Z51F3220FNX Datasheet, PDF (73/312 Pages) Zilog, Inc. – Z8051 Series 8-Bit Microcontrollers

Z51F3220
Product Specification
9.6 P3 Port
9.6.1 P3 Port Description
P3 is 8-bit I/O port. P3 control registers consist of P3 data register (P3), P3 direction register (P3IO) and P3
pull-up resistor selection register (P3PU). Refer to the port function selection registers for the P3 function
selection.
9.6.2 Register description for P3
P3 (P3 Data Register) : 98H
7
6
5
4
3
2
P37
P36
P35
P34
P33
P32
R/W
R/W
R/W
R/W
R/W
R/W
P3[7:0]
I/O Data
P3IO (P3 Direction Register) : C1H
7
6
5
P37IO
P36IO
P35IO
R/W
R/W
R/W
4
P34IO
R/W
3
P33IO
R/W
2
P32IO
R/W
P3IO[7:0]
P3 Data I/O Direction
0
Input
1
Output
P3PU (P3 Pull-up Resistor Selection Register) : AFH
7
6
5
4
P37PU
P36PU
P35PU
P34PU
R/W
R/W
R/W
R/W
3
P33PU
R/W
2
P32PU
R/W
P3PU[7:0]
Configure Pull-up Resistor of P3 Port
0
Disable
1
Enable
1
0
P31
P30
R/W
R/W
Initial value : 00H
1
P31IO
R/W
0
P30IO
R/W
Initial value : 00H
1
P31PU
R/W
0
P30PU
R/W
Initial value : 00H
PS029902-0212
PRELIMINARY
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