section .data
     msg db 'The sum is:',10
     msgLen equ $-msg
     num1 db 30H
     num2 db 15H

section .bss
      sum resb 1
      temp resb 1

section .text
    global _start

_start:
    mov rax, 1
    mov rdi, 1
    mov rsi, msg
    mov rdx, msgLen
    syscall
    mov al,byte[num1]
    add al,byte[num2]
    mov  byte[sum],al
    mov bp,2
    up:rol al,4
       mov bl,al
       and al,0Fh
       cmp al,09
        jbe down 
        add al,07h
        down:Add al, 30h
        mov byte[temp],al
        mov rax, 1
        mov rdi, 1
        mov rsi, temp
        mov rdx, 1
        syscall 
        mov al,bl ; AL = 7AH = 07A,0AH
        dec bp
        jnz up
        mov rax, 60
        mov rdi, 0
        syscall