGURATION REGISTER 7 LOW
U-0
U-0
U-0
U-0
R/C-1
R/C-1
R/C-1
R/C-1
—
—
—
—
EBTR3(1)
EBTR2(1)
EBTR1
EBTR0
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7-4
Unimplemented: Read as ‘0’
bit 3
EBTR3: Table Read Protection bit(1)
1 = Block 3 not protected from table reads executed in other blocks
0 = Block 3 protected from table reads executed in other blocks
bit 2
EBTR2: Table Read Protection bit(1)
1 = Block 2 not protected from table reads executed in other blocks
0 = Block 2 protected from table reads executed in other blocks
bit 1
EBTR1: Table Read Protection bit
1 = Block 1 not protected from table reads executed in other blocks
0 = Block 1 protected from table reads executed in other blocks
bit 0
EBTR0: Table Read Protection bit
1 = Block 0 not protected from table reads executed in other blocks
0 = Block 0 protected from table reads executed in other blocks
Note 1:
Available on PIC18(L)FX5K22 and PIC18(L)FX6K22 devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 357
PIC18(L)F2X/4XK22
REGISTER 24-11: CONFIG7H: CONFIGURATION REGISTER 7 HIGH
U-0
R/C-1
U-0
U-0
U-0
U-0
U-0
U-0
—
EBTRB
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7
Unimplemented: Read as ‘0’
bit 6
EBTRB: Boot Block Table Read Protection bit
1 = Boot Block not protected from table reads executed in other blocks
0 = Boot Block protected from table reads executed in other blocks
bit 5-0
Unimplemented: Read as ‘0’
REGISTER 24-12: DEVID1: DEVICE ID REGISTER 1
R
R
R
R
R
R
R
R
DEV2
DEV1
DEV0
REV4
REV3
REV2
REV1
REV0
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7-5
DEV<2:0>: Device ID bits
These bits, together with DEV<10:3> in DEVID2, determine the device ID.
See Table 24-2 for complete Device ID list.
bit 4-0
REV<4:0>: Revision ID bits
These bits indicate the device revision.
REGISTER 24-13: DEVID2: DEVICE ID REGISTER 2
R
R
R
R
R
R
R
R
DEV10
DEV9
DEV8
DEV7
DEV6
DEV5
DEV4
DEV3
bit 7
bit 0
Legend:
R = Readable bit
U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed
C = Clearable only bit
bit 7-0
DEV<10:3>: Device ID bits
These bits, together with DEV<2:0> in DEVID1, determine the device ID.
See Table 24-2 for complete Device ID list.
DS41412C-page 358
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 24-2:
DEVICE ID TABLE FOR THE PIC18(L)F2X/4XK22 FAMILY
DEV<10:3>
0101 0100
0101 0101
0101 0110
0101 0111
 2010 Microchip Technology Inc.
DEV<2:0>
Part Number
000
PIC18F46K22
001
PIC18LF46K22
010
PIC18F26K22
011
PIC18LF26K22
000
PIC18F45K22
001
PIC18LF45K22
010
PIC18F25K22
011
PIC18LF25K22
000
PIC18F44K22
001
PIC18LF44K22
010
PIC18F24K22
011
PIC18LF24K22
000
PIC18F43K22
001
PIC18LF43K22
010
PIC18F23K22
011
PIC18LF23K22
Preliminary
DS41412C-page 359
PIC18(L)F2X/4XK22
24.2
Watchdog Timer (WDT)
For PIC18(L)F2X/4XK22 devices, the WDT is driven by
the LFINTOSC source. 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 LFINTOSC
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 multiplexer, controlled by bits in Configuration Register 2H. Available periods range from 4 ms
to 131.072 seconds (2.18 minutes). The WDT and
postscaler are cleared when any of the following events
occur: a SLEEP or CLRWDT instruction is executed, the
IRCF bits of the OSCCON register are changed or a
clock failure has occurred.
Note 1: The CLRWDT and SLEEP instructions
clear the WDT and postscaler counts
when executed.
2: Changing the setting of the IRCF bits of
the OSCCON register clears the WDT
and postscaler counts.
3: When a CLRWDT instruction is executed,
the postscaler count will be cleared.
FIGURE 24-1:
SWDTEN
WDTEN
WDT BLOCK DIAGRAM
Enable WDT
WDT Counter
LFINTOSC Source
Wake-up
from Power
Managed Modes
128
Change on IRCF bits
Programmable Postscaler
1:1 to 1:32,768
CLRWDT
Reset
WDT
Reset
All Device Resets
WDTPS<3:0>
4
Sleep
DS41412C-page 360
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
24.2.1
CONTROL REGISTER
Register 24-14 shows the WDTCON register. This is a
readable and writable register which contains a control
bit that allows software to override the WDT enable
Configuration bit, but only if the Configuration bit has
disabled the WDT.
REGISTER 24-14: 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 Enable or Disable the Watchdog Timer bit(1)
1 = WDT is turned on
0 = WDT is turned off (Reset value)
Note 1:
x = Bit is unknown
This bit has no effect if the Configuration bit, WDTEN, is enabled.
TABLE 24-3:
Name
RCON
WDTCON
REGISTERS ASSOCIATED WITH WATCHDOG TIMER
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on Page
IPEN
SBOREN
—
RI
TO
PD
POR
BOR
60
—
—
—
—
—
—
—
SWDTEN
361
Legend: — = unimplemented, read as ‘0’. Shaded bits are not used by the Watchdog Timer.
TABLE 24-4:
CONFIGURATION REGISTERS ASSOCIATED WITH WATCHDOG TIMER
Name
Bit 7
Bit 6
CONFIG2H
—
—
Bit 5
Bit 4
Bit 3
WDPS<3:0>
Bit 2
Bit 1
Bit 0
WDTEN<1:0>
Reset
Values
on Page
353
Legend: — = unimplemented, read as ‘0’. Shaded bits are not used by the Watchdog Timer.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 361
PIC18(L)F2X/4XK22
24.3
Program Verification and
Code Protection
Each of the blocks has three code protection bits associated with them. They are:
The overall structure of the code protection on the
PIC18 Flash devices differs significantly from other
PIC® microcontroller devices.
The user program memory is divided into three or five
blocks, depending on the device. One of these is a
Boot Block of 0.5K or 2K bytes, depending on the
device. The remainder of the memory is divided into
individual blocks on binary boundaries.
FIGURE 24-2:
• Code-Protect bit (CPn)
• Write-Protect bit (WRTn)
• External Block Table Read bit (EBTRn)
Figure 24-2 shows the program memory organization
for 8, 16 and 32-Kbyte devices and the specific code
protection bit associated with each block. The actual
locations of the bits are summarized in Table .
CODE-PROTECTED PROGRAM MEMORY FOR PIC18(L)F2X/4XK22
MEMORY SIZE/DEVICE
8 Kbytes
16 Kbytes
32 Kbytes
64 Kbytes
(PIC18(L)FX3K22) (PIC18(L)FX4K22) (PIC18(L)FX5K22) (PIC18(L)FX6K22)
Block Code Protection
Controlled By:
Boot Block
(000h-1FFh)
Boot Block
(000h-7FFh)
Boot Block
(000h-7FFh)
Boot Block
(000h-7FFh)
CPB, WRTB, EBTRB
Block 0
(200h-FFFh)
Block 0
(800h-1FFFh)
Block 0
(800h-1FFFh)
Block 0
(800h-3FFFh)
CP0, WRT0, EBTR0
Block 1
(1000h-1FFFh)
Block 1
(2000h-3FFFh)
Block 1
(2000h-3FFFh)
Block 1
(4000h-7FFFh)
CP1, WRT1, EBTR1
Block 2
(4000h-5FFFh)
Block 2
(8000h-BFFFh)
CP2, WRT2, EBTR2
Block 3
(6000h-7FFFh)
Block 3
(C000h-FFFFh)
CP3, WRT3, EBTR3
Unimplemented
Read ‘0’s
(2000h-1FFFFFh)
Unimplemented
Read ‘0’s
(4000h-1FFFFFh)
Unimplemented
Unimplemented
Read ‘0’s
Read ‘0’s
(8000h-1FFFFFh) (10000h-1FFFFFh)
TABLE 24-5:
(Unimplemented
Memory Space)
CONFIGURATION REGISTERS ASSOCIATED WITH CODE PROTECTION
File Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CP3(1)
CP2(1)
CP1
CP0
300008h
CONFIG5L
—
—
—
—
300009h
CONFIG5H
CPD
CPB
—
—
—
—
—
—
30000Ah
CONFIG6L
—
—
—
—
WRT3(1)
WRT2(1)
WRT1
WRT0
30000Bh
CONFIG6H
WRTD
WRTB
WRTC(2)
—
—
—
—
—
30000Ch
CONFIG7L
—
—
—
—
EBTR3(1)
EBTR2(1)
EBTR1
EBTR0
30000Dh
CONFIG7H
—
EBTRB
—
—
—
—
—
—
Legend: Shaded bits are unimplemented.
Note
1: Available on PIC18(L)FX5K22 and PIC18(L)FX6K22 devices only.
2: In user mode, this bit is read-only and cannot be self-programmed.
DS41412C-page 362
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
24.3.1
PROGRAM MEMORY
CODE PROTECTION
The program memory may be read to or written from
any location using the table read and table write
instructions. The device ID may be read with table
reads. The Configuration registers may be read and
written with the table read and table write instructions.
instruction that executes from a location outside of that
block is not allowed to read and will result in reading ‘0’s.
Figures 24-3 through 24-5 illustrate table write and table
read protection.
Note:
In normal execution mode, the CPn bits have no direct
effect. CPn bits inhibit external reads and writes. A block
of user memory may be protected from table writes if the
WRTn Configuration bit is ‘0’. The EBTRn bits control
table reads. For a block of user memory with the EBTRn
bit cleared to ‘0’, a table READ instruction that executes
from within that block is allowed to read. A table read
FIGURE 24-3:
Code protection bits may only be written to
a ‘0’ from a ‘1’ state. It is not possible to
write a ‘1’ to a bit in the ‘0’ state. Code protection bits are only set to ‘1’ by a full chip
erase or block erase function. The full chip
erase and block erase functions can only
be initiated via ICSP™ or an external
programmer.
TABLE WRITE (WRTn) DISALLOWED
Register Values
Program Memory
Configuration Bit Settings
000000h
0007FFh
000800h
TBLPTR = 0008FFh
PC = 001FFEh
WRTB, EBTRB = 11
WRT0, EBTR0 = 01
TBLWT*
001FFFh
002000h
WRT1, EBTR1 = 11
003FFFh
004000h
PC = 005FFEh
WRT2, EBTR2 = 11
TBLWT*
005FFFh
006000h
WRT3, EBTR3 = 11
007FFFh
Results: All table writes disabled to Blockn whenever WRTn = 0.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 363
PIC18(L)F2X/4XK22
FIGURE 24-4:
EXTERNAL BLOCK TABLE READ (EBTRn) DISALLOWED
Register Values
Program Memory
Configuration Bit Settings
000000h
0007FFh
000800h
TBLPTR = 0008FFh
WRTB, EBTRB = 11
WRT0, EBTR0 = 10
001FFFh
002000h
PC = 003FFEh
TBLRD*
WRT1, EBTR1 = 11
003FFFh
004000h
WRT2, EBTR2 = 11
005FFFh
006000h
WRT3, EBTR3 = 11
007FFFh
Results: All table reads from external blocks to Blockn are disabled whenever EBTRn = 0.
TABLAT register returns a value of ‘0’.
FIGURE 24-5:
EXTERNAL BLOCK TABLE READ (EBTRn) ALLOWED
Register Values
Program Memory
Configuration Bit Settings
000000h
0007FFh
000800h
TBLPTR = 0008FFh
PC = 001FFEh
WRTB, EBTRB = 11
WRT0, EBTR0 = 10
TBLRD*
001FFFh
002000h
WRT1, EBTR1 = 11
003FFFh
004000h
WRT2, EBTR2 = 11
005FFFh
006000h
WRT3, EBTR3 = 11
007FFFh
Results: Table reads permitted within Blockn, even when EBTRBn = 0.
TABLAT register returns the value of the data at the location TBLPTR.
DS41412C-page 364
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
24.3.2
DATA EEPROM
CODE PROTECTION
The entire data EEPROM is protected from external
reads and writes by two bits: CPD and WRTD. CPD
inhibits external reads and writes of data EEPROM.
WRTD inhibits internal and external writes to data
EEPROM. The CPU can always read data EEPROM
under normal operation, regardless of the protection bit
settings.
24.3.3
ID Locations
Eight memory locations (200000h-200007h) are
designated as ID locations, where the user can store
checksum or other code identification numbers. These
locations are both readable and writable during normal
execution through the TBLRD and TBLWT instructions
or during program/verify. The ID locations can be read
when the device is code-protected.
24.5
MCLR/VPP/RE3
VDD
VSS
RB7
RB6
24.7
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 24-6 shows which resources are
required by the background debugger.
TABLE 24-6:
I/O pins:
Single-Supply ICSP Programming
The LVP Configuration bit enables Single-Supply ICSP
Programming (formerly known as Low-Voltage ICSP
Programming or LVP). When Single-Supply Programming is enabled, the microcontroller can be programmed
without requiring high voltage being applied to the
MCLR/VPP/RE3 pin. See “PIC18(L)F2XK22/4XK22
Flash Memory Programming” (DS41398) for more
details about low voltage programming.
Note 1: High-voltage programming is always
available, regardless of the state of the
LVP bit, by applying VIHH to the MCLR
pin.
2: By default, Single-Supply ICSP is
enabled in unprogrammed devices (as
supplied from Microchip) and erased
devices.
In-Circuit Serial Programming
PIC18(L)F2X/4XK22 devices 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.
24.6
•
•
•
•
•
This will interface to the In-Circuit Debugger module
available from Microchip or one of the third party
development tool companies.
CONFIGURATION REGISTER
PROTECTION
The Configuration registers can be write-protected.
The WRTC bit controls protection of the Configuration
registers. In normal execution mode, the WRTC bit is
readable only. WRTC can only be written via ICSP or
an external programmer.
24.4
To use the In-Circuit Debugger function of the
microcontroller, the design must implement In-Circuit
Serial Programming connections to the following pins:
3: While in Low-Voltage ICSP mode, MCLR
is always enabled, regardless of the
MCLRE bit, and the RE3 pin can no
longer be used as a general purpose
input.
The LVP bit may be set or cleared only when using
standard high-voltage programming (VIHH applied to
the MCLR/VPP/RE3 pin). Once LVP has been disabled,
only the standard high-voltage programming is
available and must be used to program the device.
Memory that is not code-protected can be erased using
either a block erase, or erased row by row, then written
at any specified VDD. If code-protected memory is to be
erased, a block erase is required.
DEBUGGER RESOURCES
RB6, RB7
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 365
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 366
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
25.0
INSTRUCTION SET SUMMARY
PIC18(L)F2X/4XK22 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.
25.1
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 25-2 lists
byte-oriented, bit-oriented, literal and control
operations. Table 25-1 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.
• 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 s. If a conditional test is
true, or the program counter is changed as a result of
an instruction, the instruction execution time is 2 s.
Two-word branch instructions (if true) would take 3 s.
Figure 25-1 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 25-2,
lists the standard instructions recognized by the
Microchip Assembler (MPASMTM).
All bit-oriented instructions have three operands:
1.
2.
3.
The literal instructions may use some of the following
operands:
The file register (specified by ‘f’)
The bit in the file register (specified by ‘b’)
The accessed memory (specified by ‘a’)
Section 25.1.1 “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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 367
PIC18(L)F2X/4XK22
TABLE 25-1:
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).
DS41412C-page 368
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 25-1:
GENERAL FORMAT FOR INSTRUCTIONS
Byte-oriented file register operations
15
10
9 8 7
OPCODE d
a
Example Instruction
0
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
BSF MYREG, bit, B
f (FILE #)
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
OPCODE
0
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
CALL MYFUNC
n<7:0> (literal)
12 11
0
n<19:8> (literal)
1111
S = Fast bit
15
OPCODE
15
OPCODE
 2010 Microchip Technology Inc.
11 10
0
BRA MYFUNC
n<10:0> (literal)
8 7
0
n<7:0> (literal)
Preliminary
BC MYFUNC
DS41412C-page 369
PIC18(L)F2X/4XK22
TABLE 25-2:
PIC18(L)F2X/4XK22 INSTRUCTION SET
Mnemonic,
Operands
Description
Cycles
16-Bit Instruction Word
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 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:
DS41412C-page 370
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
Preliminary
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
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 25-2:
PIC18(L)F2X/4XK22 INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands
Description
Cycles
16-Bit Instruction Word
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 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:
 2010 Microchip Technology Inc.
1
1
2
Preliminary
TO, PD
C
None
None
None
None
None
None
All
GIE/GIEH,
PEIE/GIEL
kkkk None
001s None
0011 TO, PD
4
DS41412C-page 371
PIC18(L)F2X/4XK22
TABLE 25-2:
PIC18(L)F2X/4XK22 INSTRUCTION SET (CONTINUED)
Mnemonic,
Operands
Description
Cycles
16-Bit Instruction Word
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 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.
DS41412C-page 372
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
25.1.1
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.
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 25.2.3 “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).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 373
PIC18(L)F2X/4XK22
ADDWFC
ADD W and CARRY bit to f
ANDLW
Syntax:
ADDWFC
Syntax:
ANDLW
Operands:
0  f  255
d [0,1]
a [0,1]
Operands:
0  k  255
Operation:
(W) .AND. k  W
Status Affected:
N, Z
f {,d {,a}}
Operation:
(W) + (f) + (C)  dest
Status Affected:
N,OV, C, DC, Z
Encoding:
0010
Description:
00da
Encoding:
ffff
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
AND literal with W
0000
k
1011
kkkk
kkkk
Description:
The contents of W are AND’ed 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
=
DS41412C-page 374
REG, 0, 1
1
02h
4Dh
0
02h
50h
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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 AND’ed 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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
ANDWF
REG, 0, 0
Before Instruction
W
=
REG
=
After Instruction
W
REG
=
=
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
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
17h
C2h
02h
C2h
 2010 Microchip Technology Inc.
1110
If No Jump:
Q1
Example:
n
Preliminary
BC
5
=
address (HERE)
=
=
=
=
1;
address (HERE + 12)
0;
address (HERE + 2)
DS41412C-page 375
PIC18(L)F2X/4XK22
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q1
Q2
Q3
Q4
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
BCF
Before Instruction
FLAG_REG =
After Instruction
FLAG_REG =
DS41412C-page 376
FLAG_REG,
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:
Q Cycle Activity:
Decode
n
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
If No Jump:
7, 0
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
Preliminary
BN
Jump
=
address (HERE)
=
=
=
=
1;
address (Jump)
0;
address (HERE + 2)
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
BNC
Branch if Not Carry
BNN
Branch if Not Negative
Syntax:
BNC
Syntax:
BNN
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:
n
1110
Description:
0011
nnnn
nnnn
Encoding:
1110
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:
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
n
0111
nnnn
nnnn
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.
