MICROCHIP PIC16F886T-E/SS

PIC16F882/883/884/886/887
Data Sheet
28/40/44-Pin, Enhanced Flash-Based 8-Bit
CMOS Microcontrollers with
nanoWatt Technology
© 2009 Microchip Technology Inc.
DS41291F
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and may be superseded by updates.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, Accuron,
dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro,
PICSTART, rfPIC, SmartShunt and UNI/O are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
FilterLab, Linear Active Thermistor, MXDEV, MXLAB,
SEEVAL, SmartSensor and The Embedded Control Solutions
Company are registered trademarks of Microchip Technology
Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, In-Circuit Serial
Programming, ICSP, ICEPIC, Mindi, MiWi, MPASM, MPLAB
Certified logo, MPLIB, MPLINK, mTouch, nanoWatt XLP,
PICkit, PICDEM, PICDEM.net, PICtail, PIC32 logo, PowerCal,
PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB, Select
Mode, Total Endurance, TSHARC, WiperLock and ZENA are
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2009, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS41291F-page ii
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
28/40/44-Pin Flash-Based, 8-Bit CMOS Microcontrollers with
nanoWatt Technology
High-Performance RISC CPU:
Peripheral Features:
• Only 35 Instructions to Learn:
- All single-cycle instructions except branches
• Operating Speed:
- DC – 20 MHz oscillator/clock input
- DC – 200 ns instruction cycle
• Interrupt Capability
• 8-Level Deep Hardware Stack
• Direct, Indirect and Relative Addressing modes
• 24/35 I/O Pins with Individual Direction Control:
- High current source/sink for direct LED drive
- Interrupt-on-Change pin
- Individually programmable weak pull-ups
- Ultra Low-Power Wake-up (ULPWU)
• Analog Comparator Module with:
- Two analog comparators
- Programmable on-chip voltage reference
(CVREF) module (% of VDD)
- Fixed voltage reference (0.6V)
- Comparator inputs and outputs externally
accessible
- SR Latch mode
- External Timer1 Gate (count enable)
• A/D Converter:
- 10-bit resolution and 11/14 channels
• Timer0: 8-bit Timer/Counter with 8-bit
Programmable Prescaler
• Enhanced Timer1:
- 16-bit timer/counter with prescaler
- External Gate Input mode
- Dedicated low-power 32 kHz oscillator
• Timer2: 8-bit Timer/Counter with 8-bit Period
Register, Prescaler and Postscaler
• Enhanced Capture, Compare, PWM+ Module:
- 16-bit Capture, max. resolution 12.5 ns
- Compare, max. resolution 200 ns
- 10-bit PWM with 1, 2 or 4 output channels,
programmable “dead time”, max. frequency
20 kHz
- PWM output steering control
• Capture, Compare, PWM Module:
- 16-bit Capture, max. resolution 12.5 ns
- 16-bit Compare, max. resolution 200 ns
- 10-bit PWM, max. frequency 20 kHz
• Enhanced USART Module:
- Supports RS-485, RS-232, and LIN 2.0
- Auto-Baud Detect
- Auto-Wake-Up on Start bit
• In-Circuit Serial ProgrammingTM (ICSPTM) via Two
Pins
• Master Synchronous Serial Port (MSSP) Module
supporting 3-wire SPI (all 4 modes) and I2C™
Master and Slave Modes with I2C Address Mask
Special Microcontroller Features:
• Precision Internal Oscillator:
- Factory calibrated to ±1%
- Software selectable frequency range of
8 MHz to 31 kHz
- Software tunable
- Two-Speed Start-up mode
- Crystal fail detect for critical applications
- Clock mode switching during operation for
power savings
• Power-Saving Sleep mode
• Wide Operating Voltage Range (2.0V-5.5V)
• Industrial and Extended Temperature Range
• Power-on Reset (POR)
• Power-up Timer (PWRT) and Oscillator Start-up
Timer (OST)
• Brown-out Reset (BOR) with Software Control
Option
• Enhanced Low-Current Watchdog Timer (WDT)
with On-Chip Oscillator (software selectable
nominal 268 seconds with full prescaler) with
software enable
• Multiplexed Master Clear with Pull-up/Input Pin
• Programmable Code Protection
• High Endurance Flash/EEPROM Cell:
- 100,000 write Flash endurance
- 1,000,000 write EEPROM endurance
- Flash/Data EEPROM retention: > 40 years
• Program Memory Read/Write during run time
• In-Circuit Debugger (on board)
Low-Power Features:
• Standby Current:
- 50 nA @ 2.0V, typical
• Operating Current:
- 11 μA @ 32 kHz, 2.0V, typical
- 220 μA @ 4 MHz, 2.0V, typical
• Watchdog Timer Current:
- 1 μA @ 2.0V, typical
© 2009 Microchip Technology Inc.
DS41291F-page 1
PIC16F882/883/884/886/887
Device
Program
Memory
Data Memory
I/O
10-bit A/D
(ch)
ECCP/
CCP
EUSART
MSSP
Comparators
Timers
8/16-bit
128
24
11
1/1
1
1
2
2/1
256
24
11
1/1
1
1
2
2/1
256
256
35
14
1/1
1
1
2
2/1
8192
368
256
24
11
1/1
1
1
2
2/1
8192
368
256
35
14
1/1
1
1
2
2/1
Flash
(words)
SRAM
(bytes)
EEPROM
(bytes)
PIC16F882
2048
128
PIC16F883
4096
256
PIC16F884
4096
PIC16F886
PIC16F887
DS41291F-page 2
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
Pin Diagrams – PIC16F882/883/886, 28-Pin PDIP, SOIC, SSOP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
RE3/MCLR/VPP
RA0/AN0/ULPWU/C12IN0RA1/AN1/C12IN1RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3/VREF+/C1IN+
RA4/T0CKI/C1OUT
RA5/AN4/SS/C2OUT
VSS
RA7/OSC1/CLKIN
RA6/OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/P1A/CCP1
RC3/SCK/SCL
TABLE 1:
PIC16F882/883/886
28-pin PDIP, SOIC, SSOP
28
27
26
25
24
23
22
21
20
19
18
17
16
15
RB7/ICSPDAT
RB6/ICSPCLK
RB5/AN13/T1G
RB4/AN11/P1D
RB3/AN9/PGM/C12IN2RB2/AN8/P1B
RB1/AN10/P1C/C12IN3RB0/AN12/INT
VDD
VSS
RC7/RX/DT
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
PIC16F882/883/886 28-PIN SUMMARY (PDIP, SOIC, SSOP)
I/O
Pin
Analog
Comparators
Timers
ECCP
EUSART
MSSP
Interrupt Pull-up
Basic
RA0
2
AN0/ULPWU
C12IN0-
—
—
—
—
—
—
—
RA1
3
AN1
C12IN1-
—
—
—
—
—
—
—
RA2
4
AN2
C2IN+
—
—
—
—
—
—
VREF-/CVREF
RA3
5
AN3
C1IN+
—
—
—
—
—
—
VREF+
RA4
6
—
C1OUT
T0CKI
—
—
—
—
—
—
RA5
7
AN4
C2OUT
—
—
—
SS
—
—
—
RA6
10
—
—
—
—
—
—
—
—
OSC2/CLKOUT
OSC1/CLKIN
RA7
9
—
—
—
—
—
—
—
—
RB0
21
AN12
—
—
—
—
—
IOC/INT
Y
—
RB1
22
AN10
C12IN3-
—
P1C
—
—
IOC
Y
—
RB2
23
AN8
—
—
P1B
—
—
IOC
Y
—
RB3
24
AN9
C12IN2-
—
—
—
—
IOC
Y
PGM
RB4
25
AN11
—
—
P1D
—
—
IOC
Y
—
RB5
26
AN13
—
T1G
—
—
—
IOC
Y
—
RB6
27
—
—
—
—
—
—
IOC
Y
ICSPCLK
RB7
28
—
—
—
—
—
—
IOC
Y
ICSPDAT
RC0
11
—
—
T1OSO/T1CKI
—
—
—
—
—
—
RC1
12
—
—
T1OSI
CCP2
—
—
—
—
—
RC2
13
—
—
—
CCP1/P1A
—
—
—
—
—
—
RC3
14
—
—
—
—
—
SCK/SCL
—
—
RC4
15
—
—
—
—
—
SDI/SDA
—
—
—
RC5
16
—
—
—
—
—
SDO
—
—
—
RC6
17
—
—
—
—
TX/CK
—
—
—
—
RC7
18
—
—
—
—
RX/DT
—
—
—
—
RE3
1
—
—
—
—
—
—
—
Y(1)
MCLR/VPP
—
20
—
—
—
—
—
—
—
—
VDD
—
8
—
—
—
—
—
—
—
—
VSS
—
19
—
—
—
—
—
—
—
—
VSS
Note 1:
Pull-up activated only with external MCLR configuration.
© 2009 Microchip Technology Inc.
DS41291F-page 3
PIC16F882/883/884/886/887
Pin Diagrams – PIC16F882/883/886, 28-Pin QFN
28
27
26
25
24
23
22
RA1/AN1/C12IN1RA0/AN0/ULPWU/C12IN0RE3/MCLR/VPP
RB7/ICSPDAT
RB6/ICSPCLK
RB5/AN13/T1G
RB4/AN11/P1D
28-pin QFN
8
9
10
11
12
13
14
1
21
2
20
3
19
4 PIC16F882/883/886 18
5
17
6
16
15
7
RB3/AN9/PGM/C12IN2RB2/AN8/P1B
RB1/AN10/P1C/C12IN3RB0/AN12/INT
VDD
VSS
RC7/RX/DT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/P1A/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3/VREF+/C1IN+
RA4/T0CKI/C1OUT
RA5/AN4/SS/C2OUT
VSS
RA7/OSC1/CLKIN
RA6/OSC2/CLKOUT
DS41291F-page 4
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 2:
PIC16F882/883/886 28-PIN SUMMARY (QFN)
I/O
Pin
Analog
Comparators
Timers
ECCP
EUSART
MSSP
Interrupt Pull-up
Basic
RA0
27
AN0/ULPWU
C12IN0-
—
—
—
—
—
—
—
RA1
28
AN1
C12IN1-
—
—
—
—
—
—
—
RA2
1
AN2
C2IN+
—
—
—
—
—
—
VREF-/CVREF
RA3
2
AN3
C1IN+
—
—
—
—
—
—
VREF+
—
RA4
3
—
C1OUT
T0CKI
—
—
—
—
—
RA5
4
AN4
C2OUT
—
—
—
SS
—
—
—
RA6
7
—
—
—
—
—
—
—
—
OSC2/CLKOUT
RA7
6
—
—
—
—
—
—
—
—
OSC1/CLKIN
RB0
18
AN12
—
—
—
—
—
IOC/INT
Y
—
RB1
19
AN10
C12IN3-
—
P1C
—
—
IOC
Y
—
RB2
20
AN8
—
—
P1B
—
—
IOC
Y
—
RB3
21
AN9
C12IN2-
—
—
—
—
IOC
Y
PGM
—
RB4
22
AN11
—
—
P1D
—
—
IOC
Y
RB5
23
AN13
—
T1G
—
—
—
IOC
Y
—
RB6
24
—
—
—
—
—
—
IOC
Y
ICSPCLK
RB7
25
—
—
—
—
—
—
IOC
Y
ICSPDAT
RC0
8
—
—
T1OSO/T1CKI
—
—
—
—
—
—
RC1
9
—
—
T1OSI
CCP2
—
—
—
—
—
RC2
10
—
—
—
CCP1/P1A
—
—
—
—
—
RC3
11
—
—
—
—
—
SCK/SCL
—
—
—
RC4
12
—
—
—
—
—
SDI/SDA
—
—
—
RC5
13
—
—
—
—
—
SDO
—
—
—
RC6
14
—
—
—
—
TX/CK
—
—
—
—
RC7
15
—
—
—
—
RX/DT
—
—
—
—
RE3
26
—
—
—
—
—
—
—
Y(1)
MCLR/VPP
—
17
—
—
—
—
—
—
—
—
VDD
—
5
—
—
—
—
—
—
—
—
VSS
—
16
—
—
—
—
—
—
—
—
VSS
Note 1:
Pull-up activated only with external MCLR configuration.
© 2009 Microchip Technology Inc.
DS41291F-page 5
PIC16F882/883/884/886/887
Pin Diagrams – PIC16F884/887, 40-Pin PDIP
RE3/MCLR/VPP
RA0/AN0/ULPWU/C12IN0RA1/AN1/C12IN1RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3/VREF+/C1IN+
RA4/T0CKI/C1OUT
RA5/AN4/SS/C2OUT
RE0/AN5
RE1/AN6
RE2/AN7
VDD
VSS
RA7/OSC1/CLKIN
RA6/OSC2/CLKOUT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/P1A/CCP1
RC3/SCK/SCL
RD0
RD1
DS41291F-page 6
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PIC16F884/887
40-pin PDIP
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
RB7/ICSPDAT
RB6/ICSPCLK
RB5/AN13/T1G
RB4/AN11
RB3/AN9/PGM/C12IN2RB2/AN8
RB1/AN10/C12IN3RB0/AN12/INT
VDD
VSS
RD7/P1D
RD6/P1C
RD5/P1B
RD4
RC7/RX/DT
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3
RD2
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 3:
PIC16F884/887 40-PIN SUMMARY (PDIP)
I/O
Pin
Analog
Comparators
Timers
ECCP
EUSART
MSSP
RA0
2
AN0/ULPWU
C12IN0-
—
—
—
—
Interrupt Pull-up
—
—
Basic
RA1
3
AN1
C12IN1-
—
—
—
—
—
—
—
RA2
4
AN2
C2IN+
—
—
—
—
—
—
VREF-/CVREF
RA3
5
AN3
C1IN+
—
—
—
—
—
—
VREF+
RA4
6
—
C1OUT
T0CKI
—
—
—
—
—
—
RA5
7
AN4
C2OUT
—
—
—
SS
—
—
—
RA6
14
—
—
—
—
—
—
—
—
OSC2/CLKOUT
—
RA7
13
—
—
—
—
—
—
—
—
OSC1/CLKIN
RB0
33
AN12
—
—
—
—
—
IOC/INT
Y
—
RB1
34
AN10
C12IN3-
—
—
—
—
IOC
Y
—
RB2
35
AN8
—
—
—
—
—
IOC
Y
—
RB3
36
AN9
C12IN2-
—
—
—
—
IOC
Y
PGM
RB4
37
AN11
—
—
—
—
—
IOC
Y
—
RB5
38
AN13
—
T1G
—
—
—
IOC
Y
—
RB6
39
—
—
—
—
—
—
IOC
Y
ICSPCLK
RB7
40
—
—
—
—
—
—
IOC
Y
ICSPDAT
RC0
15
—
—
T1OSO/T1CKI
—
—
—
—
—
—
RC1
16
—
—
T1OSI
CCP2
—
—
—
—
—
RC2
17
—
—
—
CCP1/P1A
—
—
—
—
—
RC3
18
—
—
—
—
—
SCK/SCL
—
—
—
RC4
23
—
—
—
—
—
SDI/SDA
—
—
—
—
RC5
24
—
—
—
—
—
SDO
—
—
RC6
25
—
—
—
—
TX/CK
—
—
—
—
RC7
26
—
—
—
—
RX/DT
—
—
—
—
RD0
19
—
—
—
—
—
—
—
—
—
—
RD1
20
—
—
—
—
—
—
—
—
RD2
21
—
—
—
—
—
—
—
—
—
RD3
22
—
—
—
—
—
—
—
—
—
RD4
27
—
—
—
—
—
—
—
—
—
—
RD5
28
—
—
—
P1B
—
—
—
—
RD6
29
—
—
—
P1C
—
—
—
—
—
RD7
30
—
—
—
P1D
—
—
—
—
—
RE0
8
AN5
—
—
—
—
—
—
—
—
RE1
9
AN6
—
—
—
—
—
—
—
—
RE2
10
AN7
—
—
—
—
—
—
—
—
RE3
1
—
—
—
—
—
—
—
Y(1)
MCLR/VPP
—
11
—
—
—
—
—
—
—
—
VDD
—
32
—
—
—
—
—
—
—
—
VDD
—
12
—
—
—
—
—
—
—
—
VSS
—
31
—
—
—
—
—
—
—
—
VSS
Note 1:
Pull-up activated only with external MCLR configuration.
© 2009 Microchip Technology Inc.
DS41291F-page 7
PIC16F882/883/884/886/887
Pin Diagrams – PIC16F884/887, 44-Pin QFN
PIC16F884/887
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
VSS
VSS
NC
VDD
RE2/AN7
RE1/AN6
RE0/AN5
RA5/AN4/SS/C2OUT
RA4/T0CKI/C1OUT
RB3/AN9/PGM/C12IN2NC
RB4/AN11
RB5/AN13/T1G
RB6/ICSPCLK
RB7/ICSPDAT
RE3/MCLR/VPP
RA0/AN0/ULPWU/C12IN0RA1/AN1/C12IN1RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3//VREF+/C1IN+
RC7/RX/DT
RD4
RD5/P1B
RD6/P1C
RD7/P1D
VSS
VDD
VDD
RB0/AN12/INT
RB1/AN10/C12IN3RB2/AN8
44
43
42
41
40
39
38
37
36
35
34
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3
RD2
RD1
RD0
RC3/SCK/SCL
RC2/P1A/CCP1
RC1/T1OSCI/CCP2
RC0/T1OSO/T1CKI
44-pin QFN
DS41291F-page 8
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 4:
PIC16F884/887 44-PIN SUMMARY (QFN)
I/O
Pin
Analog
Comparators
Timers
ECCP
EUSART
MSSP
RA0
19
AN0/ULPWU
C12IN0-
—
—
—
—
Interrupt Pull-up
—
—
Basic
RA1
20
AN1
C12IN1-
—
—
—
—
—
—
—
RA2
21
AN2
C2IN+
—
—
—
—
—
—
VREF-/CVREF
RA3
22
AN3
C1IN+
—
—
—
—
—
—
VREF+
RA4
23
—
C1OUT
T0CKI
—
—
—
—
—
—
RA5
24
AN4
C2OUT
—
—
—
SS
—
—
—
RA6
33
—
—
—
—
—
—
—
—
OSC2/CLKOUT
RA7
32
—
—
—
—
—
—
—
—
OSC1/CLKIN
RB0
9
AN12
—
—
—
—
—
IOC/INT
Y
—
RB1
10
AN10
C12IN3-
—
—
—
—
IOC
Y
—
RB2
11
AN8
—
—
—
—
—
IOC
Y
—
—
RB3
12
AN9
C12IN2-
—
—
—
—
IOC
Y
PGM
RB4
14
AN11
—
—
—
—
—
IOC
Y
—
RB5
15
AN13
—
T1G
—
—
—
IOC
Y
—
RB6
16
—
—
—
—
—
—
IOC
Y
ICSPCLK
RB7
17
—
—
—
—
—
—
IOC
Y
ICSPDAT
RC0
34
—
—
T1OSO/T1CKI
—
—
—
—
—
—
RC1
35
—
—
T1OSI
CCP2
—
—
—
—
—
RC2
36
—
—
—
CCP1/P1A
—
—
—
—
—
RC3
37
—
—
—
—
—
SCK/SCL
—
—
—
RC4
42
—
—
—
—
—
SDI/SDA
—
—
—
—
RC5
43
—
—
—
—
—
SDO
—
—
RC6
44
—
—
—
—
TX/CK
—
—
—
—
RC7
1
—
—
—
—
RX/DT
—
—
—
—
RD0
38
—
—
—
—
—
—
—
—
—
—
RD1
39
—
—
—
—
—
—
—
—
RD2
40
—
—
—
—
—
—
—
—
—
RD3
41
—
—
—
—
—
—
—
—
—
RD4
2
—
—
—
—
—
—
—
—
—
—
RD5
3
—
—
—
P1B
—
—
—
—
RD6
4
—
—
—
P1C
—
—
—
—
—
RD7
5
—
—
—
P1D
—
—
—
—
—
RE0
25
AN5
—
—
—
—
—
—
—
—
RE1
26
AN6
—
—
—
—
—
—
—
—
RE2
27
AN7
—
—
—
—
—
—
—
—
RE3
18
—
—
—
—
—
—
—
Y(1)
MCLR/VPP
—
7
—
—
—
—
—
—
—
—
VDD
—
8
—
—
—
—
—
—
—
—
VDD
—
28
—
—
—
—
—
—
—
—
VDD
—
6
—
—
—
—
—
—
—
—
VSS
—
30
—
—
—
—
—
—
—
—
VSS
—
31
—
—
—
—
—
—
—
—
VSS
—
13
—
—
—
—
—
—
—
—
NC (no connect)
—
29
—
—
—
—
—
—
—
—
NC (no connect)
Note 1:
Pull-up activated only with external MCLR configuration.
© 2009 Microchip Technology Inc.
DS41291F-page 9
PIC16F882/883/884/886/887
Pin Diagrams – PIC16F884/887, 44-Pin TQFP
PIC16F884/887
33
32
31
30
29
28
27
26
25
24
23
12
13
14
15
16
17
18
19
20
21
22
1
2
3
4
5
6
7
8
9
10
11
NC
RC0/T1OSO/T1CKI
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
VSS
VDD
RE2/AN7
RE1/AN6
RE0/AN5
RA5/AN4/SS/C2OUT
RA4/T0CKI/C1OUT
NC
NC
RB4/AN11
RB5/AN13/T1G
RB6/ICSPCLK
RB7/ICSPDAT
RE3/MCLR/VPP
RA0/AN0/ULPWU/C12IN0RA1/AN1/C12IN1RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3//VREF+/C1IN+
RC7/RX/DT
RD4
RD5/P1B
RD6/P1C
RD7/P1D
VSS
VDD
RB0/AN12/INT
RB1/AN10/C12IN3RB2/AN8
RB3/AN9/PGM/C12IN2-
44
43
42
41
40
39
38
37
36
35
34
RC6/TX/CK
RC5/SDO
RC4/SDI/SDA
RD3
RD2
RD1
RD0
RC3/SCK/SCL
RC2/P1A/CCP1
RC1/T1OSCI/CCP2
NC
44-pin TQFP
DS41291F-page 10
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 5:
PIC16F884/887 44-PIN SUMMARY (TQFP)
I/O
Pin
Analog
Comparators
Timers
ECCP
EUSART
MSSP
RA0
19
AN0/ULPWU
C12IN0-
—
—
—
—
Interrupt Pull-up
—
—
Basic
RA1
20
AN1
C12IN1-
—
—
—
—
—
—
—
RA2
21
AN2
C2IN+
—
—
—
—
—
—
VREF-/CVREF
RA3
22
AN3
C1IN+
—
—
—
—
—
—
VREF+
RA4
23
—
C1OUT
T0CKI
—
—
—
—
—
—
RA5
24
AN4
C2OUT
—
—
—
SS
—
—
—
RA6
31
—
—
—
—
—
—
—
—
OSC2/CLKOUT
RA7
30
—
—
—
—
—
—
—
—
OSC1/CLKIN
RB0
8
AN12
—
—
—
—
—
IOC/INT
Y
—
RB1
9
AN10
C12IN3-
—
—
—
—
IOC
Y
—
RB2
10
AN8
—
—
—
—
—
IOC
Y
—
RB3
11
AN9
C12IN2-
—
—
—
—
IOC
Y
PGM
RB4
14
AN11
—
—
—
—
—
IOC
Y
—
RB5
15
AN13
—
T1G
—
—
—
IOC
Y
—
RB6
16
—
—
—
—
—
—
IOC
Y
ICSPCLK
—
RB7
17
—
—
—
—
—
—
IOC
Y
ICSPDAT
RC0
32
—
—
T1OSO/T1CKI
—
—
—
—
—
—
RC1
35
—
—
T1OSI
CCP2
—
—
—
—
—
RC2
36
—
—
—
CCP1/P1A
—
—
—
—
—
RC3
37
—
—
—
—
—
SCK/SCL
—
—
—
RC4
42
—
—
—
—
—
SDI/SDA
—
—
—
—
RC5
43
—
—
—
—
—
SDO
—
—
RC6
44
—
—
—
—
TX/CK
—
—
—
—
RC7
1
—
—
—
—
RX/DT
—
—
—
—
RD0
38
—
—
—
—
—
—
—
—
—
—
RD1
39
—
—
—
—
—
—
—
—
RD2
40
—
—
—
—
—
—
—
—
—
RD3
41
—
—
—
—
—
—
—
—
—
RD4
2
—
—
—
—
—
—
—
—
—
—
RD5
3
—
—
—
P1B
—
—
—
—
RD6
4
—
—
—
P1C
—
—
—
—
—
RD7
5
—
—
—
P1D
—
—
—
—
—
RE0
25
AN5
—
—
—
—
—
—
—
—
RE1
26
AN6
—
—
—
—
—
—
—
—
RE2
27
AN7
—
—
—
—
—
—
—
—
RE3
18
—
—
—
—
—
—
—
Y(1)
MCLR/VPP
—
7
—
—
—
—
—
—
—
—
VDD
—
28
—
—
—
—
—
—
—
—
VDD
—
6
—
—
—
—
—
—
—
—
VSS
—
13
—
—
—
—
—
—
—
—
NC (no connect)
—
29
—
—
—
—
—
—
—
—
VSS
—
34
—
—
—
—
—
—
—
—
NC (no connect)
—
33
—
—
—
—
—
—
—
—
NC (no connect)
—
12
—
—
—
—
—
—
—
—
NC (no connect)
Note 1:
Pull-up activated only with external MCLR configuration.
© 2009 Microchip Technology Inc.
DS41291F-page 11
PIC16F882/883/884/886/887
Table of Contents
1.0 Device Overview ........................................................................................................................................................................ 13
2.0 Memory Organization ................................................................................................................................................................. 21
3.0 I/O Ports ..................................................................................................................................................................................... 39
4.0 Oscillator Module (With Fail-Safe Clock Monitor)....................................................................................................................... 61
5.0 Timer0 Module ........................................................................................................................................................................... 73
6.0 Timer1 Module with Gate Control............................................................................................................................................... 76
7.0 Timer2 Module ........................................................................................................................................................................... 81
8.0 Comparator Module.................................................................................................................................................................... 83
9.0 Analog-to-Digital Converter (ADC) Module ................................................................................................................................ 99
10.0 Data EEPROM and Flash Program Memory Control ............................................................................................................... 111
11.0 Enhanced Capture/Compare/PWM Module ............................................................................................................................. 123
12.0 Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) ............................................................... 151
13.0 Master Synchronous Serial Port (MSSP) Module .................................................................................................................... 179
14.0 Special Features of the CPU .................................................................................................................................................... 209
15.0 Instruction Set Summary .......................................................................................................................................................... 231
16.0 Development Support............................................................................................................................................................... 241
17.0 Electrical Specifications............................................................................................................................................................ 245
18.0 DC and AC Characteristics Graphs and Tables ....................................................................................................................... 273
19.0 Packaging Information.............................................................................................................................................................. 301
Appendix A: Data Sheet Revision History.......................................................................................................................................... 313
Appendix B: Migrating from other PIC® Devices ............................................................................................................................... 313
Index .................................................................................................................................................................................................. 315
The Microchip Web Site ..................................................................................................................................................................... 323
Customer Change Notification Service .............................................................................................................................................. 323
Customer Support .............................................................................................................................................................................. 323
Reader Response .............................................................................................................................................................................. 324
Product Identification System............................................................................................................................................................. 325
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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enhanced as new volumes and updates are introduced.
If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via
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When contacting a sales office, please specify which device, revision of silicon and data sheet (include literature number) you are
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DS41291F-page 12
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
1.0
DEVICE OVERVIEW
The PIC16F882/883/884/886/887 is covered by this
data sheet. The PIC16F882/883/886 is available in 28pin PDIP, SOIC, SSOP and QFN packages. The
PIC16F884/887 is available in a 40-pin PDIP and 44pin QFN and TQFP packages. Figure 1-1 shows the
block diagram of PIC16F882/883/886 and Figure 1-2
shows a block diagram of the PIC16F884/887 device.
Table 1-1 and Table 1-2 show the corresponding pinout
descriptions.
© 2009 Microchip Technology Inc.
DS41291F-page 13
PIC16F882/883/884/886/887
FIGURE 1-1:
PIC16F882/883/886 BLOCK DIAGRAM
Configuration
PORTA
13
8
Data Bus
RA0
RA1
RA2
RA3
RA4
RA5
RA6
RA7
Program Counter
Flash
2K(2)/4K(1)/
8K X 14
Program
Memory
Program
Bus
RAM
128(2)/256(1)/
368 Bytes
File
Registers
8-Level Stack
(13-Bit)
14
RAM Addr
PORTB
RB0
RB1
RB2
RB3
RB4
RB5
RB6
RB7
9
Addr MUX
Instruction Reg
7
Direct Addr
Indirect
Addr
8
FSR Reg
PORTC
STATUS Reg
RC0
RC1
RC2
RC3
RC4
RC5
RC6
RC7
8
3
MUX
Power-up
Timer
Instruction
Decode and
Control
Oscillator
Start-up Timer
ALU
PORTE
Power-on
Reset
OSC1/CLKIN
Timing
Generation
8
Watchdog
Timer
W Reg
Brown-out
Reset
OSC2/CLKOUT
RE3
CCP2
Internal
Oscillator
Block
CCP2
MCLR
VDD
VSS
SS
SCK/SCL
SDI/SDA
SDO
P1D
P1C
T1CKI
P1B
T1G
T0CKI
RX/DT
T1OSO
TX/CK
Timer1
32 kHz
Oscillator
T1OSI
CCP1/P1A
In-Circuit
Debugger
(ICD)
Master Synchronous
VREF+
VREF-
Note
1:
2:
DS41291F-page 14
Timer2
EUSART
ECCP
Analog-To-Digital Converter
(ADC)
2 Analog Comparators
and Reference
C1IN+
C12IN0C12IN1C12IN2C12IN3C1OUT
C2IN+
C2OUT
Timer1
AN0
AN1
AN2
AN3
AN4
AN8
AN9
AN10
AN11
AN12
AN13
Timer0
PIC16F883 only.
PIC16F882 only.
Serial Port (MSSP)
VREF+
VREFCVREF
8
EEDATA
128(2)/
256 Bytes
Data
EEPROM
EEADDR
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
PIC16F884/PIC16F887 BLOCK DIAGRAM
Configuration
PORTA
13
8
Data Bus
RA0
RA1
RA2
RA3
RA4
RA5
RA6
RA7
Program Counter
Flash
4K(1)/8K X 14
Program
Memory
Program
Bus
RAM
256(1)/368 Bytes
File
Registers
8-Level Stack
(13-Bit)
PORTB
14
RAM Addr
RB0
RB1
RB2
RB3
RB4
RB5
RB6
RB7
9
Addr MUX
Instruction Reg
7
Direct Addr
Indirect
Addr
8
FSR Reg
STATUS Reg
PORTC
RC0
RC1
RC2
RC3
RC4
RC5
RC6
RC7
8
3
MUX
Power-up
Timer
Instruction
Decode and
Control
Oscillator
Start-up Timer
ALU
Power-on
Reset
OSC1/CLKIN
Timing
Generation
PORTD
8
Watchdog
Timer
W Reg
CCP2
Brown-out
Reset
OSC2/CLKOUT
RD0
RD1
RD2
RD3
RD4
RD5
RD6
RD7
Internal
Oscillator
Block
CCP2
MCLR
VDD
PORTE
VSS
RE0
RE1
RE2
RE3
SCK/SCL
SDI/SDA
SDO
P1D
P1C
T1CKI
P1B
T1G
T0CKI
RX/DT
T1OSO
TX/CK
Timer1
32 kHz
Oscillator
T1OSI
CCP1/P1A
In-Circuit
Debugger
(ICD)
SS
FIGURE 1-2:
Master Synchronous
Timer1
VREF+
VREF-
Timer2
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
AN8
AN9
AN10
AN11
AN12
AN13
Analog-To-Digital Converter
(ADC)
Note
1:
EUSART
ECCP
2 Analog Comparators
and Reference
C1IN+
C12IN0C12IN1C12IN2C12IN3C1OUT
C2IN+
C2OUT
Timer0
Serial Port (MSSP)
VREF+
VREFCVREF
8
EEDATA
256 Bytes
Data
EEPROM
EEADDR
PIC16F884 only.
© 2009 Microchip Technology Inc.
DS41291F-page 15
PIC16F882/883/884/886/887
TABLE 1-1:
PIC16F882/883/886 PINOUT DESCRIPTION
Name
RA0/AN0/ULPWU/C12IN0-
RA1/AN1/C12IN1-
RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3/VREF+/C1IN+
RA4/T0CKI/C1OUT
RA5/AN4/SS/C2OUT
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
RB0/AN12/INT
RB1/AN10/P1C/C12IN3-
RB2/AN8/P1B
Legend:
Function
Input
Type
RA0
TTL
Description
CMOS General purpose I/O.
AN0
AN
—
A/D Channel 0 input.
ULPWU
AN
—
Ultra Low-Power Wake-up input.
—
Comparator C1 or C2 negative input.
C12IN0-
AN
RA1
TTL
AN1
AN
C12IN1-
AN
RA2
TTL
CMOS General purpose I/O.
—
A/D Channel 1 input.
—
Comparator C1 or C2 negative input.
CMOS General purpose I/O.
AN2
AN
—
A/D Channel 2.
VREF-
AN
—
A/D Negative Voltage Reference input.
CVREF
—
AN
Comparator Voltage Reference output.
C2IN+
AN
—
Comparator C2 positive input.
RA3
TTL
—
General purpose I/O.
AN3
AN
—
A/D Channel 3.
VREF+
AN
—
Programming voltage.
C1IN+
AN
—
Comparator C1 positive input.
RA4
TTL
T0CKI
ST
C1OUT
—
CMOS General purpose I/O.
—
Timer0 clock input.
CMOS Comparator C1 output.
RA5
TTL
AN4
AN
—
A/D Channel 4.
SS
ST
—
Slave Select input.
CMOS General purpose I/O.
C2OUT
—
RA6
TTL
OSC2
—
XTAL
CLKOUT
—
CMOS FOSC/4 output.
RA7
TTL
OSC1
XTAL
CMOS Comparator C2 output.
CMOS General purpose I/O.
Master Clear with internal pull-up.
CMOS General purpose I/O.
—
Crystal/Resonator.
—
External clock input/RC oscillator connection.
CLKIN
ST
RB0
TTL
AN12
AN
—
A/D Channel 12.
INT
ST
—
External interrupt.
RB1
TTL
AN10
AN
P1C
—
C12IN3-
AN
RB2
TTL
AN8
AN
P1B
—
AN = Analog input or output
TTL = TTL compatible input
HV = High Voltage
DS41291F-page 16
Output
Type
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
A/D Channel 10.
CMOS PWM output.
—
Comparator C1 or C2 negative input.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
A/D Channel 8.
CMOS PWM output.
CMOS = CMOS compatible input or output
OD = Open Drain
ST
= Schmitt Trigger input with CMOS levels
XTAL = Crystal
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 1-1:
PIC16F882/883/886 PINOUT DESCRIPTION (CONTINUED)
Name
RB3/AN9/PGM/C12IN2-
RB4/AN11/P1D
RB5/AN13/T1G
RB6/ICSPCLK
RB7/ICSPDAT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/P1A/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
RC7/RX/DT
RE3/MCLR/VPP
Function
Input
Type
RB3
TTL
Output
Type
Description
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
AN9
AN
—
PGM
ST
—
A/D Channel 9.
Low-voltage ICSP™ Programming enable pin.
C12IN2-
AN
—
Comparator C1 or C2 negative input.
RB4
TTL
AN11
AN
P1D
—
RB5
TTL
AN13
AN
—
A/D Channel 13.
T1G
ST
—
Timer1 Gate input.
RB6
TTL
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
A/D Channel 11.
CMOS PWM output.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
ICSPCLK
ST
RB7
TTL
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
ICSPDAT
ST
CMOS ICSP™ Data I/O.
RC0
ST
CMOS General purpose I/O.
T1OSO
—
CMOS Timer1 oscillator output.
T1CKI
ST
—
Serial Programming Clock.
Timer1 clock input.
RC1
ST
T1OSI
ST
CMOS General purpose I/O.
CCP2
ST
CMOS Capture/Compare/PWM2.
RC2
ST
CMOS General purpose I/O.
P1A
—
CMOS PWM output.
—
Timer1 oscillator input.
CCP1
ST
CMOS Capture/Compare/PWM1.
RC3
ST
CMOS General purpose I/O.
SCK
ST
CMOS SPI clock.
SCL
ST
OD
I2C™ clock.
RC4
ST
SDI
ST
CMOS General purpose I/O.
—
SPI data input.
SDA
ST
OD
I2C data input/output.
RC5
ST
CMOS General purpose I/O.
SDO
—
CMOS SPI data output.
RC6
ST
CMOS General purpose I/O.
TX
—
CMOS EUSART asynchronous transmit.
CK
ST
CMOS EUSART synchronous clock.
RC7
ST
CMOS General purpose I/O.
RX
ST
DT
ST
RE3
TTL
—
General purpose input.
MCLR
ST
—
Master Clear with internal pull-up.
Programming voltage.
—
EUSART asynchronous input.
CMOS EUSART synchronous data.
VPP
HV
—
VSS
VSS
Power
—
Ground reference.
VDD
VDD
Power
—
Positive supply.
Legend:
AN = Analog input or output
TTL = TTL compatible input
HV = High Voltage
© 2009 Microchip Technology Inc.
CMOS = CMOS compatible input or output
OD = Open Drain
ST
= Schmitt Trigger input with CMOS levels
XTAL = Crystal
DS41291F-page 17
PIC16F882/883/884/886/887
TABLE 1-2:
PIC16F884/887 PINOUT DESCRIPTION
Name
RA0/AN0/ULPWU/C12IN0-
RA1/AN1/C12IN1-
RA2/AN2/VREF-/CVREF/C2IN+
RA3/AN3/VREF+/C1IN+
RA4/T0CKI/C1OUT
RA5/AN4/SS/C2OUT
RA6/OSC2/CLKOUT
RA7/OSC1/CLKIN
RB0/AN12/INT
RB1/AN10/C12IN3-
Function
Input
Type
RA0
TTL
AN0
AN
CMOS General purpose I/O.
—
A/D Channel 0 input.
ULPWU
AN
—
Ultra Low-Power Wake-up input.
AN
—
Comparator C1 or C2 negative input.
RA1
TTL
AN1
AN
C12IN1-
AN
RA2
TTL
CMOS General purpose I/O.
—
A/D Channel 1 input.
—
Comparator C1 or C2 negative input.
CMOS General purpose I/O.
AN2
AN
—
A/D Channel 2.
VREF-
AN
—
A/D Negative Voltage Reference input.
CVREF
—
AN
Comparator Voltage Reference output.
C2IN+
AN
—
Comparator C2 positive input.
RA3
TTL
AN3
AN
CMOS General purpose I/O.
—
A/D Channel 3.
VREF+
AN
—
A/D Positive Voltage Reference input.
C1IN+
AN
—
Comparator C1 positive input.
RA4
TTL
T0CKI
ST
CMOS General purpose I/O.
—
Timer0 clock input.
C1OUT
—
RA5
TTL
AN4
AN
—
A/D Channel 4.
SS
ST
—
Slave Select input.
C2OUT
—
RA6
TTL
OSC2
—
CLKOUT
—
CMOS Comparator C1 output.
CMOS General purpose I/O.
CMOS Comparator C2 output.
CMOS General purpose I/O.
XTAL
Crystal/Resonator.
CMOS FOSC/4 output.
RA7
TTL
OSC1
XTAL
—
Crystal/Resonator.
CLKIN
ST
—
External clock input/RC oscillator connection.
RB0
TTL
AN12
AN
—
A/D Channel 12.
INT
ST
—
External interrupt.
RB1
TTL
AN10
AN
C12IN3-
AN
RB2
TTL
AN8
AN
RB3/AN9/PGM/C12IN2-
RB3
TTL
CMOS General purpose I/O.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
A/D Channel 10.
—
Comparator C1 or C2 negative input.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
A/D Channel 8.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
AN9
AN
—
PGM
ST
—
Low-voltage ICSP™ Programming enable pin.
C12IN2-
AN
—
Comparator C1 or C2 negative input.
AN = Analog input or output
TTL = TTL compatible input
HV = High Voltage
DS41291F-page 18
Description
C12IN0-
RB2/AN8
Legend:
Output
Type
A/D Channel 9.
CMOS = CMOS compatible input or output
OD = Open Drain
ST
= Schmitt Trigger input with CMOS levels
XTAL = Crystal
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 1-2:
PIC16F884/887 PINOUT DESCRIPTION (CONTINUED)
Name
RB4/AN11
RB5/AN13/T1G
RB6/ICSPCLK
RB7/ICSPDAT
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/P1A/CCP1
RC3/SCK/SCL
RC4/SDI/SDA
RC5/SDO
RC6/TX/CK
Function
Input
Type
RB4
TTL
Output
Type
Description
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
AN11
AN
RB5
TTL
—
A/D Channel 11.
AN13
AN
—
A/D Channel 13.
T1G
ST
—
Timer1 Gate input.
RB6
TTL
ICSPCLK
ST
RB7
TTL
ICSPDAT
ST
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
—
Serial Programming Clock.
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up.
TTL
ICSP™ Data I/O.
RC0
ST
T1OSO
—
CMOS General purpose I/O.
XTAL
T1CKI
ST
—
RC1
ST
T1OSI
XTAL
CCP2
ST
CMOS Capture/Compare/PWM2.
RC2
ST
CMOS General purpose I/O.
P1A
ST
CMOS PWM output.
Timer1 oscillator output.
Timer1 clock input.
CMOS General purpose I/O.
—
Timer1 oscillator input.
CCP1
—
CMOS Capture/Compare/PWM1.
RC3
ST
CMOS General purpose I/O.
SCK
ST
CMOS SPI clock.
SCL
ST
RC4
ST
SDI
ST
—
SPI data input.
SDA
ST
OD
I2C data input/output.
RC5
ST
OD
I2C™ clock.
CMOS General purpose I/O.
CMOS General purpose I/O.
SDO
—
CMOS SPI data output.
RC6
ST
CMOS General purpose I/O.
TX
—
CMOS EUSART asynchronous transmit.
CK
ST
CMOS EUSART synchronous clock.
RC7
ST
CMOS General purpose I/O.
RX
ST
DT
ST
CMOS EUSART synchronous data.
RD0
RD0
TTL
CMOS General purpose I/O.
RD1
RD1
TTL
CMOS General purpose I/O.
RD2
RD2
TTL
CMOS General purpose I/O.
RD3
RD3
TTL
CMOS General purpose I/O.
RD4
RD4
TTL
CMOS General purpose I/O.
RD5/P1B
RD5
TTL
CMOS General purpose I/O.
P1B
—
RD6
TTL
P1C
—
RC7/RX/DT
RD6/P1C
Legend:
AN = Analog input or output
TTL = TTL compatible input
HV = High Voltage
© 2009 Microchip Technology Inc.
—
EUSART asynchronous input.
CMOS PWM output.
CMOS General purpose I/O.
CMOS PWM output.
CMOS = CMOS compatible input or output
OD = Open Drain
ST
= Schmitt Trigger input with CMOS levels
XTAL = Crystal
DS41291F-page 19
PIC16F882/883/884/886/887
TABLE 1-2:
PIC16F884/887 PINOUT DESCRIPTION (CONTINUED)
Function
Input
Type
RD7/P1D
RD7
TTL
P1D
AN
RE0/AN5
RE0
TTL
AN5
AN
RE1/AN6
RE1
TTL
AN6
AN
RE2/AN7
RE2
TTL
Name
RE3/MCLR/VPP
Output
Type
Description
CMOS General purpose I/O.
—
PWM output.
CMOS General purpose I/O.
—
A/D Channel 5.
CMOS General purpose I/O.
—
A/D Channel 6.
CMOS General purpose I/O.
AN7
AN
—
A/D Channel 7.
RE3
TTL
—
General purpose input.
MCLR
ST
—
Master Clear with internal pull-up.
VPP
HV
—
Programming voltage.
VSS
VSS
Power
—
Ground reference.
VDD
VDD
Power
—
Positive supply.
Legend:
AN = Analog input or output
TTL = TTL compatible input
HV = High Voltage
DS41291F-page 20
CMOS = CMOS compatible input or output
OD = Open Drain
ST
= Schmitt Trigger input with CMOS levels
XTAL = Crystal
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.0
MEMORY ORGANIZATION
2.1
Program Memory Organization
The PIC16F882/883/884/886/887 has a 13-bit program
counter capable of addressing a 2K x 14 (0000h-07FFh)
for the PIC16F882, 4K x 14 (0000h-0FFFh) for the
PIC16F883/PIC16F884, and 8K x 14 (0000h-1FFFh) for
the PIC16F886/PIC16F887 program memory space.
Accessing a location above these boundaries will cause
a wrap-around within the first 8K x 14 space. The Reset
vector is at 0000h and the interrupt vector is at 0004h
(see Figures 2-2 and 2-3).
FIGURE 2-1:
FIGURE 2-2:
PC<12:0>
CALL, RETURN
RETFIE, RETLW
Stack Level 2
Stack Level 8
PC<12:0>
13
13
Stack Level 1
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC16F882
CALL, RETURN
RETFIE, RETLW
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC16F883/PIC16F884
On-Chip
Program
Memory
Stack Level 1
Reset Vector
0000h
Interrupt Vector
0004h
0005h
Page 0
07FFh
0800h
Page 1
0FFFh
Stack Level 2
FIGURE 2-3:
Stack Level 8
Reset Vector
0000h
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC16F886/PIC16F887
PC<12:0>
Interrupt Vector
On-Chip
Program
Memory
0004h
0005h
CALL, RETURN
RETFIE, RETLW
13
Page 0
Stack Level 1
07FFh
Stack Level 2
Stack Level 8
Reset Vector
0000h
Interrupt Vector
0004h
0005h
Page 0
07FFh
0800h
On-Chip
Program
Memory
Page 1
0FFFh
1000h
Page 2
17FFh
1800h
Page 3
1FFFh
© 2009 Microchip Technology Inc.
DS41291F-page 21
PIC16F882/883/884/886/887
2.2
Data Memory Organization
The data memory (see Figures 2-2 and 2-3) is
partitioned into four banks which contain the General
Purpose Registers (GPR) and the Special Function
Registers (SFR). The Special Function Registers are
located in the first 32 locations of each bank. The
General Purpose Registers, implemented as static RAM,
are located in the last 96 locations of each Bank.
Register locations F0h-FFh in Bank 1, 170h-17Fh in
Bank 2 and 1F0h-1FFh in Bank 3, point to addresses
70h-7Fh in Bank 0. The actual number of General
Purpose Resisters (GPR) implemented in each Bank
depends on the device. Details are shown in Figures 2-5
and 2-6. All other RAM is unimplemented and returns ‘0’
when read. RP<1:0> of the STATUS register are the
bank select bits:
RP1 RP0
0
0
→Bank 0 is selected
0
1
→Bank 1 is selected
1
0
→Bank 2 is selected
1
1
→Bank 3 is selected
2.2.1
GENERAL PURPOSE REGISTER
FILE
The register file is organized as 128 x 8 in the
PIC16F882, 256 x 8 in the PIC16F883/PIC16F884, and
368 x 8 in the PIC16F886/PIC16F887. Each register is
accessed, either directly or indirectly, through the File
Select Register (FSR) (see Section 2.4 “Indirect
Addressing, INDF and FSR Registers”).
2.2.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers are registers used by
the CPU and peripheral functions for controlling the
desired operation of the device (see Table 2-1). These
registers are static RAM.
The special registers can be classified into two sets:
core and peripheral. The Special Function Registers
associated with the “core” are described in this section.
Those related to the operation of the peripheral
features are described in the section of that peripheral
feature.
DS41291F-page 22
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 2-4:
PIC16F882 SPECIAL FUNCTION REGISTERS
File
File
Address
File
Address
File
Address
Address
Indirect addr. (1)
00h
Indirect addr. (1)
80h
Indirect addr. (1)
100h
Indirect addr. (1)
180h
TMR0
01h
OPTION_REG
81h
TMR0
101h
OPTION_REG
181h
PCL
02h
PCL
82h
PCL
102h
PCL
182h
STATUS
03h
STATUS
83h
STATUS
103h
STATUS
183h
FSR
04h
FSR
84h
FSR
104h
FSR
184h
PORTA
05h
TRISA
85h
WDTCON
105h
SRCON
185h
PORTB
06h
TRISB
86h
PORTB
106h
TRISB
186h
PORTC
07h
TRISC
87h
CM1CON0
107h
BAUDCTL
187h
188h
88h
CM2CON0
108h
ANSEL
PORTE
08h
09h
TRISE
89h
CM2CON1
109h
ANSELH
189h
PCLATH
0Ah
PCLATH
8Ah
PCLATH
10Ah
PCLATH
18Ah
INTCON
0Bh
INTCON
8Bh
INTCON
10Bh
INTCON
18Bh
PIR1
0Ch
PIE1
8Ch
EEDAT
10Ch
EECON1
18Ch
PIR2
0Dh
PIE2
8Dh
EEADR
10Dh
EECON2(1)
18Dh
TMR1L
0Eh
PCON
8Eh
EEDATH
10Eh
Reserved
18Eh
TMR1H
0Fh
OSCCON
8Fh
EEADRH
10Fh
Reserved
18Fh
T1CON
10h
OSCTUNE
90h
110h
190h
TMR2
11h
SSPCON2
91h
111h
191h
T2CON
12h
PR2
92h
112h
192h
193h
SSPBUF
13h
SSPADD
93h
113h
SSPCON
14h
SSPSTAT
94h
114h
194h
CCPR1L
15h
WPUB
95h
115h
195h
CCPR1H
16h
IOCB
96h
116h
196h
CCP1CON
17h
VRCON
97h
117h
197h
RCSTA
18h
TXSTA
98h
118h
198h
TXREG
19h
SPBRG
99h
119h
199h
19Ah
RCREG
1Ah
SPBRGH
9Ah
11Ah
CCPR2L
1Bh
PWM1CON
9Bh
11Bh
19Bh
CCPR2H
1Ch
ECCPAS
9Ch
11Ch
19Ch
CCP2CON
1Dh
PSTRCON
9Dh
11Dh
19Dh
ADRESH
1Eh
ADRESL
9Eh
11Eh
19Eh
ADCON0
1Fh
ADCON1
9Fh
11Fh
19Fh
20h
General
Purpose
Registers
A0h
120h
1A0h
General
Purpose
Registers
32 Bytes
BFh
C0h
96 Bytes
EFh
7Fh
Bank 0
accesses
70h-7Fh
F0h
FFh
Bank 1
16Fh
accesses
70h-7Fh
Bank 2
170h
17Fh
1EFh
accesses
70h-7Fh
1F0h
1FFh
Bank 3
Unimplemented data memory locations, read as ‘0’.
Note 1: Not a physical register.
© 2009 Microchip Technology Inc.
DS41291F-page 23
PIC16F882/883/884/886/887
FIGURE 2-5:
PIC16F883/PIC16F884 SPECIAL FUNCTION REGISTERS
File
File
File
File
Address
Address
Address
Address
Indirect addr. (1)
00h
Indirect addr. (1)
80h
Indirect addr. (1)
100h
Indirect addr. (1)
180h
TMR0
01h
OPTION_REG
81h
TMR0
101h
OPTION_REG
181h
PCL
02h
PCL
82h
PCL
102h
PCL
182h
STATUS
03h
STATUS
83h
STATUS
103h
STATUS
183h
FSR
04h
FSR
84h
FSR
104h
FSR
184h
PORTA
05h
TRISA
85h
WDTCON
105h
SRCON
185h
PORTB
06h
TRISB
86h
PORTB
106h
TRISB
186h
PORTC
07h
TRISC
87h
CM1CON0
107h
BAUDCTL
187h
PORTD(2)
08h
TRISD(2)
88h
CM2CON0
108h
ANSEL
188h
PORTE
09h
TRISE
89h
CM2CON1
109h
ANSELH
189h
PCLATH
0Ah
PCLATH
8Ah
PCLATH
10Ah
PCLATH
18Ah
INTCON
0Bh
INTCON
8Bh
INTCON
10Bh
INTCON
18Bh
PIR1
0Ch
PIE1
8Ch
EEDAT
10Ch
EECON1
18Ch
PIR2
0Dh
PIE2
8Dh
EEADR
10Dh
EECON2(1)
18Dh
TMR1L
0Eh
PCON
8Eh
EEDATH
10Eh
Reserved
18Eh
TMR1H
0Fh
OSCCON
8Fh
EEADRH
10Fh
Reserved
18Fh
T1CON
10h
OSCTUNE
90h
110h
190h
TMR2
11h
SSPCON2
91h
111h
191h
T2CON
12h
PR2
92h
112h
192h
SSPBUF
13h
SSPADD
93h
113h
193h
SSPCON
14h
SSPSTAT
94h
114h
194h
CCPR1L
15h
WPUB
95h
115h
195h
CCPR1H
16h
IOCB
96h
116h
196h
CCP1CON
17h
VRCON
97h
117h
197h
RCSTA
18h
TXSTA
98h
118h
198h
TXREG
19h
SPBRG
99h
119h
199h
RCREG
1Ah
SPBRGH
9Ah
11Ah
19Ah
CCPR2L
1Bh
PWM1CON
9Bh
11Bh
19Bh
CCPR2H
1Ch
ECCPAS
9Ch
11Ch
19Ch
CCP2CON
1Dh
PSTRCON
9Dh
11Dh
19Dh
ADRESH
1Eh
ADRESL
9Eh
11Eh
19Eh
ADCON0
1Fh
ADCON1
9Fh
11Fh
19Fh
120h
1A0h
20h
General
Purpose
Registers
General
Purpose
Registers
80 Bytes
General
Purpose
Registers
80 Bytes
EFh
96 Bytes
7Fh
Bank 0
A0h
accesses
70h-7Fh
F0h
FFh
Bank 1
16Fh
accesses
70h-7Fh
Bank 2
170h
17Fh
1EFh
accesses
70h-7Fh
1F0h
1FFh
Bank 3
Unimplemented data memory locations, read as ‘0’.
Note 1: Not a physical register.
2: PIC16F884 only.
DS41291F-page 24
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 2-6:
PIC16F886/PIC16F887 SPECIAL FUNCTION REGISTERS
File
File
File
File
Address
Address
Address
Address
Indirect addr. (1)
00h
Indirect addr. (1)
80h
Indirect addr. (1)
100h
Indirect addr. (1)
180h
TMR0
01h
OPTION_REG
81h
TMR0
101h
OPTION_REG
181h
PCL
02h
PCL
82h
PCL
102h
PCL
182h
STATUS
03h
STATUS
83h
STATUS
103h
STATUS
183h
FSR
04h
FSR
84h
FSR
104h
FSR
184h
PORTA
05h
TRISA
85h
WDTCON
105h
SRCON
185h
PORTB
06h
TRISB
86h
PORTB
106h
TRISB
186h
PORTC
07h
TRISC
87h
CM1CON0
107h
BAUDCTL
187h
PORTD(2)
08h
TRISD(2)
88h
CM2CON0
108h
ANSEL
188h
PORTE
09h
TRISE
89h
CM2CON1
109h
ANSELH
189h
PCLATH
0Ah
PCLATH
8Ah
PCLATH
10Ah
PCLATH
18Ah
INTCON
0Bh
INTCON
8Bh
INTCON
10Bh
INTCON
18Bh
PIR1
0Ch
PIE1
8Ch
EEDAT
10Ch
EECON1
18Ch
PIR2
0Dh
PIE2
8Dh
EEADR
10Dh
EECON2(1)
18Dh
TMR1L
0Eh
PCON
8Eh
EEDATH
10Eh
Reserved
18Eh
TMR1H
0Fh
OSCCON
8Fh
EEADRH
10Fh
Reserved
18Fh
T1CON
10h
OSCTUNE
90h
110h
190h
TMR2
11h
SSPCON2
91h
111h
191h
T2CON
12h
PR2
92h
112h
192h
SSPBUF
13h
SSPADD
93h
113h
193h
SSPCON
14h
SSPSTAT
94h
114h
194h
CCPR1L
15h
WPUB
95h
115h
195h
CCPR1H
16h
IOCB
96h
CCP1CON
17h
VRCON
97h
RCSTA
18h
TXSTA
98h
TXREG
19h
SPBRG
99h
General
Purpose
Registers
116h
16 Bytes
119h
117h
118h
General
Purpose
Registers
196h
16 Bytes
199h
197h
198h
RCREG
1Ah
SPBRGH
9Ah
11Ah
19Ah
CCPR2L
1Bh
PWM1CON
9Bh
11Bh
19Bh
CCPR2H
1Ch
ECCPAS
9Ch
11Ch
19Ch
CCP2CON
1Dh
PSTRCON
9Dh
11Dh
19Dh
ADRESH
1Eh
ADRESL
9Eh
11Eh
19Eh
ADCON0
1Fh
ADCON1
9Fh
11Fh
19Fh
20h
General
Purpose
Registers
3Fh
96 Bytes
6Fh
40h
General
Purpose
Registers
A0h
80 Bytes
70h
7Fh
Bank 0
120h
General
Purpose
Registers
80 Bytes
EFh
accesses
70h-7Fh
F0h
FFh
Bank 1
1A0h
General
Purpose
Registers
80 Bytes
16Fh
accesses
70h-7Fh
Bank 2
170h
17Fh
1EFh
accesses
70h-7Fh
1F0h
1FFh
Bank 3
Unimplemented data memory locations, read as ‘0’.
Note 1: Not a physical register.
2: PIC16F887 only.
© 2009 Microchip Technology Inc.
DS41291F-page 25
PIC16F882/883/884/886/887
TABLE 2-1:
Addr
Name
PIC16F882/883/884/886/887 SPECIAL FUNCTION REGISTERS SUMMARY BANK 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Page
Bank 0
00h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
xxxx xxxx
37,217
01h
TMR0
Timer0 Module Register
xxxx xxxx
73,217
02h
PCL
Program Counter’s (PC) Least Significant Byte
0000 0000
37,217
03h
STATUS
29,217
04h
FSR
05h
PORTA(3)
06h
PORTB(3)
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
48,217
07h
PORTC(3)
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx
53,217
08h
PORTD(3,4)
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
xxxx xxxx
57,217
09h
PORTE(3)
—
—
—
—
RE3
RE2(4)
RE1(4)
RE0(4)
---- xxxx
59,217
0Ah
PCLATH
—
—
—
---0 0000
37,217
0Bh
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF(1)
0000 000x
31,217
0Ch
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
34,217
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
IRP
RP1
RP0
TO
PD
Z
DC
C
0001 1xxx
xxxx xxxx
37,217
RA4
RA3
RA2
RA1
RA0
xxxx xxxx
39,217
Indirect Data Memory Address Pointer
RA7
RA6
RA5
Write Buffer for upper 5 bits of Program Counter
0Dh
PIR2
0000 00-0
35,217
0Eh
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
76,217
0Fh
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
76,217
0000 0000
79,217
10h
T1CON
11h
TMR2
12h
T2CON
T1GINV
TMR1GE
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
Timer2 Module Register
—
TOUTPS3 TOUTPS2
TOUTPS1
TOUTPS0
0000 0000
81,217
82,217
TMR2ON
T2CKPS1
T2CKPS0
-000 0000
xxxx xxxx
183,217
SSPM2
SSPM1
SSPM0
0000 0000
181,217
xxxx xxxx
126,217
13h
SSPBUF
14h
SSPCON(2)
15h
CCPR1L
Capture/Compare/PWM Register 1 Low Byte (LSB)
16h
CCPR1H
Capture/Compare/PWM Register 1 High Byte (MSB)
xxxx xxxx
126,217
17h
CCP1CON
P1M1
P1M0
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
0000 0000
124,217
18h
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
161,217
19h
TXREG
EUSART Transmit Data Register
0000 0000
153,217
1Ah
RCREG
EUSART Receive Data Register
0000 0000
158,217
1Bh
CCPR2L
Capture/Compare/PWM Register 2 Low Byte (LSB)
xxxx xxxx
126,217
1Ch
CCPR2H
Capture/Compare/PWM Register 2 High Byte (MSB)
xxxx xxxx
126,218
1Dh
CCP2CON
--00 0000
125,218
1Eh
ADRESH
1Fh
ADCON0
Legend:
Note 1:
2:
3:
4:
Synchronous Serial Port Receive Buffer/Transmit Register
WCOL
—
SSPOV
—
SSPEN
DC2B1
CKP
DC2B0
SSPM3
CCP2M3
CCP2M2
CCP2M1
CCP2M0
A/D Result Register High Byte
ADCS1
ADCS0
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
xxxx xxxx
99,218
0000 0000
104,218
– = Unimplemented locations read as ‘0’, u = unchanged, x = unknown, q = value depends on condition, shaded = unimplemented
MCLR and WDT Reset do not affect the previous value data latch. The RBIF bit will be cleared upon Reset but will set again if the
mismatch exists.
When SSPCON register bits SSPM<3:0> = 1001, any reads or writes to the SSPADD SFR address are accessed through the SSPMSK
register. See Registers • and 13-4 for more detail.
Port pins with analog functions controlled by the ANSEL and ANSELH registers will read ‘0’ immediately after a Reset even though the
data latches are either undefined (POR) or unchanged (other Resets).
PIC16F884/PIC16F887 only.
DS41291F-page 26
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 2-2:
Addr
Name
PIC16F882/883/884/886/887 SPECIAL FUNCTION REGISTERS SUMMARY BANK 1
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Page
Bank 1
80h
INDF
81h
OPTION_REG
Addressing this location uses contents of FSR to address data memory (not a physical register)
82h
PCL
83h
STATUS
84h
FSR
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
PD
Z
DC
C
Program Counter’s (PC) Least Significant Byte
IRP
RP1
RP0
TO
Indirect Data Memory Address Pointer
xxxx xxxx
37,217
1111 1111
30,218
0000 0000
37,217
0001 1xxx
29,217
xxxx xxxx
37,217
39,218
85h
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
86h
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111
48,218
87h
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
53,218
88h
TRISD(3)
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
89h
TRISE
—
—
—
—
TRISE3
8Ah
PCLATH
—
—
—
8Bh
INTCON
GIE
PEIE
T0IE
8Ch
PIE1
—
ADIE
8Dh
PIE2
OSFIE
C2IE
8Eh
PCON
—
8Fh
OSCCON
—
90h
OSCTUNE
—
91h
SSPCON2
GCEN
TRISE2(3) TRISE1(3) TRISE0(3)
Write Buffer for the upper 5 bits of the Program Counter
1111 1111
57,218
---- 1111
59,218
---0 0000
37,217
0000 000x
31,217
T0IF
INTF
RBIF(1)
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
32,218
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
33,218
—
—
POR
BOR
--01 --qq
36,218
OSTS
HTS
LTS
SCS
-110 q000
62,218
TUN3
TUN2
TUN1
TUN0
---0 0000
66,218
RCEN
PEN
RSEN
SEN
0000 0000
181,218
INTE
RBIE
RCIE
TXIE
C1IE
EEIE
—
ULPWUE
SBOREN
IRCF2
IRCF1
IRCF0
—
—
TUN4
ACKSTAT
ACKDT
ACKEN
92h
PR2
Timer2 Period Register
1111 1111
81,218
93h
SSPADD(2)
Synchronous Serial Port (I2C mode) Address Register
0000 0000
189,218
93h
SSPMSK(2)
1111 1111
189,218
94h
SSPSTAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000
189,218
95h
WPUB
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
1111 1111
49,218
96h
IOCB
IOCB7
IOCB6
IOCB5
IOCB4
IOCB3
IOCB2
IOCB1
IOCB0
0000 0000
49,218
97h
VRCON
VREN
VROE
VRR
VRSS
VR3
VR2
VR1
VR0
0000 0000
97,218
98h
TXSTA
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
160,218
MSK7
MSK6
MSK5
MSK4
MSK3
MSK2
MSK1
MSK0
99h
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
163,218
9Ah
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
163,218
PRSEN
PDC6
PDC5
PDC4
9Bh
PWM1CON
9Ch
ECCPAS
9Dh
PSTRCON
9Eh
ADRESL
9Fh
ADCON1
Legend:
Note 1:
2:
3:
ECCPASE ECCPAS2 ECCPAS1 ECCPAS0
—
—
—
STRSYNC
PDC3
PDC2
PDC1
PDC0
0000 0000
145,218
PSSAC1
PSSAC0
PSSBD1
PSSBD0
0000 0000
142,218
STRD
STRC
STRB
STRA
---0 0001
146,218
A/D Result Register Low Byte
ADFM
—
VCFG1
VCFG0
—
—
—
—
xxxx xxxx
99,218
0-00 ----
105,218
– = Unimplemented locations read as ‘0’, u = unchanged, x = unknown, q = value depends on condition, shaded = unimplemented
MCLR and WDT Reset do not affect the previous value data latch. The RBIF bit will be cleared upon Reset but will set again if the
mismatch exists.
Accessible only when SSPCON register bits SSPM<3:0> = 1001.
PIC16F884/PIC16F887 only.
© 2009 Microchip Technology Inc.
DS41291F-page 27
PIC16F882/883/884/886/887
TABLE 2-3:
Addr
PIC16F882/883/884/886/887 SPECIAL FUNCTION REGISTERS SUMMARY BANK 2
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Page
Bank 2
100h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
xxxx xxxx
37,217
101h
TMR0
Timer0 Module Register
xxxx xxxx
73,217
102h
PCL
Program Counter’s (PC) Least Significant Byte
0000 0000
37,217
103h
STATUS
0001 1xxx
29,217
IRP
RP1
RP0
TO
PD
Z
DC
C
xxxx xxxx
37,217
WDTPS3
WDTPS2
WDTPS1
WDTPS0
SWDTEN
---0 1000
225,218
104h
FSR
105h
WDTCON
Indirect Data Memory Address Pointer
106h
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
48,217
107h
CM1CON0
C1ON
C1OUT
C1OE
C1POL
—
C1R
C1CH1
C1CH0
0000 -000
88,218
108h
CM2CON0
C2ON
C2OUT
C2OE
C2POL
—
C2R
C2CH1
C2CH0
0000 -000
89,218
109h
CM2CON1
MC1OUT
MC2OUT
C1RSEL
C2RSEL
—
—
T1GSS
C2SYNC
0000 --10
91,219
---0 0000
37,217
—
—
—
10Ah PCLATH
—
—
—
10Bh INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF(1)
0000 000x
31,217
10Ch EEDAT
EEDAT7
EEDAT6
EEDAT5
EEDAT4
EEDAT3
EEDAT2
EEDAT1
EEDAT0
0000 0000
112,219
10Dh EEADR
EEADR7
EEADR6
EEADR5
EEADR4
EEADR3
EEADR2
EEADR1
EEADR0
0000 0000
112,219
10Eh EEDATH
—
—
EEDATH5
EEDATH4
EEDATH3
EEDATH2
EEDATH1
EEDATH0
--00 0000
112,219
10Fh EEADRH
—
—
—
EEADRH4(2) EEADRH3 EEADRH2 EEADRH1 EEADRH0 ---- 0000
112,219
Legend:
Note 1:
– = Unimplemented locations read as ‘0’, u = unchanged, x = unknown, q = value depends on condition, shaded = unimplemented
MCLR and WDT Reset does not affect the previous value data latch. The RBIF bit will be cleared upon Reset but will set again if the
mismatch exists.
PIC16F886/PIC16F887 only.
2:
TABLE 2-4:
Addr
Write Buffer for the upper 5 bits of the Program Counter
PIC16F882/883/884/886/887 SPECIAL FUNCTION REGISTERS SUMMARY BANK 3
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Page
xxxx xxxx
37,217
30,218
Bank 3
180h
INDF
Addressing this location uses contents of FSR to address data memory (not a physical register)
181h
OPTION_REG
182h
PCL
183h
STATUS
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
0000 0000
37,217
TO
PD
Z
DC
C
0001 1xxx
29,217
Program Counter’s (PC) Least Significant Byte
184h
FSR
185h
SRCON
186h
TRISB
187h
BAUDCTL
188h
ANSEL
189h
IRP
RP1
RP0
Indirect Data Memory Address Pointer
xxxx xxxx
37,217
SR1
SR0
C1SEN
C2REN
PULSS
PULSR
—
FVREN
0000 00-0
93,219
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111
48,218
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
01-0 0-00
162,219
ANS7(2)
ANS6(2)
ANS5(2)
ANS4
ANS3
ANS2
ANS1
ANS0
1111 1111
40,219
ANSELH
—
—
ANS13
ANS12
ANS11
ANS10
ANS9
ANS8
--11 1111
99,219
18Ah
PCLATH
—
—
—
18Bh
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
EEPGD
—
—
—
WRERR
WREN
WR
18Ch
EECON1
18Dh
EECON2
Legend:
Note 1:
2:
Write Buffer for the upper 5 bits of the Program Counter
EEPROM Control Register 2 (not a physical register)
---0 0000
37,217
RBIF(1)
0000 000x
31,217
RD
x--- x000
113,219
---- ----
111,219
– = Unimplemented locations read as ‘0’, u = unchanged, x = unknown, q = value depends on condition, shaded = unimplemented
MCLR and WDT Reset does not affect the previous value data latch. The RBIF bit will be cleared upon Reset but will set again if the
mismatch exists.
