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 WAIT &H3DA,8

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[[section .text]]
; ______________________________________________
;/                              \
;This is used to initialize the timer with a 100hz freq*
;so this generates a IRQ every 10 ms this means that at *
; every IRQ 10 ms are over so after 100 IRQs 1 second   *
;is over                                                         *
;\______________________________________________/
init_Timer:
 push   eax
   mov   al,0x36    ; control word 0011_0110b
   out   TIMER_CTRL_PORT,al
   mov   al,0x9C    ; count LSB
   out   TIMER_CNTR_0,al
   mov   al,0x2E    ; count MSB
   out   TIMER_CNTR_0,al;
 pop   eax
 ret

; ______________________________________________
;/                  \
; This is the IRQ handler             *
; At every call it increments the 'ticks' and if the 'ticks'   *
; is greater than 100 then means one second is over so   *
; increments the 'uptime' var            *
;\_______________________________________________/
TimerHandler:
 ISR_HEAD
   mov   eax,DATA_SEL
   mov   ds,eax
   inc   dword   [uptime]
 .end:
   mov al,0x20      ;EOI
   out 0x20,al
 ISR_TAIL
 iret

[[section .data]]
uptime   dd   0   ; up time incremented every IRQ

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#define    MILLISECONDS_PER_TICK   10
void delay(DWORD ms)
{
  DWORD end= uptime + (ms / MILLISECONDS_PER_TICK);
  while(uptime < end) 
              ;  
}