xyorigin3.asm

80196kc系列单片机 循环显示4000h和4001h地址下低四位数据

rseg at 30h
numb equ 30h
check equ 32h
shu equ 34h
led equ 38h
shu2 equ 40h

cseg at 2000h
dcw t_over
cseg at 2080h
ld sp,#0f0h
ldb led,#0
ldb ioport1,led

ld shu,#4000h
ld shu2,#4001h
ldb ah,[shu]
ldb al,[shu]
ldb bh,[shu2]
ldb bl,[shu2]
ld dx,#1ch
andb ah,#11110000b
andb al,#00001111b
shrb ah,#4 ;obtain each 4 numbers
andb bh,#11110000b
andb bl,#00001111b
shrb bh,#4
ldb wsr,#0h;choose win 0
ldb int_mask,#00000001b
ldb ioc1,#00001000b
ldb ioc2,#2h
andb ioport2,#00111111b
ld t2,#48e4h

test: jbs ioport0,0,test
test2: jbc ioport0,0,test2
test3:jbs ioport0,0,test3

      ldb wsr,#01h
      ldb ioc3,#01h
      ldb wsr,#0h
      notb led
      ldb ioport1,led
      ldb ch,#00011111b
      ld numb,#90h
      ld check,#88h
      ei

exam1:jbc ioport0,2,exam1          
      di
      ldb ioport1,#00000000b
loop:sjmp loop
t_over:pushf
       ld t2,#48e4h
       djnz numb,exam2
back1:ld numb,#90h
      ld check,#88h
      ldb ch,#00011111b
      ld dx,#1ch
      popf
      ret
exam2:cmp numb,check
      je exam3
      ljmp back2
exam3:shrb ch,#1
      jc do1
      sjmp do2
do1:sub check,#8h
    notb led
    ldb ioport1,led
    sjmp back2     
do2:sub check,#18h
    ldb ioport1,[dx]
    add dx,#1h
back2:popf
      ret