Question

编一个AT89s51单片机99 —00 秒的汇编程序,用两个独立数码管显示

Answer 1

ORG 0000H
LJMP MAIN
ORG 030H
MAIN:
MOV R2,#0FFH
MOV R5,#0AH
D0: INC R2
MOV R4,#64H
MOV R1,#0FFH
D1: MOV R3,#0FFH
INC R1
D2: MOV A,R1
DA A
MOV R1,A
ANL A,#0FH
ACALL CHA
MOV P2,#0EBH
ACALL DELAY
MOV A,R1
SWAP A
ANL A,#0FH
ACALL CHA
MOV P2,#0E7H
ACALL DELAY
MOV A,R2
ACALL CHA
MOV P2,#0E3H
ACALL DELAY
DJNZ R3,D2
DJNZ R4,D1
DJNZ R5,D0
LJMP MAIN

CHA: MOV DPTR,#TAB
MOVC A,@A+DPTR
MOV P0,A
RET
DELAY: MOV R6,#0FH
D4: MOV R7,#0FH
DJNZ R7,$
DJNZ R6,D4
RET
TAB: DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH
END
我的是000--999的，用38译码器控制数码管的3个共阴端，楼主自己修改一下吧！祝楼主好运了！

Answer 2

看看：

http://hi.baidu.com/do_sermon/item/5761e8896ef67fcfb071540c

Answer 3

倒计时啊，哈
可以联系我