3.2.asm

开关控制8个灯的亮灭

        org     4000h
        ljmp    main
        org     001bh
        ljmp    ivt
        org     4300h
main:   mov     r7,#07h
        mov     r2,#18h
        mov     r6,#0
        mov     a,#01h
        mov     p1,a
        mov     tmod,#10h
        mov     th1,#18h
        mov     tl1,#9ch
        setb    tr1
        setb    ea
        setb    et1
wait:   sjmp    wait
ivt:    cjne    r6,#0,next2
next1:  rl      a
        mov     p1,a
        djnz    r7,lf
        mov     r7,#07h
        mov     r6,#01h
lf:     mov     r1,a
        mov     a,r2
        add     a,#20h
        mov     r2,a
        mov     th1,a
        mov     a,r1
        ljmp    lr
next2:  rr      a
        mov     p1,a
        djnz    r7,rh
        mov     r7,#07h
        mov     r6,#00h
rh:     mov     r1,a
        mov     a,r2
        clr     c
        subb    a,#20h
        mov     r2,a
        mov     a,r1
        mov     th1,r2
lr:     mov     tl1,#9ch
        setb    tr1
        reti
        end