Why isn't the text colored when using the 0Eh 10h interrupt?

Question

I\'m using the 10h interrupt with AH as 0Eh to output \"Hello World!\" The text is ouputted but its not colored. I\'m running it on qemu-system-x86_64, assembling with NASM,

Answer 1

I was able to print with color by using the 09 for the 10h interrupt, instead of 0E. You do, however, have to change the cursor position after each character to use this method. Here is the working code.

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

    jmp $                   ; Jump here - infinite loop!


    text_string db 'Hello World!', 0


print_string:                   ; Routine: output string in SI to screen


 .repeat:
    mov ah, 09h             ; int 10h 'print char' function
    mov bh, 0x00
    mov bl, 0x03
    mov cx, 01h
    lodsb                   ; Get character from string
    cmp al, 0
    je .done                ; If char is zero, end of string
    int 10h                 ; Otherwise, print it
    mov bh, 00h
    mov ah, 03h
    int 10h
    mov ah, 02h
    mov bh, 00h
    inc dl
    int 10h
    jmp .repeat

 .done:
    ret


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