Datasheet

 2001-2013 Microchip Technology Inc. DS39598F-page 45
PIC16F818/819
FIGURE 5-8: BLOCK DIAGRAM OF RB0 PIN
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.
Data Latch
RBPU
(2)
P
V
DD
QD
CK
QD
CK
Q
D
EN
Data Bus
WR
WR
RD TRISB
RD PORTB
Weak
Pull-up
RD PORTB
I/O pin
(1)
TTL
Input
Buffer
TRIS Latch
To INT0 or CCP
PORTB
TRISB