PIC16F884/PIC16F887 only.
DS41291F-page 28
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.2.2.1
STATUS Register
The STATUS register, shown in Register 2-1, contains:
• the arithmetic status of the ALU
• the Reset status
• the bank select bits for data memory (GPR and
SFR)
The STATUS register can be the destination for any
instruction, like any other register. If the STATUS
register is the destination for an instruction that affects
the Z, DC or C bits, then the write to these three bits is
disabled. These bits are set or cleared according to the
device logic. Furthermore, the TO and PD bits are not
writable. Therefore, the result of an instruction with the
STATUS register as destination may be different than
intended.
REGISTER 2-1:
R/W-0
It is recommended, therefore, that only BCF, BSF,
SWAPF and MOVWF instructions are used to alter the
STATUS register, because these instructions do not
affect any Status bits. For other instructions not affecting any Status bits, see Section 15.0 “Instruction Set
Summary”
Note 1: The C and DC bits operate as a Borrow
and Digit Borrow out bit, respectively, in
subtraction.
STATUS: STATUS REGISTER
R/W-0
IRP
For example, CLRF STATUS, will clear the upper three
bits and set the Z bit. This leaves the STATUS register
as ‘000u u1uu’ (where u = unchanged).
RP1
R/W-0
RP0
R-1
TO
R-1
PD
R/W-x
R/W-x
R/W-x
Z
DC(1)
C(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
IRP: Register Bank Select bit (used for indirect addressing)
1 = Bank 2, 3 (100h-1FFh)
0 = Bank 0, 1 (00h-FFh)
bit 6-5
RP<1:0>: Register Bank Select bits (used for direct addressing)
00 = Bank 0 (00h-7Fh)
01 = Bank 1 (80h-FFh)
10 = Bank 2 (100h-17Fh)
11 = Bank 3 (180h-1FFh)
bit 4
TO: Time-out bit
1 = After power-up, CLRWDT instruction or SLEEP instruction
0 = A WDT time-out occurred
bit 3
PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
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.
© 2009 Microchip Technology Inc.
DS41291F-page 29
PIC16F882/883/884/886/887
2.2.2.2
OPTION Register
Note:
The OPTION register, shown in Register 2-2, is a
readable and writable register, which contains various
control bits to configure:
•
•
•
•
To achieve a 1:1 prescaler assignment for
Timer0, assign the prescaler to the WDT by
setting PSA bit of the OPTION register to
‘1’. See Section 6.3 “Timer1 Prescaler”.
Timer0/WDT prescaler
External INT interrupt
Timer0
Weak pull-ups on PORTB
REGISTER 2-2:
OPTION_REG: OPTION 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
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
RBPU: PORTB Pull-up Enable bit
1 = PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual PORT latch values
bit 6
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of INT pin
0 = Interrupt on falling edge of INT pin
bit 5
T0CS: Timer0 Clock Source Select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (FOSC/4)
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: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
bit 2-0
PS<2:0>: Prescaler Rate Select bits
DS41291F-page 30
Bit Value
Timer0 Rate
WDT Rate
000
001
010
011
100
101
110
111
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1:1
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
x = Bit is unknown
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.2.2.3
INTCON Register
Note:
The INTCON register, shown in Register 2-3, is a
readable and writable register, which contains the various
enable and flag bits for TMR0 register overflow, PORTB
change and external INT pin interrupts.
REGISTER 2-3:
Interrupt flag bits are set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the Global
Enable bit, GIE of the INTCON register.
User software should ensure the
appropriate interrupt flag bits are clear
prior to enabling an interrupt.
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
PEIE
T0IE
INTE
RBIE(1)
T0IF(2)
INTF
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: Global Interrupt Enable bit
1 = Enables all unmasked interrupts
0 = Disables all interrupts
bit 6
PEIE: Peripheral Interrupt Enable bit
1 = Enables all unmasked peripheral interrupts
0 = Disables all peripheral interrupts
bit 5
T0IE: Timer0 Overflow Interrupt Enable bit
1 = Enables the Timer0 interrupt
0 = Disables the Timer0 interrupt
bit 4
INTE: INT External Interrupt Enable bit
1 = Enables the INT external interrupt
0 = Disables the INT external interrupt
bit 3
RBIE: PORTB Change Interrupt Enable bit(1)
1 = Enables the PORTB change interrupt
0 = Disables the PORTB change interrupt
bit 2
T0IF: Timer0 Overflow Interrupt Flag bit(2)
1 = TMR0 register has overflowed (must be cleared in software)
0 = TMR0 register did not overflow
bit 1
INTF: INT External Interrupt Flag bit
1 = The INT external interrupt occurred (must be cleared in software)
0 = The INT external interrupt did not occur
bit 0
RBIF: PORTB Change Interrupt Flag bit
1 = When at least one of the PORTB general purpose I/O pins changed state (must be cleared in
software)
0 = None of the PORTB general purpose I/O pins have changed state
Note 1:
2:
IOCB register must also be enabled.
T0IF bit is set when Timer0 rolls over. Timer0 is unchanged on Reset and should be initialized before
clearing T0IF bit.
© 2009 Microchip Technology Inc.
DS41291F-page 31
PIC16F882/883/884/886/887
2.2.2.4
PIE1 Register
The PIE1 register contains the interrupt enable bits, as
shown in Register 2-4.
REGISTER 2-4:
Note:
Bit PEIE of the INTCON register must be
set to enable any peripheral interrupt.
PIE1: PERIPHERAL INTERRUPT ENABLE 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
RCIE
TXIE
SSPIE
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 (ADC) Interrupt Enable bit
1 = Enables the ADC interrupt
0 = Disables the ADC interrupt
bit 5
RCIE: EUSART Receive Interrupt Enable bit
1 = Enables the EUSART receive interrupt
0 = Disables the EUSART receive interrupt
bit 4
TXIE: EUSART Transmit Interrupt Enable bit
1 = Enables the EUSART transmit interrupt
0 = Disables the EUSART transmit interrupt
bit 3
SSPIE: Master Synchronous Serial Port (MSSP) Interrupt Enable bit
1 = Enables the MSSP interrupt
0 = Disables the MSSP interrupt
bit 2
CCP1IE: CCP1 Interrupt Enable bit
1 = Enables the CCP1 interrupt
0 = Disables the CCP1 interrupt
bit 1
TMR2IE: Timer2 to PR2 Match Interrupt Enable bit
1 = Enables the Timer2 to PR2 match interrupt
0 = Disables the Timer2 to PR2 match interrupt
bit 0
TMR1IE: Timer1 Overflow Interrupt Enable bit
1 = Enables the Timer1 overflow interrupt
0 = Disables the Timer1 overflow interrupt
DS41291F-page 32
x = Bit is unknown
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.2.2.5
PIE2 Register
The PIE2 register contains the interrupt enable bits, as
shown in Register 2-5.
REGISTER 2-5:
Note:
Bit PEIE of the INTCON register must be
set to enable any peripheral interrupt.
PIE2: PERIPHERAL INTERRUPT ENABLE REGISTER 2
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
U-0
R/W-0
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
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
OSFIE: Oscillator Fail Interrupt Enable bit
1 = Enables oscillator fail interrupt
0 = Disables oscillator fail interrupt
bit 6
C2IE: Comparator C2 Interrupt Enable bit
1 = Enables Comparator C2 interrupt
0 = Disables Comparator C2 interrupt
bit 5
C1IE: Comparator C1 Interrupt Enable bit
1 = Enables Comparator C1 interrupt
0 = Disables Comparator C1 interrupt
bit 4
EEIE: EEPROM Write Operation Interrupt Enable bit
1 = Enables EEPROM write operation interrupt
0 = Disables EEPROM write operation interrupt
bit 3
BCLIE: Bus Collision Interrupt Enable bit
1 = Enables Bus Collision interrupt
0 = Disables Bus Collision interrupt
bit 2
ULPWUIE: Ultra Low-Power Wake-up Interrupt Enable bit
1 = Enables Ultra Low-Power Wake-up interrupt
0 = Disables Ultra Low-Power Wake-up interrupt
bit 1
Unimplemented: Read as ‘0’
bit 0
CCP2IE: CCP2 Interrupt Enable bit
1 = Enables CCP2 interrupt
0 = Disables CCP2 interrupt
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS41291F-page 33
PIC16F882/883/884/886/887
2.2.2.6
PIR1 Register
The PIR1 register contains the interrupt flag bits, as
shown in Register 2-6.
REGISTER 2-6:
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, GIE of the INTCON register.
User software should ensure the
appropriate interrupt flag bits are clear prior
to enabling an interrupt.
PIR1: PERIPHERAL INTERRUPT REQUEST REGISTER 1
U-0
R/W-0
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIF
RCIF
TXIF
SSPIF
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 = A/D conversion complete (must be cleared in software)
0 = A/D conversion has not completed or has not been started
bit 5
RCIF: EUSART Receive Interrupt Flag bit
1 = The EUSART receive buffer is full (cleared by reading RCREG)
0 = The EUSART receive buffer is not full
bit 4
TXIF: EUSART Transmit Interrupt Flag bit
1 = The EUSART transmit buffer is empty (cleared by writing to TXREG)
0 = The EUSART transmit buffer is full
bit 3
SSPIF: Master Synchronous Serial Port (MSSP) Interrupt Flag bit
1 = The MSSP interrupt condition has occurred, and must be cleared in software before returning from the
Interrupt Service Routine. The conditions that will set this bit are:
SPI
A transmission/reception has taken place
I2 C Slave/Master
A transmission/reception has taken place
I2 C Master
The initiated Start condition was completed by the MSSP module
The initiated Stop condition was completed by the MSSP module
The initiated restart condition was completed by the MSSP module
The initiated Acknowledge condition was completed by the MSSP module
A Start condition occurred while the MSSP module was idle (Multi-master system)
A Stop condition occurred while the MSSP module was idle (Multi-master system)
0 = No MSSP interrupt condition has occurred
bit 2
CCP1IF: CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode
bit 1
TMR2IF: Timer2 to PR2 Interrupt Flag bit
1 = A Timer2 to PR2 match occurred (must be cleared in software)
0 = No Timer2 to PR2 match occurred
bit 0
TMR1IF: Timer1 Overflow Interrupt Flag bit
1 = The TMR1 register overflowed (must be cleared in software)
0 = The TMR1 register did not overflow
DS41291F-page 34
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.2.2.7
PIR2 Register
The PIR2 register contains the interrupt flag bits, as
shown in Register 2-7.
REGISTER 2-7:
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, GIE of the INTCON register.
User software should ensure the
appropriate interrupt flag bits are clear prior
to enabling an interrupt.
PIR2: PERIPHERAL INTERRUPT REQUEST REGISTER 2
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
U-0
R/W-0
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
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
OSFIF: Oscillator Fail Interrupt Flag bit
1 = System oscillator failed, clock input has changed to INTOSC (must be cleared in software)
0 = System clock operating
bit 6
C2IF: Comparator C2 Interrupt Flag bit
1 = Comparator output (C2OUT bit) has changed (must be cleared in software)
0 = Comparator output (C2OUT bit) has not changed
bit 5
C1IF: Comparator C1 Interrupt Flag bit
1 = Comparator output (C1OUT bit) has changed (must be cleared in software)
0 = Comparator output (C1OUT bit) has not changed
bit 4
EEIF: EE Write Operation Interrupt Flag bit
1 = Write operation completed (must be cleared in software)
0 = Write operation has not completed or has not started
bit 3
BCLIF: Bus Collision Interrupt Flag bit
1 = A bus collision has occurred in the MSSP when configured for I2C Master mode
0 = No bus collision has occurred
bit 2
ULPWUIF: Ultra Low-Power Wake-up Interrupt Flag bit
1 = Wake-up condition has occurred (must be cleared in software)
0 = No Wake-up condition has occurred
bit 1
Unimplemented: Read as ‘0’
bit 0
CCP2IF: CCP2 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode
© 2009 Microchip Technology Inc.
DS41291F-page 35
PIC16F882/883/884/886/887
2.2.2.8
PCON Register
The Power Control (PCON) register (see Register 2-8)
contains flag bits to differentiate between a:
•
•
•
•
Power-on Reset (POR)
Brown-out Reset (BOR)
Watchdog Timer Reset (WDT)
External MCLR Reset
The PCON register also controls the Ultra Low-Power
Wake-up and software enable of the BOR.
REGISTER 2-8:
PCON: POWER CONTROL REGISTER
U-0
U-0
R/W-0
R/W-1
U-0
U-0
R/W-0
R/W-x
—
—
ULPWUE
SBOREN(1)
—
—
POR
BOR
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
Unimplemented: Read as ‘0’
bit 5
ULPWUE: Ultra Low-Power Wake-up Enable bit
1 = Ultra Low-Power Wake-up enabled
0 = Ultra Low-Power Wake-up disabled
bit 4
SBOREN: Software BOR Enable bit(1)
1 = BOR enabled
0 = BOR disabled
bit 3-2
Unimplemented: Read as ‘0’
bit 1
POR: Power-on Reset Status bit
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
1 = No Brown-out Reset occurred
0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs)
Note 1:
BOREN<1:0> = 01 in the Configuration Word Register 1 for this bit to control the BOR.
DS41291F-page 36
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
2.3
2.3.2
PCL and PCLATH
The Program Counter (PC) is 13 bits wide. The low byte
comes from the PCL register, which is a readable and
writable register. The high byte (PC<12:8>) is not directly
readable or writable and comes from PCLATH. On any
Reset, the PC is cleared. Figure 2-7 shows the two
situations for the loading of the PC. The upper example
in Figure 2-7 shows how the PC is loaded on a write to
PCL (PCLATH<4:0> → PCH). The lower example in
Figure 2-7 shows how the PC is loaded during a CALL or
GOTO instruction (PCLATH<4:3> → PCH).
FIGURE 2-7:
LOADING OF PC IN
DIFFERENT SITUATIONS
PCH
PCL
12
8
7
0
PC
The PIC16F882/883/884/886/887 devices have an
8-level x 13-bit wide hardware stack (see Figures 2-2
and 2-3). The stack space is not part of either program
or data space and the Stack Pointer is not readable or
writable. The PC is PUSHed onto the stack when a
CALL instruction is executed or an interrupt causes a
branch. The stack is POPed in the event of a RETURN,
RETLW or a RETFIE instruction execution. PCLATH is
not affected by a PUSH or POP operation.
The stack operates as a circular buffer. This means that
after the stack has been PUSHed eight times, the ninth
push overwrites the value that was stored from the first
push. The tenth push overwrites the second push (and
so on).
Note 1: There are no Status bits to indicate stack
overflow or stack underflow conditions.
2: There are no instructions/mnemonics
called PUSH or POP. These are actions
that occur from the execution of the
CALL, RETURN, RETLW and RETFIE
instructions or the vectoring to an
interrupt address.
8
PCLATH<4:0>
5
Instruction with
PCL as
Destination
ALU Result
PCLATH
PCH
12
11 10
PCL
8
0
7
PC
GOTO, CALL
2
PCLATH<4:3>
11
OPCODE<10:0>
PCLATH
2.3.1
STACK
MODIFYING PCL
Executing any instruction with the PCL register as the
destination simultaneously causes the Program
Counter PC<12:8> bits (PCH) to be replaced by the
contents of the PCLATH register. This allows the entire
contents of the program counter to be changed by
writing the desired upper 5 bits to the PCLATH register.
When the lower 8 bits are written to the PCL register, all
13 bits of the program counter will change to the values
contained in the PCLATH register and those being
written to the PCL register.
A computed GOTO is accomplished by adding an offset
to the program counter (ADDWF PCL). Care should be
exercised when jumping into a look-up table or
program branch table (computed GOTO) by modifying
the PCL register. Assuming that PCLATH is set to the
table start address, if the table length is greater than
255 instructions or if the lower 8 bits of the memory
address rolls over from 0xFF to 0x00 in the middle of
the table, then PCLATH must be incremented for each
address rollover that occurs between the table
beginning and the target location within the table.
2.4
Indirect Addressing, INDF and
FSR Registers
The INDF register is not a physical register. Addressing
the INDF register will cause indirect addressing.
Indirect addressing is possible by using the INDF
register. Any instruction using the INDF register actually
accesses data pointed to by the File Select Register
(FSR). Reading INDF itself indirectly will produce 00h.
Writing to the INDF register indirectly results in a no
operation (although Status bits may be affected). An
effective 9-bit address is obtained by concatenating the
8-bit FSR and the IRP bit of the STATUS register, as
shown in Figure 2-8.
A simple program to clear RAM location 20h-2Fh using
indirect addressing is shown in Example 2-1.
EXAMPLE 2-1:
MOVLW
MOVWF
NEXT
CLRF
INCF
BTFSS
GOTO
CONTINUE
INDIRECT ADDRESSING
0x20
FSR
INDF
FSR
FSR,4
NEXT
;initialize pointer
;to RAM
;clear INDF register
;inc pointer
;all done?
;no clear next
;yes continue
For more information refer to Application Note AN556,
“Implementing a Table Read” (DS00556).
© 2009 Microchip Technology Inc.
DS41291F-page 37
PIC16F882/883/884/886/887
FIGURE 2-8:
DIRECT/INDIRECT ADDRESSING PIC16F882/883/884/886/887
Direct Addressing
RP1 RP0
6
Bank Select
From Opcode
Indirect Addressing
0
IRP
7
Bank Select
Location Select
00
01
10
File Select Register
0
Location Select
11
00h
180h
Data
Memory
7Fh
1FFh
Bank 0
Note:
DS41291F-page 38
Bank 1
Bank 2
Bank 3
For memory map detail, see Figures 2-2 and 2-3.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.0
I/O PORTS
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then
written to the PORT data latch.
There are as many as thirty-five general purpose I/O
pins available. Depending on which peripherals are
enabled, some or all of the pins may not be available as
general purpose I/O. In general, when a peripheral is
enabled, the associated pin may not be used as a
general purpose I/O pin.
3.1
The TRISA register (Register 3-2) controls the PORTA
pin output drivers, 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. I/O pins configured as analog input always
read ‘0’.
PORTA and the TRISA Registers
Note:
PORTA is a 8-bit wide, bidirectional port. The
corresponding data direction register is TRISA
(Register 3-2). 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., enables
output driver and puts the contents of the output latch
on the selected pin). Example 3-1 shows how to
initialize PORTA.
EXAMPLE 3-1:
BANKSEL
CLRF
BANKSEL
CLRF
BANKSEL
MOVLW
MOVWF
Reading the PORTA register (Register 3-1) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
REGISTER 3-1:
The ANSEL register must be initialized to
configure an analog channel as a digital
input. Pins configured as analog inputs will
read ‘0’.
PORTA
PORTA
ANSEL
ANSEL
TRISA
0Ch
TRISA
INITIALIZING PORTA
;
;Init PORTA
;
;digital I/O
;
;Set RA<3:2> as inputs
;and set RA<5:4,1:0>
;as outputs
PORTA: PORTA REGISTER
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
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
RA<7:0>: PORTA I/O Pin bit
1 = Port pin is > VIH
0 = Port pin is < VIL
REGISTER 3-2:
TRISA: PORTA TRI-STATE REGISTER
R/W-1(1)
R/W-1(1)
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
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
TRISA<7:0>: PORTA Tri-State Control bit
1 = PORTA pin configured as an input (tri-stated)
0 = PORTA pin configured as an output
TRISA<7:6> always reads ‘1’ in XT, HS and LP Oscillator modes.
© 2009 Microchip Technology Inc.
DS41291F-page 39
PIC16F882/883/884/886/887
3.2
Additional Pin Functions
RA0 also has an Ultra Low-Power Wake-up option. The
next three sections describe these functions.
3.2.1
ANSEL REGISTER
The ANSEL register (Register 3-3) is used to configure
the Input mode of an I/O pin to analog. Setting the
appropriate ANSEL bit high will cause all digital reads
on the pin to be read as ‘0’ and allow analog functions
on the pin to operate correctly.
The state of the ANSEL bits has no affect on digital output functions. A pin with TRIS clear and ANSEL set will
still operate as a digital output, but the Input mode will
be analog. This can cause unexpected behavior when
executing read-modify-write instructions on the
affected port.
REGISTER 3-3:
ANSEL: 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
ANS7(2)
ANS6(2)
ANS5(2)
ANS4
ANS3
ANS2
ANS1
ANS0
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
ANS<7:0>: Analog Select bits
Analog select between analog or digital function on pins AN<7:0>, respectively.
1 = Analog input. Pin is assigned as analog input(1).
0 = Digital I/O. Pin is assigned to port or special function.
Note 1:
2:
Setting a pin to an analog input automatically disables the digital input circuitry, weak pull-ups, and
interrupt-on-change if available. The corresponding TRIS bit must be set to Input mode in order to allow
external control of the voltage on the pin.
Not implemented on PIC16F883/886.
DS41291F-page 40
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.2.2
ULTRA LOW-POWER WAKE-UP
The Ultra Low-Power Wake-up (ULPWU) on RA0 allows
a slow falling voltage to generate an interrupt-on-change
on RA0 without excess current consumption. The mode
is selected by setting the ULPWUE bit of the PCON
register. This enables a small current sink, which can be
used to discharge a capacitor on RA0.
Follow these steps to use this feature:
a)
b)
c)
d)
e)
Charge the capacitor on RA0 by configuring the
RA0 pin to output (= 1).
Configure RA0 as an input.
Set the ULPWUIE bit of the PIE2 register to
enable interrupt.
Set the ULPWUE bit of the PCON register to
begin the capacitor discharge.
Execute a SLEEP instruction.
When the voltage on RA0 drops below VIL, an interrupt
will be generated which will cause the device to
wake-up and execute the next instruction. If the GIE bit
of the INTCON register is set, the device will then call
the interrupt vector (0004h).
This feature provides a low-power technique for
periodically waking up the device from Sleep. The
time-out is dependent on the discharge time of the RC
circuit on RA0. See Example 3-2 for initializing the
Ultra Low-Power Wake-up module.
© 2009 Microchip Technology Inc.
A series resistor between RA0 and the external
capacitor provides overcurrent protection for the
RA0/AN0/ULPWU/C12IN0- pin and can allow for
software calibration of the time-out (see Figure 3-1). A
timer can be used to measure the charge time and
discharge time of the capacitor. The charge time can
then be adjusted to provide the desired interrupt delay.
This technique will compensate for the affects of
temperature, voltage and component accuracy. The
Ultra Low-Power Wake-up peripheral can also be
configured as a simple Programmable Low Voltage
Detect or temperature sensor.
Note:
For more information, refer to AN879,
“Using the Microchip Ultra Low-Power
Wake-up Module” Application Note
(DS00879).
EXAMPLE 3-2:
BANKSEL
BSF
BANKSEL
BCF
BANKSEL
BCF
CALL
BANKSEL
BCF
BANKSEL
BSF
BSF
BSF
MOVLW
MOVWF
SLEEP
NOP
ULTRA LOW-POWER
WAKE-UP INITIALIZATION
PORTA
PORTA,0
ANSEL
ANSEL,0
TRISA
TRISA,0
CapDelay
PIR2
PIR2,ULPWUIF
PCON
PCON,ULPWUE
TRISA,0
PIE2, ULPWUIE
B’11000000’
INTCON
;
;Set RA0 data latch
;
;RA0 to digital I/O
;
;Output high to
;charge capacitor
;
;Clear flag
;Enable ULP Wake-up
;RA0 to input
;Enable interrupt
;Enable peripheral
;interrupt
;Wait for IOC
;
DS41291F-page 41
PIC16F882/883/884/886/887
3.2.3
PIN DESCRIPTIONS AND
DIAGRAMS
3.2.3.1
Each PORTA pin is multiplexed with other functions. The
pins and their combined functions are briefly described
here. For specific information about individual functions
such as the comparator or the A/D Converter (ADC),
refer to the appropriate section in this data sheet.
FIGURE 3-1:
RA0/AN0/ULPWU/C12IN0-
Figure 3-1 shows the diagram for this pin. This pin is
configurable to function as one of the following:
•
•
•
•
a general purpose I/O
an analog input for the ADC
a negative analog input to Comparator C1 or C2
an analog input for the Ultra Low-Power Wake-up
BLOCK DIAGRAM OF RA0
VDD
Data Bus
D
WR
PORTA
Q
I/O Pin
CK Q
VSS
+
D
WR
TRISA
CK Q
IULP
0
RD
TRISA
VTRG
Q
Analog(1)
Input Mode
1
VSS
ULPWUE
RD
PORTA
To Comparator
To A/D Converter
Note
DS41291F-page 42
1:
ANSEL determines Analog Input mode.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.2.3.2
3.2.3.3
RA1/AN1/C12IN1-
RA2/AN2/VREF-/CVREF/C2IN+
Figure 3-2 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-3 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
• a negative analog input to Comparator C1 or C2
• a general purpose I/O
• an analog input for the ADC
• a negative voltage reference input for the ADC
and CVREF
• a comparator voltage reference output
• a positive analog input to Comparator C2
FIGURE 3-2:
BLOCK DIAGRAM OF RA1
Data Bus
D
WR
PORTA
CK
FIGURE 3-3:
VDD
Q
Data Bus
Q
VROE
D
I/O Pin
D
WR
TRISA
Q
CK
WR
PORTA
Q
CK
VDD
Q
I/O Pin
D
WR
TRISA
RD
PORTA
Q
CK
Q
To Comparator
To A/D Converter
VSS
Analog(1)
Input Mode
RD
TRISA
1:
CVREF
Q
VSS
Analog(1)
Input Mode
RD
TRISA
Note
BLOCK DIAGRAM OF RA2
RD
PORTA
ANSEL determines Analog Input mode.
To Comparator (positive input)
To Comparator (VREF-)
To A/D Converter (VREF-)
To A/D Converter (analog channel)
Note
© 2009 Microchip Technology Inc.
1:
ANSEL determines Analog Input mode.
DS41291F-page 43
PIC16F882/883/884/886/887
3.2.3.4
RA3/AN3/VREF+/C1IN+
3.2.3.5
RA4/T0CKI/C1OUT
Figure 3-4 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-5 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose input
• an analog input for the ADC
• a positive voltage reference input for the ADC and
CVREF
• a positive analog input to Comparator C1
• a general purpose I/O
• a clock input for Timer0
• a digital output from Comparator C1
FIGURE 3-4:
BLOCK DIAGRAM OF RA3
FIGURE 3-5:
Data Bus
C1OUT
Enable
D
Data Bus
D
WR
PORTA
CK
WR
PORTA
VDD
Q
WR
TRISA
D
Q
CK
Q
VSS
Analog(1)
Input Mode
RD
TRISA
CK
VDD
Q
Q
C1OUT
1
0
Q
I/O Pin
D
BLOCK DIAGRAM OF RA4
WR
TRISA
CK
I/O Pin
Q
Q
VSS
RD
TRISA
RD
PORTA
RD
PORTA
To Timer0
To Comparator (positive input)
To Comparator (VREF+)
To A/D Converter (VREF+)
To A/D Converter (analog channel)
Note
1:
ANSEL determines Analog Input mode.
DS41291F-page 44
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.2.3.6
3.2.3.7
RA5/AN4/SS/C2OUT
RA6/OSC2/CLKOUT
Figure 3-6 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-7 shows the diagram for this pin. This pin is
configurable to function as one of the following:
•
•
•
•
• a general purpose I/O
• a crystal/resonator connection
• a clock output
a general purpose I/O
an analog input for the ADC
a slave select input
a digital output from Comparator C2
FIGURE 3-7:
FIGURE 3-6:
BLOCK DIAGRAM OF RA6
BLOCK DIAGRAM OF RA5
Oscillator
Circuit
Data Bus
Data Bus
OSC2
C2OUT
Enable
D
WR
PORTA
Q
CK
Q
C2OUT
D
1
0
D
WR
TRISA
CLKOUT
Enable
VDD
I/O Pin
WR
PORTA
CK
Q
1
0
I/O Pin
Q
CLKOUT
Enable
Q
CK
FOSC/4
VDD
VSS
Q
Analog(1)
Input Mode
RD
TRISA
D
VSS
WR
TRISA
CK
Q
Q
RD
TRISA
RD
PORTA
INTOSCIO/
EXTRCIO/EC(1)
CLKOUT
Enable
RD
PORTA
To SS Input
To A/D Converter
Note
1:
ANSEL determines Analog Input mode.
© 2009 Microchip Technology Inc.
Note 1: With I/O option.
DS41291F-page 45
PIC16F882/883/884/886/887
3.2.3.8
RA7/OSC1/CLKIN
Figure 3-8 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a crystal/resonator connection
• a clock input
FIGURE 3-8:
BLOCK DIAGRAM OF RA7
Oscillator
Circuit
Data Bus
OSC1
D
WR
PORTA
VDD
Q
CK Q
I/O Pin
D
WR
TRISA
Q
CK Q
VSS
INTOSC
Mode
RD
TRISA
RD
PORTA
CLKIN
TABLE 3-1:
Name
ADCON0
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
ADCS1
ADCS0
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
0000 0000
0000 0000
ANSEL
ANS7
ANS6
ANS5
ANS4
ANS3
ANS2
ANS1
ANS0
1111 1111
1111 1111
CM1CON0
C1ON
C1OUT
C1OE
C1POL
—
C1R
C1CH1
C1CH0
0000 -000
0000 -000
CM2CON0
C2ON
C2OUT
C2OE
C2POL
—
C2R
C2CH1
C2CH0
0000 -000
0000 -000
CM2CON1
MC1OUT
MC2OUT
C1RSEL
C2RSEL
—
—
T1GSS
C2SYNC
0000 --10
0000 --10
PCON
OPTION_REG
PORTA
SSPCON
TRISA
Legend:
—
—
ULPWUE
SBOREN
—
—
POR
BOR
--01 --qq
--0u --uu
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
xxxx xxxx
uuuu uuuu
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
0000 0000
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
1111 1111
x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by PORTA.
DS41291F-page 46
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.3
PORTB and TRISB Registers
PORTB is an 8-bit wide, bidirectional port. The
corresponding data direction register is TRISB
(Register 3-6). Setting a TRISB bit (= 1) will make the
corresponding PORTB pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
Clearing a TRISB bit (= 0) will make the corresponding
PORTB pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
Example 3-3 shows how to initialize PORTB.
Reading the PORTB register (Register 3-5) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then written
to the PORT data latch.
The TRISB register (Register 3-6) controls the PORTB
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISB register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’. Example 3-3 shows how to initialize PORTB.
EXAMPLE 3-3:
BANKSEL
CLRF
BANKSEL
MOVLW
MOVWF
Note:
3.4
INITIALIZING PORTB
PORTB
;
PORTB
;Init PORTB
TRISB
;
B‘11110000’ ;Set RB<7:4> as inputs
;and RB<3:0> as outputs
TRISB
;
The ANSELH register must be initialized
to configure an analog channel as a digital
input. Pins configured as analog inputs will
read ‘0’.
Additional PORTB Pin Functions
PORTB pins RB<7:0> on the device family device have
an interrupt-on-change option and a weak pull-up
option. The following three sections describe these
PORTB pin functions.
Every PORTB pin on this device family has an
interrupt-on-change option and a weak pull-up option.
3.4.1
The ANSELH register (Register 3-4) is used to
configure the Input mode of an I/O pin to analog.
Setting the appropriate ANSELH bit high will cause all
digital reads on the pin to be read as ‘0’ and allow
analog functions on the pin to operate correctly.
The state of the ANSELH bits has no affect on digital
output functions. A pin with TRIS clear and ANSELH
set will still operate as a digital output, but the Input
mode will be analog. This can cause unexpected
behavior
when
executing
read-modify-write
instructions on the affected port.
3.4.2
WEAK PULL-UPS
Each of the PORTB pins has an individually configurable
internal weak pull-up. Control bits WPUB<7:0> enable or
disable each pull-up (see Register 3-7). Each weak
pull-up is automatically turned off when the port pin is
configured as an output. All pull-ups are disabled on a
Power-on Reset by the RBPU bit of the OPTION register.
3.4.3
INTERRUPT-ON-CHANGE
All of the PORTB pins are individually configurable as an
interrupt-on-change pin. Control bits IOCB<7:0> enable
or disable the interrupt function for each pin. Refer to
Register 3-8. The interrupt-on-change feature is
disabled on a Power-on Reset.
For enabled interrupt-on-change pins, the present value
is compared with the old value latched on the last read
of PORTB to determine which bits have changed or
mismatched the old value. 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 Sleep. The user,
in the Interrupt Service Routine, clears the interrupt by:
a)
b)
Any read or write of PORTB. This will end the
mismatch condition.
Clear the flag bit RBIF.
A mismatch condition will continue to set flag bit RBIF.
Reading or writing PORTB will end the mismatch
condition and allow flag bit RBIF to be cleared. The latch
holding the last read value is not affected by a MCLR nor
Brown-out Reset. After these Resets, the RBIF flag will
continue to be set if a mismatch is present.
Note:
© 2009 Microchip Technology Inc.
ANSELH REGISTER
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.
DS41291F-page 47
PIC16F882/883/884/886/887
REGISTER 3-4:
ANSELH: ANALOG SELECT HIGH REGISTER
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
—
—
ANS13
ANS12
ANS11
ANS10
ANS9
ANS8
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
Unimplemented: Read as ‘0’
bit 5-0
ANS<13:8>: Analog Select bits
Analog select between analog or digital function on pins AN<13:8>, respectively.
1 = Analog input. Pin is assigned as analog input(1).
0 = Digital I/O. Pin is assigned to port or special function.
Note 1:
Setting a pin to an analog input automatically disables the digital input circuitry, weak pull-ups, and
interrupt-on-change if available. The corresponding TRIS bit must be set to Input mode in order to allow
external control of the voltage on the pin.
REGISTER 3-5:
PORTB: PORTB REGISTER
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
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
RB<7:0>: PORTB I/O Pin bit
1 = Port pin is > VIH
0 = Port pin is < VIL
REGISTER 3-6:
TRISB: PORTB TRI-STATE 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
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
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
TRISB<7:0>: PORTB Tri-State Control bit
1 = PORTB pin configured as an input (tri-stated)
0 = PORTB pin configured as an output
DS41291F-page 48
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 3-7:
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 bit
1 = Pull-up enabled
0 = Pull-up disabled
Note 1: Global RBPU bit of the OPTION register must be cleared for individual pull-ups to be enabled.
2: The weak pull-up device is automatically disabled if the pin is in configured as an output.
REGISTER 3-8:
IOCB: INTERRUPT-ON-CHANGE PORTB REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
IOCB7
IOCB6
IOCB5
IOCB4
IOCB3
IOCB2
IOCB1
IOCB0
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
IOCB<7:0>: Interrupt-on-Change PORTB Control bit
1 = Interrupt-on-change enabled
0 = Interrupt-on-change disabled
© 2009 Microchip Technology Inc.
DS41291F-page 49
PIC16F882/883/884/886/887
3.4.4
PIN DESCRIPTIONS AND
DIAGRAMS
Each PORTB pin is multiplexed with other functions. The
pins and their combined functions are briefly described
here. For specific information about individual functions
such as the SSP, I2C or interrupts, refer to the appropriate
section in this data sheet.
3.4.4.1
FIGURE 3-9:
Data Bus
D
WR
WPUB
BLOCK DIAGRAM OF
RB<3:0>
Q
CK
RBPU
CCP1OUT Enable
D
WR
PORTB
Note 1: P1C is available on PIC16F882/883/886
only.
RB2/AN8/P1B(1)
Figure 3-9 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
• a PWM output(1)
D
WR
TRISB
CK
Q
VSS
Analog(1)
Input Mode
D
Q
Q
CK Q
WR
IOCB
D
EN
RD
IOCB
Q
Q3
D
EN
Interrupt-onChange
RD PORTB
RB0/INT
RB3/PGM
To A/D Converter
Figure 3-9 shows the diagram for this pin. This pin is
configurable to function as one of the following:
DS41291F-page 50
Q
RD
PORTB
RB3/AN9/PGM/C12IN2-
• a general purpose I/O
• an analog input for the ADC
• Low-voltage In-Circuit Serial Programming enable
pin
• an analog input to Comparator C1 or C2
Q
RD
TRISB
Note 1: P1B is available on PIC16F882/883/886
only.
3.4.4.4
CK
VDD
CCP1OUT 1
I/O Pin
RB1/AN10/P1C /C12IN3-
a general purpose I/O
an analog input for the ADC
a PWM output(1)
an analog input to Comparator C1 or C2
Q
0
(1)
Figure 3-9 shows the diagram for this pin. This pin is
configurable to function as one of the following:
3.4.4.3
Weak
RD
WPUB
RB0/AN12/INT
• a general purpose I/O
• an analog input for the ADC
• an external edge triggered interrupt
•
•
•
•
VDD
Q
Figure 3-9 shows the diagram for this pin. This pin is
configurable to function as one of the following:
3.4.4.2
Analog(1)
Input Mode
To Comparator (RB1, RB3)
Note
1:
ANSELH determines Analog Input mode.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.4.4.5
RB4/AN11/P1D(1)
3.4.4.7
RB6/ICSPCLK
Figure 3-10 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-10 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
• a PWM output(1)
• a general purpose I/O
• In-Circuit Serial Programming clock
3.4.4.8
Note 1: P1D is available on PIC16F882/883/886
only.
3.4.4.6
RB7/ICSPDAT
Figure 3-10 shows the diagram for this pin. This pin is
configurable to function as one of the following:
RB5/AN13/T1G
• a general purpose I/O
• In-Circuit Serial Programming data
Figure 3-10 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
• a Timer1 gate input
FIGURE 3-10:
BLOCK DIAGRAM OF RB<7:4>
Analog(1) Input Mode
VDD
Data Bus
D
WR
WPUB
CK
Q
Weak
Q
RD
WPUB
RBPU
CCP1OUT Enable
VDD
D
WR
PORTB
CK
Q
CCP1OUT
0
11
Q
I/O Pin
00
1
D
WR
TRISB
CK
Q
VSS
Q
RD
TRISB
Analog(1)
Input Mode
RD
PORTB
D
Q
Q
CK
WR
IOCB
ICSP™(2)
D
Q
EN
RD
IOCB
Q
Q3
D
EN
Interrupt-onChange
RD PORTB
To Timer1 T1G(3)
To A/D Converter
To ICSPCLK (RB6) and ICSPDAT (RB7)
Available on PIC16F882/PIC16F883/PIC16F886 only.
Note
1:
2:
3:
ANSELH determines Analog Input mode.
Applies to RB<7:6> pins only).
Applies to RB5 pin only.
© 2009 Microchip Technology Inc.
DS41291F-page 51
PIC16F882/883/884/886/887
TABLE 3-2:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Bit 7
Bit 5
Bit 4
—
—
ANS13
ANS12
P1M1
P1M0
DC1B1
DC1B0
ANSELH
CCP1CON
Bit 6
MC1OUT MC2OUT C1RSEL C2RSEL
CM2CON1
IOCB
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
ANS11
ANS10
ANS9
ANS8
--11 1111 --11 1111
CCP1M3 CCP1M2 CCP1M1 CCP1M0 0000 0000 0000 0000
—
—
T1GSS
IOCB7
IOCB6
IOCB5
IOCB4
IOCB3
IOCB2
IOCB1
IOCB0
0000 0000 0000 0000
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000x
INTCON
OPTION_REG
Value on
all other
Resets
Bit 3
C2SYNC 0000 --10 0000 --10
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111 1111 1111
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx uuuu uuuu
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111 1111 1111
WPUB
WPUB7
WPUB6
WPUB5
WPUB4
WPUB3
WPUB2
WPUB1
WPUB0
1111 1111 1111 1111
Legend:
x = unknown, u = unchanged, — = unimplemented read as ‘0’. Shaded cells are not used by PORTB.
DS41291F-page 52
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.5
PORTC and TRISC Registers
The TRISC register (Register 3-10) controls the PORTC
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISC register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
PORTC is a 8-bit wide, bidirectional port. The
corresponding data direction register is TRISC
(Register 3-10). Setting a TRISC bit (= 1) will make the
corresponding PORTC pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
Clearing a TRISC bit (= 0) will make the corresponding
PORTC pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
Example 3-4 shows how to initialize PORTC.
EXAMPLE 3-4:
BANKSEL
CLRF
BANKSEL
MOVLW
MOVWF
Reading the PORTC register (Register 3-9) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then written
to the PORT data latch.
REGISTER 3-9:
INITIALIZING PORTC
PORTC
PORTC
TRISC
B‘00001100’
TRISC
;
;Init PORTC
;
;Set RC<3:2> as inputs
;and set RC<7:4,1:0>
;as outputs
PORTC: PORTC REGISTER
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
RC7
RC6
RC5
RC4
RC3
RC2
RC1
RC0
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
RC<7:0>: PORTC General Purpose I/O Pin bit
1 = Port pin is > VIH
0 = Port pin is < VIL
REGISTER 3-10:
TRISC: PORTC TRI-STATE REGISTER
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1(1)
R/W-1(1)
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
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
TRISC<7:0>: PORTC Tri-State Control bit
1 = PORTC pin configured as an input (tri-stated)
0 = PORTC pin configured as an output
TRISC<1:0> always reads ‘1’ in LP Oscillator mode.
© 2009 Microchip Technology Inc.
DS41291F-page 53
PIC16F882/883/884/886/887
3.5.1
3.5.3
RC0/T1OSO/T1CKI
RC2/P1A/CCP1
Figure 3-11 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-13 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a Timer1 oscillator output
• a Timer1 clock input
• a general purpose I/O
• a PWM output
• a Capture input and Compare output for
Comparator C1
FIGURE 3-11:
BLOCK DIAGRAM OF RC0
Data Bus
T1OSCEN
D
FIGURE 3-13:
Timer1 Oscillator
Circuit
CCP1CON
VDD
Q
D
WR
PORTC
CK
BLOCK DIAGRAM OF RC2
Data bus
Q
WR
PORTC
CK
VDD
Q
Q
CCP1/P1A
0
1
I/O Pin
D
1
0
Q
D
WR
TRISC
CK
Q
VSS
WR
TRISC
RD
TRISC
CK
I/O Pin
Q
Q
VSS
RD
TRISC
RD
PORTC
RD
PORTC
To Enhanced CCP1
To Timer1 clock input
3.5.2
RC1/T1OSI/CCP2
Figure 3-12 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a Timer1 oscillator input
• a Capture input and Compare/PWM output for
Comparator C2
FIGURE 3-12:
BLOCK DIAGRAM OF RC1
T1OSCEN
T1OSI
Data Bus
Timer1 Oscillator
Circuit
CCP2CON
D
WR
PORTC
CK
VDD
Q
Q
CCP2
0
1
1
0
D
WR
TRISC
CK
I/O Pin
Q
Q
VSS
T1OSCEN
RD
TRISC
RD
PORTC
To CCP2
DS41291F-page 54
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.5.4
RC3/SCK/SCL
3.5.6
RC5/SDO
Figure 3-14 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-16 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a SPI clock
• an I2C™ clock
• a general purpose I/O
• a serial data output
FIGURE 3-16:
FIGURE 3-14:
BLOCK DIAGRAM OF RC5
BLOCK DIAGRAM OF RC3
Data Bus
Port/SDO
Select
Data Bus
SDO
SSPEN
D
WR
PORTC
Q
CK Q
0
1
VDD
D
Q
1
0
VDD
0
1
SCK
WR
PORTC
1
0
I/O Pin
CK Q
I/O Pin
D
WR
TRISC
Q
D
CK Q
WR
TRISC
VSS
RD
TRISC
RD
TRISC
RD
PORTC
RD
PORTC
Q
CK Q
VSS
To SSPSR
3.5.5
RC4/SDI/SDA
Figure 3-15 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a SPI data I/O
• an I2C data I/O
FIGURE 3-15:
BLOCK DIAGRAM OF RC4
Data Bus
SSPEN
D
WR
PORTC
Q
SDI/SDA
VDD
0
1
CK Q
1
0
I/O Pin
D
WR
TRISC
Q
CK Q
VSS
RD
TRISC
RD
PORTC
To SSPSR
© 2009 Microchip Technology Inc.
DS41291F-page 55
PIC16F882/883/884/886/887
3.5.7
3.5.8
RC6/TX/CK
RC7/RX/DT
Figure 3-17 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Figure 3-18 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an asynchronous serial output
• a synchronous clock I/O
• a general purpose I/O
• an asynchronous serial input
• a synchronous serial data I/O
FIGURE 3-17:
FIGURE 3-18:
BLOCK DIAGRAM OF RC6
BLOCK DIAGRAM OF RC7
SPEN
SPEN
TXEN
SYNC
Data Bus
SYNC
EUSART
CK 1
0
Data Bus
D
EUSART
TX 0
1
D
WR
PORTC
WR
PORTC
VDD
Q
1
0
I/O Pin
D
1
0
WR
TRISC
I/O Pin
WR
TRISC
CK Q
VDD
0
1
0
1
CK Q
D
EUSART
DT
Q
Q
CK Q
VSS
Q
CK Q
RD
TRISC
VSS
RD
PORTC
RD
TRISC
EUSART RX/DT
RD
PORTC
TABLE 3-3:
Name
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
0000 0000
0000 0000
DC2B1
DC2B0
CCP2M3
CCP2M2
CCP2M1
CCP2M0
--00 0000
--00 0000
RC6
RC5
RC4
RC3
RC2
RC1
RC0
xxxx xxxx
uuuu uuuu
—
—
STRSYNC
STRD
STRC
STRB
STRA
---0 0001
---0 0001
Bit 7
Bit 6
Bit 5
CCP1CON
P1M1
P1M0
CCP2CON
—
—
RC7
—
PORTC
PSTRCON
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SSPCON
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
0000 0000
T1CON
T1GINV
TMR1GE
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
0000 0000
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
Legend:
x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by PORTC.
DS41291F-page 56
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.6
PORTD and TRISD Registers
The TRISD register (Register 3-12) controls the PORTD
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISD register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
PORTD(1) is a 8-bit wide, bidirectional port. The
corresponding data direction register is TRISD
(Register 3-12). Setting a TRISD bit (= 1) will make the
corresponding PORTD pin an input (i.e., put the
corresponding output driver in a High-Impedance mode).
Clearing a TRISD bit (= 0) will make the corresponding
PORTD pin an output (i.e., enable the output driver and
put the contents of the output latch on the selected pin).
Example 3-5 shows how to initialize PORTD.
EXAMPLE 3-5:
BANKSEL
CLRF
BANKSEL
MOVLW
MOVWF
Reading the PORTD register (Register 3-11) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then written
to the PORT data latch.
INITIALIZING PORTD
PORTD
PORTD
TRISD
B‘00001100’
TRISD
;
;Init PORTD
;
;Set RD<3:2> as inputs
;and set RD<7:4,1:0>
;as outputs
Note 1: PORTD is available on PIC16F884/887
only.
REGISTER 3-11:
PORTD: PORTD REGISTER
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
RD7
RD6
RD5
RD4
RD3
RD2
RD1
RD0
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
RD<7:0>: PORTD General Purpose I/O Pin bit
1 = Port pin is > VIH
0 = Port pin is < VIL
REGISTER 3-12:
TRISD: PORTD TRI-STATE 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
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
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
TRISD<7:0>: PORTD Tri-State Control bit
1 = PORTD pin configured as an input (tri-stated)
0 = PORTD pin configured as an output
© 2009 Microchip Technology Inc.
DS41291F-page 57
PIC16F882/883/884/886/887
3.6.1
RD<4:0>
3.6.3
Figure 3-19 shows the diagram for these pins. These
pins are configured to function as general purpose
I/O’s.
Note:
Figure 3-20 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a PWM output
RD<4:0> is available on PIC16F884/887
only.
FIGURE 3-19:
RD6/P1C(1)
Note 1: RD6/P1C is available on PIC16F884/887
only. See RB1/AN10/P1C/C12IN3- for
this function on PIC16F882/883/886.
BLOCK DIAGRAM OF
RD<4:0>
3.6.4
RD7/P1D(1)
Data Bus
D
WR
PORTD
VDD
Q
CK
Figure 3-20 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• a PWM output
Q
Note 1: RD7/P1D is available on PIC16F884/887
only. See RB4/AN11/P1D for this function
on PIC16F882/883/886.
I/O Pin
D
WR
TRISD
Q
CK
Q
VSS
FIGURE 3-20:
BLOCK DIAGRAM OF
RD<7:5>
RD
TRISD
Data Bus
RD
PORTD
3.6.2
D
WR
PORTD
RD5/P1B(1)
D
WR
TRISD
• a general purpose I/O
• a PWM output
PORTD
PSTRCON
TRISD
Legend:
Q
CCP1
0
1
CK
I/O Pin
Q
Q
VSS
RD
TRISD
Note 1: RD5/P1B is available on PIC16F884/887
only. See RB2/AN8/P1B for this function
on PIC16F882/883/886.
TABLE 3-4:
CK
VDD
Q
1
0
Figure 3-20 shows the diagram for this pin. This pin is
configurable to function as one of the following:
Name
PSTRCON
RD
PORTD
SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
Bit 4
Bit 3
Bit 2
Bit 0
Value on
POR, BOR
Value on
all other
Resets
RD1
RD0
xxxx xxxx
uuuu uuuu
STRB
STRA
---0 0001
---0 0001
TRISD0
1111 1111
1111 1111
Bit 7
Bit 6
Bit 5
Bit 1
RD7
RD6
RD5
RD4
RD3
RD2
—
—
—
STRSYNC
STRD
STRC
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by PORTD.
DS41291F-page 58
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
3.7
PORTE and TRISE Registers
The TRISE register (Register 3-14) controls the PORTE
pin output drivers, even when they are being used as
analog inputs. The user should ensure the bits in the
TRISE register are maintained set when using them as
analog inputs. I/O pins configured as analog input always
read ‘0’.
PORTE(1) is a 4-bit wide, bidirectional port. The
corresponding data direction register is TRISE. Setting a
TRISE bit (= 1) will make the corresponding PORTE pin
an input (i.e., put the corresponding output driver in a
High-Impedance mode). Clearing a TRISE bit (= 0) will
make the corresponding PORTE pin an output (i.e.,
enable the output driver and put the contents of the
output latch on the selected pin). The exception is RE3,
which is input only and its TRIS bit will always read as
‘1’. Example 3-6 shows how to initialize PORTE.
Note:
EXAMPLE 3-6:
Reading the PORTE register (Register 3-13) reads the
status of the pins, whereas writing to it will write to the
PORT latch. All write operations are read-modify-write
operations. Therefore, a write to a port implies that the
port pins are read, this value is modified and then
written to the PORT data latch. RE3 reads ‘0’ when
MCLRE = 1.
Note 1: RE<2:0> pins are
PIC16F884/887 only.
REGISTER 3-13:
U-0
BANKSEL
CLRF
BANKSEL
CLRF
BCF
BANKSEL
MOVLW
MOVWF
on
INITIALIZING PORTE
PORTE
PORTE
ANSEL
ANSEL
STATUS,RP1
TRISE
B‘00001100’
TRISE
;
;Init PORTE
;
;digital I/O
;Bank 1
;
;Set RE<3:2> as inputs
;and set RE<1:0>
;as outputs
PORTE: PORTE REGISTER
U-0
—
available
The ANSEL register must be initialized to
configure an analog channel as a digital
input. Pins configured as analog inputs will
read ‘0’.
—
U-0
—
U-0
R-x
R/W-x
R/W-x
R/W-x
—
RE3
RE2
RE1
RE0
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
Unimplemented: Read as ‘0’
bit 3-0
RD<3:0>: PORTE General Purpose I/O Pin bit
1 = Port pin is > VIH
0 = Port pin is < VIL
REGISTER 3-14:
x = Bit is unknown
TRISE: PORTE TRI-STATE REGISTER
U-0
U-0
U-0
U-0
R-1(1)
R/W-1
R/W-1
R/W-1
—
—
—
—
TRISE3
TRISE2
TRISE1
TRISE0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-4
Unimplemented: Read as ‘0’
bit 3-0
TRISE<3:0>: PORTE Tri-State Control bit
1 = PORTE pin configured as an input (tri-stated)
0 = PORTE pin configured as an output
Note 1:
x = Bit is unknown
TRISE<3> always reads ‘1’.
© 2009 Microchip Technology Inc.
DS41291F-page 59
PIC16F882/883/884/886/887
RE0/AN5(1)
3.7.1
3.7.4
RE3/MCLR/VPP
This pin is configurable to function as one of the
following:
Figure 3-22 shows the diagram for this pin. This pin is
configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
• a general purpose input
• as Master Clear Reset with weak pull-up
Note 1: RE0/AN5 is available on PIC16F884/887
only.
FIGURE 3-22:
BLOCK DIAGRAM OF RE3
VDD
RE1/AN6(1)
3.7.2
MCLRE
This pin is configurable to function as one of the
following:
Data Bus
• a general purpose I/O
• an analog input for the ADC
MCLRE
Reset
RD
TRISE
Note 1: RE1/AN6 is available on PIC16F884/887
only.
Weak
Input
Pin
VSS
MCLRE
RD
PORTE
VSS
RE2/AN7(1)
3.7.3
This pin is configurable to function as one of the
following:
• a general purpose I/O
• an analog input for the ADC
Note 1: RE2/AN7 is available on PIC16F884/887
only.
FIGURE 3-21:
BLOCK DIAGRAM OF
RE<2:0>
Data Bus
D
WR
PORTE
VDD
Q
CK
Q
I/O Pin
D
WR
TRISE
Q
CK
Q
VSS
Analog(1)
Input Mode
RD
TRISE
RD
PORTE
To A/D Converter
Note
1:
ANSEL determines Analog Input mode.
TABLE 3-5:
SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other Resets
ANSEL
ANS7
ANS6
ANS5
ANS4
ANS3
ANS2
ANS1
ANS0
1111 1111
1111 1111
PORTE
—
—
—
—
RE3
RE2
RE1
RE0
---- xxxx
---- uuuu
TRISE
—
—
—
—
TRISE3
TRISE2
TRISE1
TRISE0
---- 1111
---- 1111
Name
Legend:
x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by PORTE
DS41291F-page 60
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.0
OSCILLATOR MODULE (WITH
FAIL-SAFE CLOCK MONITOR)
The oscillator module can be configured in one of eight
clock modes.
4.1
Overview
1.
2.
3.
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 4-1
illustrates a block diagram of the oscillator module.
4.
5.
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 two
internal oscillators, with a choice of speeds selectable via
software. Additional clock features include:
6.
7.
8.
• Selectable system clock source between external
or internal 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.
FIGURE 4-1:
EC – External clock with I/O on OSC2/CLKOUT.
LP – 32 kHz Low-Power Crystal mode.
XT – Medium Gain Crystal or Ceramic Resonator
Oscillator mode.
HS – High Gain Crystal or Ceramic Resonator
mode.
RC – External Resistor-Capacitor (RC) with
FOSC/4 output on OSC2/CLKOUT.
RCIO – External Resistor-Capacitor (RC) with I/
O on OSC2/CLKOUT.
INTOSC – Internal oscillator with FOSC/4 output
on OSC2 and I/O on OSC1/CLKIN.
INTOSCIO – Internal oscillator with I/O on
OSC1/CLKIN and OSC2/CLKOUT.
Clock Source modes are configured by the FOSC<2:0>
bits in the Configuration Word Register 1 (CONFIG1).
The internal clock can be generated from two internal
oscillators. The HFINTOSC is a calibrated highfrequency oscillator. The LFINTOSC is an uncalibrated
low-frequency oscillator.
SIMPLIFIED PIC® MCU CLOCK SOURCE BLOCK DIAGRAM
FOSC<2:0>
(Configuration Word Register 1)
SCS<0>
(OSCCON Register)
External Oscillator
OSC2
Sleep
MUX
LP, XT, HS, RC, RCIO, EC
OSC1
IRCF<2:0>
(OSCCON Register)
8 MHz
Internal Oscillator
4 MHz
System Clock
(CPU and Peripherals)
INTOSC
111
110
101
1 MHz
100
500 kHz
250 kHz
125 kHz
LFINTOSC
31 kHz
31 kHz
011
MUX
HFINTOSC
8 MHz
Postscaler
2 MHz
010
001
000
Power-up Timer (PWRT)
Watchdog Timer (WDT)
Fail-Safe Clock Monitor (FSCM)
© 2009 Microchip Technology Inc.
DS41291F-page 61
PIC16F882/883/884/886/887
4.2
Oscillator Control
The Oscillator Control (OSCCON) register (Figure 4-1)
controls the system clock and frequency selection
options. The OSCCON register contains the following
bits:
• Frequency selection bits (IRCF)
• Frequency Status bits (HTS, LTS)
• System clock control bits (OSTS, SCS)
REGISTER 4-1:
OSCCON: OSCILLATOR CONTROL REGISTER
U-0
R/W-1
R/W-1
R/W-0
R-1
R-0
R-0
R/W-0
—
IRCF2
IRCF1
IRCF0
OSTS(1)
HTS
LTS
SCS
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 6-4
IRCF<2:0>: Internal Oscillator Frequency Select bits
111 = 8 MHz
110 = 4 MHz (default)
101 = 2 MHz
100 = 1 MHz
011 = 500 kHz
010 = 250 kHz
001 = 125 kHz
000 = 31 kHz (LFINTOSC)
bit 3
OSTS: Oscillator Start-up Time-out Status bit(1)
1 = Device is running from the clock defined by FOSC<2:0> of the CONFIG1 register
0 = Device is running from the internal oscillator (HFINTOSC or LFINTOSC)
bit 2
HTS: HFINTOSC Status bit (High Frequency – 8 MHz to 125 kHz)
1 = HFINTOSC is stable
0 = HFINTOSC is not stable
bit 1
LTS: LFINTOSC Stable bit (Low Frequency – 31 kHz)
1 = LFINTOSC is stable
0 = LFINTOSC is not stable
bit 0
SCS: System Clock Select bit
1 = Internal oscillator is used for system clock
0 = Clock source defined by FOSC<2:0> of the CONFIG1 register
Note 1:
Bit resets to ‘0’ with Two-Speed Start-up and LP, XT or HS selected as the Oscillator mode or Fail-Safe
mode is enabled.
DS41291F-page 62
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.3
Clock Source Modes
Clock Source modes can be classified as external or
internal.
• External Clock modes rely on external circuitry for
the clock source. Examples are: oscillator modules (EC mode), quartz crystal resonators or
ceramic resonators (LP, XT and HS modes) and
Resistor-Capacitor (RC) mode circuits.
• Internal clock sources are contained internally
within the oscillator module. The oscillator module
has two internal oscillators: the 8 MHz HighFrequency Internal Oscillator (HFINTOSC) and
the 31 kHz Low-Frequency Internal Oscillator
(LFINTOSC).
The system clock can be selected between external or
internal clock sources via the System Clock Select
(SCS) bit of the OSCCON register. See Section 4.6
“Clock Switching” for additional information.
TABLE 4-1:
4.4
External Clock Modes
4.4.1
OSCILLATOR START-UP TIMER (OST)
If 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 4-1.
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 4.7 “TwoSpeed Clock Start-up Mode”).
OSCILLATOR DELAY EXAMPLES
Switch From
Switch To
Frequency
Oscillator Delay
Sleep/POR
LFINTOSC
HFINTOSC
31 kHz
125 kHz to 8 MHz
Oscillator Warm-up Delay (TWARM)
Sleep/POR
EC, RC
DC – 20 MHz
2 cycles
LFINTOSC (31 kHz)
EC, RC
DC – 20 MHz
1 cycle of each
Sleep/POR
LP, XT, HS
32 kHz to 20 MHz
1024 Clock Cycles (OST)
LFINTOSC (31 kHz)
HFINTOSC
125 kHz to 8 MHz
1 μs (approx.)
4.4.2
EC MODE
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 4-2 shows the pin
connections for EC mode.
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.
© 2009 Microchip Technology Inc.
FIGURE 4-2:
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 the
Section 1.0 “Device Overview”.
DS41291F-page 63
PIC16F882/883/884/886/887
4.4.3
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 4-3). The mode selects a low,
medium or high gain setting of the internal inverteramplifier to support various resonator types and speed.
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 designed to
drive only 32.768 kHz tuning-fork type crystals (watch
crystals).
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.
3: For oscillator design assistance, reference
the following Microchip Applications 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 selects the highest gain setting of the
internal inverter-amplifier. HS mode current consumption
is the highest of the three modes. This mode is best
suited for resonators that require a high drive setting.
Figure 4-3 and Figure 4-4 show typical circuits for
quartz crystal and ceramic resonators, respectively.
FIGURE 4-3:
FIGURE 4-4:
CERAMIC RESONATOR
OPERATION
(XT OR HS MODE)
QUARTZ CRYSTAL
OPERATION (LP, XT OR
HS MODE)
PIC® MCU
OSC1/CLKIN
PIC® MCU
C1
To Internal
Logic
OSC1/CLKIN
C1
Quartz
Crystal
C2
RP(3)
To Internal
Logic
RS(1)
RF(2)
RF(2)
Sleep
Sleep
C2 Ceramic
RS(1)
Resonator
OSC2/CLKOUT
Note 1:
OSC2/CLKOUT
A series resistor (RS) may be required for
ceramic resonators with low drive level.
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 MΩ to 10 MΩ).
2:
The value of RF varies with the Oscillator mode
selected (typically between 2 MΩ to 10 MΩ).
3: An additional parallel feedback resistor (RP)
may be required for proper ceramic resonator
operation.
DS41291F-page 64
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.4.4
EXTERNAL RC MODES
4.5
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.
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 4-5 shows the
external RC mode connections.
FIGURE 4-5:
VDD
EXTERNAL RC MODES
PIC® MCU
REXT
OSC1/CLKIN
Internal
Clock
CEXT
Internal Clock Modes
The oscillator module has two independent, internal
oscillators that can be configured or selected as the
system clock source.
1.
2.
The HFINTOSC (High-Frequency Internal
Oscillator) is factory calibrated and operates at
8 MHz. The frequency of the HFINTOSC can be
user-adjusted via software using the OSCTUNE
register (Register 4-2).
The LFINTOSC (Low-Frequency Internal
Oscillator) is uncalibrated and operates at
31 kHz.
The system clock speed can be selected via software
using the Internal Oscillator Frequency Select bits
IRCF<2:0> of the OSCCON register.
The system clock can be selected between external or
internal clock sources via the System Clock Selection
(SCS) bit of the OSCCON register. See Section 4.6
“Clock Switching” for more information.
4.5.1
VSS
FOSC/4 or
I/O(2)
OSC2/CLKOUT
(1)
Recommended values: 10 kΩ ≤ REXT ≤ 100 kΩ, <3V
3 kΩ ≤ REXT ≤ 100 kΩ, 3-5V
CEXT > 20 pF, 2-5V
Note 1:
2:
Alternate pin functions are listed in the
Section 1.0 “Device Overview”.
Output depends upon RC or RCIO Clock
mode.
In RCIO mode, the RC circuit is connected to OSC1.
OSC2 becomes an additional 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:
• 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.
INTOSC AND INTOSCIO MODES
The INTOSC and INTOSCIO modes configure the
internal oscillators as the system clock source when
the device is programmed using the oscillator selection
or the FOSC<2:0> bits in the Configuration Word
Register 1 (CONFIG1).
In INTOSC mode, OSC1/CLKIN is available for general
purpose I/O. OSC2/CLKOUT outputs the selected
internal oscillator frequency divided by 4. The CLKOUT
signal may be used to provide a clock for external
circuitry, synchronization, calibration, test or other
application requirements.
In INTOSCIO mode, OSC1/CLKIN and OSC2/CLKOUT
are available for general purpose I/O.
4.5.2
HFINTOSC
The High-Frequency Internal Oscillator (HFINTOSC) is
a factory calibrated 8 MHz internal clock source. The
frequency of the HFINTOSC can be altered via
software using the OSCTUNE register (Register 4-2).
The output of the HFINTOSC connects to a postscaler
and multiplexer (see Figure 4-1). One of seven
frequencies can be selected via software using the
IRCF<2:0> bits of the OSCCON register. See
Section 4.5.4 “Frequency Select Bits (IRCF)” for
more information.
The HFINTOSC is enabled by selecting any frequency
between 8 MHz and 125 kHz by setting the IRCF<2:0>
bits of the OSCCON register ≠ 000. Then, set the
System Clock Source (SCS) bit of the OSCCON
register to ‘1’ or enable Two-Speed Start-up by setting
the IESO bit in the Configuration Word Register 1
(CONFIG1) to ‘1’.
The HF Internal Oscillator (HTS) bit of the OSCCON
register indicates whether the HFINTOSC is stable or not.
© 2009 Microchip Technology Inc.
DS41291F-page 65
PIC16F882/883/884/886/887
4.5.2.1
OSCTUNE Register
The HFINTOSC is factory calibrated but can be
adjusted in software by writing to the OSCTUNE
register (Register 4-2).
The default value of the OSCTUNE register is ‘0’. The
value is a 5-bit two’s complement number.
REGISTER 4-2:
When the OSCTUNE register is modified, the
HFINTOSC frequency will begin shifting to the new
frequency. Code execution continues during this shift.
There is no indication that the shift has occurred.
OSCTUNE does not affect the LFINTOSC frequency.
Operation of features that depend on the LFINTOSC
clock source frequency, such as the Power-up Timer
(PWRT), Watchdog Timer (WDT), Fail-Safe Clock
Monitor (FSCM) and peripherals, are not affected by the
change in frequency.
OSCTUNE: OSCILLATOR TUNING REGISTER
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
TUN4
TUN3
TUN2
TUN1
TUN0
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 4-0
TUN<4:0>: Frequency Tuning bits
01111 = Maximum frequency
01110 =
•
•
•
00001 =
00000 = Oscillator module is running at the factory-calibrated frequency.
11111 =
•
•
•
10000 = Minimum frequency
DS41291F-page 66
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.5.3
LFINTOSC
The Low-Frequency Internal Oscillator (LFINTOSC) is
an uncalibrated 31 kHz internal clock source.
The output of the LFINTOSC connects to a postscaler
and multiplexer (see Figure 4-1). Select 31 kHz, via
software, using the IRCF<2:0> bits of the OSCCON
register. See Section 4.5.4 “Frequency Select Bits
(IRCF)” for more information. The LFINTOSC is also the
frequency for the Power-up Timer (PWRT), Watchdog
Timer (WDT) and Fail-Safe Clock Monitor (FSCM).
The LFINTOSC is enabled by selecting 31 kHz
(IRCF<2:0> bits of the OSCCON register = 000) as the
system clock source (SCS bit of the OSCCON
register = 1), or when any of the following are enabled:
• Two-Speed Start-up IESO bit of the Configuration
Word Register 1 = 1 and IRCF<2:0> bits of the
OSCCON register = 000
• Power-up Timer (PWRT)
• Watchdog Timer (WDT)
• Fail-Safe Clock Monitor (FSCM)
The LF Internal Oscillator (LTS) bit of the OSCCON
register indicates whether the LFINTOSC is stable or
not.
4.5.4
FREQUENCY SELECT BITS (IRCF)
The output of the 8 MHz HFINTOSC and 31 kHz
LFINTOSC connects to a postscaler and multiplexer
(see Figure 4-1). The Internal Oscillator Frequency
Select bits IRCF<2:0> of the OSCCON register select
the frequency output of the internal oscillators. One of
eight frequencies can be selected via software:
•
•
•
•
•
•
•
•
8 MHz
4 MHz (Default after Reset)
2 MHz
1 MHz
500 kHz
250 kHz
125 kHz
31 kHz (LFINTOSC)
Note:
4.5.5
HFINTOSC AND LFINTOSC CLOCK
SWITCH TIMING
When switching between the LFINTOSC and the
HFINTOSC, the new oscillator may already be shut
down to save power (see Figure 4-6). If this is the case,
there is a delay after the IRCF<2:0> bits of the
OSCCON register are modified before the frequency
selection takes place. The LTS and HTS bits of the
OSCCON register will reflect the current active status
of the LFINTOSC and HFINTOSC oscillators. The
timing of a frequency selection is as follows:
1.
