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#include "../../interrupt_descriptor_table.h"
#include "../vga/text_mode_display.h"
#include "scancode_map.h"
extern void keyboard_handler(void);
extern char read_port(unsigned short port);
extern void write_port(unsigned short port, unsigned char data);
extern void load_idt(unsigned long *idt_ptr);
struct idt_entry keyboard_idt[256];
void init_keyboard_idt()
{
unsigned long keyboard_address;
unsigned long idt_address;
unsigned long idt_ptr[2];
// Build IDT entry
keyboard_address = (unsigned long) keyboard_handler;
keyboard_idt[0x21].offset_lowerbits = keyboard_address & 0xffff;
keyboard_idt[0x21].selector = 0x08; // Offset by 0x08
keyboard_idt[0x21].zero = 0;
keyboard_idt[0x21].type_attr = 0x8E; // Interrupt gate addr
keyboard_idt[0x21].offset_higherbits = (keyboard_address & 0xffff0000) >> 16;
idt_address = (unsigned long) keyboard_idt;
idt_ptr[0] = (sizeof(struct idt_entry) * 256) + ((idt_address & 0xffff) << 16);
idt_ptr[1] = idt_address >> 16;
// Init PIC 1 @ 0x20
write_port(0x20, 0x11);
write_port(0x21, 0x20);
write_port(0x21, 0x00);
write_port(0x21, 0x01);
write_port(0x21, 0xff);
// PIC 2 @ 0xA0
write_port(0xA0, 0x11);
write_port(0xA1, 0x28);
write_port(0xA1, 0x00);
write_port(0xA1, 0x01);
write_port(0xA1, 0xff);
load_idt(idt_ptr);
}
void init_keyboard_handler()
{
init_keyboard_idt();
write_port(0x21, 0xFD);
}
int isKeyup(int scancode)
{
return scancode & 0x80;
}
void handle_keypress() {
// Ack the interrupt
write_port(0x20, 0x20);
unsigned char scancode = read_port(0x60);
if(!isKeyup(scancode))
{
char pressed_key = scancode_map[scancode];
vga_print_raw(pressed_key);
}
}
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