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@kunst1080
Last active September 3, 2016 07:26
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Hello world
; boot.asm
; setup segment register
mov ax, 0x07c0
mov ds, ax
; setup display
mov ah, 0x0 ;setup video mode
mov al, 0x3 ;0x3 = text mode, color, 80x25
int 0x10 ;0x10 = video service
mov si, msg ;target of lodsb
mov ah, 0x0E ;0x0E = tty
print_character_loop:
lodsb
or al, al
jz hang ;jump if zero
int 0x10 ;when ah is 0x0E, then print
jmp print_character_loop
msg:
db 'Hello World!', 13, 10, 0 ;13 = \r, 10 = \n, 0 = NULL
hang:
jmp hang
times 510-($-$$) db 0
; this is a comment
db 0x55
db 0xAA
boot.bin: boot.asm
nasm -f bin boot.asm -o boot.bin
qemu: boot.bin
qemu-system-x86_64 -curses boot.bin
clean:
rm *.bin
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