2.
3.
4.
5.
6.
IRCF<2:0> bits of the OSCCON register are
modified.
If the new clock is shut down, a clock start-up
delay is started.
Clock switch circuitry waits for a falling edge of
the current clock.
CLKOUT is held low and the clock switch
circuitry waits for a rising edge in the new clock.
CLKOUT is now connected with the new clock.
LTS and HTS bits of the OSCCON register are
updated as required.
Clock switch is complete.
See Figure 4-1 for more details.
If the internal oscillator speed selected is between
8 MHz and 125 kHz, there is no start-up delay before
the new frequency is selected. This is because the old
and new frequencies are derived from the HFINTOSC
via the postscaler and multiplexer.
Start-up delay specifications are located in the
oscillator tables of Section 17.0 “Electrical
Specifications”.
Following any Reset, the IRCF<2:0> bits of
the OSCCON register are set to ‘110’ and
the frequency selection is set to 4 MHz.
The user can modify the IRCF bits to
select a different frequency.
© 2009 Microchip Technology Inc.
DS41291F-page 67
PIC16F882/883/884/886/887
FIGURE 4-6:
HFINTOSC
INTERNAL OSCILLATOR SWITCH TIMING
LFINTOSC (FSCM and WDT disabled)
HFINTOSC
Start-up Time
2-cycle Sync
Running
LFINTOSC
IRCF <2:0>
≠0
=0
System Clock
HFINTOSC
LFINTOSC (Either FSCM or WDT enabled)
HFINTOSC
2-cycle Sync
Running
LFINTOSC
≠0
IRCF <2:0>
=0
System Clock
LFINTOSC
HFINTOSC
LFINTOSC turns off unless WDT or FSCM is enabled
LFINTOSC
Start-up Time
2-cycle Sync
Running
HFINTOSC
IRCF <2:0>
=0
¼0
System Clock
DS41291F-page 68
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.6
Clock Switching
The system clock source can be switched between
external and internal clock sources via software using
the System Clock Select (SCS) bit of the OSCCON
register.
4.6.1
SYSTEM CLOCK SELECT (SCS) BIT
The System Clock Select (SCS) bit of the OSCCON
register selects the system clock source that is used for
the CPU and peripherals.
• When the SCS bit of the OSCCON register = 0,
the system clock source is determined by
configuration of the FOSC<2:0> bits in the
Configuration Word Register 1 (CONFIG1).
• When the SCS bit of the OSCCON register = 1,
the system clock source is chosen by the internal
oscillator frequency selected by the IRCF<2:0>
bits of the OSCCON register. After a Reset, the
SCS bit of the OSCCON register is always
cleared.
Note:
4.6.2
Any automatic clock switch, which may
occur from Two-Speed Start-up or Fail-Safe
Clock Monitor, does not update the SCS bit
of the OSCCON register. The user can
monitor the OSTS bit 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<2:0> bits in the Configuration
Word Register 1 (CONFIG1), or from the internal clock
source. In particular, OSTS indicates that the Oscillator
Start-up Timer (OST) has timed out for LP, XT or HS
modes.
4.7
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.
When the oscillator module is configured for LP, XT or
HS modes, the Oscillator Start-up Timer (OST) is
enabled (see Section 4.4.1 “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.
4.7.1
TWO-SPEED START-UP MODE
CONFIGURATION
Two-Speed Start-up mode is configured by the
following settings:
• IESO (of the Configuration Word Register 1) = 1;
Internal/External Switchover bit (Two-Speed Startup mode enabled).
• SCS (of the OSCCON register) = 0.
• FOSC<2:0> bits in the Configuration Word
Register 1 (CONFIG1) configured for LP, XT or
HS mode.
Two-Speed Start-up mode is entered after:
• Power-on Reset (POR) and, if enabled, after
Power-up Timer (PWRT) has expired, or
• Wake-up from Sleep.
If the external clock oscillator is configured to be
anything other than LP, XT or HS mode, then Twospeed Start-up is disabled. This is because the external
clock oscillator does not require any stabilization time
after POR or an exit from Sleep.
4.7.2
1.
2.
3.
4.
5.
6.
7.
TWO-SPEED START-UP
SEQUENCE
Wake-up from Power-on Reset or Sleep.
Instructions begin execution by the internal
oscillator at the frequency set in the IRCF<2:0>
bits of the OSCCON register.
OST enabled to count 1024 clock cycles.
OST timed out, wait for falling edge of the
internal oscillator.
OSTS is set.
System clock held low until the next falling edge
of new clock (LP, XT or HS mode).
System clock is switched to external clock
source.
This mode allows the application to wake-up from
Sleep, perform a few instructions using the INTOSC
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.
© 2009 Microchip Technology Inc.
DS41291F-page 69
PIC16F882/883/884/886/887
4.7.3
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 the Configuration Word Register 1
(CONFIG1), or the internal oscillator.
FIGURE 4-7:
TWO-SPEED START-UP
HFINTOSC
TOST
OSC1
0
1
1022 1023
OSC2
Program Counter
PC - N
PC
PC + 1
System Clock
DS41291F-page 70
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
4.8
4.8.3
Fail-Safe Clock Monitor
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
Configuration Word Register 1 (CONFIG1). The FSCM
is applicable to all external Oscillator modes (LP, XT,
HS, EC, RC and RCIO).
FIGURE 4-8:
FSCM BLOCK DIAGRAM
Clock Monitor
Latch
External
Clock
LFINTOSC
Oscillator
÷ 64
31 kHz
(~32 μs)
488 Hz
(~2 ms)
S
Q
R
Q
The Fail-Safe condition is cleared after a Reset,
executing a SLEEP instruction or toggling the SCS bit
of the OSCCON register. When the SCS bit is toggled,
the OST is restarted. 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 will be operating
from the external clock source. The Fail-Safe condition
must be cleared before the OSFIF flag can be cleared.
4.8.4
4.8.1
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 4-8. 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.
4.8.2
RESET OR WAKE-UP FROM SLEEP
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. When
the FSCM is enabled, the Two-Speed Start-up is also
enabled. Therefore, the device will always be executing
code while the OST is operating.
Note:
Sample Clock
FAIL-SAFE CONDITION CLEARING
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.
FAIL-SAFE OPERATION
When the external clock fails, the FSCM switches the
device clock to an internal clock source and sets the bit
flag OSFIF of the PIR2 register. Setting this flag will
generate an interrupt if the OSFIE 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.
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.
© 2009 Microchip Technology Inc.
DS41291F-page 71
PIC16F882/883/884/886/887
FIGURE 4-9:
FSCM TIMING DIAGRAM
Sample Clock
Oscillator
Failure
System
Clock
Output
Clock Monitor Output
(Q)
Failure
Detected
OSCFIF
Test
Note:
SUMMARY OF REGISTERS ASSOCIATED WITH CLOCK SOURCES
Name
Bit 7
CONFIG1(2)
OSCTUNE
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.
TABLE 4-2:
OSCCON
Test
Value on
POR, BOR
Value on
all other
Resets(1)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CPD
CP
MCLRE
PWRTE
WDTE
FOSC2
FOSC1
FOSC0
—
—
—
IRCF2
IRCF1
IRCF0
OSTS
HTS
LTS
SCS
-110 x000
-110 x000
—
—
—
TUN4
TUN3
TUN2
TUN1
TUN0
---0 0000
---u uuuu
PIE2
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
0000 00-0
PIR2
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
0000 00-0
0000 00-0
Legend:
Note 1:
2:
x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by oscillators.
Other (non Power-up) Resets include MCLR Reset and Watchdog Timer Reset during normal operation.
See Configuration Word Register 1 (Register 14-1) for operation of all register bits.
DS41291F-page 72
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
5.0
TIMER0 MODULE
5.1
Timer0 Operation
The Timer0 module is an 8-bit timer/counter with the
following features:
When used as a timer, the Timer0 module can be used
as either an 8-bit timer or an 8-bit counter.
•
•
•
•
•
5.1.1
8-bit timer/counter register (TMR0)
8-bit prescaler (shared with Watchdog Timer)
Programmable internal or external clock source
Programmable external clock edge selection
Interrupt on overflow
8-BIT TIMER MODE
When used as a timer, the Timer0 module will
increment every instruction cycle (without prescaler).
Timer mode is selected by clearing the T0CS bit of the
OPTION register to ‘0’.
Figure 5-1 is a block diagram of the Timer0 module.
When TMR0 is written, the increment is inhibited for
two instruction cycles immediately following the write.
Note:
5.1.2
The value written to the TMR0 register can
be adjusted, in order to account for the two
instruction cycle delay when TMR0 is
written.
8-BIT COUNTER MODE
When used as a counter, the Timer0 module will
increment on every rising or falling edge of the T0CKI
pin. The incrementing edge is determined by the T0SE
bit of the OPTION register. Counter mode is selected by
setting the T0CS bit of the OPTION register to ‘1’.
FIGURE 5-1:
TIMER0/WDT PRESCALER BLOCK DIAGRAM
FOSC/4
Data Bus
0
8
1
Sync
2 Tcy
1
T0CKI
pin
TMR0
0
0
T0SE
T0CS
Set Flag bit T0IF
on Overflow
8-bit
Prescaler
PSA
1
8
PSA
WDTE
SWDTEN
PS<2:0>
16-bit
Prescaler
31 kHz
INTOSC
1
WDT
Time-out
0
16
Watchdog
Timer
PSA
WDTPS<3:0>
Note
1:
T0SE, T0CS, PSA, PS<2:0> are bits in the OPTION register.
2:
SWDTEN and WDTPS<3:0> are bits in the WDTCON register.
3:
WDTE bit is in the Configuration Word Register1.
© 2009 Microchip Technology Inc.
DS41291F-page 73
PIC16F882/883/884/886/887
5.1.3
SOFTWARE PROGRAMMABLE
PRESCALER
A single software programmable prescaler is available
for use with either Timer0 or the Watchdog Timer
(WDT), but not both simultaneously. The prescaler
assignment is controlled by the PSA bit of the OPTION
register. To assign the prescaler to Timer0, the PSA bit
must be cleared to a ‘0’.
There are 8 prescaler options for the Timer0 module
ranging from 1:2 to 1:256. The prescale values are
selectable via the PS<2:0> bits of the OPTION register.
In order to have a 1:1 prescaler value for the Timer0
module, the prescaler must be assigned to the WDT
module.
The prescaler is not readable or writable. When
assigned to the Timer0 module, all instructions writing to
the TMR0 register will clear the prescaler.
When the prescaler is assigned to WDT, a CLRWDT
instruction will clear the prescaler along with the WDT.
5.1.3.1
Switching Prescaler Between
Timer0 and WDT Modules
As a result of having the prescaler assigned to either
Timer0 or the WDT, it is possible to generate an
unintended device Reset when switching prescaler
values. When changing the prescaler assignment from
Timer0 to the WDT module, the instruction sequence
shown in Example 5-1, must be executed.
EXAMPLE 5-1:
CHANGING PRESCALER
(TIMER0 → WDT)
BANKSEL
CLRWDT
CLRF
TMR0
BANKSEL
BSF
CLRWDT
OPTION_REG
OPTION_REG,PSA
MOVLW
ANDWF
IORLW
MOVWF
b’11111000’
OPTION_REG,W
b’00000101’
OPTION_REG
TMR0
DS41291F-page 74
;
;Clear WDT
;Clear TMR0 and
;prescaler
;
;Select WDT
;
;
;Mask prescaler
;bits
;Set WDT prescaler
;to 1:32
When changing the prescaler assignment from the
WDT to the Timer0 module, the following instruction
sequence must be executed (see Example 5-2).
EXAMPLE 5-2:
CHANGING PRESCALER
(WDT → TIMER0)
CLRWDT
;Clear WDT and
;prescaler
BANKSEL OPTION_REG
;
MOVLW
b’11110000’ ;Mask TMR0 select and
ANDWF
OPTION_REG,W ;prescaler bits
IORLW
b’00000011’ ;Set prescale to 1:16
MOVWF
OPTION_REG
;
5.1.4
TIMER0 INTERRUPT
Timer0 will generate an interrupt when the TMR0
register overflows from FFh to 00h. The T0IF interrupt
flag bit of the INTCON register is set every time the
TMR0 register overflows, regardless of whether or not
the Timer0 interrupt is enabled. The T0IF bit must be
cleared in software. The Timer0 interrupt enable is the
T0IE bit of the INTCON register.
Note:
5.1.5
The Timer0 interrupt cannot wake the
processor from Sleep since the timer is
frozen during Sleep.
USING TIMER0 WITH AN
EXTERNAL CLOCK
When Timer0 is in Counter mode, the synchronization
of the T0CKI input and the Timer0 register is accomplished by sampling the prescaler output on the Q2 and
Q4 cycles of the internal phase clocks. Therefore, the
high and low periods of the external clock source must
meet the timing requirements as shown in the
Section 17.0 “Electrical Specifications”.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 5-1:
OPTION_REG: OPTION 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
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
RBPU: PORTB Pull-up Enable bit
1 = PORTB pull-ups are disabled
0 = PORTB pull-ups are enabled by individual PORT latch values
bit 6
INTEDG: Interrupt Edge Select bit
1 = Interrupt on rising edge of INT pin
0 = Interrupt on falling edge of INT pin
bit 5
T0CS: TMR0 Clock Source Select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (FOSC/4)
bit 4
T0SE: TMR0 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: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
bit 2-0
PS<2:0>: Prescaler Rate Select bits
BIT VALUE
000
001
010
011
100
101
110
111
Note 1:
WDT RATE
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
1:1
1:2
1:4
1:8
1 : 16
1 : 32
1 : 64
1 : 128
A dedicated 16-bit WDT postscaler is available. See Section 14.5 “Watchdog Timer (WDT)” for more
information.
TABLE 5-1:
Name
TMR0
INTCON
OPTION_REG
TRISA
TMR0 RATE
x = Bit is unknown
SUMMARY OF REGISTERS ASSOCIATED WITH TIMER0
Bit 7
Bit 6
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x 0000 000x
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111 1111 1111
Timer0 Module Register
GIE
PEIE
RBPU INTEDG
Value on
all other
Resets
Bit 4
Bit 5
xxxx xxxx uuuu uuuu
TRISA7 TRISA6 TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 1111 1111 1111 1111
Legend: – = Unimplemented locations, read as ‘0’, u = unchanged, x = unknown. Shaded cells are not used by the
Timer0 module.
© 2009 Microchip Technology Inc.
DS41291F-page 75
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6.0
TIMER1 MODULE WITH GATE
CONTROL
The Timer1 module is a 16-bit timer/counter with the
following features:
•
•
•
•
•
•
•
•
•
•
•
16-bit timer/counter register pair (TMR1H:TMR1L)
Programmable internal or external clock source
3-bit prescaler
Optional LP oscillator
Synchronous or asynchronous operation
Timer1 gate (count enable) via comparator or
T1G pin
Interrupt on overflow
Wake-up on overflow (external clock,
Asynchronous mode only)
Time base for the Capture/Compare function
Special Event Trigger (with ECCP)
Comparator output synchronization to Timer1
clock
6.1
Timer1 Operation
The Timer1 module is a 16-bit incrementing counter
which is accessed through the TMR1H:TMR1L register
pair. Writes to TMR1H or TMR1L directly update the
counter.
When used with an internal clock source, the module is
a timer. When used with an external clock source, the
module can be used as either a timer or counter.
6.2
Clock Source Selection
The TMR1CS bit of the T1CON register is used to select
the clock source. When TMR1CS = 0, the clock source
is FOSC/4. When TMR1CS = 1, the clock source is
supplied externally.
Clock Source
TMR1CS
FOSC/4
0
T1CKI pin
1
Figure 6-1 is a block diagram of the Timer1 module.
FIGURE 6-1:
TIMER1 BLOCK DIAGRAM
TMR1GE
T1GINV
TMR1ON
Set flag bit
TMR1IF on
Overflow
To C2 Comparator Module
Timer1 Clock
TMR1(2)
TMR1H
TMR1L
Synchronized
clock input
0
EN
1
Oscillator
(1)
T1OSO/T1CKI
T1SYNC
1
Synchronize(3)
Prescaler
1, 2, 4, 8
det
0
T1OSI
2
T1CKPS<1:0>
TMR1CS
1
T1G
INTOSC
Without CLKOUT
T1OSCEN
Note 1:
2:
3:
4:
DS41291F-page 76
SYNCC2OUT(4)
FOSC/4
Internal
Clock
0
T1GSS
ST Buffer is low power type when using LP osc, or high speed type when using T1CKI.
Timer1 register increments on rising edge.
Synchronize does not operate while in Sleep.
SYNCC2OUT is synchronized when the C2SYNC bit of the CM2CON1 register is set.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
6.2.1
INTERNAL CLOCK SOURCE
When the internal clock source is selected the
TMR1H:TMR1L register pair will increment on multiples
of FOSC as determined by the Timer1 prescaler.
6.2.2
EXTERNAL CLOCK SOURCE
When the external clock source is selected, the Timer1
module may work as a timer or a counter.
When counting, Timer1 is incremented on the rising
edge of the external clock input T1CKI. In addition, the
Counter mode clock can be synchronized to the
microcontroller system clock or run asynchronously.
6.5
If control bit T1SYNC of the T1CON register is set, the
external clock input is not synchronized. The timer
continues to increment asynchronous to the internal
phase clocks. 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 6.5.1 “Reading and Writing
Timer1 in Asynchronous Counter Mode”).
Note:
If an external clock oscillator is needed (and the
microcontroller is using the INTOSC without CLKOUT),
Timer1 can use the LP oscillator as a clock source.
In Counter mode, a falling edge must be registered by
the counter prior to the first incrementing rising edge
after one or more of the following conditions (see
Figure 6-2):
• Timer1 is enabled after POR or BOR Reset
• A write to TMR1H or TMR1L
• T1CKI is high when Timer1 is disabled and when
Timer1 is reenabled T1CKI is low.
6.3
Timer1 Prescaler
Timer1 has four prescaler options allowing 1, 2, 4 or 8
divisions of the clock input. The T1CKPS bits of the
T1CON register control the prescale counter. The
prescale counter is not directly readable or writable;
however, the prescaler counter is cleared upon a write to
TMR1H or TMR1L.
6.4
6.5.1
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 a single spurious
increment.
READING AND WRITING TIMER1 IN
ASYNCHRONOUS COUNTER
MODE
Reading TMR1H or TMR1L 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 TMR1H:TTMR1L register
pair.
Timer1 Oscillator
A low-power 32.768 kHz oscillator is built-in between
pins T1OSI (input) and T1OSO (amplifier output). The
oscillator is enabled by setting the T1OSCEN control
bit of the T1CON register. The oscillator will continue to
run during Sleep.
The Timer1 oscillator is identical to the LP oscillator.
The user must provide a software time delay to ensure
proper oscillator start-up.
TRISC0 and TRISC1 bits are set when the Timer1
oscillator is enabled. RC0 and RC1 bits read as ‘0’ and
TRISC0 and TRISC1 bits read as ‘1’.
Note:
Timer1 Operation in
Asynchronous Counter Mode
The oscillator requires a start-up and
stabilization time before use. Thus,
T1OSCEN should be set and a suitable
delay observed prior to enabling Timer1.
© 2009 Microchip Technology Inc.
6.6
Timer1 Gate
Timer1 gate source is software configurable to be the
T1G pin or the output of Comparator C2. This allows the
device to directly time external events using T1G or
analog events using Comparator C2. See the
CM2CON1 register (Register 8-3) for selecting the
Timer1 gate source. This feature can simplify the
software for a Delta-Sigma A/D converter and many
other applications. For more information on Delta-Sigma
A/D converters, see the Microchip web site
(www.microchip.com).
Note:
TMR1GE bit of the T1CON register must be
set to use the Timer1 gate.
Timer1 gate can be inverted using the T1GINV bit of
the T1CON register, whether it originates from the T1G
pin or Comparator C2 output. This configures Timer1 to
measure either the active-high or active-low time
between events.
DS41291F-page 77
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6.7
Timer1 Interrupt
The Timer1 register pair (TMR1H:TMR1L) increments
to FFFFh and rolls over to 0000h. When Timer1 rolls
over, the Timer1 interrupt flag bit of the PIR1 register is
set. To enable the interrupt on rollover, you must set
these bits:
• Timer1 interrupt enable bit of the PIE1 register
• PEIE bit of the INTCON register
• GIE bit of the INTCON register
The interrupt is cleared by clearing the TMR1IF bit in
the Interrupt Service Routine.
Note:
6.8
The TMR1H:TTMR1L register pair and the
TMR1IF bit should be cleared before
enabling interrupts.
Timer1 Operation During Sleep
Timer1 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:
• TMR1ON bit of the T1CON register must be set
• TMR1IE bit of the PIE1 register must be set
• PEIE bit of the INTCON register must be set
The device will wake-up on an overflow and execute
the next instruction. If the GIE bit of the INTCON
register is set, the device will call the Interrupt Service
Routine (0004h).
6.9
ECCP Capture/Compare Time Base
The ECCP module uses the TMR1H:TMR1L register
pair as the time base when operating in Capture or
Compare mode.
In Capture mode, the value in the TMR1H:TMR1L
register pair is copied into the CCPRxH:CCPRxL
register pair on a configured event.
FIGURE 6-2:
In Compare mode, an event is triggered when the value
CCPRxH:CCPRxL register pair matches the value in
the TMR1H:TMR1L register pair. This event can be a
Special Event Trigger.
See Section 11.0 “Capture/Compare/PWM Modules
(CCP1 and CCP2)” for more information.
6.10
ECCP Special Event Trigger
If an ECCP is configured to trigger a special event, the
trigger will clear the TMR1H:TMR1L register pair. This
special event does not cause a Timer1 interrupt. The
ECCP module may still be configured to generate a
ECCP interrupt.
In this mode of operation, the CCPRxH:CCPRxL
register pair effectively becomes the period register for
Timer1.
Timer1 should be synchronized to the FOSC to utilize
the Special Event Trigger. Asynchronous operation of
Timer1 can cause a Special Event Trigger to be
missed.
In the event that a write to TMR1H or TMR1L coincides
with a Special Event Trigger from the ECCP, the write
will take precedence.
For more information, see Section 11.0 “Capture/
Compare/PWM Modules (CCP1 and CCP2)”.
6.11
Comparator Synchronization
The same clock used to increment Timer1 can also be
used to synchronize the comparator output. This
feature is enabled in the Comparator module.
When using the comparator for Timer1 gate, the
comparator output should be synchronized to Timer1.
This ensures Timer1 does not miss an increment if the
comparator changes.
For more information, see Section 8.0 “Comparator
Module”.
TIMER1 INCREMENTING EDGE
T1CKI = 1
when TMR1
Enabled
T1CKI = 0
when TMR1
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.
DS41291F-page 78
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
6.12
Timer1 Control Register
The Timer1 Control register (T1CON), shown in
Register 6-1, is used to control Timer1 and select the
various features of the Timer1 module.
REGISTER 6-1:
R/W-0
R/W-0
(1)
T1GINV
T1CON: TIMER1 CONTROL REGISTER
(2)
TMR1GE
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
T1GINV: Timer1 Gate Invert bit(1)
1 = Timer1 gate is active-high (Timer1 counts when gate is high)
0 = Timer1 gate is active-low (Timer1 counts when gate is low)
bit 6
TMR1GE: Timer1 Gate Enable bit(2)
If TMR1ON = 0:
This bit is ignored
If TMR1ON = 1:
1 = Timer1 counting is controlled by the Timer1 Gate function
0 = Timer1 is always counting
bit 5-4
T1CKPS<1:0>: Timer1 Input Clock Prescale Select bits
11 = 1:8 Prescale Value
10 = 1:4 Prescale Value
01 = 1:2 Prescale Value
00 = 1:1 Prescale Value
bit 3
T1OSCEN: LP Oscillator Enable Control bit
1 = LP oscillator is enabled for Timer1 clock
0 = LP oscillator is off
bit 2
T1SYNC: Timer1 External Clock Input Synchronization Control bit
TMR1CS = 1:
1 = Do not synchronize external clock input
0 = Synchronize external clock input
TMR1CS = 0:
This bit is ignored. Timer1 uses the internal clock
bit 1
TMR1CS: Timer1 Clock Source Select bit
1 = External clock from T1CKI pin (on the rising edge)
0 = Internal clock (FOSC/4)
bit 0
TMR1ON: Timer1 On bit
1 = Enables Timer1
0 = Stops Timer1
Note 1:
2:
x = Bit is unknown
T1GINV bit inverts the Timer1 gate logic, regardless of source.
TMR1GE bit must be set to use either T1G pin or C2OUT, as selected by the T1GSS bit of the CM2CON1
register, as a Timer1 gate source.
© 2009 Microchip Technology Inc.
DS41291F-page 79
PIC16F882/883/884/886/887
TABLE 6-1:
SUMMARY OF REGISTERS ASSOCIATED WITH TIMER1
Name
Bit 7
Bit 6
Bit 5
Bit 4
CM2CON1
MC1OUT
MC2OUT
C1RSEL
C2RSEL
GIE
PEIE
T0IE
INTE
PIE1
—
ADIE
RCIE
TXIE
PIR1
—
ADIF
RCIF
TXIF
INTCON
Bit 3
Value on
POR, BOR
Value on
all other
Resets
Bit 2
Bit 1
Bit 0
—
—
T1GSS
C2SYNC
0000 --10
0000 --10
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
uuuu uuuu
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
uuuu uuuu
0000 0000
uuuu uuuu
T1CON
Legend:
T1GINV
TMR1GE
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
x = unknown, u = unchanged, – = unimplemented, read as ‘0’. Shaded cells are not used by the Timer1 module.
DS41291F-page 80
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
7.0
TIMER2 MODULE
The Timer2 module is an eight-bit timer with the
following features:
•
•
•
•
•
8-bit timer register (TMR2)
8-bit period register (PR2)
Interrupt on TMR2 match with PR2
Software programmable prescaler (1:1, 1:4, 1:16)
Software programmable postscaler (1:1 to 1:16)
Timer2 is turned on by setting the TMR2ON bit in the
T2CON register to a ‘1’. Timer2 is turned off by clearing
the TMR2ON bit to a ‘0’.
The Timer2 prescaler is controlled by the T2CKPS bits
in the T2CON register. The Timer2 postscaler is
controlled by the TOUTPS bits in the T2CON register.
The prescaler and postscaler counters are cleared
when:
See Figure 7-1 for a block diagram of Timer2.
7.1
The TMR2 and PR2 registers are both fully readable
and writable. On any Reset, the TMR2 register is set to
00h and the PR2 register is set to FFh.
Timer2 Operation
The clock input to the Timer2 module is the system
instruction clock (FOSC/4). The clock is fed into the
Timer2 prescaler, which has prescale options of 1:1,
1:4 or 1:16. The output of the prescaler is then used to
increment the TMR2 register.
• A write to TMR2 occurs.
• A write to T2CON occurs.
• Any device Reset occurs (Power-on Reset, MCLR
Reset, Watchdog Timer Reset, or Brown-out
Reset).
Note:
The values of TMR2 and PR2 are constantly compared
to determine when they match. TMR2 will increment
from 00h until it matches the value in PR2. When a
match occurs, two things happen:
TMR2 is not cleared when T2CON is
written.
• TMR2 is reset to 00h on the next increment cycle
• The Timer2 postscaler is incremented
The match output of the Timer2/PR2 comparator is
then fed into the Timer2 postscaler. The postscaler has
postscale options of 1:1 to 1:16 inclusive. The output of
the Timer2 postscaler is used to set the TMR2IF
interrupt flag bit in the PIR1 register.
FIGURE 7-1:
TIMER2 BLOCK DIAGRAM
TMR2
Output
FOSC/4
Prescaler
1:1, 1:4, 1:16
2
TMR2
Sets Flag
bit TMR2IF
Reset
Comparator
EQ
Postscaler
1:1 to 1:16
T2CKPS<1:0>
PR2
4
TOUTPS<3:0>
© 2009 Microchip Technology Inc.
DS41291F-page 81
PIC16F882/883/884/886/887
REGISTER 7-1:
T2CON: TIMER2 CONTROL REGISTER
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
TOUTPS3
TOUTPS2
TOUTPS1
TOUTPS0
TMR2ON
T2CKPS1
T2CKPS0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
Unimplemented: Read as ‘0’
bit 6-3
TOUTPS<3:0>: Timer2 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
TMR2ON: Timer2 On bit
1 = Timer2 is on
0 = Timer2 is off
bit 1-0
T2CKPS<1:0>: Timer2 Clock Prescale Select bits
00 = Prescaler is 1
01 = Prescaler is 4
1x = Prescaler is 16
TABLE 7-1:
x = Bit is unknown
SUMMARY OF ASSOCIATED TIMER2 REGISTERS
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
1111 1111
1111 1111
0000 0000
0000 0000
-000 0000
-000 0000
PR2
Timer2 Module Period Register
TMR2
Holding Register for the 8-bit TMR2 Register
T2CON
—
Legend:
x = unknown, u = unchanged, — = unimplemented read as ‘0’. Shaded cells are not used for Timer2 module.
DS41291F-page 82
TOUTPS3
TOUTPS2
TOUTPS1
TOUTPS0
TMR2ON
T2CKPS1
T2CKPS0
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
8.0
COMPARATOR MODULE
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
PWM shutdown
Timer1 gate (count enable)
Output synchronization to Timer1 clock input
SR Latch
Programmable and fixed voltage reference
Note:
8.1
Comparator Overview
A single comparator is shown in Figure 8-1 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.
FIGURE 8-1:
SINGLE COMPARATOR
VIN+
+
VIN-
–
Output
VINVIN+
Only Comparator C2 can be linked to
Timer1.
Output
Note:
© 2009 Microchip Technology Inc.
The black areas of the output of the
comparator represents the uncertainty
due to input offsets and response time.
DS41291F-page 83
PIC16F882/883/884/886/887
FIGURE 8-2:
COMPARATOR C1 SIMPLIFIED BLOCK DIAGRAM
C1CH<1:0>
C1POL
2
D
Q1
C12IN0-
0
C12IN1C12IN2-
1
MUX
2
C12IN3-
3
Q
EN
To
Data Bus
RD_CM1CON0
Set C1IF
D
Q3*RD_CM1CON0
Q
EN
CL
To PWM Logic
Reset
C1ON(1)
C1R
C1IN+
FixedRef
CVREF
0
MUX
1
C1VIN- C1
C1VIN+
+
0
MUX
C1VREF
1
C1OUT
C1OUT (to SR Latch)
C1POL
C1RSEL
Note 1:
2:
3:
FIGURE 8-3:
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.
COMPARATOR C2 SIMPLIFIED BLOCK DIAGRAM
C2POL
D
Q1
Q
EN
RD_CM2CON0
C2CH<1:0>
Set C2IF
2
D
Q3*RD_CM2CON0
C2ON(1)
C12IN0-
0
C12IN1C12IN2-
1
MUX
2
C12IN3-
3
CVREF
EN
CL
Reset
C2VINC2VIN+
C2OUT
C2
C2POL
D
FixedRef
Q
C2SYNC
C2R
C2IN+
To
Data Bus
0
MUX
1
From Timer1
Clock
Q
0
MUX
1
SYNCC2OUT
To Timer1 Gate, SR Latch,
PWM Logic, and other
peripherals
0
MUX
C2VREF
1
C2RSEL
Note 1:
2:
3:
DS41291F-page 84
When C2ON = 0, the C2 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.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
8.2
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
8-1 and 8-2, respectively) contain the control and Status
bits for the following:
•
•
•
•
•
Enable
Input selection
Reference selection
Output selection
Output polarity
8.2.1
COMPARATOR ENABLE
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.
8.2.2
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:
8.2.3
To use CxIN+ and CxIN- pins as analog
inputs, the appropriate bits must be set in
the ANSEL and ANSELH registers 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 8.10 “Comparator Voltage Reference” for
more information on the internal voltage reference
module.
8.2.4
Note 1: The CxOE bit overrides the PORT data
latch. Setting the CxON has no impact on
the port override.
2: The internal output of the comparator is
latched with each instruction cycle.
Unless otherwise specified, external
outputs are not latched.
8.2.5
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.
Table 8-1 shows the output state versus input
conditions, including polarity control.
TABLE 8-1:
COMPARATOR OUTPUT
STATE VS. INPUT
CONDITIONS
Input Condition
CxPOL
CxOUT
CxVIN- > CxVIN+
0
0
CxVIN- < CxVIN+
0
1
CxVIN- > CxVIN+
1
1
CxVIN- < CxVIN+
1
0
8.3
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 17.0
“Electrical Specifications” for more details.
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:
• CxOE bit of the CMxCON0 register must be set
• Corresponding TRIS bit must be cleared
• CxON bit of the CMxCON0 register must be set
© 2009 Microchip Technology Inc.
DS41291F-page 85
PIC16F882/883/884/886/887
8.4
Comparator Interrupt Operation
The comparator interrupt flag can 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 Figures 8-2 and 8-3). One latch is updated
with the comparator output level when the CMxCON0
register is read. This latch retains the value until the
next read of the CMxCON0 register or the occurrence
of a Reset. The other latch of the mismatch circuit is
updated on every Q1 system clock. A mismatch
condition will occur when a comparator output change
is clocked through the second latch on the Q1 clock
cycle. At this point the two mismatch latches have
opposite output levels which is detected by the
exclusive-or gate and fed to the interrupt circuitry. The
mismatch condition persists until either the CMxCON0
register is read 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.
FIGURE 8-4:
COMPARATOR
INTERRUPT TIMING W/O
CMxCON0 READ
Q1
Q3
CIN+
TRT
CxOUT
Set CxIF (level)
CxIF
reset by software
FIGURE 8-5:
COMPARATOR
INTERRUPT TIMING WITH
CMxCON0 READ
Q1
Q3
CxIN+
TRT
CxOUT
Set CxIF (level)
CxIF
cleared by CMxCON0 read
reset by software
2: Comparator interrupts will operate correctly
regardless of the state of CxOE.
The comparator interrupt is set by the mismatch edge
and not the mismatch level. This means that the interrupt flag can be reset without the additional step of
reading or writing the CMxCON0 register to clear the
mismatch registers. 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.
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 of the PIR2 register
interrupt flag may not get set.
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 μs for bias settling then clear
the mismatch condition and interrupt flags
before enabling comparator interrupts.
The CxIF bit of the PIR2 register is the comparator
interrupt flag. This bit must be reset in software by
clearing it to ‘0’. Since it is also possible to write a ‘1’ to
this register, an interrupt can be generated.
The CxIE bit of the PIE2 register and the PEIE and GIE
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.
DS41291F-page 86
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
8.5
Operation During Sleep
The comparator, if enabled before entering Sleep mode,
remains active during Sleep. The additional current
consumed by the comparator is shown separately in the
Section 17.0 “Electrical Specifications”. 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.
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 bit of the INTCON register must be set.
The instruction following the Sleep instruction always
executes following a wake from Sleep. If the GIE bit of
the INTCON register is also set, the device will then
execute the Interrupt Service Routine.
8.6
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.
© 2009 Microchip Technology Inc.
DS41291F-page 87
PIC16F882/883/884/886/887
REGISTER 8-1:
CM1CON0: COMPARATOR C1 CONTROL REGISTER 0
R/W-0
R-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
R/W-0
C1ON
C1OUT
C1OE
C1POL
—
C1R
C1CH1
C1CH0
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
Unimplemented: Read as ‘0’
bit 2
C1R: Comparator C1 Reference Select bit (non-inverting input)
1 = C1VIN+ connects to C1VREF output
0 = C1VIN+ connects to C1IN+ 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.
DS41291F-page 88
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 8-2:
CM2CON0: COMPARATOR C2 CONTROL REGISTER 0
R/W-0
R-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
R/W-0
C2ON
C2OUT
C2OE
C2POL
—
C2R
C2CH1
C2CH0
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
Unimplemented: Read as ‘0’
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.
© 2009 Microchip Technology Inc.
DS41291F-page 89
PIC16F882/883/884/886/887
8.7
Analog Input Connection
Considerations
A simplified circuit for an analog input is shown in
Figure 8-6. 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 kΩ 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 8-6:
ANALOG INPUT MODEL
VDD
VT ≈ 0.6V
Rs < 10K
To ADC Input
AIN
VA
RIC
CPIN
5 pF
VT ≈ 0.6V
ILEAKAGE(1)
±500 nA
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 17.0 “Electrical Specifications”.
DS41291F-page 90
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
8.8
Additional Comparator Features
8.8.2
There are three additional comparator features:
• Timer1 count enable (gate)
• Synchronizing output with Timer1
• Simultaneous read of comparator outputs
8.8.1
COMPARATOR C2 GATING TIMER1
This feature can be used to time the duration or interval
of analog events. Clearing the T1GSS bit of the
CM2CON1 register will enable Timer1 to increment
based on the output of Comparator C2. This requires
that Timer1 is on and gating is enabled. See
Section 6.0 “Timer1 Module with Gate Control” for
details.
It is recommended to synchronize the comparator with
Timer1 by setting the C2SYNC bit when the comparator
is used as the Timer1 gate source. This ensures Timer1
does not miss an increment if the comparator changes
during an increment.
SYNCHRONIZING COMPARATOR
C2 OUTPUT TO TIMER1
The Comparator C2 output can be synchronized with
Timer1 by setting the C2SYNC bit of the CM2CON1
register. When enabled, the C2 output is latched on the
falling edge of the Timer1 clock source. If a prescaler is
used with Timer1, the comparator output is latched after
the prescaling function. To prevent a race condition, the
comparator output is latched on the falling edge of the
Timer1 clock source and Timer1 increments on the
rising edge of its clock source. See the Comparator
Block Diagram (Figures 8-2 and 8-3) and the Timer1
Block Diagram (Figure 6-1) for more information.
8.8.3
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.
REGISTER 8-3:
CM2CON1: COMPARATOR C2 CONTROL REGISTER 1
R-0
R-0
R/W-0
R/W-0
U-0
U-0
R/W-1
R/W-0
MC1OUT
MC2OUT
C1RSEL
C2RSEL
—
—
T1GSS
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
x = Bit is unknown
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 = CVREF routed to C1VREF input of Comparator C1
0 = Absolute voltage reference (0.6) routed to C1VREF input of Comparator C1 (or 1.2V precision
reference on parts so equipped)
bit 4
C2RSEL: Comparator C2 Reference Select bit
1 = CVREF routed to C2VREF input of Comparator C2
0 = Absolute voltage reference (0.6) routed to C2VREF input of Comparator C2 (or 1.2V precision
reference on parts so equipped)
bit 3-2
Unimplemented: Read as ‘0’
bit 1
T1GSS: Timer1 Gate Source Select bit
1 = Timer1 gate source is T1G
0 = Timer1 gate source is SYNCC2OUT.
bit 0
C2SYNC: Comparator C2 Output Synchronization bit
1 = Output is synchronous to falling edge of Timer1 clock
0 = Output is asynchronous
© 2009 Microchip Technology Inc.
DS41291F-page 91
PIC16F882/883/884/886/887
8.9
8.9.2
Comparator SR Latch
The SR<1:0> bits of the SRCON register control the
latch output multiplexers and determine four possible
output configurations. In these four configurations, the
CxOUT I/O port logic is connected to:
The SR latch module provides additional control of the
comparator outputs. The module consists of a single
SR latch and output multiplexers. The SR latch can be
set, reset or toggled by the comparator outputs. The SR
latch may also be set or reset, independent of
comparator output, by control bits in the SRCON control
register. The SR latch output multiplexers select
whether the latch outputs or the comparator outputs are
directed to the I/O port logic for eventual output to a pin.
8.9.1
•
•
•
•
C1OUT and C2OUT
C1OUT and SR latch Q
C2OUT and SR latch Q
SR latch Q and Q
After any Reset, the default output configuration is the
unlatched C1OUT and C2OUT mode. This maintains
compatibility with devices that do not have the SR latch
feature.
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. Each latch input is connected to a
comparator output and a software controlled pulse
generator. The latch can be set by C1OUT or the PULSS
bit of the SRCON register. The latch can be reset by
C2OUT or the PULSR bit of the SRCON register. The
latch is reset-dominant, therefore, if both Set and Reset
inputs are high the latch will go to the Reset state. Both
the PULSS and PULSR 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.
FIGURE 8-7:
LATCH OUTPUT
The applicable TRIS bits of the corresponding ports
must be cleared to enable the port pin output drivers.
Additionally, the CxOE comparator output enable bits of
the CMxCON0 registers must be set in order to make the
comparator or latch outputs available on the output pins.
The latch configuration enable states are completely
independent of the enable states for the comparators.
SR LATCH SIMPLIFIED BLOCK DIAGRAM
SR0
C1OE
PULSS
Pulse
Gen(2)
C1OUT (from comparator)
S
0
MUX
1
Q
C1OUT pin(3)
C1SEN
SR
Latch(1)
C2OE
SYNCC2OUT (from comparator)
R
C2REN
PULSR
Note 1:
2:
3:
Pulse
Gen(2)
1
MUX
0
Q
C2OUT pin(3)
SR1
If R = 1 and S = 1 simultaneously, Q = 0, Q = 1
Pulse generator causes a 1/2 Q-state (1 Tosc) pulse width.
Output shown for reference only. See I/O port pin block diagram for more detail.
DS41291F-page 92
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 8-4:
SRCON: SR LATCH CONTROL REGISTER
R/W-0
R/W-0
(2)
(2)
SR1
SR0
R/W-0
R/W-0
R/S-0
R/S-0
U-0
R/W-0
C1SEN
C2REN
PULSS
PULSR
—
FVREN
bit 7
bit 0
Legend:
S = Bit is set only -
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
SR1: SR Latch Configuration bit(2)
1 = C2OUT pin is the latch Q output
0 = C2OUT pin is the C2 comparator output
bit 6
SR0: SR Latch Configuration bits(2)
1 = C1OUT pin is the latch Q output
0 = C1OUT pin is the C1 Comparator output
bit 5
C1SEN: C1 Set Enable bit
1 = C1 comparator output sets SR latch
0 = C1 comparator output has no effect on SR latch
bit 4
C2REN: C2 Reset Enable bit
1 = C2 comparator output resets SR latch
0 = C2 comparator output has no effect on SR latch
bit 3
PULSS: Pulse the SET Input of the SR Latch bit
1 = Triggers pulse generator to set SR latch. Bit is immediately reset by hardware.
0 = Does not trigger pulse generator
bit 2
PULSR: Pulse the Reset Input of the SR Latch bit
1 = Triggers pulse generator to reset SR latch. Bit is immediately reset by hardware.
0 = Does not trigger pulse generator
bit 1
Unimplemented: Read as ‘0’
bit 0
FVREN: Fixed Voltage Reference Enable bit
1 = 0.6V Reference FROM INTOSC LDO is enabled
0 = 0.6V Reference FROM INTOSC LDO is disabled
Note 1:
2:
The CxOUT bit in the CMxCON0 register will always reflect the actual comparator output (not the level on
the pin), regardless of the SR latch operation.
To enable an SR Latch output to the pin, the appropriate CxOE and TRIS bits must be properly
configured.
© 2009 Microchip Technology Inc.
DS41291F-page 93
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8.10
Comparator Voltage Reference
8.10.3
OUTPUT CLAMPED TO VSS
The comparator voltage reference module provides an
internally generated voltage reference for the comparators. The following features are available:
The CVREF output voltage can be set to Vss with no
power consumption by clearing the FVREN bit of the
VRCON register.
•
•
•
•
•
This allows the comparator to detect a zero-crossing
while not consuming additional CVREF module current.
Independent from Comparator operation
Two 16-level voltage ranges
Output clamped to VSS
Ratiometric with VDD
Fixed Reference (0.6V)
Note:
The VRCON register (Register 8-5) controls the
voltage reference module shown in Figure 8-8.
The voltage source is selectable through both ends of
the 16 connection resistor ladder network. Bit VRSS of
the VRCON register selects either the internal or
external voltage source.
The PIC16F882/883/884/886/887 allows the CVREF
signal to be output to the RA2 pin of PORTA under
certain configurations only. For more details, see
Figure 8-9.
8.10.1
INDEPENDENT OPERATION
The comparator voltage reference is independent of
the comparator configuration. Setting the VREN bit of
the VRCON register will enable the voltage reference.
8.10.2
OUTPUT VOLTAGE SELECTION
The CVREF voltage reference has 2 ranges with 16
voltage levels in each range. Range selection is
controlled by the VRR bit of the VRCON register. The
16 levels are set with the VR<3:0> bits of the VRCON
register.
The CVREF output voltage is determined by the following
equations:
EQUATION 8-1:
CVREF OUTPUT VOLTAGE
V RR = 1 (low range):
CVREF = (VR<3:0>/24) × V LADDER
V RR = 0 (high range):
CV REF = (VLADDER/4) + (VR<3:0> × VLADDER/32)
V LADDER = V DD or ([VREF+] - [VREF-]) or VREF+
The full range of VSS to VDD cannot be realized due to
the construction of the module. See Figure 8-8.
8.10.4
Depending on the application, additional
components may be required for a zero
cross circuit. Reference TB3013, “Using
the ESD Parasitic Diodes on Mixed Signal
Microcontrollers” (DS93013), for more
information.
OUTPUT RATIOMETRIC TO VDD
The comparator voltage reference is VDD derived and
therefore, the CVREF output changes with fluctuations in
VDD. The tested absolute accuracy of the Comparator
Voltage Reference can be found in Section 17.0
“Electrical Specifications”.
8.10.5
FIXED VOLTAGE REFERENCE
The fixed voltage reference is independent of VDD, with
a nominal output voltage of 0.6V. This reference can be
enabled by setting the FVREN bit of the SRCON
register to ‘1’. This reference is always enabled when
the HFINTOSC oscillator is active.
8.10.6
FIXED VOLTAGE REFERENCE
STABILIZATION PERIOD
When the fixed voltage reference module is enabled, it
will require some time for the reference and its amplifier
circuits to stabilize. The user program must include a
small delay routine to allow the module to settle. See
Section 17.0 “Electrical Specifications” for the
minimum delay requirement.
8.10.7
VOLTAGE REFERENCE
SELECTION
Multiplexers on the output of the voltage reference
module enable selection of either the CVREF or fixed
voltage reference for use by the comparators.
Setting the C1RSEL bit of the CM2CON1 register
enables current to flow in the CVREF voltage divider
and selects the CVREF voltage for use by C1. Clearing
the C1RSEL bit selects the fixed voltage for use by C1.
Setting the C2RSEL bit of the CM2CON1 register
enables current to flow in the CVREF voltage divider
and selects the CVREF voltage for use by C2. Clearing
the C2RSEL bit selects the fixed voltage for use by C2.
When both the C1RSEL and C2RSEL bits are cleared,
current flow in the CVREF voltage divider is disabled
minimizing the power drain of the voltage reference
peripheral.
DS41291F-page 94
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 8-8:
COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
16 Stages
VREF+
VRSS = 1
8R
R
R
R
R
VRSS = 0
VRR
8R
VDD
Analog
MUX
VREFVRSS = 1
15
CVREF
VRSS = 0
To Comparators
and ADC Module
0
VR<3:0>
VROE
4
VREN
C1RSEL
C2RSEL
CVREF
FVREN
Sleep
HFINTOSC enable
FixedRef
EN
Fixed Voltage
Reference
0.6V
To Comparators
and ADC Module
FIGURE 8-9:
COMPARATOR AND ADC VOLTAGE REFERENCE BLOCK DIAGRAM
VREF+
AVDD
AVDD
1
1
0
0
VCFG0
VRSS
CVREF
Comparator
Voltage
Reference
VROE
ADC
Voltage
Reference
VCFG1
VRSS
0
0
AVSS
1
AVSS
1
VCFG1
VREF-
© 2009 Microchip Technology Inc.
DS41291F-page 95
PIC16F882/883/884/886/887
TABLE 8-2:
COMPARATOR AND ADC VOLTAGE REFERENCE PRIORITY
RA3
RA2
Comp.
Reference (+)
Comp.
Reference (-)
ADC
Reference (+)
ADC
Reference (-)
CFG1
CFG0
VRSS
VROE
I/O
I/O
AVDD
AVSS
AVDD
AVSS
0
0
0
0
I/O
CVREF
AVDD
AVSS
AVDD
AVSS
0
0
0
1
VREF+
VREF-
VREF+
VREF-
AVDD
AVSS
0
0
1
0
VREF+
CVREF
VREF+
AVSS
AVDD
AVSS
0
0
1
1
VREF+
I/O
AVDD
AVSS
VREF+
AVSS
0
1
0
0
VREF+
CVREF
AVDD
AVSS
VREF+
AVSS
0
1
0
1
VREF+
VREF-
VREF+
VREF-
VREF+
AVSS
0
1
1
0
VREF+
CVREF
VREF+
AVSS
VREF+
AVSS
0
1
1
1
I/O
VREF-
AVDD
AVSS
AVDD
VREF-
1
0
0
0
1
I/O
VREF-
AVDD
AVSS
AVDD
VREF-
1
0
0
VREF+
VREF-
VREF+
VREF-
AVDD
VREF-
1
0
1
0
VREF+
VREF-
VREF+
VREF-
AVDD
VREF-
1
0
1
1
VREF+
VREF-
AVDD
AVSS
VREF+
VREF-
1
1
0
0
VREF+
VREF-
AVDD
AVSS
VREF+
VREF-
1
1
0
1
VREF+
VREF-
VREF+
VREF-
VREF+
VREF-
1
1
1
0
VREF+
VREF-
VREF+
VREF-
VREF+
VREF-
1
1
1
1
DS41291F-page 96
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 8-5:
VRCON: VOLTAGE REFERENCE 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-0
VREN
VROE
VRR
VRSS
VR3
VR2
VR1
VR0
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
VREN: Comparator C1 Voltage Reference Enable bit
1 = CVREF circuit powered on
0 = CVREF circuit powered down
bit 6
VROE: Comparator C2 Voltage Reference Enable bit
1 = CVREF voltage level is also output on the RA2/AN2/VREF-/CVREF/C2IN+ pin
0 = CVREF voltage is disconnected from the RA2/AN2/VREF-/CVREF/C2IN+ pin
bit 5
VRR: CVREF Range Selection bit
1 = Low range
0 = High range
bit 4
VRSS: Comparator VREF Range Selection bit
1 = Comparator Reference Source, CVRSRC = (VREF+) - (VREF-)
0 = Comparator Reference Source, CVRSRC = VDD - VSS
bit 3-0
VR<3:0>: CVREF Value Selection 0 ≤ VR<3:0> ≤ 15
When VRR = 1: CVREF = (VR<3:0>/24) * VDD
When VRR = 0: CVREF = VDD/4 + (VR<3:0>/32) * VDD
TABLE 8-3:
Name
ANSEL
ANSELH
CM1CON0
CM2CON0
CM2CON1
INTCON
SUMMARY OF REGISTERS ASSOCIATED WITH THE COMPARATOR AND VOLTAGE
REFERENCE MODULES
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
ANS7
ANS6
ANS5
ANS4
ANS3
ANS2
ANS1
ANS0
1111 1111
1111 1111
—
—
ANS13
ANS12
ANS11
ANS10
ANS9
ANS8
--11 1111
--11 1111
C1ON
C1OUT
C1OE
C1POL
—
C1R
C1CH1
C1CH0
0000 -000
0000 -000
C2ON
C2OUT
C2OE
C2POL
—
C2R
C2CH1
C2CH0
0000 -000
0000 -000
MC1OUT MC2OUT C1RSEL C2RSEL
—
—
T1GSS
C2SYNC
0000 --10
0000 --10
0000 000x
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
PIE2
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
0000 00-0
PIR2
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
0000 00-0
0000 00-0
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
xxxx xxxx
uuuu uuuu
PORTA
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
uuuu uuuu
SRCON
SR1
SR0
C1SEN
C2SEN
PULSS
PULSR
—
FVREN
0000 00-0
0000 00-0
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
1111 1111
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111
1111 1111
VREN
VROE
VRR
VRSS
VR3
VR2
VR1
VR0
0000 0000
0000 0000
VRCON
Legend:
x = unknown, u = unchanged, – = unimplemented, read as ‘0’. Shaded cells are not used for comparator.
© 2009 Microchip Technology Inc.
DS41291F-page 97
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 98
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
9.0
ANALOG-TO-DIGITAL
CONVERTER (ADC) MODULE
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).
The ADC voltage reference is software selectable to be
either internally generated or externally supplied.
The ADC can generate an interrupt upon completion of
a conversion. This interrupt can be used to wake-up the
device from Sleep.
Figure 9-1 shows the block diagram of the ADC.
FIGURE 9-1:
ADC BLOCK DIAGRAM
VCFG1 = 0
AVSS
VREF-
VCFG1 = 1
AVDD
VCFG0 = 0
VREF+
AN0
0000
AN1
0001
AN2
0010
AN3
0011
AN4
0100
AN5
0101
AN6
0110
AN7
0111
AN8
1000
AN9
1001
AN10
1010
AN11
1011
AN12
1100
AN13
1101
CVREF
1110
FixedRef
1111
VCFG0 = 1
ADC
10
GO/DONE
ADFM
0 = Left Justify
1 = Right Justify
10
ADON
VSS
ADRESH
ADRESL
CHS<3:0>
© 2009 Microchip Technology Inc.
DS41291F-page 99
PIC16F882/883/884/886/887
9.1
ADC Configuration
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
9.1.1
PORT CONFIGURATION
The ADC can be used to convert both analog and digital
signals. When converting analog signals, the I/O pin
should be configured for analog by setting the associated
TRIS and ANSEL bits. See the corresponding Port
section for more information.
Note:
9.1.2
Analog voltages on any pin that is defined
as a digital input may cause the input
buffer to conduct excess current.
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 9.2
“ADC Operation” for more information.
DS41291F-page 100
9.1.3
ADC VOLTAGE REFERENCE
The VCFG bits of the ADCON0 register provide
independent control of the positive and negative
voltage references. The positive voltage reference can
be either VDD or an external voltage source. Likewise,
the negative voltage reference can be either VSS or an
external voltage source.
9.1.4
CONVERSION CLOCK
The source of the conversion clock is software selectable via the ADCS bits of the ADCON0 register. There
are four possible clock options:
•
•
•
•
FOSC/2
FOSC/8
FOSC/32
FRC (dedicated internal oscillator)
The time to complete one bit conversion is defined as
TAD. One full 10-bit conversion requires 11 TAD periods
as shown in Figure 9-2.
For correct conversion, the appropriate TAD specification
must be met. See A/D conversion requirements in
Section 17.0 “Electrical Specifications” for more
information. Table 9-1 gives examples of appropriate
ADC clock selections.
Note:
Unless using the FRC, any changes in the
system clock frequency will change the
ADC clock frequency, which may
adversely affect the ADC result.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 9-1:
ADC CLOCK PERIOD (TAD) VS. DEVICE OPERATING FREQUENCIES (VDD > 3.0V)
ADC Clock Period (TAD)
ADC Clock Source
Device Frequency (FOSC)
ADCS<1:0>
FOSC/2
20 MHz
00
FOSC/8
01
8 MHz
100 ns
(2)
250 ns
400 ns
(2)
1.0 μs
500 ns
10
1.6 μs
4.0 μs
FRC
11
2-6 μs(1,4)
2-6 μs(1,4)
(2)
2.0 μs
(2)
FOSC/32
Legend:
Note 1:
2:
3:
4:
4 MHz
(2)
8.0 μs
(3)
2-6 μs(1,4)
1 MHz
2.0 μs
8.0 μs(3)
32.0 μs(3)
2-6 μs(1,4)
Shaded cells are outside of recommended range.
The FRC source has a typical TAD time of 4 μs for VDD > 3.0V.
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.
FIGURE 9-2:
ANALOG-TO-DIGITAL CONVERSION TAD CYCLES
TCY to TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
Conversion Starts
Holding Capacitor is Disconnected from Analog Input (typically 100 ns)
Set GO/DONE bit
9.1.5
ADRESH and ADRESL registers are loaded,
GO bit is cleared,
ADIF bit is set,
Holding capacitor is connected to analog input
INTERRUPTS
The ADC module allows for the ability to generate an
interrupt upon completion of an Analog-to-Digital
conversion. The ADC interrupt flag is the ADIF bit in the
PIR1 register. The ADC interrupt enable is the ADIE bit
in the PIE1 register. The ADIF bit must be cleared in
software.
Note:
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.
Please see Section 14.3 “Interrupts” for more
information.
© 2009 Microchip Technology Inc.
DS41291F-page 101
PIC16F882/883/884/886/887
9.1.6
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 ADCON0 register controls the output format.
Figure 9-3 shows the two output formats.
FIGURE 9-3:
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’
9.2
9.2.1
ADC Operation
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 start the
Analog-to-Digital conversion.
Note:
9.2.2
The GO/DONE bit should not be set in the
same instruction that turns on the ADC.
Refer to Section 9.2.6 “A/D Conversion
Procedure”.
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
9.2.3
TERMINATING A CONVERSION
If a conversion must be terminated before completion,
the GO/DONE bit can be cleared in 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. Additionally, a 2 TAD delay is required before another acquisition can be initiated. Following this delay, an input
acquisition is automatically started on the selected
channel.
Note:
bit 0
bit 7
bit 0
10-bit A/D Result
9.2.4
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.
9.2.5
SPECIAL EVENT TRIGGER
The ECCP Special Event Trigger allows periodic ADC
measurements without software intervention. When
this trigger occurs, the GO/DONE bit is set by hardware
and the Timer1 counter resets to zero.
Using the Special Event Trigger does not assure proper
ADC timing. It is the user’s responsibility to ensure that
the ADC timing requirements are met.
See Section 11.0 “Capture/Compare/PWM Modules
(CCP1 and CCP2)” for more information.
A device Reset forces all registers to their
Reset state. Thus, the ADC module is
turned off and any pending conversion is
terminated.
DS41291F-page 102
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
9.2.6
A/D CONVERSION PROCEDURE
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
• 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).
EXAMPLE 9-1:
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.
;
BANKSEL
ADCON1
;
MOVLW
B’10000000’ ;right justify
MOVWF
ADCON1
;Vdd and Vss as Vref
BANKSEL
TRISA
;
BSF
TRISA,0
;Set RA0 to input
BANKSEL
ANSEL
;
BSF
ANSEL,0
;Set RA0 to analog
BANKSEL
ADCON0
;
MOVLW
B’11000001’ ;ADC Frc clock,
MOVWF
ADCON0
;AN0, On
CALL
SampleTime
;Acquisiton delay
BSF
ADCON0,GO
;Start conversion
BTFSC
ADCON0,GO
;Is conversion done?
GOTO
$-1
;No, test again
BANKSEL
ADRESH
;
MOVF
ADRESH,W
;Read upper 2 bits
MOVWF
RESULTHI
;store in GPR space
BANKSEL
ADRESL
;
MOVF
ADRESL,W
;Read lower 8 bits
MOVWF
RESULTLO
;Store in GPR space
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: See Section 9.3
Requirements”.
© 2009 Microchip Technology Inc.
“A/D
Acquisition
DS41291F-page 103
PIC16F882/883/884/886/887
9.2.7
ADC REGISTER DEFINITIONS
The following registers are used to control the operation of the ADC.
Note:
For ANSEL and ANSELH registers, see
Register 3-3 and Register 3-4, respectively.
REGISTER 9-1:
ADCON0: A/D CONTROL REGISTER 0
R/W-0
R/W-0
ADCS1
ADCS0
R/W-0
CHS3
R/W-0
CHS2
R/W-0
CHS1
R/W-0
CHS0
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 7-6
ADCS<1:0>: A/D Conversion Clock Select bits
00 = FOSC/2
01 = FOSC/8
10 = FOSC/32
11 = FRC (clock derived from a dedicated internal oscillator = 500 kHz max)
bit 5-2
CHS<3:0>: Analog Channel Select bits
0000 = AN0
0001 = AN1
0010 = AN2
0011 = AN3
0100 = AN4
0101 = AN5
0110 = AN6
0111 = AN7
1000 = AN8
1001 = AN9
1010 = AN10
1011 = AN11
1100 = AN12
1101 = AN13
1110 = CVREF
1111 = Fixed Ref (0.6V fixed voltage reference)
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
bit 0
ADON: ADC Enable bit
1 = ADC is enabled
0 = ADC is disabled and consumes no operating current
DS41291F-page 104
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 9-2:
ADCON1: A/D CONTROL REGISTER 1
R/W-0
U-0
R/W-0
R/W-0
U-0
U-0
U-0
U-0
ADFM
—
VCFG1
VCFG0
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
ADFM: A/D Conversion Result Format Select bit
1 = Right justified
0 = Left justified
bit 6
Unimplemented: Read as ‘0’
bit 5
VCFG1: Voltage Reference bit
1 = VREF- pin
0 = VSS
bit 4
VCFG0: Voltage Reference bit
1 = VREF+ pin
0 = VDD
bit 3-0
Unimplemented: Read as ‘0’
© 2009 Microchip Technology Inc.
x = Bit is unknown
DS41291F-page 105
PIC16F882/883/884/886/887
REGISTER 9-3:
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
R/W-x
ADRES9
ADRES8
ADRES7
ADRES6
ADRES5
ADRES4
ADRES3
ADRES2
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 9-4:
ADRESL: ADC RESULT REGISTER LOW (ADRESL) ADFM = 0
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
ADRES1
ADRES0
—
—
—
—
—
—
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 9-5:
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
—
—
—
—
—
—
ADRES9
ADRES8
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 9-6:
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
R/W-x
ADRES7
ADRES6
ADRES5
ADRES4
ADRES3
ADRES2
ADRES1
ADRES0
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
DS41291F-page 106
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
9.3
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 9-4. 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 9-4.
The maximum recommended impedance for analog
sources is 10 kΩ. As the source impedance is
decreased, the acquisition time may be decreased.
After the analog input channel is selected (or changed),
EQUATION 9-1:
an A/D acquisition must be done before the conversion
can be started. To calculate the minimum acquisition
time, Equation 9-1 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 Ω 5.0V V DD
Assumptions:
T ACQ = Amplifier Settling Time + Hold Capacitor Charging Time + Temperature Coefficient
= T AMP + T C + T COFF
= 2µs + T C + [ ( Temperature - 25°C ) ( 0.05µs/°C ) ]
The value for TC can be approximated with the following equations:
1
⎞ = V CHOLD
V AP PLIE D ⎛ 1 – -------------------------n
+
1
⎝
⎠
(2
)–1
;[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 – -------------------------n+1
⎝
⎠
⎝
⎠
(2
)–1
;combining [1] and [2]
Solving for TC:
T C = – C HOLD ( R IC + R SS + R S ) ln(1/2047)
= – 10pF ( 1k Ω + 7k Ω + 10k Ω ) ln(0.0004885)
= 1.37 µs
Therefore:
T ACQ = 2ΜS + 1.37 ΜS + [ ( 50°C- 25°C ) ( 0.05ΜS /°C ) ]
= 4.67 ΜS
Note 1: The reference voltage (VREF) has no effect on the equation, since it cancels itself out.
2: The charge holding capacitor (CHOLD) is not discharged after each conversion.
3: The maximum recommended impedance for analog sources is 10 kΩ. This is required to meet the pin
leakage specification.
© 2009 Microchip Technology Inc.
DS41291F-page 107
PIC16F882/883/884/886/887
FIGURE 9-4:
ANALOG INPUT MODEL
VDD
ANx
Rs
CPIN
5 pF
VA
VT = 0.6V
VT = 0.6V
RIC ≤ 1k
Sampling
Switch
SS Rss
I LEAKAGE(1)
± 500 nA
CHOLD = 10 pF
VSS/VREF-
Legend: CPIN
= Input Capacitance
= Threshold Voltage
VT
I LEAKAGE = Leakage current at the pin due to
various junctions
RIC
= Interconnect Resistance
SS
= Sampling Switch
CHOLD
= Sample/Hold Capacitance
Note 1:
6V
5V
VDD 4V
3V
2V
RSS
5 6 7 8 9 10 11
Sampling Switch
(kΩ)
See Section 17.0 “Electrical Specifications”.
FIGURE 9-5:
ADC TRANSFER FUNCTION
Full-Scale Range
3FFh
3FEh
ADC Output Code
3FDh
3FCh
1 LSB ideal
3FBh
Full-Scale
Transition
004h
003h
002h
001h
000h
Analog Input Voltage
1 LSB ideal
VSS/VREF-
DS41291F-page 108
Zero-Scale
Transition
VDD/VREF+
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 9-2:
Name
SUMMARY OF ASSOCIATED ADC REGISTERS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
ADCON0
ADCS1
ADCS0
CHS3
CHS2
CHS1
CHS0
GO/DONE
ADON
0000 0000
0000 0000
ADCON1
ADFM
—
VCFG1
VCFG0
—
—
—
—
0-00 ----
-000 ----
ANSEL
ANS7
ANS6
ANS5
ANS4
ANS3
ANS2
ANS1
ANS0
1111 1111
1111 1111
—
—
ANS13
ANS12
ANS11
ANS10
ANS9
ANS8
--11 1111
--11 1111
ANSELH
ADRESH
A/D Result Register High Byte
xxxx xxxx
uuuu uuuu
ADRESL
A/D Result Register Low Byte
xxxx xxxx
uuuu uuuu
0000 000x
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
PORTA
RA7
RA6
RA5
RA4
RA3
RA2
RA1
RA0
xxxx xxxx
uuuu uuuu
PORTB
RB7
RB6
RB5
RB4
RB3
RB2
RB1
RB0
xxxx xxxx
uuuu uuuu
PORTE
—
—
—
—
RE3
RE2
RE1
RE0
---- xxxx
---- uuuu
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
1111 1111
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111
1111 111
TRISE
—
—
—
—
TRISE3
TRISE2
TRISE1
TRISE0
---- 1111
---- 111
Legend:
x = unknown, u = unchanged, — = unimplemented read as ‘0’. Shaded cells are not used for ADC module.
© 2009 Microchip Technology Inc.
DS41291F-page 109
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 110
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
10.0
DATA EEPROM AND FLASH
PROGRAM MEMORY
CONTROL
The Data EEPROM and Flash program memory are
readable and writable during normal operation (full VDD
range). These memories are not directly mapped in the
register file space. Instead, they are indirectly
addressed through the Special Function Registers
(SFRs). There are six SFRs used to access these
memories:
•
•
•
•
•
•
EECON1
EECON2
EEDAT
EEDATH
EEADR
EEADRH (bit 4 on PIC16F886/PIC16F887 only)
When interfacing the data memory block, EEDAT holds
the 8-bit data for read/write, and EEADR holds the
address of the EEDAT location being accessed. These
devices have 256 bytes of data EEPROM with an
address range from 0h to 0FFh.
When accessing the program memory block of the
PIC16F886/PIC16F887 devices, the EEDAT and
EEDATH registers form a 2-byte word that holds the
14-bit data for read/write, and the EEADR and
EEADRH registers form a 2-byte word that holds the
12-bit address of the EEPROM location being read.
The PIC16F882 devices have 2K words of program
EEPROM with an address range from 0h to 07FFh.
The PIC16F883/PIC16F884 devices have 4K words of
program EEPROM with an address range from 0h to
0FFFh. The program memory allows one-word reads.
The EEPROM data memory allows byte read and write.
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. The
write/erase voltages are generated by an on-chip
charge pump rated to operate over the voltage range of
the device for byte or word operations.
10.1
EEADR and EEADRH Registers
The EEADR and EEADRH registers can address up to
a maximum of 256 bytes of data EEPROM or up to a
maximum of 8K words of program EEPROM.
When selecting a program address value, the MSB of
the address is written to the EEADRH register and the
LSB is written to the EEADR register. When selecting a
data address value, only the LSB of the address is
written to the EEADR register.
10.1.1
EECON1 AND EECON2 REGISTERS
EECON1 is the control register for EE memory
accesses.
Control bit EEPGD determines if the access will be a program or data memory access. When clear, as it is when
reset, any subsequent operations will operate on the data
memory. When set, any subsequent operations will operate on the program memory. Program memory can only
be read.
Control bits RD and WR initiate read and write,
respectively. These bits cannot be cleared, only set, in
software. They are cleared in hardware at completion
of the read or write operation. The inability to clear the
WR bit in software prevents the accidental, premature
termination of a write operation.
The WREN bit, when set, will allow a write operation to
data EEPROM. On power-up, the WREN bit is clear.
The WRERR bit is set when a write operation is
interrupted by a MCLR or a WDT Time-out Reset
during normal operation. In these situations, following
Reset, the user can check the WRERR bit and rewrite
the location.
