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.global asm_pit_init
.global asm_pit_tick
.global asm_pit_get_ticks
ticks:
.int 0
asm_pit_get_ticks:
mov (ticks),%eax
ret
asm_pit_tick:
push %eax // persist
// INC TICK COUNTER
mov $ticks, %eax
incl (%eax)
pop %eax // load original
ret
asm_pit_init:
// configure ticking 25 times a second
// 1193180 / 25 = 47727.2
mov $47727, %dx
mov $0b00110100, %al
outb %al,$0x43
mov %dx,%ax
out %al, $0x40
xchg %ah,%al
out %al, $0x40
ret
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