PIC16F87-E Datasheet, PDF (61/228 Pages) Microchip Technology – 18/20/28-Pin Enhan lashMicrocontrollers with nanoWatt Technology

FIGURE 5-8:
PIC16F87/88
BLOCK DIAGRAM OF RB0/INT/CCP1⁽³⁾ PIN
CCP1M<3:0> = 1000, 1001, 11xx and CCPMX = 1
CCP
0
1
CCP1M<3:0> = 000
RBPU⁽²⁾
Data Bus
WR PORTB
WR TRISB
Data Latch
DQ
CK
TRIS Latch
DQ
CK
VDD
P
Weak
Pull-up
I/O pin⁽¹⁾
TTL
Input
Buffer
RD TRISB
RD PORTB
QD
EN
To INT0 or CCP
RD PORTB
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s) and clear the RBPU bit.
3: The CCP1 pin is determined by the CCPMX bit in Configuration Word 1 register.
 2005 Microchip Technology Inc.
DS30487C-page 59