shiyan1.asm

大学时学汇编做的一些小实验

CODES SEGMENT
    ASSUME CS:CODES
START:
    MOV AH,01H
    INT 21H
    CMP AL,'a'
    JB RET
    CMP AL,'z'
    ja ret
    SUB AL,20H
    MOV DL,AL
    MOV AH,02H
    INT 21H
    jmp start
    ret:
    MOV AH,4CH
    INT 21H
CODES ENDS
    END START