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)
 2010 Microchip Technology Inc.
Example:
HERE
Before Instruction
PC
After Instruction
If NEGATIVE
PC
If NEGATIVE
PC
Preliminary
BNN
Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
DS41412C-page 377
PIC18(L)F2X/4XK22
BNOV
Branch if Not Overflow
BNZ
Branch if Not Zero
Syntax:
BNOV
Syntax:
BNZ
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:
n
1110
Description:
0101
nnnn
nnnn
Encoding:
1110
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:
Words:
1
Words:
1
Cycles:
1(2)
Cycles:
1(2)
Q Cycle Activity:
If Jump:
n
0001
nnnn
nnnn
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.
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
=
DS41412C-page 378
BNOV Jump
Example:
HERE
Before Instruction
PC
After Instruction
If ZERO
PC
If ZERO
PC
address (HERE)
0;
address (Jump)
1;
address (HERE + 2)
Preliminary
BNZ
Jump
=
address (HERE)
=
=
=
=
0;
address (Jump)
1;
address (HERE + 2)
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
BRA
Unconditional Branch
BSF
Syntax:
BRA
Syntax:
BSF
Operands:
-1024  n  1023
Operands:
0  f  255
0b7
a [0,1]
n
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
Bit Set f
Operation:
1  f<b>
Status Affected:
None
Encoding:
1000
Q1
Q2
Q3
Q4
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
No
operation
No
operation
Example:
HERE
Before Instruction
PC
After Instruction
PC
BRA
Jump
=
address (HERE)
=
address (Jump)
ffff
ffff
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.
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 25.2.3 “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:
BSF
Before Instruction
FLAG_REG
After Instruction
FLAG_REG
 2010 Microchip Technology Inc.
bbba
Description:
Q Cycle Activity:
Decode
f, b {,a}
Preliminary
FLAG_REG, 7, 1
=
0Ah
=
8Ah
DS41412C-page 379
PIC18(L)F2X/4XK22
BTFSC
Bit Test File, Skip if Clear
BTFSS
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
bbba
ffff
ffff
Bit Test File, Skip if Set
Encoding:
1010
bbba
ffff
ffff
Description:
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Description:
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.
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 25.2.3 “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:
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
DS41412C-page 380
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
Preliminary
BTFSS
:
:
FLAG, 1, 0
=
address (HERE)
=
=
=
=
0;
address (FALSE)
1;
address (TRUE)
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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:
Words:
Cycles:
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
1110
Description:
0100
nnnn
nnnn
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:
1
Q1
Q2
Q3
Q4
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:
n
BTG
PORTC,
4, 0
Before Instruction:
PORTC =
0111 0101 [75h]
After Instruction:
PORTC =
0110 0101 [65h]
 2010 Microchip Technology Inc.
If No Jump:
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
Example:
HERE
Before Instruction
PC
=
After Instruction
If OVERFLOW =
PC
=
If OVERFLOW =
PC
=
Preliminary
BOV
Jump
address (HERE)
1;
address (Jump)
0;
address (HERE + 2)
DS41412C-page 381
PIC18(L)F2X/4XK22
BZ
Branch if Zero
CALL
Subroutine Call
Syntax:
BZ
Syntax:
CALL k {,s}
Operands:
-128  n  127
Operands:
Operation:
if ZERO bit is ‘1’
(PC) + 2 + 2n  PC
0  k  1048575
s [0,1]
Operation:
(PC) + 4  TOS,
k  PC<20:1>,
if s = 1
(W)  WS,
(Status)  STATUSS,
(BSR)  BSRS
Status Affected:
None
Status Affected:
n
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
Q1
Q2
Q3
Q4
Decode
Read literal
‘n’
Process
Data
No
operation
If No Jump:
Example:
HERE
Before Instruction
PC
After Instruction
If ZERO
PC
If ZERO
PC
DS41412C-page 382
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 =
Preliminary
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
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
CLRF
Clear f
Syntax:
CLRF
Operands:
0  f  255
a [0,1]
Operation:
000h  f
1Z
Status Affected:
Z
Encoding:
f {,a}
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
CLRWDT
Clear Watchdog Timer
Syntax:
CLRWDT
Operands:
None
Operation:
000h  WDT,
000h  WDT postscaler,
1  TO,
1  PD
Status Affected:
TO, PD
Encoding:
Q2
Q3
Q4
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
CLRF
Before Instruction
FLAG_REG
After Instruction
FLAG_REG
5Ah
=
00h
 2010 Microchip Technology Inc.
0100
Words:
1
Cycles:
1
Q Cycle Activity:
FLAG_REG, 1
=
0000
CLRWDT instruction resets the
Watchdog Timer. It also resets the
postscaler of the WDT. Status bits, TO
and PD, are set.
Q1
Q2
Q3
Q4
Decode
No
operation
Process
Data
No
operation
Example:
Q1
0000
Description:
Q Cycle Activity:
Decode
0000
Preliminary
CLRWDT
Before Instruction
WDT Counter
After Instruction
WDT Counter
WDT Postscaler
TO
PD
=
?
=
=
=
=
00h
0
1
1
DS41412C-page 383
PIC18(L)F2X/4XK22
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.
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 25.2.3 “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
Description:
f {,a}
001a
ffff
ffff
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.
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 25.2.3 “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
=
REG, 0, 0
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
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:
DS41412C-page 384
Preliminary
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)
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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:
Words:
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Encoding:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
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
=
=
Address (HERE)
?
If REG
PC
If REG
PC

=

=
W;
Address (GREATER)
W;
Address (NGREATER)
 2010 Microchip Technology Inc.
ffff
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:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
CPFSGT REG, 0
:
:
Before Instruction
PC
W
After Instruction
ffff
Words:
If skip:
Q4
No
operation
No
operation
000a
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.
Q Cycle Activity:
Q1
Decode
0110
Description:
1
Cycles:
f {,a}
Preliminary
HERE
NLESS
LESS
CPFSLT REG, 1
:
:
Before Instruction
PC
W
After Instruction
=
=
Address (HERE)
?
If REG
PC
If REG
PC
<
=

=
W;
Address (LESS)
W;
Address (NLESS)
DS41412C-page 385
PIC18(L)F2X/4XK22
DAW
Decimal Adjust W Register
DECF
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:
Decrement f
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
Cycles:
1
Q Cycle Activity:
DAW
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Before Instruction
=
=
=
A5h
0
0
ffff
1
Example1:
W
=
C
=
DC
=
After Instruction
ffff
Words:
0111
Description:
01da
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
C
Encoding:
W
C
DC
Example 2:
0000
Description:
Example:
DECF
Before Instruction
CNT
=
Z
=
After Instruction
CNT
=
Z
=
05h
1
0
CNT,
1, 0
01h
0
00h
1
Before Instruction
W
=
C
=
DC
=
After Instruction
W
C
DC
=
=
=
DS41412C-page 386
CEh
0
0
34h
1
0
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Decrement f, skip if 0
DCFSNZ
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
DECFSZ
Encoding:
0010
Description:
11da
ffff
ffff
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.
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 25.2.3 “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.
Decrement f, skip if not 0
Encoding:
0100
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
ffff
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.
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 25.2.3 “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.
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
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:
If skip and followed by 2-word instruction:
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
HERE
DECFSZ
GOTO
CNT, 1, 1
LOOP
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Example:
CONTINUE
HERE
ZERO
NZERO
Before Instruction
TEMP
After Instruction
TEMP
If TEMP
PC
If TEMP
PC
Address (HERE)
CNT - 1
0;
Address (CONTINUE)
0;
Address (HERE + 2)
 2010 Microchip Technology Inc.
ffff
Q Cycle Activity:
Q1
Before Instruction
PC
=
After Instruction
CNT
=
If CNT
=
PC =
If CNT

PC =
11da
Description:
Q Cycle Activity:
Example:
f {,d {,a}}
Preliminary
DCFSNZ
:
:
TEMP, 1, 0
=
?
=
=
=

=
TEMP – 1,
0;
Address (ZERO)
0;
Address (NZERO)
DS41412C-page 387
PIC18(L)F2X/4XK22
GOTO
Unconditional Branch
INCF
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
GOTO allows an unconditional branch
Description:
Increment f
Encoding:
0010
2
Cycles:
2
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
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
Decode
10da
Description:
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:
f {,d {,a}}
Q Cycle Activity:
Example:
GOTO THERE
After Instruction
PC =
Address (THERE)
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
=
DS41412C-page 388
Preliminary
CNT, 1, 0
FFh
0
?
?
00h
1
1
1
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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
Description:
11da
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 ‘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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Encoding:
0100
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:
10da
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.
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 25.2.3 “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
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
:
:
CNT, 1, 0
Example:
Before Instruction
PC
=
After Instruction
REG
=

If REG
PC
=
If REG
=
PC
=
Address (HERE)
CNT + 1
0;
Address (ZERO)
0;
Address (NZERO)
 2010 Microchip Technology Inc.
HERE
ZERO
NZERO
Preliminary
INFSNZ
REG, 1, 0
Address (HERE)
REG + 1
0;
Address (NZERO)
0;
Address (ZERO)
DS41412C-page 389
PIC18(L)F2X/4XK22
IORLW
Inclusive OR literal with W
IORWF
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
Description:
1001
kkkk
kkkk
The contents of W are ORed with the
eight-bit literal ‘k’. The result is placed in
W.
Words:
1
Cycles:
1
Inclusive OR W with f
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.
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 25.2.3 “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
=
DS41412C-page 390
Preliminary
RESULT, 0, 1
13h
91h
13h
93h
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
LFSR
Load FSR
MOVF
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
Move f
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.
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 25.2.3 “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
 2010 Microchip Technology Inc.
Preliminary
REG, 0, 0
=
=
22h
FFh
=
=
22h
22h
DS41412C-page 391
PIC18(L)F2X/4XK22
MOVFF
Move f to f
MOVLB
Syntax:
MOVFF fs,fd
Syntax:
MOVLW k
Operands:
0  fs  4095
0  fd  4095
Operands:
0  k  255
Operation:
k  BSR
Operation:
(fs)  fd
Status Affected:
None
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)
Move literal to low nibble in BSR
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
DS41412C-page 392
REG1, REG2
=
=
33h
11h
=
=
33h
33h
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
MOVLW
Move literal to W
MOVWF
Syntax:
MOVLW k
Syntax:
MOVWF
Operands:
0  k  255
Operands:
Operation:
kW
0  f  255
a  [0,1]
Status Affected:
None
Operation:
(W)  f
Status Affected:
None
Encoding:
0000
1110
kkkk
kkkk
Description:
The eight-bit literal ‘k’ is loaded into W.
Words:
1
Cycles:
1
Move W to f
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.
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 25.2.3 “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
 2010 Microchip Technology Inc.
Preliminary
=
=
4Fh
FFh
4Fh
4Fh
DS41412C-page 393
PIC18(L)F2X/4XK22
MULLW
Multiply literal with W
MULWF
Multiply W with f
Syntax:
MULLW
Syntax:
MULWF
Operands:
0  k  255
Operands:
Operation:
(W) x k  PRODH:PRODL
0  f  255
a  [0,1]
Status Affected:
None
Operation:
(W) x (f)  PRODH:PRODL
Status Affected:
None
Encoding:
0000
Description:
k
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.
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 25.2.3
“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
DS41412C-page 394
Preliminary
=
=
=
=
C4h
B5h
?
?
=
=
=
=
C4h
B5h
8Ah
94h
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
NEGF
Negate f
NOP
No Operation
Syntax:
NEGF
Syntax:
NOP
Operands:
0  f  255
a  [0,1]
Operands:
None
Operation:
(f)+1f
Status Affected:
N, OV, C, DC, Z
Encoding:
f {,a}
0110
Description:
1
Cycles:
1
No operation
Status Affected:
None
Encoding:
110a
ffff
0000
1111
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
Operation:
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]
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 395
PIC18(L)F2X/4XK22
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
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
DS41412C-page 396
0000
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.
Q Cycle Activity:
Example:
0000
Description:
Preliminary
PUSH
Before Instruction
TOS
PC
=
=
345Ah
0124h
After Instruction
PC
TOS
Stack (1 level down)
=
=
=
0126h
0126h
345Ah
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
RCALL
Relative Call
RESET
Reset
Syntax:
RCALL
Syntax:
RESET
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:
n
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
Q2
Q3
Q4
Read literal
‘n’
Process
Data
Write to PC
No
operation
No
operation
1111
This instruction provides a way to
execute a MCLR Reset by software.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Start
Reset
No
operation
No
operation
Example:
Q1
1111
Description:
Q Cycle Activity:
Decode
0000
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)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 397
PIC18(L)F2X/4XK22
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
DS41412C-page 398
kkkk
kkkk
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
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.
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
Description:
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
=
Preliminary
W contains table
offset value
W now has
table value
W = offset
Begin table
End of table
07h
value of kn
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
RETURN
Return from Subroutine
RLCF
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
Rotate Left f through Carry
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.
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 25.2.3
“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
=
 2010 Microchip Technology Inc.
Preliminary
RLCF
REG, 0, 0
1110 0110
0
1110 0110
1100 1100
1
DS41412C-page 399
PIC18(L)F2X/4XK22
RLNCF
Rotate Left f (No Carry)
RRCF
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Rotate Right f through Carry
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
=
DS41412C-page 400
00da
RLNCF
Words:
1
Cycles:
1
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.
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 25.2.3 “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
=
0101 0111
Preliminary
1110 0110
0
1110 0110
0111 0011
0
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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:
f {,d {,a}}
Encoding:
N, Z
Encoding:
0100
Description:
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 (default), overriding the BSR
value. If ‘a’ is ‘1’, then the bank will be
selected as per the BSR value.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
1
Cycles:
1
Q2
Q3
Q4
Read
register ‘f’
Process
Data
Write to
destination
Example 1:
RRNCF
Before Instruction
REG
=
After Instruction
REG
=
Example 2:
100a
ffff
ffff
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write
register ‘f’
Example:
Q1
0110
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.
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 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Q Cycle Activity:
Decode
f {,a}
Description:
register f
Words:
Set f
SETF
Before Instruction
REG
After Instruction
REG
REG, 1
=
5Ah
=
FFh
REG, 1, 0
1101 0111
1110 1011
RRNCF
REG, 0, 0
Before Instruction
W
=
REG
=
After Instruction
?
1101 0111
=
=
1110 1011
1101 0111
W
REG
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 401
PIC18(L)F2X/4XK22
SLEEP
Enter Sleep mode
SUBFWB
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
Decode
No
operation
Process
Data
Go to
Sleep
SLEEP
Before Instruction
TO =
?
PD =
?
DS41412C-page 402
01da
ffff
ffff
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.
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 25.2.3
“Byte-Oriented and Bit-Oriented
Instructions in Indexed Literal Offset
Mode” for details.
Words:
1
Cycles:
1
Q Cycle Activity:
After Instruction
1†
TO =
0
PD =
† If WDT causes wake-up, this bit is cleared.
f {,d {,a}}
Description:
Q Cycle Activity:
Example:
Subtract f from W with borrow
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
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
SUBLW
Subtract W from literal
SUBWF
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
Description
1000
kkkk
kkkk
W is subtracted from the eight-bit
literal ‘k’. The result is placed in W.
Words:
1
Cycles:
1
Subtract W from f
Encoding:
0101
Q2
Q3
Q4
Decode
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.
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 25.2.3
“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:
Q1
f {,d {,a}}
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
=
02h
03h
?
FFh ; (2’s complement)
0
; result is negative
0
1
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
=
 2010 Microchip Technology Inc.
Preliminary
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
DS41412C-page 403
PIC18(L)F2X/4XK22
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.
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 25.2.3 “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 1100)
(0000 1101)
10da
ffff
ffff
Description:
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.
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 25.2.3 “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
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:
=
=
=
=
DS41412C-page 404
; result is zero
REG, 1, 0
03h
0Eh
1
(0000 0011)
(0000 1110)
F5h
(1111 0101)
; [2’s comp]
(0000 1110)
0Eh
0
0
1
; result is negative
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TBLRD
Table Read
TBLRD
Table Read (Continued)
Syntax:
TBLRD ( *; *+; *-; +*)
Example1:
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;
Example2:
Status Affected: None
Encoding:
0000
0000
0000
*+ ;
Before Instruction
TABLAT
TBLPTR
MEMORY (00A356h)
After Instruction
TABLAT
TBLPTR
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
TBLRD
=
=
=
55h
00A356h
34h
=
=
34h
00A357h
+* ;
Before Instruction
TABLAT
TBLPTR
MEMORY (01A357h)
MEMORY (01A358h)
After Instruction
TABLAT
TBLPTR
=
=
=
=
AAh
01A357h
12h
34h
=
=
34h
01A358h
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)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 405
PIC18(L)F2X/4XK22
TBLWT
Table Write
TBLWT
Table Write (Continued)
Syntax:
TBLWT ( *; *+; *-; +*)
Example1:
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 6.0
“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
(Read
(Write to
TABLAT)
Holding
Register )
DS41412C-page 406
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TSTFSZ
Test f, skip if 0
XORLW
Syntax:
TSTFSZ f {,a}
Syntax:
XORLW k
Operands:
0  f  255
a  [0,1]
Operands:
0 k 255
Operation:
(W) .XOR. k W
Operation:
skip if f = 0
Status Affected:
N, Z
Status Affected:
None
Encoding:
Encoding:
0110
Description:
Exclusive OR literal with W
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.
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 25.2.3 “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)
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 407
PIC18(L)F2X/4XK22
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.
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 25.2.3 “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
=
DS41412C-page 408
REG, 1, 0
AFh
B5h
1Ah
B5h
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
25.2
Extended Instruction Set
A summary of the instructions in the extended instruction set is provided in Table 25-3. Detailed descriptions
are provided in Section 25.2.2 “Extended Instruction
Set”. The opcode field descriptions in Table 25-1 apply
to both the standard and extended PIC18 instruction
sets.
In addition to the standard 75 instructions of the PIC18
instruction set, PIC18(L)F2X/4XK22 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.
25.2.1
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 25.2.3.1 “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 25-3:
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
Mnemonic,
Operands
ADDFSR
ADDULNK
CALLW
MOVSF
f, k
k
MOVSS
zs, zd
PUSHL
k
SUBFSR
SUBULNK
f, k
k
zs, fd
Description
Cycles
Add literal to FSR
Add literal to FSR2 and return
Call subroutine using WREG
Move zs (source) to 1st word
fd (destination)
2nd word
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
 2010 Microchip Technology Inc.
1
2
2
2
16-Bit Instruction Word
MSb
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
Preliminary
None
None
DS41412C-page 409
PIC18(L)F2X/4XK22
25.2.2
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).
DS41412C-page 410
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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
 2010 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
Preliminary
Q4
Read
source reg
Write
register ‘f’
(dest)
[05h], REG2
=
80h
=
=
33h
11h
=
80h
=
=
33h
33h
DS41412C-page 411
PIC18(L)F2X/4XK22
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
Encoding:
Q1
Decode
Q2
Q3
Determine
Determine
source addr source addr
Determine
dest addr
Example:
1010
kkkk
kkkk
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
DS41412C-page 412
Determine
dest addr
1111
Description:
Q Cycle Activity:
Decode
Store Literal at FSR2, Decrement FSR2
=
80h
=
33h
=
11h
=
80h
=
33h
=
33h
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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:
 2010 Microchip Technology Inc.
Preliminary
SUBULNK 23h
Before Instruction
FSR2
=
PC
=
03FFh
0100h
After Instruction
FSR2
=
PC
=
03DCh
(TOS)
DS41412C-page 413
PIC18(L)F2X/4XK22
25.2.3
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 5.5.1
“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 25.2.3.1
“Extended Instruction Syntax with Standard PIC18
Commands”).
