S3C84E5/C84E9/P84E9

I/O PORTS

 

 

9 I/O PORTS

OVERVIEW

The S3C84E5/C84E9/P84E9 microcontroller has seven bit-programmable I/O ports, P0–P4. This gives a total of 36 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 S3C84E5/C84E9/P84E9 I/O port functions.

 

Table 9-1. S3C84E5/C84E9/P84E9 Port Configuration Overview

 

 

Port

Configuration Options

 

 

0

Bit programmable port; input or output mode selected by software; input or push-pull output. Software

 

assignable pull-up resistor.

 

Alternately, P0.0–P0.7 can be used as I/O for Timer A, Timer 1(0,1). P0.0 and P0.1 can alternately be

 

used for subsystem oscillator in/out mode selected by software

 

 

1

Bit programmable port; input or output mode selected by software; input or push-pull output. Software

 

assignable pull-up resistor.

 

Alternatively, P1.0–P1.5 can be used as Timer A, Timer 1(0), UART, Watch Timer Buzzer output

 

 

2

Bit programmable port; input or output mode selected by software; input or push-pull output. Software

 

assignable pull-up.

 

Alternately, P2.0–P2.7 can be used as inputs for external interrupts INT0–INT7. (with noise filters and

 

interrupt controller)

 

 

3

Bit programmable port; input or output mode selected by software; input or push-pull output. Software

 

assignable pull-up.

 

Alternately, P3.0–P3.7 can be used as analog inputs for A/D converter modules.

 

 

4

Bit programmable port; input or output mode selected by software; input or push-pull output. Software

 

assignable pull-up.

 

Alternatively, P4.0–P4.5 can be used as Timer B, inputs for external interrupts INT8–INT10. (with noise

 

filters and interrupt controller)

 

 

9-1

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Samsung user manual O Ports, S3C84E5/C84E9/P84E9 Port Configuration Overview, Port Configuration Options