42 lines
588 B
C
42 lines
588 B
C
#include <system.h>
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void
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timer_phase(
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int hz
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) {
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int divisor = 1193180 / hz;
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outportb(0x43, 0x36);
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outportb(0x40, divisor & 0xFF);
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outportb(0x40, (divisor >> 8) & 0xFF);
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}
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long timer_ticks = 0;
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unsigned long ticker = 0;
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void
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timer_handler(
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struct regs *r
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) {
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++timer_ticks;
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#if 0
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if (timer_ticks % 18 == 0) {
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++ticker;
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}
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#endif
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switch_task();
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}
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void timer_install() {
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irq_install_handler(0, timer_handler);
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timer_phase(100); /* 100Hz */
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}
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void
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timer_wait(
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int ticks
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) {
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long eticks;
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eticks = (long)timer_ticks + (long)ticks;
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while(timer_ticks < eticks);
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}
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