Wow

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

    mov ah, 00h
    mov al, 01h
    int 10h

    mov si, text_string ; Put string position into SI
    call print_string   ; Call our string-printing routine

.mainLoop:
    mov ah, 00h
    int 16h
    mov ah, 0Eh
    int 10h
    jmp .mainLoop

text_string:
    db 020h, 0DBh, 0DBh, 0DBh, 020h, 020h, 020h, 0DBh, 0DBh, 0DBh, 020h, 00Ah, 00Dh
    db 0DBh, 020h, 020h, 020h, 0DBh, 020h, 0DBh, 020h, 020h, 020h, 0DBh, 00Ah, 00Dh
    db 0DBh, 020h, 020h, 020h, 0DBh, 020h, 0DBh, 020h, 020h, 020h, 020h, 00Ah, 00Dh
    db 0DBh, 020h, 020h, 020h, 0DBh, 020h, 020h, 0DBh, 0DBh, 0DBh, 020h, 00Ah, 00Dh
    db 0DBh, 020h, 020h, 020h, 0DBh, 020h, 020h, 020h, 020h, 020h, 0DBh, 00Ah, 00Dh
    db 0DBh, 020h, 020h, 020h, 0DBh, 020h, 0DBh, 020h, 020h, 020h, 0DBh, 00Ah, 00Dh
    db 020h, 0DBh, 0DBh, 0DBh, 020h, 020h, 020h, 0DBh, 0DBh, 0DBh, 020h, 00Ah, 00Dh
    db "Press ENTER to start. (Well, not yet.)", 00Ah, 00Dh, 0


print_string:           ; Routine: output string in SI to screen
    mov ah, 0Eh     ; int 10h 'print char' function

.repeat:
    lodsb           ; Get character from string
    cmp al, 0
    je .done        ; If char is zero, end of string
    int 10h         ; Otherwise, print it
    jmp .repeat

.done:
    ret

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