.model small

.data

prompt   db 'Iveskite sesioliktaini skaiciu: $'
result   db 10,'Dvejetaineje sistemoje tai yra: $'

N0 db "0000 $"
N1 db "0001 $"
N2 db "0010 $"
N3 db "0011 $"
N4 db "0100 $"
N5 db "0101 $"
N6 db "0110 $"
N7 db "0111 $"
N8 db "1000 $"
N9 db "1001 $"

A db "1010 $"
B db "1011 $"
C db "1100 $"
D db "1101 $"
E db "1110 $"
F db "1111 $"

hex      db 50 dup(?)

.code

mov ax, @data
mov ds, ax

mov dx,offset prompt
mov ah,9h
int 21h

mov bx,offset hex
take_input:
    mov ah,1h
    int 21h
    cmp al,13
    jne add_symbol
    inc bx
    mov [bx],0
    jmp display_result_prompt

add_symbol:
    mov byte ptr [bx],al
    inc bx
    jmp take_input

display_result_prompt:
    mov dx,offset result
    mov ah,9h
    int 21h


mov bx,offset hex
process:
    mov dl,byte ptr [bx]
    cmp dl,0
    je finish
    call convert
    inc bx
    jmp process

finish:
    mov ax, 4c00h
    int 21h

convert:
    cmp dl,"A"
    je typeA
    cmp dl,"B"
    je typeB
    cmp dl,"C"
    je typeC
    cmp dl,"D"
    je typeD
    cmp dl,"E"
    je typeE
    cmp dl,"F"
    je typeF
    cmp dl,"0"
    je typeN0
    cmp dl,"1"
    je typeN1
    cmp dl,"2"
    je typeN2
    cmp dl,"3"
    je typeN3
    cmp dl,"4"
    je typeN4
    cmp dl,"5"
    je typeN5
    cmp dl,"6"
    je typeN6
    cmp dl,"7"
    je typeN7
    cmp dl,"8"
    je typeN8
    cmp dl,"9"
    je typeN9
    ret

typeE:
    mov ah,9
    mov dx,offset E
    int 21h
    ret
typeA:
    mov ah,9
    mov dx,offset A
    int 21h
    ret
typeB:
    mov ah,9
    mov dx,offset A
    int 21h
    ret
typeC:
    mov ah,9
    mov dx,offset C
    int 21h
    ret
typeD:
    mov ah,9
    mov dx,offset D
    int 21h
    ret
typeF:
    mov ah,9
    mov dx,offset F
    int 21h
    ret

typeN0:
    mov ah,9
    mov dx,offset N0
    int 21h
    ret
typeN1:
    mov ah,9
    mov dx,offset N1
    int 21h
    ret
typeN2:
    mov ah,9
    mov dx,offset N2
    int 21h
    ret
typeN3:
    mov ah,9
    mov dx,offset N3
    int 21h
    ret
typeN4:
    mov ah,9
    mov dx,offset N4
    int 21h
    ret
typeN5:
    mov ah,9
    mov dx,offset N5
    int 21h
    ret
typeN6:
    mov ah,9
    mov dx,offset N6
    int 21h
    ret
typeN7:
    mov ah,9
    mov dx,offset N7
    int 21h
    ret
typeN8:
    mov ah,9
    mov dx,offset N8
    int 21h
    ret
typeN9:
    mov ah,9
    mov dx,offset N9
    int 21h
    ret