8_查询式键盘.asm

单片机杭州天煌教仪自带例程单片机杭州天煌教仪自带例程

   ;查询式键盘
   ;P2口--键盘
   ;  ===================
       ORG 0000H
       LJMP MAIN
       ORG 0030H
       DBUF  EQU  30H
       TEMP  EQU  40H
       DIN   BIT  P3.6
       CLK   BIT  P3.7
       
START:  MOV   30H,#16H
MAIN:  ACALL DISP
       ACALL KEY
       AJMP  MAIN

KEY:   MOV P2,#0FFH
       MOV A,P2
       CJNE A, #0FFH, K00
       AJMP KEY
K00:   ACALL DELAY
       MOV A,P2
       CJNE A,#0FFH,K01
       AJMP KEY
K01:   MOV R3,#8
       MOV R2,#0
       MOV B,A
       MOV DPTR,#K0TAB
K02:   MOV A,R2
       MOVC A,@A+DPTR
       CJNE A,B,K04
K03:   MOV A,P2
       CJNE A,#0FFH,K03
       ACALL DELAY
       MOV A,R2
       RET
K04:   INC R2
       DJNZ R3,K02
       MOV A,#0FFH
       AJMP  KEY
K0TAB: DB 0FEH,0FDH,0FBH,0F7H
       DB 0EFH,0DFH,0BFH,07FH

DISP: MOV DBUF,A
      MOV DBUF+1,#16
      MOV DBUF+2,#16
      MOV DBUF+3,#16
      MOV DBUF+4,#16
     
      MOV   R0,  #DBUF
      MOV   R1,  #TEMP
      MOV   R2,  #5
 DP10:MOV   DPTR,#SEGTAB
      MOV   A,   @R0
      MOVC  A,   @A+DPTR
      MOV   @R1, A
      INC   R0
      INC   R1
      DJNZ  R2,  DP10
      MOV   R0,  #TEMP
      MOV   R1,  #5
 DP12:MOV   R2,  #8
      MOV   A,   @R0
 DP13:RLC   A
      MOV   DIN,C;DIN, C
      CLR   CLK
      SETB  CLK   ;
      DJNZ  R2,  DP13
      INC   R0
      DJNZ  R1,  DP12

       RET

SEGTAB:DB    3FH,06H,5BH,4FH,66H,6DH
       DB    7DH,07H,7FH,6FH,77H,7CH
       DB    58H,5EH,79H,71H,00H,40H

DELAY: MOV   R4,   #02H
AA1:   MOV   R5,   #0F8H
AA:    
       NOP
       NOP
       DJNZ  R5,   AA
       DJNZ  R4,   AA1
       RET

       END









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