The PS/2 Keyboard interface code. More...

#include <basics.h>
#include <stdbool.h>
#include <hal.h>
#include <isr.h>

Include dependency graph for keyboard.h:

This graph shows which files directly or indirectly include this file:

Macros
#define	MOD_LCTRL 0b00000001
#define	MOD_RCTRL 0b00000010
#define	MOD_CTRL 0b00000011
#define	MOD_LSHIFT 0b00000100
#define	MOD_RSHIFT 0b00001000
#define	MOD_SHIFT 0b01001100
#define	MOD_LALT 0b00010000
#define	MOD_RALT 0b00100000
#define	MOD_ALT 0b00110000
#define	MOD_CAPSLOCK 0b01000000
#define	MOD_NUMLOCK 0b10000000
#define	CUR_UP -1
#define	CUR_DOWN -2
#define	CUR_LEFT -3
#define	CUR_RIGHT -4
#define	KB_BUFFER_SIZE 256

Functions
char	scancode_to_char (int scancode, bool uppercase)
	Converts the scancode to character.
void	keyboard_init ()
	Initalizes the RingBuffer to store the characters.
void	process_keyboard (InterruptFrame *frame)
	This is a function that is ran even when the sleep() function is called.
uint8_t	getmodifiers ()
	Gets the current modifiers (like lshift, rshift, etc.).
uint8_t	getc ()
	Gets the last pressed char.
int	getc_nonblock ()
	Non-blocking getc from keyboard buffer.
void	keyboard_flush_buffer (void)
	Clears pending keyboard input so stale keypresses are discarded.
int	handle_char_from_scancode (uint8_t data)
	Converts the scancode passed to it to ASCII characters.

Detailed Description

The PS/2 Keyboard interface code.

Author: Pradosh (prado.nosp@m.shga.nosp@m.me@gm.nosp@m.ail..nosp@m.com)

Version: 0.1

Date: 2026-03-20

Copyright: Copyright (c) Pradosh 2026

Definition in file keyboard.h.

Macro Definition Documentation

◆ CUR_DOWN

#define CUR_DOWN -2

Definition at line 32 of file keyboard.h.

◆ CUR_LEFT

#define CUR_LEFT -3

Definition at line 33 of file keyboard.h.

◆ CUR_RIGHT

#define CUR_RIGHT -4

Definition at line 34 of file keyboard.h.

◆ CUR_UP

#define CUR_UP -1

Definition at line 31 of file keyboard.h.

◆ KB_BUFFER_SIZE

#define KB_BUFFER_SIZE 256

Definition at line 36 of file keyboard.h.

◆ MOD_ALT

#define MOD_ALT 0b00110000

Definition at line 27 of file keyboard.h.

◆ MOD_CAPSLOCK

#define MOD_CAPSLOCK 0b01000000

Definition at line 28 of file keyboard.h.

◆ MOD_CTRL

#define MOD_CTRL 0b00000011

Definition at line 21 of file keyboard.h.

◆ MOD_LALT

#define MOD_LALT 0b00010000

Definition at line 25 of file keyboard.h.

◆ MOD_LCTRL

#define MOD_LCTRL 0b00000001

Definition at line 19 of file keyboard.h.

◆ MOD_LSHIFT

#define MOD_LSHIFT 0b00000100

Definition at line 22 of file keyboard.h.

◆ MOD_NUMLOCK

#define MOD_NUMLOCK 0b10000000

Definition at line 29 of file keyboard.h.

◆ MOD_RALT

#define MOD_RALT 0b00100000

Definition at line 26 of file keyboard.h.

◆ MOD_RCTRL

#define MOD_RCTRL 0b00000010

Definition at line 20 of file keyboard.h.

◆ MOD_RSHIFT

#define MOD_RSHIFT 0b00001000

Definition at line 23 of file keyboard.h.

◆ MOD_SHIFT

#define MOD_SHIFT 0b01001100

Definition at line 24 of file keyboard.h.

Function Documentation

◆ getc()

uint8_t getc ( )

Gets the last pressed char.

Returns: [uint8_t] Last scancode

◆ getc_nonblock()

int getc_nonblock ( )

Non-blocking getc from keyboard buffer.

Returns: int Character if available, 0 if no input

◆ handle_char_from_scancode()

int handle_char_from_scancode ( uint8_t data )

Converts the scancode passed to it to ASCII characters.

Parameters

data Scancode

Returns: int eqivalent of a character.

◆ scancode_to_char()

char scancode_to_char	(	int	scancode,
		bool	uppercase )

Converts the scancode to character.