25.2.3.1
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.
In the latest versions of the MPASM™ assembler,
language support for the extended instruction set must
be explicitly invoked. This is done with either the
command line option, /y, or the PE directive in the
source listing.
25.2.4
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.
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.
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.
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.
When porting an application to the PIC18(L)F2X/
4XK22, 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.
DS41412C-page 414
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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
Example:
Before Instruction
FLAG_OFST
FSR2
Contents
of 0A0Ah
After Instruction
Contents
of 0A0Ah
[OFST] , 0
Before Instruction
W
OFST
FSR2
Contents
of 0A2Ch
After Instruction
W
Contents
of 0A2Ch
=
=
=
17h
2Ch
0A00h
=
20h
=
37h
=
20h
BSF
[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
 2010 Microchip Technology Inc.
Preliminary
[OFST]
=
=
2Ch
0A00h
=
00h
=
FFh
DS41412C-page 415
PIC18(L)F2X/4XK22
25.2.5
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 PIC18(L)F2X/4XK22 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.
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.
DS41412C-page 416
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
26.0
DEVELOPMENT SUPPORT
26.1
The PIC® microcontrollers and dsPIC® digital signal
controllers are supported with a full range of software
and hardware development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Compilers/Assemblers/Linkers
- MPLAB C Compiler for Various Device
Families
- HI-TECH C for Various Device Families
- MPASMTM Assembler
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
- MPLAB Assembler/Linker/Librarian for
Various Device Families
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB REAL ICE™ In-Circuit Emulator
• In-Circuit Debuggers
- MPLAB ICD 3
- PICkit™ 3 Debug Express
• Device Programmers
- PICkit™ 2 Programmer
- MPLAB PM3 Device Programmer
• Low-Cost Demonstration/Development Boards,
Evaluation Kits, and Starter Kits
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8/16/32-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)
- In-Circuit 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
• 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
IAR C Compilers
The MPLAB IDE allows you to:
• Edit your source files (either C or assembly)
• One-touch compile or assemble, and download to
emulator and simulator tools (automatically
updates all project information)
• Debug using:
- Source files (C or assembly)
- Mixed C and assembly
- 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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 417
PIC18(L)F2X/4XK22
26.2
MPLAB C Compilers for Various
Device Families
The MPLAB C Compiler code development systems
are complete ANSI C compilers for Microchip’s PIC18,
PIC24 and PIC32 families of microcontrollers and the
dsPIC30 and dsPIC33 families of digital signal controllers. These compilers provide powerful integration
capabilities, superior code optimization and ease of
use.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
26.3
HI-TECH C for Various Device
Families
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
The compilers include a macro assembler, linker, preprocessor, and one-step driver, and can run on multiple
platforms.
MPASM Assembler
The MPASM Assembler is a full-featured, universal
macro assembler for PIC10/12/16/18 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:
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.
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:
The HI-TECH C Compiler code development systems
are complete ANSI C compilers for Microchip’s PIC
family of microcontrollers and the dsPIC family of digital
signal controllers. These compilers provide powerful
integration capabilities, omniscient code generation
and ease of use.
26.4
26.5
• 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
26.6
MPLAB Assembler, Linker and
Librarian for Various Device
Families
MPLAB Assembler produces relocatable machine
code from symbolic assembly language for PIC24,
PIC32 and dsPIC devices. MPLAB 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 device instruction set
Support for fixed-point and floating-point data
Command line interface
Rich directive set
Flexible macro language
MPLAB IDE compatibility
• 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
DS41412C-page 418
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
26.7
MPLAB SIM Software Simulator
26.9
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 C Compilers,
and the MPASM and MPLAB 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.
26.8
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 emulator 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 incircuit debugger systems (RJ11) or with the new highspeed, noise tolerant, Low-Voltage Differential Signal
(LVDS) interconnection (CAT5).
The emulator is field upgradable through future firmware
downloads in MPLAB IDE. In upcoming releases of
MPLAB IDE, new devices will be supported, and new
features will be added. MPLAB REAL ICE offers significant advantages over competitive emulators including
low-cost, full-speed emulation, run-time variable
watches, trace analysis, complex breakpoints, a ruggedized probe interface and long (up to three meters) interconnection cables.
 2010 Microchip Technology Inc.
MPLAB ICD 3 In-Circuit Debugger
System
MPLAB ICD 3 In-Circuit Debugger System is Microchip's most cost effective high-speed hardware
debugger/programmer for Microchip Flash Digital Signal Controller (DSC) and microcontroller (MCU)
devices. It debugs and programs PIC® Flash microcontrollers and dsPIC® DSCs with the powerful, yet easyto-use graphical user interface of MPLAB Integrated
Development Environment (IDE).
The MPLAB ICD 3 In-Circuit Debugger probe is connected to the design engineer's PC using a high-speed
USB 2.0 interface and is connected to the target with a
connector compatible with the MPLAB ICD 2 or MPLAB
REAL ICE systems (RJ-11). MPLAB ICD 3 supports all
MPLAB ICD 2 headers.
26.10 PICkit 3 In-Circuit Debugger/
Programmer and
PICkit 3 Debug Express
The MPLAB PICkit 3 allows debugging and programming of PIC® and dsPIC® Flash microcontrollers at a
most affordable price point using the powerful graphical
user interface of the MPLAB Integrated Development
Environment (IDE). The MPLAB PICkit 3 is connected
to the design engineer's PC using a full speed USB
interface and can be connected to the target via an
Microchip debug (RJ-11) connector (compatible with
MPLAB ICD 3 and MPLAB REAL ICE). The connector
uses two device I/O pins and the reset line to implement in-circuit debugging and In-Circuit Serial Programming™.
The PICkit 3 Debug Express include the PICkit 3, demo
board and microcontroller, hookup cables and CDROM
with user’s guide, lessons, tutorial, compiler and
MPLAB IDE software.
Preliminary
DS41412C-page 419
PIC18(L)F2X/4XK22
26.11 PICkit 2 Development
Programmer/Debugger and
PICkit 2 Debug Express
26.13 Demonstration/Development
Boards, Evaluation Kits, and
Starter Kits
The PICkit™ 2 Development Programmer/Debugger is
a low-cost development tool with an easy to use interface for programming and debugging Microchip’s Flash
families of microcontrollers. The full featured
Windows® programming interface supports baseline
(PIC10F,
PIC12F5xx,
PIC16F5xx),
midrange
(PIC12F6xx, PIC16F), PIC18F, PIC24, dsPIC30,
dsPIC33, and PIC32 families of 8-bit, 16-bit, and 32-bit
microcontrollers, and many Microchip Serial EEPROM
products. With Microchip’s powerful MPLAB Integrated
Development Environment (IDE) the PICkit™ 2
enables in-circuit debugging on most PIC® microcontrollers. In-Circuit-Debugging runs, halts and single
steps the program while the PIC microcontroller is
embedded in the application. When halted at a breakpoint, the file registers can be examined and modified.
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.
The PICkit 2 Debug Express include the PICkit 2, demo
board and microcontroller, hookup cables and CDROM
with user’s guide, lessons, tutorial, compiler and
MPLAB IDE software.
26.12 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 MMC card for file
storage and data applications.
DS41412C-page 420
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.
Also available are starter kits that contain everything
needed to experience the specified device. This usually
includes a single application and debug capability, all
on one board.
Check the Microchip web page (www.microchip.com)
for the complete list of demonstration, development
and evaluation kits.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings (†)
Ambient temperature under bias.............................................................................................................-40°C to +125°C
Storage temperature .............................................................................................................................. -65°C to +150°C
Voltage on any pin with respect to VSS (except VDD, and MCLR) .................................................. -0.3V to (VDD + 0.3V)
Voltage on VDD with respect to VSS
PIC18LF46K22 ......................................................................................................... -0.3V to +4.5V
PIC18F46K22 ........................................................................................................... -0.3V to +6.5V
Voltage on MCLR with respect to VSS (Note 2) ............................................................................................0V to +11.0V
Total power dissipation (Note 1) ...............................................................................................................................1.0W
Maximum current out of VSS pin (-40°C to +85°C) .............................................................................................. 300 mA
Maximum current out of VSS pin (+85°C to +125°C)............................................................................................ 125 mA
Maximum current into VDD pin (-40°C to +85°C) ................................................................................................ 200 mA
Maximum current into VDD pin (+85°C to +125°C) ................................................................................................85 mA
Input clamp current, IIK (VI < 0 or VI > VDD) 20 mA
Output clamp current, IOK (VO < 0 or VO > VDD)  20 mA
Maximum output current sunk by any I/O pin..........................................................................................................25 mA
Maximum output current sourced by any I/O pin ....................................................................................................25 mA
Maximum current sunk byall ports (-40°C to +85°C)........................................................................................... 200 mA
Maximum current sunk byall ports (+85°C to +125°C)......................................................................................... 110 mA
Maximum current sourced by all ports (-40°C to +85°C) ......................................................................................185 mA
Maximum current sourced by all ports (+85°C to +125°C) .....................................................................................70 mA
Note 1: Power dissipation is calculated as follows:
Pdis = VDD x {IDD –  IOH} +  {(VDD – VOH) x IOH} + (VOL x IOL)
2: Voltage spikes below VSS at the MCLR/VPP/RE3 pin, inducing currents greater than 80 mA, may cause
latch-up. Thus, a series resistor of 50-100 should be used when applying a “low” level to the MCLR/VPP/
RE3 pin, rather than pulling this pin directly to VSS.
† 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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 421
PIC18(L)F2X/4XK22
FIGURE 27-1:
PIC18(L)F46K22 FAMILY VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL
TEMPERATURE)
5.5V
3.6V
3.5V
3.0V
Voltage
2.7V
2.2V
1.8V
10
20
30 32
40
50
60
64
Frequency (MHz)
Note 1: Maximum Frequency 20 MHz, 1.8V to 3.0V, -40°C to +85°C (PIC18(L)F2X/4XK22).
2: Maximum Frequency 64 MHz, 3.0V to 3.6V, -40°C to +85°C (PIC18LF2X/4XK22).
3: Maximum Frequency 64 MHz, 3.0V to 5.5V, -40°C to +85°C (PIC18F2X/4XK22).
FIGURE 27-2:
PIC18(L)F46K22 FAMILY VOLTAGE-FREQUENCY GRAPH (EXTENDED
TEMPERATURE)
5.5V
3.6V
3.5V
3.0V
Voltage
2.7V
2.2V
1.8V
10
16
20
30 32
40
48
Frequency (MHz)
Note 1: Maximum Frequency 16 MHz, 1.8V to 2.7V, -40°C to +125°C (PIC18(L)F2X/4XK22).
2: Maximum Frequency 48 MHz, 2.7V to 3.6V, -40°C to +125°C (PIC18LF2X/4XK22).
3: Maximum Frequency 48 MHz, 2.7V to 5.5V, -40°C to +125°C (PIC18F2X/4XK22).
DS41412C-page 422
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.1
DC Characteristics: Supply Voltage, PIC18(L)F2X/4XK22
Standard Operating Conditions (unless otherwise
stated)
Operating temperature
-40°C  TA  +125°C
PIC18(L)F2X/4XK22
Param
Symbol
No.
Characteristic
Min
D001
VDD
Supply Voltage
D002
VDR
RAM Data Retention Voltage(1)
D003
VPOR
VDD Start Voltage to ensure internal
Power-on Reset signal
D004
SVDD
VDD Rise Rate to ensure internal
Power-on Reset signal
D005
VBOR
Brown-out Reset Voltage
Note 1:
2:
3:
Typ Max Units
PIC18LF2X/4XK22
1.8
—
3.6
V
PIC18F2X/4XK22
1.8
—
5.5
V
1.5
—
—
V
—
—
0.7
V
0.05
—
—
BORV<1:0> = 11(2)
—
1.9
—
V
BORV<1:0> = 10
—
2.2
—
V
BORV<1:0> = 01
—
2.5
—
V
BORV<1:0> = 00(3)
—
2.85
—
V
Conditions
See section on Power-on Reset
for details
V/ms See section on Power-on Reset
for details
This is the limit to which VDD can be lowered in Sleep mode, or during a device Reset, without losing RAM
data.
With BOR enabled, operation is supported until a BOR occurs. This is valid although VDD may be below
the minimum rated supply voltage.
With BOR enabled, full-speed operation (FOSC = 64 MHz) is supported until a BOR occurs. This is valid
although VDD may be below the minimum voltage for this frequency.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 423
PIC18(L)F2X/4XK22
27.2
DC Characteristics: Power-Down Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Typ
Typ
Max
Max
+25°C +60°C +85°C +125°C
Device Characteristics
Power-down Base Current (IPD)
D006
Units
Conditions
VDD
Notes
WDT, BOR, FVR and
SOSC disabled, all Peripherals inactive
(1)
Sleep mode
0.02
2
10
A
1.8V
0.02
2
10
A
3.0V
10
25
35
A
1.8V
11
25
35
A
3.0V
12
25
35
A
5.0V
0.3
2.5
2.5
A
1.8V
0.5
2.5
2.5
A
3.0V
0.3
2.5
2.5
A
1.8V
0.5
2.5
2.5
A
3.0V
0.5
2.5
2.5
A
5.0V
10
20
20
A
2.0V
12
20
20
A
3.0V
25
40
40
A
2.0V
30
50
50
A
3.0V
65
90
90
A
5.0V
0.0
0.0
0.0
A
1.8V3.6V
0.0
0.0
0.0
A
1.8V5.5V
TBD
TBD
TBD
A
2.0V
TBD
TBD
TBD
A
3.0V
TBD
TBD
TBD
A
2.0V
TBD
TBD
TBD
A
3.0V
TBD
TBD
TBD
A
5.0V
Power-down Module Differential Current (delta IPD)
D007
Watchdog Timer
D008
Brown-out Reset
D009
Brown-out Reset
(2)
(2)
High/Low Voltage Detect (2)
D010
Note 1:
2:
3:
Sleep mode,
BOREN<1:0> = 10
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, BOR, etc.).
BOR, HLVD and FVR enable internal band gap reference. With both modules enabled, current consumption will be less than the sum of both specifications.
A/D converter differential currents apply only in Run mode. In Sleep or Idle mode both the ADC and the
FRC turn off as soon as conversion (if any) is complete.
DS41412C-page 424
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.2
DC Characteristics: Power-Down Current, PIC18(L)F2X/4XK22 (Continued)
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Typ
Typ
Max
Max
+25°C +60°C +85°C +125°C
D011
Device Characteristics
Secondary Oscillator
A/D Converter (3)
D013
D014
A/D Converter
D015
D16
Comparators
Note 1:
2:
3:
Conditions
VDD
0.8
3
3
A
1.8V
0.9
4
4
A
3.0V
0.8
3
3
A
1.8V
0.9
4
4
A
3.0V
1
5
5
A
5.0V
200
A
1.8V
260
A
3.0V
200
A
1.8V
260
A
3.0V
260
A
5.0V
A
1.8V
A
3.0V
A
1.8V
A
3.0V
A
5.0V
(3)
Comparators
Units
9
15
15
A
1.8V
9
15
15
A
3.0V
9
15
15
A
1.8V
9
15
15
A
3.0V
9
15
15
A
5.0V
50
80
80
A
1.8V
50
80
80
A
3.0V
50
80
80
A
1.8V
50
80
80
A
3.0V
50
80
80
A
5.0V
Notes
32 kHz on SOSC
A/D on, not converting
Adder to A/D current for
FRC conversion clock.
LP mode
HP 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, BOR, etc.).
BOR, HLVD and FVR enable internal band gap reference. With both modules enabled, current consumption will be less than the sum of both specifications.
A/D converter differential currents apply only in Run mode. In Sleep or Idle mode both the ADC and the
FRC turn off as soon as conversion (if any) is complete.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 425
PIC18(L)F2X/4XK22
27.2
DC Characteristics: Power-Down Current, PIC18(L)F2X/4XK22 (Continued)
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Typ
Typ
Max
Max
+25°C +60°C +85°C +125°C
D017
Device Characteristics
DAC
D018
FVR
Note 1:
2:
3:
Units
Conditions
VDD
Notes
12
20
20
A
1.8V
20
30
30
A
3.0V
12
20
20
A
1.8V
20
30
30
A
3.0V
33
50
50
A
5.0V
15
25
25
A
1.8V
15
25
25
A
3.0V
30
45
45
A
1.8V
35
55
55
A
3.0V
70
100
100
A
5.0V
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, BOR, etc.).
BOR, HLVD and FVR enable internal band gap reference. With both modules enabled, current consumption will be less than the sum of both specifications.
A/D converter differential currents apply only in Run mode. In Sleep or Idle mode both the ADC and the
FRC turn off as soon as conversion (if any) is complete.
DS41412C-page 426
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.3
DC Characteristics: RC Run Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
Supply Current (IDD)(1),(2)
D020
D021
D022
D023
D024
Typ
Max
Units
Conditions
5.0
14
A
-40°C
4.0
14
A
+25°C
4.0
—
A
+60°C
4.5
18
A
+85°C
7.0
30
A
125°C
8.0
20
A
-40°C
7.0
20
A
+25°C
7.0
—
A
+60°C
7.5
22
A
+85°C
10.0
35
A
+125°C
12
50
A
-40°C
15
50
A
+25°C
17
50
A
+85°C
20
60
A
+125°C
16
50
A
-40°C
19
50
A
+25°C
23
50
A
+85°C
25
60
A
+125°C
17
50
A
-40°C
21
50
A
+25°C
24
50
A
+85°C
VDD = 1.8V
FOSC = 31 kHz
(RC_RUN mode,
LFINTOSC source)
VDD = 3.0V
VDD = 1.8V
VDD = 3.0V
VDD = 5.0V
28
60
A
+125°C
D025
0.12
0.25
mA
-40°C to +125°C
VDD = 1.8V
D026
0.15
0.30
mA
-40°C to +125°C
VDD = 3.0V
D027
0.16
0.30
mA
-40°C to +125°C
VDD = 1.8V
D028
0.20
0.40
mA
-40°C to +125°C
VDD = 3.0V
D029
0.25
0.50
mA
-40°C to +125°C
VDD = 5.0V
D030
0.30
0.50
mA
-40°C to +125°C
VDD = 1.8V
D031
0.40
0.70
mA
-40°C to +125°C
VDD = 3.0V
D032
0.35
0.60
mA
-40°C to +125°C
VDD = 1.8V
D033
0.45
0.80
mA
-40°C to +125°C
VDD = 3.0V
D034
0.55
0.90
mA
-40°C to +125°C
VDD = 5.0V
Note 1:
2:
FOSC = 31 kHz
(RC_RUN mode,
LFINTOSC source)
FOSC = 500 KHz
(RC_RUN mode,
MFINTOSC source)
FOSC = 500 KHz
(RC_RUN mode,
MFINTOSC source)
FOSC = 1 MHz
(RC_RUN mode,
HFINTOSC source)
FOSC = 1 MHz
(RC_RUN mode,
HFINTOSC source)
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.
