外部按扭改变三位数字.txt

共有 45 个程序源码

        ORG  0000H   
          AJMP MAIN
          ORG  0003H          ;外部中断INT0入口地址  
          AJMP PINT0          ;转中断服务子程序
MAIN:   MOV SP,#40H    
        MOV  P1,#0FFH
        MOV  P2,#0FFH
        MOV  P0,#0FFH
        MOV  20H,#2
        MOV  21H,#1
        MOV  22H,#3
          SETB EA             ;开CPU中断
          SETB IT0            ;设定INT0触发方式
          SETB EX0            ;INT0请求中断
DSP:     JNB P3.1,JY

DSP1:     MOV DPTR,#TAB
  	  MOV A,21H
	  MOVC A,@A+DPTR
RX1:	  MOV P1,A
	  CLR P0.0
          DJNZ R7,RX1
          MOV R7,#0FFH
	  MOV P1,#0FFH
          SETB P0.0
	  MOV A,20H
	  MOVC A,@A+DPTR
RX2:	  MOV P1,A
	  CLR P0.1
          DJNZ R7,RX2
          SETB P0.1
          MOV R7,#0FFH
	  MOV P1,#0FFH
          SETB P0.1
	  MOV A,22H
	  MOVC A,@A+DPTR
RX3:	  MOV P1,A
	  CLR P0.2
          DJNZ R7,RX3
          SETB P0.2
          AJMP DSP
          RET
JY:       ACALL DL  ；延时20毫秒，消除接点抖动
          JNB P3.1,$
          INC 21H
          MOV R1,21H
          CJNE R1,#10,TZ
          MOV 21H,#0
          INC 20H
          MOV R1,20H
          CJNE R1,#10,TZ
          MOV 20H,#0
          INC 22H
          MOV R1,22H
          CJNE R1,#10,TZZ
          MOV 22H,#0          
TZ:       AJMP DSP
PINT0:    NOP
          CLR P2.4       
          INC 20H
          MOV R1,20H
          CJNE R1,#10,TZZ
          MOV 20H,#0
          INC 22H
          MOV R1,22H
          CJNE R1,#10,TZZ
          MOV 22H,#0          
TZZ:      NOP
          RETI

DL:	MOV R7,#100
DL1:	MOV R6,#100  
DL2:	DJNZ R6,DL2
	DJNZ R7,DL1
	RET

TAB: DB 60H,7DH,0D0H,58H,4DH;0/1/2/3/4/5/6/7/8/9/
     DB 4AH,42H,7CH,40H,48H

	END