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assemblyinputmasm

Basic Input assembly Language

Hey I have started learning assembly language.

I wrote the following code:

.MODEL SMALL
.STACK 1000H
.DATA
MSG db "Hey$"
.CODE
MAIN PROC
    MOV AX, @DATA
    MOV DS, AX

    MOV AH,0AH ; setting the sub function
    MOV DX, offset msg ; moving address of msg to dx
    INT 21h     ; calling interrupt

    MOV AH, 09
    MOV DX, OFFSET MSG
    INT 21h     ; for printing

    MOV AH, 04Ch    ; Select exit function
    MOV AL, 00  ; Return 0
    INT 21h     ; Call Interupt to Terminate program
MAIN ENDP
END MAIN

I am trying to take input, it is working kind of but when I try printing it I do not get the proper string. I used this list to select the interrupt function.

I am attaching a screenshot, I have given input the following string:

Hey this is me taking input

But I got unexpected result.

Screenshot:

enter image description here

Questions:

  • What am I doing wrong here?
  • Is there a nice debugger to use when writing assembly programs?
  • Any links to good assembly tutorials would be very nice?

Thanks.

Solution

  • You didn't set aside enough space for your input string; when you "declared" MSG, you gave it room for only 4 characters ("Hey$").