rm2.asm

微机原理——接口应用编程源码

STACK SEGMENT STACK
      DW 64 DUP(?)
STACK ENDS
DATA SEGMENT
     TABLE1 DB 4EH,6FH,72H,6DH,61H,6CH,3AH,20H,20H,00H
     TABLE2 DB 41H,6CH,61H,72H,6DH,3AH,20H,20H,20H,00H
DATA ENDS
CODE SEGMENT
   ASSUME CS:CODE,DS:DATA
START:  MOV AX,DATA
        MOV DS,AX

        MOV AL,82H
        OUT 63H,AL         ;8255
        MOV AL,00H
        OUT 60H,AL

A0:     OUT 00H,AL
        CALL DALLY
	IN AL,00H
       
      
	MOV CH,AL
       ; ADD AL,0F0H
        CMP AL,80H
        JA  A7
        
        MOV AL,00H
        OUT 60H,AL     ;set 8255 value:00H
        JMP A8

A7:     MOV AL,03H
        OUT 60H,AL    ;set 8255  value:03H
        
       
A8:     MOV AL,CH
        MOV CL,04
        SHR AL,CL
        CMP AL,09H
        JA A1
        ADD AL, 30H
        JMP A2
A1:     ADD AL,37H
A2:     
        CMP CH,80H
	JA  A3
        MOV BX,OFFSET TABLE1
        JMP A4
A3:	MOV BX,OFFSET TABLE2
A4:     MOV AH,06H
        INT 10H
        MOV AH,01H
        INT 10H
        MOV AL,CH
        AND AL,0FH
        CMP AL,09H
        JA A5
	ADD AL,30H
        JMP A6
A5:     ADD AL,37H
A6:     MOV AH,01H
        INT 10H
        CALL DALLY
        MOV AX,010DH
        INT 10H
        MOV AL,CH
        JMP START     
DALLY:  PUSH CX
        PUSH AX
        MOV CX,00FFH
M1:     MOV AX,0000H
        PUSH CX
        MOV CX,00FFH
M2:     MOV AX,0000H
        LOOP M2
        POP CX
        LOOP M1
        POP AX
        POP CX
        RET
    CODE ENDS
    END START