Intel 8XC251SA - Page 125

7-3
INPUT/OUTPUT PORTS
Figure 7-1. Port 1 and Port 3 Structure
Figure 7-2. Port 0 Structure
Read
Latch
Read
Pin
Write to
Latch
Internal
Bus
Alternate
Output
Function
D
CL
Q
Q#
P3. x 
Latch
Internal
Pullup
P3. x
Alternate
Input
Function
A2239-01
V
CC
Read
Latch
Read
Pin
Address/
Data
Control
D
CL
Q
Q#
P0. x

A2238-01
V
CC
Write to
Latch
Internal
Bus
P0.
x 
Latch
1
0