Test condition: All Peripheral Module Control bits in PMD0, PMD1 and PMD2 set to ‘1’.
The test conditions for all IDD measurements in active operation mode are:
All I/O pins set as outputs driven to Vss;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI_IDLE only).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 427
PIC18(L)F2X/4XK22
27.3
DC Characteristics: RC Run Supply Current, PIC18(L)F2X/4XK22 (Continued)
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
D035
Typ
Max
Units
1.0
1.7
mA
-40°C to +125°C
VDD = 1.8V
2.8
mA
-40°C to +125°C
VDD = 3.0V
1.7
D036
Conditions
D037
1.2
1.9
mA
-40°C to +125°C
VDD = 1.8V
D038
2.0
3.2
mA
-40°C to +125°C
VDD = 3.0V
D039
2.3
3.6
mA
-40°C to +125°C
VDD = 5.0V
D041
6.5
10
mA
-40°C to +125°C
VDD = 3.0V
D043
7.0
11.0
mA
-40°C to +125°C
VDD = 3.0V
12.0
mA
-40°C to +125°C
VDD = 5.0V
7.9
D044
Note 1:
2:
FOSC = 16 MHz
(RC_RUN mode,
HFINTOSC source)
FOSC = 16 MHz
(RC_RUN mode,
HFINTOSC source)
FOSC = 64 MHz
(RC_RUN mode,
HFINTOSC + PLL
source)
FOSC = 64 MHz
(RC_RUN mode,
HFINTOSC + PLL
source)
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.
Test condition: All Peripheral Module Control bits in PMD0, PMD1 and PMD2 set to ‘1’.
The test conditions for all IDD measurements in active operation mode are:
All I/O pins set as outputs driven to Vss;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI_IDLE only).
DS41412C-page 428
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.4
DC Characteristics: RC Idle Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
Typ
Supply Current (IDD)(1),(2)
2.5
Max Units
Conditions
8
A
-40°C
1.5
8
A
+25°C
1.5
—
A
+60°C
2.0
10
A
+85°C
4.0
25
A
+125°C
3.0
10
A
-40°C
2.0
10
A
+25°C
2.0
—
A
+60°C
2.5
12
A
+85°C
5.0
30
A
+125°C
10
50
A
-40°C
13
50
A
+25°C
15
50
A
+85°C
18
60
A
+125°C
12
50
A
-40°C
14
50
A
+25°C
17
50
A
+85°C
20
60
A
+125°C
13
50
A
-40°C
16
50
A
+25°C
18
50
A
+85°C
23
60
A
+125°C
D050
0.10
0.20
mA
-40°C to +125°C
VDD = 1.8V
D051
0.12
0.25
mA
-40°C to +125°C
VDD = 3.0V
D052
0.13
0.25
mA
-40°C to +125°C
VDD = 1.8V
D053
0.15
0.30
mA
-40°C to +125°C
VDD = 3.0V
D054
0.20
0.40
mA
-40°C to +125°C
VDD = 5.0V
D055
0.25
0.40
mA
-40°C to +125°C
VDD = 1.8V
D056
0.35
0.60
mA
-40°C to +125°C
VDD = 3.0V
D045
D046
D047
D048
D049
Note 1:
2:
VDD = 1.8V
FOSC = 31 kHz
(RC_IDLE mode,
LFINTOSC source)
VDD = 3.0V
VDD = 1.8V
VDD = 3.0V
FOSC = 31 kHz
(RC_IDLE mode,
LFINTOSC source)
VDD = 5.0V
FOSC = 500 KHz
(RC_IDLE mode,
MFINTOSC source)
FOSC = 500 KHz
(RC_IDLE mode,
MFINTOSC source)
FOSC = 1 MHz
(RC_IDLE mode,
HFINTOSC source)
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.
For RC oscillator configurations, current through REXT is not included. The current through the resistor can
be estimated by the formula Ir = VDD/2REXT (mA) with REXT in k.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 429
PIC18(L)F2X/4XK22
27.4
DC Characteristics: RC Idle Supply Current, PIC18(L)F2X/4XK22 (Continued)
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
Typ
Max Units
0.3
0.50
mA
-40°C to +125°C
VDD = 1.8V
D058
0.4
0.70
mA
-40°C to +125°C
VDD = 3.0V
D059
0.45
0.80
mA
-40°C to +125°C
VDD = 5.0V
D060
0.5
0.9
mA
-40°C to +125°C
VDD = 1.8V
D061
0.8
1.4
mA
-40°C to +125°C
VDD = 3.0V
D062
0.6
1.0
mA
-40°C to +125°C
VDD = 1.8V
D063
0.9
1.4
mA
-40°C to +125°C
VDD = 3.0V
D064
1.1
1.7
mA
-40°C to +125°C
VDD = 5.0V
D066
2.5
4
mA
-40°C to +125°C
VDD = 3.0V
D068
3.0
5.0
mA
-40°C to +125°C
VDD = 3.0V
D069
3.5
6.0
mA
-40°C to +125°C
VDD = 5.0V
D057
Note 1:
2:
Conditions
FOSC = 1 MHz
(RC_IDLE mode,
HFINTOSC source)
FOSC = 16 MHz
(RC_IDLE mode,
HFINTOSC source)
FOSC = 16 MHz
(RC_IDLE mode,
HFINTOSC source)
FOSC = 64 MHz
(RC_IDLE mode,
HFINTOSC + PLL
source)
FOSC = 64 MHz
(RC_IDLE mode,
HFINTOSC + PLL
source)
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.
For RC oscillator configurations, current through REXT is not included. The current through the resistor can
be estimated by the formula Ir = VDD/2REXT (mA) with REXT in k.
DS41412C-page 430
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.5
DC Characteristics: Primary Run Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
Typ
Max Units
Supply Current (IDD)(1),(2)
0.07
0.14
mA
-40°C to +125°C
VDD = 1.8V
0.12
0.25
mA
-40°C to +125°C
VDD = 3.0V
D072
0.08
0.20
mA
-40°C to +125°C
VDD = 1.8V
D073
0.13
0.25
mA
-40°C to +125°C
VDD = 3.0V
D074
0.15
0.30
mA
-40°C to +125°C
VDD = 5.0V
D075
1.2
2.0
mA
-40°C to +125°C
VDD = 1.8V
D076
2.2
3.8
mA
-40°C to +125°C
VDD = 3.0V
D077
1.4
2.5
mA
-40°C to +125°C
VDD = 1.8V
D078
2.4
4.0
mA
-40°C to +125°C
VDD = 3.0V
D079
2.7
4.5
mA
-40°C to +125°C
VDD = 5.0V
6.5
11
mA
-40°C to +125°C
VDD = 3.0V
D081
6.8
11
mA
-40°C to +125°C
VDD = 3.0V
D082
7.5
13
mA
-40°C to +125°C
VDD = 5.0V
D083
1.0
1.7
mA
-40°C to +125°C
VDD = 1.8V
1.8
3.2
mA
-40°C to +125°C
VDD = 3.0V
D085
1.0
1.8
mA
-40°C to +125°C
VDD = 1.8V
D086
1.9
3.5
mA
-40°C to +125°C
VDD = 3.0V
D087
2.2
4.0
mA
-40°C to +125°C
VDD = 5.0V
D070
D071
Conditions
D080
D084
D088
6.5
Note 1:
2:
10
mA
-40°C to +125°C
VDD = 3.0V
FOSC = 1 MHz
(PRI_RUN,
EC oscillator)
FOSC = 1 MHz
(PRI_RUN,
EC oscillator)
FOSC = 20 MHz
(PRI_RUN,
EC oscillator)
FOSC = 20 MHz
(PRI_RUN,
EC oscillator)
FOSC = 64 MHz
(PRI_RUN,
EC oscillator)
FOSC = 64 MHz
(PRI_RUN,
EC oscillator)
FOSC = 4 MHz
16 MHz Internal
(PRI_RUN, EC +
PLL)
FOSC = 4 MHz
16 MHz Internal
(PRI_RUN, EC +
PLL)
FOSC = 16 MHz
64 MHz Internal
(PRI_RUN, EC +
PLL)
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.
The test conditions for all IDD measurements in active operation mode are:
All I/O pins set as outputs driven to VSS;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI-IDLE only).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 431
PIC18(L)F2X/4XK22
27.5
DC Characteristics: Primary Run Supply Current, PIC18(L)F2X/4XK22 (Continued)
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
D089
D090
Note 1:
2:
Typ
Max Units
Conditions
6.8
11
mA
-40°C to +125°C
VDD = 3.0V
7.5
13
mA
-40°C to +125°C
VDD = 5.0V
FOSC = 16 MHz
64 MHz Internal
(PRI_RUN, EC +
PLL)
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.
The test conditions for all IDD measurements in active operation mode are:
All I/O pins set as outputs driven to VSS;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI-IDLE only).
DS41412C-page 432
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.6
DC Characteristics: Primary Idle Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
Supply Current (IDD)(1),(2)
D100
Typ
Max Units
Conditions
0.025 0.07
mA
-40°C to +125°C
VDD = 1.8V
D101
0.045 0.10
mA
-40°C to +125°C
VDD = 3.0V
D102
0.04
0.12
mA
-40°C to +125°C
VDD = 1.8V
D103
0.06
0.15
mA
-40°C to +125°C
VDD = 3.0V
D104
0.07
0.17
mA
-40°C to +125°C
VDD = 5.0V
D105
0.45
0.65
mA
-40°C to +125°C
VDD = 1.8V
D106
0.75
1.10
mA
-40°C to +125°C
VDD = 3.0V
D107
0.5
0.8
mA
-40°C to +125°C
VDD = 1.8V
D108
0.9
1.5
mA
-40°C to +125°C
VDD = 3.0V
D109
1.1
1.8
mA
-40°C to +125°C
VDD = 5.0V
2.5
4
mA
-40°C to +125°C
VDD = 3.0V
2.7
4.2
mA
-40°C to +125°C
VDD = 3.0V
3.3
5.0
mA
-40°C to +125°C
VDD = 5.0V
0.40
0.70
mA
-40°C to +125°C
VDD = 1.8V
0.65
1.10
mA
-40°C to +125°C
VDD = 3.0V
0.4
0.7
mA
-40°C to +125°C
VDD = 1.8V
0.7
1.2
mA
-40°C to +125°C
VDD = 3.0V
0.9
1.5
mA
-40°C to +125°C
VDD = 5.0V
D110
D111
D112
D113
D114
D115
D116
D117
D118
D119
D120
Note 1:
2:
2.5
4
mA
-40°C to +125°C
VDD = 3.0V
2.7
5.0
mA
-40°C to +125°C
VDD = 3.0V
3.3
6.0
mA
-40°C to +125°C
VDD = 5.0V
FOSC = 1 MHz
(PRI_IDLE mode,
EC oscillator)
FOSC = 1 MHz
(PRI_IDLE mode,
EC oscillator)
FOSC = 20 MHz
(PRI_IDLEmode,
EC oscillator)
FOSC = 20 MHz
(PRI_IDLEmode,
EC oscillator)
FOSC = 64 MHz
(PRI_IDLEmode,
EC oscillator)
FOSC = 64 MHz
(PRI_IDLEmode,
EC oscillator)
FOSC = 4 MHz
16 MHz Internal
(PRI_IDLE, EC +
PLL)
FOSC = 4 MHz
16 MHz Internal
(PRI_IDLE, EC +
PLL)
FOSC = 16 MHz
64 MHz Internal
(PRI_IDLE, EC +
PLL)
FOSC = 16 MHz
64 MHz Internal
(PRI_IDLE, EC +
PLL)
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:
All I/O pins set as outputs driven to VSS;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI-IDLE only).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 433
PIC18(L)F2X/4XK22
27.7
DC Characteristics: Secondary Oscillator Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
D130
Device Characteristics
Typ
Supply Current (IDD)(1),(2)
4.0
14
A
-40°C
4.5
14
A
+25°C
5.0
—
A
+60°C
5.5
18
A
+85°C
9.0
30
A
+125°C
7.0
20
A
-40°C
7.5
20
A
+25°C
8.0
—
A
+60°C
8.5
22
A
+85°C
11.0
35
A
+125°C
12
50
A
-40°C
16
50
A
+25°C
19
50
A
+85°C
22
60
A
+125°C
16
50
A
-40°C
20
50
A
+25°C
23
50
A
+85°C
27
60
A
+125°C
18
50
A
-40°C
22
50
A
+25°C
25
50
A
+85°C
30
60
A
+125°C
1.5
8
A
-40°C
2.0
8
A
+25°C
2.5
—
A
+60°C
3.0
10
A
+85°C
6.0
25
A
+125°C
2.0
10
A
-40°C
2.5
10
A
+25°C
3.0
—
A
+60°C
3.5
12
A
+85°C
7.0
30
A
+125°C
D131
D132
D133
D134
D135
D136
Note 1:
2:
Max Units
Conditions
VDD = 1.8V
FOSC = 32 kHz
(SEC_RUN mode,
SOSC source)
VDD = 3.0V
VDD = 1.8V
VDD = 3.0V
FOSC = 32 kHz
(SEC_RUN mode,
SOSC source)
VDD = 5.0V
VDD = 1.8V
FOSC = 32 kHz
(SEC_IDLE mode,
SOSC source)
VDD = 3.0V
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:
All I/O pins set as outputs driven to VSS;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI_IDLE only).
DS41412C-page 434
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.7
DC Characteristics: Secondary Oscillator Supply Current, PIC18(L)F2X/4XK22
PIC18LF2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
PIC18F2X/4XK22
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Param
No.
Device Characteristics
D137
D138
D139
Note 1:
2:
Typ
Max Units
Conditions
10
50
A
-40°C
13
50
A
+25°C
16
50
A
+85°C
19
60
A
+125°C
11
50
A
-40°C
15
50
A
+25°C
18
50
A
+85°C
22
60
A
+125°C
13
50
A
-40°C
17
50
A
+25°C
20
50
A
+85°C
24
60
A
+125°C
VDD = 1.8V
VDD = 3.0V
FOSC = 32 kHz
(SEC_IDLE mode,
SOSC source)
VDD = 5.0V
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:
All I/O pins set as outputs driven to VSS;
MCLR = VDD;
OSC1 = external square wave, from rail-to-rail (PRI_RUN and PRI_IDLE only).
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 435
PIC18(L)F2X/4XK22
27.8
DC Characteristics:Input/Output Characteristics, PIC18(L)F2X/4XK22
DC CHARACTERISTICS
Param
Symbol
No.
VIL
Characteristic
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA  +125°C
Min
Typ†
Max
Units
Conditions
Input Low Voltage
I/O ports:
D140
with TTL buffer
—
V
D141
with Schmitt Trigger
—
V
D142
MCLR
—
V
D143
OSC1
—
V
HS, HSPLL modes
D144
D145
D146
OSC1
OSC1
TXCKI
—
—
—
V
V
V
RC, EC modes(1)
XT, LP modes
with TTL buffer
—
V
with Schmitt Trigger:
—
—
V
V
2.4V < VDD < 3.6V
VDD < 2.4V
MCLR
—
—
V
V
2.4V < VDD < 3.6V
VDD < 2.4V
D150
OSC1
—
V
HS, HSPLL modes
D151
D152
D153
D154
OSC1
OSC1
OSC1
TXCKI
—
—
—
—
V
V
V
V
EC mode
RC mode(1)
XT, LP modes
VIH
Input High Voltage
I/O ports:
D147
D148
VIH
D149
VIH
IIL
D155
VSS VPIN VDD,
Pin at highimpedance
Input Leakage I/O and
MCLR(2),(3)
I/O ports
5
10
30
100
nA
nA
nA
nA
+25°C
+60°C
+85°C
+125°C
10
35
200
400
nA
nA
nA
nA
+25°C
+60°C
+85°C
+125°C
10
25
70
300
nA
nA
nA
nA
+25°C
+60°C
+85°C
+125°C
Input Leakage RA2
D156
IIL
D157
IIL
Input Leakage RA3
Note 1:
2:
3:
4:
In RC oscillator configuration, the OSC1/CLKIN 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.
Parameter is characterized but not tested.
DS41412C-page 436
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.8
DC Characteristics:Input/Output Characteristics, PIC18(L)F2X/4XK22 (Continued)
DC CHARACTERISTICS
Param
Symbol
No.
D158
Characteristic
IPU
Weak Pull-up Current
IPURB
PORTB weak pull-up
current
VOL
Output Low Voltage
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C TA  +125°C
Min
Units
Conditions
90
A
VDD = 3.0V, VPIN =
VSS
Typ†
Max
D159
I/O ports
—
V
IOL = 8.5 mA, VDD
= 3.0V,
-40C to +85C
D160
OSC2/CLKOUT
(RC, RCIO, EC, ECIO
modes)
—
V
IOL = 1.6 mA, VDD
= 3.0V,
-40C to +85C
VOH
Output High Voltage(3)
D161
I/O ports
—
V
IOH = -3.0 mA, VDD
= 3.0V,
-40C to +85C
D162
OSC2/CLKOUT
(RC, RCIO, EC, ECIO
modes)
—
V
IOH = -1.3 mA, VDD
= 3.0V,
-40C to +85C
Capacitive Loading
Specs
on Output Pins
D163(4) COSC2
OSC2 pin
—
pF
In XT, HS and LP
modes when
external clock is
used to drive
OSC1
D164
CIO
All I/O pins and OSC2
(in RC mode)
—
pF
To meet the AC
Timing
Specifications
D165
CB
SCL, SDA
—
pF
I2C™ Specification
Note 1:
2:
3:
4:
In RC oscillator configuration, the OSC1/CLKIN 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.
Parameter is characterized but not tested.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 437
PIC18(L)F2X/4XK22
27.9
Memory Programming Requirements
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C  TA  +125°C
DC CHARACTERISTICS
Param
No.
Sym
Characteristic
Min
Typ†
Max
Units
Conditions
Internal Program Memory
Programming Specifications(1)
D170
VPP
Voltage on MCLR/VPP/RE3 pin
8
—
9
V
D171
IDDP
Supply Current during
Programming
—
—
10
mA
(Note 3), (Note 4)
Data EEPROM Memory
D172
ED
Byte Endurance
100K
—
—
E/W
D173
VDRW
VDD for Read/Write (PIC18LF)
1.8
—
3.6
V
D174
VDRW
VDD for Read/Write (PIC18F)
1.8
—
5.5
V
-40C to +85C
Using EECON to
read/write
D175
TDEW
Erase/Write Cycle Time
—
4
—
ms
D176
TRETD Characteristic Retention
40
—
—
Year
Provided no other
specifications are violated
D177
TREF
1M
10M
—
E/W
-40°C to +85°C
-40C to +85C (Note 5)
Number of Total Erase/Write
Cycles before Refresh(2)
Program Flash Memory
D178
EP
Cell Endurance
10K
—
—
E/W
D179
VPR
VDD for Read (PIC18LF)
1.8
—
3.6
V
D180
VPR
VDD for Read (PIC18F)
1.8
—
5.5
V
D181
VIW
VDD for Row Erase or Write
(PIC18LF)
2.2
—
3.6
V
D182
VIW
VDD for Row Erase or Write
(PIC18F)
2.2
—
5.5
V
D183
TIW
Self-timed Write Cycle Time
—
2
—
ms
D184
TRETD Characteristic Retention
40
—
—
Year
Provided no other
specifications are violated
† Data in “Typ” column is at 3.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: These specifications are for programming the on-chip program memory through the use of table write instructions.
