16号中断读键盘输入SHIFT退出

16号中断读键盘输入SHIFT退出

L_SHIFT = 00000010B
R_SHIFT = 00000001B
CODE SEGMENT
    ASSUME CS:CODE
START:
    MOV AH,2
    INT 16H
    TEST AL,L_SHIFT + R_SHIFT
    JNZ OVER
    MOV AH,1
    INT 16H
    JZ START
    MOV AH,0
    INT 16H
    MOV DL,AL
    MOV AH,2
    INT 21H
    JMP START
OVER:
    MOV AH,4CH
    INT 21H    
CODE ENDS
END START