Interrupt flag bit EEIF of the PIR2 register is set when
write is complete. It must be cleared in the software.
EECON2 is not a physical register. Reading EECON2
will read all ‘0’s. The EECON2 register is used
exclusively in the data EEPROM write sequence.
Depending on the setting of the Flash Program
Memory Self Write Enable bits WRT<1:0> of the
Configuration Word Register 2, the device may or may
not be able to write certain blocks of the program
memory. However, reads from the program memory
are allowed.
When the device is code-protected, the CPU may
continue to read and write the data EEPROM memory
and Flash program memory. When code-protected, the
device programmer can no longer access data or
program memory.
© 2009 Microchip Technology Inc.
DS41291F-page 111
PIC16F882/883/884/886/887
REGISTER 10-1:
EEDAT: EEPROM DATA REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
EEDAT7
EEDAT6
EEDAT5
EEDAT4
EEDAT3
EEDAT2
EEDAT1
EEDAT0
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
EEDAT<7:0>: 8 Least Significant Address bits to Write to or Read from data EEPROM or Read from program memory
REGISTER 10-2:
EEADR: EEPROM ADDRESS REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
EEADR7
EEADR6
EEADR5
EEADR4
EEADR3
EEADR2
EEADR1
EEADR0
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
EEADR<7:0>: 8 Least Significant Address bits for EEPROM Read/Write Operation(1) or Read from program memory
bit 7-0
REGISTER 10-3:
EEDATH: EEPROM DATA HIGH BYTE REGISTER
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
EEDATH5
EEDATH4
EEDATH3
EEDATH2
EEDATH1
EEDATH0
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
EEDATH<5:0>: 6 Most Significant Data bits from program memory
REGISTER 10-4:
x = Bit is unknown
EEADRH: EEPROM ADDRESS HIGH BYTE REGISTER
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
EEADRH4(1)
EEADRH3
EEADRH2
EEADRH1
EEADRH0
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 4-0
EEADRH<4:0>: Specifies the 4 Most Significant Address bits or high bits for program memory reads
Note 1:
PIC16F886/PIC16F887 only.
DS41291F-page 112
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 10-5:
EECON1: EEPROM CONTROL REGISTER
R/W-x
U-0
U-0
U-0
R/W-x
R/W-0
R/S-0
R/S-0
EEPGD
—
—
—
WRERR
WREN
WR
RD
bit 7
bit 0
Legend:
S = Bit can only be set
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
EEPGD: Program/Data EEPROM Select bit
1 = Accesses program memory
0 = Accesses data memory
bit 6-4
Unimplemented: Read as ‘0’
bit 3
WRERR: EEPROM Error Flag bit
1 = A write operation is prematurely terminated (any MCLR Reset, any WDT Reset during
normal operation or BOR Reset)
0 = The write operation completed
bit 2
WREN: EEPROM Write Enable bit
1 = Allows write cycles
0 = Inhibits write to the data EEPROM
bit 1
WR: Write Control bit
1 = Initiates a write cycle (The bit is cleared by hardware once write is complete. The WR bit can only
be set, not cleared, in software.)
0 = Write cycle to the data EEPROM is complete
bit 0
RD: Read Control bit
1 = Initiates a memory read (the RD is cleared in hardware and can only be set, not cleared, in
software.)
0 = Does not initiate a memory read
© 2009 Microchip Technology Inc.
DS41291F-page 113
PIC16F882/883/884/886/887
10.1.2
READING THE DATA EEPROM
MEMORY
10.1.3
WRITING TO 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 at the very next cycle, in
the EEDAT register; therefore, it can be read in the next
instruction. EEDAT will hold this value until another
read or until it is written to by the user (during a write
operation).
To write an EEPROM data location, the user must first
write the address to the EEADR register and the data
to the EEDAT register. Then the user must follow a
specific sequence to initiate the write for each byte.
EXAMPLE 10-1:
Additionally, the WREN bit in EECON1 must be set to
enable write. This mechanism prevents accidental
writes to data EEPROM due to errant (unexpected)
code execution (i.e., lost programs). The user should
keep the WREN bit clear at all times, except when
updating EEPROM. The WREN bit is not cleared
by hardware.
DATA EEPROM READ
BANKSEL EEADR
MOVLW
DATA_EE_ADDR
MOVWF
EEADR
;
;
;Data Memory
;Address to read
BANKSEL EECON1
;
BCF
EECON1, EEPGD ;Point to DATA memory
BSF
EECON1, RD
;EE Read
BANKSEL EEDAT
;
MOVF
EEDAT, W
;W = EEDAT
BCF
STATUS, RP1
;Bank 0
The write will not initiate if the above sequence is not
followed exactly (write 55h to EECON2, write AAh to
EECON2, then set WR bit) for each byte. Interrupts
should be disabled during this code segment.
After a write sequence has been initiated, clearing the
WREN bit will not affect this write cycle. The WR bit will
be inhibited from being set unless the WREN bit is set.
At the completion of the write cycle, the WR bit is
cleared in hardware and the EE Write Complete
Interrupt Flag bit (EEIF) is set. The user can either
enable this interrupt or poll this bit. EEIF must be
cleared by software.
Required
Sequence
EXAMPLE 10-2:
DATA EEPROM WRITE
BANKSEL
MOVLW
MOVWF
MOVLW
MOVWF
BANKSEL
BCF
BSF
EEADR
DATA_EE_ADDR
EEADR
DATA_EE_DATA
EEDAT
EECON1
EECON1, EEPGD
EECON1, WREN
;
;
;Data Memory Address to write
;
;Data Memory Value to write
;
;Point to DATA memory
;Enable writes
BCF
BTFSC
GOTO
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
INTCON,
INTCON,
$-2
55h
EECON2
AAh
EECON2
EECON1,
INTCON,
GIE
GIE
;Disable INTs.
;SEE AN576
WR
GIE
;
;Write 55h
;
;Write AAh
;Set WR bit to begin write
;Enable INTs.
SLEEP
BCF
BCF
BCF
EECON1, WREN
STATUS, RP0
STATUS, RP1
DS41291F-page 114
;Wait for interrupt to signal write complete
;Disable writes
;Bank 0
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
10.1.4
READING THE FLASH PROGRAM
MEMORY
To read a program memory location, the user must
write the Least and Most Significant address bits to the
EEADR and EEADRH registers, set the EEPGD control bit of the EECON1 register, and then set control bit
RD. Once the read control bit is set, the program memory Flash controller will use the second instruction
cycle to read the data. This causes the second instruction immediately following the “BSF EECON1,RD”
instruction to be ignored. The data is available in the
very next cycle, in the EEDAT and EEDATH registers;
therefore, it can be read as two bytes in the following
instructions.
Required
Sequence
EXAMPLE 10-3:
BANKSEL
MOVLW
MOVWF
MOVLW
MOVWF
BANKSEL
BSF
BSF
EEDAT and EEDATH registers will hold this value until
another read or until it is written to by the user.
Note 1: The two instructions following a program
memory read are required to be NOPs.
This prevents the user from executing a
two-cycle instruction on the next
instruction after the RD bit is set.
2: If the WR bit is set when EEPGD = 1, it
will be immediately reset to ‘0’ and no
operation will take place.
FLASH PROGRAM READ
EEADR
MS_PROG_EE_ADDR
EEADRH
LS_PROG_EE_ADDR
EEADR
EECON1
EECON1, EEPGD
EECON1, RD
;
;
;MS Byte of Program Address to read
;
;LS Byte of Program Address to read
;
;Point to PROGRAM memory
;EE Read
;
;First instruction after BSF EECON1,RD executes normally
NOP
NOP
;Any instructions here are ignored as program
;memory is read in second cycle after BSF EECON1,RD
;
BANKSEL
MOVF
MOVWF
MOVF
MOVWF
BCF
EEDAT
EEDAT, W
LOWPMBYTE
EEDATH, W
HIGHPMBYTE
STATUS, RP1
© 2009 Microchip Technology Inc.
;
;W = LS Byte of Program Memory
;
;W = MS Byte of Program EEDAT
;
;Bank 0
DS41291F-page 115
PIC16F882/883/884/886/887
FIGURE 10-1:
FLASH PROGRAM MEMORY READ CYCLE EXECUTION
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC
Flash ADDR
Flash Data
PC + 1
INSTR (PC)
INSTR(PC - 1)
executed here
EEADRH,EEADR
INSTR (PC + 1)
BSF EECON1,RD
executed here
PC
+3
PC+3
EEDATH,EEDAT
INSTR(PC + 1)
executed here
PC + 5
PC + 4
INSTR (PC + 3)
Forced NOP
executed here
INSTR (PC + 4)
INSTR(PC + 3)
executed here
INSTR(PC + 4)
executed here
RD bit
EEDATH
EEDAT
Register
EERHLT
DS41291F-page 116
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
10.2
Writing to Flash Program Memory
Flash program memory may only be written to if the
destination address is in a segment of memory that is
not write-protected, as defined in bits WRT<1:0> of the
Configuration Word Register 2. Flash program memory
must be written in eight-word blocks (four-word blocks
for 4K memory devices). See Figures 10-2 and 10-3 for
more details. A block consists of eight words with
sequential addresses, with a lower boundary defined
by an address, where EEADR<2:0> = 000. All block
writes to program memory are done as 16-word erase
by eight-word write operations. The write operation is
edge-aligned and cannot occur across boundaries.
After the “BSF EECON1,WR” instruction, the processor
requires two cycles to set up the erase/write operation.
The user must place two NOP instructions after the WR
bit is set. Since data is being written to buffer registers,
the writing of the first seven words of the block appears
to occur immediately. The processor will halt internal
operations for the typical 4 ms, only during the cycle in
which the erase takes place (i.e., the last word of the
sixteen-word block erase). This is not Sleep mode as
the clocks and peripherals will continue to run. After the
eight-word write cycle, the processor will resume operation with the third instruction after the EECON1 write
instruction. The above sequence must be repeated for
the higher eight words.
To write program data, it must first be loaded into the
buffer registers (see Figure 10-2). This is accomplished
by first writing the destination address to EEADR and
EEADRH and then writing the data to EEDATA and
EEDATH. After the address and data have been set up,
then the following sequence of events must be
executed:
1.
2.
3.
Set the EEPGD control bit of the EECON1
register.
Write 55h, then AAh, to EECON2 (Flash
programming sequence).
Set the WR control bit of the EECON1 register.
All eight buffer register locations should be written to
with correct data. If less than eight words are being written to in the block of eight words, then a read from the
program memory location(s) not being written to must
be performed. This takes the data from the program
location(s) not being written and loads it into the
EEDATA and EEDATH registers. Then the sequence of
events to transfer data to the buffer registers must be
executed.
To transfer data from the buffer registers to the program
memory, the EEADR and EEADRH must point to the last
location in the eight-word block (EEADR<2:0> = 111).
Then the following sequence of events must be
executed:
1.
2.
3.
Set the EEPGD control bit of the EECON1
register.
Write 55h, then AAh, to EECON2 (Flash
programming sequence).
Set control bit WR of the EECON1 register to
begin the write operation.
The user must follow the same specific sequence to
initiate the write for each word in the program block,
writing each program word in sequence (000, 001,
010, 011, 100, 101, 110, 111). When the write is
performed on the last word (EEADR<2:0> = 111), a
block of sixteen words is automatically erased and the
content of the eight word buffer registers are written
into the program memory.
© 2009 Microchip Technology Inc.
DS41291F-page 117
PIC16F882/883/884/886/887
FIGURE 10-2:
BLOCK WRITES TO 2K AND 4K FLASH PROGRAM MEMORY
7
5
0
0 7
EEDATH
Sixteen words of
Flash are erased,
then four buffers
are transferred
to Flash
automatically
after this word
is written
EEDATA
6
8
14
14
First word of block
to be written
14
EEADR<1:0> = 00
EEADR<1:0> = 10
EEADR<1:0> = 01
Buffer Register
Buffer Register
14
EEADR<1:0> = 11
Buffer Register
Buffer Register
Program Memory
FIGURE 10-3:
BLOCK WRITES TO 8K FLASH PROGRAM MEMORY
7
5
0 7
EEDATH
0
EEDATA
6
8
14
14
First word of block
to be written
14
EEADR<2:0> = 000
Buffer Register
EEADR<2:0> = 010
EEADR<2:0> = 001
Buffer Register
Buffer Register
Sixteen words of
Flash are erased,
then eight buffers
are transferred
to Flash
automatically
after this word
is written
14
EEADR<2:0> = 111
Buffer Register
Program Memory
DS41291F-page 118
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
An example of the complete eight-word write sequence
is shown in Example 10-4. The initial address is loaded
into the EEADRH and EEADR register pair; the eight
words of data are loaded using indirect addressing.
EXAMPLE 10-4:
LOOP
WRITING TO FLASH PROGRAM MEMORY
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; This write routine assumes the following:
;
A valid starting address (the least significant bits = '000')
;
is loaded in ADDRH:ADDRL
;
ADDRH, ADDRL and DATADDR are all located in data memory
;
BANKSEL EEADRH
MOVF
ADDRH,W
; Load initial address
MOVWF
EEADRH
;
MOVF
ADDRL,W
;
MOVWF
EEADR
;
MOVF
DATAADDR,W ; Load initial data address
MOVWF
FSR
;
MOVF
INDF,W
; Load first data byte into lower
MOVWF
EEDATA
;
INCF
FSR,F
; Next byte
MOVF
INDF,W
; Load second data byte into upper
MOVWF
EEDATH
;
INCF
FSR,F
;
BANKSEL EECON1
BSF
EECON1,EEPGD ; Point to program memory
BSF
EECON1,WREN ; Enable writes
BCF
INTCON,GIE ; Disable interrupts (if using)
BTFSC
INTCON,GIE ; See AN576
GOTO
$-2
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
Required Sequence
MOVLW
55h
; Start of required write sequence:
MOVWF
EECON2
; Write 55h
MOVLW
0AAh
;
MOVWF
EECON2
; Write 0AAh
BSF
EECON1,WR
; Set WR bit to begin write
NOP
; Required to transfer data to the buffer
NOP
; registers
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
BCF
EECON1,WREN ; Disable writes
BSF
INTCON,GIE ; Enable interrupts (comment out if not using interrupts)
BANKSEL EEADR
MOVF
EEADR, W
INCF
EEADR,F
; Increment address
ANDLW
0x0F
; Indicates when sixteen words have been programmed
SUBLW
0x0F
;
0x0F = 16 words
;
0x0B = 12 words (PIC16F884/883/882 only)
;
0x07 = 8 words
;
0x03 = 4 words(PIC16F884/883/882 only)
BTFSS
STATUS,Z
; Exit on a match,
GOTO
LOOP
; Continue if more data needs to be written
© 2009 Microchip Technology Inc.
DS41291F-page 119
PIC16F882/883/884/886/887
10.3
Write Verify
Depending on the application, good programming
practice may dictate that the value written to the data
EEPROM should be verified (see Example 10-5) to the
desired value to be written.
EXAMPLE 10-5:
WRITE VERIFY
BANKSEL EEDAT
MOVF
EEDAT, W
BANKSEL EECON1
BSF
EECON1, RD
BANKSEL
XORWF
BTFSS
GOTO
:
BCF
10.3.1
EEDAT
EEDAT, W
STATUS, Z
WRITE_ERR
STATUS, RP1
;
;EEDAT not changed
;from previous write
;
;YES, Read the
;value written
;
;
;Is data the same
;No, handle error
;Yes, continue
;Bank 0
When the data memory is code-protected, only the
CPU is able to read and write data to the data
EEPROM. It is recommended to code-protect the program memory when code-protecting data memory.
This prevents anyone from programming zeroes over
the existing code (which will execute as NOPs) to reach
an added routine, programmed in unused program
memory, which outputs the contents of data memory.
Programming unused locations in program memory to
‘0’ will also help prevent data memory code protection
from becoming breached.
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 (specification D124) without exceeding the
total number of write cycles to a single byte
(specifications D120 and D120A). If this is the case,
then a refresh of the array must be performed. For this
reason, variables that change infrequently (such as
constants, IDs, calibration, etc.) should be stored in
Flash program memory.
10.4
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 built in. On power-up, WREN is cleared. Also, the
Power-up
Timer
(64 ms
duration)
prevents
EEPROM write.
The write initiate sequence and the WREN bit together
help prevent an accidental write during:
• Brown-out
• Power Glitch
• Software Malfunction
10.5
Data EEPROM Operation During
Code-Protect
Data memory can be code-protected by programming
the CPD bit in the Configuration Word Register 1
(Register 14-1) to ‘0’.
DS41291F-page 120
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 10-1:
Name
EECON1
EECON2
EEADR
EEADRH
EEDAT
SUMMARY OF REGISTERS ASSOCIATED WITH DATA EEPROM
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
EEPGD
—
—
—
WRERR
WREN
WR
RD
x--- x000
0--- q000
---- ----
---- ----
EEPROM Control Register 2 (not a physical register)
EEADR7
EEADR6
EEADR5
EEADR4
—
—
—
EEDAT7
EEDAT6
EEDAT5
EEDAT4
EEADR3
EEADR2
EEADR1
EEADR0
0000 0000
0000 0000
EEADRH2
EEADRH1
EEADRH0
---0 0000
---0 0000
EEDAT3
EEDAT2
EEDAT1
EEDAT0
0000 0000
0000 0000
EEADRH4(1) EEADRH3
EEDATH
—
—
EEDATH5
EEDATH4
EEDATH3
EEDATH2
EEDATH1
EEDATH0
--00 0000
--00 0000
INTCON
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
PIE2
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
0000 00-0
PIR2
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
0000 00-0
0000 00-0
Legend:
Note
1:
x = unknown, u = unchanged, — = unimplemented read as ‘0’, q = value depends upon condition.
Shaded cells are not used by data EEPROM module.
PIC16F886/PIC16F887 only.
© 2009 Microchip Technology Inc.
DS41291F-page 121
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 122
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.0
CAPTURE/COMPARE/PWM
MODULES (CCP1 AND CCP2)
This device contains one Enhanced Capture/Compare/
PWM (CCP1) and Capture/Compare/PWM module
(CCP2). The CCP1 and CCP2 modules are identical in
operation, with the exception of the Enhanced PWM
features available on CCP1 only. See Section 11.6
“PWM (Enhanced Mode)” for more information.
Note:
CCPRx and CCPx throughout this
document refer to CCPR1 or CCPR2 and
CCP1 or CCP2, respectively.
© 2009 Microchip Technology Inc.
DS41291F-page 123
PIC16F882/883/884/886/887
11.1
Enhanced Capture/Compare/PWM
(CCP1)
TABLE 11-1:
The Enhanced Capture/Compare/PWM module is a
peripheral which allows the user to time and control
different events. 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 a Pulse-Width
Modulated signal of varying frequency and duty cycle.
ECCP MODE – TIMER
RESOURCES REQUIRED
ECCP Mode
Timer Resource
Capture
Timer1
Compare
Timer1
PWM
Timer2
Table 11-1 shows the timer resources required by the
ECCP module.
REGISTER 11-1:
CCP1CON: ENHANCED CCP1 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-0
P1M1
P1M0
DC1B1
DC1B0
CCP1M3
CCP1M2
CCP1M1
CCP1M0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
P1M<1:0>: PWM Output Configuration bits
If CCP1M<3:2> = 00, 01, 10:
xx = P1A assigned as Capture/Compare input; P1B, P1C, P1D assigned as port pins
If CCP1M<3:2> = 11:
00 = Single output; P1A modulated; P1B, P1C, P1D assigned as port pins
01 = Full-Bridge output forward; P1D modulated; P1A active; P1B, P1C inactive
10 = Half-Bridge output; P1A, P1B modulated with dead-band control; P1C, P1D assigned as port pins
11 = Full-Bridge output reverse; P1B modulated; P1C active; P1A, P1D inactive
bit 5-4
DC1B<1:0>: PWM Duty Cycle 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 CCPR1L.
bit 3-0
CCP1M<3:0>: ECCP Mode Select bits
0000 = Capture/Compare/PWM off (resets ECCP module)
0001 = Unused (reserved)
0010 = Compare mode, toggle output on match (CCP1IF bit is set)
0011 = Unused (reserved)
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode, set output on match (CCP1IF bit is set)
1001 = Compare mode, clear output on match (CCP1IF bit is set)
1010 = Compare mode, generate software interrupt on match (CCP1IF bit is set, CCP1 pin is
unaffected)
1011 = Compare mode, trigger special event (CCP1IF bit is set; CCP1 resets TMR1 or TMR2
1100 = PWM mode; P1A, P1C active-high; P1B, P1D active-high
1101 = PWM mode; P1A, P1C active-high; P1B, P1D active-low
1110 = PWM mode; P1A, P1C active-low; P1B, P1D active-high
1111 = PWM mode; P1A, P1C active-low; P1B, P1D active-low
DS41291F-page 124
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.2
Capture/Compare/PWM (CCP2)
TABLE 11-2:
The Capture/Compare/PWM module is a peripheral
which allows the user to time and control different
events. 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 a Pulse-Width Modulated signal of
varying frequency and duty cycle.
CCP MODE – TIMER
RESOURCES REQUIRED
CCP Mode
Timer Resource
Capture
Timer1
Compare
Timer1
PWM
Timer2
The timer resources used by the module are shown in
Table 11-2.
Additional information on CCP modules is available in
the Application Note AN594, “Using the CCP Modules”
(DS00594).
REGISTER 11-2:
CCP2CON: CCP2 CONTROL REGISTER
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
DC2B1
DC2B0
CCP2M3
CCP2M2
CCP2M1
CCP2M0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
Unimplemented: Read as ‘0’
bit 5-4
DC2B<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 CCPR2L.
bit 3-0
CCP2M<3:0>: CCP2 Mode Select bits
0000 = Capture/Compare/PWM off (resets CCP2 module)
0001 = Unused (reserved)
0010 = Unused (reserved)
0011 = Unused (reserved)
0100 = Capture mode, every falling edge
0101 = Capture mode, every rising edge
0110 = Capture mode, every 4th rising edge
0111 = Capture mode, every 16th rising edge
1000 = Compare mode, set output on match (CCP2IF bit is set)
1001 = Compare mode, clear output on match (CCP2IF bit is set)
1010 = Compare mode, generate software interrupt on match (CCP2IF bit is set, CCP2 pin
is unaffected)
1011 = Compare mode, trigger special event (CCP2IF bit is set, TMR1 is reset and A/D
conversion is started if the ADC module is enabled. CCP2 pin is unaffected.)
11xx = PWM mode.
© 2009 Microchip Technology Inc.
DS41291F-page 125
PIC16F882/883/884/886/887
11.3
11.3.2
Capture Mode
In Capture mode, the CCPRxH, CCPRxL register pair
captures the 16-bit value of the TMR1 register when an
event occurs on pin CCPx. An event is defined as one
of the following and is configured by the CCP1M<3:0>
bits of the CCP1CON register:
•
•
•
•
Every falling edge
Every rising edge
Every 4th rising edge
Every 16th rising edge
When a capture is made, the Interrupt Request Flag bit
CCPxIF of the PIRx 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 (see Figure 11-1).
11.3.1
CCP PIN CONFIGURATION
In Capture mode, the CCPx pin should be configured
as an input by setting the associated TRIS control bit.
Note:
If the CCPx pin is configured as an output,
a write to the port can cause a capture
condition.
FIGURE 11-1:
Prescaler
÷ 1, 4, 16
CAPTURE MODE
OPERATION BLOCK
DIAGRAM
CCPRxH
and
Edge Detect
11.3.3
SOFTWARE INTERRUPT
When the Capture mode is changed, a false capture
interrupt may be generated. The user should keep the
CCPxIE interrupt enable bit of the PIEx register clear to
avoid false interrupts. Additionally, the user should
clear the CCPxIF interrupt flag bit of the PIRx register
following any change in Operating mode.
11.3.4
CCP PRESCALER
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.
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 (see Example 11-1).
EXAMPLE 11-1:
CLRF
MOVLW
CCPRxL
Capture
Enable
TMR1H
Timer1 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.
CHANGING BETWEEN
CAPTURE PRESCALERS
BANKSEL CCP1CON
Set Flag bit CCPxIF
(PIRx register)
CCPx
pin
TIMER1 MODE SELECTION
MOVWF
;Set Bank bits to point
;to CCP1CON
CCP1CON
;Turn CCP module off
NEW_CAPT_PS ;Load the W reg with
; the new prescaler
; move value and CCP ON
CCP1CON
;Load CCP1CON with this
; value
TMR1L
CCPxCON<3:0>
System Clock (FOSC)
DS41291F-page 126
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.4
11.4.2
Compare Mode
In Compare mode, the 16-bit CCPRx register value is
constantly compared against the TMR1 register pair
value. When a match occurs, the CCPx module may:
•
•
•
•
•
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 11-2:
COMPARE MODE
OPERATION BLOCK
DIAGRAM
CCPxCON<3:0>
Mode Select
Q
S
R
Output
Logic
Match
TRIS
Output Enable
Comparator
TMR1H
TMR1L
Special Event Trigger
Special Event Trigger will:
• Clear TMR1H and TMR1L registers.
• NOT set interrupt flag bit TMR1IF of the PIR1 register.
• Set the GO/DONE bit to start the ADC conversion.
11.4.1
CCP PIN CONFIGURATION
The user must configure the CCPx pin as an output by
clearing the associated TRIS bit.
Note:
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 CCP1CON
register).
11.4.4
SPECIAL EVENT TRIGGER
When Special Event Trigger mode is chosen
(CCPxM<3:0> = 1011), the CCPx module does the
following:
• Resets Timer1
• Starts an ADC conversion if ADC is enabled
The CCPx module does not assert control of the CCPx
pin in this mode (see the CCPxCON register).
Set CCPxIF Interrupt Flag
(PIRx)
4
CCPRxH CCPRxL
CCPx
Pin
In Compare mode, Timer1 must be running in either
Timer mode or Synchronized Counter mode. The
compare operation may not work in Asynchronous
Counter mode.
11.4.3
The action on the pin is based on the value of the
CCPxM<3:0> control bits of the CCPx1CON register.
TIMER1 MODE SELECTION
The Special Event Trigger output of the CCP occurs
immediately upon a match between the TMR1H,
TMR1L register pair and the CCPRxH, CCPRxL
register pair. The TMR1H, TMR1L register pair is not
reset until the next rising edge of the Timer1 clock. This
allows the CCPRxH, CCPRxL register pair to
effectively provide a 16-bit programmable period
register for Timer1.
Note 1: The Special Event Trigger from the CCP
module does not set interrupt flag bit
TMRxIF of the PIR1 register.
2: Removing the match condition by
changing the contents of the CCPRxH
and CCPRxL register pair, between the
clock edge that generates the Special
Event Trigger and the clock edge that
generates the Timer1 Reset, will preclude
the Reset from occurring.
Clearing the CCP1CON register will force
the CCPx compare output latch to the
default low level. This is not the PORT I/O
data latch.
© 2009 Microchip Technology Inc.
DS41291F-page 127
PIC16F882/883/884/886/887
11.5
PWM Mode
The PWM mode generates a Pulse-Width Modulated
signal on the CCPx pin. The duty cycle, period and
resolution are determined by the following registers:
•
•
•
•
PR2
T2CON
CCPRxL
CCPxCON
FIGURE 11-4:
CCP PWM OUTPUT
Period
Pulse Width
In Pulse-Width Modulation (PWM) mode, the CCP
module produces up to a 10-bit resolution PWM output
on the CCPx pin. Since the CCPx pin is multiplexed
with the PORT data latch, the TRIS for that pin must be
cleared to enable the CCPx pin output driver.
Note:
The PWM output (Figure 11-4) has a time base
(period) and a time that the output stays high (duty
cycle).
TMR2 = PR2
TMR2 = CCPRxL:CCPxCON<5:4>
TMR2 = 0
Clearing the CCPxCON register will
relinquish CCPx control of the CCPx pin.
Figure 11-3 shows a simplified block diagram of PWM
operation.
Figure 11-4 shows a typical waveform of the PWM
signal.
For a step-by-step procedure on how to set up the CCP
module for PWM operation, see Section 11.5.7
“Setup for PWM Operation”.
FIGURE 11-3:
SIMPLIFIED PWM BLOCK
DIAGRAM
CCPxCON<5:4>
Duty Cycle Registers
CCPRxL
CCPRxH(2) (Slave)
CCPx
R
Comparator
TMR2
(1)
Q
S
TRIS
Comparator
PR2
Note 1:
2:
Clear Timer2,
toggle CCPx pin and
latch duty cycle
The 8-bit timer TMR2 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.
DS41291F-page 128
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.5.1
PWM PERIOD
The PWM period is specified by the PR2 register of
Timer2. The PWM period can be calculated using the
formula of Equation 11-1.
EQUATION 11-1:
PWM PERIOD
PWM Period = [ ( PR2 ) + 1 ] • 4 • T OSC •
(TMR2 Prescale Value)
Note:
TOSC = 1/FOSC
11.5.2
PWM DUTY CYCLE
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 PR2 and TMR2
registers occurs). While using the PWM, the CCPRxH
register is read-only.
When TMR2 is equal to PR2, the following three events
occur on the next increment cycle:
Equation 11-2 is used to calculate the PWM pulse
width.
• TMR2 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.
Equation 11-3 is used to calculate the PWM duty cycle
ratio.
Note:
EQUATION 11-2:
PULSE WIDTH
Pulse Width = ( CCPRxL:CCPxCON<5:4> ) •
T OSC • (TMR2 Prescale Value)
The Timer2 postscaler (see Section 7.1
“Timer2 Operation”) is not used in the
determination of the PWM frequency.
EQUATION 11-3:
DUTY CYCLE RATIO
( CCPRxL:CCPxCON<5:4> )
Duty Cycle Ratio = ----------------------------------------------------------------------4 ( PR2 + 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 TMR2 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 Timer2 prescaler is set to 1:1.
When the 10-bit time base matches the CCPRxH and
2-bit latch, then the CCPx pin is cleared (see
Figure 11-3).
© 2009 Microchip Technology Inc.
DS41291F-page 129
PIC16F882/883/884/886/887
11.5.3
PWM RESOLUTION
EQUATION 11-4:
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 PR2 is
255. The resolution is a function of the PR2 register
value as shown by Equation 11-4.
TABLE 11-3:
log [ 4 ( PR2 + 1 ) ]
Resolution = ------------------------------------------ bits
log ( 2 )
Note:
If the pulse width value is greater than the
period the assigned PWM pin(s) will
remain unchanged.
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 20 MHz)
PWM Frequency
Timer Prescale (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
TABLE 11-4:
PWM RESOLUTION
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
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS (FOSC = 8 MHz)
PWM Frequency
Timer Prescale (1, 4, 16)
PR2 Value
Maximum Resolution (bits)
DS41291F-page 130
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
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.5.4
OPERATION IN SLEEP MODE
In Sleep mode, the TMR2 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, TMR2 will continue from its
previous state.
11.5.5
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 4.0 “Oscillator Module (With Fail-Safe
Clock Monitor)” for additional details.
11.5.6
11.5.7
The following steps should be taken when configuring
the CCP module for PWM operation:
1.
2.
3.
4.
5.
EFFECTS OF RESET
Any Reset will force all ports to Input mode and the
CCP registers to their Reset states.
6.
© 2009 Microchip Technology Inc.
SETUP FOR PWM OPERATION
Disable the PWM pin (CCPx) output drivers as
an input by setting the associated TRIS bit.
Set the PWM period by loading the PR2 register.
Configure the CCP module for the PWM mode
by loading the CCPxCON register with the
appropriate values.
Set the PWM duty cycle by loading the CCPRxL
register and DCxB<1:0> bits of the CCPxCON
register.
Configure and start Timer2:
• Clear the TMR2IF interrupt flag bit of the
PIR1 register.
• Set the Timer2 prescale value by loading the
T2CKPS bits of the T2CON register.
• Enable Timer2 by setting the TMR2ON bit of
the T2CON register.
Enable PWM output after a new PWM cycle has
started:
• Wait until Timer2 overflows (TMR2IF bit of
the PIR1 register is set).
• Enable the CCPx pin output driver by clearing
the associated TRIS bit.
DS41291F-page 131
PIC16F882/883/884/886/887
11.6
PWM (Enhanced Mode)
The PWM outputs are multiplexed with I/O pins and are
designated P1A, P1B, P1C and P1D. The polarity of the
PWM pins is configurable and is selected by setting the
CCP1M bits in the CCP1CON register appropriately.
The Enhanced PWM Mode can generate a PWM signal
on up to four different output pins with up to 10-bits of
resolution. It can do this through four different PWM
output modes:
•
•
•
•
Table 11-5 shows the pin assignments for each
Enhanced PWM mode.
Single PWM
Half-Bridge PWM
Full-Bridge PWM, Forward mode
Full-Bridge PWM, Reverse mode
Figure 11-5 shows an example of a simplified block
diagram of the Enhanced PWM module.
Note:
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.
To select an Enhanced PWM mode, the P1M bits of the
CCP1CON register must be set appropriately.
Note:
The PWM Enhanced mode is available on
the Enhanced Capture/Compare/PWM
module (CCP1) only.
FIGURE 11-5:
EXAMPLE SIMPLIFIED BLOCK DIAGRAM OF THE ENHANCED PWM MODE
Duty Cycle Registers
DC1B<1:0>
CCP1M<3:0>
4
P1M<1:0>
2
CCPR1L
CCP1/P1A
CCP1/P1A
TRISn
CCPR1H (Slave)
P1B
R
Comparator
Output
Controller
Q
P1B
TRISn
P1C
(1)
TMR2
S
P1D
Comparator
Clear Timer2,
toggle PWM pin and
latch duty cycle
PR2
Note
1:
P1C
TRISn
P1D
TRISn
PWM1CON
The 8-bit timer TMR2 register is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler to create the 10-bit
time base.
Note 1: The TRIS register value for each PWM output must be configured appropriately.
2: Clearing the CCPxCON register will relinquish ECCP control of all PWM output pins.
3: Any pin not used by an Enhanced PWM mode is available for alternate pin functions.
TABLE 11-5:
EXAMPLE PIN ASSIGNMENTS FOR VARIOUS PWM ENHANCED MODES
ECCP Mode
P1M<1:0>
CCP1/P1A
Single
00
Yes(1)
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:
P1B
Yes
(1)
P1C
Yes
(1)
P1D
Yes(1)
Pulse Steering enables outputs in Single mode.
DS41291F-page 132
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 11-6:
EXAMPLE PWM (ENHANCED MODE) OUTPUT RELATIONSHIPS (ACTIVE-HIGH
STATE)
Signal
P1M<1:0>
PR2+1
Pulse
Width
0
Period
00
(Single Output)
P1A Modulated
Delay(1)
Delay(1)
P1A Modulated
10
(Half-Bridge)
P1B Modulated
P1A Active
01
(Full-Bridge,
Forward)
P1B Inactive
P1C Inactive
P1D Modulated
P1A Inactive
11
(Full-Bridge,
Reverse)
P1B Modulated
P1C Active
P1D Inactive
Relationships:
• Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value)
• Pulse Width = TOSC * (CCPR1L<7:0>:CCP1CON<5:4>) * (TMR2 Prescale Value)
• Delay = 4 * TOSC * (PWM1CON<6:0>)
Note 1: Dead-band delay is programmed using the PWM1CON register (Section 11.6.6 “Programmable Dead-Band Delay
Mode”).
© 2009 Microchip Technology Inc.
DS41291F-page 133
PIC16F882/883/884/886/887
FIGURE 11-7:
EXAMPLE ENHANCED PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE)
Signal
P1M<1:0>
PR2+1
Pulse
Width
0
Period
00
(Single Output)
P1A Modulated
P1A Modulated
Delay(1)
10
(Half-Bridge)
Delay(1)
P1B Modulated
P1A Active
01
(Full-Bridge,
Forward)
P1B Inactive
P1C Inactive
P1D Modulated
P1A Inactive
11
(Full-Bridge,
Reverse)
P1B Modulated
P1C Active
P1D Inactive
Relationships:
• Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value)
• Pulse Width = TOSC * (CCPR1L<7:0>:CCP1CON<5:4>) * (TMR2 Prescale Value)
• Delay = 4 * TOSC * (PWM1CON<6:0>)
Note
1:
DS41291F-page 134
Dead-band delay is programmed using the PWM1CON register (Section 11.6.6 “Programmable Dead-Band Delay
Mode”).
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.6.1
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/P1A pin, while the complementary PWM
output signal is output on the P1B pin (see Figure 11-9).
This mode can be used for Half-Bridge applications, as
shown in Figure 11-9, 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 PWM1CON 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 11.6.6 “Programmable Dead-Band Delay
Mode” for more details of the dead-band delay
operations.
Since the P1A and P1B outputs are multiplexed with
the PORT data latches, the associated TRIS bits must
be cleared to configure P1A and P1B as outputs.
FIGURE 11-8:
Period
Period
Pulse Width
P1A(2)
td
td
P1B(2)
(1)
(1)
(1)
td = Dead-Band Delay
Note 1:
2:
FIGURE 11-9:
EXAMPLE OF HALFBRIDGE PWM OUTPUT
At this time, the TMR2 register is equal to the
PR2 register.
Output signals are shown as active-high.
EXAMPLE OF HALF-BRIDGE APPLICATIONS
Standard Half-Bridge Circuit (“Push-Pull”)
FET
Driver
+
P1A
Load
FET
Driver
+
P1B
-
Half-Bridge Output Driving a Full-Bridge Circuit
V+
FET
Driver
FET
Driver
P1A
FET
Driver
Load
FET
Driver
P1B
© 2009 Microchip Technology Inc.
DS41291F-page 135
PIC16F882/883/884/886/887
11.6.2
FULL-BRIDGE MODE
In Full-Bridge mode, all four pins are used as outputs.
An example of Full-Bridge application is shown in
Figure 11-10.
In the Forward mode, pin CCP1/P1A is driven to its active
state, pin P1D is modulated, while P1B and P1C will be
driven to their inactive state as shown in Figure 11-11.
In the Reverse mode, P1C is driven to its active state,
pin P1B is modulated, while P1A and P1D will be driven
to their inactive state as shown Figure 11-11.
P1A, P1B, P1C and P1D outputs are multiplexed with
the PORT data latches. The associated TRIS bits must
be cleared to configure the P1A, P1B, P1C and P1D
pins as outputs.
FIGURE 11-10:
EXAMPLE OF FULL-BRIDGE APPLICATION
V+
FET
Driver
QC
QA
FET
Driver
P1A
Load
P1B
FET
Driver
P1C
FET
Driver
QD
QB
VP1D
DS41291F-page 136
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 11-11:
EXAMPLE OF FULL-BRIDGE PWM OUTPUT
Forward Mode
Period
P1A
(2)
Pulse Width
P1B(2)
P1C(2)
P1D(2)
(1)
(1)
Reverse Mode
Period
Pulse Width
P1A(2)
P1B(2)
P1C(2)
P1D(2)
(1)
Note 1:
2:
(1)
At this time, the TMR2 register is equal to the PR2 register.
Output signal is shown as active-high.
© 2009 Microchip Technology Inc.
DS41291F-page 137
PIC16F882/883/884/886/887
11.6.2.1
Direction Change in Full-Bridge
Mode
In the Full-Bridge mode, the P1M1 bit in the CCP1CON
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 P1M1 bit of the CCP1CON register. The following
sequence occurs prior to the end of the current PWM
period:
• The modulated outputs (P1B and P1D) are placed
in their inactive state.
• The associated unmodulated outputs (P1A and
P1C) are switched to drive in the opposite
direction.
• PWM modulation resumes at the beginning of the
next period.
See Figure 11-12 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 11-13 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 P1A and
P1D become inactive, while output P1C 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 11-10) 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 11-12:
EXAMPLE OF PWM DIRECTION CHANGE
Period(1)
Signal
Period
P1A (Active-High)
P1B (Active-High)
Pulse Width
P1C (Active-High)
(2)
P1D (Active-High)
Pulse Width
Note 1:
2:
The direction bit P1M1 of the CCP1CON register is written any time during the PWM cycle.
When changing directions, the P1A and P1C signals switch before the end of the current PWM cycle. The
modulated P1B and P1D signals are inactive at this time. The length of this time is (1/Fosc) • TMR2 prescale
value.
DS41291F-page 138
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 11-13:
EXAMPLE OF PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE
Forward Period
t1
Reverse Period
P1A
P1B
PW
P1C
P1D
PW
TON
External Switch C
TOFF
External Switch D
Potential
Shoot-Through Current
Note 1:
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.
© 2009 Microchip Technology Inc.
DS41291F-page 139
PIC16F882/883/884/886/887
11.6.3
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.
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 CCP1M<1:0> bits of the CCP1CON register allow
the user to choose whether the PWM output signals are
active-high or active-low for each pair of PWM output pins
(P1A/P1C and P1B/P1D). The PWM output polarities
must be selected before the PWM 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.
The P1A, P1B, P1C and P1D 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
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 TMR2IF bit of the PIR1 register
being set as the second PWM period begins.
DS41291F-page 140
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
11.6.4
ENHANCED PWM AUTOSHUTDOWN MODE
A shutdown condition is indicated by the ECCPASE
(Auto-Shutdown Event Status) bit of the ECCPAS
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.
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.
When a shutdown event occurs, two things happen:
The ECCPASE bit is set to ‘1’. The ECCPASE will
remain set until cleared in firmware or an auto-restart
occurs (see Section 11.6.5 “Auto-Restart Mode”).
The auto-shutdown sources are selected using the
ECCPAS<2:0> bits of the ECCPAS register. A shutdown
event may be generated by:
•
•
•
•
The enabled PWM pins are asynchronously placed in
their shutdown states. The PWM output pins are
grouped into pairs [P1A/P1C] and [P1B/P1D]. The state
of each pin pair is determined by the PSSAC and
PSSBD bits of the ECCPAS register. Each pin pair may
be placed into one of three states:
A logic ‘0’ on the INT pin
Comparator C1
Comparator C2
Setting the ECCPASE bit in firmware
FIGURE 11-14:
• Drive logic ‘1’
• Drive logic ‘0’
• Tri-state (high-impedance)
AUTO-SHUTDOWN BLOCK DIAGRAM
ECCPAS<2:0>
PSSAC<0>
P1A_DRV
111
1
0
110
PSSAC<1>
101
100
INT
P1A
TRISx
011
From Comparator C2
010
PSSBD<0>
From Comparator C1
001
P1B_DRV
000
1
0
PRSEN
PSSBD<1>
From Data Bus
Write to ECCPASE
R
S
D
Q
P1B
TRISx
ECCPASE
PSSAC<0>
P1C_DRV
1
0
PSSAC<1>
P1C
TRISx
PSSBD<0>
P1D_DRV
1
0
PSSBD<1>
TRISx
© 2009 Microchip Technology Inc.
P1D
DS41291F-page 141
PIC16F882/883/884/886/887
REGISTER 11-3:
ECCPAS: ENHANCED CAPTURE/COMPARE/PWM AUTO-SHUTDOWN
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-0
ECCPASE
ECCPAS2
ECCPAS1
ECCPAS0
PSSAC1
PSSAC0
PSSBD1
PSSBD0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ECCPASE: ECCP Auto-Shutdown Event Status bit
1 = A shutdown event has occurred; ECCP outputs are in shutdown state
0 = ECCP outputs are operating
bit 6-4
ECCPAS<2:0>: ECCP Auto-shutdown Source Select bits
000 = Auto-Shutdown is disabled
001 = Comparator C1 output high
010 = Comparator C2 output high(1)
011 = Either Comparators output is high
100 = VIL on INT pin
101 = VIL on INT pin or Comparator C1 output high
110 = VIL on INT pin or Comparator C2 output high
111 =VIL on INT pin or either Comparators output is high
bit 3-2
PSSACn: Pins P1A and P1C Shutdown State Control bits
00 = Drive pins P1A and P1C to ‘0’
01 = Drive pins P1A and P1C to ‘1’
1x = Pins P1A and P1C tri-state
bit 1-0
PSSBDn: Pins P1B and P1D Shutdown State Control bits
00 = Drive pins P1B and P1D to ‘0’
01 = Drive pins P1B and P1D to ‘1’
1x = Pins P1B and P1D tri-state
Note 1:
If C2SYNC is enabled, the shutdown will be delayed by Timer1.
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 ECCPASE bit is disabled
while an auto-shutdown condition
persists.
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.
DS41291F-page 142
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 11-15:
PWM AUTO-SHUTDOWN WITH FIRMWARE RESTART (PRSEN = 0)
Shutdown Event
ECCPASE bit
PWM Activity
PWM Period
ECCPASE
Cleared by
Shutdown
Shutdown Firmware PWM
Event Occurs Event Clears
Resumes
Start of
PWM Period
11.6.5
AUTO-RESTART MODE
The Enhanced PWM can be configured to automatically restart the PWM signal once the auto-shutdown
condition has been removed. Auto-restart is enabled by
setting the PRSEN bit in the PWM1CON register.
If auto-restart is enabled, the ECCPASE bit will remain
set as long as the auto-shutdown condition is active.
When the auto-shutdown condition is removed, the
ECCPASE bit will be cleared via hardware and normal
operation will resume.
FIGURE 11-16:
PWM AUTO-SHUTDOWN WITH AUTO-RESTART ENABLED (PRSEN = 1)
Shutdown Event
ECCPASE bit
PWM Activity
PWM Period
Start of
PWM Period
© 2009 Microchip Technology Inc.
Shutdown
Shutdown
Event Occurs Event Clears
PWM
Resumes
DS41291F-page 143
PIC16F882/883/884/886/887
11.6.6
PROGRAMMABLE DEAD-BAND
DELAY MODE
FIGURE 11-17:
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
P1A(2)
td
td
P1B(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 11-17 for illustration. The
lower seven bits of the associated PWM1CON register
(Register 11-4) sets the delay period in terms of
microcontroller instruction cycles (TCY or 4 TOSC).
FIGURE 11-18:
EXAMPLE OF HALFBRIDGE PWM OUTPUT
At this time, the TMR2 register is equal to the
PR2 register.
Output signals are shown as active-high.
EXAMPLE OF HALF-BRIDGE APPLICATIONS
V+
Standard Half-Bridge Circuit (“Push-Pull”)
FET
Driver
+
V
-
P1A
Load
FET
Driver
+
V
-
P1B
V-
DS41291F-page 144
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 11-4:
PWM1CON: ENHANCED PWM 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-0
PRSEN
PDC6
PDC5
PDC4
PDC3
PDC2
PDC1
PDC0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
PRSEN: PWM Restart Enable bit
1 = Upon auto-shutdown, the ECCPASE bit clears automatically once the shutdown event goes
away; the PWM restarts automatically
0 = Upon auto-shutdown, ECCPASE must be cleared in software to restart the PWM
bit 6-0
PDC<6:0>: PWM Delay Count bits
PDCn = 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.
© 2009 Microchip Technology Inc.
DS41291F-page 145
PIC16F882/883/884/886/887
11.6.7
PULSE STEERING MODE
In Single Output mode, pulse steering allows any of the
PWM pins to be the modulated signal. Additionally, the
same PWM signal can be simultaneously available on
multiple pins.
Once the Single Output mode is selected
(CCP1M<3:2> = 11 and P1M<1:0> = 00 of the
CCP1CON register), the user firmware can bring out
the same PWM signal to one, two, three or four output
pins by setting the appropriate STR<D:A> bits of the
PSTRCON register, as shown in Table 11-5.
REGISTER 11-5:
Note:
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.
While the PWM Steering mode is active, CCP1M<1:0>
bits of the CCP1CON register select the PWM output
polarity for the P1<D:A> pins.
The PWM auto-shutdown operation also applies to
PWM Steering mode as described in Section 11.6.4
“Enhanced PWM Auto-shutdown mode”. An autoshutdown event will only affect pins that have PWM
outputs enabled.
PSTRCON: PULSE STEERING CONTROL REGISTER(1)
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
—
—
—
STRSYNC
STRD
STRC
STRB
STRA
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
STRSYNC: 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
STRD: Steering Enable bit D
1 = P1D pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = P1D pin is assigned to port pin
bit 2
STRC: Steering Enable bit C
1 = P1C pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = P1C pin is assigned to port pin
bit 1
STRB: Steering Enable bit B
1 = P1B pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = P1B pin is assigned to port pin
bit 0
STRA: Steering Enable bit A
1 = P1A pin has the PWM waveform with polarity control from CCPxM<1:0>
0 = P1A pin is assigned to port pin
Note 1:
The PWM Steering mode is available only when the CCP1CON register bits CCP1M<3:2> = 11 and
P1M<1:0> = 00.
DS41291F-page 146
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 11-19:
SIMPLIFIED STEERING
BLOCK DIAGRAM
STRA
P1A Signal
CCP1M1
1
PORT Data
0
P1A pin
STRB
CCP1M0
1
PORT Data
0
CCP1M1
1
PORT Data
0
P1C pin
TRIS
STRD
PORT Data
P1B pin
TRIS
STRC
CCP1M0
TRIS
P1D pin
1
0
TRIS
Note 1:
Port outputs are configured as shown when
the CCP1CON register bits P1M<1:0> = 00
and CCP1M<3:2> = 11.
2:
Single PWM output requires setting at least
one of the STRx bits.
© 2009 Microchip Technology Inc.
DS41291F-page 147
PIC16F882/883/884/886/887
11.6.7.1
Steering Synchronization
The STRSYNC bit of the PSTRCON register gives the
user two selections of when the steering event will
happen. When the STRSYNC bit is ‘0’, the steering
event will happen at the end of the instruction that
writes to the PSTRCON register. In this case, the
output signal at the P1<D:A> 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.
Figures 11-20 and 11-21 illustrate the timing diagrams
of the PWM steering depending on the STRSYNC
setting.
When the STRSYNC 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.
FIGURE 11-20:
EXAMPLE OF STEERING EVENT AT END OF INSTRUCTION (STRSYNC = 0)
PWM Period
PWM
STRn
P1<D:A>
PORT Data
PORT Data
P1n = PWM
FIGURE 11-21:
EXAMPLE OF STEERING EVENT AT BEGINNING OF INSTRUCTION
(STRSYNC = 1)
PWM
STRn
P1<D:A>
PORT Data
PORT Data
P1n = PWM
DS41291F-page 148
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 11-6:
Name
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE AND TIMER1
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
CCP1CON
P1M1
P1M0
DC1B1
DC1B0
CCP1M3
CCP2CON
—
—
DC2B1
DC2B0
CCP2M3
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
CCP1M2
CCP1M1
CCP1M0
0000 0000
0000 0000
CCP2M2
CCP2M1
CCP2M0
--00 0000
--00 0000
Bit 2
CCPR1L
Capture/Compare/PWM Register 1 Low Byte (LSB)
xxxx xxxx
xxxx xxxx
CCPR1H
Capture/Compare/PWM Register 1 High Byte (MSB)
xxxx xxxx
xxxx xxxx
CCPR2L
Capture/Compare/PWM Register 2 Low Byte (LSB)
xxxx xxxx
xxxx xxxx
CCPR2H
Capture/Compare/PWM Register 2 High Byte (MSB)
xxxx xxxx
xxxx xxxx
CM2CON1
MC1OUT
MC2OUT
C1RSEL
C2RSEL
—
—
T1GSS
C2SYNC
0000 --10
0000 --10
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
PIE2
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
0000 00-0
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
PIR2
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
0000 00-0
0000 00-0
T1GINV
TMR1GE
T1CKPS1
T1CKPS0
T1OSCEN
T1SYNC
TMR1CS
TMR1ON
INTCON
T1CON
0000 0000
0000 0000
TMR1L
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
xxxx xxxx
TMR1H
Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
xxxx xxxx
xxxx xxxx
1111 1111
1111 1111
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
Legend: – = Unimplemented locations, read as ‘0’, u = unchanged, x = unknown. Shaded cells are not used by the Capture and
Compare.
TABLE 11-7:
Name
REGISTERS ASSOCIATED WITH PWM AND TIMER2
Bit 4
Bit 0
Value on
POR, BOR
Value on
all other
Resets
CCP1M2
CCP1M1
CCP1M0
0000 0000
0000 0000
CCP2M2
CCP2M1
CCP2M0
--00 0000
--00 0000
PSSAC0
PSSBD1
PSSBD0
0000 0000
0000 0000
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
STRD
STRC
STRB
STRA
Bit 6
CCP1CON
P1M1
P1M0
DC1B1
DC1B0
CCP1M3
CCP2CON
—
—
DC2B1
DC2B0
CCP2M3
ECCPAS
ECCPASE
ECCPAS2
ECCPAS1
ECCPAS0
PSSAC1
INTCON
GIE
PEIE
T0IE
INTE
—
STRSYNC
PR2
Bit 5
Bit 1
Bit 7
Bit 3
Bit 2
Timer2 Period Register
1111 1111
1111 1111
---0 0001
---0 0001
PSTRCON
—
PWM1CON
PRSEN
PDC6
PDC5
PDC4
PDC3
PDC2
PDC1
PDC0
0000 0000
0000 0000
—
TOUTPS3
TOUTPS2
TOUTPS1
TOUTPS0
TMR2ON
T2CKPS1
T2CKPS0
-000 0000
-000 0000
0000 0000
0000 0000
T2CON
TMR2
—
Timer2 Module Register
TRISB
TRISB7
TRISB6
TRISB5
TRISB4
TRISB3
TRISB2
TRISB1
TRISB0
1111 1111
1111 1111
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
TRISD
TRISD7
TRISD6
TRISD5
TRISD4
TRISD3
TRISD2
TRISD1
TRISD0
1111 1111
1111 1111
Legend: – = Unimplemented locations, read as ‘0’, u = unchanged, x = unknown. Shaded cells are not used by the PWM.
© 2009 Microchip Technology Inc.
DS41291F-page 149
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 150
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.0
ENHANCED UNIVERSAL
SYNCHRONOUS
ASYNCHRONOUS RECEIVER
TRANSMITTER (EUSART)
The EUSART module includes the following capabilities:
•
•
•
•
•
•
•
•
•
•
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 polarity in synchronous
modes
• Sleep operation
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 12-1:
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 12-1 and Figure 12-2.
EUSART TRANSMIT BLOCK DIAGRAM
Data Bus
TXIE
Interrupt
TXIF
TXREG Register
8
MSb
TX/CK pin
LSb
(8)
• • •
0
Pin Buffer
and Control
TRMT
SPEN
Transmit Shift Register (TSR)
TXEN
Baud Rate Generator
FOSC
TX9
n
BRG16
+1
SPBRGH
÷n
SPBRG
Multiplier
x4
x16 x64
SYNC
1 X 0 0
0
BRGH
X 1 1 0
0
BRG16
X 1 0 1
0
© 2009 Microchip Technology Inc.
TX9D
DS41291F-page 151
PIC16F882/883/884/886/887
FIGURE 12-2:
EUSART RECEIVE BLOCK DIAGRAM
SPEN
CREN
RX/DT pin
Baud Rate Generator
Data
Recovery
FOSC
BRG16
SPBRGH
SPBRG
Multiplier
x4
x16 x64
SYNC
1 X 0 0
0
BRGH
X 1 1 0
0
BRG16
X 1 0 1
0
Stop
RCIDL
RSR Register
MSb
Pin Buffer
and Control
+1
OERR
(8)
•••
7
1
LSb
0 START
RX9
÷n
n
FERR
RX9D
RCREG Register
FIFO
8
Data Bus
RCIF
RCIE
Interrupt
The operation of the EUSART module is controlled
through three registers:
• Transmit Status and Control (TXSTA)
• Receive Status and Control (RCSTA)
• Baud Rate Control (BAUDCTL)
These registers are detailed in Register 12-1,
Register 12-2 and Register 12-3, respectively.
DS41291F-page 152
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.1
EUSART Asynchronous Mode
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 12-5
for examples of baud rate configurations.
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.
12.1.1
EUSART ASYNCHRONOUS
TRANSMITTER
The EUSART transmitter block diagram is shown in
Figure 12-1. 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 TXREG register.
12.1.1.1
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 TXSTA register enables the
transmitter circuitry of the EUSART. Clearing the SYNC
bit of the TXSTA register configures the EUSART for
asynchronous operation. Setting the SPEN bit of the
RCSTA register enables the EUSART and automatically
configures the TX/CK I/O pin as an output. If the TX/CK
pin is shared with an analog peripheral the analog I/O
function must be disabled by clearing the corresponding
ANSEL bit.
© 2009 Microchip Technology Inc.
Note 1: When the SPEN bit is set the RX/DT I/O pin
is automatically configured as an input,
regardless of the state of the corresponding
TRIS bit and whether or not the EUSART
receiver is enabled. The RX/DT pin data
can be read via a normal PORT read but
PORT latch data output is precluded.
2: The TXIF transmitter interrupt flag is set
when the TXEN enable bit is set.
12.1.1.2
Transmitting Data
A transmission is initiated by writing a character to the
TXREG register. If this is the first character, or the
previous character has been completely flushed from
the TSR, the data in the TXREG 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 TXREG until the Stop bit of the
previous character has been transmitted. The pending
character in the TXREG 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
TXREG.
12.1.1.3
Transmit Interrupt Flag
The TXIF interrupt flag bit of the PIR1 register is set
whenever the EUSART transmitter is enabled and no
character is being held for transmission in the TXREG.
In other words, the TXIF bit is only clear when the TSR
is busy with a character and a new character has been
queued for transmission in the TXREG. The TXIF flag bit
is not cleared immediately upon writing TXREG. TXIF
becomes valid in the second instruction cycle following
the write execution. Polling TXIF immediately following
the TXREG write will return invalid results. The TXIF bit
is read-only, it cannot be set or cleared by software.
The TXIF interrupt can be enabled by setting the TXIE
interrupt enable bit of the PIE1 register. However, the
TXIF flag bit will be set whenever the TXREG is empty,
regardless of the state of TXIE enable bit.
To use interrupts when transmitting data, set the TXIE
bit only when there is more data to send. Clear the
TXIE interrupt enable bit upon writing the last character
of the transmission to the TXREG.
DS41291F-page 153
PIC16F882/883/884/886/887
12.1.1.4
TSR Status
12.1.1.6
The TRMT bit of the TXSTA 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 TXREG. 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 has to
poll this bit to determine the TSR status.
Note:
12.1.1.5
1.
2.
3.
The TSR register is not mapped in data
memory, so it is not available to the user.
4.
Transmitting 9-Bit Characters
The EUSART supports 9-bit character transmissions.
When the TX9 bit of the TXSTA register is set the
EUSART will shift 9 bits out for each character transmitted. The TX9D bit of the TXSTA 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 TXREG. All nine bits
of data will be transferred to the TSR shift register
immediately after the TXREG is written.
5.
6.
7.
Asynchronous Transmission Set-up:
Initialize the SPBRGH, SPBRG register pair and
the BRGH and BRG16 bits to achieve the desired
baud rate (see Section 12.3 “EUSART Baud
Rate Generator (BRG)”).
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.
Enable the transmission by setting the TXEN
control bit. This will cause the TXIF interrupt bit
to be set.
If interrupts are desired, set the TXIE interrupt
enable bit of the PIE1 register. An interrupt will
occur immediately provided that the GIE and
PEIE 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 TXREG register. This
will start the transmission.
A special 9-bit Address mode is available for use with
multiple receivers. See Section 12.1.2.7 “Address
Detection” for more information on the Address mode.
FIGURE 12-3:
ASYNCHRONOUS TRANSMISSION
Write to TXREG
BRG Output
(Shift Clock)
Word 1
TX/CK
pin
Start bit
FIGURE 12-4:
bit 1
bit 7/8
Stop bit
Word 1
TXIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
bit 0
1 TCY
Word 1
Transmit Shift Reg
ASYNCHRONOUS TRANSMISSION (BACK TO BACK)
Write to TXREG
BRG Output
(Shift Clock)
Word 1
TX/CK
pin
TXIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Note:
Word 2
Start bit
bit 0
1 TCY
bit 1
Word 1
bit 7/8
Stop bit
Start bit
bit 0
Word 2
1 TCY
Word 1
Transmit Shift Reg.
Word 2
Transmit Shift Reg.
This timing diagram shows two consecutive transmissions.
DS41291F-page 154
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 12-1:
Name
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Bit 7
BAUDCTL ABDOVF
INTCON
PIE1
PIR1
RCREG
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
EUSART Receive Data Register
0000 0000
0000 0000
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
0000 0000
0000 0000
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
0000 0010
TXREG
TXSTA
Legend:
EUSART Transmit Data Register
CSRC
TX9
TXEN
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Asynchronous Transmission.
© 2009 Microchip Technology Inc.
DS41291F-page 155
PIC16F882/883/884/886/887
12.1.2
EUSART ASYNCHRONOUS
RECEIVER
The Asynchronous mode is typically used in RS-232
systems. The receiver block diagram is shown in
Figure 12-2. The data is received on the RX/DT 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-InFirst-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 RCREG register.
12.1.2.1
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 RCSTA register enables the
receiver circuitry of the EUSART. Clearing the SYNC bit
of the TXSTA register configures the EUSART for asynchronous operation. Setting the SPEN bit of the RCSTA
register enables the EUSART and automatically configures the RX/DT I/O pin as an input. If the RX/DT pin is
shared with an analog peripheral the analog I/O function
must be disabled by clearing the corresponding ANSEL
bit.
Note:
When the SPEN bit is set the TX/CK I/O
pin is automatically configured as an
output, regardless of the state of the
corresponding TRIS bit and whether or not
the EUSART transmitter is enabled. The
PORT latch is disconnected from the
output driver so it is not possible to use the
TX/CK pin as a general purpose output.
12.1.2.2
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 12.1.2.4 “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 RCIF interrupt
flag bit of the PIR1 register is set. The top character in
the FIFO is transferred out of the FIFO by reading the
RCREG register.
Note:
12.1.2.3
If the receive FIFO is overrun, no additional
characters will be received until the overrun
condition is cleared. See Section 12.1.2.5
“Receive Overrun Error” for more
information on overrun errors.
Receive Interrupts
The RCIF interrupt flag bit of the PIR1 register is set
whenever the EUSART receiver is enabled and there is
an unread character in the receive FIFO. The RCIF
interrupt flag bit is read-only, it cannot be set or cleared
by software.
RCIF interrupts are enabled by setting all of the
following bits:
• RCIE interrupt enable bit of the PIE1 register
• PEIE peripheral interrupt enable bit of the INTCON register
• GIE global interrupt enable bit of the INTCON
register
The RCIF interrupt flag bit will be set when there is an
unread character in the FIFO, regardless of the state of
interrupt enable bits.
DS41291F-page 156
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.1.2.4
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 RCSTA 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.
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.
The FERR bit can be forced clear by clearing the SPEN
bit of the RCSTA register which resets the EUSART.
Clearing the CREN bit of the RCSTA register does not
affect the FERR bit. A framing error by itself does not
generate an interrupt.
Note:
12.1.2.5
12.1.2.7
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 RCSTA
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 RCIF 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.
If all receive characters in the receive
FIFO have framing errors, repeated reads
of the RCREG 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 RCSTA 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 RCSTA register or by
resetting the EUSART by clearing the SPEN bit of the
RCSTA register.
12.1.2.6
Receiving 9-bit Characters
The EUSART supports 9-bit character reception. When
the RX9 bit of the RCSTA register is set the EUSART
will shift 9 bits into the RSR for each character
received. The RX9D bit of the RCSTA 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 RCREG.
© 2009 Microchip Technology Inc.
DS41291F-page 157
PIC16F882/883/884/886/887
12.1.2.8
1.
2.
3.
4.
5.
6.
7.
8.
9.
Asynchronous Reception Set-up:
12.1.2.9
Initialize the SPBRGH, SPBRG register pair and
the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 12.3 “EUSART
Baud Rate Generator (BRG)”).
Enable the serial port by setting the SPEN bit.
The SYNC bit must be clear for asynchronous
operation.
If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
If 9-bit reception is desired, set the RX9 bit.
Enable reception by setting the CREN bit.
The RCIF 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 RCIE interrupt enable bit was also set.
Read the RCSTA register to get the error flags
and, if 9-bit data reception is enabled, the ninth
data bit.
Get the received 8 Least Significant data bits
from the receive buffer by reading the RCREG
register.
If an overrun occurred, clear the OERR flag by
clearing the CREN receiver enable bit.
FIGURE 12-5:
Rcv Shift
Reg
Rcv Buffer Reg
RCIDL
This mode would typically be used in RS-485 systems.
To set up an Asynchronous Reception with Address
Detect Enable:
1.
Initialize the SPBRGH, SPBRG register pair and
the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 12.3 “EUSART
Baud Rate Generator (BRG)”).
2. Enable the serial port by setting the SPEN bit.
The SYNC bit must be clear for asynchronous
operation.
3. If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
4. Enable 9-bit reception by setting the RX9 bit.
5. Enable address detection by setting the ADDEN
bit.
6. Enable reception by setting the CREN bit.
7. The RCIF 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 RCIE interrupt enable bit
was also set.
8. Read the RCSTA register to get the error flags.
The ninth data bit will always be set.
9. Get the received 8 Least Significant data bits
from the receive buffer by reading the RCREG
register. Software determines if this is the
device’s address.
10. If an overrun occurred, clear the OERR flag by
clearing the CREN receiver enable bit.
11. If the device has been addressed, clear the
ADDEN bit to allow all received data into the
receive buffer and generate interrupts.
ASYNCHRONOUS RECEPTION
Start
bit
bit 0
RX/DT pin
9-bit Address Detection Mode Set-up
bit 1
bit 7/8 Stop
bit
Start
bit
Word 1
RCREG
bit 0
bit 7/8 Stop
bit
Start
bit
bit 7/8 Stop
bit
Word 2
RCREG
Read Rcv
Buffer Reg
RCREG
RCIF
(Interrupt Flag)
OERR bit
CREN
Note:
This timing diagram shows three words appearing on the RX input. The RCREG (receive buffer) is read after the third word,
causing the OERR (overrun) bit to be set.
DS41291F-page 158
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 12-2:
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Name
Bit 7
Bit 6
BAUDCTL
ABDOVF
GIE
INTCON
PIE1
PIR1
RCREG
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
0000 0000
0000 0000
Bit 5
Bit 4
Bit 3
RCIDL
—
SCKP
PEIE
T0IE
INTE
—
ADIE
RCIE
—
ADIF
RCIF
EUSART Receive Data Register
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
TXREG
TXSTA
Legend:
EUSART Transmit Data Register
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0000
0000 0000
0000 0010
0000 0010
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Asynchronous Reception.
© 2009 Microchip Technology Inc.
DS41291F-page 159
PIC16F882/883/884/886/887
12.2
Clock Accuracy with
Asynchronous Operation
The factory calibrates the Internal Oscillator block output (INTOSC). However, the INTOSC 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 12-1:
The first (preferred) method uses the OSCTUNE
register to adjust the INTOSC output. Adjusting the
value in the OSCTUNE register allows for fine resolution
changes to the system clock source. See Section 4.5
“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 12.3.1 “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.
TXSTA: 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.
DS41291F-page 160
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 12-2:
RCSTA: RECEIVE STATUS AND CONTROL REGISTER(1)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R-0
R-0
R-x
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
SPEN: Serial Port Enable bit
1 = Serial port enabled (configures RX/DT and TX/CK pins as serial port pins)
0 = Serial port disabled (held in Reset)
bit 6
RX9: 9-bit Receive Enable bit
1 = Selects 9-bit reception
0 = Selects 8-bit reception
bit 5
SREN: Single Receive Enable bit
Asynchronous mode:
Don’t care
Synchronous mode – Master:
1 = Enables single receive
0 = Disables single receive
This bit is cleared after reception is complete.
Synchronous mode – Slave
Don’t care
bit 4
CREN: Continuous Receive Enable bit
Asynchronous mode:
1 = Enables receiver
0 = Disables receiver
Synchronous mode:
1 = Enables continuous receive until enable bit CREN is cleared (CREN overrides SREN)
0 = Disables continuous receive
bit 3
ADDEN: Address Detect Enable bit
Asynchronous mode 9-bit (RX9 = 1):
1 = Enables address detection, 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 RCREG 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.
© 2009 Microchip Technology Inc.
DS41291F-page 161
PIC16F882/883/884/886/887
REGISTER 12-3:
BAUDCTL: BAUD RATE CONTROL REGISTER
R-0
R-1
U-0
R/W-0
R/W-0
U-0
R/W-0
R/W-0
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ABDOVF: Auto-Baud 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 received and the receiver is receiving
Synchronous mode:
Don’t care
bit 5
Unimplemented: Read as ‘0’
bit 4
SCKP: Synchronous Clock Polarity Select bit
Asynchronous mode:
1 = Transmit inverted data to the RB7/TX/CK pin
0 = Transmit non-inverted data to the RB7/TX/CK pin
Synchronous mode:
1 = Data is clocked on rising edge of the clock
0 = Data is clocked on falling edge of the clock
bit 3
BRG16: 16-bit Baud Rate Generator bit
1 = 16-bit Baud Rate Generator is used
0 = 8-bit Baud Rate Generator is used
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 byte RCIF will be set. WUE will
automatically clear after RCIF is set.
