keyboard.c

一个小型的操作系统,采用gcc进行开发,几千行的代码,方便初学者学习

/*
*  Snixos Project version 1.0, 2003.6
*  (C) Copyright 2003,2004,2005 Jockeyson,KeqiangGao <[e-mail]>
*  All Rights Reserved.
*  Distributed under the terms of the GNU General Public License.
*
*  This program is a free and open source software and you can redistribute 
*  it and/or modify it under the terms of the GNU General Public License as
*  published by the Free Software Foundation. As no any liability is assumed 
*  for any incidental or consequential damages in connection with the 
*  information or program fragments contained herein,so any exception arised
*  is at your own risk. It is ABSOLUTELY WITHOUT ANY WARRANTY.
*  Bug report please send to [e-mail] .
*/
/*
  keyboard.c: keyboard interrupt handler in C
  Author  : [e-mail]
  Time    : 2004.3
  $Id: keyboard.c,v 1.3 2004/06/11 22:42:56 root Exp root $
  built   : $Date: 2004/06/11 22:42:56 $
  $Revision: 1.3 $
*/

#include "keyboard.h"
#include "io.h"
#include "stdio.h"
#include "keybd.h"

/*
keyBdHandle() 
	read keyboard and store scancode and ascii code to keyboard queue, lit up 
	keyboard LEDS when capsLock,numLock,scrollLock alternated ,etc...
*/
void keyBdHandle()
{
    unsigned char scanCode;

    scanCode = inb(KBDATAPORT);
    switch (scanCode) {		/* function and control key */
    case 1:
	printf("<Esc>");
	goto bye;
	break;
    case 59:
	printf("<F1>");
	goto bye;
	break;
    case 60:
	printf("<F2>");
	goto bye;
	break;
    case 61:
	printf("<F3>");
	goto bye;
	break;
    case 62:
	printf("<F4>");
	goto bye;
	break;
    case 63:
	printf("<F5>");
	goto bye;
	break;
    case 64:
	printf("<F6>");
	goto bye;
	break;
    case 65:
	printf("<F7>");
	goto bye;
	break;
    case 66:
	printf("<F8>");
	goto bye;
	break;
    case 67:
	printf("<F9>");
	goto bye;
	break;
    case 68:
	printf("<F10>");
	goto bye;
	break;
    case 87:
	printf("<F11>");
	goto bye;
	break;
    case 88:
	printf("<F12>");
	goto bye;
	break;

    case 0x2a:			/* left shift pressed */
	ks.LeftShift = PRESSED;
	goto bye;
	break;
    case 0x36:			/* right shift pressed */
	ks.RightShift = PRESSED;
	goto bye;
	break;
    case 0xaa:			/* left shift released */
	ks.LeftShift = RELEASED;
	goto bye;
	break;
    case 0xb6:			/* right shift released */
	ks.RightShift = RELEASED;
	goto bye;
	break;
    case 0x1d:			/* left Ctrl pressed */
	ks.LeftCtrl = PRESSED;
	goto bye;
	break;
    case 0x9d:			/* left ctrl released */
	ks.LeftCtrl = RELEASED;
	goto bye;
	break;
    case 0x38:			/* left Alt pressed */
	ks.LeftAlt = PRESSED;
	goto bye;
	break;
    case 0xb8:			/* Left Alt released */
	ks.LeftAlt = RELEASED;
	goto bye;
	break;

    case 58:			/* alternate CapsLock bit */
	kbdLEDS = kbdLEDS ^ 4;
	kbdLedOnOff(kbdLEDS);
	ks.CapsLock = (ks.CapsLock + 1) % 2;
	goto bye;
	break;
    case 69:			/* alternate NumLock bit */
	kbdLEDS = kbdLEDS ^ 2;
	kbdLedOnOff(kbdLEDS);
	ks.NumLock = (ks.NumLock + 1) % 2;
	goto bye;
	break;
    case 70:			/* alternate ScrollLock bit */
	kbdLEDS = kbdLEDS ^ 1;
	kbdLedOnOff(kbdLEDS);
	ks.ScrollLock = (ks.ScrollLock + 1) % 2;
	goto bye;
	break;

    case 0xe0:			/* extended scanCode */
	ks.ScanExtE0 = 1;
	goto bye;
	break;

    }

    if (ks.ScanExtE0 == 1) {	/* e0 1c e0 9c */
	switch (scanCode) {
	case 0x1d:		/* RightCtrl pressed */
	    ks.RightCtrl = PRESSED;
	    break;
	case 0x9d:		/* RightCtrl released */
	    ks.RightCtrl = RELEASED;
	    break;
	case 0x38:		/* RightAlt pressed */
	    ks.RightAlt = PRESSED;
	    break;
	case 0xb8:		/* RightAlt released */
	    ks.RightAlt = RELEASED;
	    break;
	case 0x1c:		/* Enter on keypad */
	    ks.ScanExtE0 = 0;
	    goto sendToBuffer;
	    break;
	case 0x35:		/* / on keypad */
	    goto sendToBuffer;
	    break;

	case 82:		/* Insert  */
	case 83:		/* Delete */
	case 71:		/* Home  */
	case 79:		/* End  */
	case 73:		/* PageUp */
	case 81:		/* PageDown */
	case 72:		/* Up */
	case 75:		/* Left */
	case 80:		/* Down */
	case 77:		/* Right */
	    ks.ScanExtE0 = 0;
	    goto sendToBuffer;
	    break;
	}

