Mini Boot Loader OS

+----------------------------------------------+
| Compile nasm -f bin -o loader.bin loader.asm |
| For write use DEBUG:                         |
| -n loader.bin                                |
| -l 0                                         |
| -w 0001                                      |
| -q                                           |
+----------------------------------------------+
section .text
bits 16
org 0x7C00

main:
xor ax,ax
mov ds,ax

mov si,txt
call prnstr
jmp $

prnstr:
mov ah,0x0E
mov bh,0x00
mov bl,0x07

.nextchar:
lodsb
cmp al,0x0
jz .return

int 0x10
jmp .nextchar

.return:
ret

section .data
txt db 'Mini Boot Loader OS >>',13,10,0
times 510-($-$$) db 0
dw 0xAA55