2: Refer to Section 7.8 “Using the Data EEPROM” for a more detailed discussion on data EEPROM
endurance.
3: Required only if single-supply programming is disabled.
4: The MPLAB ICD 2 does not support variable VPP output. Circuitry to limit the ICD 2 VPP voltage must be
placed between the ICD 2 and target system when programming or debugging with the ICD 2.
5: Self-write and Block Erase.
DS41412C-page 438
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.10 Analog Characteristics
TABLE 27-1:
COMPARATOR SPECIFICATIONS
Operating Conditions: 1.8V < VDD < 5.5V, -40°C < TA < +125°C (unless otherwise stated)
Param
No.
CM01
Sym
VIOFF
Characteristics
Min
Input Offset Voltage
CM02
VICM
Input Common-mode Voltage
CM03
CMRR
Common-mode Rejection Ratio
CM04
TRESP
Response Time
TMC2OV
CM05
*
Note 1:
Comparator Mode Change to
Output Valid*
Typ
Max
Units
Comments
—
12
mV
High-Power mode
—
18
mV
Low-Power mode
—
VDD
V
—
—
dB
—
200
ns
High-Power mode(1)
—
300
ns
Low-Power mode
—
—
s
These parameters are characterized but not tested.
Response time measured with one comparator input at VDD/2, while the other input transitions from VSS to VDD.
TABLE 27-2:
DIGITAL-TO-ANALOG CONVERTER (DAC) SPECIFICATIONS
Operating Conditions: 1.8V < VDD < 5.5V, -40°C < TA < +125°C (unless otherwise stated)
Param
No.
Sym
Characteristics
Min
Typ
Max
Units
VDD/32
—
V
CV01*
CLSB
Step Size(2)
—
CV02*
CACC
Absolute Accuracy
—
—
1/2
LSb
CV03*
CR
Unit Resistor Value (R)
—
5k
—

CST
Time(1)
—
—
10
s
CV04*
*
Note 1:
2:
Settling
Comments
These parameters are characterized but not tested.
Settling time measured while CVRR = 1 and CVR3:CVR0 transitions from ‘0000’ to ‘1111’.
See Section 22.0 “Digital-to-Analog Converter (DAC) Module” for more information.
TABLE 27-3:
FIXED VOLTAGE REFERENCE (FVR) SPECIFICATIONS
Operating Conditions: 1.8V < VDD < 3.6V, -40°C < TA < +125°C (unless otherwise stated)
VR Voltage Reference Specifications
Param
No.
VR01
Sym
VROUT
VR04*
TSTABLE
*
Characteristics
VR voltage output
Settling Time
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Min
Typ
Max
Units
Comments
0.92
1.024
1.13
V
1x output, VDD 1.8V
1.84
2.048
2.26
V
2x output, VDD 2.5V
3.70
4.096
4.50
V
4x output, VDD 4.75V
—
25
100
s
0 to 125°C
These parameters are characterized but not tested.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 439
PIC18(L)F2X/4XK22
FIGURE 27-3:
HIGH/LOW-VOLTAGE DETECT CHARACTERISTICS
VDD
(HLVDIF can be
cleared by software)
VHLVD
(HLVDIF set by hardware)
HLVDIF
TABLE 27-4:
HIGH/LOW-VOLTAGE DETECT CHARACTERISTICS
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C  TA  +125°C
Param
Symbol
No.
Characteristic
HLVDL<3:0>
Min
Typ†
Max
Units
HLVD Voltage on VDD
Transition High-toLow
0000
1.80
V
0001
2.05
V
0010
2.25
V
0011
2.40
V
0100
2.50
V
0101
2.75
V
0110
2.80
V
0111
2.95
V
1000
3.25
V
1001
3.45
V
1010
3.65
V
1011
3.80
V
1100
4.10
V
1101
4.35
V
1110
4.70
V
1111
V(HLVDIN pin)
v
Conditions
† Production tested at TAMB = 25°C. Specifications over temperature limits ensured by characterization.
DS41412C-page 440
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.11 AC (Timing) Characteristics
27.11.1
TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created
using one of the following formats:
1. TppS2ppS
2. TppS
T
F
Frequency
Lowercase letters (pp) and their meanings:
pp
cc
CCP1
ck
CLKOUT
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
 2010 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
T13CKI
WR
P
R
V
Z
Period
Rise
Valid
High-impedance
High
Low
High
Low
SU
Setup
STO
Stop condition
Preliminary
DS41412C-page 441
PIC18(L)F2X/4XK22
27.11.2
TIMING CONDITIONS
The temperature and voltages specified in Table 27-5
apply to all timing specifications unless otherwise
noted. Figure 27-4 specifies the load conditions for the
timing specifications.
TABLE 27-5:
TEMPERATURE AND VOLTAGE SPECIFICATIONS – AC
AC CHARACTERISTICS
FIGURE 27-4:
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA +125°C
Operating voltage VDD range as described in DC spec Section 27.1 and
Section 27.9.
LOAD CONDITIONS FOR DEVICE TIMING SPECIFICATIONS
Load Condition 1
Load Condition 2
VDD/2
RL
CL
Pin
VSS
DS41412C-page 442
CL
Pin
Legend:
RL = 464
CL = 50 pF
Preliminary
VSS
for all pins except OSC2/CLKOUT
and including D and E outputs as ports
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
27.11.3
TIMING DIAGRAMS AND SPECIFICATIONS
FIGURE 27-5:
EXTERNAL CLOCK TIMING (ALL MODES EXCEPT PLL)
Q4
Q1
Q2
Q3
Q4
Q1
OSC1
1
3
3
4
4
2
CLKOUT
TABLE 27-6:
Param.
No.
1A
EXTERNAL CLOCK TIMING REQUIREMENTS
Symbol
FOSC
Characteristic
External CLKIN
Frequency(1)
Oscillator Frequency(1)
1
TOSC
External CLKIN Period(1)
Oscillator Period
(1)
Min
Max
Units
Conditions
DC
DC
0.5
16
MHz
MHz
DC
64
MHz
EC, ECIO Oscillator mode (low power)
EC, ECIO Oscillator mode (medium
power)
EC, ECIO Oscillator mode (high power)
DC
4
MHz
RC Oscillator mode
0.1
4
MHz
XT Oscillator mode
1
4
MHz
HS Oscillator mode, VDD 2.7V
1
20
MHz
HS Oscillator mode, VDD > 2.7V
5
200
kHz
LP Oscillator mode
2.0
62.5
—
—
s
ns
15.6
—
ns
EC, ECIO Oscillator mode (low power)
EC, ECIO Oscillator mode (medium
power)
EC, ECIO Oscillator mode (high power)
250
—
ns
RC Oscillator mode
250
10,000
ns
XT Oscillator mode
40
62.5
250
250
ns
ns
HS Oscillator mode
HS + PLL Oscillator mode,
5
200
s
LP Oscillator mode
2
TCY
Instruction Cycle Time(1)
62.5
—
ns
TCY = 4/FOSC
3
TOSL,
TOSH
External Clock in (OSC1)
High or Low Time
30
—
ns
XT Oscillator mode
2.5
—
s
LP Oscillator mode
10
—
ns
HS Oscillator mode
TOSR,
TOSF
External Clock in (OSC1)
Rise or Fall Time
—
20
ns
XT Oscillator mode
4
Note 1:
—
50
ns
LP Oscillator mode
—
7.5
ns
HS Oscillator mode
Instruction cycle period (TCY) equals four times the input oscillator time base period for all configurations
except PLL. 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/CLKIN pin. When an external clock
input is used, the “max.” cycle time limit is “DC” (no clock) for all devices.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 443
PIC18(L)F2X/4XK22
TABLE 27-7:
PLL CLOCK TIMING SPECIFICATIONS (VDD = 1.8V TO 5.5V)
Param.
No.
Sym
F10
FOSC Oscillator Frequency Range
F11
FSYS
Characteristic
Min
On-Chip VCO System Frequency
Typ†
Max
Units
Conditions
4
—
5
MHz VDD = 1.8-3.0V
4
—
16
MHz VDD = 3.0-3.6V,
-40°C to +125°C
PIC18LF2X/4XK22
4
—
16
MHz VDD = 3.0-5.5V,
-40°C to +125°C
PIC18F2X/4XK22
16
—
20
MHz VDD = 1.8-3.0V
16
—
64
MHz VDD = 3.0-3.6V,
-40°C to +125°C
PIC18LF2X/4XK22
16
—
64
MHz VDD = 3.0-5.5V,
-40°C to +125°C
PIC18F2X/4XK22
F12
trc
PLL Start-up Time (Lock Time)
—
—
2
ms
F13
CLK
CLKOUT Stability (Jitter)
-2
—
+2
%
† Data in “Typ” column is at 3V, 25C unless otherwise stated. These parameters are for design guidance
only and are not tested.
TABLE 27-8:
AC CHARACTERISTICS:INTERNAL OSCILLATORS ACCURACY PIC18(L)F46K22
PIC18(L)F46K22
Param.
No.
OA1
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C  TA  +125°C
Min
Max
Units
Conditions
HFINTOSC Accuracy @ Freq = 16 MHz, 8 MHz, 4 MHz, 2 MHz, 1 MHz, 500 kHz, 250 kHz(1)
-2
OA2
Typ
0
+2
%
+0°C to +70°C
-3
—
+2
%
+70°C to +85°C
-5
—
+5
%
-40°C to 0°C and
+85°C to 125°C
—
35.938
kHz
-40°C to +125°C
LFINTOSC Accuracy @ Freq = 31 kHz
26.562
Legend: Shading of rows is to assist in readability of the table.
Note 1: Frequency calibrated at 25°C. OSCTUNE register can be used to compensate for temperature drift.
DS41412C-page 444
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
FIGURE 27-6:
CLKOUT AND I/O TIMING
Q1
Q4
Q2
Q3
OSC1
11
10
CLKOUT
13
19
14
12
18
16
I/O pin
(Input)
15
17
I/O pin
(Output)
Note:
20, 21
Refer to Figure 27-4 for load conditions.
TABLE 27-9:
Param.
No.
New Value
Old Value
CLKOUT AND I/O TIMING REQUIREMENTS
Symbol
Characteristic
Min
Typ
Max
Units
Conditions
10
TosH2ckL
OSC1  to CLKOUT 
—
75
200
ns
(Note 1)
11
TosH2ckH
OSC1  to CLKOUT 
—
75
200
ns
(Note 1)
12
TckR
CLKOUT Rise Time
—
35
100
ns
(Note 1)
13
TckF
CLKOUT Fall Time
—
35
100
ns
(Note 1)
14
TckL2ioV
CLKOUT  to Port Out Valid
—
—
0.5 TCY + 20
ns
(Note 1)
15
TioV2ckH
Port In Valid before CLKOUT 
0.25 TCY + 25
—
—
ns
(Note 1)
16
TckH2ioI
Port In Hold after CLKOUT 
0
—
—
ns
(Note 1)
17
TosH2ioV
OSC1  (Q1 cycle) to Port Out Valid
—
50
150
ns
18
TosH2ioI
OSC1  (Q2 cycle) to Port Input Invalid
(I/O in hold time)
100
—
—
ns
19
TioV2osH
Port Input Valid to OSC1 (I/O in setup time)
0
—
—
ns
20
TioR
Port Output Rise Time
—
10
25
ns
21
TioF
Port Output Fall Time
—
10
25
ns
22†
TINP
INTx pin High or Low Time
20
—
—
ns
23†
TRBP
RB<7:4> Change KBIx High or Low Time
TCY
—
—
ns
†
Note 1:
These parameters are asynchronous events not related to any internal clock edges.
Measurements are taken in RC mode, where CLKOUT output is 4 x TOSC.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 445
PIC18(L)F2X/4XK22
FIGURE 27-7:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Time-out
Internal
Reset
Watchdog
Timer
Reset
31
34
34
I/O pins
Note:
Refer to Figure 27-4 for load conditions.
FIGURE 27-8:
VDD
BROWN-OUT RESET TIMING
BVDD
35
VBGAP = 1.2V
VIVRST
Enable Internal
Reference Voltage
Internal Reference
Voltage Stable
DS41412C-page 446
36
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-10: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET REQUIREMENTS
Param.
Symbol
No.
Characteristic
Min
Typ
Max
Units
2
—
—
s
Conditions
30
TmcL
MCLR Pulse Width (low)
31
TWDT
Watchdog Timer Time-out Period
(no postscaler)
3.5
4.1
4.7
ms
1:1 prescaler
32
TOST
Oscillation Start-up Timer Period
1024
TOSC
—
1024 TOSC
—
TOSC = OSC1 period
33
TPWRT
Power-up Timer Period
54.8
64.4
74.1
ms
34
TIOZ
I/O High-Impedance from MCLR
Low or Watchdog Timer Reset
—
2
—
s
35
TBOR
Brown-out Reset Pulse Width
200
—
—
s
36
TIVRST
Internal Reference Voltage Stable
—
25
35
s
37
THLVD
High/Low-Voltage Detect Pulse
Width
200
—
—
s
38
TCSD
CPU Start-up Time
5
—
10
s
39
TIOBST
Time for HF-INTOSC to Stabilize
—
0.25
1
ms
FIGURE 27-9:
VDD  BVDD (see
D005)
VDD  VHLVD
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
41
40
42
T1OSO/T13CKI
46
45
47
48
TMR0 or
TMR1
Note:
Refer to Figure 27-4 for load conditions.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 447
PIC18(L)F2X/4XK22
TABLE 27-11: TIMER0 AND TIMER1/3/5 EXTERNAL CLOCK REQUIREMENTS
Param.
No.
40
Symbol
Characteristic
Tt0H
T0CKI High Pulse Width
No prescaler
Min
Max
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
With prescaler
41
Tt0L
T0CKI Low Pulse Width
No prescaler
With prescaler
42
Tt0P
T0CKI Period
No prescaler
With prescaler
45
Tt1H
TxCKI High
Time
Synchronous, no prescaler
0.5 TCY + 20
—
ns
10
—
ns
Synchronous,
with prescaler
Asynchronous
46
47
48
Tt1L
Tt1P
—
ns
—
ns
10
—
ns
Synchronous, no prescaler
Asynchronous
30
—
ns
TxCKI Input
Period
Synchronous
Greater of:
20 ns or
(TCY + 40)/N
—
ns
Asynchronous
60
—
ns
DC
50
kHz
2 TOSC
7 TOSC
—
Synchronous,
with prescaler
Ft1
TxCKI Clock Input Frequency Range
Tcke2tmrI
Delay from External TxCKI Clock Edge to Timer
Increment
FIGURE 27-10:
30
0.5 TCY + 5
TxCKI Low
Time
Conditions
N = prescale
value
(1, 2, 4,..., 256)
N = prescale
value (1, 2, 4, 8)
CAPTURE/COMPARE/PWM TIMINGS (ALL CCP MODULES)
CCPx
(Capture Mode)
50
51
52
CCPx
(Compare or PWM Mode)
53
Note:
54
Refer to Figure 27-4 for load conditions.
DS41412C-page 448
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-12: CAPTURE/COMPARE/PWM REQUIREMENTS (ALL CCP MODULES)
Param .
Symbol
No.
50
TccL
51
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
52
TccP
CCPx Input Period
53
TccR
CCPx Output Fall Time
—
25
ns
54
TccF
CCPx Output Fall Time
—
25
ns
FIGURE 27-11:
Conditions
N = prescale
value (1, 4 or
16)
EXAMPLE SPI MASTER MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
71
72
78
79
79
78
SCK
(CKP = 1)
80
bit 6 - - - - - -1
MSb
SDO
LSb
75, 76
SDI
MSb In
bit 6 - - - -1
LSb In
74
73
Note:
Refer to Figure 27-4 for load conditions.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 449
PIC18(L)F2X/4XK22
TABLE 27-13: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 0)
Param.
No.
Symbol
Characteristic
Min
Max Units
70
TssL2scH,
TssL2scL
SS  to SCK  or SCK  Input
71
TscH
SCK Input High Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
SCK Input Low Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
100
—
ns
1.5 TCY + 40
—
ns
100
—
ns
—
25
ns
71A
72
TscL
72A
TCY
—
ns
73
TdiV2scH,
TdiV2scL
Setup Time of SDI Data Input to SCK Edge
73A
Tb2b
Last Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
74
TscH2diL,
TscL2diL
Hold Time of SDI Data Input to SCK Edge
75
TdoR
SDO Data Output Rise Time
76
TdoF
SDO Data Output Fall Time
—
25
ns
78
TscR
SCK Output Rise Time
(Master mode)
—
25
ns
79
TscF
SCK Output Fall Time (Master mode)
—
25
ns
80
TscH2doV,
TscL2doV
SDO Data Output Valid after SCK Edge
—
50
ns
Note 1:
2:
Conditions
(Note 1)
(Note 1)
(Note 2)
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
FIGURE 27-12:
EXAMPLE SPI MASTER MODE TIMING (CKE = 1)
SS
81
SCK
(CKP = 0)
71
72
79
73
SCK
(CKP = 1)
80
78
MSb
SDO
bit 6 - - - - - -1
LSb
bit 6 - - - -1
LSb In
75, 76
SDI
MSb In
74
Note:
Refer to Figure 27-4 for load conditions.
DS41412C-page 450
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-14: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 1)
Param.
No.
71
Symbol
TscH
71A
72
TscL
72A
Characteristic
Min
Max Units
SCK Input High Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
SCK Input Low Time
(Slave mode)
Continuous
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
100
—
ns
1.5 TCY + 40
—
ns
100
—
ns
73
TdiV2scH,
TdiV2scL
Setup Time of SDI Data Input to SCK Edge
73A
Tb2b
Last Clock Edge of Byte 1 to the 1st Clock Edge
of Byte 2
74
TscH2diL,
TscL2diL
Hold Time of SDI Data Input to SCK Edge
75
TdoR
SDO Data Output Rise Time
—
25
ns
76
TdoF
SDO Data Output Fall Time
—
25
ns
78
TscR
SCK Output Rise Time
(Master mode)
—
25
ns
79
TscF
SCK Output Fall Time (Master mode)
—
25
ns
80
TscH2doV,
TscL2doV
SDO Data Output Valid after SCK Edge
—
50
ns
81
TdoV2scH,
TdoV2scL
SDO Data Output Setup to SCK Edge
TCY
—
ns
Note 1:
2:
Conditions
(Note 1)
(Note 1)
(Note 2)
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
FIGURE 27-13:
EXAMPLE SPI SLAVE MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
83
71
72
78
79
79
78
SCK
(CKP = 1)
80
MSb
SDO
bit 6 - - - - - -1
LSb
77
75, 76
MSb In
SDI
73
Note:
bit 6 - - - -1
LSb In
74
Refer to Figure 27-4 for load conditions.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 451
PIC18(L)F2X/4XK22
TABLE 27-15: EXAMPLE SPI MODE REQUIREMENTS (SLAVE MODE TIMING, CKE = 0)
Param.
No.
