BITS 16
start:
    mov ax, 07C0h       ; Set up 4K stack space after this bootloader
    add ax, 288     ; (4096 + 512) / 16 bytes per paragraph
    mov ss, ax
    mov sp, 4096

    mov ax, 07C0h       ; Set data segment to where we're loaded
    mov ds, ax

loop:
    mov ah, 00h

    int 16h

    mov ah, 0Eh

    int 10h

    cmp al, 0Dh
    je set_video_mode

    jmp loop

set_video_mode:
    mov ah, 0Fh
    int 10h
    cmp al, 13h
    je set_video_mode_back

    mov ah, 00h
    mov al, 13h

    int 10h

    jmp init_draw

set_video_mode_back:
    mov ah, 00h
    mov al, 3h

    int 10h

    mov al, 0

    jmp loop

init_draw:
    mov ax, 0A000h;
    mov es, ax;

    mov ax, 32010
    mov di, ax
    mov dl, 7

    mov [es:di], dl

    jmp draw

draw:

    inc di
    inc dl

    cmp di, 32009
    je loop

    cmp dl, 13
    je c_color

    mov [es:di], dl

    jmp draw

c_color:
    mov dl, 0
    jmp draw

    times 510-($-$$) db 0   ; Pad remainder of boot sector with 0s
    dw 0xAA55       ; The standard PC boot signature