digital voltmeter.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

LED_0	EQU 	30H
LED_1 	EQU 	31H
LED_2 	EQU 	32H			   	;存放段码
ADC		EQU		35H
CLOCK	BIT		P2.4			;定义ADC0808时钟位
ST 		BIT 	P2.5
EOC 	BIT 	P2.6
OE 		BIT 	P2.7

		ORG 	00H
		SJMP	START
		ORG		0BH
		LJMP	INT_T0

START:	MOV		LED_0,#00H
		MOV		LED_1,#00H
		MOV		LED_2,#00H
		MOV		DPTR,#TABLE		;段码表首地址
		MOV		TMOD,#02H
		MOV		TH0,#245
		MOV		TL0,#00H
		MOV		IE,#82H
		SETB	TR0

WAIT: 	CLR 	ST			  	
		SETB 	ST
		CLR 	ST				;启动AD转换
 		JNB 	EOC,$			;等待转换结束
		SETB 	OE 
		MOV 	ADC,P1			;读取AD转换结果
		CLR 	OE		
		MOV 	A,ADC
		MOV 	B,#100			;AD转换结果转换成BCD码
		DIV 	AB
		MOV 	LED_2,A
		MOV 	A,B
		MOV 	B,#10
		DIV 	AB
		MOV 	LED_1,A
		MOV 	LED_0,B
		LCALL	DISP
		SJMP 	WAIT

INT_T0:	CPL		CLOCK		 	;提供ADC0808时钟信号
		RETI

DISP:	MOV		A,LED_0			;显示子程序
		MOVC	A,@A+DPTR
		CLR		P2.3
		MOV		P0,A
		LCALL	DELAY
		SETB	P2.3

		MOV		A,LED_1
		MOVC	A,@A+DPTR
		CLR		P2.2
		MOV		P0,A
		LCALL	DELAY
		SETB	P2.2

		MOV		A,LED_2
		MOVC	A,@A+DPTR
		CLR		P2.1
		MOV		P0,A
		LCALL	DELAY
		SETB	P2.1
		RET

DELAY:	MOV		R6,#10			;延时5毫秒
D1:		MOV		R7,#250
		DJNZ	R7,$
		DJNZ	R6,D1
		RET

TABLE: 	DB 		3FH,06H,5BH,4FH,66H
		DB 		6DH,7DH,07H,7FH,6FH
		END