Holtek HT-IDE, Руководство пользователя

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mov a,10h ; setup delay time
call delays ;(8) ; call delays subroutine
mov a,00000011b ; move acc=00000011,
; (BUSY=0, ACK=0, OE=1, WR=1)
mov pc,a ; output acc to port C
mov a,7 ; setup delay time
call delays ; call delays subroutine
mov a,00000111b ; move acc=00000111,
; (BUSY=0, ACK=1, OE=1, WR=1)
mov pc,a ; output acc to port C
mov a,5 ; setup delay time
call delays ; call delays subroutine
mov a,00000011b ; move acc=00000011,
; (BUSY=0, ACK=0, OE=1, WR=1)
mov pc,a ;(9) ; output acc to port C
mov a,5 ; setup delay time
call delays ; call delays subroutine
clr tmr ; clear timer
set tmrc.4 ;(10) ; setup timer control reg. start
; counting
mov a,00001011b ; move acc=00001011,
; (BUSY=1, ACK=0, OE=1, WR=1)
mov pc,a ;(11) ; output acc to port C
clr acc ; clear acc
store1: ; store1
snz acc.0 ;(4) ; check if acc.0=“0” .if external
; INT
; interrupt, will change acc.0=“1”
jmp store1 ; if “0” jump storel
clr tmrc.4 ; set timer control reg. stop
; counting
snz acc.3 ;(12) ; check acc.3=1 (acc.3=“1” timer
; time-out , acc.3=“0” external INT)
jmp next ; if not 1 jump next
jmp top ; acc.3=1 jump top
delays proc ; delay subroutine
d1: ; d1
sdz acc ;
jmp d1 ;
ret ;
delays endp ;
end ;
Program description
The program begins (1) by setting up the interrupt control. The external
interrupt and timer/counter are enabled and the timer/counter is setup to
be an internal type. Section (2) sets Port A and B to be inputs and Port C to
Chapter 17 Parallel Port
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