FreeFlyOS【七】：keyboard部分详解

keyboard.c

键盘驱动程序

#include "keyboard.h"
#include "../interrupt/trap.h"
#include "../vga/vga.h"
#include "../serial/serial.h"
/***** Keyboard input code *****/

#define NO              0

#define SHIFT           (1<<0)
#define CTL             (1<<1)
#define ALT             (1<<2)

#define CAPSLOCK        (1<<3)
#define NUMLOCK         (1<<4)
#define SCROLLLOCK      (1<<5)

#define E0ESC           (1<<6)

unsigned int shift=0;
char shell_input=0; //shell输入字符，每次读取一个
//int shell_rpos=0;      //shell输入缓冲区读偏移
//int shell_wpos=0;      //shell输入缓冲区写偏移
//shiftcode[1D]=CTL,
static unsigned char shiftcode[256] = {
    [0x1D] CTL,
    [0x2A] SHIFT,
    [0x36] SHIFT,
    [0x38] ALT,
    [0x9D] CTL,
    [0xB8] ALT
};

static unsigned char togglecode[256] = {
    [0x3A] CAPSLOCK,
    [0x45] NUMLOCK,
    [0x46] SCROLLLOCK
};

static unsigned char normalmap[256] = {
    NO,   0x1B, '1',  '2',  '3',  '4',  '5',  '6',  // 0x00
    '7',  '8',  '9',  '0',  '-',  '=',  '\b', '\t',
    'q',  'w',  'e',  'r',  't',  'y',  'u',  'i',  // 0x10
    'o',  'p',  '[',  ']',  '\n', NO,   'a',  's',
    'd',  'f',  'g',  'h',  'j',  'k',  'l',  ';',  // 0x20
    '\'', '`',  NO,   '\\', 'z',  'x',  'c',  'v',
    'b',  'n',  'm',  ',',  '.',  '/',  NO,   '*',  // 0x30
    NO,   ' ',  NO,   NO,   NO,   NO,   NO,   NO,
    NO,   NO,   NO,   NO,   NO,   NO,   NO,   '7',  // 0x40
    '8',  '9',  '-',  '4',  '5',  '6',  '+',  '1',
    '2',  '3',  '0',  '.',  NO,   NO,   NO,   NO,   // 0x50
    [0xC7] KEY_HOME,    [0x9C] '\n' /*KP_Enter*/,
    [0xB5] '/' /*KP_Div*/,  [0xC8] KEY_UP,
    [0xC9] KEY_PGUP,    [0xCB] KEY_LF,
    [0xCD] KEY_RT,      [0xCF] KEY_END,
    [0xD0] KEY_DN,      [0xD1] KEY_PGDN,
    [0xD2] KEY_INS,     [0xD3] KEY_DEL
};

static unsigned char shiftmap[256] = {
    NO,   033,  '!',  '@',  '#',  '$',  '%',  '^',  // 0x00
    '&',  '*',  '(',  ')',  '_',  '+',  '\b', '\t',
    'Q',  'W',  'E',  'R',  'T',  'Y',  'U',  'I',  // 0x10
    'O',  'P',  '{',  '}',  '\n', NO,   'A',  'S',
    'D',  'F',  'G',  'H',  'J',  'K',  'L',  ':',  // 0x20
    '"',  '~',  NO,   '|',  'Z',  'X',  'C',  'V',
    'B',  'N',  'M',  '<',  '>',  '?',  NO,   '*',  // 0x30
    NO,   ' ',  NO,   NO,   NO,   NO,   NO,   NO,
    NO,   NO,   NO,   NO,   NO,   NO,   NO,   '7',  // 0x40
    '8',  '9',  '-',  '4',  '5',  '6',  '+',  '1',
    '2',  '3',  '0',  '.',  NO,   NO,   NO,   NO,   // 0x50
    [0xC7] KEY_HOME,    [0x9C] '\n' /*KP_Enter*/,
    [0xB5] '/' /*KP_Div*/,  [0xC8] KEY_UP,
    [0xC9] KEY_PGUP,    [0xCB] KEY_LF,
    [0xCD] KEY_RT,      [0xCF] KEY_END,
    [0xD0] KEY_DN,      [0xD1] KEY_PGDN,
    [0xD2] KEY_INS,     [0xD3] KEY_DEL
};

