Next Previous Contents

# Linux I/O port programming mini-HOWTO

## Author: Riku Saikkonen `<Riku.Saikkonen@hut.fi>`

v3.0, 2000-12-13

This HOWTO document describes programming hardware I/O ports and waiting for small periods of time in user-mode Linux programs running on the Intel x86 architecture.

## 1. Introduction

## 2. Using I/O ports in C programs

- 2.1 The normal method
- 2.2 An alternate method: `/dev/port`

## 3. Interrupts (IRQs) and DMA access

## 4. High-resolution timing

- 4.1 Delays
- 4.2 Measuring time

## 5. Other programming languages

## 6. Some useful ports

- 6.1 The parallel port
- 6.2 The game (joystick) port
- 6.3 The serial port

## 7. Hints

## 8. Troubleshooting

## 9. Example code

## 10. Credits

Next Previous Contents