;read a number in decimal, convert it to hex and print it on the fuckin screen

assume cs:code, ds: data

data segment
    nrten db 10,10 dup(?)
    lten db ?
    nr dw ? ; the number in base ten
    temp dw ?
    invhex db 10 dup (?)
    hextable db "0123456789ABCDEF"
    result db 10 dup (?)
    newline db 10,13,'$'
data ends

code segment
    start:
        mov ax,data
        mov ds,ax

        ;read the number in decimal
        mov ah,0Ah
        mov dx,offset nrten
        int 21h

        mov al, nrten[1]
        mov lten,al
        ;mov si,lten
        ;mov nrten[si+1],'$'

        mov cl, lten ;move the length of the string in cx
        mov ch,0


        mov temp,1
        dec cx

        mulme:
            ; multiply temp with 10
            mov ax,temp
            mov dx,10
            mul dx ; ax := temp * 10
            mov temp,ax
        loop mulme

        ;now we have the power of then corresponding to the length of the string

        mov si,2
        mov nr,0
        mov cl, lten ;move the length of the string in cx
        mov ch,0

        repme:
            sub nrten[si],'0'

            mov ax,temp ; temp can be 1,10,100 ... whatever
            mul nrten[si] ; ax := nrten[si] * ax

            add nr,ax  ;add the new digit to the number

            ; divide temp with 10
            mov ax,temp
            mov dl,10
            div dl ; al := temp / 10
            mov temp,ax
            inc si

        loop repme

        ;we should have the number in nr
        ;convert the bitch to hexa

        mov si,0

        convertme:

            mov ax,nr
            mov dl,16
            div dl ; al := nr / 16 ah = nr mod 16
            mov dl,al ; store the quotient, we will need it

            lea bx,hextable
            mov al,ah
            xlat

            ;al now has the ASCII hex digit
            ;we put it in a string (we'll invert it later)

            mov invhex[si],al
            inc si

            ;we still have the quotient in dl
            ;we overwrite the number with it
            mov dh,0
            mov nr,dx

            cmp nr,0
            jne convertme

        ;now invert the invhex string and get this over with
        ;we have it's length in si

        dec si
        mov cx,si
        inc cx; si goes from 0
        mov di,0

        invertme:
            mov al,invhex[si]
            mov result[di],al
            dec si
            inc di
        loop invertme

        mov result[di],'$'

        ;print newline

        mov ah,09h
        lea dx, newline
        int 21h

        ;print it on the screen

        mov ah,09h
        lea dx, result
        int 21h

        ;wait for keyboard
        mov ah,1h
        int 21h


        mov ax,4C00h
        int 21h
code ends
end start