luciaos/kbd.c

109 lines
2.5 KiB
C

#include "interrupt.h"
#include "kbd.h"
uint8_t scancodesToAscii[0x3B] =
"\0\0" // 0x00 - 0x01
"1234567890" // 0x02 - 0x0B
"-=" // 0x0C - 0x0D
"\0\0" // 0x0E - 0x0F
"qwertyuiop[]" // 0x10 - 0x1B
"\0\0" // 0x1C - 0x1D
"asdfghjkl;'`" // 0x1E - 0x29
"\0" // 0x2A
"\\zxcvbnm,./" // 0x2B - 0x35
"\0" // 0x36
"*" // 0x37
"\0" // 0x38
" " // 0x39
"\0"; // 0x3A
uint8_t scancodesToAsciiShift[0x3B] =
"\0\0" // 0x00 - 0x01
"!@#$%^&*()" // 0x02 - 0x0B
"_+" // 0x0C - 0x0D
"\0\0" // 0x0E - 0x0F
"QWERTYUIOP{}" // 0x10 - 0x1B
"\0\0" // 0x1C - 0x1D
"ASDFGHJKL:\"~" // 0x1E - 0x29
"\0" // 0x2A
"|ZXCVBNM<>?" // 0x2B - 0x35
"\0" // 0x36
"*" // 0x37
"\0" // 0x38
" " // 0x39
"\0"; // 0x3A
uint8_t _KBDWAIT;
uint8_t _KEYCAPS = 0, _KEYSHIFT = 0;
uint8_t _LSTKEY_ASCII = 0, _LSTKEY_SCAN = 0;
__attribute__ ((interrupt))
void keyboardHandler(struct interrupt_frame *frame) {
uint16_t old_ds;
asm volatile(
"mov %%ds, %%bx\n"
"mov $0x10, %%ax\n"
"mov %%ax, %%ds\n"
:"=b"(old_ds)::"%ax"
);
uint8_t key;
asm volatile("inb $0x60, %%al":"=a"(key));
if (key == 0x3A) { // caps lock press
_KEYCAPS = !_KEYCAPS;
} else if (key == 0x2A || key == 0x36) { // left and right shift press
_KEYSHIFT = 1;
} else if (key == 0xAA || key == 0xB6) { // left and right shift release
_KEYSHIFT = 0;
} else if (key < 0x3B) {
uint8_t ascii = _KEYCAPS != _KEYSHIFT ?
scancodesToAsciiShift[key] :
scancodesToAscii[key];
if (ascii) {
_LSTKEY_ASCII = ascii;
_LSTKEY_SCAN = key;
_KBDWAIT = 1;
}
} else {
_LSTKEY_ASCII = 0;
_LSTKEY_SCAN = key;
}
asm volatile("outb %%al, $0x20"::"a"(0x20));
asm volatile(
"mov %%ax, %%ds\n"
::"a"(old_ds)
);
}
__attribute((__no_caller_saved_registers__))
void kbd_clear() {
_KBDWAIT = 0;
_LSTKEY_ASCII = 0;
_LSTKEY_SCAN = 0;
}
__attribute((__no_caller_saved_registers__))
void kbd_wait() {
_KBDWAIT = 0;
while(!_KBDWAIT) {
asm volatile("hlt");
}
}
__attribute((__no_caller_saved_registers__))
uint8_t get_key() {
while(!_LSTKEY_ASCII) {
asm volatile("hlt");
}
uint8_t k = _LSTKEY_ASCII;
_LSTKEY_ASCII = 0;
return k;
}
__attribute((__no_caller_saved_registers__))
uint16_t get_scancode() {
while(!_LSTKEY_SCAN) {
asm volatile("hlt");
}
uint16_t k = _LSTKEY_SCAN | (_LSTKEY_ASCII << 8);
_LSTKEY_SCAN = 0;
_LSTKEY_ASCII = 0;
return k;
}