本电路采用一片89C51、三片74HC164和六只PNP型三极管来驱动14只数码管,采用较低的成本获得了令人满意的大屏幕LED数码显示亮度,每个LED数码的笔段都采用了4只发发光二极管,两只串联后再双双并联,这样,可以在5V的低电压下,既有较高的亮度,又有较高的效率。

实际电路中,电源电压在3.6V时就可以点亮LED,4-5V时亮度已经令人满意!

org 00h
mov 30h,#2
mov 31h,#0
mov 32h,#0
mov 33h,#7
mov 34h,#0
mov 35h,#3
mov 36h,#1
mov 37h,#8
mov 38h,#6
mov 39h,#5
mov 3ah,#4
mov 3bh,#3
mov 3ch,#2
mov 3dh,#1

main:
call dip
call disp
jmp main

dip:
setb p0.4
setb p0.5
jb 51h,dip2
mov r0,#38h
mov r6,#0
fssj1:mov a,@r0
mov dptr,#tab0
movc a,@a+dptr
mov r7,#0
fs232:rlc a
mov p0.6,c
setb p0.7
clr p0.7
inc r7
cjne r7,#8,fs232
inc r0
inc r0
inc r6
cjne r6 ,#3,fssj1
clr p0.5
jmp dipend
dip2:
mov r0,#39h
mov r6,#0
fssj2:mov a,@r0
mov dptr,#tab0
movc a,@a+dptr
mov r7,#0
fs2322:rlc a
mov p0.6,c
setb p0.7
clr p0.7
inc r7
cjne r7,#8,fs2322
inc r0
inc r0
inc r6
cjne r6 ,#3,fssj2
clr p0.4
dipend:cpl 51h
ret

ys100:djnz 56h,$
ys200:djnz 57h,ys100
mov 57h,#10
ys300:djnz 58h,ys100
mov 58h,#100
cpl p1.3
ysend:ret

disp:
orl p0,#00001111b

inc 48h
mov a,48h
ds8:cjne a,#4,ds0
mov 48h,#0
mov a,48h

ds0:cjne a,#0,ds1
mov a,30h
mov dptr,#tabp2
movc a,@a+dptr
MOV P2,a

mov a,34h
mov dptr,#tabp1
movc a,@a+dptr
MOV P1,a

anl p0,#11110111b
jmp edisp

ds1:cjne a,#1,ds2
mov a,31h
mov dptr,#tabp2
movc a,@a+dptr
MOV P2,a

mov a,35h
mov dptr,#tabp1
movc a,@a+dptr
MOV P1,a

anl p0,#11111011b
jmp edisp

ds2:cjne a,#2,ds3
mov a,32h
mov dptr,#tabp2
movc a,@a+dptr
MOV P2,a

mov a,36h
mov dptr,#tabp1
movc a,@a+dptr
MOV P1,a

anl p0,#11111101b
jmp edisp

ds3:cjne a,#3,edisp
mov a,33h
mov dptr,#tabp2
movc a,@a+dptr
MOV P2,a

mov a,37h
mov dptr,#tabp1
movc a,@a+dptr
MOV P1,a

anl p0,#11111110b
edisp:ret

tab0:    DB 09H,0EBH,91H,0C1H
        DB 63H,45H,05H,0E9H
        DB 01H,41H,21H,07H
        DB 1DH,83H,15H,35H

tabp1:  DB 09H,0DBH,0A1H,0C1H
        DB 53H,45H,05H,0D9H
        DB 01H,41H,11H,07H
        DB 2DH,83H,25H,35H

tabp1a:  DB 09H,0EBH,91H,0C1H
        DB 63H,45H,05H,0E9H
        DB 01H,41H,21H,07H
        DB 1DH,83H,15H,35H
tabp2:   DB 21H,0B7H,0BH,07H
        DB 95H,45H,41H,37H
        DB 01H,05H,11H,0C1H
        DB 69H,83H,49H,59H

tabp2a:  DB 21H,0AFH,13H,07H
        DB 8DH,45H,41H,2FH
        DB 01H,05H,09H,0C1H
        DB 71H,83H,51H,59H

END