error

.MODEL  SMALL
.STACK  100H
.CODE

START:
    MOV    AX, 00H
    MOV    BX, 4H
    MOV    CX, 0*0H

AGAIN:
    ADD    CX, AX
    DEC    BX
    JZ     DONE
    JMP    AGAIN

DONE:
    MOV    AX, 0*0
    MOV    BX, 0*0

    MOV    AL, 4H

    MOV    AH, 4CH
    INT    21H

END START