数字电压表的设计.asm

来自「基于Proteus的51系列单片机设计与仿真」· 汇编 代码 · 共 69 行

        DBUF1	equ	30H
	DBUF2	equ	31H
	DBUF3	equ	32H
	ABC	equ	35H
	ST	bit	P2.5
	EOC	bit	P2.6
	OE	bit	P2.7
	CLOCK	EQU	P2.4
	ORG	0000H
	AJMP	START
 	ORG	000BH
	AJMP	ST_T0
	ORG	0050H
START:	MOV	DBUF1,#00H
	MOV	DBUF2,#00H
        MOV	DBUF3,#00H
	MOV	DPTR,#TAB
	MOV	TMOD,#02H
	MOV	TH0,#245
	MOV	TL0,#00H
	MOV	IE,#82H
	SETB	TR0
WAIT:	CLR	ST	 
	SETB	ST	 
	CLR	ST
	JNB	EOC,$ 
	SETB	OE
	MOV	ABC,P1
	CLR	OE	 
	MOV	A,ABC
	MOV	B,#100
        DIV	AB
	MOV	DBUF3,A
	MOV	A,B
	MOV	B,#10
	DIV	AB
	MOV	DBUF2,A
	MOV	DBUF1,B
 	ACALL	L
	AJMP	WAIT
ST_T0:	CPL	CLOCK	 
	RETI 	 
L:	MOV	a,DBUF3
	MOVC	A,@A+DPTR	 
	CLR	P2.3
	MOV	P0,a
	ACALL	DELAY
	SETB	P2.3
	MOV	A,DBUF2
	MOVC	A,@A+DPTR
        CLR	P2.2
	MOV	P0,A
	ACALL	DELAY
	SETB	P2.2
	MOV	A,DBUF1
	MOVC	A,@A+DPTR	
	CLR	P2.1
	MOV	P0,A
	ACALL	DELAY
	SETB	P2.1
	RET
DELAY:	MOV	R7,#10
D:	MOV	R6,#250
 	DJNZ	R6,$
	DJNZ	R7,D
	RET
TAB:	DB  3fh,06h,5bh,4fh,66h,6dh,7dh,07h,7fh,6fh
	end