dv.bak

调节电位器

ST      BIT     P3.0
OE      BIT     P3.1
EOC     BIT     P3.2
        ORG     0000H
        AJMP    MAIN
        ORG     000BH
        AJMP    FT0
        ORG     0030H
MAIN:   MOV     SP,#6FH
        CLR     ST
        MOV     30H,#10
        MOV     31H,#10
        MOV     32H,#10
        MOV     33H,#10
        MOV     36H,#8
        MOV     TMOD,#01H
        MOV     TH0,#0
        MOV     TL0,#0
        MOV     IE,#82H
        SETB    TR0
LOOP:   JNB     20H.0,LP1
        CLR     20H.0
        ACALL   ADC
        ACALL   TRF
LP1:    ACALL   DISP
        AJMP    LOOP
FT0:    DJNZ    36H,FTH
        MOV     36H,#8
        SETB    20H.0
FTH:    RETI
ADC:    SETB    ST
        CLR     ST
        JNB     EOC,$
        CLR     OE
        MOV     A,P1
        MOV     26H,A
        SETB    OE
        RET
TRF:    MOV     A,26H
        MOV     B,#196
        MUL     AB
        MOV     R7,A
        MOV     R6,B
        ACALL   HB2
        MOV     A,R5
        ADD     A,R5
        DA      A
        MOV     R5,A
        MOV     A,R4
        ADDC    A,R4
        DA      A
        MOV     R4,A
        MOV     A,R3
        ADDC    A,R3
        DA      A
        MOV     R3,A
        MOV     30H,A
        MOV     A,R4
        ANL     A,#0F0H
        SWAP    A
        MOV     31H,A
        MOV     A,R4
        ANL     A,#0FH
        MOV     32H,A
        MOV     A,R5
        ANL     A,#0F0H
        SWAP    A
        MOV     33H,A
        RET
DISP:   MOV     A,#10H
        ORL     A,30H
        MOV     30H,A
        MOV     R0,#30H
        MOV     R2,#4
        MOV     R3,#01H
        MOV     DPTR,#DTAB
LPD:    MOV     A,@R0
        MOVC    A,@A+DPTR
        MOV     P0,A
        MOV     P2,R3
        ACALL   DELAY
        INC     R0
        MOV     A,R3
        RL      A
        MOV     R3,A
        DJNZ    R2,LPD
        RET
DTAB:   DB      03H,9FH,25H,0DH,99H
        DB      49H,41H,1FH,01H,09H
        DB      03H,0,0,0,0,0
        DB      02H,9EH,24H,0CH,98H
        DB      48H,40H,1EH,00H,08H
        DB      31H,0,0,0,0,0
HB2:	CLR	A
	MOV	R3,A
	MOV	R4,A
	MOV	R5,A
	MOV	R2,#10H
HB3:	MOV	A,R7
	RLC	A
	MOV	R7,A
	MOV	A,R6
	RLC	A
	MOV	R6,A
	MOV	A,R5
	ADDC	A,R5
	DA	A
	MOV	R5,A
	MOV	A,R4
	ADDC	A,R4
	DA	A
	MOV	R4,A
	MOV	A,R3
	ADDC	A,R3
	MOV	R3,A
	DJNZ	R2,HB3
	RET
DELAY:  MOV     R7,#0H
LDP:    NOP
        NOP
        DJNZ    R7,LDP
        RET