Symbol
Characteristic
Min
Max
Units
TCY
—
ns
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
Continuous
1.25 TCY + 30
—
ns
70
TssL2scH,
TssL2scL
SS  to SCK  or SCK  Input
71
TscH
SCK Input High Time
(Slave mode)
TscL
SCK Input Low Time
(Slave mode)
TdiV2scH,
TdiV2scL
Setup Time of SDI Data Input to SCK Edge
73A
Tb2b
Last Clock Edge of Byte 1 to the First Clock Edge of Byte 2
74
TscH2diL,
TscL2diL
Hold Time of SDI Data Input to SCK Edge
75
TdoR
76
TdoF
71A
72
72A
73
Continuous
Single Byte
40
—
ns
100
—
ns
1.5 TCY + 40
—
ns
100
—
ns
SDO Data Output Rise Time
—
25
ns
SDO Data Output Fall Time
—
25
ns
77
TssH2doZ
SS to SDO Output High-Impedance
10
50
ns
78
TscR
SCK Output Rise Time (Master mode)
—
25
ns
79
TscF
SCK Output Fall Time (Master mode)
—
25
ns
80
TscH2doV,
TscL2doV
SDO Data Output Valid after SCK Edge
—
50
ns
83
TscH2ssH,
TscL2ssH
SS  after SCK edge
1.5 TCY + 40
—
ns
Note 1:
2:
Conditions
(Note 1)
(Note 1)
(Note 2)
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
FIGURE 27-14:
EXAMPLE SPI SLAVE MODE TIMING (CKE = 1)
82
SS
SCK
(CKP = 0)
70
83
71
72
SCK
(CKP = 1)
80
MSb
SDO
bit 6 - - - - - -1
LSb
75, 76
SDI
Note:
MSb In
77
bit 6 - - - -1
LSb In
74
Refer to Figure 27-4 for load conditions.
DS41412C-page 452
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-16: EXAMPLE SPI SLAVE MODE REQUIREMENTS (CKE = 1)
Param.
No.
Symbol
Characteristic
70
TssL2scH,
TssL2scL
SS  to SCK  or SCK  Input
71
TscH
SCK Input High Time
(Slave mode)
TscL
SCK Input Low Time
(Slave mode)
73A
Tb2b
Last Clock Edge of Byte 1 to the First Clock Edge of Byte 2
74
TscH2diL,
TscL2diL
Hold Time of SDI Data Input to SCK Edge
75
TdoR
SDO Data Output Rise Time
76
TdoF
77
TssH2doZ
78
TscR
79
80
71A
72
72A
Continuous
Min
Max
Units
TCY
—
ns
1.25 TCY + 30
—
ns
Single Byte
40
—
ns
Continuous
1.25 TCY + 30
—
ns
(Note 1)
40
—
ns
(Note 1)
1.5 TCY + 40
—
ns
(Note 2)
100
—
ns
—
25
ns
SDO Data Output Fall Time
—
25
ns
SS to SDO Output High-Impedance
10
50
ns
SCK Output Rise Time
(Master mode)
—
25
ns
TscF
SCK Output Fall Time (Master mode)
—
25
ns
TscH2doV,
TscL2doV
SDO Data Output Valid after SCK Edge
—
50
ns
82
TssL2doV
SDO Data Output Valid after SS  Edge
—
50
ns
83
TscH2ssH,
TscL2ssH
SS  after SCK Edge
1.5 TCY + 40
—
ns
Note 1:
2:
Single Byte
Conditions
Requires the use of Parameter #73A.
Only if Parameter #71A and #72A are used.
I2C™ BUS START/STOP BITS TIMING
FIGURE 27-15:
SCL
91
93
90
92
SDA
Stop
Condition
Start
Condition
Note:
Refer to Figure 27-4 for load conditions.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 453
PIC18(L)F2X/4XK22
TABLE 27-17: I2C™ BUS START/STOP BITS REQUIREMENTS (SLAVE MODE)
Param.
Symbol
No.
90
91
92
93
TSU:STA
THD:STA
TSU:STO
Characteristic
Max
Units
Conditions
ns
Only relevant for Repeated
Start condition
ns
After this period, the first
clock pulse is generated
Start Condition
100 kHz mode
4700
—
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
400 kHz mode
600
—
100 kHz mode
4000
—
400 kHz mode
600
—
THD:STO Stop Condition
Hold Time
FIGURE 27-16:
Min
ns
ns
I2C™ BUS DATA TIMING
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
Note:
Refer to Figure 27-4 for load conditions.
DS41412C-page 454
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-18: I2C™ BUS DATA REQUIREMENTS (SLAVE MODE)
Param.
Symbol
No.
100
THIGH
Characteristic
Clock High Time
Min
Max
Units
Conditions
100 kHz mode
4.0
—
s
Must operate at a minimum
of 1.5 MHz
400 kHz mode
0.6
—
s
Must operate at a minimum
of 10 MHz
1.5 TCY
—
100 kHz mode
4.7
—
s
Must operate at a minimum
of 1.5 MHz
400 kHz mode
1.3
—
s
Must operate at a minimum
of 10 MHz
1.5 TCY
—
SSP Module
101
TLOW
Clock Low Time
SSP Module
102
TR
103
TF
SDA and SCL Rise 100 kHz mode
Time
400 kHz mode
SDA and SCL Fall
Time
—
1000
ns
20 + 0.1 CB
300
ns
100 kHz mode
—
300
ns
400 kHz mode
20 + 0.1 CB
300
ns
CB is specified to be from
10 to 400 pF
4.7
—
s
Only relevant for Repeated
Start condition
90
TSU:STA Start Condition
Setup Time
100 kHz mode
400 kHz mode
0.6
—
s
91
THD:STA Start Condition
Hold Time
100 kHz mode
4.0
—
s
400 kHz mode
0.6
—
s
106
THD:DA
100 kHz mode
0
—
ns
T
Data Input Hold
Time
400 kHz mode
0
0.9
s
107
TSU:DAT Data Input Setup
Time
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
92
TSU:STO Stop Condition
Setup Time
100 kHz mode
4.7
—
s
400 kHz mode
0.6
—
s
109
TAA
Output Valid from
Clock
100 kHz mode
—
3500
ns
400 kHz mode
—
—
ns
110
TBUF
Bus Free Time
100 kHz mode
4.7
—
s
400 kHz mode
1.3
—
s
—
400
pF
D102
CB
Note 1:
2:
Bus Capacitive Loading
CB is specified to be from
10 to 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 SCL 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 SCL signal. If such a device does stretch the LOW period of the SCL signal, it must
output the next data bit to the SDA line, TR max. + TSU:DAT = 1000 + 250 = 1250 ns (according to the
standard mode I2C bus specification), before the SCL line is released.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 455
PIC18(L)F2X/4XK22
FIGURE 27-17:
MASTER SSP I2C™ BUS START/STOP BITS TIMING WAVEFORMS
SCL
93
91
90
92
SDA
Stop
Condition
Start
Condition
Note:
Refer to Figure 27-4 for load conditions.
TABLE 27-19: MASTER SSP I2C™ BUS START/STOP BITS REQUIREMENTS
Param.
Symbol
No.
90
TSU:STA
Characteristic
Start Condition
Setup Time
91
THD:STA Start Condition
Hold Time
92
TSU:STO Stop Condition
Setup Time
93
THD:STO Stop Condition
Hold Time
Min
Max
Units
100 kHz mode
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
Note 1: Maximum pin capacitance = 10 pF for all I2C pins.
FIGURE 27-18:
MASTER SSP I2C™ BUS DATA TIMING
103
102
100
101
SCL
90
106
91
107
92
SDA
In
109
109
110
SDA
Out
Note:
DS41412C-page 456
Refer to Figure 27-4 for load conditions.
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-20: MASTER SSP I2C™ BUS DATA REQUIREMENTS
Param.
Symbol
No.
100
THIGH
Characteristic
Min
Max
Units
Clock High Time 100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
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 MHz mode(1)
2(TOSC)(BRG + 1)
—
ms
100 kHz mode
—
1000
ns
400 kHz mode
20 + 0.1 CB
300
ns
1 MHz
101
102
103
90
91
106
107
92
TLOW
TR
TF
TSU:STA
SDA and SCL
Rise Time
SDA and SCL
Fall Time
Start Condition
Setup Time
1 MHz mode(1)
—
300
ns
100 kHz mode
—
300
ns
400 kHz mode
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
THD:DAT Data Input
Hold Time
100 kHz mode
0
—
ns
400 kHz mode
0
0.9
ms
TSU:DAT
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
THD:STA Start Condition
Hold Time
Data Input
Setup Time
TSU:STO Stop Condition
Setup Time
100 kHz mode
2(TOSC)(BRG + 1)
—
ms
400 kHz mode
2(TOSC)(BRG + 1)
—
ms
mode(1)
1 MHz
109
110
D102
Note 1:
2:
TAA
TBUF
CB
Output Valid
from Clock
Bus Free Time
2(TOSC)(BRG + 1)
—
ms
100 kHz mode
—
3500
ns
400 kHz mode
—
1000
ns
1 MHz mode(1)
—
—
ns
100 kHz mode
4.7
—
ms
400 kHz mode
1.3
—
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
SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit
to the SDA line, parameter 102 + parameter 107 = 1000 + 250 = 1250 ns (for 100 kHz mode), before the
SCL line is released.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 457
PIC18(L)F2X/4XK22
FIGURE 27-19:
EUSART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
TXx/CKx
pin
121
121
RXx/DTx
pin
120
Note:
122
Refer to Figure 27-4 for load conditions.
TABLE 27-21: EUSART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param.
No.
Symbol
Characteristic
Min
Max
Units
120
TckH2dtV SYNC XMIT (MASTER & 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 27-20:
TXx/CKx
pin
RXx/DTx
Conditions
EUSART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
125
pin
126
Note:
Refer to Figure 27-4 for load conditions.
TABLE 27-22: EUSART SYNCHRONOUS RECEIVE REQUIREMENTS
Param.
No.
Symbol
Characteristic
Min
Max
Units
125
TdtV2ckl
SYNC RCV (MASTER & SLAVE)
Data Setup before CK  (DT setup time)
10
—
ns
126
TckL2dtl
Data Hold after CK  (DT hold time)
15
—
ns
DS41412C-page 458
Preliminary
Conditions
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
TABLE 27-23: A/D CONVERTER CHARACTERISTICS:PIC18(L)F2X/4XK22
Param .
Symbol
No.
Characteristic
Min
Typ
Max
Units
Conditions
A01
NR
Resolution
—
—
10
bits
-40°C to +85°C,
VREF  2.0V
A03
EIL
Integral Linearity Error
—
±0.5
—
LSb
-40°C to +85°C,
VREF  2.0V
A04
EDL
Differential Linearity Error
—
±0.4
—
LSb
-40°C to +85°C,
VREF  2.0V
A06
EOFF
Offset Error
—
0.4
—
LSb
-40°C to +85°C,
VREF  2.0V
A07
EGN
Gain Error
—
0.3
—
LSb
-40°C to +85°C,
VREF  2.0V
A08
ETOTL
Total Error
—
1
—
LSb
-40°C to +85°C,
VREF  2.0V
A20
VREF
Reference Voltage Range
(VREFH – VREFL)
1.8
2.0
—
—
—
—
V
V
A21
VREFH
Reference Voltage High
VDD/2
—
VDD + 0.3
V
A22
VREFL
Reference Voltage Low
VSS – 0.3V
—
VDD/2
V
A25
VAIN
Analog Input Voltage
VREFL
—
VREFH
V
A30
ZAIN
Recommended Impedance of
Analog Voltage Source
—
—
3
k
Note 1:
2:
Absolute Minimum
Minimum for 1LSb
Accuracy
-40°C to +85°C
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-/CVREF pin or VSS, whichever is selected as the VREFL source.
FIGURE 27-21:
A/D CONVERSION TIMING
BSF ADCON0, GO
(Note 2)
131
Q4
A/D CLK
130
132
9
A/D DATA
8
7
.. .
...
2
OLD_DATA
ADRES
1
0
NEW_DATA
TCY
ADIF
GO
DONE
SAMPLING STOPPED
SAMPLE
Note 1:
2:
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.
This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 459
PIC18(L)F2X/4XK22
TABLE 27-24: A/D CONVERSION REQUIREMENTS
Param.
Symbol
No.
130
TAD
131
Characteristic
A/D Clock Period
Min
Max
Units
0.7
25.0(1)
s
TOSC based,
-40C to +85C
0.7
4.0(1)
s
TOSC based,
+85C to +125C
FRC mode, VDD2.0V
1.0
4.0
s
TCNV
Conversion Time
(not including acquisition time) (Note 2)
12
12
TAD
s
132
TACQ
Acquisition Time (Note 3)
1.4
—
135
TSWC
Switching Time from Convert  Sample
—
(Note 4)
136
TDIS
Discharge Time
2
2
Legend:
Note 1:
2:
3:
4:
Conditions
VDD = 3V, Rs = 50
TAD
TBD = To Be Determined
The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.
ADRES register 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 50 .
On the following cycle of the device clock.
DS41412C-page 460
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
28.0
DC AND AC
CHARACTERISTICS GRAPHS
AND TABLES
Graphs and tables are not available at this time.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 461
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 462
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
29.0
PACKAGING INFORMATION
29.1
Package Marking Information
28-Lead SPDIP (300 mil)
Example
PIC18F25K22-E/SP
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
YYWWNNN
e3
0810017
28-Lead SOIC (300 mil)
Example
PIC18F25K22-E/SO e3
0810017
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
YYWWNNN
Example
28-Lead SSOP
PIC18F25K22
-E/SS e3
0810017
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
28-Lead QFN (6mm x 6mm)
Example
XXXXXXXX
XXXXXXXX
YYWWNNN
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
18F25K22
-I/ML
0610017
Customer-specific information or Microchip part number
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.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 463
PIC18(L)F2X/4XK22
Package Marking Information (Continued)
28-Lead UQFN (4mm x 4mm)
Example
XXXXX
XXXXXX
XXXXXX
YWWNNN
PIC18
F23K22
-E/MV e3
810017
40-Lead PDIP (600 mil)
Example
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
YYWWNNN
PIC18F45K22-E/P e3
0810017
40-Lead UQFN (5mm x 5mm)
Example
XXXXXXX
XXXXXXX
XXXXXXX
YYWWNNN
PIC18
F45K22
-I/MV e3
0810017
44-Lead QFN (8mm x 8mm)
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
PIC18
F45K22
-E/ML e3
0810017
44-Lead TQFP (10mm x 10mm)
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
DS41412C-page 464
Example
PIC18
F44 K22
-E/PT e3
0810017
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
29.2
Package Details
The following sections give the technical details of the packages.
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 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 465
PIC18(L)F2X/4XK22
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Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 467
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 2010 Microchip Technology Inc.
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 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 469
PIC18(L)F2X/4XK22
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
DS41412C-page 470
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 471
PIC18(L)F2X/4XK22
30
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DS41412C-page 472
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 473
PIC18(L)F2X/4XK22
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
DS41412C-page 474
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 475
PIC18(L)F2X/4XK22
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PIC18(L)F2X/4XK22
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 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 477
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Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
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 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 479
PIC18(L)F2X/4XK22
NOTES:
DS41412C-page 480
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
APPENDIX A:
REVISION HISTORY
Revision A (February 2010)
Initial release of this document.
Revision B (April 2010)
Updated Figures 2-4, 12-1 and 18-2; Updated
Registers 2-2, 10-4, 10-5, 10-7, 17-2, 24-1 and 24-5;
Updated Sections 10.3.2, 18.8.4, Synchronizing
Comparator Output to Timer1; Updated Sections 27.2,
27-3, 27-4, 27-5, 27-6, 27-7 and 27-9; Updated Tables
27-2, 27-3, 27-4 and 27-7; Other minor corrections.
Revision C (July 2010)
Added 40-pin UQFN diagram; Updated Table 2 and
Table 1-3 to add 40-UQFN column; Updated Table 1-1
to add “40-pin UQFN”; Updated Figure 27-1; Added
Figure 27-2; Updated Table 27-6; Added 40-Lead
UQFN Package Marking Information and Details;
Updated Packaging Information section; Updated
Table B-1 to add “40-pin UQFN”; Updated Product
Identification System section; Other minor corrections.
 2010 Microchip Technology Inc.
Preliminary
DS41412C-page 481
PIC18(L)F2X/4XK22
APPENDIX B:
DEVICE
DIFFERENCES
The differences between the devices listed in this data
sheet are shown in Table B-1.
TABLE B-1:
DEVICE DIFFERENCES
Features(1)
PIC18F23K22 PIC18F24K22
PIC18LF23K22 PIC18LF24K22
PIC18F25K22
PIC18LF25K22
PIC18F26K22
PIC18LF26K22
PIC18F43K22
PIC18LF43K22
PIC18F44K22
PIC18LF44K22
PIC18F45K22
PIC18LF45K22
PIC18F46K22
PIC18LF46K22
Program Memory
(Bytes)
8192
16384
32768
65536
8192
16384
32768
65536
SRAM (Bytes)
512
768
1536
3896
512
768
1536
3896
EEPROM (Bytes)
256
256
256
1024
256
256
256
1024
Interrupt Sources
26
26
33
33
26
26
33
33
Ports A, B, C,
D, E
Ports A, B, C,
D, E
I/O Ports
Ports A, B, C, Ports A, B, C,
(E)
(E)
Ports A, B, C, Ports A, B, C, Ports A, B, C, Ports A, B, C,
(E)
(E)
D, E
D, E
Capture/Compare/PWM
Modules (CCP)
2
2
2
2
2
2
2
2
Enhanced CCP Modules
(ECCP) Full Bridge
1
1
1
1
2
2
2
2
ECCP Module
Half Bridge
2
2
2
2
1
1
1
1
17 input
channels
17 input
channels
17 input
channels
17 input
channels
28 input
channels
28 input
channels
28 input
channels
28 input
channels
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
40-pin PDIP
40-pin UQFN
44-pin TQFP
44-pin QFN
40-pin PDIP
40-pin UQFN
44-pin TQFP
44-pin QFN
40-pin PDIP
40-pin UQFN
44-pin TQFP
44-pin QFN
40-pin PDIP
40-pin UQFN
44-pin TQFP
44-pin QFN
10-bit Analog-to-Digital
Module
Packages
28-pin PDIP
28-pin SOIC
28-pin SSOP
28-pin QFN
28-pin UQFN
28-pin PDIP 28-pin PDIP
28-pin SOIC 28-pin SOIC
28-pin SSOP 28-pin SSOP
28-pin QFN
28-pin QFN
28-pin UQFN
Note 1: PIC18FXXK22: operating voltage, 1.8V-5.5V.
PIC18LFXXK22: operating voltage, 1.8V-3.6V.
