【文件属性】：
文件名称：用汇编程序编写秒表的程序
文件大小：1KB
文件格式：ASM
更新时间：2014-04-20 14:32:41
汇编
timer_value equ 30h
disp_h equ 31h
disp_l equ 32h
timer_cs equ 33h
org 0000h
ajmp main
org 000bh
ajmp time0
org 0030h
main:
acall init
loop: mov a,timer_value
cjne a,#60,next
mov timer_value,#0
next: acall disp
ajmp loop
init: mov tmod,#01h
mov th0,#3ch
mov tl0,#0b0h
setb tr0
setb et0
setb ea
setb p3.3
setb p3.2
mov timer_value,#0
mov disp_h,#0
mov disp_l,#0
mov timer_cs,#20
time0:
clr tr0
mov th0,#3ch
mov tl0,#0b0h
djnz timer_cs,time0_end
mov timer_cs,#20
inc timer_value
time0_end:
setb tr0
reti
dmzh: mov a,timer_value
mov b,#10
div ab
mov disp_h,a
mov disp_l,b
ret
disp:
acall dmzh
mov dptr,#tab
mov a,disp_h
movc a,@a+dptr
cpl a
mov p1,a
clr p3.3
acall delay
setb p3.3
mov dptr,#tab
mov a,disp_l
movc a,@a+dptr
cpl a
mov p1,a
clr p3.2
acall delay
setb p3.2
ret
delay:
mov r3,#10
del2: mov r4,#250
del1: djnz r4,del1
djnz r3,del2
ret
tab: db 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH,77H,7CH,39H,5EH,79H,71H
end