[syslinux] Problem: vga TEXT mode has only 8 colors when booting with syslinux

H. Peter Anvin
2014-07-07T18:15:01Z

On 07/01/2014 10:16 AM, Francis Moreau wrote:
> Hello,
>
> First of all, I'm really not an expert so please correct me if I'm
> saying anything wrong.
>
> I noticed a difference when using grub2 or syslinux in my linux virtual
> console (tty[1-5]) which uses VGA text mode (no graphical mode). To be
> sure that I'm using this mode, I did:
>
>     $ dmesg | grep -i vga
>     Console: colour VGA+ 80x25
>
> In my understanding when using the VGA text mode, 16 colours are available.
>
> However, if I try to display those 16 colours after syslinux booting my
> system, I can see only 8 different colours. Here's my syslinux.cfg:
>
>     DEFAULT linux
>     PROMPT 0
>     UI menu.c32
>     MENU TITLE Linux
>
>     LABEL linux
>         MENU LABEL  linux
>         LINUX       ../vmlinuz
>         INITRD      ../initrd.img
>         APPEND      root=PARTUUID=c3b28cc5-93d5-4cdc-b86e-857231520205
> rw quiet
>
> The same application running on the same system displays 16 colours if
> booted with grub2 (but still using VGA text mode). FWIW, grub2's config
> is using:
>
> GRUB_TERMINAL=console
> GRUB_GFXPAYLOAD_LINUX=keep
>
> Could anybody explain me why there's such difference and why syslinux
> leaves the VGA text mode with only 8 colours where there should be 16 ?
>

What system font are you using?

	-hpa