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
DS41291F-page 162
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.3
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 BAUDCTL register selects 16-bit
mode.
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 12-1:
For a device with FOSC of 16 MHz, desired baud rate
of 9600, Asynchronous mode, 8-bit BRG:
The SPBRGH, SPBRG 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 TXSTA
register and the BRG16 bit of the BAUDCTL register. In
Synchronous mode, the BRGH bit is ignored.
F OS C
Desired Baud Rate = --------------------------------------------------------------------64 ( [SPBRGH:SPBRG] + 1 )
Solving for SPBRGH:SPBRG:
FOSC
--------------------------------------------Desired Baud Rate
X = --------------------------------------------- – 1
64
Table 12-3 contains the formulas for determining the
baud rate. Example 12-1 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 12-3. 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 )
= 9615
Writing a new value to the SPBRGH, SPBRG 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 12-3:
CALCULATING BAUD
RATE ERROR
Calc. Baud Rate – Desired Baud Rate
Error = -------------------------------------------------------------------------------------------Desired Baud Rate
( 9615 – 9600 )
= ---------------------------------- = 0.16%
9600
BAUD RATE FORMULAS
Configuration Bits
BRG/EUSART Mode
Baud Rate Formula
0
8-bit/Asynchronous
FOSC/[64 (n+1)]
0
1
8-bit/Asynchronous
0
1
0
16-bit/Asynchronous
0
1
1
16-bit/Asynchronous
1
0
x
8-bit/Synchronous
1
x
16-bit/Synchronous
SYNC
BRG16
BRGH
0
0
0
FOSC/[16 (n+1)]
1
Legend:
FOSC/[4 (n+1)]
x = Don’t care, n = value of SPBRGH, SPBRG register pair
TABLE 12-4:
REGISTERS ASSOCIATED WITH THE BAUD RATE GENERATOR
Name
Bit 7
Bit 6
BAUDCTL
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TXSTA
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
0000 0010
Legend:
x = unknown, - = unimplemented read as ‘0’. Shaded cells are not used for the Baud Rate Generator.
© 2009 Microchip Technology Inc.
DS41291F-page 163
PIC16F882/883/884/886/887
TABLE 12-5:
BAUD RATES FOR ASYNCHRONOUS MODES
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
FOSC = 20.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 18.432 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 11.0592 MHz
Actual
Rate
%
Error
FOSC = 8.000 MHz
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
—
—
—
—
—
—
—
—
—
—
—
—
1200
1221
1.73
255
1200
0.00
239
1200
0.00
143
1202
0.16
103
2400
2404
0.16
129
2400
0.00
119
2400
0.00
71
2404
0.16
51
9600
9470
-1.36
32
9600
0.00
29
9600
0.00
17
9615
0.16
12
10417
10417
0.00
29
10286
-1.26
27
10165
-2.42
16
10417
0.00
11
19.2k
19.53k
1.73
15
19.20k
0.00
14
19.20k
0.00
8
—
—
—
57.6k
—
—
—
57.60k
0.00
7
57.60k
0.00
2
—
—
—
115.2k
—
—
—
—
—
—
—
—
—
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 0
BAUD
RATE
FOSC = 4.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 3.6864 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 2.000 MHz
Actual
Rate
FOSC = 1.000 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
300
0.16
207
300
0.00
191
300
0.16
103
300
0.16
51
1200
1202
0.16
51
1200
0.00
47
1202
0.16
25
1202
0.16
12
2400
2404
0.16
25
2400
0.00
23
2404
0.16
12
—
—
—
9600
—
—
—
9600
0.00
5
—
—
—
—
—
—
10417
10417
0.00
5
—
—
—
10417
0.00
2
—
—
—
19.2k
—
—
—
19.20k
0.00
2
—
—
—
—
—
—
57.6k
—
—
—
57.60k
0.00
0
—
—
—
—
—
—
115.2k
—
—
—
—
—
—
—
—
—
—
—
—
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
FOSC = 20.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 18.432 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 11.0592 MHz
Actual
Rate
%
Error
FOSC = 8.000 MHz
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
—
—
—
—
—
—
—
—
—
—
—
—
1200
—
—
—
—
—
—
—
—
—
—
—
—
2400
—
—
—
—
—
—
—
—
—
2404
0.16
207
9600
9615
0.16
129
9600
0.00
119
9600
0.00
71
9615
0.16
51
10417
10417
0.00
119
10378
-0.37
110
10473
0.53
65
10417
0.00
47
19.2k
19.23k
0.16
64
19.20k
0.00
59
19.20k
0.00
35
19231
0.16
25
57.6k
56.82k
-1.36
21
57.60k
0.00
19
57.60k
0.00
11
55556
-3.55
8
115.2k
113.64k
-1.36
10
115.2k
0.00
9
115.2k
0.00
5
—
—
—
DS41291F-page 164
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 12-5:
BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
SYNC = 0, BRGH = 1, BRG16 = 0
BAUD
RATE
FOSC = 4.000 MHz
FOSC = 3.6864 MHz
FOSC = 2.000 MHz
FOSC = 1.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
1200
—
1202
—
0.16
—
207
—
1200
—
0.00
—
191
—
1202
—
0.16
—
103
300
1202
0.16
0.16
207
51
2400
2404
0.16
103
2400
0.00
95
2404
0.16
51
2404
0.16
25
—
Actual
Rate
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
9600
9615
0.16
25
9600
0.00
23
9615
0.16
12
—
—
10417
10417
0.00
23
10473
0.53
21
10417
0.00
11
10417
0.00
5
19.2k
19.23k
0.16
12
19.2k
0.00
11
—
—
—
—
—
—
57.6k
—
—
—
57.60k
0.00
3
—
—
—
—
—
—
115.2k
—
—
—
115.2k
0.00
1
—
—
—
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
FOSC = 20.000 MHz
Actual
Rate
FOSC = 18.432 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
FOSC = 11.0592 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
FOSC = 8.000 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
1666
300
300.0
-0.01
4166
300.0
0.00
3839
300.0
0.00
2303
299.9
-0.02
1200
1200
-0.03
1041
1200
0.00
959
1200
0.00
575
1199
-0.08
416
2400
2399
-0.03
520
2400
0.00
479
2400
0.00
287
2404
0.16
207
51
9600
9615
0.16
129
9600
0.00
119
9600
0.00
71
9615
0.16
10417
10417
0.00
119
10378
-0.37
110
10473
0.53
65
10417
0.00
47
19.2k
19.23k
0.16
64
19.20k
0.00
59
19.20k
0.00
35
19.23k
0.16
25
57.6k
56.818
-1.36
21
57.60k
0.00
19
57.60k
0.00
11
55556
-3.55
8
115.2k
113.636
-1.36
10
115.2k
0.00
9
115.2k
0.00
5
—
—
—
SYNC = 0, BRGH = 0, BRG16 = 1
BAUD
RATE
FOSC = 4.000 MHz
Actual
Rate
%
Error
FOSC = 3.6864 MHz
SPBRG
value
(decimal)
Actual
Rate
%
Error
FOSC = 2.000 MHz
SPBRG
value
(decimal)
Actual
Rate
%
Error
FOSC = 1.000 MHz
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
300.1
0.04
832
300.0
0.00
767
299.8
-0.108
416
300.5
0.16
207
1200
1202
0.16
207
1200
0.00
191
1202
0.16
103
1202
0.16
51
2400
2404
0.16
103
2400
0.00
95
2404
0.16
51
2404
0.16
25
9600
9615
0.16
25
9600
0.00
23
9615
0.16
12
—
—
—
10417
10417
0.00
23
10473
0.53
21
10417
0.00
11
10417
0.00
5
19.2k
19.23k
0.16
12
19.20k
0.00
11
—
—
—
—
—
—
57.6k
—
—
—
57.60k
0.00
3
—
—
—
—
—
—
115.2k
—
—
—
115.2k
0.00
1
—
—
—
—
—
—
© 2009 Microchip Technology Inc.
DS41291F-page 165
PIC16F882/883/884/886/887
TABLE 12-5:
BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED)
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
FOSC = 20.000 MHz
FOSC = 18.432 MHz
FOSC = 11.0592 MHz
FOSC = 8.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
300
1200
300.0
1200
0.00
-0.01
16665
4166
300.0
1200
0.00
0.00
15359
3839
300.0
1200
0.00
0.00
9215
2303
300.0
1200
0.00
-0.02
6666
1666
2400
2400
0.02
2082
2400
0.00
1919
2400
0.00
1151
2401
0.04
832
9600
9597
-0.03
520
9600
0.00
479
9600
0.00
287
9615
0.16
207
10417
10417
0.00
479
10425
0.08
441
10433
0.16
264
10417
0
191
Actual
Rate
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
19.2k
19.23k
0.16
259
19.20k
0.00
239
19.20k
0.00
143
19.23k
0.16
103
57.6k
57.47k
-0.22
86
57.60k
0.00
79
57.60k
0.00
47
57.14k
-0.79
34
115.2k
116.3k
0.94
42
115.2k
0.00
39
115.2k
0.00
23
117.6k
2.12
16
SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1
BAUD
RATE
FOSC = 4.000 MHz
Actual
Rate
%
Error
SPBRG
value
(decimal)
FOSC = 3.6864 MHz
Actual
Rate
FOSC = 2.000 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
FOSC = 1.000 MHz
%
Error
SPBRG
value
(decimal)
Actual
Rate
%
Error
SPBRG
value
(decimal)
832
300
300.0
0.01
3332
300.0
0.00
3071
299.9
-0.02
1666
300.1
0.04
1200
1200
0.04
832
1200
0.00
767
1199
-0.08
416
1202
0.16
207
2400
2398
0.08
416
2400
0.00
383
2404
0.16
207
2404
0.16
103
9600
9615
0.16
103
9600
0.00
95
9615
0.16
51
9615
0.16
25
10417
10417
0.00
95
10473
0.53
87
10417
0.00
47
10417
0.00
23
19.2k
19.23k
0.16
51
19.20k
0.00
47
19.23k
0.16
25
19.23k
0.16
12
57.6k
58.82k
2.12
16
57.60k
0.00
15
55.56k
-3.55
8
—
—
—
115.2k
111.1k
-3.55
8
115.2k
0.00
7
—
—
—
—
—
—
DS41291F-page 166
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.3.1
AUTO-BAUD DETECT
The EUSART module supports automatic detection
and calibration of the baud rate.
and SPBRG 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.
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 12.3.2
“Auto-Wake-up
on
Break”).
In the Auto-Baud Detect (ABD) mode, the clock to the
BRG is reversed. Rather than the BRG clocking the
incoming RX signal, the RX signal is timing the BRG.
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 BAUDCTL register starts
the auto-baud calibration sequence (Figure 12-6).
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 SPBRG begins
counting up using the BRG counter clock as shown in
Table 12-6. The fifth rising edge will occur on the RX pin
at the end of the eighth bit period. At that time, an
accumulated value totaling the proper BRG period is
left in the SPBRGH, SPBRG register pair, the ABDEN
bit is automatically cleared and the RCIF interrupt flag
is set. The value in the RCREG needs to be read to
clear the RCIF interrupt. RCREG content should be
discarded. When calibrating for modes that do not use
the SPBRGH register the user can verify that the
SPBRG register did not overflow by checking for 00h in
the SPBRGH register.
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 SPBRGH:SPBRG register pair.
TABLE 12-6:
The BRG auto-baud clock is determined by the BRG16
and BRGH bits as shown in Table 12-6. During ABD,
both the SPBRGH and SPBRG registers are used as a
16-bit counter, independent of the BRG16 bit setting.
While calibrating the baud rate period, the SPBRGH
FIGURE 12-6:
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, SPBRG and
SPBRGH registers are both used as a 16-bit
counter, independent of BRG16 setting.
AUTOMATIC BAUD RATE CALIBRATION
XXXXh
BRG Value
BRG COUNTER CLOCK RATES
RX pin
0000h
001Ch
Start
Edge #1
bit 1
bit 0
Edge #2
bit 3
bit 2
Edge #3
bit 5
bit 4
Edge #4
bit 7
bit 6
Edge #5
Stop bit
BRG Clock
Auto Cleared
Set by User
ABDEN bit
RCIDL
RCIF bit
(Interrupt)
Read
RCREG
SPBRG
XXh
1Ch
SPBRGH
XXh
00h
Note 1:
The ABD sequence requires the EUSART module to be configured in Asynchronous mode
© 2009 Microchip Technology Inc.
DS41291F-page 167
PIC16F882/883/884/886/887
12.3.2
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 RX/DT line.
This feature is available only in Asynchronous mode.
The Auto-Wake-up feature is enabled by setting the
WUE bit of the BAUDCTL register. Once set, the normal
receive sequence on RX/DT is disabled, and the
EUSART remains in an Idle state, monitoring for a wakeup event independent of the CPU mode. A wake-up
event consists of a high-to-low transition on the RX/DT
line. (This coincides with the start of a Sync Break or a
wake-up signal character for the LIN protocol.)
The EUSART module generates an RCIF interrupt
coincident with the wake-up event. The interrupt is
generated synchronously to the Q clocks in normal CPU
operating modes (Figure 12-7), and asynchronously if
the device is in Sleep mode (Figure 12-8). The interrupt
condition is cleared by reading the RCREG register.
The WUE bit is automatically cleared by the low-to-high
transition on the RX 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.
12.3.2.1
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 RCIF bit. The WUE bit is cleared in
hardware by a rising edge on RX/DT. The interrupt
condition is then cleared in software by reading the
RCREG 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.
FIGURE 12-7:
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
RX/DT Line
RCIF
Note 1:
Cleared due to User Read of RCREG
The EUSART remains in Idle while the WUE bit is set.
DS41291F-page 168
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 12-8:
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
RX/DT Line
Note 1
RCIF
Sleep Command Executed
Note 1:
2:
12.3.3
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.
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 TXSTA register. The Break character transmission is then initiated by a write to the TXREG. The
value of data written to TXREG will be ignored and all
‘0’s will be transmitted.
The SENDB bit is automatically reset by hardware after
the corresponding Stop bit is sent. This allows the user
to preload the transmit FIFO with the next transmit byte
following the Break character (typically, the Sync
character in the LIN specification).
The TRMT bit of the TXSTA register indicates when the
transmit operation is active or Idle, just as it does during
normal transmission. See Figure 12-9 for the timing of
the Break character sequence.
12.3.3.1
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.
Cleared due to User Read of RCREG
Sleep Ends
12.3.4
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 RCSTA register and the Received data
as indicated by RCREG. The Baud Rate Generator is
assumed to have been initialized to the expected baud
rate.
A Break character has been received when;
• RCIF bit is set
• FERR bit is set
• RCREG = 00h
The second method uses the Auto-Wake-up feature
described in Section 12.3.2 “Auto-Wake-up on
Break”. By enabling this feature, the EUSART will
sample the next two transitions on RX/DT, cause an
RCIF interrupt, and receive the next data byte followed
by another interrupt.
Note that following a Break character, the user will
typically want to enable the Auto-Baud Detect feature.
For both methods, the user can set the ABDEN bit of
the BAUDCTL register before placing the EUSART in
Sleep mode.
Configure the EUSART for the desired mode.
Set the TXEN and SENDB bits to enable the
Break sequence.
Load the TXREG with a dummy character to
initiate transmission (the value is ignored).
Write ‘55h’ to TXREG to load the Sync character
into the transmit FIFO buffer.
After the Break has been sent, the SENDB bit is
reset by hardware and the Sync character is
then transmitted.
When the TXREG becomes empty, as indicated by the
TXIF, the next data byte can be written to TXREG.
© 2009 Microchip Technology Inc.
DS41291F-page 169
PIC16F882/883/884/886/887
FIGURE 12-9:
Write to TXREG
SEND BREAK CHARACTER SEQUENCE
Dummy Write
BRG Output
(Shift Clock)
TX (pin)
Start bit
bit 0
bit 1
bit 11
Stop bit
Break
TXIF bit
(Transmit
Interrupt Flag)
TRMT bit
(Transmit Shift
Empty Flag)
SENDB Sampled Here
Auto Cleared
SENDB
(send Break
control bit)
DS41291F-page 170
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.4
EUSART Synchronous Mode
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.
12.4.1
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
Setting the SYNC bit of the TXSTA register configures
the device for synchronous operation. Setting the CSRC
bit of the TXSTA register configures the device as a
master. Clearing the SREN and CREN bits of the RCSTA
register ensures that the device is in the Transmit mode,
otherwise the device will be configured to receive. Setting
the SPEN bit of the RCSTA register enables the
EUSART. If the RX/DT or TX/CK pins are shared with an
analog peripheral the analog I/O functions must be
disabled by clearing the corresponding ANSEL bits.
12.4.1.1
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 TX/CK line.
The TX/CK 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.
© 2009 Microchip Technology Inc.
12.4.1.2
Clock Polarity
A clock polarity option is provided for Microwire
compatibility. Clock polarity is selected with the SCKP
bit of the BAUDCTL register. Setting the SCKP bit sets
the clock Idle state as high. When the SCKP bit is set,
the data changes on the falling edge of each clock.
Clearing the SCKP bit sets the Idle state as low. When
the SCKP bit is cleared, the data changes on the rising
edge of each clock.
12.4.1.3
Synchronous Master Transmission
Data is transferred out of the device on the RX/DT pin.
The RX/DT and TX/CK 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
TXREG register. If the TSR still contains all or part of a
previous character the new character data is held in the
TXREG 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 TXREG is immediately transferred
to the TSR. The transmission of the character commences immediately following the transfer of the data
to the TSR from the TXREG.
Each data bit changes on the leading edge of the
master clock and remains valid until the subsequent
leading clock edge.
Note:
The TSR register is not mapped in data
memory, so it is not available to the user.
12.4.1.4
Synchronous Master Transmission
Set-up:
1.
2.
3.
4.
5.
6.
7.
8.
Initialize the SPBRGH, SPBRG register pair and
the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 12.3 “EUSART
Baud Rate Generator (BRG)”).
Enable the synchronous master serial port by
setting bits SYNC, SPEN, and CSRC.
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 TXIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
If 9-bit transmission is selected, the ninth bit
should be loaded in the TX9D bit.
Start transmission by loading data to the TXREG
register.
DS41291F-page 171
PIC16F882/883/884/886/887
FIGURE 12-10:
SYNCHRONOUS TRANSMISSION
RX/DT
pin
bit 0
bit 1
Word 1
bit 2
bit 7
bit 0
bit 1
Word 2
bit 7
TX/CK pin
(SCKP = 0)
TX/CK pin
(SCKP = 1)
Write to
TXREG Reg
Write Word 1
Write Word 2
TXIF bit
(Interrupt Flag)
TRMT bit
TXEN bit
‘1’
Note:
‘1’
Sync Master mode, SPBRG = 0, continuous transmission of two 8-bit words.
FIGURE 12-11:
SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RX/DT pin
bit 0
bit 2
bit 1
bit 6
bit 7
TX/CK pin
Write to
TXREG reg
TXIF bit
TRMT bit
TXEN bit
TABLE 12-7:
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Name
Bit 7
Bit 6
BAUDCTL
ABDOVF
GIE
PIE1
PIR1
INTCON
RCREG
RCSTA
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
0000 0000
0000 0000
RX9D
0000 000x
0000 000x
0000 0000
Bit 5
Bit 4
Bit 3
RCIDL
—
SCKP
PEIE
T0IE
INTE
—
ADIE
RCIE
—
ADIF
RCIF
EUSART Receive Data Register
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
0000 0000
0000 0000
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
0000 0010
TXREG
TXSTA
Legend:
EUSART Transmit Data Register
CSRC
TX9
TXEN
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Synchronous Master Transmission.
DS41291F-page 172
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.4.1.5
Synchronous Master Reception
Data is received at the RX/DT pin. The RX/DT pin
output driver is automatically disabled 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
RCSTA register) or the Continuous Receive Enable bit
(CREN of the RCSTA 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 RX/DT pin on the trailing edge of the
TX/CK clock pin and is shifted into the Receive Shift
Register (RSR). When a complete character is
received into the RSR, the RCIF 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 RCREG.
The RCIF bit remains set as long as there are un-read
characters in the receive FIFO.
12.4.1.6
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 TX/CK line. The TX/
CK pin output driver is automatically disabled 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.
12.4.1.7
Receive Overrun Error
set then the error condition is cleared by either clearing
the CREN bit of the RCSTA register or by clearing the
SPEN bit which resets the EUSART.
12.4.1.8
Receiving 9-bit Characters
The EUSART supports 9-bit character reception. When
the RX9 bit of the RCSTA register is set the EUSART
will shift 9-bits into the RSR for each character
received. The RX9D bit of the RCSTA 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 RCREG.
12.4.1.9
Synchronous Master Reception Setup:
1.
Initialize the SPBRGH, SPBRG register pair for
the appropriate baud rate. Set or clear the
BRGH and BRG16 bits, as required, to achieve
the desired baud rate.
2. Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC.
3. Ensure bits CREN and SREN are clear.
4. If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
5. If 9-bit reception is desired, set bit RX9.
6. Start reception by setting the SREN bit or for
continuous reception, set the CREN bit.
7. Interrupt flag bit RCIF will be set when reception
of a character is complete. An interrupt will be
generated if the enable bit RCIE was set.
8. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
9. Read the 8-bit received data by reading the
RCREG register.
10. If an overrun error occurs, clear the error by
either clearing the CREN bit of the RCSTA
register or by clearing the SPEN bit which resets
the EUSART.
The receive FIFO buffer can hold two characters. An
overrun error will be generated if a third character, in its
entirety, is received before RCREG is read to access
the FIFO. When this happens the OERR bit of the
RCSTA 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
RCREG. If the overrun occurred when the CREN bit is
© 2009 Microchip Technology Inc.
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FIGURE 12-12:
SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
RX/DT
pin
bit 0
bit 1
bit 2
bit 3
bit 4
bit 5
bit 6
bit 7
TX/CK pin
(SCKP = 0)
TX/CK pin
(SCKP = 1)
Write to
bit SREN
SREN bit
CREN bit ‘0’
‘0’
RCIF bit
(Interrupt)
Read
RXREG
Note:
Timing diagram demonstrates Sync Master mode with bit SREN = 1 and bit BRGH = 0.
TABLE 12-8:
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
BAUDCTL
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
INTCON
PIE1
PIR1
RCREG
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
EUSART Receive Data Register
FERR
OERR
0000 0000
RX9D
0000 000x
0000 000x
RCSTA
SPEN
RX9
SREN
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
0000 0000
0000 0000
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0010
0000 0010
TXREG
TXSTA
Legend:
CREN
ADDEN
0000 0000
EUSART Transmit Data Register
CSRC
TX9
TXEN
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Synchronous Master Reception.
DS41291F-page 174
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
12.4.2
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 TXSTA register configures the
device for synchronous operation. Clearing the CSRC bit
of the TXSTA register configures the device as a slave.
Clearing the SREN and CREN bits of the RCSTA register
ensures that the device is in the Transmit mode,
otherwise the device will be configured to receive. Setting
the SPEN bit of the RCSTA register enables the
EUSART. If the RX/DT or TX/CK pins are shared with an
analog peripheral the analog I/O functions must be
disabled by clearing the corresponding ANSEL bits.
12.4.2.1
If two words are written to the TXREG and then the
SLEEP instruction is executed, the following will occur:
5.
12.4.2.2
1.
2.
3.
EUSART Synchronous Slave
Transmit
The operation of the Synchronous Master and Slave
modes
are
identical
(see
Section 12.4.1.3
“Synchronous Master Transmission”), except in the
case of the Sleep mode.
4.
5.
6.
7.
TABLE 12-9:
Bit 7
Bit 6
BAUDCTL
ABDOVF
GIE
PIE1
PIR1
RCREG
Synchronous Slave Transmission
Set-up:
Set the SYNC and SPEN bits and clear the
CSRC bit.
Clear the CREN and SREN bits.
If interrupts are desired, set the TXIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
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 TXREG register.
REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Name
INTCON
The first character will immediately transfer to
the TSR register and transmit.
The second word will remain in TXREG register.
The TXIF bit will not be set.
After the first character has been shifted out of
TSR, the TXREG register will transfer the second
character to the TSR and the TXIF bit will now be
set.
If the PEIE and TXIE bits are set, the interrupt
will wake the device from Sleep and execute the
next instruction. If the GIE bit is also set, the
program will call the Interrupt Service Routine.
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
0000 0000
0000 0000
Bit 5
Bit 4
Bit 3
RCIDL
—
SCKP
PEIE
T0IE
INTE
—
ADIE
RCIE
—
ADIF
RCIF
EUSART Receive Data Register
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
0000 0000
0000 0000
0000 0010
0000 0010
TRISC
TXREG
TXSTA
Legend:
EUSART Transmit Data Register
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Synchronous Slave Transmission.
© 2009 Microchip Technology Inc.
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12.4.2.3
EUSART Synchronous Slave
Reception
12.4.2.4
The operation of the Synchronous Master and Slave
modes is identical (Section 12.4.1.5 “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
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 RCREG register. If the RCIE enable bit is set, the
interrupt generated will wake the device from Sleep
and execute the next instruction. If the GIE bit is also
set, the program will branch to the interrupt vector.
1.
2.
3.
4.
5.
6.
7.
8.
Synchronous Slave Reception Setup:
Set the SYNC and SPEN bits and clear the
CSRC bit.
If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
If 9-bit reception is desired, set the RX9 bit.
Set the CREN bit to enable reception.
The RCIF bit will be set when reception is
complete. An interrupt will be generated if the
RCIE bit was set.
If 9-bit mode is enabled, retrieve the Most
Significant bit from the RX9D bit of the RCSTA
register.
Retrieve the 8 Least Significant bits from the
receive FIFO by reading the RCREG register.
If an overrun error occurs, clear the error by
either clearing the CREN bit of the RCSTA
register or by clearing the SPEN bit which resets
the EUSART.
TABLE 12-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name
Bit 7
Bit 6
BAUDCTL
ABDOVF
GIE
PIE1
PIR1
INTCON
RCREG
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
BRG16
—
WUE
ABDEN
01-0 0-00
01-0 0-00
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
Bit 5
Bit 4
Bit 3
RCIDL
—
SCKP
PEIE
T0IE
INTE
—
ADIE
RCIE
—
ADIF
RCIF
EUSART Receive Data Register
0000 0000
0000 0000
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
0000 000x
0000 000x
SPBRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
0000 0000
0000 0000
SPBRGH
BRG15
BRG14
BRG13
BRG12
BRG11
BRG10
BRG9
BRG8
0000 0000
0000 0000
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
TRISC
TXREG
TXSTA
Legend:
EUSART Transmit Data Register
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
0000 0000
0000 0000
0000 0010
0000 0010
x = unknown, – = unimplemented read as ‘0’. Shaded cells are not used for Synchronous Slave Reception.
DS41291F-page 176
© 2009 Microchip Technology Inc.
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12.5
EUSART Operation During Sleep
The EUSART WILL remain active during Sleep only in
the Synchronous Slave mode. All other modes require
the system clock and therefore cannot generate the
necessary signals to run the Transmit or Receive Shift
registers during Sleep.
Synchronous Slave mode uses an externally generated
clock to run the Transmit and Receive Shift registers.
12.5.1
SYNCHRONOUS RECEIVE DURING
SLEEP
To receive during Sleep, all the following conditions
must be met before entering Sleep mode:
• RCSTA and TXSTA Control registers must be
configured for Synchronous Slave Reception (see
Section 12.4.2.4 “Synchronous Slave
Reception Set-up:”).
• If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
• The RCIF interrupt flag must be cleared by reading RCREG to unload any pending characters in
the receive buffer.
Upon entering Sleep mode, the device will be ready to
accept data and clocks on the RX/DT and TX/CK pins,
respectively. When the data word has been completely
clocked in by the external device, the RCIF interrupt
flag bit of the PIR1 register will be set. Thereby, waking
the processor from Sleep.
12.5.2
SYNCHRONOUS TRANSMIT
DURING SLEEP
To transmit during Sleep, all the following conditions
must be met before entering Sleep mode:
• RCSTA and TXSTA Control registers must be
configured for Synchronous Slave Transmission
(see Section 12.4.2.2 “Synchronous Slave
Transmission Set-up:”).
• The TXIF interrupt flag must be cleared by writing
the output data to the TXREG, thereby filling the
TSR and transmit buffer.
9. If interrupts are desired, set the TXIE bit of the
PIE1 register and the PEIE bit of the INTCON
register.
• Interrupt enable bits TXIE of the PIE1 register and
PEIE of the INTCON register must set.
Upon entering Sleep mode, the device will be ready to
accept clocks on TX/CK pin and transmit data on the
RX/DT pin. When the data word in the TSR has been
completely clocked out by the external device, the
pending byte in the TXREG will transfer to the TSR and
the TXIF flag will be set. Thereby, waking the processor
from Sleep. At this point, the TXREG is available to
accept another character for transmission, which will
clear the TXIF flag.
Upon waking from Sleep, the instruction following the
SLEEP instruction will be executed. If the GIE global
interrupt enable bit is also set then the Interrupt Service
Routine at address 0004h will be called.
Upon waking from Sleep, the instruction following the
SLEEP instruction will be executed. If the GIE global
interrupt enable bit of the INTCON register is also set,
then the Interrupt Service Routine at address 004h will
be called.
© 2009 Microchip Technology Inc.
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NOTES:
DS41291F-page 178
© 2009 Microchip Technology Inc.
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13.0
MASTER SYNCHRONOUS
SERIAL PORT (MSSP)
MODULE
13.1
Master SSP (MSSP) Module
Overview
The Master Synchronous Serial Port (MSSP) module is
a serial interface useful for communicating with other
peripheral or microcontroller devices. These peripheral
devices may be Serial EEPROMs, shift registers,
display drivers, A/D converters, etc. The MSSP module
can operate in one of two modes:
• Serial Peripheral Interface (SPI)
• Inter-Integrated CircuitTM (I2CTM)
- Full Master mode
- Slave mode (with general address call).
The I2C interface supports the following modes in
hardware:
• Master mode
• Multi-Master mode
• Slave mode.
13.2
Control Registers
The MSSP module has three associated registers.
These include a STATUS register and two control
registers.
Register 13-1 shows the MSSP STATUS register
(SSPSTAT), Register 13-2 shows the MSSP Control
Register 1 (SSPCON), and Register 13-3 shows the
MSSP Control Register 2 (SSPCON2).
© 2009 Microchip Technology Inc.
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REGISTER 13-1:
SSPSTAT: SSP 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’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7
x = Bit is unknown
SMP: Sample bit
SPI Master mode:
1 = Input data sampled at end of data output time
0 = Input data sampled at middle of data output time
SPI Slave mode:
SMP must be cleared when SPI is used in Slave mode
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
CKP = 0:
1 = Data transmitted on rising edge of SCK
0 = Data transmitted on falling edge of SCK
CKP = 1:
1 = Data transmitted on falling edge of SCK
0 = Data transmitted on rising edge of SCK
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 MSSP module is disabled, SSPEN 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 MSSP module is disabled, SSPEN 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 MSSP 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 SSPADD 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, SSPBUF is full
0 = Receive not complete, SSPBUF is empty
Transmit (I2 C mode only):
1 = Data transmit in progress (does not include the ACK and Stop bits), SSPBUF is full
0 = Data transmit complete (does not include the ACK and Stop bits), SSPBUF is empty
DS41291F-page 180
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REGISTER 13-2:
SSPCON: SSP 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
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
WCOL: Write Collision Detect bit
Master mode:
1 = A write to the SSPBUF register was attempted while the I2C conditions were not valid for a transmission to be started
0 = No collision
Slave mode:
1 = The SSPBUF register is written while it is still transmitting the previous word (must be cleared in software)
0 = No collision
bit 6
SSPOV: Receive Overflow Indicator bit
In SPI mode:
1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of overflow, the data in SSPSR
is lost. Overflow can only occur in Slave mode. In Slave mode, the user must read the SSPBUF, 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 SSPBUF register (must be cleared in software).
0 = No overflow
In I2 C mode:
1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a “don’t care” in Transmit
mode (must be cleared in software).
0 = No overflow
bit 5
SSPEN: 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 SCK, SDO, SDI and SS as the source of the serial port pins
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 SDA and SCL pins as the source of the serial port pins
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:
SCK 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
bit 3-0
SSPM<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 = SCK pin, SS pin control enabled
0101 = SPI Slave mode, clock = SCK pin, SS pin control disabled, SS 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 * (SSPADD+1))
1001 = Load Mask function
1010 = Reserved
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
© 2009 Microchip Technology Inc.
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REGISTER 13-3:
SSPCON2: SSP CONTROL REGISTER 2
R/W-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
GCEN
ACKSTAT
ACKDT
ACKEN
RCEN
PEN
RSEN
SEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
GCEN: General Call Enable bit (in I2C Slave mode only)
1 = Enable interrupt when a general call address (0000h) is received in the SSPSR
0 = General call address disabled
bit 6
ACKSTAT: Acknowledge Status bit (in I2C Master mode only)
In Master Transmit mode:
1 = Acknowledge was not received from slave
0 = Acknowledge was received from slave
bit 5
ACKDT: Acknowledge Data bit (in I2C Master mode only)
In Master 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: Acknowledge Sequence Enable bit (in I2C Master mode only)
In Master Receive mode:
1 = Initiate Acknowledge sequence on SDA and SCL pins, and transmit ACKDT data bit.
Automatically cleared by hardware.
0 = Acknowledge sequence idle
bit 3
RCEN: Receive Enable bit (in I2C Master mode only)
1 = Enables Receive mode for I2C
0 = Receive idle
bit 2
PEN: Stop Condition Enable bit (in I2C Master mode only)
SCK Release Control:
1 = Initiate Stop condition on SDA and SCL pins. Automatically cleared by hardware.
0 = Stop condition Idle
bit 1
RSEN: Repeated Start Condition Enabled bit (in I2C Master mode only)
1 = Initiate Repeated Start condition on SDA and SCL pins. Automatically cleared by hardware.
0 = Repeated Start condition Idle
bit 0
SEN: Start Condition Enabled bit (in I2C Master mode only)
In Master mode:
1 = Initiate Start condition on SDA and SCL 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 SSPBUF may not be written (or writes to the SSPBUF are disabled).
DS41291F-page 182
© 2009 Microchip Technology Inc.
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13.3
SPI Mode
FIGURE 13-1:
The SPI mode allows 8 bits of data to be synchronously
transmitted and received, simultaneously. All four modes
of SPI are supported. To accomplish communication,
typically three pins are used:
MSSP BLOCK DIAGRAM
(SPI MODE)
Internal
Data Bus
Read
• Serial Data Out (SDO) – RC5/SDO
• Serial Data In (SDI) – RC4/SDI/SDA
• Serial Clock (SCK) – RC3/SCK/SCL
Write
SSPBUF Reg
Additionally, a fourth pin may be used when in any
Slave mode of operation:
SSPSR Reg
• Slave Select (SS) – RA5/SS/AN4
SDI
13.3.1
SDO
OPERATION
When initializing the SPI, several options need to be
specified. This is done by programming the appropriate
control bits SSPCON<5:0> and SSPSTAT<7:6>.
These control bits allow the following to be specified:
•
•
•
•
Master mode (SCK is the clock output)
Slave mode (SCK is the clock input)
Clock polarity (Idle state of SCK)
Data input sample phase (middle or end of data
output time)
• Clock edge (output data on rising/falling edge of
SCK)
• Clock rate (Master mode only)
• Slave Select mode (Slave mode only)
Figure 13-1 shows the block diagram of the MSSP
module, when in SPI mode.
Shift
Clock
bit 0
SS Control
Enable
SS
Edge
Select
2
Clock Select
SSPM<3:0>
SMP:CKE 4
TMR2 Output
2
2
Edge
Select
Prescaler TOSC
4, 16, 64
(
SCK
)
Data to TX/RX in SSPSR
TRIS bit
Note: I/O pins have diode protection to VDD and VSS.
The MSSP consists of a transmit/receive shift register
(SSPSR) and a buffer register (SSPBUF). The SSPSR
shifts the data in and out of the device, MSb first. The
SSPBUF holds the data that was written to the SSPSR,
until the received data is ready. Once the 8 bits of data
have been received, that byte is moved to the SSPBUF
register. Then, the buffer full-detect bit BF of the SSPSTAT register and the interrupt flag bit SSPIF of the
PIR1 register are set. This double buffering of the
received data (SSPBUF) allows the next byte to start
reception before reading the data that was just
received. Any write to the SSPBUF register during
transmission/reception of data will be ignored, and the
write collision detect bit WCOL of the SSPCON register
will be set. User software must clear the WCOL bit so
that it can be determined if the following write(s) to the
SSPBUF register completed successfully.
© 2009 Microchip Technology Inc.
DS41291F-page 183
PIC16F882/883/884/886/887
When the application software is expecting to receive
valid data, the SSPBUF should be read before the next
byte of data to transfer is written to the SSPBUF. The
buffer full bit BF of the SSPSTAT register indicates
when SSPBUF has been loaded with the received data
(transmission is complete). When the SSPBUF is read,
the BF bit is cleared. This data may be irrelevant if the
SPI is only a transmitter. Generally, the MSSP Interrupt
is used to determine when the transmission/reception
has completed. The SSPBUF must be read and/or
written. If the interrupt method is not going to be used,
then software polling can be done to ensure that a write
collision does not occur. Example 13-1 shows the
loading of the SSPBUF (SSPSR) for data transmission.
The SSPSR is not directly readable or writable, and
can only be accessed by addressing the SSPBUF
register. Additionally, the MSSP STATUS register
(SSPSTAT register) indicates the various status
conditions.
EXAMPLE 13-1:
13.3.2
ENABLING SPI I/O
To enable the serial port, SSP Enable bit SSPEN of the
SSPCON register must be set. To reset or reconfigure
SPI mode, clear the SSPEN bit, re-initialize the
SSPCON registers, and then set the SSPEN bit. This
configures the SDI, SDO, SCK and SS 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. That is:
• SDI is automatically controlled by the SPI module
• SDO must have TRISC<5> bit cleared
• SCK (Master mode) must have TRISC<3> bit
cleared
• SCK (Slave mode) must have TRISC<3> bit set
• SS must have TRISA<5> bit set
Any serial port function that is not desired may be
overridden by programming the corresponding data
direction (TRIS) register to the opposite value.
LOADING THE SSPBUF (SSPSR) REGISTER
LOOP BTFSS SSPSTAT, BF
GOTO LOOP
MOVF SSPBUF, W
;Has data been received (transmit complete)?
;No
;WREG reg = contents of SSPBUF
MOVWF RXDATA
;Save in user RAM, if data is meaningful
MOVF TXDATA, W
MOVWF SSPBUF
;W reg = contents of TXDATA
;New data to xmit
DS41291F-page 184
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.3.3
MASTER MODE
The clock polarity is selected by appropriately programming the CKP bit of the SSPCON register. This, then,
would give waveforms for SPI communication as
shown in Figure 13-2, Figure 13-4 and Figure 13-5,
where the MSb is transmitted first. In Master mode, the
SPI clock rate (bit rate) is user programmable to be one
of the following:
The master can initiate the data transfer at any time
because it controls the SCK. The master determines
when the slave is to broadcast data by the software
protocol.
In Master mode, the data is transmitted/received as
soon as the SSPBUF register is written to. If the SPI is
only going to receive, the SDO output could be disabled (programmed as an input). The SSPSR register
will continue to shift in the signal present on the SDI pin
at the programmed clock rate. As each byte is
received, it will be loaded into the SSPBUF register as
a normal received byte (interrupts and Status bits
appropriately set). This could be useful in receiver
applications as a “Line Activity Monitor” mode.
FIGURE 13-2:
•
•
•
•
FOSC/4 (or TCY)
FOSC/16 (or 4 • TCY)
FOSC/64 (or 16 • TCY)
Timer2 output/2
This allows a maximum data rate (at 40 MHz) of
10.00 Mbps.
Figure 13-2 shows the waveforms for Master mode.
When the CKE bit of the SSPSTAT register is set, the
SDO data is valid before there is a clock edge on SCK.
The change of the input sample is shown based on the
state of the SMP bit of the SSPSTAT register. The time
when the SSPBUF is loaded with the received data is
shown.
SPI MODE WAVEFORM (MASTER MODE)
Write to
SSPBUF
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
4 Clock
Modes
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
SDO
(CKE = 0)
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDO
(CKE = 1)
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SDI
(SMP = 0)
bit 0
bit 7
Input
Sample
(SMP = 0)
SDI
(SMP = 1)
bit7
bit 0
Input
Sample
(SMP = 1)
SSPIF
SSPSR to
SSPBUF
© 2009 Microchip Technology Inc.
Next Q4 Cycle
after Q2↓
DS41291F-page 185
PIC16F882/883/884/886/887
13.3.4
SLAVE MODE
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched, the SSPIF interrupt flag bit of the
PIR1 register is set.
While in Slave mode, the external clock is supplied by
the external clock source on the SCK pin. This external
clock must meet the minimum high and low times, as
specified in the electrical specifications.
While in Sleep mode, the slave can transmit/receive
data. When a byte is received, the device will wake-up
from Sleep.
13.3.5
SLAVE SELECT
SYNCHRONIZATION
The SS pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with SS pin control
enabled (SSPCON<3:0> = 04h). The pin must not
be driven low for the SS pin to function as an input.
The Data Latch must be high. When the SS pin is
low, transmission and reception are enabled and
the SDO pin is driven. When the SS pin goes high,
FIGURE 13-3:
the SDO 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 SS
pin control enabled (SSPCON<3:0> =
0100), the SPI module will reset if the SS
pin is set to VDD.
2: If the SPI is used in Slave mode with CKE
set (SSPSTAT register), then the SS pin
control must be enabled.
When the SPI module resets, the bit counter is forced
to ‘0’. This can be done by either forcing the SS pin to
a high level, or clearing the SSPEN bit.
To emulate two-wire communication, the SDO pin can
be connected to the SDI pin. When the SPI needs to
operate as a receiver, the SDO pin can be configured
as an input. This disables transmissions from the SDO.
The SDI can always be left as an input (SDI function),
since it cannot create a bus conflict.
SLAVE SYNCHRONIZATION WAVEFORM
SS
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
SDO
SDI
(SMP = 0)
bit 7
bit 6
bit 7
bit 0
bit 0
bit 7
bit 7
Input
Sample
(SMP = 0)
SSPIF
SSPSR to
SSPBUF
DS41291F-page 186
Next Q4 Cycle
after Q2↓
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 13-4:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
SS
Optional
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
SDO
bit 7
SDI
(SMP = 0)
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
bit 0
bit 7
Input
Sample
(SMP = 0)
SSPIF
Next Q4 Cycle
after Q2↓
SSPSR to
SSPBUF
FIGURE 13-5:
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
SS
Required
SCK
(CKP = 0
CKE = 1)
SCK
(CKP = 1
CKE = 1)
Write to
SSPBUF
SDO
SDI
(SMP = 0)
bit 7
bit 6
bit 7
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
bit 0
Input
Sample
(SMP = 0)
SSPIF
SSPSR to
SSPBUF
© 2009 Microchip Technology Inc.
Next Q4 Cycle
after Q2↓
DS41291F-page 187
PIC16F882/883/884/886/887
13.3.6
SLEEP OPERATION
13.3.8
In Master mode, all module clocks are halted, and the
transmission/reception will remain in that state until the
device wakes from Sleep. After the device returns to
normal mode, the module will continue to transmit/
receive data.
Table 13-1 shows the compatibility between the
standard SPI modes and the states of the CKP and
CKE control bits.
TABLE 13-1:
In 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 eight bits have been received, the MSSP
interrupt flag bit will be set and, if enabled, will wake the
device from Sleep.
13.3.7
SPI BUS MODES
Control Bits State
Standard SPI Mode
Terminology
CKP
CKE
0, 0
0, 1
1, 0
1, 1
0
0
1
1
1
0
1
0
EFFECTS OF A RESET
There is also a SMP bit that controls when the data will
be sampled.
A Reset disables the MSSP module and terminates the
current transfer.
TABLE 13-2:
Name
BUS MODE COMPATIBILITY
REGISTERS ASSOCIATED WITH SPI OPERATION
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
RESETS
GIE/GIEH
PEIE/GIEL
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000u
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
0000 0000
0000 0000
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
0000 0000
xxxx xxxx
uuuu uuuu
INTCON
SSPBUF
Synchronous Serial Port Receive Buffer/Transmit Register
SSPCON
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
0000 0000
SSPSTAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000
0000 0000
TRISA
TRISA7
TRISA6
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
1111 1111
1111 1111
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
TRISC2
TRISC1
TRISC0
1111 1111
1111 1111
Legend:
Note 1:
x = unknown, u = unchanged, – = unimplemented, read as ‘0’. Shaded cells are not used by the MSSP in SPI mode.
Bit 6 of PORTA, LATA and TRISA are enabled in ECIO and RCIO Oscillator modes only. In all other oscillator modes, they are disabled and
read ‘0’.
DS41291F-page 188
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4
MSSP I2C Operation
The MSSP module in I 2C mode, fully implements all
master and slave functions (including general call
support) and provides interrupts on Start and Stop bits in
hardware, to determine a free bus (Multi-Master mode).
The MSSP module implements the standard mode
specifications, as well as 7-bit and 10-bit addressing.
Two pins are used for data transfer. These are the RC3/
SCK/SCL pin, which is the clock (SCL), and the RC4/
SDI/SDA pin, which is the data (SDA). The user must
configure these pins as inputs or outputs through the
TRISC<4:3> bits.
The MSSP module functions are enabled by setting
MSSP Enable bit SSPEN of the SSPCON register.
FIGURE 13-6:
MSSP BLOCK DIAGRAM
(I2C MODE)
Internal
Data Bus
Read
Write
SSPBUF Reg
RC3/SCK/SCL
SSPSR Reg
MSb
LSb
Match Detect
I2C Master mode, clock = OSC/4 (SSPADD +1)
I 2C Slave mode (7-bit address)
I 2C Slave mode (10-bit address)
I 2C Slave mode (7-bit address), with Start and
Stop bit interrupts enabled
• I 2C Slave mode (10-bit address), with Start and
Stop bit interrupts enabled
• I 2C firmware controlled master operation, slave is
idle
•
•
•
•
Selection of any I 2C mode with the SSPEN bit set,
forces the SCL and SDA pins to be open drain,
provided these pins are programmed to be inputs by
setting the appropriate TRISC bits.
13.4.1
In Slave mode, the SCL and SDA pins must be
configured as inputs (TRISC<4:3> set). The MSSP
module will override the input state with the output data
when required (slave-transmitter).
Addr Match
If either or both of the following conditions are true, the
MSSP module will not give this ACK pulse:
a)
SSPMSK Reg
b)
SSPADD Reg
Start and
Stop bit Detect
Note:
SLAVE MODE
When an address is matched, or the data transfer after
an address match is received, the hardware
automatically will generate the Acknowledge (ACK)
pulse and load the SSPBUF register with the received
value currently in the SSPSR register.
Shift
Clock
RC4/
SDI/
SDA
The SSPCON register allows control of the I 2C
operation. The SSPM<3:0> mode selection bits
(SSPCON register) allow one of the following I 2C modes
to be selected:
Set, Reset
S, P bits
(SSPSTAT Reg)
I/O pins have diode protection to VDD and VSS.
The MSSP module has these six registers for I2C
operation:
The buffer full bit BF (SSPCON register) was set
before the transfer was received.
The overflow bit SSPOV (SSPCON register)
was set before the transfer was received.
In this event, the SSPSR register value is not loaded
into the SSPBUF, but bit SSPIF of the PIR1 register is
set. The BF bit is cleared by reading the SSPBUF
register, while bit SSPOV is cleared through software.
The SCL clock input must have a minimum high and
low for proper operation. The high and low times of the
I2C specification, as well as the requirement of the
MSSP module, are shown in timing parameter #100
and parameter #101.
•
•
•
•
•
MSSP Control Register 1 (SSPCON)
MSSP Control Register 2 (SSPCON2)
MSSP STATUS register (SSPSTAT)
Serial Receive/Transmit Buffer (SSPBUF)
MSSP Shift Register (SSPSR) – Not directly
accessible
• MSSP Address register (SSPADD)
• MSSP Mask register (SSPMSK)
© 2009 Microchip Technology Inc.
DS41291F-page 189
PIC16F882/883/884/886/887
13.4.1.1
Addressing
Once the MSSP module has been enabled, it waits for
a Start condition to occur. Following the Start condition,
the eight bits are shifted into the SSPSR register. All
incoming bits are sampled with the rising edge of the
clock (SCL) line. The value of register SSPSR<7:1> is
compared to the value of the SSPADD register. The
address is compared on the falling edge of the eighth
clock (SCL) pulse. If the addresses match, and the BF
and SSPOV bits are clear, the following events occur:
a)
b)
c)
d)
The SSPSR register value is loaded into the
SSPBUF register.
The buffer full bit BF is set.
An ACK pulse is generated.
MSSP interrupt flag bit, SSPIF of the PIR1
register, is set on the falling edge of the ninth
SCL pulse (interrupt is generated, if enabled).
In 10-bit address mode, two address bytes need to be
received by the slave. The five Most Significant bits
(MSb) of the first address byte specify if this is a 10-bit
address. The R/W bit (SSPSTAT register) must specify
a write so the slave device will receive the second
address byte. For a 10-bit address, the first byte would
equal ‘1111 0 A9 A8 0’, where A9 and A8 are the
two MSb’s of the address.
The sequence of events for 10-bit addressing is as
follows, with steps 7-9 for slave-transmitter:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Receive first (high) byte of address (bit SSPIF of
the PIR1 register and bits BF and UA of the
SSPSTAT register are set).
Update the SSPADD register with second (low)
byte of address (clears bit UA and releases the
SCL line).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive second (low) byte of address (bits
SSPIF, BF, and UA are set).
Update the SSPADD register with the first (high)
byte of address. If match releases SCL line, this
will clear bit UA.
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
Receive Repeated Start condition.
Receive first (high) byte of address (bits SSPIF
and BF are set).
Read the SSPBUF register (clears bit BF) and
clear flag bit SSPIF.
13.4.1.2
When the address byte overflow condition exists, then
no Acknowledge (ACK) pulse is given. An overflow
condition is defined as either bit BF (SSPSTAT register)
is set, or bit SSPOV (SSPCON register) is set.
An MSSP interrupt is generated for each data transfer
byte. Flag bit SSPIF of the PIR1 register must be
cleared in software. The SSPSTAT register is used to
determine the status of the byte.
13.4.1.3
Transmission
When the R/W bit of the incoming address byte is set
and an address match occurs, the R/W bit of the
SSPSTAT register is set. The received address is
loaded into the SSPBUF register. The ACK pulse will
be sent on the ninth bit and pin RC3/SCK/SCL is held
low. The transmit data must be loaded into the
SSPBUF register, which also loads the SSPSR register. Then pin RC3/SCK/SCL should be enabled by setting bit CKP (SSPCON register). The master must
monitor the SCL pin prior to asserting another clock
pulse. The slave devices may be holding off the master
by stretching the clock. The eight data bits are shifted
out on the falling edge of the SCL input. This ensures
that the SDA signal is valid during the SCL high time
(Figure 13-8).
An MSSP interrupt is generated for each data transfer
byte. The SSPIF bit must be cleared in software and
the SSPSTAT register is used to determine the status
of the byte. The SSPIF bit is set on the falling edge of
the ninth clock pulse.
As a slave-transmitter, the ACK pulse from the masterreceiver is latched on the rising edge of the ninth SCL
input pulse. If the SDA line is high (not ACK), then the
data transfer is complete. When the ACK is latched by
the slave, the slave logic is reset and the slave monitors for another occurrence of the Start bit. If the SDA
line was low (ACK), the transmit data must be loaded
into the SSPBUF register, which also loads the SSPSR
register. Pin RC3/SCK/SCL should be enabled by
setting bit CKP.
Reception
When the R/W bit of the address byte is clear and an
address match occurs, the R/W bit of the SSPSTAT
register is cleared. The received address is loaded into
the SSPBUF register.
DS41291F-page 190
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
I 2C™ SLAVE MODE WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
FIGURE 13-7:
Receiving Address R/W = 0
Receiving Data
Receiving Data
Not ACK
ACK
ACK
A7 A6 A5 A4 A3 A2 A1
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
SDA
SCL
1
S
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
SSPIF
P
Bus Master
Terminates
Transfer
BF
Cleared in software
SSPBUF register is read
SSPOV
Bit SSPOV is set because the SSPBUF register is still full
ACK is not sent
I 2C™ SLAVE MODE WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
FIGURE 13-8:
Receiving Address
SDA
SCL
A7
S
A6
1
2
Data in
Sampled
R/W = 1
A5
A4
A3
A2
A1
3
4
5
6
7
ACK
8
9
R/W = 0
Not ACK
Transmitting Data
D7
1
SCL held low
while CPU
responds to SSPIF
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
9
P
SSPIF
BF
Cleared in software
SSPBUF is written in software
From SSP Interrupt
Service Routine
CKP
Set bit after writing to SSPBUF
(the SSPBUF must be written to
before the CKP bit can be set)
© 2009 Microchip Technology Inc.
DS41291F-page 191
PIC16F882/883/884/886/887
13.4.2
GENERAL CALL ADDRESS
SUPPORT
If the general call address matches, the SSPSR is
transferred to the SSPBUF, the BF bit is set (eighth bit),
and on the falling edge of the ninth bit (ACK bit), the
SSPIF interrupt flag bit is set.
The addressing procedure for the I2C bus is such that,
the first byte after the Start condition usually determines which device will be the slave addressed by the
master. The exception is the general call address,
which can address all devices. When this address is
used, all devices should, in theory, respond with an
Acknowledge.
When the interrupt is serviced, the source for the interrupt can be checked by reading the contents of the
SSPBUF. The value can be used to determine if the
address was device specific or a general call address.
In 10-bit mode, the SSPADD is required to be updated
for the second half of the address to match, and the UA
bit is set (SSPSTAT register). If the general call address
is sampled when the GCEN bit is set, and while the
slave is configured in 10-bit address mode, then the
second half of the address is not necessary. The UA bit
will not be set, and the slave will begin receiving data
after the Acknowledge (Figure 13-9).
The general call address is one of eight addresses
reserved for specific purposes by the I2C protocol. It
consists of all 0’s with R/W = 0.
The general call address is recognized (enabled) when
the General Call Enable (GCEN) bit is set (SSPCON2
register). Following a Start bit detect, eight bits are
shifted into the SSPSR and the address is compared
against the SSPADD. It is also compared to the general
call address and fixed in hardware.
FIGURE 13-9:
SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT ADDRESS)
Address is compared to General Call Address
after ACK, set interrupt
R/W = 0
ACK D7
General Call Address
SDA
Receiving Data
ACK
D6
D5
D4
D3
D2
D1
D0
2
3
4
5
6
7
8
SCL
S
1
2
3
4
5
6
7
8
9
1
9
SSPIF
BF
Cleared in software
SSPBUF is read
SSPOV
‘0’
GCEN
‘1’
DS41291F-page 192
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
MASTER MODE
13.4.4
Master mode of operation is supported by interrupt
generation on the detection of the Start and Stop
conditions. The Stop (P) and Start (S) bits are cleared
from a Reset, or when the MSSP module is disabled.
Control of the I 2C bus may be taken when the P bit is
set, or the bus is idle, with both the S and P bits clear.
Master mode is enabled by setting and clearing the
appropriate SSPM bits in SSPCON and by setting the
SSPEN bit. Once Master mode is enabled, the user
has the following six options:
1.
2.
In Master mode, the SCL and SDA lines are manipulated by the MSSP hardware.
4.
5.
6.
Start condition
Stop condition
Data transfer byte transmitted/received
Acknowledge transmit
Repeated Start condition
FIGURE 13-10:
Assert a Start condition on SDA and SCL.
Assert a Repeated Start condition on SDA and
SCL.
Write to the SSPBUF register initiating
transmission of data/address.
Generate a Stop condition on SDA and SCL.
Configure the I2C port to receive data.
Generate an Acknowledge condition at the end
of a received byte of data.
3.
The following events will cause SSP Interrupt Flag bit,
SSPIF, to be set (SSP Interrupt if enabled):
•
•
•
•
•
I2C™ MASTER MODE SUPPORT
Note:
The MSSP module, when configured in I2C
Master mode, does not allow queueing of
events. For instance, the user is not
allowed to initiate a Start condition and
immediately write the SSPBUF register to
imitate transmission, before the Start
condition is complete. In this case, the
SSPBUF will not be written to and the
WCOL bit will be set, indicating that a write
to the SSPBUF did not occur.
MSSP BLOCK DIAGRAM (I2C™ MASTER MODE)
Internal
Data Bus
Read
SSPM<3:0>
SSPADD<6:0>
Write
SSPBUF
Baud
Rate
Generator
Shift
Clock
SDA
SDA In
SCL In
Bus Collision
MSb
LSb
Start bit, Stop bit,
Acknowledge
Generate
Start bit Detect
Stop bit Detect
Write Collision Detect
Clock Arbitration
State Counter for
End of XMIT/RCV
Clock Cntl
SCL
Receive Enable
SSPSR
Clock Arbitrate/WCOL Detect
(hold off clock source)
13.4.3
Set/Reset, S, P, WCOL (SSPSTAT)
Set SSPIF, BCLIF
Reset ACKSTAT, PEN (SSPCON2)
Note: I/O pins have diode protection to VDD and VSS.
© 2009 Microchip Technology Inc.
DS41291F-page 193
PIC16F882/883/884/886/887
13.4.4.1
I2C™ Master Mode Operation
The master device generates all of the serial clock
pulses and the Start and Stop conditions. A transfer is
ended with a Stop condition or with a Repeated Start
condition. Since the Repeated Start condition is also
the beginning of the next serial transfer, the I2C bus will
not be released.
In Master Transmitter mode, serial data is output
through SDA, while SCL 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 eight 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 receive bit. Serial
data is received via SDA, while SCL outputs the serial
clock. Serial data is received eight bits at a time. After
each byte is received, an Acknowledge bit is transmitted. Start and Stop conditions indicate the beginning
and end of transmission.
The Baud Rate Generator used for the SPI mode operation is now used to set the SCL clock frequency for
either 100 kHz, 400 kHz, or 1 MHz I2C operation. The
Baud Rate Generator reload value is contained in the
lower 7 bits of the SSPADD register. The Baud Rate
Generator will automatically begin counting on a write
to the SSPBUF. Once the given operation is complete
(i.e., transmission of the last data bit is followed by
ACK), the internal clock will automatically stop counting
and the SCL pin will remain in its last state.
DS41291F-page 194
A typical transmit sequence would go as follows:
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
The user generates a Start condition by setting
the Start Enable (SEN) bit (SSPCON2 register).
SSPIF is set. The MSSP module will wait the
required start time before any other operation
takes place.
The user loads the SSPBUF with the address to
transmit.
Address is shifted out the SDA pin until all eight
bits are transmitted.
The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
ACKSTAT bit (SSPCON2 register).
The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the SSPIF
bit.
The user loads the SSPBUF with eight bits of
data.
Data is shifted out the SDA pin until all eight bits
are transmitted.
The MSSP module shifts in the ACK bit from the
slave device and writes its value into the
ACKSTAT bit (SSPCON2 register).
The MSSP module generates an interrupt at the
end of the ninth clock cycle by setting the SSPIF
bit.
The user generates a Stop condition by setting
the Stop Enable bit PEN (SSPCON2 register).
Interrupt is generated once the Stop condition is
complete.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4.5
BAUD RATE GENERATOR
In I2C Master mode, the reload value for the BRG is
located in the lower 7 bits of the SSPADD register
(Figure 13-11). When the BRG is loaded with this
value, the BRG counts down to 0 and stops until
another reload has taken place. The BRG count is
decremented twice per instruction cycle (TCY) on the
Q2 and Q4 clocks. In I2C Master mode, the BRG is
reloaded automatically. If clock arbitration is taking
place, for instance, the BRG will be reloaded when the
SCL pin is sampled high (Figure 13-12).
FIGURE 13-11:
BAUD RATE GENERATOR BLOCK DIAGRAM
SSPM<3:0>
SSPM<3:0>
Reload
SCL
Control
CLKOUT
FIGURE 13-12:
SSPADD<6:0>
Reload
BRG Down Counter
FOSC/4
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
SDA
DX
DX-1
SCL de-asserted but slave holds
SCL low (clock arbitration)
SCL allowed to transition high
SCL
BRG decrements on
Q2 and Q4 cycles
BRG
Value
03h
02h
01h
00h (hold off)
03h
02h
SCL is sampled high, reload takes
place and BRG starts its count
BRG
Reload
© 2009 Microchip Technology Inc.
DS41291F-page 195
PIC16F882/883/884/886/887
13.4.6
I2C™ MASTER MODE START
CONDITION TIMING
13.4.6.1
If the user writes the SSPBUF when a Start sequence
is in progress, the WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
To initiate a Start condition, the user sets the Start Condition Enable bit SEN of the SSPCON2 register. If the
SDA and SCL pins are sampled high, the Baud Rate
Generator is reloaded with the contents of
SSPADD<6:0> and starts its count. If SCL and SDA are
both sampled high when the Baud Rate Generator
times out (TBRG), the SDA pin is driven low. The action
of the SDA being driven low, while SCL is high, is the
Start condition, and causes the S bit of the SSPSTAT
register to be set. Following this, the Baud Rate Generator is reloaded with the contents of SSPADD<6:0>
and resumes its count. When the Baud Rate Generator
times out (TBRG), the SEN bit of the SSPCON2 register
will be automatically cleared by hardware, the Baud
Rate Generator is suspended leaving the SDA line held
low and the Start condition is complete.
Note:
WCOL Status Flag
Note:
Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPCON2 is disabled until the Start
condition is complete.
If, at the beginning of the Start condition,
the SDA and SCL pins are already sampled low, or if during the Start condition the
SCL line is sampled low before the SDA
line is driven low, a bus collision occurs, the
Bus Collision Interrupt Flag, BCLIF, is set,
the Start condition is aborted, and the I2C
module is reset into its Idle state.
FIGURE 13-13:
FIRST START BIT TIMING
Set S bit (SSPSTAT)
Write to SEN bit occurs here
SDA = 1,
SCL = 1
TBRG
At completion of Start bit,
hardware clears SEN bit
and sets SSPIF bit
TBRG
Write to SSPBUF occurs here
1st Bit
2nd Bit
SDA
TBRG
SCL
TBRG
S
DS41291F-page 196
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4.7
I2C™ MASTER MODE REPEATED
START CONDITION TIMING
Note 1: If RSEN is programmed while any other
event is in progress, it will not take effect.
A Repeated Start condition occurs when the RSEN bit
(SSPCON2 register) is programmed high and the I2C
logic module is in the Idle state. When the RSEN bit is
set, the SCL pin is asserted low. When the SCL pin is
sampled low, the Baud Rate Generator is loaded with
the contents of SSPADD<5:0> and begins counting.
The SDA pin is released (brought high) for one Baud
Rate Generator count (TBRG). When the Baud Rate
Generator times out, if SDA is sampled high, the SCL
pin will be de-asserted (brought high). When SCL is
sampled high, the Baud Rate Generator is reloaded
with the contents of SSPADD<6:0> and begins counting. SDA and SCL must be sampled high for one TBRG.
This action is then followed by assertion of the SDA pin
(SDA = 0) for one TBRG, while SCL is high. Following
this, the RSEN bit (SSPCON2 register) will be automatically cleared and the Baud Rate Generator will not be
reloaded, leaving the SDA pin held low. As soon as a
Start condition is detected on the SDA and SCL pins,
the S bit (SSPSTAT register) will be set. The SSPIF bit
will not be set until the Baud Rate Generator has timed
out.
2: A bus collision during the Repeated Start
condition occurs if:
• SDA is sampled low when SCL goes
from low-to-high.
• SCL goes low before SDA is
asserted low. This may indicate that
another master is attempting to
transmit a data “1”.
Immediately following the SSPIF bit getting set, the
user may write the SSPBUF with the 7-bit address in
7-bit mode, or the default first address in 10-bit mode.
After the first eight bits are transmitted and an ACK is
received, the user may then transmit an additional eight
bits of address (10-bit mode), or eight bits of data (7-bit
mode).
13.4.7.1
If the user writes the SSPBUF when a Repeated Start
sequence is in progress, the WCOL is set and the contents of the buffer are unchanged (the write doesn’t
occur).
Note:
FIGURE 13-14:
WCOL Status Flag
Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPCON2 is disabled until the Repeated
Start condition is complete.
REPEAT START CONDITION WAVEFORM
Set S (SSPSTAT<3>)
Write to SSPCON2
occurs here,
SDA = 1,
SCL (no change)
SDA = 1,
SCL = 1
TBRG
TBRG
At completion of Start bit,
hardware clear RSEN bit
and set SSPIF
TBRG
1st bit
SDA
Falling edge of ninth clock
End of Xmit
SCL
Write to SSPBUF occurs here
TBRG
TBRG
Sr = Repeated Start
© 2009 Microchip Technology Inc.
DS41291F-page 197
PIC16F882/883/884/886/887
13.4.8
I2C™ MASTER MODE
TRANSMISSION
Transmission of a data byte, a 7-bit address, or the
other half of a 10-bit address, is accomplished by simply writing a value to the SSPBUF register. This action
will set the Buffer Full 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 SDA pin after the falling edge of SCL is
asserted (see data hold time specification, parameter
106). SCL is held low for one Baud Rate Generator rollover count (TBRG). Data should be valid before SCL is
released high (see data setup time specification,
parameter 107). When the SCL pin is released high, it
is held that way for TBRG. The data on the SDA pin
must remain stable for that duration and some hold
time after the next falling edge of SCL. After the eighth
bit is shifted out (the falling edge of the eighth clock),
the BF bit is cleared and the master releases SDA,
allowing the slave device being addressed to respond
with an ACK bit during the ninth bit time, if an address
match occurs, or if data was received properly. The
status of ACK is written into the ACKDT bit on the falling edge of the ninth clock. If the master receives an
Acknowledge, the Acknowledge Status bit, ACKSTAT,
is cleared. If not, the bit is set. After the ninth clock, the
SSPIF bit is set and the master clock (Baud Rate Generator) is suspended until the next data byte is loaded
into the SSPBUF, leaving SCL low and SDA
unchanged (Figure 13-15).
After the write to the SSPBUF, each bit of the address
will be shifted out on the falling edge of SCL, until all
seven address bits and the R/W bit, are completed. On
the falling edge of the eighth clock, the master will deassert the SDA pin, allowing the slave to respond with
an Acknowledge. On the falling edge of the ninth clock,
the master will sample the SDA pin to see if the address
was recognized by a slave. The status of the ACK bit is
loaded into the ACKSTAT Status bit (SSPCON2 register). Following the falling edge of the ninth clock transmission of the address, the SSPIF is set, the BF bit is
cleared and the Baud Rate Generator is turned off, until
another write to the SSPBUF takes place, holding SCL
low and allowing SDA to float.
13.4.8.1
BF Status Flag
13.4.8.3
ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit (SSPCON2
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.
13.4.9
I2C™ MASTER MODE RECEPTION
Master mode reception is enabled by programming the
Receive Enable bit, RCEN (SSPCON2 register).
Note:
The MSSP module must be in an Idle state
before the RCEN bit is set, or the RCEN bit
will be disregarded.
The Baud Rate Generator begins counting, and on
each rollover, the state of the SCL pin changes (highto-low/low-to-high) and data is shifted into the SSPSR.
After the falling edge of the eighth clock, the RCEN bit
is automatically cleared, the contents of the SSPSR are
loaded into the SSPBUF, the BF bit is set, the SSPIF
flag bit is set and the Baud Rate Generator is suspended from counting, holding SCL low. The MSSP is
now in Idle state, awaiting the next command. When
the buffer is read by the CPU, the BF 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 (SSPCON2 register).
13.4.9.1
BF Status Flag
In receive operation, the BF bit is set when an address
or data byte is loaded into SSPBUF from SSPSR. It is
cleared when the SSPBUF register is read.
13.4.9.2
SSPOV Status Flag
In receive operation, the SSPOV bit is set when eight
bits are received into the SSPSR and the BF bit is
already set from a previous reception.
