bits 16				; mode 16bits
org 0x7C00			; mbr ae loaded at 0x7C00
mov al, 41h         ; put 'A' in al
mov ah, 0eh         ; we want to call function 09h (Write Character and Attribute at Cursor) from interupt 10h
int 10h
times 510 - ($ - $$) db 0	; fill up to 510 with 0
dw 0xAA55			; MBR magic number