#define C(x) (x - '@')

static unsigned char ctlmap[256] = {
    NO,      NO,      NO,      NO,      NO,      NO,      NO,      NO,
    NO,      NO,      NO,      NO,      NO,      NO,      NO,      NO,
    C('Q'),  C('W'),  C('E'),  C('R'),  C('T'),  C('Y'),  C('U'),  C('I'),
    C('O'),  C('P'),  NO,      NO,      '\r',    NO,      C('A'),  C('S'),
    C('D'),  C('F'),  C('G'),  C('H'),  C('J'),  C('K'),  C('L'),  NO,
    NO,      NO,      NO,      C('\\'), C('Z'),  C('X'),  C('C'),  C('V'),
    C('B'),  C('N'),  C('M'),  NO,      NO,      C('/'),  NO,      NO,
    [0x97] KEY_HOME,
    [0xB5] C('/'),      [0xC8] KEY_UP,
    [0xC9] KEY_PGUP,    [0xCB] KEY_LF,
    [0xCD] KEY_RT,      [0xCF] KEY_END,
    [0xD0] KEY_DN,      [0xD1] KEY_PGDN,
    [0xD2] KEY_INS,     [0xD3] KEY_DEL
};

static unsigned char *charcode[4] = {
    normalmap,
    shiftmap,
    ctlmap,
    ctlmap
};

/* *
 * kbd_proc_data - get data from keyboard
 *
 * The kbd_proc_data() function gets data from the keyboard.
 * If we finish a character, return it, else 0. And return -1 if no data.
 * */
int kbd_proc_data(void) {
    int c;
    unsigned char data;
    //static unsigned int shift=0;
   
    if ((inb(KBSTATP) & KBS_DIB) == 0) {
        return -1;
    }

    data = inb(KBDATAP);

    if (data == 0xE0) {
        // E0 escape character
        shift |= E0ESC;
        return 0;
    } else if (data & 0x80) {
        // Key released
        data = (shift & E0ESC ? data : data & 0x7F);
        shift &= ~(shiftcode[data] | E0ESC);
        return 0;
    } else if (shift & E0ESC) {
        // Last character was an E0 escape; or with 0x80
        data |= 0x80;
        shift &= ~E0ESC;
    }

    shift |= shiftcode[data];
    shift ^= togglecode[data];

    c = charcode[shift & (CTL | SHIFT)][data];
    if (shift & CAPSLOCK) {
        if ('a' <= c && c <= 'z')
            c += 'A' - 'a';
        else if ('A' <= c && c <= 'Z')
            c += 'a' - 'A';
    }
    //backspace
    //if (c=='\b'){
        //backtrace();
    //    return '\b';
    //}
    // Process special keys
    // Ctrl-Alt-Del: reboot
    if (!(~shift & (CTL | ALT)) && c == KEY_DEL) {
        printk("Rebooting!\b");
        outb(0x92, 0x3); // courtesy of Chris Frost
    }
    return c;
}

/* kbd_intr - try to feed input characters from keyboard */
void kbd_intr(void) {
    cons_intr(kbd_proc_data);
}

void kbd_init(void) {
    cons.rpos=0;
    cons.wpos=0;
    for(int i=0;i<CONSBUFSIZE;i++)
    {
        cons.buf[i]=0;
    }

    shell_input=0;
    // drain the kbd buffer
    shift=0;
    kbd_intr();
    pic_enable(IRQ_KBD);
}

Keyboard.h

#ifndef _KEYBOARD_H_
#define _KEYBOARD_H_

// Special keycodes
#define KEY_HOME            0xE0
#define KEY_END             0xE1
#define KEY_UP              0xE2
#define KEY_DN              0xE3
#define KEY_LF              0xE4
#define KEY_RT              0xE5
#define KEY_PGUP            0xE6
#define KEY_PGDN            0xE7
#define KEY_INS             0xE8
#define KEY_DEL             0xE9