	ks.ScanExtE0 = 0;
	goto bye;
    }

    if ((ks.NumLock != LOCKED)) {
	switch (scanCode) {
	case 82:
	    printf("<Insert>");
	    goto bye;
	    break;
	case 83:
	    printf("<Delete>");
	    goto bye;
	    break;
	case 71:
	    printf("<Home>");
	    goto bye;
	    break;
	case 79:
	    printf("<End>");
	    goto bye;
	    break;
	case 73:
	    printf("<PageUp>");
	    goto bye;
	    break;
	case 81:
	    printf("<PageDown>");
	    goto bye;
	    break;
	case 72:
	    printf("<Up>");
	    goto bye;
	    break;
	case 75:
	    printf("<Left>");
	    goto bye;
	    break;
	case 80:
	    printf("<Down>");
	    goto bye;
	    break;
	case 77:
	    printf("<Right>");
	    goto bye;
	    break;
	}
    }
    if ((ks.NumLock == LOCKED) && (ks.ScanExtE0 == 0)) {
	/* enable keypad */
	switch (scanCode) {
	case 71:		/*ch='7'; */
	    scanCode = 8;
	    break;
	case 72:		/*ch='8'; */
	    scanCode = 9;
	    break;
	case 73:		/*ch='9'; */
	    scanCode = 10;
	    break;
	case 75:		/*ch='4'; */
	    scanCode = 5;
	    break;
	case 76:		/*ch='5'; */
	    scanCode = 6;
	    break;
	case 77:		/*ch='6'; */
	    scanCode = 7;
	    break;
	case 79:		/*ch='1'; */
	    scanCode = 2;
	    break;
	case 80:		/*ch='2'; */
	    scanCode = 3;
	    break;
	case 81:		/*ch='3'; */
	    scanCode = 4;
	    break;
	case 82:		/*ch='0'; */
	    scanCode = 11;
	    break;
	case 83:		/*ch='.'; */
	    scanCode = 0x34;
	    break;
	}

    } else {			/* disable keypad */
	switch (scanCode) {
	case 82:
	    printf("<Insert>");
	    goto bye;
	    break;
	case 83:
	    printf("<Delete>");
	    goto bye;
	    break;
	case 71:
	    printf("<Home>");
	    goto bye;
	    break;
	case 79:
	    printf("<End>");
	    goto bye;
	    break;
	case 73:
	    printf("<PageUp>");
	    goto bye;
	    break;
	case 81:
	    printf("<PageDown>");
	    goto bye;
	    break;
	case 72:
	    printf("<Up>");
	    goto bye;
	    break;
	case 75:
	    printf("<Left>");
	    goto bye;
	    break;
	case 80:
	    printf("<Down>");
	    goto bye;
	    break;
	case 77:
	    printf("<Right>");
	    goto bye;
	    break;
	}
    }


  sendToBuffer:
    if (scanCode >= 0x80)	/* released or pressed (bit7=0 means pressed) */
	goto bye;

    if ((keyTail + 1) % KBSIZE == keyHead) {
	printf("keyboard buffer full\n");
	goto bye;
    }

    keybdTail->scan = scanCode;
    keybdTail->ascii = (ks.LeftShift == PRESSED
			|| ks.RightShift == PRESSED
			|| ks.CapsLock ==
			LOCKED) ? shiftMap[scanCode] : ascTab[scanCode];
    moveTail();

  bye:
    /*  send reset signal to keyboard */
    scanCode = inb(KBCTRLPORT);
    scanCode || 0x80;
    outb(scanCode, KBCTRLPORT);
    scanCode = inb(KBCTRLPORT);
    scanCode && 0x7f;
    outb(scanCode, KBCTRLPORT);

    /*  send EOI to 8259  */
    outb(0x20, 0x20);		/* EOI , without this keyborad may hang up! */
}

static void moveHead()
{
    keyHead = (keyHead + 1) % KBSIZE;
}

static void moveTail()
{
    keyTail = (keyTail + 1) % KBSIZE;
}

/*  if keyborad buffer emtpy then return 1, else return 0 */
int keyEmpty()
{
    return ((keyHead % KBSIZE) == keyTail ? 1 : 0);
}

/*  return ascii key */
char getKey()
{
    char a;
    while (1) {
	if (!keyEmpty())
	    break;
    }
    a = keybdHead->ascii;
    moveHead();
    return a;
}

/*  return scan key  */
char getScan()
{
    char a;
    while (1) {
	if (!keyEmpty())
	    break;
    }
    a = keybdHead->scan;
    moveHead();
    return a;
}

/*  return both ascii and scan key */
void readKeybd(char *ascii, char *scan)
{
    while (1) {
	if (!keyEmpty())
	    break;
    }
    *ascii = keybdHead->ascii;
    *scan = keybdHead->scan;
    moveHead();
}

/* return 1 pressed, return 0 released */
int getLeftCtrl(){
  return ks.LeftCtrl;
}

/*  port 60h b0 is ScrollLock, b1 is NumLock, b2 is CapsLock */
void kbdLedOnOff(unsigned char i)
{
    unsigned int a = 0;
    outb(0xed, 0x60);
    while (a < 0xfffff) 
	a++;	/* delay */
    outb(i & 7, 0x60);
}