;       MOV     DX,303H     ;CONTROL REG ADDRESS
;       MOV     AL,80H      ;ALL PORTS AS OUTPUT
;       OUT     DX,AL
        MOV     DX, 378H
        MOV     AL, 80H
        CALL    MDEConfigPort
;AGAIN: MOV     DX,300H
;       MOV     AL,55H
;       OUT     DX,AL
AGAIN:  MOV     DX, 378H
        MOV     AL, 55H
        CALL    MDEOutPA
        CALL    QSDELAY     ;1/4 SEC DELAY
;       MOV     AL,0AAH     ;TOGGLE BIT
;       OUT     DX,AL
        MOV     AL, 0AAH
        CALL    MDEOutPA
        CALL    QSDELAY
        MOV     AH,01
        INT     16H         ;CHECK KEYPRESS
        JZ      GAIN        ;PRESS ANY KEY TO EXIT
        MOV     AH,4CH
        INT     21H         ;EXIT

QSDELAY PROC    NEAR
        MOV     CX,16572    ;16,572x15.085 usec=1/4 sec 
        PUSH    AX
W1:     IN      AL,61H
        AND     AL,00010000B  
        CMP     AL,AH
        JE      W1
        MOV     AH,AL
        LOOP    W1
        POP     AX
        RET
QSDELAY ENDP