kbd.c

用于汇编领域的,运用于OS的MAIN函数.基于硬件基础的源代码

#include "hos.h"

/* Current shift state */
#define LEFT_SHIFT	0x01
#define RIGHT_SHIFT	0x02
#define LEFT_CTRL	0x04
#define RIGHT_CTRL	0x08
#define LEFT_ALT	0x10
#define RIGHT_ALT	0x20
#define SHIFT_MASK	(LEFT_SHIFT | RIGHT_SHIFT)
#define CTRL_MASK	(LEFT_CTRL | RIGHT_CTRL)
#define ALT_MASK	(LEFT_ALT | RIGHT_ALT)

/* Translate from scan code to key code, when shift is not pressed. */
static const keycode scan_table[] = {
	KEY_UNKNOWN, ASCII_ESC, '1', '2',	/* 0x00 ~ 0x03 */
	'3', '4', '5', '6',			/* 0x04 ~ 0x07 */
	'7', '8', '9', '0',			/* 0x08 ~ 0x0B */
	'-', '=', ASCII_BS, '\t',		/* 0x0C ~ 0x0F */
	'q', 'w', 'e', 'r',			/* 0x10 ~ 0x13 */
	't', 'y', 'u', 'i',			/* 0x14 ~ 0x17 */
	'o', 'p', '[', ']',			/* 0x18 ~ 0x1B */
	'\r', KEY_LCTRL, 'a', 's',		/* 0x1C ~ 0x1F */
	'd', 'f', 'g', 'h',			/* 0x20 ~ 0x23 */
	'j', 'k', 'l', ';',			/* 0x24 ~ 0x27 */
	'\'', '`', KEY_LSHIFT, '\\',		/* 0x28 ~ 0x2B */
	'z', 'x', 'c', 'v',			/* 0x2C ~ 0x2F */
	'b', 'n', 'm', ',',			/* 0x30 ~ 0x33 */
	'.', '/', KEY_RSHIFT, KEY_PRINTSCRN,	/* 0x34 ~ 0x37 */
	KEY_LALT, ' ', KEY_CAPSLOCK, KEY_F1,	/* 0x38 ~ 0x3B */
	KEY_F2, KEY_F3, KEY_F4, KEY_F5,		/* 0x3C ~ 0x3F */
	KEY_F6, KEY_F7, KEY_F8,	KEY_F9,		/* 0x40 ~ 0x43 */
	KEY_F10, KEY_NUMLOCK, KEY_SCRLOCK, KEY_KPHOME,	/* 0x44 ~ 0x47 */
	KEY_KPUP, KEY_KPPGUP, KEY_KPMINUS, KEY_KPLEFT,	/* 0x48 ~ 0x4B */
	KEY_KPCENTER, KEY_KPRIGHT, KEY_KPPLUS, KEY_KPEND,
	KEY_KPDOWN, KEY_KPPGDN, KEY_KPINSERT, KEY_KPDEL,
	KEY_SYSREQ, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
};

int key_entered;  // used to detect key press
#define SCAN_TABLE_SIZE		(sizeof(scan_table) / sizeof(keycode))

void kbd_isr(void);

static int convert(unsigned code)
{
	if(code > 0x80)
		return 0;

	if(code >= SCAN_TABLE_SIZE)
		return 0;

	return scan_table[code];
}

void kbd_handler(void)
{
	unsigned scancode, temp;

	scancode = inbyte(0x60);
	temp = convert(scancode);
	if(temp != 0)
			put_char(temp);

    key_entered=1; // used for wait_for_anykey()
	/* EOI */
	outbyte(0x20, 0x20);
}

void init_kbd(void)
{
	unsigned short irqmask;

	printk("[kernel] Initializing keyboard...\n");

	set_intr_gate(0x21, &kbd_isr);

	unmask_irq(1);
}

void wait_for_anykey(){
// if the user hits anykey, return
   key_entered=0;  // will become 1 inside kbd handler
   for(;;){
      if (key_entered==1) return;
   }
}