MOV R7,A MOV LED_3,#00H MOV LED_2,#00H MOV A,#00H LOOP1: ADD A,#20H ;一位二进制码对应20MV电压值
DA A JNC
LOOP2
MOV R4,A INC LED_2 MOV A,LED_2 CJNE A,#0AH,LOOP4 MOV LED_2,#00H INC LED_3
LOOP4: MOV A,R4 LOOP2: DJNZ R7,LOOP1 ACALL BTOD1 LCALL DISP SJMP WAIT ORG 200H BTOD1: MOV R6,A ANL
A,#0F0H
MOV R5,#4 LOOP3: RR A
DJNZ R5,LOOP3
MOV LED_1,A MOV A,R6 ANL A,#0FH
MOV LED_0,A
RET
INT_T0: CPL
CLOCK
RETI
DISP: MOV A,LED_0 MOVC A,@A+DPTR CLR
P2.3
;提供0809时钟信号
;显示子程序
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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 MOV A,LED_3 MOVC A,@A+DPTR CLR
P2.0
MOV P0,A LCALL DELAY SETB P2.0 RET
DELAY: MOV R6,#10 D1:
MOV R7,#250
DJNZ R7,$ DJNZ R6,D1 RET TABLE: DB END
3FH,06H,5BH,4FH,66H ;共阴数码管7段值
DB 6DH,7DH,07H,7FH,6FH
;延时5MS
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