Why int 21h/ ah=0Ah doesn't work in emu86 [closed]

Question

I've written a simple code to get a student information like name and ID, but in the code when I want to get input the interrupt doesn't work I mean int 21h/ah=0Ah It pauses when the interrupt is reached but just accepts Enter from keyboard not any number or characters, here my code :

stack segment 

    dw 128 dup (?)

stack ends

data segment 


    name0 db 30,?,30 dup('$')
    id0 db 10,?,10 dup('$') 

    menu db "1-Enter student name:",0Dh,0Ah
    db "2-Enter student ID:",0Dh,0Ah
    db "3-Printing the student name and ID:",0Dh,0Ah,
    db "4-Exit",0Dh,0Ah
    db "Please Select :",'$'



    selection db 1,?,4

    show0 db "(s)he is ",'$'
    show1 db " his/her ID ",'$'

   ; address1 db 2 dup(?)
   ; address2 db 2 dup(?)



data ends    


code segment
start:
; set segment registers:
    mov ax, data
    mov ds, ax
    ;mov ax, data1
    mov es, ax

    push bp
    mov bp,sp              

    xor cx,cx

loop1:
    ;cx is reserved

    push offset menu
    call print

    lea dx,selection   
    mov ah,0Ah
    int 21h         ; <----- doesn't work 

    lea bx,selection
    mov cl,[bx+2]

    cmp cl,1
    je getname_scope

    cmp cl,2
    je getid_scope

    cmp cl,3
    je showinfo


ret0:           

    cmp cl,4
    jne loop1
    jmp exit

            getname_scope:

                mov bx, offset name0
                push bx
                call Get

            jmp ret0

            getid_scope:

                lea bx,id0
                push bx
                call Get    

            jmp ret0   

            showinfo:

                push offset show0
                call print

                push offset name0+2
                call print

                push offset show1
                call print 

                push offset id0+2
                call print



            jmp ret0

exit:   

    ; wait for any key....    
    mov ah, 1
    int 21h

    pop bp

    mov ax, 4c00h ; exit to operating system.
    int 21h    

code ends


proc Get near

    push bp
    mov bp,sp

    lea dx,[bp+4]
    mov ah,0Ah
    int 21h


    pop bp
    ret

Get endp



proc print near

    push bp
    mov bp,sp

    mov dx,[bp+4]
    mov ah, 9
    int 21h

    pop bp
  ret     

end start ; set entry point and stop the assembler.

what's wrong with the code ? how to

Answer 1

The problem is in your declaration of "selection". Your buffer is only one character large, which is enough space for only the Enter key. To accept more characters, you have to increase the size of the buffer.