PIC18F1220_07 Datasheet, PDF (93/308 Pages) Microchip Technology – 18/20/28-Pin High-Performance, Enhanced Flash Microcontrollers with 10-bit A/D and nanoWatt Technology

PIC18F1220/1320
FIGURE 10-8:
BLOCK DIAGRAM OF RB1/AN5/TX/CK/INT1 PIN
EUSART Enable
TX/CK Data
TX/CK TRIS
RBPU⁽²⁾
Analog Input Mode
Data Bus
WR LATB
or
PORTB
WR TRISB
Data Latch
DQ
CK
TRIS Latch
DQ
CK
RD TRISB
RD LATB
RD PORTB
1
0
VDD
P
Weak
Pull-up
RB1 pin⁽¹⁾
TTL
Input
Buffer
Q
D
EN
INT1/CK Input
Schmitt
Trigger
Input
Buffer
RD PORTB
Analog Input
Mode
To A/D Converter
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 (INTCON2<7>).
© 2007 Microchip Technology Inc.
DS39605F-page 91