PIC16F87 Datasheet, PDF (68/214 Pages) Microchip Technology – 18/20/28-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology

PIC16F87/88
FIGURE 5-15:
BLOCK DIAGRAM OF RB7 PIN
PORT/Program Mode/ICD
PGD
1
Analog Input Mode
0
RBPU⁽²⁾
Data Bus
WR
PORTB
Data Latch
DQ
CK
TRIS Latch
DQ
WR
0
TRISB
CK
1
VDD
P
Weak
Pull-up
I/O pin⁽¹⁾
T1OSCEN
PGD DRVEN
RD TRISB
Set RBIF
RD PORTB
From Other
RB7:RB4 pins
T1OSCEN
Analog
Input Mode
TTL
Input Buffer
Latch
QD
EN
Q1
QD
RD PORTB
EN
Q3
PGD
To T1OSCI Input
To A/D Module Channel Input (PIC16F88 only)
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.
DS30487B-page 66
Preliminary
 2003 Microchip Technology Inc.