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#include<types.h>
#include<asm.h>
#include<stdio.h>
void add_idt_entry(size_t num,uint32_t offset);
uint32_t tick=0;
const uint32_t TICKS_PER_SECOND=50;
extern uint32_t time;
uint32_t time=0;
void timer_handler()
{
tick++;
if(tick==TICKS_PER_SECOND)
{
//printf("%d seconds passed\n",time);
tick=0;
time++;
}
ioport_out(0x20, 0x20);
ioport_out(0xa0,0x20);
}
void init_timer(uint32_t frequency)
{
// Firstly, register our timer callback.
// The value we send to the PIT is the value to divide it's input clock
// (1193180 Hz) by, to get our required frequency. Important to note is
// that the divisor must be small enough to fit into 16-bits.
uint32_t divisor = 1193180 / frequency;
// Send the command byte.
ioport_out(0x43, 0x36);
// Divisor has to be sent byte-wise, so split here into upper/lower bytes.
uint8_t l = (uint8_t)(divisor & 0xFF);
uint8_t h = (uint8_t)( (divisor>>8) & 0xFF );
// Send the frequency divisor.
ioport_out(0x40, l);
ioport_out(0x40, h);
}
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