Boot hello world

08 Mar 2011

; Tell the compiler that this is the 0 address
[ORG 0] 
    jmp 07C0h:start   ; Jump to start

    msg db "Hello boot world ", 2, 0 ; My string
         ; the 2 byte should provide some fun

start: 

    ; Setting up the segment registers
    
    mov ax, cs
    mov ds, ax
    mov es, ax
    
    
    ; Writing the string 

    mov si, msg
print:    lodsb
    cmp al, 0
    je hang
    mov ah, 0Eh
    mov bx, 7
    int 010h    ; BIOS video service interrupt
    
    jmp print
    

hang:     
    jmp hang


    times 510-($-$$) db 0
    dw 0AA55h

.

I saw this here, so is not my merit..

to run:
copy this to a .asm file, e.g. b.asm, then assemble it with
$ nasm -o b.bin b.asm
and finaly write it to some pendrive with
dd if=b.bin of=/dev/YOURPENDRIVE
e.g $ dd if=b.bin of=/dev/sdc
Boot the pendrive and you should get a funny message on screen =)
if you have qemu installed you can boot directly the binary
$ qemu -hda b.bin