led.asm

Protues仿真的一个数码管电路.用了ULN2003和373.只能是一个基本电路.供学习.

		ORG		0030H
		AJMP	MAIN
MAIN:	MOV		P0,#00H
		MOV		P1,#00H
		MOV		P2,#00H
		MOV		DPL,#00H
		MOV		DPH,#00H
		CLR		RS0
		CLR		RS1;选择第0组寄存器
START:	MOV	78H,#00H
		MOV	79H,#02H
		MOV	7AH,#01H
		LCALL	LEDSHOW;
		LJMP	START
		RET

LEDSHOW:PUSH	ACC;
		MOV	R0,#78H;78H为数字寄存器.
		MOV	A,@R0
		MOV	DPTR,#LEDDB
		MOVC	A,@A+DPTR;
		MOV	P0,A
		MOV	R1,#79H;79H为位寄存器
		MOV	P2,#0FH
;		MOV	P0,#7AH;7AH为小数点寄存器
		LCALL	DELAY;	
		POP	ACC
		RET
DELAY:	MOV	R6,#64H
L1:		MOV	R7,#61H
		DJNZ	R7,$
		DJNZ	R6,L1;
		RET
LEDDB:	DB	3FH,06H,5BH,4FH,74H,75H,7DH,71H,7FH,77H
		END