Datasheet

Table Of Contents
PIC18F1220/1320
DS39605F-page 94 © 2007 Microchip Technology Inc.
FIGURE 10-11: BLOCK DIAGRAM OF RB4/AN6/RX/DT/KBI0 PIN
Data Bus
WR LATB or
WR TRISB
Data Latch
TRIS Latch
RD TRISB
QD
Q
CK
QD
EN
DT Data
1
0
QD
Q
CK
RD PORTB
RB4 pin
PORTB
RD LATB
RBPU
(2)
P
Weak
Pull-up
Q1
From other
QD
EN
Set RBIF
RB7:RB4 pins
RD PORTB
Q3
To A/D Converter
EUSART Enabled
TTL
Input
Buffer
Note 1: I/O pins have diode protection to V
DD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s) and clear the RBPU
bit (INTCON2<7>).
DT TRIS
Analog Input Mode
RX/DT Input
Analog Input
Mode
Schmitt
Trigger
VDD