/* This is i8042reg.h + kbdreg.h from NetBSD. */

#define KBSTATP             0x64    // kbd controller status port(I)
#define KBS_DIB             0x01    // kbd data in buffer
#define KBS_IBF             0x02    // kbd input buffer low
#define KBS_WARM            0x04    // kbd input buffer low
#define BS_OCMD             0x08    // kbd output buffer has command
#define KBS_NOSEC           0x10    // kbd security lock not engaged
#define KBS_TERR            0x20    // kbd transmission error
#define KBS_RERR            0x40    // kbd receive error
#define KBS_PERR            0x80    // kbd parity error

#define KBCMDP              0x64    // kbd controller port(O)
#define KBC_RAMREAD         0x20    // read from RAM
#define KBC_RAMWRITE        0x60    // write to RAM
#define KBC_AUXDISABLE      0xa7    // disable auxiliary port
#define KBC_AUXENABLE       0xa8    // enable auxiliary port
#define KBC_AUXTEST         0xa9    // test auxiliary port
#define KBC_KBDECHO         0xd2    // echo to keyboard port
#define KBC_AUXECHO         0xd3    // echo to auxiliary port
#define KBC_AUXWRITE        0xd4    // write to auxiliary port
#define KBC_SELFTEST        0xaa    // start self-test
#define KBC_KBDTEST         0xab    // test keyboard port
#define KBC_KBDDISABLE      0xad    // disable keyboard port
#define KBC_KBDENABLE       0xae    // enable keyboard port
#define KBC_PULSE0          0xfe    // pulse output bit 0
#define KBC_PULSE1          0xfd    // pulse output bit 1
#define KBC_PULSE2          0xfb    // pulse output bit 2
#define KBC_PULSE3          0xf7    // pulse output bit 3

#define KBDATAP             0x60    // kbd data port(I)
#define KBOUTP              0x60    // kbd data port(O)

#define K_RDCMDBYTE         0x20
#define K_LDCMDBYTE         0x60

#define KC8_TRANS           0x40    // convert to old scan codes
#define KC8_MDISABLE        0x20    // disable mouse
#define KC8_KDISABLE        0x10    // disable keyboard
#define KC8_IGNSEC          0x08    // ignore security lock
#define KC8_CPU             0x04    // exit from protected mode reset
#define KC8_MENABLE         0x02    // enable mouse interrupt
#define KC8_KENABLE         0x01    // enable keyboard interrupt
#define CMDBYTE             (KC8_TRANS|KC8_CPU|KC8_MENABLE|KC8_KENABLE)

/* keyboard commands */
#define KBC_RESET           0xFF    // reset the keyboard
#define KBC_RESEND          0xFE    // request the keyboard resend the last byte
#define KBC_SETDEFAULT      0xF6    // resets keyboard to its power-on defaults
#define KBC_DISABLE         0xF5    // as per KBC_SETDEFAULT, but also disable key scanning
#define KBC_ENABLE          0xF4    // enable key scanning
#define KBC_TYPEMATIC       0xF3    // set typematic rate and delay
#define KBC_SETTABLE        0xF0    // set scancode translation table
#define KBC_MODEIND         0xED    // set mode indicators(i.e. LEDs)
#define KBC_ECHO            0xEE    // request an echo from the keyboard

/* keyboard responses */
#define KBR_EXTENDED        0xE0    // extended key sequence
#define KBR_RESEND          0xFE    // needs resend of command
#define KBR_ACK             0xFA    // received a valid command
#define KBR_OVERRUN         0x00    // flooded
#define KBR_FAILURE         0xFD    // diagnosic failure
#define KBR_BREAK           0xF0    // break code prefix - sent on key release
#define KBR_RSTDONE         0xAA    // reset complete
#define KBR_ECHO            0xEE    // echo response

int kbd_proc_data(void);
void kbd_intr(void);
void kbd_init(void);

#endif

键盘驱动还是有点复杂的，话不多说，直接看图，自己理解，看完下面的原理，再对着代码看一看应该就OK了，驱动了解一下就行。

标签：NO,KBC,FreeFlyOS,kbd,详解,KEY,keyboard,data,define
来源： https://blog.csdn.net/cy295957410/article/details/112155475