#include <stdint.h> #include <_stdio.h> #include <interrupts.h> #include <ports.h> #include <task.h> #define PIT_A 0x40 #define PIT_CONTROL 0x43 #define PIT_MASK 0xFF #define PIT_SCALE 1193180 #define PIT_SET 0x36 #define CMD_BINARY 0x00 #define CMD_MODE0 0x00 #define CMD_MODE1 0x02 #define CMD_MODE2 0x04 #define CMD_MODE3 0x06 #define CMD_MODE4 0x08 #define CMD_MODE5 0x0a #define CMD_RW_BOTH 0x30 #define CMD_COUNTER0 0x00 #define CMD_COUNTER2 0x80 void setTimerFreq(uint32_t hz) { int divisor = PIT_SCALE / hz; outb(PIT_CONTROL, CMD_BINARY | CMD_MODE3 | CMD_RW_BOTH | CMD_COUNTER0); outb(PIT_A, (uint8_t) divisor); outb(PIT_A, (uint8_t) (divisor >> 8)); } uint64_t timer_ticks = 0; uint8_t timer_subticks = 0; void timerHandler() { printf("timer\n"); yields(); outb(0x20, 0x20); __asm__ volatile ("iret"); } void setupTimer() { printf("setting timer frequency to 100Hz\n"); setTimerFreq(100); setInterrupt(32, &timerHandler); }