13.4.9.3
WCOL Status Flag
If the user writes the SSPBUF when a receive is
already in progress (i.e., SSPSR is still shifting in a data
byte), the WCOL bit is set and the contents of the buffer
are unchanged (the write doesn’t occur).
In Transmit mode, the BF bit (SSPSTAT register) is set
when the CPU writes to SSPBUF, and is cleared when
all eight bits are shifted out.
13.4.8.2
WCOL Status Flag
If the user writes the SSPBUF when a transmit is
already in progress (i.e., SSPSR is still shifting out a
data byte), the WCOL is set and the contents of the buffer are unchanged (the write doesn’t occur). WCOL
must be cleared in software.
DS41291F-page 198
© 2009 Microchip Technology Inc.
© 2009 Microchip Technology Inc.
R/W
PEN
SEN
BF
SSPIF
SCL
SDA
S
A6
A5
A4
A3
A2
A1
3
4
5
Cleared in software
2
6
7
8
9
After Start condition, SEN cleared by hardware.
SSPBUF written
1
D7
1
SCL held low
while CPU
responds to SSPIF
ACK = 0
R/W = 0
SSPBUF 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
SSPBUF is written in software
Cleared in software service routine
From SSP interrupt
2
D6
Transmitting Data or Second Half
of 10-bit Address
From slave, clear ACKSTAT bit SSPCON2<6>
P
Cleared in software
9
ACK
ACKSTAT in
SSPCON2 = 1
FIGURE 13-15:
SEN = 0
Write SSPCON2<0> SEN = 1
Start condition begins
PIC16F882/883/884/886/887
I 2C™ MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS)
DS41291F-page 199
DS41291F-page 200
S
ACKEN
SSPOV
BF
SDA = 0, SCL = 1
while CPU
responds to SSPIF
SSPIF
SCL
SDA
1
2
4
5
6
Cleared in software
3
7
8
9
2
3
5
6
7
8
D0
9
ACK
2
3
4
5
6
7
8
Cleared in software
Set SSPIF interrupt
at end of Acknowledge
sequence
Cleared in
software
Set SSPIF at end
of receive
9
ACK is not sent
ACK
P
Bus Master
terminates
transfer
Set P bit
(SSPSTAT<4>)
and SSPIF
Set SSPIF interrupt
at end of Acknowledge sequence
PEN bit = 1
written here
SSPOV is set because
SSPBUF is still full
Data shifted in on falling edge of CLK
1
D7 D6 D5 D4 D3 D2 D1
D0
RCEN cleared
automatically
Set ACKEN start Acknowledge sequence
SDA = ACKDT = 1
Receiving Data from Slave
RCEN = 1 start
next receive
ACK from Master
SDA = ACKDT = 0
Last bit is shifted into SSPSR and
contents are unloaded into SSPBUF
Cleared in software
Set SSPIF interrupt
at end of receive
4
Cleared in software
1
Receiving Data from Slave
D7 D6 D5 D4 D3 D2 D1
RCEN cleared
automatically
Master configured as a receiver
by programming SSPCON2<3>, (RCEN = 1)
FIGURE 13-16:
SEN = 0
Write to SSPBUF occurs here
Start XMIT
ACK from Slave
Transmit Address to Slave R/W = 1
A7 A6 A5 A4 A3 A2 A1
ACK
Write to SSPCON2<0> (SEN = 1)
Begin Start Condition
Write to SSPCON2<4>
to start Acknowledge sequence
SDA = ACKDT (SSPCON2<5>) = 0
PIC16F882/883/884/886/887
I 2C™ MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4.10
ACKNOWLEDGE SEQUENCE TIMING
13.4.11
An Acknowledge sequence is enabled by setting the
Acknowledge Sequence Enable bit, ACKEN (SSPCON2
register). When this bit is set, the SCL pin is pulled low
and the contents of the Acknowledge Data bit (ACKDT)
is presented on the SDA 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 SCL pin is de-asserted (pulled high). When the SCL
pin is sampled high (clock arbitration), the Baud Rate
Generator counts for TBRG. The SCL pin is then pulled
low. Following this, the ACKEN bit is automatically
cleared, the Baud Rate Generator is turned off and the
MSSP module then goes into Idle mode (Figure 13-17).
13.4.10.1
A Stop bit is asserted on the SDA pin at the end of a
receive/transmit by setting the Stop Sequence Enable
bit, PEN (SSPCON2 register). At the end of a receive/
transmit, the SCL line is held low after the falling edge
of the ninth clock. When the PEN bit is set, the master
will assert the SDA line low. When the SDA line is sampled low, the Baud Rate Generator is reloaded and
counts down to 0. When the Baud Rate Generator
times out, the SCL pin will be brought high, and one
TBRG (Baud Rate Generator rollover count) later, the
SDA pin will be de-asserted. When the SDA pin is sampled high while SCL is high, the P bit (SSPSTAT register) is set. A TBRG later, the PEN bit is cleared and the
SSPIF bit is set (Figure 13-18).
13.4.11.1
WCOL Status Flag
WCOL Status Flag
If the user writes the SSPBUF when a Stop sequence
is in progress, then the WCOL bit is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
If the user writes the SSPBUF when an Acknowledge
sequence is in progress, then WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
FIGURE 13-17:
STOP CONDITION TIMING
ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here,
Write to SSPCON2
ACKEN = 1, ACKDT = 0
ACKEN automatically cleared
TBRG
TBRG
SDA
D0
SCL
ACK
8
9
SSPIF
Set SSPIF at the end
of receive
Cleared in
software
Cleared in
software
Set SSPIF at the end
of Acknowledge sequence
Note: TBRG = one Baud Rate Generator period.
© 2009 Microchip Technology Inc.
DS41291F-page 201
PIC16F882/883/884/886/887
FIGURE 13-18:
STOP CONDITION RECEIVE OR TRANSMIT MODE
SCL = 1 for TBRG, followed by SDA = 1 for TBRG
after SDA sampled high, P bit (SSPSTAT) is set
Write to SSPCON2
Set PEN
PEN bit (SSPCON2) is cleared by
hardware and the SSPIF bit is set
Falling edge of
9th clock
TBRG
SCL
SDA
ACK
P
TBRG
TBRG
TBRG
SCL brought high after TBRG
SDA asserted low before rising edge of clock
to set up Stop condition
Note: TBRG = one Baud Rate Generator period.
13.4.12
CLOCK ARBITRATION
13.4.13
Clock arbitration occurs when the master, during any
receive, transmit or Repeated Start/Stop condition, deasserts the SCL pin (SCL allowed to float high). When
the SCL pin is allowed to float high, the Baud Rate Generator (BRG) is suspended from counting until the SCL
pin is actually sampled high. When the SCL pin is sampled high, the Baud Rate Generator is reloaded with
the contents of SSPADD<6:0> and begins counting.
This ensures that the SCL 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 13-19).
FIGURE 13-19:
SLEEP OPERATION
While in Sleep mode, the I2C module can receive
addresses or data, and when an address match or
complete byte transfer occurs, wake the processor
from Sleep (if the MSSP interrupt is enabled).
13.4.14
EFFECT OF A RESET
A Reset disables the MSSP module and terminates the
current transfer.
CLOCK ARBITRATION TIMING IN MASTER TRANSMIT MODE
BRG overflow,
Release SCL,
If SCL = 1, load BRG with
SSPADD<6:0>, and start count
to measure high time interval
BRG overflow occurs,
Release SCL, Slave device holds SCL low
SCL = 1, BRG starts counting
clock high interval
SCL
SCL line sampled once every machine cycle (TOSC*4),
Hold off BRG until SCL is sampled high
SDA
TBRG
DS41291F-page 202
TBRG
TBRG
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4.15
MULTI-MASTER MODE
In Multi-Master mode, the interrupt generation on the
detection of the Start and Stop conditions allows the
determination of when the bus is free. The Stop (P) and
Start (S) bits are cleared from a Reset, or when the
MSSP module is disabled. Control of the I 2C bus may
be taken when the P bit (SSPSTAT register) is set, or
the bus is idle with both the S and P bits clear. When
the bus is busy, enabling the SSP Interrupt will generate the interrupt when the Stop condition occurs.
In Multi-Master operation, the SDA line must be monitored for arbitration, to see if the signal level is the
expected output level. This check is performed in hardware, with the result placed in the BCLIF bit.
Arbitration can be lost in the following states:
•
•
•
•
•
Address transfer
Data transfer
A Start condition
A Repeated Start condition
An Acknowledge condition
13.4.16
If a transmit was in progress when the bus collision
occurred, the transmission is halted, the BF bit is
cleared, the SDA and SCL lines are de-asserted, and
the SSPBUF can be written to. When the user services
the bus collision interrupt service routine, and if the I2C
bus is free, the user can resume communication by
asserting a Start condition.
If a Start, Repeated Start, Stop, or Acknowledge
condition was in progress when the bus collision
occurred, the condition is aborted, the SDA and SCL
lines are de-asserted, and the respective control bits in
the SSPCON2 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 SDA and SCL
pins. If a Stop condition occurs, the SSPIF bit will be
set.
MULTI -MASTER
COMMUNICATION, BUS
COLLISION, AND BUS
ARBITRATION
A write to the SSPBUF will start the transmission of
data at the first data bit, regardless of where the transmitter left off when the bus collision occurred.
Multi-Master mode support is achieved by bus arbitration. When the master outputs address/data bits onto
the SDA pin, arbitration takes place when the master
outputs a ‘1’ on SDA, by letting SDA float high and
another master asserts a ‘0’. When the SCL pin floats
high, data should be stable. If the expected data on
FIGURE 13-20:
SDA is a ‘1’ and the data sampled on the SDA pin = 0,
then a bus collision has taken place. The master will set
the Bus Collision Interrupt Flag (BCLIF) and reset the
I2C port to its Idle state (Figure 13-20).
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 SSPSTAT
register, or the bus is idle and the S and P bits are
cleared.
BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
Data changes
while SCL = 0
SDA line pulled low
by another source
SDA released
by master
Sample SDA,
While SCL is high, data doesn’t
match what is driven by the master,
Bus collision has occurred
SDA
SCL
Set bus collision
interrupt (BCLIF)
BCLIF
© 2009 Microchip Technology Inc.
DS41291F-page 203
PIC16F882/883/884/886/887
13.4.16.1
Bus Collision During a Start
Condition
During a Start condition, a bus collision occurs if:
a)
SDA or SCL are sampled low at the beginning of
the Start condition (Figure 13-21).
SCL is sampled low before SDA is asserted low
(Figure 13-22).
b)
During a Start condition, both the SDA and the SCL
pins are monitored, if:
the SDA pin is already low,
or the SCL pin is already low,
while SDA is high, a bus collision occurs, because it is
assumed that another master is attempting to drive a
data ‘1’ during the Start condition.
If the SDA pin is sampled low during this count, the
BRG is reset and the SDA line is asserted early
(Figure 13-23). If, however, a ‘1’ is sampled on the SDA
pin, the SDA pin is asserted low at the end of the BRG
count. The Baud Rate Generator is then reloaded and
counts down to 0, and during this time, if the SCL pin is
sampled as ‘0’, a bus collision does not occur. At the
end of the BRG count, the SCL pin is asserted low.
Note:
then:
the Start condition is aborted,
and the BCLIF flag is set,
and the MSSP module is reset to its Idle state
(Figure 13-21).
The Start condition begins with the SDA and SCL pins
de-asserted. When the SDA pin is sampled high, the
Baud Rate Generator is loaded from SSPADD<6:0>
and counts down to 0. If the SCL pin is sampled low
FIGURE 13-21:
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 SDA 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 (SDA ONLY)
SDA goes low before the SEN bit is set.
Set BCLIF,
S bit and SSPIF set because
SDA = 0, SCL = 1.
SDA
SCL
Set SEN, enable Start
condition if SDA = 1, SCL = 1.
SEN cleared automatically because of bus collision.
SSP module reset into Idle state.
SEN
BCLIF
SDA sampled low before
Start condition. Set BCLIF.
S bit and SSPIF set because
SDA = 0, SCL = 1.
SSPIF and BCLIF are
cleared in software.
S
SSPIF
SSPIF and BCLIF are
cleared in software.
DS41291F-page 204
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 13-22:
BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
TBRG
TBRG
SDA
Set SEN, enable Start
sequence if SDA = 1, SCL = 1
SCL
SCL = 0 before SDA = 0,
Bus collision occurs, set BCLIF
SEN
SCL =0 before BRG time-out,
Bus collision occurs, set BCLIF
BCLIF
Interrupt cleared
in software
S
‘0’
‘0’
SSPIF
‘0’
‘0’
FIGURE 13-23:
BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDA = 0, SCL = 1
Set S
Less than TBRG
SDA
Set SSPIF
TBRG
SDA pulled low by other master
Reset BRG and assert SDA
SCL
S
SCL pulled low after BRG
time-out
SEN
BCLIF
Set SEN, enable Start
sequence if SDA = 1, SCL = 1
‘0’
S
SSPIF
SDA = 0, SCL = 1
Set SSPIF
© 2009 Microchip Technology Inc.
Interrupts cleared
in software
DS41291F-page 205
PIC16F882/883/884/886/887
13.4.16.2
Bus Collision During a Repeated
Start Condition
If SDA is low, a bus collision has occurred (i.e, another
master is attempting to transmit a data ‘0’, see
Figure 13-24). If SDA is sampled high, the BRG is
reloaded and begins counting. If SDA goes from highto-low before the BRG times out, no bus collision
occurs because no two masters can assert SDA at
exactly the same time.
During a Repeated Start condition, a bus collision
occurs if:
a)
b)
A low level is sampled on SDA when SCL goes
from low level to high level.
SCL goes low before SDA is asserted low, indicating that another master is attempting to transmit a data ’1’.
If SCL goes from high-to-low before the BRG times out
and SDA 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
(Figure 13-25).
When the user de-asserts SDA and the pin is allowed
to float high, the BRG is loaded with SSPADD<6:0>
and counts down to 0. The SCL pin is then de-asserted,
and when sampled high, the SDA pin is sampled.
FIGURE 13-24:
If at the end of the BRG time-out, both SCL and SDA are
still high, the SDA pin is driven low and the BRG is
reloaded and begins counting. At the end of the count,
regardless of the status of the SCL pin, the SCL pin is
driven low and the Repeated Start condition is complete.
BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
SDA
SCL
Sample SDA when SCL goes high,
If SDA = 0, set BCLIF and release SDA and SCL
RSEN
BCLIF
Cleared in software
‘0’
S
‘0’
SSPIF
FIGURE 13-25:
BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG
TBRG
SDA
SCL
BCLIF
SCL goes low before SDA,
Set BCLIF, release SDA and SCL
Interrupt cleared
in software
RSEN
S
‘0’
SSPIF
DS41291F-page 206
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
13.4.16.3
Bus Collision During a Stop
Condition
The Stop condition begins with SDA asserted low.
When SDA is sampled low, the SCL pin is allowed to
float. When the pin is sampled high (clock arbitration),
the Baud Rate Generator is loaded with SSPADD<6:0>
and counts down to 0. After the BRG times out, SDA is
sampled. If SDA is sampled low, a bus collision has
occurred. This is due to another master attempting to
drive a data ‘0’ (Figure 13-26). If the SCL pin is sampled low before SDA is allowed to float high, a bus collision occurs. This is another case of another master
attempting to drive a data ‘0’ (Figure 13-27).
Bus collision occurs during a Stop condition if:
a)
b)
After the SDA pin has been de-asserted and
allowed to float high, SDA is sampled low after
the BRG has timed out.
After the SCL pin is de-asserted, SCL is
sampled low before SDA goes high.
FIGURE 13-26:
BUS COLLISION DURING A STOP CONDITION (CASE 1)
TBRG
TBRG
SDA sampled
low after TBRG,
set BCLIF
TBRG
SDA
SDA asserted low
SCL
PEN
BCLIF
P
‘ 0’
SSPIF
‘ 0’
FIGURE 13-27:
BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG
TBRG
TBRG
SDA
Assert SDA
SCL
SCL goes low before SDA goes high,
set BCLIF
PEN
BCLIF
P
‘ 0’
SSPIF
‘ 0’
© 2009 Microchip Technology Inc.
DS41291F-page 207
PIC16F882/883/884/886/887
13.4.17
SSP MASK REGISTER
2
An SSP Mask (SSPMSK) register is available in I C
Slave mode as a mask for the value held in the
SSPSR register during an address comparison
operation. A zero (‘0’) bit in the SSPMSK register has
the effect of making the corresponding bit in the
SSPSR register a “don’t care”.
This register is reset to all ‘1’s upon any Reset
condition and, therefore, has no effect on standard
SSP operation until written with a mask value.
REGISTER 13-4:
This register must be initiated prior to setting
SSPM<3:0> bits to select the I2C Slave mode (7-bit or
10-bit address).
This register can only be accessed when the appropriate
mode is selected by bits (SSPM<3:0> of SSPCON).
The SSP 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 SSP mask has no effect during the
reception of the first (high) byte of the address.
SSPMSK: SSP MASK 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
MSK7
MSK6
MSK5
MSK4
MSK3
MSK2
MSK1
MSK0(2)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-1
MSK<7:1>: Mask bits
1 = The received address bit n is compared to SSPADD<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(2)
I2C Slave mode, 10-bit Address (SSPM<3:0> = 0111):
1 = The received address bit 0 is compared to SSPADD<0> to detect I2C address match
0 = The received address bit 0 is not used to detect I2C address match
Note 1: When SSPCON bits SSPM<3:0> = 1001, any reads or writes to the SSPADD SFR address are accessed
through the SSPMSK register.
2: In all other SSP modes, this bit has no effect.
DS41291F-page 208
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
14.0
SPECIAL FEATURES OF THE
CPU
The PIC16F882/883/884/886/887 have a host of features intended to maximize system reliability, minimize
cost through elimination of external components, provide power-saving features and offer code protection.
These features are:
• Reset
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• Oscillator selection
• Sleep
• Code protection
• ID Locations
• In-Circuit Serial Programming™
• Low-voltage In-Circuit Serial Programming™
The PIC16F882/883/884/886/887 have two timers that
offer necessary delays on power-up. One is the
Oscillator Start-up Timer (OST), intended to keep the
chip in Reset until the crystal oscillator is stable. The
other is the Power-up Timer (PWRT), which provides a
fixed delay of 64 ms (nominal) on power-up only,
designed to keep the part in Reset while the power
supply stabilizes. There is also circuitry to reset the
device if a brown-out occurs, which can use the
Power-up Timer to provide at least a 64 ms Reset. With
these three functions-on-chip, most applications need
no external Reset circuitry.
The Sleep mode is designed to offer a very low-current
Power-Down mode. The user can wake-up from Sleep
through:
• External Reset
• Watchdog Timer Wake-up
• An interrupt
Several oscillator options are also made available to
allow the part to fit the application. The INTOSC option
saves system cost while the LP crystal option saves
power. A set of Configuration bits are used to select
various options (see Register 14-3).
© 2009 Microchip Technology Inc.
DS41291F-page 209
PIC16F882/883/884/886/887
14.1
Configuration Bits
The Configuration bits can be programmed (read as
‘0’), or left unprogrammed (read as ‘1’) to select various
device configurations as shown in Register 14-1.
These bits are mapped in program memory location
2007h and 2008h, respectively.
REGISTER 14-1:
—
Note:
Address 2007h and 2008h are beyond the
user program memory space. It belongs to
the special configuration memory space
(2000h-3FFFh), which can be accessed
only during programming. See “PIC16F88X
Memory
Programming
Specification”
(DS41287) for more information.
CONFIG1: CONFIGURATION WORD REGISTER 1
—
DEBUG
LVP
FCMEN
IESO
BOREN1
BOREN0
bit 15
bit 8
CPD
CP
MCLRE
PWRTE
WDTE
FOSC2
FOSC1
bit 7
bit 0
bit 15-14
Unimplemented: Read as ‘1’
bit 13
DEBUG: In-Circuit Debugger Mode bit
1 = In-Circuit Debugger disabled, RB6/ICSPCLK and RB7/ICSPDAT are general purpose I/O pins
0 = In-Circuit Debugger enabled, RB6/ICSPCLK and RB7/ICSPDAT are dedicated to the debugger
bit 12
LVP: Low Voltage Programming Enable bit
1 = RB3/PGM pin has PGM function, low voltage programming enabled
0 = RB3 pin is digital I/O, HV on MCLR must be used for programming
bit 11
FCMEN: Fail-Safe Clock Monitor Enabled bit
1 = Fail-Safe Clock Monitor is enabled
0 = Fail-Safe Clock Monitor is disabled
bit 10
IESO: Internal External Switchover bit
1 = Internal/External Switchover mode is enabled
0 = Internal/External Switchover mode is disabled
bit 9-8
BOREN<1:0>: Brown-out Reset Selection bits(1)
11 = BOR enabled
10 = BOR enabled during operation and disabled in Sleep
01 = BOR controlled by SBOREN bit of the PCON register
00 = BOR disabled
bit 7
CPD: Data Code Protection bit(2)
1 = Data memory code protection is disabled
0 = Data memory code protection is enabled
bit 6
CP: Code Protection bit(3)
1 = Program memory code protection is disabled
0 = Program memory code protection is enabled
bit 5
MCLRE: RE3/MCLR pin function select bit(4)
1 = RE3/MCLR pin function is MCLR
0 = RE3/MCLR pin function is digital input, MCLR internally tied to VDD
bit 4
PWRTE: Power-up Timer Enable bit
1 = PWRT disabled
0 = PWRT enabled
bit 3
WDTE: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled and can be enabled by SWDTEN bit of the WDTCON register
bit 2-0
FOSC<2:0>: Oscillator Selection bits
111 = RC oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, RC on RA7/OSC1/CLKIN
110 = RCIO oscillator: I/O function on RA6/OSC2/CLKOUT pin, RC on RA7/OSC1/CLKIN
101 = INTOSC oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN
100 = INTOSCIO oscillator: I/O function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN
011 = EC: I/O function on RA6/OSC2/CLKOUT pin, CLKIN on RA7/OSC1/CLKIN
010 = HS oscillator: High-speed crystal/resonator on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
001 = XT oscillator: Crystal/resonator on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
000 = LP oscillator: Low-power crystal on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN
Note
FOSC0
1:
2:
3:
4:
Enabling Brown-out Reset does not automatically enable Power-up Timer.
The entire data EEPROM will be erased when the code protection is turned off.
The entire program memory will be erased when the code protection is turned off.
When MCLR is asserted in INTOSC or RC mode, the internal clock oscillator is disabled.
DS41291F-page 210
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 14-2:
—
CONFIG2: CONFIGURATION WORD REGISTER 2
—
—
—
—
WRT1
WRT0
BOR4V
bit 15
bit 8
—
—
—
—
—
—
—
—
bit 7
bit 0
bit 15-11
Unimplemented: Read as ‘1’
bit 10-9
WRT<1:0>: Flash Program Memory Self Write Enable bits
PIC16F883/PIC16F884
00 = 0000h to 07FFh write protected, 0800h to 0FFFh may be modified by EECON control
01 = 0000h to 03FFh write protected, 0400h to 0FFFh may be modified by EECON control
10 = 0000h to 00FFh write protected, 0100h to 0FFFh may be modified by EECON control
11 = Write protection off
PIC16F886/PIC16F887
00 = 0000h to 0FFFh write protected, 1000h to 1FFFh may be modified by EECON control
01 = 0000h to 07FFh write protected, 0800h to 1FFFh may be modified by EECON control
10 = 0000h to 00FFh write protected, 0100h to 1FFFh may be modified by EECON control
11 = Write protection off
PIC16F882
00 = 0000h to 03FFh write protected, 0400h to 07FFh may be modified by EECON control
01 = 0000h to 00FFh write protected, 0100h to 07FFh may be modified by EECON control
11 = Write protection off
bit 8
BOR4V: Brown-out Reset Selection bit
0 = Brown-out Reset set to 2.1V
1 = Brown-out Reset set to 4.0V
bit 7-0
Unimplemented: Read as ‘1’
© 2009 Microchip Technology Inc.
DS41291F-page 211
PIC16F882/883/884/886/887
14.2
Reset
The
PIC16F882/883/884/886/887
between various kinds of Reset:
a)
b)
c)
d)
e)
f)
differentiates
Power-on Reset (POR)
WDT Reset during normal operation
WDT Reset during Sleep
MCLR Reset during normal operation
MCLR Reset during Sleep
Brown-out Reset (BOR)
Some registers are not affected in any Reset condition;
their status is unknown on POR and unchanged in any
other Reset. Most other registers are reset to a “Reset
state” on:
•
•
•
•
•
They are not affected by a WDT Wake-up since this is
viewed as the resumption of normal operation. TO and
PD bits are set or cleared differently in different Reset
situations, as indicated in Table 14-2. These bits are
used in software to determine the nature of the Reset.
See Table 14-5 for a full description of Reset states of
all registers.
A simplified block diagram of the On-Chip Reset Circuit
is shown in Figure 14-1.
The MCLR Reset path has a noise filter to detect and
ignore small pulses. See Section 17.0 “Electrical
Specifications” for pulse-width specifications.
Power-on Reset
MCLR Reset
MCLR Reset during Sleep
WDT Reset
Brown-out Reset (BOR)
FIGURE 14-1:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External
Reset
MCLR/VPP pin
Sleep
WDT
Module
WDT
Time-out
Reset
VDD Rise
Detect
Power-on Reset
VDD
Brown-out(1)
Reset
BOREN
SBOREN
S
OST/PWRT
OST
Chip_Reset
10-bit Ripple Counter
R
Q
OSC1/
CLKI pin
PWRT
LFINTOSC
11-bit Ripple Counter
Enable PWRT
Enable OST
Note
1:
Refer to the Configuration Word Register 1 (Register 14-1).
DS41291F-page 212
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
14.2.1
POWER-ON RESET (POR)
FIGURE 14-2:
The on-chip POR circuit holds the chip in Reset until VDD
has reached a high enough level for proper operation. A
maximum rise time for VDD is required. See
Section 17.0 “Electrical Specifications” for details. If
the BOR is enabled, the maximum rise time specification
does not apply. The BOR circuitry will keep the device in
Reset until VDD reaches VBOR (see Section 14.2.4
“Brown-out Reset (BOR)”).
Note:
VDD
PIC16F886
R1
1 kΩ (or greater)
MCLR
The POR circuit does not produce an
internal Reset when VDD declines. To
re-enable the POR, VDD must reach Vss
for a minimum of 100 μs.
When the device starts normal operation (exits the
Reset condition), device operating parameters (i.e.,
voltage, frequency, temperature, etc.) must be met to
ensure operation. If these conditions are not met, the
device must be held in Reset until the operating
conditions are met.
RECOMMENDED MCLR
CIRCUIT
C1
0.1 μF
(optional, not critical)
14.2.3
POWER-UP TIMER (PWRT)
PIC16F882/883/884/886/887 has a noise filter in the
MCLR Reset path. The filter will detect and ignore
small pulses.
The Power-up Timer provides a fixed 64 ms (nominal)
time-out on power-up only, from POR or Brown-out
Reset. The Power-up Timer operates from the 31 kHz
LFINTOSC oscillator. For more information, see
Section 4.5 “Internal Clock Modes”. The chip is kept
in Reset as long as PWRT is active. The PWRT delay
allows the VDD to rise to an acceptable level. A
Configuration bit, PWRTE, can disable (if set) or enable
(if cleared or programmed) the Power-up Timer. The
Power-up Timer should be enabled when Brown-out
Reset is enabled, although it is not required.
It should be noted that a WDT Reset does not drive
MCLR pin low.
The Power-up Timer delay will vary from chip-to-chip
and vary due to:
The behavior of the ESD protection on the MCLR pin
has been altered from early devices of this family.
Voltages applied to the pin that exceed its specification
can result in both MCLR Resets and excessive current
beyond the device specification during the ESD event.
For this reason, Microchip recommends that the MCLR
pin no longer be tied directly to VDD. The use of an RC
network, as shown in Figure 14-2, is suggested.
• VDD variation
• Temperature variation
• Process variation
For additional information, refer to Application Note
AN607, “Power-up Trouble Shooting” (DS00607).
14.2.2
MCLR
See DC parameters for details (Section 17.0 “Electrical
Specifications”).
An internal MCLR option is enabled by clearing the
MCLRE bit in the Configuration Word Register 1. When
MCLRE = 0, the Reset signal to the chip is generated
internally. When the MCLRE = 1, the RA3/MCLR pin
becomes an external Reset input. In this mode, the
RA3/MCLR pin has a weak pull-up to VDD.
© 2009 Microchip Technology Inc.
DS41291F-page 213
PIC16F882/883/884/886/887
14.2.4
BROWN-OUT RESET (BOR)
occur regardless of VDD slew rate. A Reset is not insured
to occur if VDD falls below VBOR for less than parameter
(TBOR).
The BOREN0 and BOREN1 bits in the Configuration
Word Register 1 select one of four BOR modes. Two
modes have been added to allow software or hardware
control of the BOR enable. When BOREN<1:0> = 01,
the SBOREN bit (PCON<4>) enables/disables the
BOR allowing it to be controlled in software. By
selecting BOREN<1:0>, the BOR is automatically
disabled in Sleep to conserve power and enabled on
wake-up. In this mode, the SBOREN bit is disabled.
See Register 14-3 for the Configuration Word
definition.
On any Reset (Power-on, Brown-out Reset, Watchdog
Timer, etc.), the chip will remain in Reset until VDD rises
above VBOR (see Figure 14-3). The Power-up Timer
will now be invoked, if enabled and will keep the chip in
Reset an additional 64 ms.
Note:
The Power-up Timer is enabled by the
PWRTE bit in the Configuration Word
Register 1.
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 re-initialized. Once VDD
rises above VBOR, the Power-up Timer will execute a
64 ms Reset.
The BOR4V bit in the Configuration Word Register 2
selects one of two Brown-out Reset voltages. When
BOR4B = 1, VBOR is set to 4V. When BOR4V = 0, VBOR
is set to 2.1V.
If VDD falls below VBOR for greater than parameter
(TBOR) (see Section 17.0 “Electrical Specifications”),
the Brown-out situation will reset the device. This will
FIGURE 14-3:
BROWN-OUT SITUATIONS
VDD
Internal
Reset
VBOR
64 ms(1)
VDD
Internal
Reset
VBOR
< 64 ms
64 ms(1)
VDD
Internal
Reset
Note 1:
VBOR
64 ms(1)
64 ms delay only if PWRTE bit is programmed to ‘0’.
DS41291F-page 214
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
14.2.5
TIME-OUT SEQUENCE
14.2.6
On power-up, the time-out sequence is as follows: first,
PWRT time-out is invoked after POR has expired, then
OST is activated after the PWRT time-out has expired.
The total time-out will vary based on oscillator
configuration and PWRTE bit status. For example, in
EC mode with PWRTE bit erased (PWRT disabled),
there will be no time-out at all. Figures 14-4, 14-5
and 14-6 depict time-out sequences. The device can
execute code from the INTOSC while OST is active by
enabling Two-Speed Start-up or Fail-Safe Monitor (see
Section 4.7.2 “Two-speed Start-up Sequence” and
Section 4.8 “Fail-Safe Clock Monitor”).
The Power Control register PCON (address 8Eh) has
two Status bits to indicate what type of Reset that last
occurred.
Bit 0 is BOR (Brown-out Reset). BOR is unknown on
Power-on Reset. It must then be set by the user and
checked on subsequent Resets to see if BOR = 0,
indicating that a Brown-out has occurred. The BOR
Status bit is a “don’t care” and is not necessarily
predictable if the brown-out circuit is disabled
(BOREN<1:0> = 00 in the Configuration Word
Register 1).
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire. Then,
bringing MCLR high will begin execution immediately
(see Figure 14-5). This is useful for testing purposes or
to
synchronize
more
than
one
PIC16F882/883/884/886/887 device operating in parallel.
Bit 1 is POR (Power-on Reset). It is a ‘0’ on Power-on
Reset and unaffected otherwise. The user must write a
‘1’ to this bit following a Power-on Reset. On a
subsequent Reset, if POR is ‘0’, it will indicate that a
Power-on Reset has occurred (i.e., VDD may have
gone too low).
For more information, see Section 3.2.2 “Ultra
Low-Power
Wake-up”
and
Section 14.2.4
“Brown-out Reset (BOR)”.
Table 14-5 shows the Reset conditions for some
special registers, while Table 14-4 shows the Reset
conditions for all the registers.
TABLE 14-1:
POWER CONTROL (PCON)
REGISTER
TIME-OUT IN VARIOUS SITUATIONS
Power-up
Brown-out Reset
PWRTE = 0
PWRTE = 1
PWRTE = 0
PWRTE = 1
Wake-up from
Sleep
TPWRT +
1024 • TOSC
1024 • TOSC
TPWRT +
1024 • TOSC
1024 • TOSC
1024 • TOSC
LP, T1OSCIN = 1
TPWRT
—
TPWRT
—
—
RC, EC, INTOSC
TPWRT
—
TPWRT
—
—
Oscillator Configuration
XT, HS, LP
TABLE 14-2:
STATUS/PCON BITS AND THEIR SIGNIFICANCE
POR
BOR
TO
PD
Condition
0
x
1
1
Power-on Reset
u
0
1
1
Brown-out Reset
u
u
0
u
WDT Reset
u
u
0
0
WDT Wake-up
u
u
u
u
MCLR Reset during normal operation
u
u
1
0
MCLR Reset during Sleep
Legend: u = unchanged, x = unknown
TABLE 14-3:
Name
PCON
STATUS
Legend:
Note 1:
SUMMARY OF REGISTERS ASSOCIATED WITH BROWN-OUT
Bit 7
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
SBOREN
—
—
POR
BOR
--01 --qq
--0u --uu
TO
PD
Z
DC
C
0001 1xxx
000q quuu
Bit 6
Bit 5
Bit 4
—
—
ULPWUE
IRP
RP1
RPO
u = unchanged, x = unknown, — = unimplemented bit, reads as ‘0’, q = value depends on condition. Shaded cells are not used by BOR.
Other (non Power-up) Resets include MCLR Reset and Watchdog Timer Reset during normal operation.
© 2009 Microchip Technology Inc.
DS41291F-page 215
PIC16F882/883/884/886/887
FIGURE 14-4:
TIME-OUT SEQUENCE ON POWER-UP (DELAYED MCLR): CASE 1
VDD
MCLR
Internal POR
TPWRT
PWRT Time-out
TOST
OST Time-out
Internal Reset
TIME-OUT SEQUENCE ON POWER-UP (DELAYED MCLR): CASE 2
FIGURE 14-5:
VDD
MCLR
Internal POR
TPWRT
PWRT Time-out
TOST
OST Time-out
Internal Reset
FIGURE 14-6:
TIME-OUT SEQUENCE ON POWER-UP (MCLR WITH VDD)
VDD
MCLR
Internal POR
TPWRT
PWRT Time-out
TOST
OST Time-out
Internal Reset
DS41291F-page 216
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 14-4:
Register
W
INDF
TMR0
INITIALIZATION CONDITION FOR REGISTER
Address
Power-on
Reset
MCLR Reset
WDT Reset
Brown-out Reset(1)
Wake-up from Sleep through
Interrupt
Wake-up from Sleep through
WDT Time-out
—
xxxx xxxx
uuuu uuuu
uuuu uuuu
00h/80h/10
0h/180h
xxxx xxxx
xxxx xxxx
uuuu uuuu
01h/101h
xxxx xxxx
uuuu uuuu
uuuu uuuu
PCL
02h/82h/10
2h/182h
0000 0000
0000 0000
PC + 1(3)
STATUS
03h/83h/10
3h/183h
0001 1xxx
000q quuu(4)
uuuq quuu(4)
FSR
04h/84h/10
4h/184h
xxxx xxxx
uuuu uuuu
uuuu uuuu
PORTA
05h
xxxx xxxx
0000 0000
uuuu uuuu
PORTB
06h/106h
xxxx xxxx
0000 0000
uuuu uuuu
PORTC
07h
xxxx xxxx
0000 0000
uuuu uuuu
PORTD
08h
xxxx xxxx
0000 0000
uuuu uuuu
PORTE
09h
---- xxxx
---- 0000
---- uuuu
PCLATH
0Ah/8Ah/10
Ah/18Ah
---0 0000
---0 0000
---u uuuu
INTCON
0Bh/8Bh/10
Bh/18Bh
0000 000x
0000 000u
uuuu uuuu(2)
PIR1
0Ch
0000 0000
0000 0000
uuuu uuuu(2)
PIR2
0Dh
0000 0000
0000 0000
uuuu uuuu(2)
TMR1L
0Eh
xxxx xxxx
uuuu uuuu
uuuu uuuu
TMR1H
0Fh
xxxx xxxx
uuuu uuuu
uuuu uuuu
T1CON
10h
0000 0000
uuuu uuuu
-uuu uuuu
TMR2
11h
0000 0000
0000 0000
uuuu uuuu
T2CON
12h
-000 0000
-000 0000
-uuu uuuu
SSPBUF
13h
xxxx xxxx
uuuu uuuu
uuuu uuuu
SSPCON
14h
0000 0000
0000 0000
uuuu uuuu
CCPR1L
15h
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR1H
16h
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP1CON
17h
0000 0000
0000 0000
uuuu uuuu
RCSTA
18h
0000 000x
0000 0000
uuuu uuuu
TXREG
19h
0000 0000
0000 0000
uuuu uuuu
RCREG
1Ah
0000 0000
0000 0000
uuuu uuuu
1Bh
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCPR2L
Legend:
Note 1:
2:
3:
4:
5:
6:
u = unchanged, x = unknown, – = unimplemented bit, reads as ‘0’, q = value depends on condition.
If VDD goes too low, Power-on Reset will be activated and registers will be affected differently.
One or more bits in INTCON and/or PIR1 will be affected (to cause wake-up).
When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt
vector (0004h).
See Table 14-5 for Reset value for specific condition.
If Reset was due to brown-out, then bit 0 = 0. All other Resets will cause bit 0 = u.
Accessible only when SSPCON register bits SSPM<3:0> = 1001.
© 2009 Microchip Technology Inc.
DS41291F-page 217
PIC16F882/883/884/886/887
TABLE 14-4:
INITIALIZATION CONDITION FOR REGISTER (CONTINUED)
Address
Power-on
Reset
MCLR Reset
WDT Reset (Continued)
Brown-out Reset(1)
Wake-up from Sleep through
Interrupt
Wake-up from Sleep through
WDT Time-out (Continued)
CCPR2H
1Ch
xxxx xxxx
uuuu uuuu
uuuu uuuu
CCP2CON
1Dh
--00 0000
--00 0000
--uu uuuu
ADRESH
1Eh
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADCON0
1Fh
00-0 0000
00-0 0000
uu-u uuuu
Register
OPTION_REG
81h/181h
1111 1111
1111 1111
uuuu uuuu
TRISA
85h
1111 1111
1111 1111
uuuu uuuu
TRISB
86h/186h
1111 1111
1111 1111
uuuu uuuu
TRISC
87h
1111 1111
1111 1111
uuuu uuuu
TRISD
88h
1111 1111
1111 1111
uuuu uuuu
TRISE
89h
---- 1111
---- 1111
---- uuuu
PIE1
8Ch
0000 0000
0000 0000
uuuu uuuu
PIE2
8Dh
0000 0000
0000 0000
uuuu uuuu
(1, 5)
PCON
8Eh
--01 --0x
--0u --uu
OSCCON
8Fh
-110 q000
-110 q000
OSCTUNE
90h
---0 0000
---u uuuu
---u uuuu
SSPCON2
91h
0000 0000
0000 0000
uuuu uuuu
PR2
92h
1111 1111
1111 1111
1111 1111
SSPADD(6)
93h
0000 0000
0000 0000
uuuu uuuu
SSPMSK(6)
93h
1111 1111
1111 1111
1111 1111
SSPSTAT
94h
0000 0000
0000 0000
uuuu uuuu
WPUB
95h
1111 1111
1111 1111
uuuu uuuu
IOCB
96h
0000 0000
0000 0000
uuuu uuuu
VRCON
97h
0000 0000
0000 0000
uuuu uuuu
TXSTA
98h
0000 -010
0000 -010
uuuu -uuu
SPBRG
99h
0000 0000
0000 0000
uuuu uuuu
SPBRGH
9Ah
0000 0000
0000 0000
uuuu uuuu
PWM1CON
9Bh
0000 0000
0000 0000
uuuu uuuu
ECCPAS
9Ch
0000 0000
0000 0000
uuuu uuuu
PSTRCON
9Dh
---0 0001
---0 0001
---u uuuu
ADRESL
9Eh
xxxx xxxx
uuuu uuuu
uuuu uuuu
ADCON1
9Fh
0-00 ----
0-00 ----
u-uu ----
WDTCON
105h
---0 1000
---0 1000
---u uuuu
CM1CON0
107h
0000 0-00
0000 0-00
uuuu u-uu
CM2CON0
108h
0000 0-00
0000 0-00
uuuu u-uu
Legend:
Note 1:
2:
3:
4:
5:
6:
--uu --uu
-uuu uuuu
u = unchanged, x = unknown, – = unimplemented bit, reads as ‘0’, q = value depends on condition.
If VDD goes too low, Power-on Reset will be activated and registers will be affected differently.
One or more bits in INTCON and/or PIR1 will be affected (to cause wake-up).
When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt
vector (0004h).
See Table 14-5 for Reset value for specific condition.
If Reset was due to brown-out, then bit 0 = 0. All other Resets will cause bit 0 = u.
Accessible only when SSPCON register bits SSPM<3:0> = 1001.
DS41291F-page 218
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 14-4:
INITIALIZATION CONDITION FOR REGISTER (CONTINUED)
Address
Power-on
Reset
MCLR Reset
WDT Reset (Continued)
Brown-out Reset(1)
Wake-up from Sleep through
Interrupt
Wake-up from Sleep through
WDT Time-out (Continued)
CM2CON1
109h
0000 0--0
0000 0--0
uuuu u--u
EEDAT
10Ch
0000 0000
0000 0000
uuuu uuuu
EEADR
10Dh
0000 0000
0000 0000
uuuu uuuu
EEDATH
10Eh
--00 0000
--00 0000
--uu uuuu
EEADRH
10Fh
---0 0000
---0 0000
---u uuuu
SRCON
185h
0000 00-0
0000 00-0
uuuu uu-u
BAUDCTL
187h
01-0 0-00
01-0 0-00
uu-u u-uu
ANSEL
188h
1111 1111
1111 1111
uuuu uuuu
ANSELH
189h
1111 1111
1111 1111
uuuu uuuu
EECON1
18Ch
---- x000
---- q000
---- uuuu
18Dh
---- ----
---- ----
---- ----
Register
EECON2
Legend:
Note 1:
2:
3:
4:
5:
6:
u = unchanged, x = unknown, – = unimplemented bit, reads as ‘0’, q = value depends on condition.
If VDD goes too low, Power-on Reset will be activated and registers will be affected differently.
One or more bits in INTCON and/or PIR1 will be affected (to cause wake-up).
When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt
vector (0004h).
See Table 14-5 for Reset value for specific condition.
If Reset was due to brown-out, then bit 0 = 0. All other Resets will cause bit 0 = u.
Accessible only when SSPCON register bits SSPM<3:0> = 1001.
TABLE 14-5:
INITIALIZATION CONDITION FOR SPECIAL REGISTERS
Program
Counter
Status
Register
PCON
Register
Power-on Reset
000h
0001 1xxx
--01 --0x
MCLR Reset during normal operation
000h
000u uuuu
--0u --uu
MCLR Reset during Sleep
000h
0001 0uuu
--0u --uu
000h
0000 uuuu
--0u --uu
PC + 1
uuu0 0uuu
--uu --uu
Condition
WDT Reset
WDT Wake-up
Brown-out Reset
Interrupt Wake-up from Sleep
000h
0001 1uuu
--01 --u0
PC + 1(1)
uuu1 0uuu
--uu --uu
Legend: u = unchanged, x = unknown, — = unimplemented bit, reads as ‘0’.
Note 1: When the wake-up is due to an interrupt and Global Interrupt Enable bit, GIE, is set, the PC is loaded with
the interrupt vector (0004h) after execution of PC + 1.
© 2009 Microchip Technology Inc.
DS41291F-page 219
PIC16F882/883/884/886/887
14.3
Interrupts
The PIC16F882/883/884/886/887
interrupt sources:
•
•
•
•
•
•
•
•
•
•
•
•
•
has
multiple
External Interrupt RB0/INT
Timer0 Overflow Interrupt
PORTB Change Interrupts
2 Comparator Interrupts
A/D Interrupt
Timer1 Overflow Interrupt
Timer2 Match Interrupt
EEPROM Data Write Interrupt
Fail-Safe Clock Monitor Interrupt
Enhanced CCP Interrupt
EUSART Receive and Transmit Interrupts
Ultra Low-Power Wake-up Interrupt
MSSP Interrupt
The Interrupt Control register (INTCON) and Peripheral
Interrupt Request Register 1 (PIR1) record individual
interrupt requests in flag bits. The INTCON register
also has individual and global interrupt enable bits.
A Global Interrupt Enable bit, GIE (INTCON<7>),
enables (if set) all unmasked interrupts, or disables (if
cleared) all interrupts. Individual interrupts can be
disabled through their corresponding enable bits in the
INTCON, PIE1 and PIE2 registers, respectively. GIE is
cleared on Reset.
The following interrupt flags are contained in the PIR2
register:
•
•
•
•
•
Fail-Safe Clock Monitor Interrupt
2 Comparator Interrupts
EEPROM Data Write Interrupt
Ultra Low-Power Wake-up Interrupt
CCP2 Interrupt
When an interrupt is serviced:
• The GIE is cleared to disable any further interrupt.
• The return address is pushed onto the stack.
• The PC is loaded with 0004h.
For external interrupt events, such as the INT pin,
PORTB change interrupts, the interrupt latency will be
three or four instruction cycles. The exact latency
depends upon when the interrupt event occurs (see
Figure 14-8). The latency is the same for one or
two-cycle instructions. Once in the Interrupt Service
Routine, the source(s) of the interrupt can be
determined by polling the interrupt flag bits. The
interrupt flag bit(s) must be cleared in software before
re-enabling interrupts to avoid multiple interrupt
requests.
Note 1: Individual interrupt flag bits are set,
regardless of the status of their
corresponding mask bit or the GIE bit.
2: When an instruction that clears the GIE
bit is executed, any interrupts that were
pending for execution in the next cycle
are ignored. The interrupts, which were
ignored, are still pending to be serviced
when the GIE bit is set again.
The Return from Interrupt instruction, RETFIE, exits
the interrupt routine, as well as sets the GIE bit, which
re-enables unmasked interrupts.
The following interrupt flags are contained in the INTCON register:
• INT Pin Interrupt
• PORTB Change Interrupts
• Timer0 Overflow Interrupt
The peripheral interrupt flags are contained in the PIR1
and PIR2 registers. The corresponding interrupt enable
bits are contained in PIE1 and PIE2 registers.
The following interrupt flags are contained in the PIR1
register:
•
•
•
•
•
•
•
A/D Interrupt
EUSART Receive and Transmit Interrupts
Timer1 Overflow Interrupt
Synchronous Serial Port (SSP) Interrupt
Enhanced CCP1 Interrupt
Timer1 Overflow Interrupt
Timer2 Match Interrupt
DS41291F-page 220
For additional information on Timer1, Timer2,
comparators, A/D, data EEPROM, EUSART, MSSP or
Enhanced CCP modules, refer to the respective
peripheral section.
14.3.1
RB0/INT INTERRUPT
External interrupt on RB0/INT pin is edge-triggered;
either rising if the INTEDG bit (OPTION_REG<6>) is
set, or falling, if the INTEDG bit is clear. When a valid
edge appears on the RB0/INT pin, the INTF bit
(INTCON<1>) is set. This interrupt can be disabled by
clearing the INTE control bit (INTCON<4>). The INTF
bit must be cleared in software in the Interrupt Service
Routine before re-enabling this interrupt. The RB0/INT
interrupt can wake-up the processor from Sleep, if the
INTE bit was set prior to going into Sleep. The status of
the GIE bit decides whether or not the processor
branches to the interrupt vector following wake-up
(0004h). See Section 14.6 “Power-Down Mode
(Sleep)” for details on Sleep and Figure 14-10 for
timing of wake-up from Sleep through RB0/INT
interrupt.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
14.3.2
TIMER0 INTERRUPT
14.3.3
An overflow (FFh → 00h) in the TMR0 register will set
the T0IF (INTCON<2>) bit. The interrupt can be
enabled/disabled by setting/clearing T0IE (INTCON<5>)
bit. See Section 5.0 “Timer0 Module” for operation of
the Timer0 module.
An input change on PORTB change sets the RBIF
(INTCON<0>)
bit.
The
interrupt
can
be
enabled/disabled by setting/clearing the RBIE
(INTCON<3>) bit. Plus, individual pins can be
configured through the IOCB register.
Note:
FIGURE 14-7:
PORTB INTERRUPT
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. See
Section 3.4.3 “Interrupt-on-Change” for
more information.
INTERRUPT LOGIC
IOC-RB0
IOCB0
IOC-RB1
IOCB1
IOC-RB2
IOCB2
BCLIF
BCLIE
IOC-RB3
IOCB3
SSPIF
SSPIE
IOC-RB4
IOCB4
TXIF
TXIE
IOC-RB5
IOCB5
RCIF
RCIE
IOC-RB6
IOCB6
TMR2IF
TMR2IE
IOC-RB7
IOCB7
TMR1IF
TMR1IE
C1IF
C1IE
C2IF
C2IE
Wake-up (If in Sleep mode)(1)
T0IF
T0IE
Interrupt to CPU
INTF
INTE
RBIF
RBIE
PEIE
GIE
ADIF
ADIE
EEIF
EEIE
Note 1:
OSFIF
OSFIE
CCP1IF
CCP1IE
Some peripherals depend upon the
system clock for operation. Since the
system clock is suspended during
Sleep, these peripherals will not wake
the part from Sleep. See Section 14.6.1
“Wake-up from Sleep”.
CCP2IF
CCP2IE
ULPWUIF
ULPWUIE
© 2009 Microchip Technology Inc.
DS41291F-page 221
PIC16F882/883/884/886/887
FIGURE 14-8:
INT PIN INTERRUPT TIMING
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
OSC1
CLKOUT (3)
(4)
INT pin
(1)
(1)
INTF flag
(INTCON<1>)
Interrupt Latency (2)
(5)
GIE bit
(INTCON<7>)
INSTRUCTION FLOW
PC
Instruction
Fetched
INTCON
Inst (0004h)
Inst (0005h)
Dummy Cycle
Inst (0004h)
—
Dummy Cycle
Inst (PC)
0005h
INTF flag is sampled here (every Q1).
2:
Asynchronous interrupt latency = 3-4 TCY. Synchronous latency = 3 TCY, where TCY = instruction cycle time. Latency
is the same whether Inst (PC) is a single cycle or a 2-cycle instruction.
3:
CLKOUT is available only in INTOSC and RC Oscillator modes.
4:
For minimum width of INT pulse, refer to AC specifications in Section 17.0 “Electrical Specifications”.
5:
INTF is enabled to be set any time during the Q4-Q1 cycles.
TABLE 14-6:
Name
Inst (PC + 1)
Inst (PC – 1)
0004h
PC + 1
PC + 1
Inst (PC)
Instruction
Executed
Note 1:
PC
SUMMARY OF INTERRUPT REGISTERS
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
GIE
PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
0000 000x
0000 000x
PIE1
—
ADIE
RCIE
TXIE
SSPIE
CCP1IE
TMR2IE
TMR1IE
-000 0000
-000 0000
PIE2
OSFIE
C2IE
C1IE
EEIE
BCLIE
ULPWUIE
—
CCP2IE
0000 00-0
0000 00-0
PIR1
—
ADIF
RCIF
TXIF
SSPIF
CCP1IF
TMR2IF
TMR1IF
-000 0000
-000 0000
OSFIF
C2IF
C1IF
EEIF
BCLIF
ULPWUIF
—
CCP2IF
0000 00-0
0000 00-0
PIR2
Legend:
x = unknown, u = unchanged, — = unimplemented read as ‘0’, q = value depends upon condition.
Shaded cells are not used by the Interrupt module.
DS41291F-page 222
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
14.4
Context Saving During Interrupts
During an interrupt, only the return PC value is saved
on the stack. Typically, users may wish to save key
registers during an interrupt (e.g., W and STATUS
registers). This must be implemented in software.
Since the upper 16 bytes of all GPR banks are common in the PIC16F882/883/884/886/887 (see
Figures 2-2 and 2-3), temporary holding registers,
W_TEMP and STATUS_TEMP, should be placed in
here. These 16 locations do not require banking and
therefore, make it easier to context save and restore.
The same code shown in Example 14-1 can be used
to:
•
•
•
•
•
Store the W register
Store the STATUS register
Execute the ISR code
Restore the Status (and Bank Select Bit register)
Restore the W register
Note:
The PIC16F882/883/884/886/887 normally does not require saving the
PCLATH. However, if computed GOTO’s
are used in the ISR and the main code, the
PCLATH must be saved and restored in
the ISR.
EXAMPLE 14-1:
MOVWF
SWAPF
SAVING STATUS AND W REGISTERS IN RAM
W_TEMP
STATUS,W
MOVWF STATUS_TEMP
:
:(ISR)
:
SWAPF STATUS_TEMP,W
MOVWF
SWAPF
SWAPF
STATUS
W_TEMP,F
W_TEMP,W
© 2009 Microchip Technology Inc.
;Copy W to TEMP
;Swap status to
;Swaps are used
;Save status to
register
be saved into W
because they do not affect the status bits
bank zero STATUS_TEMP register
;Insert user code here
;Swap STATUS_TEMP register into W
;(sets bank to original state)
;Move W into STATUS register
;Swap W_TEMP
;Swap W_TEMP into W
DS41291F-page 223
PIC16F882/883/884/886/887
14.5
14.5.2
Watchdog Timer (WDT)
The WDT has the following features:
•
•
•
•
•
Operates from the LFINTOSC (31 kHz)
Contains a 16-bit prescaler
Shares an 8-bit prescaler with Timer0
Time-out period is from 1 ms to 268 seconds
Configuration bit and software controlled
WDT is cleared under certain conditions described in
Table 14-7.
14.5.1
WDT OSCILLATOR
The WDT derives its time base from the 31 kHz
LFINTOSC. The LTS bit of the OSCCON register does
not reflect that the LFINTOSC is enabled.
WDT CONTROL
The WDTE bit is located in the Configuration Word
Register 1. When set, the WDT runs continuously.
When the WDTE bit in the Configuration Word
Register 1 is set, the SWDTEN bit of the WDTCON
register has no effect. If WDTE is clear, then the
SWDTEN bit can be used to enable and disable the
WDT. Setting the bit will enable it and clearing the bit
will disable it.
The PSA and PS<2:0> bits of the OPTION register
have the same function as in previous versions of the
PIC16F882/883/884/886/887 Family of microcontrollers. See Section 5.0 “Timer0 Module” for more
information.
The value of WDTCON is ‘---0 1000’ on all Resets.
This gives a nominal time base of 17 ms.
Note:
When the Oscillator Start-up Timer (OST)
is invoked, the WDT is held in Reset,
because the WDT Ripple Counter is used
by the OST to perform the oscillator delay
count. When the OST count has expired,
the WDT will begin counting (if enabled).
FIGURE 14-9:
WATCHDOG TIMER BLOCK DIAGRAM
From TMR0 Clock Source
0
Prescaler(1)
16-bit WDT Prescaler
1
8
PSA
31 kHz
LFINTOSC Clock
PS<2:0>
WDTPS<3:0>
0
1
PSA
WDTE from the Configuration Word Register 1
SWDTEN from WDTCON
WDT Time-out
Note
1:
TABLE 14-7:
This is the shared Timer0/WDT prescaler. See Section 5.1.3 “Software Programmable Prescaler” for more information.
WDT STATUS
Conditions
WDTE = 0
WDT
Cleared
CLRWDT Command
Oscillator Fail Detected
Exit Sleep + System Clock = T1OSC, EXTRC, INTOSC, EXTCLK
Exit Sleep + System Clock = XT, HS, LP
DS41291F-page 224
Cleared until the end of OST
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
REGISTER 14-3:
WDTCON: WATCHDOG TIMER CONTROL REGISTER
U-0
U-0
U-0
R/W-0
R/W-1
R/W-0
R/W-0
R/W-0
—
—
—
WDTPS3
WDTPS2
WDTPS1
WDTPS0
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 7-5
Unimplemented: Read as ‘0’
bit 4-1
WDTPS<3:0>: Watchdog Timer Period Select bits
Bit Value = Prescale Rate
0000 = 1:32
0001 = 1:64
0010 = 1:128
0011 = 1:256
0100 = 1:512 (Reset value)
0101 = 1:1024
0110 = 1:2048
0111 = 1:4096
1000 = 1:8192
1001 = 1:16384
1010 = 1:32768
1011 = 1:65536
1100 = reserved
1101 = reserved
1110 = reserved
1111 = reserved
bit 0
SWDTEN: Software Enable or Disable the Watchdog Timer(1)
1 = WDT is turned on
0 = WDT is turned off (Reset value)
x = Bit is unknown
Note 1: If WDTE Configuration bit = 1, then WDT is always enabled, irrespective of this control bit. If WDTE
Configuration bit = 0, then it is possible to turn WDT on/off with this control bit.
TABLE 14-8:
Name
Bit 7
CONFIG1(1)
OPTION_REG
WDTCON
Legend:
Note 1:
SUMMARY OF WATCHDOG TIMER REGISTER
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets
CPD
CP
MCLRE
PWRTE
WDTE
FOSC2
FOSC1
FOSC0
—
—
RBPU
INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
—
—
—
WDTPS3 WDTPS2 WSTPS1 WDTPS0 SWDTEN ---0 1000
---0 1000
Shaded cells are not used by the Watchdog Timer.
See Register 14-1 for operation of all Configuration Word Register 1 bits.
© 2009 Microchip Technology Inc.
DS41291F-page 225
PIC16F882/883/884/886/887
14.6
Power-Down Mode (Sleep)
The Power-down mode is entered by executing a
SLEEP instruction.
If the Watchdog Timer is enabled:
•
•
•
•
•
WDT will be cleared but keeps running.
PD bit in the STATUS register is cleared.
TO bit is set.
Oscillator driver is turned off.
I/O ports maintain the status they had before
SLEEP was executed (driving high, low or
high-impedance).
For lowest current consumption in this mode, all I/O pins
should be either at VDD or VSS, with no external circuitry
drawing current from the I/O pin and the comparators
and CVREF should be disabled. I/O pins that are
high-impedance inputs should be pulled high or low
externally to avoid switching currents caused by floating
inputs. The T0CKI input should also be at VDD or VSS for
lowest current consumption. The contribution from
on-chip pull-ups on PORTA should be considered.
The MCLR pin must be at a logic high level.
Note:
14.6.1
It should be noted that a Reset generated
by a WDT time-out does not drive MCLR
pin low.
WAKE-UP FROM SLEEP
The device can wake-up from Sleep through one of the
following events:
1.
2.
3.
External Reset input on MCLR pin.
Watchdog Timer Wake-up (if WDT was enabled).
Interrupt from RB0/INT pin, PORTB change or a
peripheral interrupt.
The first event will cause a device Reset. The two latter
events are considered a continuation of program execution. The TO and PD bits in the STATUS register can
be used to determine the cause of device Reset. The
PD bit, which is set on power-up, is cleared when Sleep
is invoked. TO bit is cleared if WDT Wake-up occurred.
The following peripheral interrupts can wake the device
from Sleep:
1.
2.
3.
4.
5.
6.
7.
8.
TMR1 interrupt. Timer1 must be operating as an
asynchronous counter.
ECCP Capture mode interrupt.
A/D conversion (when A/D clock source is FRC).
EEPROM write operation completion.
Comparator output changes state.
Interrupt-on-change.
External Interrupt from INT pin.
EUSART Break detect, I2C slave.
When the SLEEP instruction is being executed, the next
instruction (PC + 1) is prefetched. For the device to
wake-up through an interrupt event, the corresponding
interrupt enable bit must be set (enabled). Wake-up
occurs regardless of the state of the GIE bit. If the GIE
bit is clear (disabled), the device continues execution at
the instruction after the SLEEP instruction. If the GIE bit
is set (enabled), the device executes the instruction
after the SLEEP instruction, then branches to the interrupt address (0004h). In cases where the execution of
the instruction following SLEEP is not desirable, the
user should have a NOP after the SLEEP instruction.
Note:
If the global interrupts are disabled (GIE is
cleared), but any interrupt source has both
its interrupt enable bit and the corresponding
interrupt flag bits set, the device will
immediately wake-up from Sleep. The
SLEEP instruction is completely executed.
The WDT is cleared when the device wakes up from
Sleep, regardless of the source of wake-up.
14.6.2
WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and
any interrupt source has both its interrupt enable bit
and interrupt flag bit set, one of the following will occur:
• If the interrupt occurs before the execution of a
SLEEP instruction, the SLEEP instruction will
complete as a NOP. Therefore, the WDT and WDT
prescaler and postscaler (if enabled) will not be
cleared, the TO bit will not be set and the PD bit
will not be cleared.
• If the interrupt occurs during or after the execution of a SLEEP instruction, the device will immediately wake-up from Sleep. The SLEEP
instruction will be completely executed before the
wake-up. Therefore, the WDT and WDT prescaler
and postscaler (if enabled) will be cleared, the TO
bit will be set and the PD bit will be cleared.
Even if the flag bits were checked before executing a
SLEEP instruction, it may be possible for flag bits to
become set before the SLEEP instruction completes. To
determine whether a SLEEP instruction executed, test
the PD bit. If the PD bit is set, the SLEEP instruction
was executed as a NOP.
To ensure that the WDT is cleared, a CLRWDT instruction
should be executed before a SLEEP instruction.
Other peripherals cannot generate interrupts since
during Sleep, no on-chip clocks are present.
DS41291F-page 226
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 14-10:
WAKE-UP FROM SLEEP THROUGH INTERRUPT
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
TOST(2)
CLKOUT(4)
INT pin
INTF flag
(INTCON<1>)
Interrupt Latency (3)
GIE bit
(INTCON<7>)
Instruction Flow
PC
Instruction
Fetched
Instruction
Executed
Note
14.7
Processor in
Sleep
PC
Inst(PC) = Sleep
Inst(PC – 1)
PC + 1
PC + 2
Inst(PC + 1)
Inst(PC + 2)
Sleep
Inst(PC + 1)
14.8
Dummy Cycle
0004h
0005h
Inst(0004h)
Inst(0005h)
Dummy Cycle
Inst(0004h)
XT, HS or LP Oscillator mode assumed.
2:
TOST = 1024 TOSC (drawing not to scale). This delay does not apply to EC and RC Oscillator modes.
3:
GIE = 1 assumed. In this case after wake-up, the processor jumps to 0004h. If GIE = 0, execution will continue in-line.
4:
CLKOUT is not available in XT, HS, LP or EC Oscillator modes, but shown here for timing reference.
Code Protection
The entire data EEPROM and Flash
program memory will be erased when the
code protection is switched from on to off.
See the “PIC16F88X Memory Programming
Specification”
(DS41287)
for
more
information.
ID Locations
Four memory locations (2000h-2003h) are designated
as ID locations where the user can store checksum or
other code identification numbers. These locations are
not accessible during normal execution but are readable
and writable during Program/Verify mode. Only the
Least Significant 7 bits of the ID locations are used.
14.9
PC + 2
1:
If the code protection bit(s) have not been
programmed, the on-chip program memory can be
read out using ICSP™ for verification purposes.
Note:
PC + 2
The device is placed into a Program/Verify mode by
holding the RB6/ICSPCLK and RB7/ICSPDAT pins low,
while raising the MCLR (VPP) pin from VIL to VIHH. See
the “PIC16F88X Memory Programming Specification”
(DS41287) for more information. RB7 becomes the
programming data and RB6 becomes the programming
clock. Both RB7 and RB6 are Schmitt Trigger inputs in
this mode.
After Reset, to place the device into Program/Verify
mode, the Program Counter (PC) is at location 00h. A
6-bit command is then supplied to the device.
Depending on the command, 14 bits of program data
are then supplied to or from the device, depending on
whether the command was a Load or a Read. For
complete details of serial programming, please refer to
the “PIC16F88X Memory Programming Specification”
(DS41287).
A typical In-Circuit Serial Programming connection is
shown in Figure 14-11.
In-Circuit Serial Programming™
The PIC16F882/883/884/886/887 microcontrollers can
be serially programmed while in the end application circuit. This is simply done with two lines for clock and
data and three other lines for:
• power
• ground
• 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.
© 2009 Microchip Technology Inc.
DS41291F-page 227
PIC16F882/883/884/886/887
FIGURE 14-11:
TYPICAL IN-CIRCUIT
SERIAL
PROGRAMMING™
CONNECTION
To Normal
Connections
External
Connector
Signals
PIC16F882/883/
884/886/887
*
+5V
VDD
0V
VSS
VPP
RE3/MCLR/VPP
CLK
RB6
Data I/O
RB7
*
*
*
To Normal
Connections
*
Isolation devices (as required)
14.10 Low-Voltage (Single-Supply) ICSP
Programming
The LVP bit of the Configuration Word enables
low-voltage ICSP programming. This mode allows the
microcontroller to be programmed via ICSP using a
VDD source in the operating voltage range. This only
means that VPP does not have to be brought to VIHH but
can instead be left at the normal operating voltage. In
this mode, the RB3/PGM pin is dedicated to the
programming function and ceases to be a general
purpose I/O pin. During programming, VDD is applied to
the MCLR pin. To enter Programming mode, VDD must
be applied to the RB3/PGM provided the LVP bit is set.
The LVP bit defaults to on (‘1’) from the factory.
Note 1: The High-Voltage Programming mode is
always available, regardless of the state
of the LVP bit, by applying VIHH to the
MCLR pin.
2: While in Low-Voltage ICSP mode, the
RB3 pin can no longer be used as a
general purpose I/O pin.
3: When using Low-Voltage ICSP Programming (LVP) and the pull-ups on PORTB
are enabled, bit 3 in the TRISB register
must be cleared to disable the pull-up on
RB3 and ensure the proper operation of
the device.
4: RB3 should not be allowed to float if LVP
is enabled. An external pull-down device
should be used to default the device to
normal operating mode. If RB3 floats
high, the PIC16F882/883/884/886/887
device will enter Programming mode.
5: LVP mode is enabled by default on all
devices shipped from Microchip. It can be
disabled by clearing the LVP bit in the
CONFIG register.
If Low-Voltage Programming mode is not used, the LVP
bit can be programmed to a ‘0’ and RB3/PGM becomes
a digital I/O pin. However, the LVP bit may only be
programmed when programming is entered with VIHH
on MCLR. The LVP bit can only be charged when using
high voltage on MCLR.
It should be noted, that once the LVP bit is programmed
to ‘0’, only the High-Voltage Programming mode is
available and only High-Voltage Programming mode
can be used to program the device.
When using low-voltage ICSP, the part must be
supplied at 4.5V to 5.5V if a bulk erase will be executed.
This includes reprogramming of the code-protect bits
from an on state to an off state. For all other cases of
low-voltage ICSP, the part may be programmed at the
normal operating voltage. This means calibration
values, unique user IDs or user code can be
reprogrammed or added.
DS41291F-page 228
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
For more information, see “Using MPLAB® ICD 2”
(DS51265), available on Microchip’s web site
(www.microchip.com).
14.11 In-Circuit Debugger
The PIC16F882/883/884/886/887-ICD can be used in
any of the package types. The device will be mounted
on the target application board, which in turn has a 3 or
4 wire connection to the ICD tool.
14.11.1 ICD PINOUT
The devices in the PIC16F88X family carry the
circuitry for the In-Circuit Debugger on-chip and on
existing device pins. This eliminates the need for a
separate die or package for the ICD device. The pinout
for the ICD device is the same as the devices (see
Section 1.0 “Device Overview” for complete pinout
and pin descriptions). Table 14-9 shows the location
and function of the ICD related pins on the 28 and 40
pin devices.
When the debug bit in the Configuration Word
(CONFIG<13>) is programmed to a ‘0’, the In-Circuit
Debugger functionality is enabled. This function allows
simple debugging functions when used with MPLAB®
ICD 2. When the microcontroller has this feature
enabled, some of the resources are not available for
general use. See Table 14-9 for more detail.
