
S3C828B/F828B/C8289/F8289/C8285/F8285
I/O PORTS
9-1
9
I/O PORTS
OVERVIEW
The S3C828B/F828B/C8289/F8289/C8285/F8285 microcontroller has nine bit-programmable I/O ports, P0–P8.
The port 1 is a 7-bit port, the port 3 is a 6-bit port, the port 7 is a 4-bit port, and the others are 8-bit ports. This
gives a total of 65 I/O pins. Each port can be flexibly configured to meet application design requirements. The
CPU accesses ports by directly writing or reading port registers. No special I/O instructions are required.
Table 9-1 gives you a general overview of the S3C828B/F828B/C8289/F8289/C8285/F8285 I/O port functions.
Table 9-1. S3C828B/F828B/C8289/F8289/C8285/F8285 Port Configuration Overview
Port
Configuration Options
0
1-bit programmable I/O port.
Schmitt trigger input or push-pull open-drain output mode selected by software; software assignable pull-ups.
P0.0–P0.7 can be used as inputs for external interrupts INT0–INT7
(with noise filter, interrupt enable and pending control).
1
1-bit programmable I/O port.
Schmitt trigger input or push-pull, open-drain output mode selected by software; software assignable pull-ups.
Alternately P1.0–P1.6 can be used as T1CAP, T1CLK, T1OUT, T1PWM, BUZ, SO, SCK, SI.
2
1-bit programmable I/O port.
Input or push-pull output mode selected by software; software assignable pull-ups. Alternatively P2.0-P2.7 can be
used as AD0–AD7/V
BLDREF.
3
1-bit programmable I/O port.
Input or push-pull output mode selected by software; software assignable pull-ups.
Alternately P3.0–P3.5 can be used as TBPWM, TAOUT/TAPWM, TACLK, TACAP, TxD, RxD or LCD SEG.
4
1-bit programmable I/O port.
Input or push-pull, open drain output mode selected by software; software assignable pull-ups.
P4.0–P4.7 can alternately be used as outputs for LCD SEG.
5
1-bit programmable I/O port.
Input or push-pull, open drain output mode selected by software; software assignable pull-ups.
P5.0–P5.7 can alternately be used as outputs for LCD SEG.
6
1-bit programmable I/O port.
Input or push-pull output mode selected by software; software assignable pull-ups.
P6.0–P6.7 can alternately be used as outputs for LCD SEG.
7
1-bit programmable I/O port.
Input or push-pull output mode selected by software; software assignable pull-ups.
P7.0–P7.3 can alternately be used as outputs for LCD SEG.
8
1-bit or 2-bit or 4-bit programmable I/O port.
Input or push-pull, open drain output mode selected by software; software assignable pull-ups.
P8.0–P8.7 can alternately be used as outputs for LCD COM/SEG.