PIC16F819T-E Datasheet, PDF (54/176 Pages) Microchip Technology – 18/20-Pin Enhanced Flash Microcontrollers with nanoWatt Technology

PIC16F818/819
FIGURE 5-15:
BLOCK DIAGRAM OF RB7 PIN
Port/Program Mode/ICD
PGD
1
0
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⁾
0
1
T1OSCEN
PGD DRVEN
RD TRISB
Set RBIF
RD PORTB
From other
RB7:RB4 pins
PGD
To T1OSI Input
T1OSCEN
Analog
Input Mode
TTL
Input Buffer
Latch
QD
EN
Q1
QD
RD PORTB
EN
Q3
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.
DS39598E-page 52
 2004 Microchip Technology Inc.