Note: The user’s application must have the
circuitry
required
to
support
ICD
functionality. Once the ICD circuitry is
enabled, normal device pin functions on
RB6/ICSPCLK and RB7/ICSPDAT will not
be usable. The ICD circuitry uses these pins
for communication with the ICD2 external
debugger.
TABLE 14-9:
PIC16F883/884/886/887-ICD PIN DESCRIPTIONS
Pin (PDIP)
PIC16F882/883/
886
Name
Type
Pull-up
PIC16F884/887
40
28
ICDDATA
TTL
—
In-Circuit Debugger Bidirectional data
39
27
ICDCLK
ST
—
In-Circuit Debugger Bidirectional clock
Programming voltage
1
1
MCLR/VPP
HV
—
11,32
20
VDD
P
—
12,31
8,19
VSS
P
—
Description
Legend: TTL = TTL input buffer, ST = Schmitt Trigger input buffer, P = Power, HV = High Voltage
© 2009 Microchip Technology Inc.
DS41291F-page 229
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 230
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
15.0
INSTRUCTION SET SUMMARY
The PIC16F882/883/884/886/887 instruction set is
highly orthogonal and is comprised of three basic categories:
TABLE 15-1:
OPCODE FIELD
DESCRIPTIONS
Field
Description
Register file address (0x00 to 0x7F)
f
• Byte-oriented operations
• Bit-oriented operations
• Literal and control operations
W
Working register (accumulator)
b
Bit address within an 8-bit file register
k
Literal field, constant data or label
Each PIC16 instruction is a 14-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 formats for each of the categories
is presented in Figure 15-1, while the various opcode
fields are summarized in Table 15-1.
x
Don’t care location (= 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.
d
Destination select; d = 0: store result in W,
d = 1: store result in file register f.
Default is d = 1.
Table 15-2 lists the instructions recognized by the
MPASMTM assembler.
For byte-oriented instructions, ‘f’ represents a file
register designator and ‘d’ represents a destination
designator. The file register designator specifies which
file register is to be used by the instruction.
The destination designator specifies where the result of
the operation is to be placed. If ‘d’ is zero, the result is
placed in the W register. If ‘d’ is one, the result is placed
in the file register specified in the instruction.
For bit-oriented instructions, ‘b’ represents a bit field
designator, which selects the bit affected by the
operation, while ‘f’ represents the address of the file in
which the bit is located.
For literal and control operations, ‘k’ represents an
8-bit or 11-bit constant, or literal value.
One instruction cycle consists of four oscillator periods;
for an oscillator frequency of 4 MHz, this gives a normal
instruction execution time of 1 μs. All instructions are
executed within a single instruction cycle, unless a
conditional test is true, or the program counter is
changed as a result of an instruction. When this occurs,
the execution takes two instruction cycles, with the
second cycle executed as a NOP.
All instruction examples use the format ‘0xhh’ to
represent a hexadecimal number, where ‘h’ signifies a
hexadecimal digit.
PC
Program Counter
TO
Time-out bit
Carry bit
C
DC
Digit carry bit
Zero bit
Z
PD
Power-down bit
FIGURE 15-1:
GENERAL FORMAT FOR
INSTRUCTIONS
Byte-oriented file register operations
13
8 7 6
OPCODE
d
f (FILE #)
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
Bit-oriented file register operations
13
10 9
7 6
OPCODE
b (BIT #)
f (FILE #)
Literal and control operations
General
8
7
OPCODE
Read-Modify-Write Operations
Any instruction that specifies a file register as part of
the instruction performs a Read-Modify-Write (RMW)
operation. The register is read, the data is modified,
and the result is stored according to either the instruction, or the destination designator ‘d’. A read operation
is performed on a register even if the instruction writes
to that register.
0
b = 3-bit bit address
f = 7-bit file register address
13
15.1
0
0
k (literal)
k = 8-bit immediate value
CALL and GOTO instructions only
13
11
OPCODE
10
0
k (literal)
k = 11-bit immediate value
For example, a CLRF PORTA instruction will read
PORTA, clear all the data bits, then write the result back
to PORTA. This example would have the unintended
consequence of clearing the condition that set the RAIF
flag.
© 2009 Microchip Technology Inc.
DS41291F-page 231
PIC16F882/883/884/886/887
TABLE 15-2:
PIC16F882/883/884/886/887 INSTRUCTION SET
Mnemonic,
Operands
14-Bit Opcode
Description
Cycles
MSb
LSb
Status
Affected
Notes
BYTE-ORIENTED FILE REGISTER OPERATIONS
ADDWF
ANDWF
CLRF
CLRW
COMF
DECF
DECFSZ
INCF
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
f, d
f, d
f
–
f, d
f, d
f, d
f, d
f, d
f, d
f, d
f
–
f, d
f, d
f, d
f, d
f, d
Add W and f
AND W with f
Clear f
Clear W
Complement f
Decrement f
Decrement f, Skip if 0
Increment f
Increment f, Skip if 0
Inclusive OR W with f
Move f
Move W to f
No Operation
Rotate Left f through Carry
Rotate Right f through Carry
Subtract W from f
Swap nibbles in f
Exclusive OR W with f
BCF
BSF
BTFSC
BTFSS
f, b
f, b
f, b
f, b
Bit Clear f
Bit Set f
Bit Test f, Skip if Clear
Bit Test f, Skip if Set
1
1
1
1
1
1
1(2)
1
1(2)
1
1
1
1
1
1
1
1
1
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
dfff
dfff
lfff
0xxx
dfff
dfff
dfff
dfff
dfff
dfff
dfff
lfff
0xx0
dfff
dfff
dfff
dfff
dfff
ffff
ffff
ffff
xxxx
ffff
ffff
ffff
ffff
ffff
ffff
ffff
ffff
0000
ffff
ffff
ffff
ffff
ffff
00bb
01bb
10bb
11bb
bfff
bfff
bfff
bfff
ffff
ffff
ffff
ffff
111x
1001
0kkk
0000
1kkk
1000
00xx
0000
01xx
0000
0000
110x
1010
kkkk
kkkk
kkkk
0110
kkkk
kkkk
kkkk
0000
kkkk
0000
0110
kkkk
kkkk
kkkk
kkkk
kkkk
0100
kkkk
kkkk
kkkk
1001
kkkk
1000
0011
kkkk
kkkk
0111
0101
0001
0001
1001
0011
1011
1010
1111
0100
1000
0000
0000
1101
1100
0010
1110
0110
C, DC, Z
Z
Z
Z
Z
Z
Z
Z
Z
C
C
C, DC, Z
Z
1, 2
1, 2
2
1, 2
1, 2
1, 2, 3
1, 2
1, 2, 3
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
1, 2
BIT-ORIENTED FILE REGISTER OPERATIONS
1
1
1 (2)
1 (2)
01
01
01
01
1, 2
1, 2
3
3
LITERAL AND CONTROL OPERATIONS
ADDLW
ANDLW
CALL
CLRWDT
GOTO
IORLW
MOVLW
RETFIE
RETLW
RETURN
SLEEP
SUBLW
XORLW
Note 1:
2:
3:
k
k
k
–
k
k
k
–
k
–
–
k
k
Add literal and W
AND literal with W
Call Subroutine
Clear Watchdog Timer
Go to address
Inclusive OR literal with W
Move literal to W
Return from interrupt
Return with literal in W
Return from Subroutine
Go into Standby mode
Subtract W from literal
Exclusive OR literal with W
1
1
2
1
2
1
1
2
2
2
1
1
1
11
11
10
00
10
11
11
00
11
00
00
11
11
C, DC, Z
Z
TO, PD
Z
TO, PD
C, DC, Z
Z
When an I/O register is modified as a function of itself (e.g., MOVF GPIO, 1), 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 to the Timer0 module.
If the Program Counter (PC) is modified, or a conditional test is true, the instruction requires two cycles. The second
cycle is executed as a NOP.
DS41291F-page 232
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
15.2
Instruction Descriptions
ADDLW
Add literal and W
Syntax:
[ label ] ADDLW
Operands:
0 ≤ k ≤ 255
Operation:
(W) + k → (W)
Status Affected:
C, DC, Z
Description:
The contents of the W register
are added to the eight-bit literal ‘k’
and the result is placed in the
W register.
k
BCF
Bit Clear f
Syntax:
[ label ] BCF
Operands:
0 ≤ f ≤ 127
0≤b≤7
Operation:
0 → (f<b>)
Status Affected:
None
Description:
Bit ‘b’ in register ‘f’ is cleared.
BSF
Bit Set f
Syntax:
[ label ] BSF
f,b
ADDWF
Add W and f
Syntax:
[ label ] ADDWF
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
0≤b≤7
Operation:
(W) + (f) → (destination)
Operation:
1 → (f<b>)
Status Affected:
C, DC, Z
Status Affected:
None
Description:
Add the contents of the W register
with register ‘f’. If ‘d’ is ‘0’, the
result is stored in the W register. If
‘d’ is ‘1’, the result is stored back
in register ‘f’.
Description:
Bit ‘b’ in register ‘f’ is set.
ANDLW
AND literal with W
BTFSC
Bit Test f, Skip if Clear
Syntax:
[ label ] ANDLW
Syntax:
[ label ] BTFSC f,b
Operands:
0 ≤ k ≤ 255
Operands:
Operation:
(W) .AND. (k) → (W)
0 ≤ f ≤ 127
0≤b≤7
Status Affected:
Z
Operation:
skip if (f<b>) = 0
Description:
The contents of W register are
AND’ed with the eight-bit literal
‘k’. The result is placed in the W
register.
Status Affected:
None
Description:
If bit ‘b’ in register ‘f’ is ‘1’, the next
instruction is executed.
If bit ‘b’ in register ‘f’ is ‘0’, the next
instruction is discarded, and a NOP
is executed instead, making this a
two-cycle instruction.
ANDWF
f,d
k
AND W with f
Syntax:
[ label ] ANDWF
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(W) .AND. (f) → (destination)
f,d
Status Affected:
Z
Description:
AND the W register with register
‘f’. If ‘d’ is ‘0’, the result is stored in
the W register. If ‘d’ is ‘1’, the
result is stored back in register ‘f’.
© 2009 Microchip Technology Inc.
f,b
DS41291F-page 233
PIC16F882/883/884/886/887
BTFSS
Bit Test f, Skip if Set
CLRWDT
Clear Watchdog Timer
Syntax:
[ label ] BTFSS f,b
Syntax:
[ label ] CLRWDT
Operands:
0 ≤ f ≤ 127
0≤b<7
Operands:
None
Operation:
00h → WDT
0 → WDT prescaler,
1 → TO
1 → PD
Status Affected:
TO, PD
Description:
CLRWDT instruction resets the
Watchdog Timer. It also resets the
prescaler of the WDT.
Status bits TO and PD are set.
Operation:
skip if (f<b>) = 1
Status Affected:
None
Description:
If bit ‘b’ in register ‘f’ is ‘0’, the next
instruction is executed.
If bit ‘b’ is ‘1’, then the next
instruction is discarded and a NOP
is executed instead, making this a
two-cycle instruction.
CALL
Call Subroutine
COMF
Complement f
Syntax:
[ label ] CALL k
Syntax:
[ label ] COMF
Operands:
0 ≤ k ≤ 2047
Operands:
Operation:
(PC)+ 1→ TOS,
k → PC<10:0>,
(PCLATH<4:3>) → PC<12:11>
0 ≤ f ≤ 127
d ∈ [0,1]
f,d
Operation:
(f) → (destination)
Status Affected:
Z
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’.
DECF
Decrement f
Syntax:
[ label ] DECF f,d
Status Affected:
None
Description:
Call Subroutine. First, return
address (PC + 1) is pushed onto
the stack. The eleven-bit
immediate address is loaded into
PC bits <10:0>. The upper bits of
the PC are loaded from PCLATH.
CALL is a two-cycle instruction.
CLRF
Clear f
Syntax:
[ label ] CLRF
Operands:
0 ≤ f ≤ 127
Operands:
Operation:
00h → (f)
1→Z
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - 1 → (destination)
Status Affected:
Z
Status Affected:
Z
Description:
The contents of register ‘f’ are
cleared and the Z bit is set.
Description:
Decrement register ‘f’. If ‘d’ is ‘0’,
the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
CLRW
Clear W
Syntax:
[ label ] CLRW
f
Operands:
None
Operation:
00h → (W)
1→Z
Status Affected:
Z
Description:
W register is cleared. Zero bit (Z)
is set.
DS41291F-page 234
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
DECFSZ
Decrement f, Skip if 0
INCFSZ
Increment f, Skip if 0
Syntax:
[ label ] DECFSZ f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - 1 → (destination);
skip if result = 0
Operation:
(f) + 1 → (destination),
skip if result = 0
Status Affected:
None
Status Affected:
None
Description:
The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
If the result is ‘1’, the next
instruction is executed. If the
result is ‘0’, then a NOP is
executed instead, making it a
two-cycle instruction.
Description:
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
If the result is ‘1’, the next
instruction is executed. If the
result is ‘0’, a NOP is executed
instead, making it a two-cycle
instruction.
GOTO
Unconditional Branch
IORLW
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 2047
Operands:
0 ≤ k ≤ 255
Operation:
k → PC<10:0>
PCLATH<4:3> → PC<12:11>
Operation:
(W) .OR. k → (W)
Status Affected:
Z
Status Affected:
None
Description:
Description:
GOTO is an unconditional branch.
The eleven-bit immediate value is
loaded into PC bits <10:0>. The
upper bits of PC are loaded from
PCLATH<4:3>. GOTO is a
two-cycle instruction.
The contents of the W register are
OR’ed with the eight-bit literal ‘k’.
The result is placed in the
W register.
INCF
Increment f
IORWF
Inclusive OR W with f
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) + 1 → (destination)
Operation:
(W) .OR. (f) → (destination)
Status Affected:
Z
Status Affected:
Z
Description:
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
Description:
Inclusive OR the W register with
register ‘f’. If ‘d’ is ‘0’, the result is
placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
GOTO k
INCF f,d
© 2009 Microchip Technology Inc.
INCFSZ f,d
Inclusive OR literal with W
IORLW k
IORWF
f,d
DS41291F-page 235
PIC16F882/883/884/886/887
MOVF
Move f
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
MOVF f,d
MOVWF
Move W to f
Syntax:
[ label ]
MOVWF
Operands:
0 ≤ f ≤ 127
Operation:
(W) → (f)
f
Operation:
(f) → (dest)
Status Affected:
None
Status Affected:
Z
Description:
Description:
The contents of register ‘f’ is
moved to a destination dependent
upon the status of ‘d’. If d = 0,
destination is W register. If d = 1,
the destination is file register ‘f’
itself. d = 1 is useful to test a file
register since status flag Z is
affected.
Move data from W register to
register ‘f’.
Words:
1
Cycles:
1
Words:
1
Cycles:
1
Example:
MOVF
Example:
MOVW
F
OPTION
Before Instruction
OPTION =
W
=
After Instruction
OPTION =
W
=
FSR, 0
0xFF
0x4F
0x4F
0x4F
After Instruction
W =
value in FSR
register
Z = 1
MOVLW
Move literal to W
NOP
No Operation
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
None
Operation:
k → (W)
Operation:
No operation
Status Affected:
None
Status Affected:
None
Description:
The eight-bit literal ‘k’ is loaded into
W register. The “don’t cares” will
assemble as ‘0’s.
Description:
No operation.
Words:
1
Cycles:
1
Words:
1
Cycles:
1
Example:
MOVLW k
Example:
MOVLW
NOP
0x5A
After Instruction
W =
DS41291F-page 236
NOP
0x5A
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
RETFIE
Return from Interrupt
RETLW
Return with literal in W
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
None
Operands:
0 ≤ k ≤ 255
Operation:
TOS → PC,
1 → GIE
Operation:
k → (W);
TOS → PC
Status Affected:
None
Status Affected:
None
Description:
Return from Interrupt. Stack is
POPed and Top-of-Stack (TOS) is
loaded in the PC. Interrupts are
enabled by setting Global
Interrupt Enable bit, GIE
(INTCON<7>). This is a two-cycle
instruction.
Description:
The W register is loaded with the
eight-bit literal ‘k’. The program
counter is loaded from the top of
the stack (the return address).
This is a two-cycle instruction.
Words:
1
Cycles:
2
Example:
RETFIE
Words:
1
Cycles:
2
Example:
RETFIE
After Interrupt
PC =
GIE =
TABLE
TOS
1
RETLW k
CALL TABLE;W contains
table
;offset value
•
;W now has
•
;table value
•
•
ADDWF PC ;W = offset
RETLW k1 ;Begin table
RETLW k2 ;
•
•
•
RETLW kn ;End of table
Before Instruction
W = 0x07
After Instruction
W = value of k8
© 2009 Microchip Technology Inc.
RETURN
Return from Subroutine
Syntax:
[ label ]
Operands:
None
Operation:
TOS → PC
Status Affected:
None
Description:
Return from subroutine. The stack
is POPed and the top of the stack
(TOS) is loaded into the program
counter. This is a two-cycle
instruction.
RETURN
DS41291F-page 237
PIC16F882/883/884/886/887
RLF
Rotate Left f through Carry
SLEEP
Enter Sleep mode
Syntax:
[ label ]
Syntax:
[ label ] SLEEP
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
None
Operation:
Operation:
See description below
Status Affected:
C
Description:
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 the W register.
If ‘d’ is ‘1’, the result is stored
back in register ‘f’.
00h → WDT,
0 → WDT prescaler,
1 → TO,
0 → PD
RLF
f,d
C
Words:
1
Cycles:
1
Example:
Status Affected:
TO, PD
Description:
The power-down Status bit, PD is
cleared. Time-out Status bit, TO
is set. Watchdog Timer and its
prescaler are cleared.
The processor is put into Sleep
mode with the oscillator stopped.
Register f
RLF
REG1,0
Before Instruction
REG1
C
=
=
1110 0110
0
=
=
=
1110 0110
1100 1100
1
After Instruction
REG1
W
C
RRF
Rotate Right f through Carry
SUBLW
Syntax:
[ label ]
Syntax:
[ label ] SUBLW k
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ k ≤ 255
Operation:
k - (W) → (W)
Operation:
See description below
Status Affected: C, DC, Z
Status Affected:
C
Description:
Description:
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 the W register.
If ‘d’ is ‘1’, the result is placed
back in register ‘f’.
RRF f,d
C
DS41291F-page 238
Register f
Subtract W from literal
The W register is subtracted (2’s
complement method) from the
eight-bit literal ‘k’. The result is
placed in the W register.
C=0
W>k
C=1
W≤k
DC = 0
W<3:0> > k<3:0>
DC = 1
W<3:0> ≤ k<3:0>
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
SUBWF
Subtract W from f
XORWF
Exclusive OR W with f
Syntax:
[ label ] SUBWF f,d
Syntax:
[ label ] XORWF
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f) - (W) → (destination)
Operation:
(W) .XOR. (f) → (destination)
Status Affected: C, DC, Z
Status Affected:
Z
Description:
Description:
Exclusive OR the contents of the
W register with register ‘f’. If ‘d’ is
‘0’, the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
Subtract (2’s complement method)
W register from register ‘f’. If ‘d’ is
‘0’, the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
C=0
W>f
C=1
W≤f
DC = 0
W<3:0> > f<3:0>
DC = 1
W<3:0> ≤ f<3:0>
SWAPF
Swap Nibbles in f
Syntax:
[ label ] SWAPF f,d
Operands:
0 ≤ f ≤ 127
d ∈ [0,1]
Operation:
(f<3:0>) → (destination<7:4>),
(f<7:4>) → (destination<3:0>)
Status Affected:
None
Description:
The upper and lower nibbles of
register ‘f’ are exchanged. If ‘d’ is
‘0’, the result is placed in the W
register. If ‘d’ is ‘1’, the result is
placed in register ‘f’.
XORLW
f,d
Exclusive OR literal with W
Syntax:
[ label ] XORLW k
Operands:
0 ≤ k ≤ 255
Operation:
(W) .XOR. k → (W)
Status Affected:
Z
Description:
The contents of the W register
are XOR’ed with the eight-bit
literal ‘k’. The result is placed in
the W register.
© 2009 Microchip Technology Inc.
DS41291F-page 239
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 240
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
16.0
DEVELOPMENT SUPPORT
The PIC® microcontrollers are supported with a full
range of hardware and software development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Assemblers/Compilers/Linkers
- MPASMTM Assembler
- MPLAB C18 and MPLAB C30 C Compilers
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
- MPLAB ASM30 Assembler/Linker/Library
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB ICE 2000 In-Circuit Emulator
- MPLAB REAL ICE™ In-Circuit Emulator
• In-Circuit Debugger
- MPLAB ICD 2
• Device Programmers
- PICSTART® Plus Development Programmer
- MPLAB PM3 Device Programmer
- PICkit™ 2 Development Programmer
• Low-Cost Demonstration and Development
Boards and Evaluation Kits
16.1
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8/16-bit microcontroller market. The MPLAB IDE is a Windows®
operating system-based application that contains:
• A single graphical interface to all debugging tools
- Simulator
- Programmer (sold separately)
- Emulator (sold separately)
- In-Circuit Debugger (sold separately)
• A full-featured editor with color-coded context
• A multiple project manager
• Customizable data windows with direct edit of
contents
• High-level source code debugging
• Visual device initializer for easy register
initialization
• Mouse over variable inspection
• Drag and drop variables from source to watch
windows
• Extensive on-line help
• Integration of select third party tools, such as
HI-TECH Software C Compilers and IAR
C Compilers
The MPLAB IDE allows you to:
• Edit your source files (either assembly or C)
• One touch assemble (or compile) and download
to PIC MCU emulator and simulator tools
(automatically updates all project information)
• Debug using:
- Source files (assembly or C)
- Mixed assembly and C
- Machine code
MPLAB IDE supports multiple debugging tools in a
single development paradigm, from the cost-effective
simulators, through low-cost in-circuit debuggers, to
full-featured emulators. This eliminates the learning
curve when upgrading to tools with increased flexibility
and power.
© 2009 Microchip Technology Inc.
DS41291F-page 241
PIC16F882/883/884/886/887
16.2
MPASM Assembler
The MPASM Assembler is a full-featured, universal
macro assembler for all PIC MCUs.
The MPASM Assembler generates relocatable object
files for the MPLINK Object Linker, Intel® standard HEX
files, MAP files to detail memory usage and symbol
reference, absolute LST files that contain source lines
and generated machine code and COFF files for
debugging.
The MPASM Assembler features include:
• Integration into MPLAB IDE projects
• User-defined macros to streamline
assembly code
• Conditional assembly for multi-purpose
source files
• Directives that allow complete control over the
assembly process
16.5
MPLAB ASM30 Assembler produces relocatable
machine code from symbolic assembly language for
dsPIC30F devices. MPLAB C30 C Compiler uses the
assembler to produce its object file. The assembler
generates relocatable object files that can then be
archived or linked with other relocatable object files and
archives to create an executable file. Notable features
of the assembler include:
•
•
•
•
•
•
Support for the entire dsPIC30F instruction set
Support for fixed-point and floating-point data
Command line interface
Rich directive set
Flexible macro language
MPLAB IDE compatibility
16.6
16.3
MPLAB C18 and MPLAB C30
C Compilers
The MPLAB C18 and MPLAB C30 Code Development
Systems are complete ANSI C compilers for
Microchip’s PIC18 and PIC24 families of microcontrollers and the dsPIC30 and dsPIC33 family of digital
signal controllers. These compilers provide powerful
integration capabilities, superior code optimization and
ease of use not found with other compilers.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
16.4
MPLINK Object Linker/
MPLIB Object Librarian
The MPLINK Object Linker combines relocatable
objects created by the MPASM Assembler and the
MPLAB C18 C Compiler. It can link relocatable objects
from precompiled libraries, using directives from a
linker script.
MPLAB ASM30 Assembler, Linker
and Librarian
MPLAB SIM Software Simulator
The MPLAB SIM Software Simulator allows code
development in a PC-hosted environment by simulating the PIC MCUs and dsPIC® DSCs on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a comprehensive stimulus controller. Registers can be
logged to files for further run-time analysis. The trace
buffer and logic analyzer display extend the power of
the simulator to record and track program execution,
actions on I/O, most peripherals and internal registers.
The MPLAB SIM Software Simulator fully supports
symbolic debugging using the MPLAB C18 and
MPLAB C30 C Compilers, and the MPASM and
MPLAB ASM30 Assemblers. The software simulator
offers the flexibility to develop and debug code outside
of the hardware laboratory environment, making it an
excellent, economical software development tool.
The MPLIB Object Librarian manages the creation and
modification of library files of precompiled code. When
a routine from a library is called from a source file, only
the modules that contain that routine will be linked in
with the application. This allows large libraries to be
used efficiently in many different applications.
The object linker/library features include:
• Efficient linking of single libraries instead of many
smaller files
• Enhanced code maintainability by grouping
related modules together
• Flexible creation of libraries with easy module
listing, replacement, deletion and extraction
DS41291F-page 242
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
16.7
MPLAB ICE 2000
High-Performance
In-Circuit Emulator
The MPLAB ICE 2000 In-Circuit Emulator is intended
to provide the product development engineer with a
complete microcontroller design tool set for PIC
microcontrollers. Software control of the MPLAB ICE
2000 In-Circuit Emulator is advanced by the MPLAB
Integrated Development Environment, which allows
editing, building, downloading and source debugging
from a single environment.
The MPLAB ICE 2000 is a full-featured emulator
system with enhanced trace, trigger and data monitoring features. Interchangeable processor modules allow
the system to be easily reconfigured for emulation of
different processors. The architecture of the MPLAB
ICE 2000 In-Circuit Emulator allows expansion to
support new PIC microcontrollers.
The MPLAB ICE 2000 In-Circuit Emulator system has
been designed as a real-time emulation system with
advanced features that are typically found on more
expensive development tools. The PC platform and
Microsoft® Windows® 32-bit operating system were
chosen to best make these features available in a
simple, unified application.
16.8
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® and dsPIC® Flash microcontrollers with
the easy-to-use, powerful graphical user interface of the
MPLAB Integrated Development Environment (IDE),
included with each kit.
The MPLAB REAL ICE probe is connected to the design
engineer’s PC using a high-speed USB 2.0 interface and
is connected to the target with either a connector
compatible with the popular MPLAB ICD 2 system
(RJ11) or with the new high speed, noise tolerant, lowvoltage differential signal (LVDS) interconnection
(CAT5).
16.9
MPLAB ICD 2 In-Circuit Debugger
Microchip’s In-Circuit Debugger, MPLAB ICD 2, is a
powerful, low-cost, run-time development tool,
connecting to the host PC via an RS-232 or high-speed
USB interface. This tool is based on the Flash PIC
MCUs and can be used to develop for these and other
PIC MCUs and dsPIC DSCs. The MPLAB ICD 2 utilizes
the in-circuit debugging capability built into the Flash
devices. This feature, along with Microchip’s In-Circuit
Serial ProgrammingTM (ICSPTM) protocol, offers costeffective, in-circuit Flash debugging from the graphical
user interface of the MPLAB Integrated Development
Environment. This enables a designer to develop and
debug source code by setting breakpoints, single stepping and watching variables, and CPU status and
peripheral registers. Running at full speed enables
testing hardware and applications in real time. MPLAB
ICD 2 also serves as a development programmer for
selected PIC devices.
16.10 MPLAB PM3 Device Programmer
The MPLAB PM3 Device Programmer is a universal,
CE compliant device programmer with programmable
voltage verification at VDDMIN and VDDMAX for
maximum reliability. It features a large LCD display
(128 x 64) for menus and error messages and a modular, detachable socket assembly to support various
package types. The ICSP™ cable assembly is included
as a standard item. In Stand-Alone mode, the MPLAB
PM3 Device Programmer can read, verify and program
PIC devices without a PC connection. It can also set
code protection in this mode. The MPLAB PM3
connects to the host PC via an RS-232 or USB cable.
The MPLAB PM3 has high-speed communications and
optimized algorithms for quick programming of large
memory devices and incorporates an SD/MMC card for
file storage and secure data applications.
MPLAB REAL ICE is field upgradeable through future
firmware downloads in MPLAB IDE. In upcoming
releases of MPLAB IDE, new devices will be supported,
and new features will be added, such as software breakpoints and assembly code trace. MPLAB REAL ICE
offers significant advantages over competitive emulators
including low-cost, full-speed emulation, real-time
variable watches, trace analysis, complex breakpoints, a
ruggedized probe interface and long (up to three meters)
interconnection cables.
© 2009 Microchip Technology Inc.
DS41291F-page 243
PIC16F882/883/884/886/887
16.11 PICSTART Plus Development
Programmer
16.13 Demonstration, Development and
Evaluation Boards
The PICSTART Plus Development Programmer is an
easy-to-use, low-cost, prototype programmer. It
connects to the PC via a COM (RS-232) port. MPLAB
Integrated Development Environment software makes
using the programmer simple and efficient. The
PICSTART Plus Development Programmer supports
most PIC devices in DIP packages up to 40 pins.
Larger pin count devices, such as the PIC16C92X and
PIC17C76X, may be supported with an adapter socket.
The PICSTART Plus Development Programmer is CE
compliant.
A wide variety of demonstration, development and
evaluation boards for various PIC MCUs and dsPIC
DSCs allows quick application development on fully functional systems. Most boards include prototyping areas for
adding custom circuitry and provide application firmware
and source code for examination and modification.
16.12 PICkit 2 Development Programmer
The PICkit™ 2 Development Programmer is a low-cost
programmer and selected Flash device debugger with
an easy-to-use interface for programming many of
Microchip’s baseline, mid-range and PIC18F families of
Flash memory microcontrollers. The PICkit 2 Starter Kit
includes a prototyping development board, twelve
sequential lessons, software and HI-TECH’s PICC™
Lite C compiler, and is designed to help get up to speed
quickly using PIC® microcontrollers. The kit provides
everything needed to program, evaluate and develop
applications using Microchip’s powerful, mid-range
Flash memory family of microcontrollers.
DS41291F-page 244
The boards support a variety of features, including LEDs,
temperature sensors, switches, speakers, RS-232
interfaces, LCD displays, potentiometers and additional
EEPROM memory.
The demonstration and development boards can be
used in teaching environments, for prototyping custom
circuits and for learning about various microcontroller
applications.
In addition to the PICDEM™ and dsPICDEM™ demonstration/development board series of circuits, Microchip
has a line of evaluation kits and demonstration software
for analog filter design, KEELOQ® security ICs, CAN,
IrDA®, PowerSmart® battery management, SEEVAL®
evaluation system, Sigma-Delta ADC, flow rate
sensing, plus many more.
Check the Microchip web page (www.microchip.com)
and the latest “Product Selector Guide” (DS00148) for
the complete list of demonstration, development and
evaluation kits.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.0
ELECTRICAL SPECIFICATIONS
Absolute Maximum Ratings(†)
Ambient temperature under bias..........................................................................................................-40° to +125°C
Storage temperature ........................................................................................................................ -65°C to +150°C
Voltage on VDD with respect to VSS ................................................................................................... -0.3V to +6.5V
Voltage on MCLR with respect to Vss ............................................................................................... -0.3V to +13.5V
Voltage on all other pins with respect to VSS ........................................................................... -0.3V to (VDD + 0.3V)
Total power dissipation(1) ............................................................................................................................... 800 mW
Maximum current out of VSS pin ...................................................................................................................... 95 mA
Maximum current into VDD pin ......................................................................................................................... 95 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 (combined)(2) ............................................................................................ 90 mA
Maximum current sourced by all ports (combined)(2) ....................................................................................... 90 mA
Note 1:
2:
Power dissipation is calculated as follows: PDIS = VDD x {IDD – ∑ IOH} + ∑ {(VDD – VOH) x IOH} + ∑(VOl x IOL).
PORTD and PORTE are implemented on PIC16F886/PIC16F887 only.
† 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 above maximum rating conditions for
extended periods may affect device reliability.
© 2009 Microchip Technology Inc.
DS41291F-page 245
PIC16F882/883/884/886/887
FIGURE 17-1:
PIC16F883/884/886/887 VOLTAGE-FREQUENCY GRAPH,
-40°C ≤ TA ≤ +125°C
5.5
5.0
VDD (V)
4.5
4.0
3.5
3.0
2.5
2.0
0
8
10
20
Frequency (MHz)
Note 1: The shaded region indicates the permissible combinations of voltage and frequency.
HFINTOSC FREQUENCY ACCURACY OVER DEVICE VDD AND TEMPERATURE
FIGURE 17-2:
125
± 5%
Temperature (°C)
85
± 2%
60
± 1%
25
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS41291F-page 246
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.1
DC Characteristics: PIC16F883/884/886/887-I (Industrial)
PIC16F883/884/886/887-E (Extended)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Param
No.
Min. Typ† Max. Units
Sym.
Characteristic
Conditions
VDD
Supply Voltage
2.0
2.0
3.0
4.5
—
—
—
—
5.5
5.5
5.5
5.5
V
V
V
V
FOSC < = 8 MHz: HFINTOSC, EC
FOSC < = 4 MHz
FOSC < = 10 MHz
FOSC < = 20 MHz
D002*
VDR
RAM Data Retention
Voltage(1)
1.5
—
—
V
Device in Sleep mode
D003
VPOR
VDD Start Voltage to
ensure internal Power-on
Reset signal
—
VSS
—
V
See Section 14.2.1 “Power-on Reset
(POR)” for details.
D004*
SVDD
VDD Rise Rate to ensure
internal Power-on Reset
signal
0.05
—
—
D001
D001C
D001D
V/ms See Section 14.2.1 “Power-on Reset
(POR)” for details.
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: This is the limit to which VDD can be lowered in Sleep mode without losing RAM data.
© 2009 Microchip Technology Inc.
DS41291F-page 247
PIC16F882/883/884/886/887
17.2
DC Characteristics: PIC16F883/884/886/887-I (Industrial)
PIC16F883/884/886/887-E (Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
DC CHARACTERISTICS
Param
No.
D010
Conditions
Device Characteristics
Min.
Typ†
Max.
Units
VDD
Supply Current (IDD)
D011*
D012
D013*
D014
D015
D016*
D017
D018
D019
(1, 2)
—
13
19
μA
2.0
—
22
30
μA
3.0
—
33
60
μA
5.0
—
180
250
μA
2.0
—
290
400
μA
3.0
—
490
650
μA
5.0
—
280
380
μA
2.0
—
480
670
μA
3.0
—
0.9
1.4
mA
5.0
—
170
295
μA
2.0
—
280
480
μA
3.0
—
470
690
μA
5.0
—
290
450
μA
2.0
—
490
720
μA
3.0
—
0.85
1.3
mA
5.0
—
8
20
μA
2.0
—
16
40
μA
3.0
—
31
65
μA
5.0
—
416
520
μA
2.0
—
640
840
μA
3.0
—
1.13
1.6
mA
5.0
—
0.65
0.9
mA
2.0
—
1.01
1.3
mA
3.0
—
1.86
2.3
mA
5.0
—
340
580
μA
2.0
—
550
900
μA
3.0
—
0.92
1.4
mA
5.0
—
3.8
4.7
mA
4.5
—
4.0
4.8
mA
5.0
Note
FOSC = 32 kHz
LP Oscillator mode
FOSC = 1 MHz
XT Oscillator mode
FOSC = 4 MHz
XT Oscillator mode
FOSC = 1 MHz
EC Oscillator mode
FOSC = 4 MHz
EC Oscillator mode
FOSC = 31 kHz
LFINTOSC mode
FOSC = 4 MHz
HFINTOSC mode
FOSC = 8 MHz
HFINTOSC mode
FOSC = 4 MHz
EXTRC mode(3)
FOSC = 20 MHz
HS Oscillator mode
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: 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 disabled.
2: The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O
pin loading and switching rate, oscillator type, internal code execution pattern and temperature, also have
an impact on the current consumption.
3: For RC oscillator configurations, current through REXT is not included. The current through the resistor can
be extended by the formula IR = VDD/2REXT (mA) with REXT in kΩ.
DS41291F-page 248
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.3
DC Characteristics: PIC16F883/884/886/887-I (Industrial)
DC CHARACTERISTICS
Param
No.
D020
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
Conditions
Device Characteristics
Power-down Base
Current(IPD)(2)
D021
Min.
Typ†
Max.
Units
VDD
Note
WDT, BOR, Comparators, VREF and
T1OSC disabled
—
0.05
1.2
μA
2.0
—
0.15
1.5
μA
3.0
—
0.35
1.8
μA
5.0
—
150
500
nA
3.0
-40°C ≤ TA ≤ +25°C
—
1.0
2.2
μA
2.0
WDT Current(1)
—
2.0
4.0
μA
3.0
—
3.0
7.0
μA
5.0
D022
—
42
60
μA
3.0
—
85
122
μA
5.0
D023
—
32
45
μA
2.0
D024
D025*
D026
—
60
78
μA
3.0
—
120
160
μA
5.0
—
30
36
μA
2.0
—
45
55
μA
3.0
—
75
95
μA
5.0
—
39
47
μA
2.0
—
59
72
μA
3.0
—
98
124
μA
5.0
—
2.0
5.0
μA
2.0
—
2.5
5.5
μA
3.0
BOR Current(1)
Comparator Current(1), both
comparators enabled
CVREF Current(1) (high range)
CVREF Current(1) (low range)
T1OSC Current(1), 32.768 kHz
—
3.0
7.0
μA
5.0
D027
—
0.30
1.6
μA
3.0
—
0.36
1.9
μA
5.0
A/D Current(1), no conversion in
progress
D028
—
90
125
μA
3.0
VP6 Reference Current
—
125
162
μA
5.0
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: The peripheral current is the sum of the base IDD or IPD and the additional current consumed when this
peripheral is enabled. The peripheral Δ current can be determined by subtracting the base IDD or IPD
current from this limit. Max values should be used when calculating total current consumption.
2: 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.
© 2009 Microchip Technology Inc.
DS41291F-page 249
PIC16F882/883/884/886/887
17.4
DC Characteristics: PIC16F883/884/886/887-E (Extended)
DC CHARACTERISTICS
Param
No.
D020E
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C for extended
Conditions
Device Characteristics
Power-down Base
Current (IPD)(2)
D021E
D022E
D023E
D024E
D025E*
D026E
D027E
D028E
Min.
Typ†
Max.
Units
VDD
Note
WDT, BOR, Comparators, VREF and
T1OSC disabled
—
0.05
9
μA
2.0
—
0.15
11
μA
3.0
—
0.35
15
μA
5.0
—
1
28
μA
2.0
—
2
30
μA
3.0
—
3
35
μA
5.0
—
42
65
μA
3.0
—
85
127
μA
5.0
—
32
45
μA
2.0
—
60
78
μA
3.0
—
120
160
μA
5.0
—
30
70
μA
2.0
—
45
90
μA
3.0
—
75
120
μA
5.0
—
39
91
μA
2.0
—
59
117
μA
3.0
—
98
156
μA
5.0
—
3.5
18
μA
2.0
WDT Current(1)
BOR Current(1)
Comparator Current(1), both
comparators enabled
CVREF Current(1) (high range)
CVREF Current(1) (low range)
T1OSC Current(1), 32.768 kHz
—
4.0
21
μA
3.0
—
5.0
24
μA
5.0
—
0.30
12
μA
3.0
—
0.36
16
μA
5.0
A/D Current(1), no conversion in
progress
—
90
130
μA
3.0
VP6 Reference Current
—
125
170
μA
5.0
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: The peripheral current is the sum of the base IDD or IPD and the additional current consumed when this
peripheral is enabled. The peripheral Δ current can be determined by subtracting the base IDD or IPD
current from this limit. Max values should be used when calculating total current consumption.
2: 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.
DS41291F-page 250
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.5
DC Characteristics:
PIC16F883/884/886/887-I (Industrial)
PIC16F883/884/886/887-E (Extended)
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
DC CHARACTERISTICS
Param
No.
Sym.
VIL
Characteristic
Min.
Typ†
Max.
Units
Vss
Vss
Conditions
—
0.8
V
4.5V ≤ VDD ≤ 5.5V
—
0.15 VDD
V
2.0V ≤ VDD ≤ 4.5V
Vss
—
0.2 VDD
V
2.0V ≤ VDD ≤ 5.5V
Input Low Voltage
I/O Port:
D030
with TTL buffer
D030A
D031
with Schmitt Trigger buffer
(1)
D032
MCLR, OSC1 (RC mode)
VSS
—
0.2 VDD
V
D033
OSC1 (XT and LP modes)
VSS
—
0.3
V
OSC1 (HS mode)
VSS
—
0.3 VDD
V
2.0
—
VDD
V
4.5V ≤ VDD ≤ 5.5V
0.25 VDD + 0.8
—
VDD
V
2.0V ≤ VDD ≤ 4.5V
0.8 VDD
—
VDD
V
2.0V ≤ VDD ≤ 5.5V
0.8 VDD
—
VDD
V
1.6
—
VDD
V
D033A
VIH
Input High Voltage
I/O ports:
D040
—
with TTL buffer
D040A
D041
with Schmitt Trigger buffer
D042
MCLR
D043
OSC1 (XT and LP modes)
D043A
OSC1 (HS mode)
0.7 VDD
—
VDD
V
D043B
OSC1 (RC mode)
0.9 VDD
—
VDD
V
—
± 0.1
±1
μA
VSS ≤ VPIN ≤ VDD,
Pin at high-impedance
(Note 1)
(2)
Input Leakage Current
IIL
D060
I/O ports
D061
MCLR(3)
—
± 0.1
±5
μA
VSS ≤ VPIN ≤ VDD
D063
OSC1
—
± 0.1
±5
μA
VSS ≤ VPIN ≤ VDD, XT, HS and
LP oscillator configuration
IPUR
PORTB Weak Pull-up Current
50
250
400
μA
VDD = 5.0V, VPIN = VSS
VOL
Output Low Voltage(5)
—
—
0.6
V
IOL = 8.5 mA, VDD = 4.5V (Ind.)
VDD – 0.7
—
—
V
IOH = -3.0 mA, VDD = 4.5V (Ind.)
D070*
D080
I/O ports
VOH
D090
Output High Voltage(5)
I/O ports
*
†
Note 1:
2:
3:
4:
5:
These parameters are characterized but not tested.
Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended to use an external
clock in RC mode.
Negative current is defined as current sourced by the pin.
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.
See Section 10.3.1 “Using the Data EEPROM” for additional information.
Including OSC2 in CLKOUT mode.
© 2009 Microchip Technology Inc.
DS41291F-page 251
PIC16F882/883/884/886/887
17.5
DC Characteristics:
PIC16F883/884/886/887-I (Industrial)
PIC16F883/884/886/887-E (Extended) (Continued)
DC CHARACTERISTICS
Param
No.
Sym.
D100
IULP
Characteristic
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +85°C for industrial
-40°C ≤ TA ≤ +125°C for extended
Min.
Typ†
Max.
Units
—
200
—
nA
See Application Note AN879,
“Using the Microchip Ultra
Low-Power Wake-up Module”
(DS00879)
OSC2 pin
—
—
15
pF
In XT, HS and LP modes when
external clock is used to drive
OSC1
All I/O pins
—
—
50
pF
Ultra Low-Power Wake-Up
Current
Conditions
Capacitive Loading Specs on
Output Pins
D101*
COSC2
D101A* CIO
Data EEPROM Memory
-40°C ≤ TA ≤ +85°C
D120
ED
Byte Endurance
100K
1M
—
E/W
D120A
ED
Byte Endurance
10K
100K
—
E/W
D121
VDRW
VDD for Read/Write
VMIN
—
5.5
V
D122
TDEW
Erase/Write Cycle Time
—
5
6
D123
TRETD
Characteristic Retention
40
—
—
Year Provided no other specifications
are violated
D124
TREF
Number of Total Erase/Write
Cycles before Refresh(4)
1M
10M
—
E/W
-40°C ≤ TA ≤ +85°C
-40°C ≤ TA ≤ +85°C
+85°C ≤ TA ≤ +125°C
Using EECON1 to read/write
VMIN = Minimum operating
voltage
ms
Program Flash Memory
D130
EP
Cell Endurance
10K
100K
—
E/W
D130A
ED
Cell Endurance
1K
10K
—
E/W
D131
VPR
VDD for Read
VMIN
—
5.5
V
D132
VPEW
VDD for Row Erase/Write
V
VMIN
—
5.5
VDD for Bulk Erase Operations
4.5
—
5.5
V
ms
D133
TPEW
Erase/Write cycle time
—
2
2.5
D134
TRETD
Characteristic Retention
40
—
—
*
†
Note 1:
2:
3:
4:
5:
+85°C ≤ TA ≤ +125°C
VMIN = Minimum operating
voltage
Year Provided no other specifications
are violated
These parameters are characterized but not tested.
Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended to use an external
clock in RC mode.
Negative current is defined as current sourced by the pin.
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.
See Section 10.3.1 “Using the Data EEPROM” for additional information.
Including OSC2 in CLKOUT mode.
DS41291F-page 252
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.6
Thermal Considerations
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristic
Typ.
Units
TH01
θJA
Thermal Resistance
Junction to Ambient
47.2
24.4
45.8
60.2
80.2
89.4
29
C/W
C/W
C/W
C/W
C/W
C/W
C/W
TH02
θJC
Thermal Resistance
Junction to Case
24.7
20.0
14.5
29
23.8
23.9
20.0
150
—
—
C/W
C/W
C/W
C/W
C/W
C/W
C/W
C
W
W
TH03
TH04
TH05
TH06
TH07
Note 1:
2:
3:
Conditions
40-pin PDIP package
44-pin QFN package
44-pin TQFP package
28-pin PDIP package
28-pin SOIC package
28-pin SSOP package
28-pin QFN package
40-pin PDIP package
44-pin QFN package
44-pin TQFP package
28-pin PDIP package
28-pin SOIC package
28-pin SSOP package
28-pin QFN package
TJ
Junction Temperature
For derated power calculations
PD
Power Dissipation
PD = PINTERNAL + PI/O
PINTERNAL Internal Power Dissipation
PINTERNAL = IDD x VDD
(NOTE 1)
PI/O
I/O Power Dissipation
—
W
PI/O = Σ (IOL * VOL) + Σ (IOH * (VDD - VOH))
PDER
Derated Power
—
W
PDER = (TJ - TA)/θJA
(NOTE 2, 3)
IDD is current to run the chip alone without driving any load on the output pins.
TA = Ambient Temperature.
Maximum allowable power dissipation is the lower value of either the absolute maximum total power
dissipation or derated power (PDER).
© 2009 Microchip Technology Inc.
DS41291F-page 253
PIC16F882/883/884/886/887
17.7
Timing Parameter Symbology
The timing parameter symbols have been created with
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
FIGURE 17-3:
T
Time
osc
rd
rw
sc
ss
t0
t1
wr
OSC1
RD
RD or WR
SCK
SS
T0CKI
T1CKI
WR
P
R
V
Z
Period
Rise
Valid
High-impedance
LOAD CONDITIONS
Load Condition
Pin
CL
VSS
Legend: CL =
DS41291F-page 254
50 pF
for all pins
15 pF
for OSC2 output
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
17.8
AC Characteristics: PIC16F883/884/886/887 (Industrial, Extended)
FIGURE 17-4:
CLOCK TIMING
Q4
Q1
Q2
Q3
Q4
Q1
OSC1/CLKIN
OS02
OS04
OS04
OS03
OSC2/CLKOUT
(LP,XT,HS Modes)
OSC2/CLKOUT
(CLKOUT Mode)
TABLE 17-1:
CLOCK OSCILLATOR TIMING REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Param
No.
OS01
Sym.
FOSC
Characteristic
External CLKIN Frequency(1)
Oscillator Frequency(1)
OS02
TOSC
External CLKIN Period(1)
Oscillator Period(1)
OS03
OS04*
TCY
TosH,
TosL
Min.
Typ†
Max.
Units
DC
DC
DC
DC
—
0.1
1
DC
27
250
50
50
—
250
50
250
—
—
—
—
32.768
—
—
—
—
—
—
—
30.5
—
—
—
37
4
20
20
—
4
20
4
•
•
•
•
—
10,000
1,000
—
kHz
MHz
MHz
MHz
kHz
MHz
MHz
MHz
μs
ns
ns
ns
μs
ns
ns
ns
Conditions
LP Oscillator mode
XT Oscillator mode
HS Oscillator mode
EC Oscillator mode
LP Oscillator mode
XT Oscillator mode
HS Oscillator mode
RC Oscillator mode
LP Oscillator mode
XT Oscillator mode
HS Oscillator mode
EC Oscillator mode
LP Oscillator mode
XT Oscillator mode
HS Oscillator mode
RC Oscillator mode
Instruction Cycle Time(1)
External CLKIN High,
External CLKIN Low
200
TCY
DC
ns
TCY = 4/FOSC
2
—
—
μs
LP oscillator
100
—
—
ns
XT oscillator
20
—
—
ns
HS oscillator
OS05* TosR, External CLKIN Rise,
0
—
•
ns
LP oscillator
TosF
External CLKIN Fall
0
—
•
ns
XT oscillator
0
—
•
ns
HS oscillator
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and
are not tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period. 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 OSC1 pin. When an external clock input is used, the “max” cycle time limit is “DC” (no clock) for
all devices.
© 2009 Microchip Technology Inc.
DS41291F-page 255
PIC16F882/883/884/886/887
TABLE 17-2:
OSCILLATOR PARAMETERS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature
-40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristic
Freq.
Tolerance
Min.
Typ†
Max.
Units
Conditions
OS06
TWARM
Internal Oscillator Switch
when running(3)
—
—
—
2
TOSC
Slowest clock
OS07
TSC
Fail-Safe Sample Clock
Period(1)
—
—
21
—
ms
LFINTOSC/64
OS08
HFOSC
Internal Calibrated
HFINTOSC Frequency(2)
±1%
7.92
8.0
8.08
MHz
VDD = 3.5V, 25°C
±2%
7.84
8.0
8.16
MHz
2.5V ≤ VDD ≤ 5.5V,
0°C ≤ TA ≤ +85°C
±5%
7.60
8.0
8.40
MHz
2.0V ≤ VDD ≤ 5.5V,
-40°C ≤ TA ≤ +85°C (Ind.),
-40°C ≤ TA ≤ +125°C (Ext.)
—
15
31
45
kHz
OS09*
LFOSC
Internal Uncalibrated
LFINTOSC Frequency
OS10*
TIOSC
HFINTOSC Oscillator
Wake-up from Sleep
Start-up Time
ST
—
5.5
12
24
μs
VDD = 2.0V, -40°C to +85°C
—
3.5
7
14
μs
VDD = 3.0V, -40°C to +85°C
—
3
6
11
μs
VDD = 5.0V, -40°C to +85°C
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period. 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 pin. When an external clock input is used, the “max” cycle time limit is “DC” (no clock)
for all devices.
2: To ensure these oscillator frequency tolerances, VDD and VSS must be capacitively decoupled as close to the
device as possible. 0.1 μF and 0.01 μF values in parallel are recommended.
3: By design.
DS41291F-page 256
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 17-5:
CLKOUT AND I/O TIMING
Cycle
Write
Fetch
Read
Execute
Q4
Q1
Q2
Q3
FOSC
OS12
OS11
OS20
OS21
CLKOUT
OS19
OS18
OS16
OS13
OS17
I/O pin
(Input)
OS14
OS15
I/O pin
(Output)
New Value
Old Value
OS18, OS19
TABLE 17-3:
CLKOUT AND I/O TIMING PARAMETERS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature -40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristic
Min.
Typ† Max. Units
Conditions
TOSH2CKL
FOSC↑ to CLKOUT↓ (1)
—
—
70
ns
VDD = 5.0V
OS12
TOSH2CKH
FOSC↑ to CLKOUT↑
—
—
72
ns
VDD = 5.0V
OS13
TCKL2IOV
CLKOUT↓ to Port out valid(1)
—
—
20
ns
OS14
TIOV2CKH
Port input valid before CLKOUT↑(1)
TOSC + 200 ns
—
—
ns
OS15*
TOSH2IOV
FOSC↑ (Q1 cycle) to Port out valid
—
50
70
ns
VDD = 5.0V
OS16
TOSH2IOI
FOSC↑ (Q2 cycle) to Port input invalid
(I/O in hold time)
50
—
—
ns
VDD = 5.0V
OS17
TIOV2OSH
Port input valid to FOSC↑ (Q2 cycle)
(I/O in setup time)
20
—
—
ns
OS18
TIOR
Port output rise time(2)
—
—
15
40
72
32
ns
VDD = 2.0V
VDD = 5.0V
OS19
TIOF
Port output fall time(2)
—
—
28
15
55
30
ns
VDD = 2.0V
VDD = 5.0V
OS20*
TINP
INT pin input high or low time
25
—
—
ns
OS21*
TRAP
PORTA interrupt-on-change new input
level time
TCY
—
—
ns
OS11
*
†
Note 1:
2:
(1)
These parameters are characterized but not tested.
Data in “Typ” column is at 5.0V, 25°C unless otherwise stated.
Measurements are taken in RC mode where CLKOUT output is 4 x TOSC.
Includes OSC2 in CLKOUT mode.
© 2009 Microchip Technology Inc.
DS41291F-page 257
PIC16F882/883/884/886/887
FIGURE 17-6:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND
POWER-UP TIMER TIMING
VDD
MCLR
30
Internal
POR
33
PWRT
Time-out
32
OSC
Start-Up Time
Internal Reset(1)
Watchdog Timer
Reset(1)
31
34
34
I/O pins
Note 1:
Asserted low.
FIGURE 17-7:
BROWN-OUT RESET TIMING AND CHARACTERISTICS
VDD
VBOR + VHYST
VBOR
(Device in Brown-out Reset)
(Device not in Brown-out Reset)
37
Reset
(due to BOR)
*
33*
64 ms delay only if PWRTE bit in the Configuration Word Register 1 is programmed to ‘0’.
DS41291F-page 258
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 17-4:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER
AND BROWN-OUT RESET PARAMETERS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature -40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristic
Min.
Typ†
Max. Units
Conditions
30
TMCL
MCLR Pulse Width (low)
2
5
—
—
—
—
μs
μs
VDD = 5V, -40°C to +85°C
VDD = 5V
31
TWDT
Watchdog Timer Time-out
Period (No Prescaler)
10
10
16
16
29
31
ms
ms
VDD = 5V, -40°C to +85°C
VDD = 5V
32
TOST
Oscillation Start-up Timer
Period(1, 2)
—
1024
—
33*
TPWRT
Power-up Timer Period
40
65
140
ms
34*
TIOZ
I/O High-impedance from
MCLR Low or Watchdog Timer
Reset
—
—
2.0
μs
35
VBOR
Brown-out Reset Voltage
2.0
—
2.2
V
BOR4V bit = 0 (NOTE 4)
3.6
4.0
4.4
V
BOR4V bit = 1, -40°C to +85°C
(NOTE 4)
3.6
4.0
4.5
V
BOR4V bit = 1, -40°C to +125°C
(NOTE 4)
—
50
—
mV
100
—
—
μs
36*
VHYST
Brown-out Reset Hysteresis
37*
TBOR
Brown-out Reset Minimum
Detection Period
TOSC (NOTE 3)
VDD ≤ VBOR
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: Instruction cycle period (TCY) equals four times the input oscillator time base period. 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 pin. When an external clock input is used, the “max” cycle time
limit is “DC” (no clock) for all devices.
2: By design.
3: Period of the slower clock.
4: To ensure these voltage tolerances, VDD and VSS must be capacitively decoupled as close to the device as
possible. 0.1 μF and 0.01 μF values in parallel are recommended.
© 2009 Microchip Technology Inc.
DS41291F-page 259
PIC16F882/883/884/886/887
FIGURE 17-8:
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
T0CKI
40
41
42
T1CKI
45
46
49
47
TMR0 or
TMR1
TABLE 17-5:
TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature
-40°C ≤ TA ≤ +125°C
Param
No.
40*
Sym.
TT0H
Characteristic
T0CKI High Pulse Width
No Prescaler
With Prescaler
41*
TT0L
T0CKI Low Pulse Width
No Prescaler
42*
TT0P
T0CKI Period
45*
TT1H
T1CKI High Synchronous, No Prescaler
Time
Synchronous,
with Prescaler
With Prescaler
Asynchronous
46*
TT1L
T1CKI Low
Time
Synchronous, No Prescaler
Synchronous,
with Prescaler
Asynchronous
47*
TT1P
T1CKI Input Synchronous
Period
48
FT1
Timer1 Oscillator Input Frequency Range
(oscillator enabled by setting bit T1OSCEN)
49*
TCKEZTMR1 Delay from External Clock Edge to Timer
Increment
Asynchronous
*
†
Min.
Typ†
Max.
Units
0.5 TCY + 20
—
—
ns
10
—
—
ns
0.5 TCY + 20
—
—
ns
10
—
—
ns
Greater of:
20 or TCY + 40
N
—
—
ns
0.5 TCY + 20
—
—
ns
15
—
—
ns
30
—
—
ns
0.5 TCY + 20
—
—
ns
15
—
—
ns
30
—
—
ns
Greater of:
30 or TCY + 40
N
—
—
ns
60
—
—
ns
—
32.768
—
kHz
2 TOSC
—
7 TOSC
—
Conditions
N = prescale value
(2, 4, ..., 256)
N = prescale value
(1, 2, 4, 8)
Timers in Sync
mode
These parameters are characterized but not tested.
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not
tested.
DS41291F-page 260
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 17-9:
CAPTURE/COMPARE/PWM TIMINGS (ECCP)
CCP1
(Capture mode)
CC01
CC02
CC03
Note:
TABLE 17-6:
Refer to Figure 17-3 for load conditions.
CAPTURE/COMPARE/PWM REQUIREMENTS (ECCP)
Standard Operating Conditions (unless otherwise stated)
Operating Temperature -40°C ≤ TA ≤ +125°C
Param
No.
CC01*
CC02*
CC03*
Sym.
TccL
TccH
TccP
Characteristic
CCP1 Input Low Time
CCP1 Input High Time
CCP1 Input Period
Min.
Typ†
Max.
Units
No Prescaler
0.5TCY + 20
—
—
ns
With Prescaler
20
—
—
ns
No Prescaler
0.5TCY + 20
—
—
ns
With Prescaler
20
—
—
ns
3TCY + 40
N
—
—
ns
Conditions
N = prescale
value (1, 4 or
16)
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
© 2009 Microchip Technology Inc.
DS41291F-page 261
PIC16F882/883/884/886/887
TABLE 17-7:
COMPARATOR SPECIFICATIONS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature -40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristics
CM01
VOS
Input Offset Voltage
CM02
VCM
Input Common Mode Voltage
CM03* CMRR
Common Mode Rejection Ratio
CM04* TRT
Response Time
Min.
Typ†
Max.
Units
—
± 5.0
± 10
mV
0
—
VDD - 1.5
V
+55
—
—
dB
Falling
—
150
600
ns
Rising
—
200
1000
ns
—
—
10
μs
CM05* TMC2COV Comparator Mode Change to
Output Valid
Comments
(VDD - 1.5)/2
(NOTE 1)
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: Response time is measured with one comparator input at (VDD - 1.5)/2 - 100 mV to (VDD - 1.5)/2 + 20 mV.
TABLE 17-8:
COMPARATOR VOLTAGE REFERENCE (CVREF) SPECIFICATIONS
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Param
No.
Sym.
Characteristics
Min.
Typ†
Max.
Units
Comments
CV01*
CLSB
Step Size(2)
—
—
VDD/24
VDD/32
—
—
V
V
Low Range (VRR = 1)
High Range (VRR = 0)
CV02*
CACC
Absolute Accuracy
—
—
—
—
± 1/2
± 1/2
LSb
LSb
Low Range (VRR = 1)
High Range (VRR = 0)
CV03*
CR
Unit Resistor Value (R)
—
2k
—
Ω
CV04*
CST
Settling Time(1)
—
—
10
μs
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
Note 1: Settling time measured while VRR = 1 and VR<3:0> transitions from ‘0000’ to ‘1111’.
2: See Section 8.10 “Comparator Voltage Reference” for more information.
TABLE 17-9:
VOLTAGE (VR) REFERENCE SPECIFICATIONS
VR Voltage Reference Specifications
Param
No.
Symbol
Characteristics
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Min.
Typ.
Max.
Units
VR01
VROUT
VR voltage output
0.5
0.6
0.7
V
VR02*
TSTABLE
Settling Time
—
10
100*
μs
*
Comments
These parameters are characterized but not tested.
DS41291F-page 262
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 17-10: PIC16F883/884/886/887 A/D CONVERTER (ADC) CHARACTERISTICS
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Param
Sym.
No.
Characteristic
Min.
Typ†
Max.
Units
Conditions
AD01
NR
Resolution
—
—
10 bits
AD02
EIL
Integral Error
—
—
±1
LSb VREF = 5.12V
AD03
EDL
Differential Error
—
—
±1
LSb No missing codes to 10 bits
VREF = 5.12V
AD04
EOFF
Offset Error
0
+1.5
+3.0
LSb VREF = 5.12V
AD07
EGN
LSb VREF = 5.12V
bit
Gain Error
—
—
±1
AD06 VREF
AD06A
Reference Voltage(3)
2.2
2.7
—
—
VDD
V
AD07
VAIN
Full-Scale Range
VSS
—
VREF
V
AD08
ZAIN
Recommended
Impedance of Analog
Voltage Source
—
—
10
kΩ
AD09* IREF
VREF Input Current(3)
10
—
1000
μA
During VAIN acquisition.
Based on differential of VHOLD to VAIN.
—
—
50
μA
During A/D conversion cycle.
Absolute minimum to ensure 1 LSb
accuracy
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: Total Absolute Error includes integral, differential, offset and gain errors.
2: The A/D conversion result never decreases with an increase in the input voltage and has no missing
codes.
3: ADC VREF is from external VREF or VDD pin, whichever is selected as reference input.
4: When ADC is off, it will not consume any current other than leakage current. The power-down current
specification includes any such leakage from the ADC module.
© 2009 Microchip Technology Inc.
DS41291F-page 263
PIC16F882/883/884/886/887
TABLE 17-11: PIC16F883/884/886/887 A/D CONVERSION REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating temperature
-40°C ≤ TA ≤ +125°C
Param
Sym.
No.
AD130* TAD
Characteristic
A/D Clock Period
A/D Internal RC
Oscillator Period
AD131 TCNV
Conversion Time
(not including
Acquisition Time)(1)
Min.
Typ†
1.6
—
9.0
μs
TOSC-based, VREF ≥ 3.0V
3.0
—
9.0
μs
TOSC-based, VREF full range
3.0
6.0
9.0
μs
ADCS<1:0> = 11 (ADRC mode)
At VDD = 2.5V
1.6
4.0
6.0
μs
At VDD = 5.0V
—
11
—
TAD
Set GO/DONE bit to new data in A/D
Result register
11.5
—
μs
Amplifier Settling Time
—
—
5
μs
Q4 to A/D Clock Start
—
TOSC/2
—
—
—
TOSC/2 + TCY
—
—
AD132* TACQ Acquisition Time
AD133*
TAMP
AD134 TGO
Max. Units
Conditions
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.
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
Note 1: ADRESH and ADRESL registers may be read on the following TCY cycle.
2: See Section 9.3 “A/D Acquisition Requirements” for minimum conditions.
DS41291F-page 264
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 17-10:
PIC16F883/884/886/887 A/D CONVERSION TIMING (NORMAL MODE)
BSF ADCON0, GO
AD134
1 TCY
(TOSC/2(1))
AD131
Q4
AD130
A/D CLK
9
A/D Data
8
7
6
3
2
1
0
NEW_DATA
OLD_DATA
ADRES
1 TCY
ADIF
GO
DONE
Note 1:
Sampling Stopped
AD132
Sample
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.
FIGURE 17-11:
PIC16F883/884/886/887 A/D CONVERSION TIMING (SLEEP MODE)
BSF ADCON0, GO
AD134
(TOSC/2 + TCY(1))
1 TCY
AD131
Q4
AD130
A/D CLK
9
A/D Data
8
7
6
OLD_DATA
ADRES
3
2
1
0
NEW_DATA
ADIF
1 TCY
GO
DONE
Sample
Note 1:
AD132
Sampling Stopped
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.
© 2009 Microchip Technology Inc.
DS41291F-page 265
PIC16F882/883/884/886/887
FIGURE 17-12:
EUSART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK
pin
121
121
RC7/RX/DT
pin
120
Note:
122
Refer to Figure 17-3 for load conditions.
TABLE 17-12: EUSART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature
-40°C ≤ TA ≤ +125°C
Param.
No.
120
121
122
Symbol
Characteristic
TCKH2DTV SYNC XMIT (Master & Slave)
Clock high to data-out valid
TCKRF
Clock out rise time and fall time (Master mode)
TDTRF
Data-out rise time and fall time
FIGURE 17-13:
Min.
Max.
Units
—
40
ns
—
—
20
20
ns
ns
Conditions
EUSART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK
pin
RC7/RX/DT
pin
125
126
Note: Refer to Figure 17-3 for load conditions.
TABLE 17-13: EUSART SYNCHRONOUS RECEIVE REQUIREMENTS
Standard Operating Conditions (unless otherwise stated)
Operating Temperature -40°C ≤ TA ≤ +125°C
Param.
No.
125
126
Symbol
Characteristic
TDTV2CKL SYNC RCV (Master & Slave)
Data-hold before CK ↓ (DT hold time)
TCKL2DTL
DS41291F-page 266
Data-hold after CK ↓ (DT hold time)
Min.
Max.
Units
10
—
ns
15
—
ns
Conditions
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 17-14:
SPI MASTER MODE TIMING (CKE = 0, SMP = 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 17-3 for load conditions.
FIGURE 17-15:
SPI MASTER MODE TIMING (CKE = 1, SMP = 1)
SS
81
SCK
(CKP = 0)
71
72
79
73
SCK
(CKP = 1)
80
78
SDO
MSb
bit 6 - - - - - -1
LSb
75, 76
SDI
MSb In
bit 6 - - - -1
LSb In
74
73
Note: Refer to Figure 17-3 for load conditions.
© 2009 Microchip Technology Inc.
DS41291F-page 267
PIC16F882/883/884/886/887
FIGURE 17-16:
SPI SLAVE MODE TIMING (CKE = 0)
SS
70
SCK
(CKP = 0)
83
71
72
78
79
79
78
SCK
(CKP = 1)
80
MSb
SDO
LSb
bit 6 - - - - - -1
77
75, 76
SDI
MSb In
bit 6 - - - -1
LSb In
74
73
Note: Refer to Figure 17-3 for load conditions.
FIGURE 17-17:
SPI SLAVE MODE TIMING (CKE = 1)
82
SS
SCK
(CKP = 0)
70
83
71
72
SCK
(CKP = 1)
80
SDO
MSb
bit 6 - - - - - -1
LSb
75, 76
SDI
MSb In
77
bit 6 - - - -1
LSb In
74
Note: Refer to Figure 17-3 for load conditions.
DS41291F-page 268
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 17-14: SPI MODE REQUIREMENTS
Param
No.
Symbol
70*
Characteristic
TSSL2SCH, SS↓ to SCK↓ or SCK↑ input
TSSL2SCL
Min.
Typ†
Max. Units Conditions
TCY
—
—
ns
71*
TSCH
SCK input high time (Slave mode)
TCY + 20
—
—
ns
72*
TSCL
SCK input low time (Slave mode)
TCY + 20
—
—
ns
73*
TDIV2SCH, Setup time of SDI data input to SCK edge
TDIV2SCL
100
—
—
ns
74*
TSCH2DIL,
TSCL2DIL
Hold time of SDI data input to SCK edge
100
—
—
ns
75*
TDOR
SDO data output rise time
—
10
25
ns
76*
TDOF
SDO data output fall time
3.0-5.5V
2.0-5.5V
—
25
50
ns
—
10
25
ns
77*
TSSH2DOZ
SS↑ to SDO output high-impedance
10
—
50
ns
78*
TSCR
SCK output rise time
(Master mode)
3.0-5.5V
—
10
25
ns
2.0-5.5V
—
25
50
ns
79*
TSCF
SCK output fall time (Master mode)
—
10
25
ns
80*
TSCH2DOV, SDO data output valid after
TSCL2DOV SCK edge
3.0-5.5V
—
—
50
ns
2.0-5.5V
—
—
145
ns
81*
TDOV2SCH, SDO data output setup to SCK edge
TDOV2SCL
Tcy
—
—
ns
82*
TSSL2DOV
—
—
50
ns
83*
TSCH2SSH, SS ↑ after SCK edge
TSCL2SSH
1.5TCY + 40
—
—
ns
SDO data output valid after SS↓ edge
* These parameters are characterized but not tested.
