PIC16F87_05 Datasheet, PDF (60/228 Pages) Microchip Technology – 18/20/28-Pin Enhanced Flash Microcontrollers with nanoWatt Technology

PIC16F87/88
TABLE 5-3: PORTB FUNCTIONS
Name
Bit# Buffer
Function
RB0/INT/CCP1⁽⁷⁾
RB1/SDI/SDA
RB2/SDO/RX/DT
RB3/PGM/CCP1^(3,7)
RB4/SCK/SCL
bit 0 TTL/ST⁽¹⁾ Input/output pin or external interrupt input.
Capture input/Compare output/PWM output pin.
Internal software programmable weak pull-up.
bit 1 TTL/ST⁽⁵⁾ Input/output pin, SPI™ data input pin or I²C™ data I/O pin.
Internal software programmable weak pull-up.
bit 2 TTL/ST⁽⁴⁾ Input/output pin, SPI data output pin.
AUSART asynchronous receive or synchronous data.
Internal software programmable weak pull-up.
bit 3 TTL/ST⁽²⁾ Input/output pin, programming in LVP mode or Capture input/Compare
output/PWM output pin. Internal software programmable weak pull-up.
bit 4 TTL/ST⁽⁵⁾ Input/output pin or SPI and I²C clock pin (with interrupt-on-change).
Internal software programmable weak pull-up.
RB5/SS/TX/CK
RB6/AN5⁽⁶⁾/PGC/
T1OSO/T1CKI
RB7/AN6⁽⁶⁾/PGD/
T1OSI
bit 5
TTL Input/output pin or SPI slave select pin (with interrupt-on-change).
AUSART asynchronous transmit or synchronous clock.
Internal software programmable weak pull-up.
bit 6 TTL/ST⁽²⁾ Input/output pin, analog input⁽⁶⁾, serial programming clock
(with interrupt-on-change), Timer1 oscillator output pin or Timer1 clock
input pin. Internal software programmable weak pull-up.
bit 7 TTL/ST⁽²⁾ Input/output pin, analog input⁽⁶⁾, serial programming data (with
interrupt-on-change) or Timer1 oscillator input pin.
Internal software programmable weak pull-up.
Legend: TTL = TTL input, ST = Schmitt Trigger input
Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt.
2: This buffer is a Schmitt Trigger input when used in Serial Programming mode.
3: Low-Voltage ICSP™ Programming (LVP) is enabled by default, which disables the RB3 I/O function. LVP
must be disabled to enable RB3 as an I/O pin and allow maximum compatibility to the other 18-pin
mid-range devices.
4: This buffer is a Schmitt Trigger input when configured for CCP or SSP mode.
5: This buffer is a Schmitt Trigger input when configured for SPI or I²C mode.
6: PIC16F88 only.
7: The CCP1 pin is determined by the CCPMX bit in Configuration Word 1 register.
TABLE 5-4: SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Address
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
06h, 106h PORTB
RB7
RB6
RB5
RB4
RB3
RB2 RB1
RB0 xxxx xxxx⁽¹⁾ uuuu uuuu⁽¹⁾
00xx xxxx⁽²⁾ 00uu uuuu⁽²⁾
86h, 186h TRISB
PORTB Data Direction Register
1111 1111 1111 1111
81h, 181h OPTION_REG RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 1111 1111
9Bh
ANSEL⁽²⁾
—
ANS6 ANS5 ANS4 ANS3 ANS2 ANS1 ANS0 -111 1111
1111 1111
-111 1111
Legend:
Note 1:
2:
x = unknown, u = unchanged, - = unimplemented, read as ‘0’. Shaded cells are not used by PORTB.
This value applies only to the PIC16F87.
This value applies only to the PIC16F88.
DS30487C-page 58
 2005 Microchip Technology Inc.