DS41412C-page 482
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
INDEX
A
A/D
Analog Port Pins, Configuring .................................. 304
Associated Registers ............................................... 304
Conversions ............................................................. 295
Converter Characteristics ........................................ 459
Discharge ................................................................. 296
Selecting and Configuring Acquisition Time ............ 292
Absolute Maximum Ratings ............................................. 421
AC (Timing) Characteristics ............................................. 441
Load Conditions for Device Timing Specifications ... 442
Parameter Symbology ............................................. 441
Temperature and Voltage Specifications ................. 442
Timing Conditions .................................................... 442
AC Characteristics
Internal RC Accuracy ............................................... 444
Access Bank
Mapping with Indexed Literal Offset Mode ................. 94
ACKSTAT ........................................................................ 242
ACKSTAT Status Flag ..................................................... 242
ADC ................................................................................. 291
Acquisition Requirements ........................................ 302
Block Diagram .......................................................... 291
Calculating Acquisition Time .................................... 302
Channel Selection .................................................... 292
Configuration ............................................................ 292
Conversion Clock ..................................................... 293
Conversion Procedure ............................................. 297
Internal Sampling Switch (RSS) IMPEDANCE ............. 302
Interrupts .................................................................. 293
Operation ................................................................. 295
Operation During Sleep ........................................... 296
Port Configuration .................................................... 292
Power Management ................................................. 296
Reference Voltage (VREF) ........................................ 292
Result Formatting ..................................................... 294
Source Impedance ................................................... 302
Special Event Trigger ............................................... 296
Starting an A/D Conversion ..................................... 294
ADCON0 Register ............................................................ 298
ADCON1 Register ............................................................ 299
ADCON2 Register ............................................................ 300
ADDFSR .......................................................................... 410
ADDLW ............................................................................ 373
ADDULNK ........................................................................ 410
ADDWF ............................................................................ 373
ADDWFC ......................................................................... 374
ADRESH Register (ADFM = 0) ........................................ 301
ADRESH Register (ADFM = 1) ........................................ 301
ADRESL Register (ADFM = 0) ......................................... 301
ADRESL Register (ADFM = 1) ......................................... 301
Analog Input Connection Considerations ......................... 312
Analog-to-Digital Converter. See ADC
ANDLW ............................................................................ 374
ANDWF ............................................................................ 375
Assembler
MPASM Assembler .................................................. 418
B
Bank Select Register (BSR) ............................................... 76
BAUDCON Register ......................................................... 274
BC .................................................................................... 375
BCF .................................................................................. 376
 2010 Microchip Technology Inc.
BF ............................................................................ 242, 244
BF Status Flag ......................................................... 242, 244
Block Diagrams
(CCP) Capture Mode Operation .............................. 178
ADC ......................................................................... 291
ADC Transfer Function ............................................ 303
Analog Input Model .......................................... 303, 312
CCP PWM ............................................................... 184
Comparator 1 ........................................................... 306
Compare .................................................................. 181
Crystal Operation ....................................................... 35
CTMU ...................................................................... 317
CTMU Current Source Calibration Circuit ............... 320
CTMU Typical Connections and Internal
Configuration for Pulse Delay Generation ....... 328
CTMU Typical Connections and Internal
Configuration for Time Measurement .............. 327
Digital-to-Analog Converter (DAC) .......................... 340
EUSART Receive .................................................... 264
EUSART Transmit ................................................... 263
External POR Circuit (Slow VDD Power-up) .............. 61
External RC Mode ..................................................... 36
Fail-Safe Clock Monitor (FSCM) ................................ 44
Generic I/O Port ....................................................... 133
High/Low-Voltage Detect with External Input .......... 344
Interrupt Logic .......................................................... 114
On-Chip Reset Circuit ................................................ 59
PIC18F46K22 ............................................................ 16
PWM (Enhanced) .................................................... 188
Reads from Flash Program Memory ......................... 99
Resonator Operation ................................................. 35
Table Read Operation ............................................... 95
Table Write Operation ............................................... 96
Table Writes to Flash Program Memory .................. 101
Timer0 in 16-Bit Mode ............................................. 159
Timer0 in 8-Bit Mode ............................................... 158
Timer1 ..................................................................... 161
Timer1 Gate ............................................. 167, 168, 169
Timer2/4/6 ............................................................... 173
Voltage Reference ................................................... 337
Voltage Reference Output Buffer Example ............. 340
Watchdog Timer ...................................................... 360
BN .................................................................................... 376
BNC ................................................................................. 377
BNN ................................................................................. 377
BNOV .............................................................................. 378
BNZ ................................................................................. 378
BOR. See Brown-out Reset.
BOV ................................................................................. 381
BRA ................................................................................. 379
Break Character (12-bit) Transmit and Receive .............. 282
Brown-out Reset (BOR) ..................................................... 62
Detecting ................................................................... 62
Disabling in Sleep Mode ............................................ 62
Minimum Enable Time ............................................... 62
Software Enabled ...................................................... 62
BSF .................................................................................. 379
BTFSC ............................................................................. 380
BTFSS ............................................................................. 380
BTG ................................................................................. 381
BZ .................................................................................... 382
C
C Compilers
MPLAB C18 ............................................................. 418
CALL ................................................................................ 382
Preliminary
DS41412C-page 483
PIC18(L)F2X/4XK22
CALLW ............................................................................. 411
Capture Module. See Enhanced Capture/Compare/PWM
(ECCP)
Capture/Compare/PWM ................................................... 177
Capture/Compare/PWM (CCP)
Associated Registers w/ Capture
.......................................... 179, 180, 183, 187, 201
Associated Registers w/ Compare ........................... 182
Associated Registers w/ PWM ......................... 187, 200
Capture Mode .......................................................... 178
CCPx Pin Configuration ........................................... 178
Compare Mode ........................................................ 181
CCPx Pin Configuration ................................... 181
Software Interrupt Mode .......................... 178, 181
Special Event Trigger ....................................... 182
Timer1 Mode Resource ........................... 178, 181
Prescaler .................................................................. 179
PWM Mode
Duty Cycle ........................................................ 185
Effects of Reset ................................................ 186
Example PWM Frequencies and
Resolutions, 20 MHZ ............................... 186
Example PWM Frequencies and
Resolutions, 32 MHZ ............................... 186
Example PWM Frequencies and
Resolutions, 8 MHz .................................. 186
Operation in Sleep Mode ................................. 186
Resolution ........................................................ 186
System Clock Frequency Changes .................. 186
PWM Operation ....................................................... 184
PWM Overview ........................................................ 184
PWM Period ............................................................. 185
PWM Setup .............................................................. 184
CCPTMRS0 Register ....................................................... 204
CCPTMRS1 Register ....................................................... 204
CCPxCON (ECCPx) Register .......................................... 201
Clock Accuracy with Asynchronous Operation ................ 272
Clock Sources
External Modes .......................................................... 34
EC ...................................................................... 34
HS ...................................................................... 35
LP ....................................................................... 35
OST .................................................................... 34
RC ...................................................................... 36
XT ...................................................................... 35
Internal Modes ........................................................... 36
Frequency Selection .......................................... 38
INTOSC ............................................................. 36
INTOSCIO .......................................................... 36
LFINTOSC ......................................................... 38
Selecting the 31 kHz Source ...................................... 29
Selection Using OSCCON Register ........................... 29
Clock Switching .................................................................. 41
CLRF ................................................................................ 383
CLRWDT .......................................................................... 383
CM1CON0 Register ......................................................... 310
CM2CON0 Register ......................................................... 311
CM2CON1 Register ......................................................... 314
Code Examples
16 x 16 Signed Multiply Routine .............................. 112
16 x 16 Unsigned Multiply Routine .......................... 112
8 x 8 Signed Multiply Routine .................................. 111
8 x 8 Unsigned Multiply Routine .............................. 111
A/D Conversion ........................................................ 297
Capacitance Calibration Routine ............................. 324
DS41412C-page 484
Capacitive Touch Switch Routine ............................ 326
Changing Between Capture Prescalers ................... 179
Clearing RAM Using Indirect Addressing .................. 90
Computed GOTO Using an Offset Value ................... 73
Current Calibration Routine ..................................... 322
Data EEPROM Read ............................................... 107
Data EEPROM Refresh Routine .............................. 108
Data EEPROM Write ............................................... 107
Erasing a Flash Program Memory Row ................... 100
Fast Register Stack ................................................... 73
Initializing PORTA .................................................... 133
Initializing PORTB .................................................... 138
Initializing PORTC ................................................... 142
Initializing PORTD ................................................... 146
Initializing PORTE .................................................... 149
Reading a Flash Program Memory Word .................. 99
Saving Status, WREG and BSR Registers in RAM . 131
Setup for CTMU Calibration Routines ..................... 321
Writing to Flash Program Memory ................... 102–103
Code Protection ............................................................... 349
COMF .............................................................................. 384
Comparator
Associated Registers ............................................... 315
Operation ................................................................. 305
Operation During Sleep ........................................... 309
Response Time ........................................................ 307
Comparator Module
C1 Output State Versus Input Conditions ................ 307
Comparator Specifications ............................................... 439
Comparator Voltage Reference (CVREF)
Effects of a Reset .................................................... 309
Comparator Voltage Reference (CVREF)
Response Time ........................................................ 307
Comparators
C2OUT as T1 Gate .................................................. 164
Effects of a Reset .................................................... 309
Compare Module. See Enhanced Capture/Compare/
PWM (ECCP)
Computed GOTO ............................................................... 73
CONFIG1H Register ........................................................ 351
CONFIG2H Register ........................................................ 353
CONFIG2L Register ........................................................ 352
CONFIG3H Register ........................................................ 354
CONFIG4L Register ........................................................ 355
CONFIG5H Register ........................................................ 356
CONFIG5L Register ........................................................ 355
CONFIG6H Register ........................................................ 357
CONFIG6L Register ........................................................ 356
CONFIG7H Register ........................................................ 358
CONFIG7L Register ........................................................ 357
Configuration Bits ............................................................ 349
Configuration Register Protection .................................... 365
Context Saving During Interrupts ..................................... 131
CPFSEQ .......................................................................... 384
CPFSGT .......................................................................... 385
CPFSLT ........................................................................... 385
CTMU
Associated Registers ............................................... 331
Calibrating ............................................................... 320
Creating a Delay with ............................................... 328
Effects of a Reset .................................................... 329
Initialization .............................................................. 319
Measuring Capacitance with .................................... 325
Measuring Time with ................................................ 327
Operation ................................................................. 318
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
Operation During Idle Mode ..................................... 328
Operation During Sleep Mode ................................. 328
Customer Change Notification Service ............................ 493
Customer Notification Service .......................................... 493
Customer Support ............................................................ 493
CVREF Voltage Reference Specifications ........................ 439
D
Data Addressing Modes ..................................................... 90
Comparing Addressing Modes with the
Extended Instruction Set Enabled ..................... 93
Direct .......................................................................... 90
Indexed Literal Offset ................................................. 92
Instructions Affected .......................................... 92
Indirect ....................................................................... 90
Inherent and Literal .................................................... 90
Data EEPROM
Code Protection ....................................................... 365
Data EEPROM Memory
Associated Registers ............................................... 109
EEADR and EEADRH Registers ............................. 105
EECON1 and EECON2 Registers ........................... 105
Operation During Code-Protect ............................... 108
Protection Against Spurious Write ........................... 108
Reading .................................................................... 107
Using ........................................................................ 108
Write Verify .............................................................. 107
Writing ...................................................................... 107
Data Memory ..................................................................... 76
Access Bank .............................................................. 82
and the Extended Instruction Set ............................... 92
Bank Select Register (BSR) ....................................... 76
General Purpose Registers ........................................ 82
Map for PIC18F/LF23K22 and PIC18F/LF43K22
Devices .............................................................. 77
Map for PIC18F/LF24K22 and PIC18F/LF44K22
Devices .............................................................. 78
Special Function Registers ........................................ 82
DAW ................................................................................. 386
DC and AC Characteristics
Graphs and Tables .................................................. 461
DC Characteristics
Input/Output ............................................................. 436
Power-Down Current ............................................... 424
Primary Idle Supply Current ..................................... 433
Primary Run Supply Current .................................... 431
RC Idle Supply Current ............................................ 429
RC Run Supply Current ........................................... 427
Secondary Oscillator Supply Current ....................... 434
Supply Voltage ......................................................... 423
DCFSNZ .......................................................................... 387
DECF ............................................................................... 386
DECFSZ ........................................................................... 387
Development Support ...................................................... 417
Device Differences ........................................................... 482
Device Overview
Details on Individual Family Members ....................... 14
Features (table) .......................................................... 15
New Core Features .................................................... 13
Other Special Features .............................................. 14
Device Reset Timers .......................................................... 63
PLL Lock Time-out ..................................................... 63
Power-up Timer (PWRT) ........................................... 63
Time-out Sequence .................................................... 63
DEVID1 Register .............................................................. 358
DEVID2 Register .............................................................. 358
 2010 Microchip Technology Inc.
Digital-to-Analog Converter (DAC) .................................. 339
Associated Registers ............................................... 342
Effects of a Reset .................................................... 340
Direct Addressing .............................................................. 91
E
ECCP/CCP. See Enhanced Capture/Compare/PWM
ECCPxAS Register .......................................................... 205
EECON1 Register ...................................................... 97, 106
Effect on Standard PIC Instructions ................................. 414
Effects of Power Managed Modes on Various Clock
Sources ..................................................................... 40
Effects of Reset
PWM mode .............................................................. 186
Electrical Characteristics ................................................. 421
Enhanced Capture/Compare/PWM (ECCP) .................... 177
Enhanced PWM Mode ............................................. 188
Auto-Restart .................................................... 196
Auto-shutdown ................................................ 195
Direction Change in Full-Bridge Output Mode . 194
Full-Bridge Application ..................................... 192
Full-Bridge Mode ............................................. 192
Half-Bridge Application .................................... 191
Half-Bridge Application Examples ................... 197
Half-Bridge Mode ............................................. 191
Output Relationships (Active-High and
Active-Low) .............................................. 189
Output Relationships Diagram ......................... 190
Programmable Dead Band Delay .................... 197
Shoot-through Current ..................................... 197
Start-up Considerations ................................... 199
Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART) ............................. 263
Errata ................................................................................. 12
EUSART .......................................................................... 263
Asynchronous Mode ................................................ 265
12-bit Break Transmit and Receive ................. 282
Associated Registers, Receive ........................ 271
Associated Registers, Transmit ....................... 267
Auto-Wake-up on Break .................................. 280
Baud Rate Generator (BRG) ........................... 275
Clock Accuracy ................................................ 272
Receiver .......................................................... 268
Setting up 9-bit Mode with Address Detect ..... 270
Transmitter ...................................................... 265
Baud Rate Generator (BRG)
Associated Registers ....................................... 276
Auto Baud Rate Detect .................................... 279
Baud Rate Error, Calculating ........................... 275
Baud Rates, Asynchronous Modes ................. 276
Formulas .......................................................... 275
High Baud Rate Select (BRGH Bit) ................. 275
Clock polarity
Synchronous Mode .......................................... 283
Data polarity
Asynchronous Receive .................................... 268
Asynchronous Transmit ................................... 265
Synchronous Mode .......................................... 283
Interrupts
Asychronous Receive ...................................... 269
Asynchronous Receive .................................... 269
Asynchronous Transmit ................................... 265
Synchronous Master Mode .............................. 283, 288
Associated Registers, Receive ........................ 287
Associated Registers, Transmit ............... 284, 289
Reception ........................................................ 286
Preliminary
DS41412C-page 485
PIC18(L)F2X/4XK22
Transmission .................................................... 283
Synchronous Slave Mode
Associated Registers, Receive ........................ 290
Reception ......................................................... 290
Transmission .................................................... 288
Extended Instruction Set
ADDFSR .................................................................. 410
ADDULNK ................................................................ 410
and Using MPLAB Tools .......................................... 416
CALLW ..................................................................... 411
Considerations for Use ............................................ 414
MOVSF .................................................................... 411
MOVSS .................................................................... 412
PUSHL ..................................................................... 412
SUBFSR .................................................................. 413
SUBULNK ................................................................ 413
Syntax ...................................................................... 409
F
Fail-Safe Clock Monitor .............................................. 44, 349
Fail-Safe Condition Clearing ...................................... 44
Fail-Safe Detection .................................................... 44
Fail-Safe Operation .................................................... 44
Reset or Wake-up from Sleep .................................... 44
Fast Register Stack ............................................................ 72
Fixed Voltage Reference (FVR)
Associated Registers ............................................... 338
Flash Program Memory ...................................................... 95
Associated Registers ............................................... 103
Control Registers ....................................................... 96
EECON1 and EECON2 ..................................... 96
TABLAT (Table Latch) Register ......................... 98
TBLPTR (Table Pointer) Register ...................... 98
Erase Sequence ...................................................... 100
Erasing ..................................................................... 100
Operation During Code-Protect ............................... 103
Reading ...................................................................... 99
Table Pointer
Boundaries Based on Operation ........................ 98
Table Pointer Boundaries .......................................... 98
Table Reads and Table Writes .................................. 95
Write Sequence ....................................................... 101
Writing To ................................................................. 101
Protection Against Spurious Writes ................. 103
Unexpected Termination .................................. 103
Write Verify ...................................................... 103
G
GOTO ............................................................................... 388
H
Hardware Multiplier .......................................................... 111
Introduction .............................................................. 111
Operation ................................................................. 111
Performance Comparison ........................................ 111
High/Low-Voltage Detect ................................................. 343
Applications .............................................................. 346
Associated Registers ............................................... 347
Characteristics ......................................................... 440
Current Consumption ............................................... 345
Effects of a Reset ..................................................... 347
Operation ................................................................. 344
During Sleep .................................................... 347
Setup ........................................................................ 345
Start-up Time ........................................................... 345
Typical Low-Voltage Detect Application ................... 346
DS41412C-page 486
HLVD. See High/Low-Voltage Detect. ............................. 343
I
I2C Mode (MSSPx)
Acknowledge Sequence Timing .............................. 246
Bus Collision
During a Repeated Start Condition .................. 251
During a Stop Condition .................................. 252
Effects of a Reset .................................................... 247
I2C Clock Rate w/BRG ............................................. 254
Master Mode
Operation ......................................................... 238
Reception ........................................................ 244
Start Condition Timing ............................. 240, 241
Transmission ................................................... 242
Multi-Master Communication, Bus Collision and
Arbitration ........................................................ 248
Multi-Master Mode ................................................... 247
Read/Write Bit Information (R/W Bit) ....................... 223
Slave Mode
Transmission ................................................... 228
Sleep Operation ....................................................... 247
Stop Condition Timing ............................................. 246
ID Locations ............................................................. 349, 365
INCF ................................................................................ 388
INCFSZ ............................................................................ 389
In-Circuit Debugger .......................................................... 365
In-Circuit Serial Programming (ICSP) ...................... 349, 365
Indexed Literal Offset Addressing
and Standard PIC18 Instructions ............................. 414
Indexed Literal Offset Mode ............................................. 414
Indirect Addressing ............................................................ 91
INFSNZ ............................................................................ 389
Instruction Cycle ................................................................ 74
Clocking Scheme ....................................................... 74
Instruction Flow/Pipelining ................................................. 74
Instruction Set .................................................................. 367
ADDLW .................................................................... 373
ADDWF .................................................................... 373
ADDWF (Indexed Literal Offset Mode) .................... 415
ADDWFC ................................................................. 374
ANDLW .................................................................... 374
ANDWF .................................................................... 375
BC ............................................................................ 375
BCF ......................................................................... 376
BN ............................................................................ 376
BNC ......................................................................... 377
BNN ......................................................................... 377
BNOV ...................................................................... 378
BNZ ......................................................................... 378
BOV ......................................................................... 381
BRA ......................................................................... 379
BSF .......................................................................... 379
BSF (Indexed Literal Offset Mode) .......................... 415
BTFSC ..................................................................... 380
BTFSS ..................................................................... 380
BTG ......................................................................... 381
BZ ............................................................................ 382
CALL ........................................................................ 382
CLRF ....................................................................... 383
CLRWDT ................................................................. 383
COMF ...................................................................... 384
CPFSEQ .................................................................. 384
CPFSGT .................................................................. 385
CPFSLT ................................................................... 385
DAW ........................................................................ 386
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
DCFSNZ .................................................................. 387
DECF ....................................................................... 386
DECFSZ ................................................................... 387
Extended Instruction Set .......................................... 409
General Format ........................................................ 369
GOTO ...................................................................... 388
INCF ......................................................................... 388
INCFSZ .................................................................... 389
INFSNZ .................................................................... 389
IORLW ..................................................................... 390
IORWF ..................................................................... 390
LFSR ........................................................................ 391
MOVF ....................................................................... 391
MOVFF .................................................................... 392
MOVLB .................................................................... 392
MOVLW ................................................................... 393
MOVWF ................................................................... 393
MULLW .................................................................... 394
MULWF .................................................................... 394
NEGF ....................................................................... 395
NOP ......................................................................... 395
Opcode Field Descriptions ....................................... 368
POP ......................................................................... 396
PUSH ....................................................................... 396
RCALL ..................................................................... 397
RESET ..................................................................... 397
RETFIE .................................................................... 398
RETLW .................................................................... 398
RETURN .................................................................. 399
RLCF ........................................................................ 399
RLNCF ..................................................................... 400
RRCF ....................................................................... 400
RRNCF .................................................................... 401
SETF ........................................................................ 401
SETF (Indexed Literal Offset Mode) ........................ 415
SLEEP ..................................................................... 402
SUBFWB .................................................................. 402
SUBLW .................................................................... 403
SUBWF .................................................................... 403
SUBWFB .................................................................. 404
SWAPF .................................................................... 404
TBLRD ..................................................................... 405
TBLWT ..................................................................... 406
TSTFSZ ................................................................... 407
XORLW .................................................................... 407
XORWF .................................................................... 408
INTCON Register ............................................................. 115
INTCON Registers ................................................... 115–117
INTCON2 Register ........................................................... 116
INTCON3 Register ........................................................... 117
Internal Oscillator Block
HFINTOSC Frequency Drift ....................................... 38
PLL in HFINTOSC Modes .......................................... 39
Internal RC Oscillator
Use with WDT .......................................................... 360
Internal Sampling Switch (RSS) IMPEDANCE ..................... 302
Internet Address ............................................................... 493
Interrupt Sources ............................................................. 349
