david1.asm

微机原理——接口应用编程源码

STACK SEGMENT STACK
DW 64 DUP(?)
STACK ENDS
DATA SEGMENT
TABLE DB 41H,44H,30H,38H,39H,3AH,49H,4EH,30H,20H,20H,00H
DATA ENDS
CODE SEGMENT
   ASSUME CS:CODE,DS:DATA
START:  MOV AX,DATA
        MOV DS,AX
        OUT 00H,AL
        CALL DALLY
        IN AL,00H

        MOV CH,AL
        ADD AL,0F0H
        MOV CL,04
        SHR AL,CL
        CMP AL ,09H
        JG A1
        CMP AL, 30H
        JMP A2
A1:     ADD AL,37H
A2:     MOV BX,OFFSET TABLE
        MOV AH,06H
        INT 10H
        MOV AH,01H
        INT 10H
        MOV AL,CH
        AND AL,0F0H
        CMP AL,09H
        JG A3
        ADD AL,30H
        JMP A4
A3:     ADD AL,37H
A4:     MOV AH,01H
        INT 10H
        JMP START      
DALLY:  PUSH AX
        MOV CX,0040H
A5:     MOV AX,056CH
A6:     DEC AX
        JNZ A6
        LOOP A5
        POP AX
        POP CX
        RET
    CODE ENDS
END START