port.h File Reference

#include <stdint.h>

Include dependency graph for port.h:

Functions
uint8_t	port_byte_in (uint16_t port)
void	port_byte_out (uint16_t port, uint8_t value)
uint16_t	port_word_in (uint16_t port)
void	port_word_out (uint16_t port, uint16_t value)
uint32_t	port_dword_in (uint16_t port)
void	port_dword_out (uint16_t port, uint32_t value)

Detailed Description

See also

https://wiki.osdev.org/I/O_Ports

An I/O port is usually used as a technical term for a specific address on the x86's IO bus, which is used to communicate with devices without requiring memory access (alternative). This is the aim of this module.

Function Documentation

port_byte_in()

uint8_t port_byte_in

(

uint16_t

port

)

Reads a byte.

Parameters

port	a port number

Returns

the value for the port number

port_byte_out()

void port_byte_out	(	uint16_t	port,
		uint8_t	value )

Writes a byte to a port.

Parameters

port	a port number
value	the new value for the port

port_dword_in()

uint32_t port_dword_in

(

uint16_t

port

)

Reads a double word (4 bytes).

Parameters

port	a port number

Returns

the value for the port number

port_dword_out()

void port_dword_out	(	uint16_t	port,
		uint32_t	value )

Writes a double word to a port.

Parameters

port	a port number
value	the new value for the port

port_word_in()

uint16_t port_word_in

(

uint16_t

port

)

Reads a word (2 bytes).

Parameters

port	a port number

Returns

the value for the port number

port_word_out()

void port_word_out	(	uint16_t	port,
		uint16_t	value )

Writes a word to a port.

Parameters

port	a port number
value	the new value for the port