led display.asm

Proteus在MCS-51％26ARM7系统中的应用百例 Proteus在MCS-51％26ARM7系统中的应用百例

DISP_CNT	EQU		30H
TCNT		EQU		31H
		ORG		00H
		SJMP	START
		ORG		0BH
		LJMP	INT_T0
START:	MOV		DISP_CNT,#00H
		MOV		TCNT,#00H
		MOV		P2,#00H
		MOV		TMOD,#01H
		MOV		TH0,#(65536-5000)/256
		MOV		TL0,#(65536-5000)MOD 256
		MOV		IE,#82H
		SETB	TR0

DISP:	MOV		A,DISP_CNT					;段码组号	
		MOV		DPTR,#TABLE
		MOV		R0,P2						;读取位选信息
		ADD		A,R0						;得到偏移地址
		MOVC	A,@A+DPTR
		MOV		P0,A						;取出段码显示
		LJMP	DISP

INT_T0:	MOV		TH0,#(65536-5000)/256
		MOV		TL0,#(65536-5000)MOD 256		
		INC		P2							;数码管位选信号
		MOV		A,P2
		CJNE	A,#08H,RETUNE				;已扫描一次?
		MOV		P2,#00H
		INC		TCNT						;扫描次数加1
		MOV		A,TCNT
		CJNE	A,#10,RETUNE				;一组数已显示0.4秒?
		MOV		TCNT,#00H
		INC		DISP_CNT					;段码组号加1
		MOV		A,DISP_CNT
		CJNE	A,#15,RETUNE				;所有段码组都已显示?
		MOV		P2,#00H
		MOV		DISP_CNT,#00H
		MOV		TCNT,#00H
RETUNE:	RETI

TABLE:	DB		00H,00H,00H,00H,00H,00H,00H
		DB		06H,5BH,4FH,66H,6DH,7DH,07H,7FH
		DB		00H,00H,00H,00H,00H,00H,00H,00H

		END