ASSUME cs:mycode

mycode SEGMENT

mystart:
    MOV AX, 103h;
    MOV DS, AX
    MOV ES, AS
    MOV SI, 3;
    MOV DI, 4;

    MOV BL, 0;

    MOV CX, 255;
cycle:
    REPNE CMPSB
    CMP CX,0;
    JZ lastCmp:
    INC DH;
    jmp cycle;

lastCmp:
    MOV AL, DS:[SI]
    CMP ES:[DI], AL
    JNZ finalOut
    INC DH

finalOut:
    MOV AX, 4C00h
    INT 21H
mycode ENDS

END mystart