; NASM x86 Floppy Bootblock "Hello, world!"
; written 2007-03-17 by Dirk Jagdmann <doj@cubic.org>
; https://www.cubic.org/source/bootblock.asm
;
; to assemble this do something like:
;   nasm -f bin -o bootblock.bin bootblock.asm
; then write it to a floppy (on UN*X style systems):
;   dd if=bootblock.bin of=/dev/fd0
; or create a floppy image to use in VMware or similar:
;   dd if=/dev/zero of=bootblock.img bs=1024 count=1440
;   dd if=bootblock.bin of=bootblock.img conv=notrunc

	org 0h
start:
	; reset VGA
	mov ax, 0003h
	int 10h

	; write string
	mov ax, 7C0H    ; segment setup
	mov es, ax
	mov bp, msg	; msg pointer
	mov ax, 1300h  	; ah=function, al=write mode
	mov bx, 000Fh  	; bh=page, bl=attribute
	mov cx, 13	; number of chars
	mov dx, 0C23h	; dh=row, dl=column
	int 10h

	; wait for key
	xor ax, ax
	int 16h

	; reset
	int 19h
        jmp 0xF000:0xFFF0

msg:	db "Hello, world!"