ADC ......................................................................... 293
Interrupt-on-Change (RB7:RB4) .............................. 138
INTn Pin ................................................................... 131
PORTB, Interrupt-on-Change .................................. 131
TMR0 ....................................................................... 131
TMR0 Overflow ........................................................ 159
Interrupts
TMR1 ....................................................................... 166
 2010 Microchip Technology Inc.
IORLW ............................................................................. 390
IORWF ............................................................................. 390
IPR Registers ................................................................... 127
IPR1 Register .................................................................. 127
IPR2 Register .................................................................. 128
IPR3 Register .................................................................. 129
IPR4 Register .................................................................. 130
IPR5 Register .................................................................. 130
L
LFSR ............................................................................... 391
Low-Voltage ICSP Programming. See Single-Supply
ICSP Programming
M
Map .............................................................................. 79, 80
Master Clear (MCLR) ......................................................... 61
Master Synchronous Serial Port. See MSSPx
Memory Organization
Data Memory ............................................................. 76
Program Memory ....................................................... 69
Microchip Internet Web Site ............................................. 493
MOVF .............................................................................. 391
MOVFF ............................................................................ 392
MOVLB ............................................................................ 392
MOVLW ........................................................................... 393
MOVSF ............................................................................ 411
MOVSS ............................................................................ 412
MOVWF ........................................................................... 393
MPLAB ASM30 Assembler, Linker, Librarian .................. 418
MPLAB Integrated Development Environment Software . 417
MPLAB PM3 Device Programmer ................................... 420
MPLAB REAL ICE In-Circuit Emulator System ............... 419
MPLINK Object Linker/MPLIB Object Librarian ............... 418
MSSPx ............................................................................. 207
SPI Mode ................................................................. 210
SSPxBUF Register .................................................. 213
SSPxSR Register .................................................... 213
MULLW ............................................................................ 394
MULWF ............................................................................ 394
N
NEGF ............................................................................... 395
NOP ................................................................................. 395
O
OSCCON Register ....................................................... 32, 33
Oscillator Configuration
EC .............................................................................. 27
ECIO .......................................................................... 27
HS .............................................................................. 27
HSPLL ....................................................................... 27
LP .............................................................................. 27
RC ............................................................................. 27
XT .............................................................................. 27
Oscillator Selection .......................................................... 349
Oscillator Start-up Timer (OST) ................................... 40, 63
Oscillator Switching
Fail-Safe Clock Monitor ............................................. 44
Two-Speed Clock Start-up ........................................ 42
OSCTUNE Register ........................................................... 37
P
P1A/P1B/P1C/P1D.See Enhanced Capture/Compare/
PWM (ECCP) .......................................................... 188
Packaging Information ..................................................... 463
Preliminary
DS41412C-page 487
PIC18(L)F2X/4XK22
Marking .................................................................... 463
PIE Registers ................................................................... 123
PIE1 Register ................................................................... 123
PIE2 Register ................................................................... 124
PIE3 Register3 ................................................................. 125
PIE4 Register ................................................................... 126
PIE5 Register ................................................................... 126
PIR Registers ................................................................... 118
PIR1 Register ................................................................... 118
PIR2 Register ................................................................... 119
PLL Frequency Multiplier ................................................... 39
POP .................................................................................. 396
POR. See Power-on Reset.
PORTA
Associated Registers ............................................... 135
PORTA Register ...................................................... 133
TRISA Register ........................................................ 133
PORTB
Associated Registers ............................................... 141
PORTB Register ...................................................... 138
PORTC
Associated Registers ............................................... 145
PORTC Register ...................................................... 142
PORTD
Associated Registers ............................................... 149
PORTD Register ...................................................... 146
TRISD Register ........................................................ 146
PORTE
Associated Registers ............................................... 150
PORTE Register ...................................................... 149
Power Managed Modes ..................................................... 47
and A/D Operation ................................................... 296
Effects on Clock Sources ........................................... 40
Entering ...................................................................... 47
Exiting Idle and Sleep Modes .................................... 54
by Interrupt ......................................................... 54
by Reset ............................................................. 54
by WDT Time-out ............................................... 54
Without a Start-up Delay .................................... 54
Idle Modes ................................................................. 51
PRI_IDLE ........................................................... 52
RC_IDLE ............................................................ 53
SEC_IDLE .......................................................... 52
Multiple Sleep Functions ............................................ 48
Run Modes ................................................................. 48
PRI_RUN ........................................................... 48
SEC_RUN .......................................................... 48
Selecting .................................................................... 47
Sleep Mode ................................................................ 51
Summary (table) ........................................................ 47
Power-on Reset (POR) ...................................................... 61
Power-up Timer (PWRT) ........................................... 63
Time-out Sequence .................................................... 63
Power-up Delays ................................................................ 40
Power-up Timer (PWRT) .................................................... 40
Prescaler, Timer0 ............................................................. 159
PRI_IDLE Mode ................................................................. 52
PRI_RUN Mode ................................................................. 48
Program Counter ................................................................ 70
PCL, PCH and PCU Registers ................................... 70
PCLATH and PCLATU Registers .............................. 70
Program Memory
and Extended Instruction Set ..................................... 94
Code Protection ....................................................... 363
Instructions ................................................................. 75
DS41412C-page 488
Two-Word .......................................................... 75
Interrupt Vector .......................................................... 69
Look-up Tables .......................................................... 73
Map and Stack (diagram) .......................................... 70
Reset Vector .............................................................. 69
Program Verification and Code Protection ...................... 362
Associated Registers ............................................... 362
PSTRxCON Register ....................................................... 206
PUSH ............................................................................... 396
PUSH and POP Instructions .............................................. 72
PUSHL ............................................................................. 412
PWM (ECCP Module)
PWM Steering .......................................................... 198
Steering Synchronization ......................................... 198
PWM Mode. See Enhanced Capture/Compare/PWM ..... 188
PWM Steering .................................................................. 198
PWMxCON Register ........................................................ 206
R
RAM. See Data Memory.
RC_IDLE Mode .................................................................. 53
RC_RUN ............................................................................ 48
RCALL ............................................................................. 397
RCON Register .................................................................. 60
Bit Status During Initialization .................................... 67
RCREG ............................................................................ 270
RCSTA Register .............................................................. 273
Reader Response ............................................................ 494
Register
RCREG Register ..................................................... 279
Register File ....................................................................... 82
Registers
ADCON0 (ADC Control 0) ....................................... 298
ADCON1 (ADC Control 1) ....................................... 299
ADCON2 (ADC Control 2) ....................................... 300
ADRESH (ADC Result High) with ADFM = 0) ......... 301
ADRESH (ADC Result High) with ADFM = 1) ......... 301
ADRESL (ADC Result Low) with ADFM = 0) ........... 301
ADRESL (ADC Result Low) with ADFM = 1) ........... 301
BAUDCON (Baud Rate Control) .............................. 274
BAUDCON (EUSART Baud Rate Control) .............. 274
CCPTMRS0 (PWM Timer Selection Control 0) ....... 204
CCPTMRS1 (PWM Timer Selection Control 1) ....... 204
CCPxCON (ECCPx Control) .................................... 201
CM1CON0 (C1 Control) ........................................... 310
CM2CON0 (C2 Control) ........................................... 311
CM2CON1 (C2 Control) ........................................... 314
CONFIG1H (Configuration 1 High) .......................... 351
CONFIG2H (Configuration 2 High) .......................... 353
CONFIG2L (Configuration 2 Low) ........................... 352
CONFIG3H (Configuration 3 High) .......................... 354
CONFIG4L (Configuration 4 Low) ........................... 355
CONFIG5H (Configuration 5 High) .......................... 356
CONFIG5L (Configuration 5 Low) ........................... 355
CONFIG6H (Configuration 6 High) .......................... 357
CONFIG6L (Configuration 6 Low) ........................... 356
CONFIG7H (Configuration 7 High) .......................... 358
CONFIG7L (Configuration 7 Low) ........................... 357
CTMUCONH (CTMU Control High) ......................... 329
CTMUCONL (CTMU Control Low) .......................... 330
CTMUICON (CTMU Current Control) ...................... 331
DEVID1 (Device ID 1) .............................................. 358
DEVID2 (Device ID 2) .............................................. 358
ECCPxAS (CCPx Auto-Shutdown Control) ............. 205
EECON1 (Data EEPROM Control 1) ................. 97, 106
HLVDCON (High/Low-Voltage Detect Control) ....... 343
Preliminary
 2010 Microchip Technology Inc.
PIC18(L)F2X/4XK22
INTCON (Interrupt Control) ...................................... 115
INTCON2 (Interrupt Control 2) ................................. 116
INTCON3 (Interrupt Control 3) ................................. 117
IPR1 (Peripheral Interrupt Priority 1) ........................ 127
IPR2 (Peripheral Interrupt Priority 2) ........................ 128
IPR3 (Peripheral Interrupt Priority) ........................... 129
IPR4 (Peripheral Interrupt Priority) ........................... 130
IPR5 (Peripheral Interrupt Priority) ........................... 130
OSCCON (Oscillator Control) .............................. 32, 33
OSCTUNE (Oscillator Tuning) ................................... 37
PIE1 (Peripheral Interrupt Enable 1) ........................ 123
PIE2 (Peripheral Interrupt Enable 2) ........................ 124
PIE3 (Peripheral Interrupt Enable] ........................... 125
PIE4 (Peripheral Interrupt Enable) ........................... 126
PIE5 (Peripheral Interrupt Enable) ........................... 126
PIR1 (Peripheral Interrupt Request 1) ..................... 118
PIR2 (Peripheral Interrupt Request 2) ..................... 119
PSTRxCON (PWM Steering Control) ...................... 206
PWMxCON (Enhanced PWM Control) .................... 206
RCON (Reset Control) ....................................... 60, 130
RCSTA (Receive Status and Control) ...................... 273
SLRCON (PORT Slew Rate Control) ....................... 156
SRCON0 (SR Latch Control 0) ................................ 335
SRCON1 (SR Latch Control 1) ................................ 336
SSPxADD (MSSPx Address and Baud Rate,
I2C Mode) ........................................................ 261
SSPxCON1 (MSSPx Control 1) ............................... 256
SSPxCON2 (SSPx Control 2) .................................. 258
SSPxMSK (SSPx Mask) .......................................... 260
SSPxSTAT (SSPx Status) ....................................... 255
STATUS ..................................................................... 89
STKPTR (Stack Pointer) ............................................ 72
T0CON (Timer0 Control) .......................................... 157
T1CON (Timer1 Control) .......................................... 170
T1GCON (Timer1 Gate Control) .............................. 171
TXCON .................................................................... 175
TXSTA (Transmit Status and Control) ..................... 272
VREFCON0 ............................................................. 338
VREFCON1 ............................................................. 341
VREFCON2 ............................................................. 342
WDTCON (Watchdog Timer Control) ...................... 361
RESET ............................................................................. 397
Reset State of Registers .................................................... 67
Resets .............................................................................. 349
Brown-out Reset (BOR) ........................................... 349
Oscillator Start-up Timer (OST) ............................... 349
Power-on Reset (POR) ............................................ 349
Power-up Timer (PWRT) ......................................... 349
RETFIE ............................................................................ 398
RETLW ............................................................................ 398
RETURN .......................................................................... 399
Return Address Stack ........................................................ 70
Return Stack Pointer (STKPTR) ........................................ 71
Revision History ............................................................... 481
RLCF ................................................................................ 399
RLNCF ............................................................................. 400
RRCF ............................................................................... 400
RRNCF ............................................................................ 401
S
SEC_IDLE Mode ................................................................ 52
SEC_RUN Mode ................................................................ 48
SETF ................................................................................ 401
Shoot-through Current ..................................................... 197
Single-Supply ICSP Programming.
SLEEP ............................................................................. 402
 2010 Microchip Technology Inc.
Sleep
OSC1 and OSC2 Pin States ...................................... 41
Sleep Mode ....................................................................... 51
Slew Rate ........................................................................ 151
SLRCON Register ........................................................... 156
Software Simulator (MPLAB SIM) ................................... 419
SPBRG ............................................................................ 275
SPBRGH ......................................................................... 275
Special Event Trigger ...................................................... 296
Special Function Registers ................................................ 82
Map ............................................................................ 83
SPI Mode (MSSPx)
Associated Registers ............................................... 217
SPI Clock ................................................................. 213
SR Latch
Associated Registers ............................................... 336
Effects of a Reset .................................................... 333
SRCON0 Register ........................................................... 335
SRCON1 Register ........................................................... 336
SSPxADD Register .......................................................... 261
SSPxCON1 Register ....................................................... 256
SSPxCON2 Register ....................................................... 258
SSPxMSK Register .......................................................... 260
SSPxOV .......................................................................... 244
SSPxOV Status Flag ....................................................... 244
SSPxSTAT Register ........................................................ 255
R/W Bit .................................................................... 223
Stack Full/Underflow Resets .............................................. 72
Standard Instructions ....................................................... 367
STATUS Register .............................................................. 89
STKPTR Register .............................................................. 72
SUBFSR .......................................................................... 413
SUBFWB ......................................................................... 402
SUBLW ............................................................................ 403
SUBULNK ........................................................................ 413
SUBWF ............................................................................ 403
SUBWFB ......................................................................... 404
SWAPF ............................................................................ 404
T
T0CON Register .............................................................. 157
T1CON Register .............................................................. 170
T1GCON Register ........................................................... 171
Table Pointer Operations (table) ........................................ 98
Table Reads/Table Writes ................................................. 73
TBLRD ............................................................................. 405
TBLWT ............................................................................ 406
Time-out in Various Situations (table) ................................ 64
Timer0 ............................................................................. 157
Associated Registers ............................................... 159
Operation ................................................................. 158
Overflow Interrupt .................................................... 159
Prescaler ................................................................. 159
Prescaler Assignment (PSA Bit) .............................. 159
Prescaler Select (T0PS2:T0PS0 Bits) ..................... 159
Prescaler. See Prescaler, Timer0.
Reads and Writes in 16-Bit Mode ............................ 158
Source Edge Select (T0SE Bit) ............................... 158
Source Select (T0CS Bit) ........................................ 158
Switching Prescaler Assignment ............................. 159
Timer1 ............................................................................. 161
Associated registers ................................................ 172
Asynchronous Counter Mode .................................. 163
Reading and Writing ........................................ 163
Clock Source Selection ........................................... 162
Interrupt ................................................................... 166
Preliminary
DS41412C-page 489
PIC18(L)F2X/4XK22
Operation ................................................................. 162
Operation During Sleep ........................................... 166
Oscillator .................................................................. 163
Prescaler .................................................................. 163
Timer1 Gate
Selecting Source .............................................. 164
TMR1H Register ...................................................... 161
TMR1L Register ....................................................... 161
Timer2
Associated registers ................................................. 176
Timer2/4/6 ........................................................................ 173
Associated registers ................................................. 176
Timers
Timer1
T1CON ............................................................. 170
T1GCON .......................................................... 171
Timer2/4/6
TXCON ............................................................ 175
Timing Diagrams
A/D Conversion ........................................................ 459
Acknowledge Sequence .......................................... 246
Asynchronous Reception ......................................... 271
Asynchronous Transmission .................................... 266
Asynchronous Transmission (Back to Back) ........... 267
Auto Wake-up Bit (WUE) During Normal Operation 281
Auto Wake-up Bit (WUE) During Sleep ................... 281
Automatic Baud Rate Calculator .............................. 280
Baud Rate Generator with Clock Arbitration ............ 239
BRG Reset Due to SDA Arbitration During Start
Condition .......................................................... 250
Brown-out Reset (BOR) ........................................... 446
Bus Collision During a Repeated Start Condition
(Case 1) ........................................................... 251
Bus Collision During a Repeated Start Condition
(Case 2) ........................................................... 251
Bus Collision During a Start Condition (SCL = 0) .... 250
Bus Collision During a Stop Condition (Case 1) ...... 252
Bus Collision During a Stop Condition (Case 2) ...... 252
Bus Collision During Start Condition (SDA only) ..... 249
Bus Collision for Transmit and Acknowledge ........... 248
Capture/Compare/PWM (CCP) ................................ 448
CLKO and I/O .......................................................... 445
Clock Synchronization ............................................. 236
Clock/Instruction Cycle .............................................. 74
Comparator Output .................................................. 305
EUSART Synchronous Receive (Master/Slave) ...... 458
EUSART Synchronous Transmission
(Master/Slave) .................................................. 458
Example SPI Master Mode (CKE = 0) ..................... 449
Example SPI Master Mode (CKE = 1) ....