How to print Spanish characters on VGA text mode framebuffer?

Question

I am writing my operating system - english-spanish translator for x86 architecture. I write the OS kernel in C language (and use gcc compiller), I do not have a standard C library. And I can't figure out how to output Spanish characters that are not in English. I usually output strings like this:

void out_str(int color, const char *ptr, unsigned int strnum, int pos)
{
    unsigned char *video_buf = (unsigned char *)VIDEO_BUF_PTR;

    video_buf += 80 * 2 * strnum + pos * 2;

    while (*ptr)
    {
        video_buf[0] = (unsigned char)*ptr; // #define VIDEO_BUF_PTR (0xb8000)
        video_buf[1] = color;               // 

        video_buf += 2;
        ptr++;
    }
}

Thank you in advance for your help!