27 lines
538 B
C++
27 lines
538 B
C++
#include "timer.h"
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uint32_t tick = 0;
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static void timer_callback (registers_t regs ){
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tick ++ ;
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kterm_writestring ("tick passed!");
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}
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void init_timer (uint32_t frequency){
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// register timer callback
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uint32_t divisor = 1193180 / frequency;
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// Send the commmand byte
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outb(0x43, 0x36);
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// Divisor has to be sent byt-wise , so will send lower then upper bytes
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uint8_t low = (uint8_t) (divisor & 0xFF);
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uint8_t high = (uint8_t) ((divisor >> 8) & 0xFF);
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outb(0x40, low);
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outb(0x40, high);
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} |