† Data in “Typ” column is at 5.0V, 25°C unless otherwise stated. These parameters are for design guidance
only and are not tested.
FIGURE 17-18:
I2C™ BUS START/STOP BITS TIMING
SCL
91
90
93
92
SDA
Start
Condition
Stop
Condition
Note: Refer to Figure 17-3 for load conditions.
© 2009 Microchip Technology Inc.
DS41291F-page 269
PIC16F882/883/884/886/887
TABLE 17-15: I2C™ BUS START/STOP BITS REQUIREMENTS
Param
No.
Symbol
90*
TSU:STA
91*
THD:STA
92*
TSU:STO
93
THD:STO Stop condition
Characteristic
Start condition
100 kHz mode
4700
Typ. Max. Units
—
—
Setup time
400 kHz mode
600
—
—
Start condition
100 kHz mode
4000
—
—
Hold time
400 kHz mode
600
—
—
Stop condition
100 kHz mode
4700
—
—
Setup time
Hold time
*
Min.
400 kHz mode
600
—
—
100 kHz mode
4000
—
—
400 kHz mode
600
—
—
Conditions
ns
Only relevant for Repeated
Start condition
ns
After this period, the first
clock pulse is generated
ns
ns
These parameters are characterized but not tested.
FIGURE 17-19:
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 17-3 for load conditions.
DS41291F-page 270
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
TABLE 17-16: I2C™ BUS DATA REQUIREMENTS
Param.
No.
100*
Symbol
THIGH
Characteristic
Clock high time
Min.
Max.
Units
100 kHz mode
4.0
—
μs
Device must operate at a
minimum of 1.5 MHz
400 kHz mode
0.6
—
μs
Device must operate at a
minimum of 10 MHz
1.5TCY
—
100 kHz mode
4.7
—
μs
Device must operate at a
minimum of 1.5 MHz
400 kHz mode
1.3
—
μs
Device must operate at a
minimum of 10 MHz
SSP Module
101*
TLOW
Clock low time
SSP Module
102*
103*
90*
91*
106*
107*
92*
109*
110*
TR
TF
TSU:STA
THD:STA
THD:DAT
TSU:DAT
TSU:STO
TAA
TBUF
CB
*
Note 1:
2:
Conditions
1.5TCY
—
SDA and SCL rise
time
100 kHz mode
—
1000
ns
400 kHz mode
0.1CB
300
ns
SDA and SCL fall
time
100 kHz mode
—
300
ns
400 kHz mode
20 + 0.1CB
300
ns
CB is specified to be from
10-400 pF
Only relevant for
Repeated Start condition
20 +
100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
Start condition hold 100 kHz mode
time
400 kHz mode
4.0
—
μs
0.6
—
μs
Data input hold time 100 kHz mode
0
—
ns
400 kHz mode
0
0.9
μs
100 kHz mode
250
—
ns
400 kHz mode
100
—
ns
Start condition
setup time
Data input setup
time
Stop condition
setup time
Output valid from
clock
Bus free time
100 kHz mode
4.7
—
μs
400 kHz mode
0.6
—
μs
100 kHz mode
—
3500
ns
400 kHz mode
—
—
ns
100 kHz mode
4.7
—
μs
400 kHz mode
1.3
—
μs
—
400
pF
Bus capacitive loading
CB is specified to be from
10-400 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
These parameters are characterized but not tested.
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 (400 kHz) I2C bus device can be used in a Standard mode (100 kHz) 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.
© 2009 Microchip Technology Inc.
DS41291F-page 271
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 272
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
18.0
DC AND AC CHARACTERISTICS GRAPHS AND TABLES
The graphs and tables provided in this section are for design guidance and are not tested.
In some graphs or tables, the data presented are outside specified operating range (i.e., outside specified VDD
range). This is for information only and devices are ensured to operate properly only within the specified range.
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein are
not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore, outside the warranted range.
“Typical” represents the mean of the distribution at 25°C. “Maximum” or “minimum” represents
(mean + 3σ) or (mean - 3σ) respectively, where σ is a standard deviation, over each temperature range.
IDD (mA)
FIGURE 18-1:
TYPICAL I3V
DD vs. FOSC
DD (EC
Typical
2V
4V OVER V5V
EC Mode0.277
1Mhz
0.086
0.153
0.220
2Mhz
0.150
0.2596
0.3718
0.4681
4Mhz
0.279
0.472
0.675
0.850
4.0
6Mhz
0.382
0.635
0.903
1.135
8Mhz Typical: Statistical
0.486Mean @25°C
0.798
1.132
1.420
10Mhz Maximum: Mean
0.589
0.961
1.360
1.706
(Worst-case
Temp) + 3σ
3.5
12Mhz
0.696
1.126
1.596
2.005
(-40°C to 125°C)
14Mhz
0.802
1.291
1.832
2.304
16Mhz
0.908
1.457
2.068
2.603
3.0
18Mhz
1.017
1.602
2.268
2.848
20Mhz
1.126
1.748
2.469
3.093
2.5
Max
2.0
1Mhz
2Mhz
4Mhz
1.5
6Mhz
8Mhz
1.0
10Mhz
12Mhz
14Mhz
0.5
16Mhz
18Mhz
20Mhz
0.0
1 MHz
2V
0.168
0.261
0.449
0.577
0.705
0.833
0.956
1.078
1.201
1.305
1.409
2 MHz
3V
0.236
0.394
0.710
0.972
1.233
1.495
1.711
1.926
2.142
2.326
2.510
4 MHz
6 MHz
4V
0.315
0.537
0.981
1.331
1.682
2.032
2.372
2.713
3.054
3.295
3.536
8 MHz
5V
0.412
0.704
1.287
1.739
2.191
2.642
3.101
3.560
4.018
4.324
4.630
10 MHz
MODE)
5.5V
0.310
0.5236
0.951
1.269
1.587
1.905
2.241
2.577
2.913
3.185
3.458
5.5V
5V
4V
5.5V
0.452
0.780
1.435
1.950
2.465
2.979
3.506
4.032
4.558
4.887
12 MHz
3V
2V
14 MHz
16 MHz
18 MHz
20 MHz
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 273
PIC16F882/883/884/886/887
FIGURE 18-2:
MAXIMUM IDD vs. FOSC OVER VDD (EC MODE)
6.0
5.0
5.5V
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
5V
4.0
IDD (mA)
4V
3.0
3V
2.0
2V
1.0
0.0
1 MHz
2 MHz
4 MHz
6 MHz
8 MHz
10 MHz
12 MHz
14 MHz
16 MHz
18 MHz
20 MHz
VDD (V)
FIGURE 18-3:
TYPICAL IDD vs. FOSC OVER VDD (HS MODE)
HS Mode
5.0
4.5
4.0
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
5.5V
5V
4.5V
IDD (mA)
3.5
3.0
2.5
2.0
1.5
1.0
3V
3.5V
4V
4.5V
5V
5.5V
0.567660978 0.6909750.8211857610.9883470541.0462473761.119615457
1.1610564131.4069334781.6664380432.0030751092.1193190652.268818804
4V 2.883088587 3.03554863
3.23775
3.5V 3.74139 3.967407543
3V
0.5
0.0
4 MHz
10 MHz
16 MHz
20 Mhz
FOSC
DS41291F-page 274
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-4:
MAXIMUM IDD vs. FOSC OVER
VDD (HS MODE)
HS Mode
5.5
5.0
4.5
4.0
5.5V
5V
4.5V
Typical:
Mean @25°C4V
3V Statistical 3.5V
4.5V
5V
5.5V
Maximum:
Mean (Worst-case Temp) + 3σ
0.8868608641.0693043161.2645617521.4868166111.5076394231.520959608
(-40°C1.6176371031.9623642592.3355493582.7630868222.8139211682.849632041
to 125°C)
3.8375797553.9157601913.967889512
4.685048474 4.78069621
IDD (mA)
3.5
3.0
2.5
4V
2.0
3.5V
3V
1.5
1.0
0.5
0.0
4 MHz
10 MHz
16 MHz
20 MHz
FOSC
TYPICAL IDD vs. VDD OVER FOSC (XT MODE)
FIGURE 18-5:
XT Mode
1,200
2
1,000
2.5
3
Typical: Statistical Mean @25×C
180.1774 235.0683 289.9592
Maximum: Mean (Worst Case Temp) + 3
382.484 481.2347
(-40×C to283.7333
125×C)
3.5
4
4.5
5
5.5
Typical: Statistical Mean @25°C
337.753 385.547 436.866 488.184 554.8964
Maximum: Mean (Worst-case Temp)577.923
+ 3σ 674.6106 783.831 893.052 1033.15
(-40°C to 125°C)
Vdd
2
2.5
3
3.5
4
4.5
5
5.5
244.8837 320.7132 396.5426 461.707 526.8719 587.642 648.412 724.0755
375.529 522.3721 669.2152 822.619 976.0232 1163.67 1351.32
IDD (uA)
800
4 MHz
600
400
1 MHz
200
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 275
PIC16F882/883/884/886/887
FIGURE 18-6:
MAXIMUM IDD vs. VDD OVER FOSC (XT MODE)
XT Mode
1,800
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
1,600
1,400
IDD (uA)
1,200
1,000
4 MHz
800
600
1 MHz
400
200
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
4.5
5.0
5.5
VDD (V)
TYPICAL IDD vs. VDD OVER FOSC (EXTRC MODE)
FIGURE 18-7:
(EXTRC Mode)
1,800
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
1,600
1,400
IDD (uA)
1,200
4 Mhz
1,000
800
1 Mhz
600
400
200
0
2.0
2.5
3.0
3.5
4.0
VDD (V)
DS41291F-page 276
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-8:
MAXIMUM IDD vs. VDD (EXTRC MODE)
2,000
Typical:
Typical:Statistical
StatisticalMean
[email protected]°C
@25×C
Maximum:Mean
Mean(Worst-case
(Worst CaseTemp)
Temp)+ +3σ3
Maximum:
(-40×C to 125×C)
(-40°C to 125°C)
1,800
1,600
1,400
4 Mhz
IDD (uA)
1,200
1,000
800
1 Mhz
600
400
200
0
2.0
2.5
3.0
4.0
3.5
4.5
5.0
5.5
VDD (V)
FIGURE 18-9:
IDD vs. VDD OVER FOSC (LFINTOSC MODE, 31 kHz)
LFINTOSC Mode, 31KHZ
80
70
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
60
IDD (μA)
50
Maximum
40
30
Typical
20
10
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 277
PIC16F882/883/884/886/887
FIGURE 18-10:
IDD vs. VDD (LP MODE)
80
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
70
IDD (uA)
60
50
32 kHz Maximum
40
30
32 kHz Typical
20
10
0
2.0
3.0
2.5
4.0
3.5
4.5
5.0
5.5
VDD (V)
FIGURE 18-11:
TYPICAL IDD vs. FOSC OVER VDD (HFINTOSC MODE)
4V
2,500
IDD (uA)
2,000
HFINTOSC
5V
5.5V
197.9192604299.82617395.019 496.999 574.901
210.9124688
324.4079 431.721 544.182 620.66
Typical:Statistical
Statistical
[email protected]°C
@25×C
Typical:
Mean
Maximum: Mean
(Worst Case Temp) + 3
239.9707708369.77809491.538
623.314 717.723
Maximum:
Mean
(Worst-case
Temp) + 3σ
(-40×C to 125×C)
298.6634479460.30461619.714 793.635 901.409
(-40°C to 125°C)
414.3997292639.99889 878.13 1127.53 1275.6
649.86985881014.40021421.21 1858.97 2097.71
5.5V
5V
1,500
4V
3V
1,000
2V
500
2V
3V
4V
5V
5.5V
0
125 kHz
25 kHz
500 kHz
1 MHz
2 MHz
4 MHz
8 MHz
VDD (V)
DS41291F-page 278
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-12:
MAXIMUM IDD vs. FOSC OVER VDD (HFINTOSC MODE)
HFINTOSC
3,000
2,500
5.5V
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
5V
IDD (uA)
2,000
4V
1,500
3V
1,000
2V
500
0
125 kHz
250 kHz
500 kHz
1 MHz
2 MHz
4 MHz
8 MHz
VDD (V)
FIGURE 18-13:
TYPICAL IPD vs. VDD (SLEEP MODE, ALL PERIPHERALS DISABLED)
Typical
(Sleep Mode all Peripherals Disabled)
0.45
0.40
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
0.35
IPD (uA)
0.30
0.25
0.20
0.15
0.10
0.05
0.00
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 279
PIC16F882/883/884/886/887
FIGURE 18-14:
MAXIMUM IPD vs. VDD (SLEEP MODE, ALL PERIPHERALS DISABLED)
Maximum
(Sleep Mode all Peripherals Disabled)
18
16
Typical: Statistical Mean @25°C
Maximum:
Mean +
3σ
Maximum: Mean
(Worst-case
Temp) + 3σ
(-40°C to 125°C)
14
Max. 125°C
IPD (μA)
12
10
8
6
4
Max. 85°C
2
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-15:
COMPARATOR IPD vs. VDD (BOTH COMPARATORS ENABLED)
180
160
140
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
120
IPD (uA)
Maximum
100
80
Typical
60
Typical Max
31.9 40 43.9
45.6
60.8
59.3 20 77.7
73.0
95.8
86.7 113.8
0
100.4 131.8
114.1 149.9 2.0
127.7
DS41291F-page 280
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-16:
BOR IPD vs. VDD OVER TEMPERATURE
160
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
140
120
IPD (μA)
100
Maximum
80
Typical
60
40
20
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-17:
TYPICAL WDT IPD vs. VDD (25°C)
3.0
2.5
IPD (uA)
2.0
1.5
Typical:Typical
Statistical Mean
@25°C Max 125×C
Max 85×C
2 1.007
2.140
27.702
2.5 1.146
2.711
29.079
3 1.285
3.282
30.08
3.5 1.449
3.899
31.347
4 1.612
4.515
32.238
4.5 1.924
5.401
33.129
5 2.237
6.288
34.02
5.5 2.764
7.776
1.0
0.5
0.0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 281
PIC16F882/883/884/886/887
FIGURE 18-18:
MAXIMUM WDT IPD vs. VDD OVER TEMPERATURE
40.0
Maximum:
Mean
+3
Maximum:
Mean
+ 3σ
35.0
Max. 125°C
30.0
IPD (uA)
25.0
20.0
15.0
10.0
Max. 85°C
5.0
0.0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-19:
WDT PERIOD vs. VDD OVER TEMPERATURE
WDT Time-out Period
32
30
Maximum: Mean + 3σ (-40°C to 125°C)
28
Max. (125°C)
26
Max. (85°C)
Time (ms)
24
22
20
Typical
18
16
14
Minimum
12
10
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS41291F-page 282
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-20:
WDT PERIOD vs. TEMPERATURE (VDD = 5.0V)
Vdd = 5V
30
28
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
26
Maximum
Time (ms)
24
22
20
Typical
18
16
Minimum
14
12
10
-40°C
25°C
85°C
125°C
Temperature (°C)
FIGURE 18-21:
CVREF IPD vs. VDD OVER TEMPERATURE (HIGH RANGE)
High Range
IPD (uA)
140 Max 85×C Max 125×C
35.8
68.0 Mean @25°C
Typical:
Statistical
44.8
77.3 (Worst-case Temp) + 3σ
Maximum:
Mean
53.8
86.5
120
(-40°C to 125°C)
62.8
94.3
71.8
102.1
81.0
109.8
100
Max. 125°C
90.1
117.6
99.2
125.1
80
Max. 85°C
60
Typical
40
20
Max 85×C Max 125×C
46.5
86.4
58.3
98.1
70.0
109.9
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 283
PIC16F882/883/884/886/887
FIGURE 18-22:
CVREF IPD vs. VDD OVER TEMPERATURE (LOW RANGE)
low Range
180
160
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
140
Max. 125°C
IPD (uA)
120
100
Max. 85°C
80
Typical
60
40
20
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
4.5
5.0
5.5
VDD (V)
FIGURE 18-23:
TYPICAL VP6 REFERENCE IPD vs. VDD (25°C)
VP6 Reference IPD vs. VDD (25×C)
160
140
120
IPD (uA)
100
Typical
80
60
40
20
0
2.0
2.5
3.0
3.5
4.0
VDD (V)
DS41291F-page 284
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-24:
MAXIMUM VP6 REFERENCE IPD vs. VDD OVER TEMPERATURE
Max VP6 Reference IPD vs. VDD Over Temperature
180
160
140
Max 125°C
IPD (uA)
120
Max 85°C
100
80
60
40
20
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
5.0
5.5
VDD (V)
FIGURE 18-25:
T1OSC IPD vs. VDD OVER TEMPERATURE (32 kHz)
30
25
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
Max. 125°C
IPD (uA)
20
15
10
5
2
2.5
3
3.5
4
4.5
5
5.5
Typ 25×C
2.022
2.247
2.472
2.453
2.433
2.711
2.989
3.112
Max 85×C
4.98
5.23
5.49
5.79
6.08
6.54
7.00
7.34
Max 125×C
17.54
19.02
20.29
21.50
Max. 85°C
22.45
23.30
24.00
Typ. 25°C
0
2.0
2.5
3.0
3.5
4.0
4.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 285
PIC16F882/883/884/886/887
FIGURE 18-26:
VOL vs. IOL OVER TEMPERATURE (VDD = 3.0V)
(VDD = 3V, -40×C TO 125×C)
0.8
0.7
Typical: Statistical Mean @25°C
Maximum: Mean + 3σ
Max. 125°C
0.6
VOL (V)
0.5
Max. 85°C
0.4
Typical 25°C
0.3
0.2
Min. -40°C
0.1
0.0
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
IOL (mA)
VOL vs. IOL OVER TEMPERATURE (VDD = 5.0V)
FIGURE 18-27:
0.45
Typical: Statistical Mean @25°C
Typical:
Statistical
Maximum:
Mean
+ 3σ Mean
Maximum: Means + 3
0.40
Max. 125°C
0.35
Max. 85°C
VOL (V)
0.30
0.25
Typ. 25°C
0.20
0.15
Min. -40°C
0.10
0.05
0.00
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
IOL (mA)
DS41291F-page 286
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-28:
VOH vs. IOH OVER TEMPERATURE (VDD = 3.0V)
3.5
3.0
Max. -40°C
Typ. 25°C
2.5
Min. 125°C
VOH (V)
2.0
1.5
1.0
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
0.5
0.0
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
-4.0
IOH (mA)
FIGURE 18-29:
(VDD = 5.0V)
VOH vs. IOH OVER TEMPERATURE
(
,
)
5.5
5.0
Max. -40°C
Typ. 25°C
VOH (V)
4.5
Min. 125°C
4.0
3.5
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
3.0
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
-3.5
-4.0
-4.5
-5.0
IOH (mA)
© 2009 Microchip Technology Inc.
DS41291F-page 287
PIC16F882/883/884/886/887
FIGURE 18-30:
TTL INPUT THRESHOLD VIN vs. VDD OVER TEMPERATURE
(TTL Input, -40×C TO 125×C)
1.7
1.5
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
Max. -40°C
VIN (V)
1.3
Typ. 25°C
1.1
Min. 125°C
0.9
0.7
0.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-31:
SCHMITT TRIGGER INPUT THRESHOLD VIN vs. VDD OVER TEMPERATURE
(ST Input, -40×C TO 125×C)
4.0
VIH Max. 125°C
3.5
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
VIH Min. -40°C
VIN (V)
3.0
2.5
2.0
VIL Max. -40°C
1.5
VIL Min. 125°C
1.0
0.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS41291F-page 288
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-32:
4
5.5
COMPARATOR RESPONSE TIME (RISING EDGE)
200
278
639
846
V+ input 202
= VCM 531
140
V- input = Transition from VCM + 100MV to VCM - 20MV
1,000
900
800
Max. (125°C)
Response Time (nS)
700
600
Note:
500
VCM = VDD - 1.5V)/2
V+ input = VCM
V- input = Transition from VCM + 100MV to VCM - 20MV
Max. (85°C)
400
300
Typ. (25°C)
200
Min. (-40°C)
100
0
2.0
2.5
4.0
5.5
VDD (Volts)
FIGURE 18-33:
Vdd
COMPARATOR RESPONSE TIME (FALLING EDGE)
-40×C 25×C
85×C
125×C
2
279
327
547
557
600
2.5
226
267
425
440
4
172
204
304
319
5.5
119
142
182
Response Time (nS)
500
400
300
Max. (125°C)
Max. (85°C)
200
Note:
100
VCM = VDD - 1.5V)/2
V+ input = VCM
V- input = Transition from VCM - 100MV to VCM + 20MV
Typ. (25°C)
Min. (-40°C)
0
2.0
2.5
4.0
5.5
VDD (Volts)
© 2009 Microchip Technology Inc.
DS41291F-page 289
PIC16F882/883/884/886/887
FIGURE 18-34:
LFINTOSC FREQUENCY vs. VDD OVER TEMPERATURE (31 kHz)
LFINTOSC 31Khz
45,000
40,000
Max. -40°C
35,000
Typ. 25°C
Frequency (Hz)
30,000
25,000
20,000
Min. 85°C
Min. 125°C
15,000
10,000
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case) + 3σ
5,000
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-35:
ADC CLOCK PERIOD vs. VDD OVER TEMPERATURE
8
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
(-40°C to 125°C)
125°C
6
Time (μs)
85°C
4
25°C
-40°C
2
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS41291F-page 290
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-36:
TYPICAL HFINTOSC START-UP TIMES vs. VDD OVER TEMPERATURE
16
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case) + 3σ
14
85°C
12
25°C
Time (μs)
10
-40°C
8
6
4
2
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-37:
MAXIMUM HFINTOSC START-UP TIMES vs. VDD OVER TEMPERATURE
-40C to +85C
25
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case) + 3σ
Time (μs)
20
15
85°C
25°C
10
-40°C
5
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 291
PIC16F882/883/884/886/887
FIGURE 18-38:
MINIMUM HFINTOSC START-UP TIMES vs. VDD OVER TEMPERATURE
-40C to +85C
10
9
Typical: Statistical Mean @25°C
Maximum: Mean (Worst-case Temp) + 3σ
8
7
Time (μs)
85°C
6
25°C
5
-40°C
4
3
2
1
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-39:
TYPICAL HFINTOSC FREQUENCY CHANGE vs. VDD (25°C)
5
4
Change from Calibration (%)
3
2
1
0
-1
-2
-3
-4
-5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
DS41291F-page 292
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-40:
TYPICAL HFINTOSC FREQUENCY CHANGE OVER DEVICE VDD (85°C)
5
4
Change from Calibration (%)
3
2
1
0
-1
-2
-3
-4
-5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-41:
TYPICAL HFINTOSC FREQUENCY CHANGE vs. VDD (125°C)
5
4
Change from Calibration (%)
3
2
1
0
-1
-2
-3
-4
-5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
© 2009 Microchip Technology Inc.
DS41291F-page 293
PIC16F882/883/884/886/887
FIGURE 18-42:
TYPICAL HFINTOSC FREQUENCY CHANGE vs. VDD (-40°C)
5
4
Change from Calibration (%)
3
2
1
0
-1
-2
-3
-4
-5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VDD (V)
FIGURE 18-43:
TYPICAL VP6 REFERENCE VOLTAGE vs. VDD (25°C)
VP6 Reference Voltage vs. VDD (25×C)
0.65
0.64
0.63
VP6 (V)
0.62
0.61
0.60
0.59
Typical
0.58
0.57
0.56
0.55
2
3
4
5
5.5
VDD (V)
DS41291F-page 294
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-44:
VP6 DRIFT OVER TEMPERATURE NORMALIZED AT 25°C (VDD 5V)
4
Change from Nominal in %
3
2
1
0
-1
-2
-40
0
25
85
125
Temperature in Degrees C
FIGURE 18-45:
VP6 DRIFT OVER TEMPERATURE NORMALIZED AT 25°C (VDD 3V)
4
Change from Nominal in %
3
2
1
0
-1
-2
-40
0
25
85
125
Temperature in Degrees C
© 2009 Microchip Technology Inc.
DS41291F-page 295
PIC16F882/883/884/886/887
FIGURE 18-46:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (3V, 25°C)
Typical VP6 Reference Voltage Distribution (VDD=3V, 25×C)
35
Parts=118
Number of Parts
30
25
20
15
10
5
0.690
0.700
0.690
0.700
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
FIGURE 18-47:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (3V, 85°C)
Typical VP6 Reference Voltage Distribution (VDD=3V, 85×C)
40
35
Parts=118
Number of Parts
30
25
20
15
10
5
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
DS41291F-page 296
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-48:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (3V, 125°C)
Typical VP6 Reference Voltage Distribution (VDD=3V, 125×C)
40
35
Parts=118
Number of Parts
30
25
20
15
10
5
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
FIGURE 18-49:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (3V, -40°C)
Typical VP6 Reference Voltage Distribution (VDD=3V, -40×C)
30
Parts=118
Number of Parts
25
20
15
10
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0
0.500
5
Voltage (V)
© 2009 Microchip Technology Inc.
DS41291F-page 297
PIC16F882/883/884/886/887
FIGURE 18-50:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (5V, 25°C)
Typical VP6 Reference Voltage Distribution (VDD=5V, 25×C)
30
Number of Parts
25
Parts=118
20
15
10
5
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
FIGURE 18-51:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (5V, 85°C)
Typical VP6 Reference Voltage Distribution (VDD=5V, 85×C)
35
Number of Parts
30
Parts=118
25
20
15
10
5
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
DS41291F-page 298
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
FIGURE 18-52:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (5V, 125°C)
Typical VP6 Reference Voltage Distribution (VDD=5V, 25×C)
30
25
Number of Parts
Parts=118
20
15
10
5
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
FIGURE 18-53:
TYPICAL VP6 REFERENCE VOLTAGE DISTRIBUTION (5V, -40°C)
Typical VP6 Reference Voltage Distribution (VDD=5V, -40×C)
30
Number of Parts
25
Parts=118
20
15
10
5
0.700
0.690
0.680
0.670
0.660
0.650
0.640
0.630
0.620
0.610
0.600
0.590
0.580
0.570
0.560
0.550
0.540
0.530
0.520
0.510
0.500
0
Voltage (V)
© 2009 Microchip Technology Inc.
DS41291F-page 299
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 300
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
19.0
PACKAGING INFORMATION
19.1
Package Marking Information
28-Lead PDIP
Example
XXXXXXXXXXXXXXX
XXXXXXXXXXXXXXX
XXXXXXXXXXXXXXX
YYWWNNN
28-Lead SOIC (7.50 mm)
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXX
YYWWNNN
Example
PIC16F886/SO e3
0710017
Example
28-Lead SSOP
XXXXXXXXXXXX
XXXXXXXXXXXX
YYWWNNN
28-Lead QFN
PIC16F883
-I/SS e3
0710017
Example
XXXXXXXX
XXXXXXXX
YYWWNNN
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
PIC16F883
-I/P e3
0710017
16F886
/ML e3
0710017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
© 2009 Microchip Technology Inc.
DS41291F-page 301
PIC16F882/883/884/886/887
19.1
Package Marking Information (Continued)
40-Lead PDIP
Example
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXX
YYWWNNN
44-Lead QFN
44-Lead TQFP
PIC16F887
-I/ML e3
0710017
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
Legend: XX...X
Y
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e3
*
DS41291F-page 302
0710017
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
Note:
PIC16F885
-I/P e3
PIC16F887
-I/PT e3
0710017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
19.2
Package Details
The following sections give the technical details of the packages.
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© 2009 Microchip Technology Inc.
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DS41291F-page 307
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DS41291F-page 309
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DS41291F-page 310
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DS41291F-page 311
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DS41291F-page 312
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
APPENDIX A:
DATA SHEET
REVISION HISTORY
APPENDIX B:
Revision A (5/2006)
MIGRATING FROM
OTHER PIC®
DEVICES
Initial release of this data sheet.
This discusses some of the issues in migrating from
other PIC devices to the PIC16F88X Family of devices.
Revision B (7/2006)
B.1
Pin Diagrams (44-Pin QFN drawing); Revised Table
2-1, Addr. 1DH (CCP2CON); Section 3.0, 3.1; Section
3.4.4.6; Table 3; Table 3-1 (ANSEL); Table 3-3
(CCP2CON); Register 3-1; Register 3.2; Register 3-3;
Register 3-4; Register 3-9; Register 3-10; Register
3-11; Register 3-12; Register 3-14; Table 3-5 (ANSEL);
Figure 3-5; Figure 3-11; Figure 8-2; Figure 8-3; Figure
9-1; Register 9-1; Section 9.1.4; Example 10-4; Figure
11-5; Table 11-5 (P1M); Section 11.5.2; Section 11.5.7,
Number 4; Table 11-7 (CCP2CON); Section 12.3.1
(Para. 3); Figure 12-6 (Title); Sections 14.2, 14.3 and
14.4 DC Characteristics (Max); Table 14-4 (OSCCON);
Section 14.3 (TMR0); Section 14.3.2 (TMR0).
TABLE B-1:
Revision C
Section 19.0 Packaging Information:
package drawings and added note.
Added PIC16F882 part number.
Replaced PICmicro with PIC.
Replaced
PIC16F87X to PIC16F88X
FEATURE COMPARISON
Feature
Max Operating Speed
Max Program
Memory (Words)
PIC16F87X
PIC16F88X
20 MHz
20 MHz
8192
8192
SRAM (bytes)
368
368
A/D Resolution
10-bit
10-bit
Data EEPROM (Bytes)
256
256
Timers (8/16-bit)
2/1
2/1
Oscillator Modes
4
8
Brown-out Reset
Y
Y (2.1V/4V)
Software Control Option
of WDT/BOR
N
Y
Internal Pull-ups
RB<7:4>
RB<7:0>,
MCLR
Interrupt-on-change
RB<7:4>
RB<7:0>
Comparator
2
2
References
CVREF
CVREF and
VP6
ECCP/CCP
Revision D
Replaced Package Drawings (Rev. AM); Replaced
Development Support Section; Revised Product ID
Section.
Revision E (01/2008)
0/2
1/1
Ultra Low-Power
Wake-Up
N
Y
Extended WDT
N
Y
INTOSC Frequencies
N
32 kHz-8 MHz
Clock Switching
Added Char Data; Removed Preliminary status;
Revised Device Table (PIC16F882, I/O); Revised the
following: Pin Diagram 44 TQFP, pin 30; Table 5, I/O
RA7; Table 1-1, RA1 and RA4; Section 2.2.1; Register
2-3, INTCON; Example 3-1; Section 3.2.2; Example
3-2; Figure 6-1; Section 6.2.2; Section 6.6; Section
8.10.3; Table 9-1; Equation 11-1; Added Figure 11-14
and renumbered remaining Figures; Register 11-3;
Register 13-3; Section 14.0; Section 14.1; Section
14.9; Section 14.10; Section 17.0; Updated Package
Drawings.
Revision F (04/2009)
Revised Product ID: Removed ‘F’ (std. voltage range)
from part numbers; Revised Figure 6-1: Timer1 Block
Diagram; Revised Figure 8-3, Comparator C2 Block
Diagram; Added note to Section 8.10.3; Revised
Section 8.10.7.
© 2009 Microchip Technology Inc.
N
Y
MSSP
Standard
w/Slave
Address Mask
USART
AUSART
EUSART
8
14
ADC Channels
Note:
This device has been designed to perform
to the parameters of its data sheet. It has
been tested to an electrical specification
designed to determine its conformance
with these parameters. Due to process
differences in the manufacture of this
device, this device may have different
performance characteristics than its earlier
version. These differences may cause this
device to perform differently in your
application than the earlier version of this
device.
DS41291F-page 313
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 314
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
INDEX
A
A/D
Specifications.................................................... 263, 264
Absolute Maximum Ratings .............................................. 245
AC Characteristics
Industrial and Extended ............................................ 255
Load Conditions ........................................................ 254
ACKSTAT ......................................................................... 198
ACKSTAT Status Flag ...................................................... 198
ADC .................................................................................... 99
Acquisition Requirements ......................................... 107
Associated Registers ................................................ 109
Block Diagram............................................................. 99
Calculating Acquisition Time..................................... 107
Channel Selection..................................................... 100
Configuration............................................................. 100
Configuring Interrupt ................................................. 103
Conversion Clock...................................................... 100
Conversion Procedure .............................................. 103
Internal Sampling Switch (RSS) Impedance.............. 107
Interrupts................................................................... 101
Operation .................................................................. 102
Operation During Sleep ............................................ 102
Port Configuration ..................................................... 100
Reference Voltage (VREF)......................................... 100
Result Formatting...................................................... 102
Source Impedance.................................................... 107
Special Event Trigger................................................ 102
Starting an A/D Conversion ...................................... 102
ADCON0 Register............................................................. 104
ADCON1 Register............................................................. 105
ADRESH Register (ADFM = 0) ......................................... 106
ADRESH Register (ADFM = 1) ......................................... 106
ADRESL Register (ADFM = 0).......................................... 106
ADRESL Register (ADFM = 1).......................................... 106
Analog Input Connection Considerations............................ 90
Analog-to-Digital Converter. See ADC
ANSEL Register .................................................................. 40
ANSELH Register ............................................................... 48
Assembler
MPASM Assembler................................................... 242
B
Baud Rate Generator ........................................................ 195
BAUDCTL Register ........................................................... 162
BF ..................................................................................... 198
BF Status Flag .................................................................. 198
Block Diagrams
(CCP) Capture Mode Operation ............................... 126
ADC ............................................................................ 99
ADC Transfer Function ............................................. 108
Analog Input Model ............................................. 90, 108
Auto-Shutdown ......................................................... 141
Baud Rate Generator................................................ 195
CCP PWM................................................................. 128
Clock Source............................................................... 61
Comparator C1 ........................................................... 84
Comparator C1 and ADC Voltage Reference ............. 95
Comparator C2 ........................................................... 84
Compare ................................................................... 127
Crystal Operation ........................................................ 64
EUSART Receive ..................................................... 152
EUSART Transmit .................................................... 151
© 2009 Microchip Technology Inc.
External RC Mode ...................................................... 65
Fail-Safe Clock Monitor (FSCM)................................. 71
In-Circuit Serial Programming Connections ............. 228
Interrupt Logic........................................................... 221
MSSP (I2C Master Mode)......................................... 193
MSSP (I2C Mode)..................................................... 189
MSSP (SPI Mode) .................................................... 183
On-Chip Reset Circuit............................................... 212
PIC16F883/886 .......................................................... 14
PIC16F884/887 .......................................................... 15
PWM (Enhanced) ..................................................... 132
RA0 Pins..................................................................... 42
RA1 Pin ...................................................................... 43
RA2 Pin ...................................................................... 43
RA3 Pin ...................................................................... 44
RA4 Pin ...................................................................... 44
RA5 Pin ...................................................................... 45
RA6 Pin ...................................................................... 45
RA7 Pin ...................................................................... 46
RB0, RB1, RB2, RB3 Pins.......................................... 50
RB4, RB5, RB6, RB7 Pins.......................................... 51
RC0 Pin ...................................................................... 54
RC1 Pin ...................................................................... 54
RC2 Pin ...................................................................... 54
RC3 Pin ...................................................................... 55
RC4 Pin ...................................................................... 55
RC5 Pin ...................................................................... 55
RC6 Pin ...................................................................... 56
RC7 Pin ...................................................................... 56
RD0, RD1, RD2, RD3, RD4 Pins................................ 58
RD5, RD6, RD7 Pins .................................................. 58
RE3 Pin ...................................................................... 60
Resonator Operation .................................................. 64
Timer1 ........................................................................ 76
Timer2 ........................................................................ 81
TMR0/WDT Prescaler ................................................ 73
Watchdog Timer (WDT)............................................ 224
Break Character (12-bit) Transmit and Receive ............... 169
BRG .................................................................................. 195
Brown-out Reset (BOR).................................................... 214
Associated ................................................................ 215
Specifications ........................................................... 259
Timing and Characteristics ....................................... 258
Bus Collision During a Repeated Start Condition ............. 206
Bus Collision During a Start Condition.............................. 204
Bus Collision During a Stop Condition.............................. 207
C
C Compilers
MPLAB C18.............................................................. 242
MPLAB C30.............................................................. 242
Capture Module. See Enhanced Capture/Compare/
PWM(ECCP)
Capture/Compare/PWM (CCP)
Associated Registers w/ Capture, Compare
and Timer1 ....................................................... 149
Associated Registers w/ PWM and Timer2 .............. 149
Capture Mode........................................................... 126
CCP Pin Configuration ............................................. 126
Compare Mode......................................................... 127
CCP Pin Configuration ..................................... 127
Software Interrupt Mode ........................... 126, 127
Special Event Trigger ....................................... 127
Timer1 Mode Selection............................. 126, 127
DS41291F-page 315
PIC16F882/883/884/886/887
Prescaler ................................................................... 126
PWM Mode ............................................................... 128
Duty Cycle......................................................... 129
Effects of Reset................................................. 131
Example PWM Frequencies and
Resolutions, 20 MHZ ................................ 130
Example PWM Frequencies and
Resolutions, 8 MHz................................... 130
Operation in Sleep Mode .................................. 131
Setup for Operation........................................... 131
System Clock Frequency Changes................... 131
PWM Period .............................................................. 129
Setup for PWM Operation ......................................... 131
Timer Resources....................................................... 125
CCP1CON (Enhanced) Register....................................... 124
CCP2CON Register .......................................................... 125
Clock Accuracy with Asynchronous Operation ................. 160
Clock Sources
External Modes ........................................................... 63
EC ....................................................................... 63
HS ....................................................................... 64
LP........................................................................ 64
OST..................................................................... 63
RC....................................................................... 65
XT ....................................................................... 64
Internal Modes ............................................................ 65
Frequency Selection ........................................... 67
HFINTOSC.......................................................... 65
HFINTOSC/LFINTOSC Switch Timing ............... 67
INTOSC .............................................................. 65
INTOSCIO........................................................... 65
LFINTOSC .......................................................... 67
Clock Switching................................................................... 69
CM1CON0 Register ............................................................ 88
CM2CON0 Register ............................................................ 89
CM2CON1 Register ............................................................ 91
Code Examples
A/D Conversion ......................................................... 103
Assigning Prescaler to Timer0 .................................... 74
Assigning Prescaler to WDT ....................................... 74
Changing Between Capture Prescalers .................... 126
Indirect Addressing ..................................................... 37
Initializing PORTA ....................................................... 39
Initializing PORTB ....................................................... 47
Initializing PORTC....................................................... 53
Initializing PORTD....................................................... 57
Initializing PORTE ....................................................... 59
Loading the SSPBUF Register ................................. 184
Saving STATUS and W Registers in RAM ............... 223
Ultra Low-Power Wake-up Initialization ...................... 41
Write Verify ............................................................... 120
Writing to Flash Program Memory ............................ 119
Code Protection ................................................................ 227
Comparator
C2OUT as T1 Gate ............................................... 77, 91
Effects of a Reset........................................................ 87
Operation .................................................................... 83
Operation During Sleep .............................................. 87
Response Time ........................................................... 85
Specifications ............................................................ 262
Synchronizing COUT w/Timer1 .................................. 91
Comparator Module ............................................................ 83
Associated Registers .................................................. 97
C1 Output State Versus Input Conditions ................... 85
Comparator Voltage Reference (CVREF)
DS41291F-page 316
Response Time........................................................... 85
Comparator Voltage Reference (CVREF) ............................ 94
Effects of a Reset ....................................................... 87
Specifications ........................................................... 262
Compare Module. See Enhanced Capture/
Compare/PWM (ECCP)
CONFIG1 Register ........................................................... 210
CONFIG2 Register ........................................................... 211
Configuration Bits ............................................................. 210
CPU Features ................................................................... 209
Customer Change Notification Service............................. 323
Customer Notification Service .......................................... 323
Customer Support............................................................. 323
D
Data EEPROM Memory.................................................... 111
Associated Registers ................................................ 121
Code Protection ........................................................ 120
Reading .................................................................... 114
Writing ...................................................................... 114
Data Memory ...................................................................... 22
DC Characteristics
Extended .................................................................. 250
Industrial ................................................................... 249
Industrial and Extended ............................ 247, 248, 251
Development Support ....................................................... 241
Device Overview................................................................. 13
E
ECCP. See Enhanced Capture/Compare/PWM
ECCPAS Register............................................................. 142
EEADR Register ............................................................... 112
EEADR Registers ............................................................. 111
EEADRH Registers........................................................... 111
EECON1 Register..................................................... 111, 113
EECON2 Register............................................................. 111
EEDAT Register ............................................................... 112
EEDATH Register............................................................. 112
EEPROM Data Memory
Avoiding Spurious Write ........................................... 120
Write Verify ............................................................... 120
Effects of Reset
PWM mode ............................................................... 131
Electrical Specifications .................................................... 245
Enhanced Capture/Compare/PWM .................................. 123
Enhanced Capture/Compare/PWM (ECCP)
Enhanced PWM Mode.............................................. 132
Auto-Restart ..................................................... 143
Auto-shutdown.................................................. 141
Direction Change in Full-Bridge Output Mode.. 138
Full-Bridge Application...................................... 136
Full-Bridge Mode .............................................. 136
Half-Bridge Application ..................................... 135
Half-Bridge Application Examples .................... 144
Half-Bridge Mode.............................................. 135
Output Relationships (Active-High and
Active-Low).............................................. 133
Output Relationships Diagram.......................... 134
Programmable Dead Band Delay..................... 144
Shoot-through Current ...................................... 144
Start-up Considerations .................................... 140
Specifications ........................................................... 261
Timer Resources ...................................................... 124
Enhanced Universal Synchronous
Asynchronous Receiver Transmitter (EUSART)....... 151
Errata .................................................................................. 12
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
EUSART ........................................................................... 151
Associated Registers
Baud Rate Generator........................................ 163
Asynchronous Mode ................................................. 153
12-bit Break Transmit and Receive .................. 169
Associated Registers
Receive..................................................... 159
Transmit.................................................... 155
Auto-Wake-up on Break ................................... 168
Baud Rate Generator (BRG) ............................ 163
Clock Accuracy ................................................. 160
Receiver............................................................ 156
Setting up 9-bit Mode with Address Detect....... 158
Transmitter........................................................ 153
Baud Rate Generator (BRG)
Auto Baud Rate Detect ..................................... 167
Baud Rate Error, Calculating ............................ 163
Baud Rates, Asynchronous Modes .................. 164
Formulas ........................................................... 163
High Baud Rate Select (BRGH Bit) .................. 163
Synchronous Master Mode ............................... 171, 175
Associated Registers
Receive..................................................... 174
Transmit.................................................... 172
Reception.......................................................... 173
Requirements, Synchronous Receive .............. 266
Requirements, Synchronous Transmission ...... 266
Timing Diagram, Synchronous Receive ........... 266
Timing Diagram, Synchronous Transmission ... 266
Transmission .................................................... 171
Synchronous Slave Mode
Associated Registers
Receive..................................................... 176
Transmit.................................................... 175
Reception.......................................................... 176
Transmission .................................................... 175
F
Fail-Safe Clock Monitor....................................................... 71
Fail-Safe Condition Clearing ....................................... 71
Fail-Safe Detection ..................................................... 71
Fail-Safe Operation..................................................... 71
Reset or Wake-up from Sleep..................................... 71
Firmware Instructions........................................................ 231
Flash Program Memory .................................................... 111
Writing....................................................................... 117
Fuses. See Configuration Bits
G
General Call Address Support .......................................... 192
General Purpose Register File............................................ 22
I
I2C (MSSP Module)
ACK Pulse......................................................... 189, 190
Addressing ................................................................ 190
Read/Write Bit Information (R/W Bit) ........................ 190
Reception.................................................................. 190
Serial Clock (RC3/SCK/SCL).................................... 190
Slave Mode ............................................................... 189
Transmission............................................................. 190
I2C Master Mode Reception.............................................. 198
I2C Master Mode Repeated Start Condition Timing.......... 197
I2C Module
Acknowledge Sequence Timing................................ 201
Baud Rate Generator................................................ 195
© 2009 Microchip Technology Inc.
BRG Block Diagram ................................................. 195
BRG Reset Due to SDA Arbitration During
Start Condition.................................................. 205
BRG Timing .............................................................. 195
Bus Collision
Acknowledge .................................................... 203
Repeated Start Condition ................................. 206
Repeated Start Condition Timing (Case1)........ 206
Repeated Start Condition Timing (Case2)........ 206
Start Condition.................................................. 204
Start Condition Timing .............................. 204, 205
Stop Condition .................................................. 207
Stop Condition Timing (Case 1) ....................... 207
Stop Condition Timing (Case 2) ....................... 207
Bus Collision timing .................................................. 203
Clock Arbitration ....................................................... 202
Clock Arbitration Timing (Master Transmit) .............. 202
Effect of a Reset ....................................................... 202
General Call Address Support .................................. 192
Master Mode............................................................. 193
Master Mode 7-bit Reception Timing........................ 200
Master Mode Operation............................................ 194
Master Mode Start Condition Timing ........................ 196
Master Mode Support ............................................... 193
Master Mode Transmission ...................................... 198
Master Mode Transmit Sequence ............................ 194
Multi-Master Mode.................................................... 203
Repeat Start Condition Timing Waveform ................ 197
Sleep Operation........................................................ 202
Stop Condition Receive or Transmit Timing ............. 202
Stop Condition Timing .............................................. 201
Waveforms for 7-bit Reception ................................. 191
Waveforms for 7-bit Transmission............................ 191
ID Locations...................................................................... 227
In-Circuit Debugger........................................................... 229
In-Circuit Serial Programming (ICSP)............................... 227
Indirect Addressing, INDF and FSR registers..................... 37
Instruction Format............................................................. 231
Instruction Set................................................................... 231
ADDLW..................................................................... 233
ADDWF .................................................................... 233
ANDLW..................................................................... 233
ANDWF .................................................................... 233
BCF .......................................................................... 233
BSF........................................................................... 233
BTFSC...................................................................... 233
BTFSS ...................................................................... 234
CALL......................................................................... 234
CLRF ........................................................................ 234
CLRW ....................................................................... 234
CLRWDT .................................................................. 234
COMF ....................................................................... 234
DECF........................................................................ 234
DECFSZ ................................................................... 235
GOTO ....................................................................... 235
INCF ......................................................................... 235
INCFSZ..................................................................... 235
IORLW ...................................................................... 235
IORWF...................................................................... 235
MOVF ....................................................................... 236
MOVLW .................................................................... 236
MOVWF.................................................................... 236
NOP.......................................................................... 236
RETFIE..................................................................... 237
RETLW ..................................................................... 237
DS41291F-page 317
PIC16F882/883/884/886/887
RETURN ................................................................... 237
RLF ........................................................................... 238
RRF........................................................................... 238
SLEEP ...................................................................... 238
SUBLW ..................................................................... 238
SUBWF ..................................................................... 239
SWAPF ..................................................................... 239
XORLW ..................................................................... 239
XORWF..................................................................... 239
Summary Table......................................................... 232
INTCON Register ................................................................ 31
Inter-Integrated Circuit. See I2C
Internal Oscillator Block .................................................... 256
INTOSC
Specifications.................................................... 257
Internal Sampling Switch (RSS) Impedance ...................... 107
Internet Address................................................................ 323
Interrupts ........................................................................... 220
ADC .......................................................................... 103
Associated Registers ................................................ 222
Context Saving.......................................................... 223
Interrupt-on-Change.................................................... 47
PORTB Interrupt-on-Change .................................... 221
RB0/INT .................................................................... 220
Timer0 ....................................................................... 221
TMR1 .......................................................................... 78
INTOSC
Specifications ............................................................ 256
INTOSC Specifications ............................................. 256, 257
IOCB Register ..................................................................... 49
L
Load Conditions ................................................................ 254
M
Master Mode ..................................................................... 193
Master Mode Support........................................................ 193
Master Synchronous Serial Port. See MSSP
MCLR ................................................................................ 213
Internal ...................................................................... 213
Memory Organization.......................................................... 21
Data ............................................................................ 22
Program ...................................................................... 21
Microchip Internet Web Site .............................................. 323
Migrating from other PICmicro Devices ............................ 313
MPLAB ASM30 Assembler, Linker, Librarian ................... 242
MPLAB ICD 2 In-Circuit Debugger.................................... 243
MPLAB ICE 2000 High-Performance Universal
In-Circuit Emulator .................................................... 243
MPLAB Integrated Development Environment Software .. 241
MPLAB PM3 Device Programmer..................................... 243
MPLAB REAL ICE In-Circuit Emulator System................. 243
MPLINK Object Linker/MPLIB Object Librarian ................ 242
MSSP ................................................................................ 179
Block Diagram (SPI Mode) ....................................... 183
I2C Mode. See I2C
SPI Mode .................................................................. 183
SPI Mode. See SPI
MSSP Module
Control Registers ...................................................... 179
I2C Operation ............................................................ 189
SPI Master Mode ...................................................... 185
SPI Slave Mode ........................................................ 186
Multi-Master Communication, Bus Collision and
Bus Arbitration .......................................................... 203
Multi-Master Mode ............................................................ 203
DS41291F-page 318
O
OPCODE Field Descriptions............................................. 231
OPTION Register................................................................ 30
OPTION_REG Register...................................................... 75
OSCCON Register.............................................................. 62
Oscillator
Associated Registers ............................................ 72, 80
Oscillator Module ................................................................ 61
EC............................................................................... 61
HFINTOSC ................................................................. 61
HS............................................................................... 61
INTOSC ...................................................................... 61
INTOSCIO .................................................................. 61
LFINTOSC .................................................................. 61
LP ............................................................................... 61
RC .............................................................................. 61
RCIO........................................................................... 61
XT ............................................................................... 61
Oscillator Parameters ....................................................... 256
Oscillator Specifications.................................................... 255
Oscillator Start-up Timer (OST)
Specifications ........................................................... 259
Oscillator Switching
Fail-Safe Clock Monitor .............................................. 71
Two-Speed Clock Start-up.......................................... 69
OSCTUNE Register............................................................ 66
P
P1A/P1B/P1C/P1D.See Enhanced Capture/
Compare/PWM (ECCP)............................................ 132
Packaging ......................................................................... 301
Marking ............................................................. 301, 302
PDIP Details ............................................................. 303
PCL and PCLATH............................................................... 37
Stack........................................................................... 37
PCON Register ........................................................... 36, 215
PICSTART Plus Development Programmer..................... 244
PIE1 Register...................................................................... 32
PIE2 Register...................................................................... 33
Pin Diagram
PIC16F883/886, 28-pin (PDIP, SOIC, SSOP) .............. 3
PIC16F883/886, 28-pin (QFN)...................................... 4
PIC16F884/887, 40-Pin (PDIP) .................................... 6
PIC16F884/887, 44-pin (QFN)...................................... 8
PIC16F884/887, 44-pin (TQFP).................................. 10
Pinout Descriptions
PIC16F883/886 .......................................................... 16
PIC16F884/887 .......................................................... 18
PIR1 Register ..................................................................... 34
PIR2 Register ..................................................................... 35
PORTA ............................................................................... 39
Additional Pin Functions ............................................. 40
ANSEL Register ................................................. 40
Ultra Low-Power Wake-up............................ 40, 41
Associated Registers .................................................. 46
Pin Descriptions and Diagrams .................................. 42
RA0............................................................................. 42
RA1............................................................................. 43
RA2............................................................................. 43
RA3............................................................................. 44
RA4............................................................................. 44
RA5............................................................................. 45
RA6............................................................................. 45
RA7............................................................................. 46
Specifications ........................................................... 257
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
PORTA Register ................................................................. 39
PORTB................................................................................ 47
Additional Pin Functions ............................................. 47
ANSELH Register ............................................... 47
Weak Pull-up ...................................................... 47
Associated Registers .................................................. 52
Interrupt-on-Change.................................................... 47
P1B/P1C/P1D.See Enhanced Capture/
Compare/PWM+ (ECCP+).................................. 47
Pin Descriptions and Diagrams................................... 50
RB0 ............................................................................. 50
RB1 ............................................................................. 50
RB2 ............................................................................. 50
RB3 ............................................................................. 50
RB4 ............................................................................. 51
RB5 ............................................................................. 51
RB6 ............................................................................. 51
RB7 ............................................................................. 51
PORTB Register ................................................................. 48
PORTC ............................................................................... 53
Associated Registers .................................................. 56
P1A.See Enhanced Capture/Compare/
PWM+ (ECCP+) ................................................. 53
RC0............................................................................. 54
RC1............................................................................. 54
RC2............................................................................. 54
RC3............................................................................. 55
RC3 Pin..................................................................... 190
RC4............................................................................. 55
RC5............................................................................. 55
RC6............................................................................. 56
RC7............................................................................. 56
Specifications............................................................ 257
PORTC Register ................................................................. 53
PORTD ............................................................................... 57
Associated Registers .................................................. 58
P1B/P1C/P1D.See Enhanced Capture/
Compare/PWM+ (ECCP+).................................. 57
RD0, RD1, RD2, RD3, RD4 ........................................ 58
RD5............................................................................. 58
RD6............................................................................. 58
RD7............................................................................. 58
PORTD Register ................................................................. 57
PORTE................................................................................ 59
Associated Registers .................................................. 60
RE0 ............................................................................. 60
RE1 ............................................................................. 60
RE2 ............................................................................. 60
RE3 ............................................................................. 60
PORTE Register ................................................................. 59
Power-Down Mode (Sleep) ............................................... 226
Power-on Reset (POR) ..................................................... 213
Power-up Timer (PWRT) .................................................. 213
Specifications............................................................ 259
Precision Internal Oscillator Parameters........................... 257
Prescaler
Shared WDT/Timer0 ................................................... 74
Switching Prescaler Assignment................................. 74
Program Memory ................................................................ 21
Map and Stack ............................................................ 21
Map and Stack (PIC16F883/884) ............................... 21
Map and Stack (PIC16F886/887) ............................... 21
Programming, Device Instructions .................................... 231
PSTRCON Register .......................................................... 146
Pulse Steering................................................................... 146
© 2009 Microchip Technology Inc.
PWM (ECCP Module)
Pulse Steering .......................................................... 146
Steering Synchronization.......................................... 148
PWM Mode. See Enhanced Capture/Compare/PWM ...... 132
PWM1CON Register......................................................... 145
R
RCREG............................................................................. 158
RCSTA Register ............................................................... 161
Reader Response............................................................. 324
Read-Modify-Write Operations ......................................... 231
Register
RCREG Register ...................................................... 167
Registers
ADCON0 (ADC Control 0) ........................................ 104
ADCON1 (ADC Control 1) ........................................ 105
ADRESH (ADC Result High) with ADFM = 0) .......... 106
ADRESH (ADC Result High) with ADFM = 1) .......... 106
ADRESL (ADC Result Low) with ADFM = 0)............ 106
ADRESL (ADC Result Low) with ADFM = 1)............ 106
ANSEL (Analog Select) .............................................. 40
ANSELH (Analog Select High) ................................... 48
BAUDCTL (Baud Rate Control)................................ 162
CCP1CON (Enhanced CCP1 Control) ..................... 124
CCP2CON (CCP2 Control) ...................................... 125
CM1CON0 (C1 Control) ............................................. 88
CM2CON0 (C2 Control) ............................................. 89
CM2CON1 (C2 Control) ............................................. 91
CONFIG1 (Configuration Word Register 1).............. 210
CONFIG2 (Configuration Word Register 2).............. 211
ECCPAS (Enhanced CCP Auto-shutdown Control) . 142
EEADR (EEPROM Address) .................................... 112
EECON1 (EEPROM Control 1) ................................ 113
EEDAT (EEPROM Data) .......................................... 112
EEDATH (EEPROM Data) ....................................... 112
INTCON (Interrupt Control) ........................................ 31
IOCB (Interrupt-on-Change PORTB).......................... 49
OPTION_REG (OPTION)..................................... 30, 75
OSCCON (Oscillator Control)..................................... 62
OSCTUNE (Oscillator Tuning).................................... 66
PCON (Power Control Register)................................. 36
PCON (Power Control) ............................................. 215
PIE1 (Peripheral Interrupt Enable 1) .......................... 32
PIE2 (Peripheral Interrupt Enable 2) .......................... 33
PIR1 (Peripheral Interrupt Register 1) ........................ 34
PIR2 (Peripheral Interrupt Request 2) ........................ 35
PORTA ....................................................................... 39
PORTB ....................................................................... 48
PORTC ....................................................................... 53
PORTD ....................................................................... 57
PORTE ....................................................................... 59
PSTRCON (Pulse Steering Control)......................... 146
PWM1CON (Enhanced PWM Control) ..................... 145
RCSTA (Receive Status and Control) ...................... 161
Reset Values ............................................................ 217
Reset Values (special registers)............................... 219
Special Function Register Map
PIC16F883/884 ............................................ 23, 24
PIC16F886/887 .................................................. 25
Special Function Registers......................................... 22
Special Register Summary
Bank 0 ................................................................ 26
Bank 1 ................................................................ 27
Bank 2 ................................................................ 28
Bank 3 ................................................................ 28
SRCON (SR Latch Control)........................................ 93
DS41291F-page 319
PIC16F882/883/884/886/887
SSPCON (MSSP Control 1)...................................... 181
SSPCON2 (SSP Control 2)....................................... 182
SSPMSK (SSP Mask) ............................................... 208
SSPSTAT (SSP Status) ............................................ 180
STATUS ...................................................................... 29
T1CON ........................................................................ 79
T2CON ........................................................................ 82
TRISA (Tri-State PORTA) ........................................... 39
TRISB (Tri-State PORTB) ........................................... 48
TRISC (Tri-State PORTC) .......................................... 53
TRISD (Tri-State PORTD) .......................................... 57
TRISE (Tri-State PORTE) ........................................... 59
TXSTA (Transmit Status and Control) ...................... 160
VRCON (Voltage Reference Control) ......................... 97
WDTCON (Watchdog Timer Control)........................ 225
WPUB (Weak Pull-up PORTB) ................................... 49
Reset................................................................................. 212
Revision History ................................................................ 313
S
SCK................................................................................... 183
SDI .................................................................................... 183
SDO .................................................................................. 183
Serial Clock, SCK.............................................................. 183
Serial Data In, SDI ............................................................ 183
Serial Data Out, SDO........................................................ 183
Serial Peripheral Interface. See SPI
Shoot-through Current ...................................................... 144
Slave Mode General Call Address Sequence................... 192
Slave Select Synchronization............................................ 186
Slave Select, SS ............................................................... 183
Sleep ................................................................................. 226
Wake-up.................................................................... 226
Wake-up Using Interrupts ......................................... 226
Software Simulator (MPLAB SIM)..................................... 242
SPBRG.............................................................................. 163
SPBRGH ........................................................................... 163
Special Event Trigger........................................................ 102
Special Function Registers ................................................. 22
SPI
Master Mode ............................................................. 185
Serial Clock ............................................................... 183
Serial Data In ............................................................ 183
Serial Data Out ......................................................... 183
Slave Select .............................................................. 183
SPI clock ................................................................... 185
SPI Mode .................................................................. 183
SPI Bus Modes ................................................................. 188
SPI Mode
Associated Registers with SPI Operation ................. 188
Bus Mode Compatibility ............................................ 188
Effects of a Reset...................................................... 188
Enabling SPI I/O ....................................................... 184
Operation .................................................................. 183
Sleep Operation ........................................................ 188
SPI Module
Slave Mode ............................................................... 186
Slave Select Synchronization ................................... 186
Slave Synchronization Timing................................... 186
Slave Timing with CKE = 0 ....................................... 187
Slave Timing with CKE = 1 ....................................... 187
SRCON Register................................................................. 93
SS ..................................................................................... 183
SSP
SSPBUF.................................................................... 185
SSPSR ...................................................................... 185
DS41291F-page 320
SSPCON Register ............................................................ 181
SSPCON2 Register .......................................................... 182
SSPMSK Register ............................................................ 208
SSPOV ............................................................................. 198
SSPOV Status Flag .......................................................... 198
SSPSTAT Register ........................................................... 180
R/W Bit ..................................................................... 190
STATUS Register ............................................................... 29
T
T1CON Register ................................................................. 79
T2CON Register ................................................................. 82
Thermal Considerations.................................................... 253
Time-out Sequence .......................................................... 215
Timer0................................................................................. 73
Associated Registers .................................................. 75
External Clock............................................................. 74
Interrupt ...................................................................... 75
Operation .............................................................. 73, 76
Specifications ........................................................... 260
T0CKI ......................................................................... 74
Timer1................................................................................. 76
Associated Registers .................................................. 80
Asynchronous Counter Mode ..................................... 77
Reading and Writing ........................................... 77
Interrupt ...................................................................... 78
Modes of Operation .................................................... 76
Operation During Sleep .............................................. 78
Oscillator..................................................................... 77
Prescaler .................................................................... 77
Specifications ........................................................... 260
Timer1 Gate
Inverting Gate ..................................................... 77
Selecting Source .......................................... 77, 91
SR Latch............................................................. 92
Synchronizing COUT w/Timer1 .......................... 91
TMR1H Register ......................................................... 76
TMR1L Register.......................................................... 76
Timer2
Associated Registers .................................................. 82
Timers
Timer1
T1CON ............................................................... 79
Timer2
T2CON ............................................................... 82
Timing Diagrams
A/D Conversion......................................................... 265
A/D Conversion (Sleep Mode) .................................. 265
Acknowledge Sequence Timing ............................... 201
Asynchronous Reception.......................................... 158
Asynchronous Transmission..................................... 154
Asynchronous Transmission (Back to Back) ............ 154
Auto Wake-up Bit (WUE) During Normal Operation . 168
Auto Wake-up Bit (WUE) During Sleep .................... 169
Automatic Baud Rate Calibration.............................. 167
Baud Rate Generator with Clock Arbitration............. 195
BRG Reset Due to SDA Arbitration .......................... 205
Brown-out Reset (BOR)............................................ 258
Brown-out Reset Situations ...................................... 214
Bus Collision
Start Condition Timing ...................................... 204
Bus Collision During a Repeated Start
Condition (Case 1)............................................ 206
Bus Collision During a Repeated Start
Condition (Case2)............................................. 206
Bus Collision During a Start Condition (SCL = 0) ..... 205
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
Bus Collision During a Stop Condition ...................... 207
Bus Collision for Transmit and Acknowledge............ 203
CLKOUT and I/O....................................................... 257
Clock Timing ............................................................. 255
Comparator Output ..................................................... 83
Enhanced Capture/Compare/PWM (ECCP) ............. 261
EUSART Synchronous Receive (Master/Slave) ....... 266
EUSART Synchronous Transmission
(Master/Slave) .................................................. 266
Fail-Safe Clock Monitor (FSCM) ................................. 72
Full-Bridge PWM Output ........................................... 137
Half-Bridge PWM Output .................................. 135, 144
I2C Bus Data ............................................................. 270
I2C Bus Start/Stop Bits.............................................. 269
I2C Master Mode First Start Bit Timing ..................... 196
I2C Master Mode Reception Timing.......................... 200
I2C Master Mode Transmission Timing..................... 199
I2C Module
Bus Collision
Transmit Timing ........................................ 203
INT Pin Interrupt........................................................ 222
Internal Oscillator Switch Timing................................. 68
Master Mode Transmit Clock Arbitration................... 202
PWM Auto-shutdown
Auto-restart Enabled ......................................... 143
Firmware Restart .............................................. 143
PWM Direction Change ............................................ 138
PWM Direction Change at Near 100% Duty Cycle ... 139
PWM Output (Active-High)........................................ 133
PWM Output (Active-Low) ........................................ 134
Repeat Start Condition.............................................. 197
Reset, WDT, OST and Power-up Timer ................... 258
Send Break Character Sequence ............................. 170
Slave Synchronization .............................................. 186
SPI Master Mode (CKE = 1, SMP = 1) ..................... 267
SPI Mode Timing (Master Mode) SPI Mode
Master Mode Timing Diagram .......................... 185
SPI Mode Timing (Slave Mode with CKE = 0) .......... 187
SPI Mode Timing (Slave Mode with CKE = 1) .......... 187
SPI Slave Mode (CKE = 0) ....................................... 268
SPI Slave Mode (CKE = 1) ....................................... 268
Stop Condition Receive or Transmit ......................... 202
Synchronous Reception (Master Mode, SREN) ....... 174
Synchronous Transmission....................................... 172
Synchronous Transmission (Through TXEN) ........... 172
Time-out Sequence
Case 1 .............................................................. 216
Case 2 .............................................................. 216
Case 3 .............................................................. 216
Timer0 and Timer1 External Clock ........................... 260
Timer1 Incrementing Edge.......................................... 78
Two Speed Start-up .................................................... 70
Wake-up from Interrupt ............................................. 227
Timing Parameter Symbology........................................... 254
Timing Requirements
I2C Bus Data ............................................................. 271
I2C Bus Start/Stop Bits ............................................. 270
SPI Mode .................................................................. 269
TRISA ................................................................................. 39
TRISA Register ................................................................... 39
TRISB ................................................................................. 47
TRISB Register ................................................................... 48
TRISC ................................................................................. 53
TRISC Register ................................................................... 53
TRISD ................................................................................. 57
© 2009 Microchip Technology Inc.
TRISD Register................................................................... 57
TRISE ................................................................................. 59
TRISE Register................................................................... 59
Two-Speed Clock Start-up Mode........................................ 69
TXREG ............................................................................. 153
TXSTA Register................................................................ 160
BRGH Bit .................................................................. 163
U
Ultra Low-Power Wake-up................................ 16, 18, 40, 41
V
Voltage Reference (VR)
Specifications ........................................................... 262
Voltage Reference. See Comparator
Voltage Reference (CVREF)
Voltage References
Associated Registers.................................................. 97
VP6 Stabilization ........................................................ 94
VREF. SEE ADC Reference Voltage
W
Wake-up on Break ............................................................ 168
Wake-up Using Interrupts ................................................. 226
Watchdog Timer (WDT).................................................... 224
Associated Registers................................................ 225
Clock Source ............................................................ 224
Modes....................................................................... 224
Period ....................................................................... 224
Specifications ........................................................... 259
Waveform for Slave Mode General Call
Address Sequence ................................................... 192
WCOL ............................................................... 196, 198, 201
WCOL Status Flag............................................ 196, 198, 201
WDTCON Register ........................................................... 225
WPUB Register................................................................... 49
WWW Address ................................................................. 323
WWW, On-Line Support ..................................................... 12
DS41291F-page 321
PIC16F882/883/884/886/887
NOTES:
DS41291F-page 322
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
THE MICROCHIP WEB SITE
CUSTOMER SUPPORT
Microchip provides online support via our WWW site at
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•
•
•
•
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CUSTOMER CHANGE NOTIFICATION
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To register, access the Microchip web site at
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© 2009 Microchip Technology Inc.
DS41291F-page 323
PIC16F882/883/884/886/887
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150.
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Device: PIC16F882/883/884/886/887
Literature Number: DS41291F
Questions:
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2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this document easy to follow? If not, why?
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DS41291F-page 324
© 2009 Microchip Technology Inc.
PIC16F882/883/884/886/887
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
X
/XX
XXX
Device
Temperature
Range
Package
Pattern
Examples:
a)
b)
Device:
PIC16F883(1), PIC16F883T(1, 2), PIC16F884(1),
PIC16F884T(1, 2), PIC16F886(1), PIC16F886T(1, 2),
PIC16F887(1), PIC16F887T(1, 2)
VDD range 2.0V to 5.5V
Temperature
Range:
I
E
Package:
ML
P
PT
SO
SP
SS
Pattern:
= -40°C to +85°C
= -40°C to +125°C
=
=
=
=
=
=
PIC16F883-E/P 301 = Extended Temp., PDIP
package, 20 MHz, QTP pattern #301
PIC16F883-I/SO = Industrial Temp., SOIC
package, 20 MHz
(Industrial)
(Extended)
Quad Flat No Leads (QFN)
Plastic DIP
Plastic Thin-Quad Flatpack (TQFP)
Plastic Small Outline (SOIC) (7.50 mm)
Skinny Plastic DIP
Plastic Shrink Small Outline
Note
1:
T = In tape and reel SSOP, SOIC and
QFN packages only.
QTP, SQTP, Code or Special Requirements
(blank otherwise)
© 2009 Microchip Technology Inc.
DS41291F-page 325
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
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Fax: 480-792-7277
Technical Support:
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Web Address:
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Fax: 91-80-3090-4080
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
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Tel: 905-673-0699
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Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
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Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Hsin Chu
Tel: 886-3-6578-300
Fax: 886-3-6578-370
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Zhuhai
Tel: 86-756-3210040
Fax: 86-756-3210049
03/26/09
DS41291F-page 326
© 2009 Microchip Technology Inc.