100.asm

用8255新片连接输入输出电路,输入设备是一组(8)个开关

MY8255_A   EQU  9C60H
MY8255_B   EQU  9C61H
MY8255_C   EQU  9C62H
MY8255_M   EQU 9C63H
DATAS SEGMENT
X DB ?
DATAS ENDS
CODE  SEGMENT
   ASSUME  CS:CODE,DS:DATAS
START:
      MOV AX,DATAS
      MOV DS,AX
      MOV DX,MY8255_M
      MOV AL,82H
      OUT DX,AL
   A0:MOV DX,MY8255_B
       IN AL,DX
    MOV X,AL
      MOV DX,MY8255_A
      OUT DX,AL
      CALL DELAY
      XOR X,0FEH
       JZ CIRCUIT1
 MOV X,AL
      XOR X,0FDH
       JZ CIRCUIT2
MOV X,AL
XOR X,07EH
JZ CIRCUIT3
MOV X,AL
XOR X,0BDH
JZ CIRCUIT4
MOV X,AL
      XOR X,07FH
       JZ J5
MOV X,AL
      XOR X,0BFH
       JZ J6
JMP A0
CIRCUIT1:ROL AL,1
        MOV AH,AL
        MOV DX,MY8255_A
         OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
         CMP AL,0FEH
          JZ JUMP1
         JMP A0
         JUMP1:MOV AL,AH
         JMP CIRCUIT1
CIRCUIT2:MOV CL,2
ROL AL,CL
         MOV AH,AL
 MOV DX,MY8255_A
                OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
         CMP AL,0FDH
          JZ JUMP2
         JMP A0
         JUMP2:MOV AL,AH
         JMP CIRCUIT2
CIRCUIT3:   MOV AL, 0FEH
        MOV BL,07FH
C3:MOV CL,1
   ROL AL,CL
   ROR BL,CL
         MOV AH,AL
    MOV BH,BL
NOT BL
NOT AL
ADD AL,BL
NOT AL
 MOV DX,MY8255_A
               OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
         CMP AL,07EH
       JZ JUMP3
         JMP A0
         JUMP3:MOV AL,AH
MOV BL,BH
       JMP C3
J5:JMP  CIRCUIT5
J6:JMP CIRCUIT6
CIRCUIT4:MOV AL,0FDH
      MOV BL,0BFH
C4:   MOV CL,2
    ROL AL,CL
     ROR BL,CL
         MOV AH,AL
  MOV BH,BL
NOT BL
NOT AL
ADD AL,BL
NOT AL
 MOV DX,MY8255_A
               OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
         CMP AL,0BDH
       JZ JUMP4
         JMP A0
         JUMP4:MOV AL,AH
MOV BL,BH
       JMP C4
CIRCUIT5:ROR AL,1
        MOV AH,AL
        MOV DX,MY8255_A
         OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
         XOR AL,07FH
          JZ JUMP5
         JMP A0
   JUMP5:     MOV AL,AH
         JMP CIRCUIT5
CIRCUIT6:MOV CL,2
ROR AL,CL
        MOV AH,AL
        MOV DX,MY8255_A
         OUT DX,AL
         CALL DELAY
         MOV DX,MY8255_B
         IN AL,DX
        XOR AL,0BFH
          JZ JUMP6
         JMP A0
         JUMP6:MOV AL,AH
         JMP CIRCUIT6
DELAY:MOV CX,0FFFH
      D1:MOV DI,0FFFFH
      D2:DEC DI
         JNZ D2
        LOOP D1

        RET
   CODE  ENDS
          END START