dianyabiao.txt

单片机实现的饿数字电压表单片机实现的饿数字电压表 单片机实现的饿数字电压表

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	；设定定时器0为方式2
	MOV	TH0,#245	
	MOV	TL0,#00H	
	MOV	IE,#82H	；打开总开关EA和ETO
	SETB	TR0	
WAIT:	CLR	ST	
	SETB	ST	
	CLR	ST	；启动A/D转换
	JNB	EOC,$	；等待转换结果
	SETB	OE	
	MOV	ADC,P1	
	CLR	OE	
	MOV	A,ADC	
	MOV	B,#100	
	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	；输出到LED
	LCALL	DELAY	
	SETB	P2.3	
	MOV	A,LED_1	
	MOVC	A,@A+DPTR	
	CLR	P2.2	
	ADD	A,#80H	
	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5ms
D1:	MOV	R7,#250	
        DJNZ	R7,$		
	DJNZ	R6,D1
        RET		
TABLE:	DB	3FH,06H,5BH,4FH,66H
	DB	6DH,7DH,07H,7FH,6FH
	END