Passing vga=normal causes DSL X Setup to run

Forum: X and Fluxbox
Topic: Passing vga=normal causes DSL X Setup to run
started by: edochan

Posted by edochan on May 23 2006,02:19

I'm making a remastered version of Damn Small Linux 2.3, and I'm trying to get rid of the "You passed an undefined mode number" line that often pops up during boot and freaks out non-technical users.

When I've done Knoppix remasterings in the past, I've been able to get rid of it my changing the boot parameter "vga=791" to "vga=normal". This allows my users to boot straight into graphical mode without being asked any confusing questions about X. However, when I do this with DSL, it causes the DSL X Setup dialog to appear. (This happens whether I change "791" to "normal" in the isolinux.cfg file or enter "dsl vga=normal" it manually at the boot prompt.) The same thing seems to happen on whichever of several different computers I test on.

So I'm wondering:
a) Why is this happening on DSL when it doesn't happen on Knoppix?
b) Is there a way to stop the DSL X Setup dialog popping up?
c) Alternatively, is there any other way to avoid the "undefined mode number" message?

Posted by roberts on May 23 2006,04:16

Knoppix's target is not to support low end hardware as much DSL does.
vga=791 by looking at the vga code table, f3, at first boot prompt show a 1024x768 display. Many low end machines can boot vga=normal and not able to display 1024x768. I test run DSL on a 640x480 display. In fact I would venture to say most machines that need vga=normal will most likely need 800x600 display. I once made the system boot vga=normal and then into an 800x600 display with the resolution picked started but it was not adopted. But since you are remastering you can hack it anyway you like.

Posted by edochan on May 23 2006,08:21

Hi Roberts.

Thanks for your reply.

Any idea which file(s) I should hack to get my DSL remaster to do vga=normal without going through the DSL X Setup?

(I thought I'd find something in /etc/init.d/knoppix-autoconfigure, but I couldn't see anything relevant.)

Posted by pr0f3550r on May 23 2006,10:37

My two cents:
vga=normal is supposed to be for legacy hardware with very bad graphic cards (kinda pre 1988). If I boot with with vga=normal in qemu the only colors available are blue and green.

vga=normal should be avoided in a remaster. Pick a standard resolution (800x600) and that's it.

Posted by edochan on May 23 2006,11:00

Interesting suggestion, pr0f3550r.

I just tried booting with things like "dsl vga=789" (600x800 24-bit) and "dsl vga=788" (600x800 16-bit), but I still get the "undefined mode number" error message - _and_ the DSL X setup screens.

My aim here is to get rid of any English/Techlish messages that are going to confuse my (Japanese) users and stand between them and what they want to do (use my software).

Apart from invoking "vga=normal", do you know of any other way to get rid of the "undefined mode number" error?

Posted by doobit on May 23 2006,12:49

I always type dsl vga=795 noapm, because my graphic card supports it, and it's the native resolution of my LCD monitor. It works. However that sets the properties for the bootup resolution. You need to set the resolution for X with xsetup.sh.The undefined mode number does not show up after that if you backup. Once you have backed up your settings for X you will no longer be prompted for the settings. The remaster should include the configuration script (I think it's xauthority.sh or something like that, but it's automatically written into the backup.tar.gz file anyway), or you can give each student a pendrive to save their settings on, or with a copy of your preconfigured backup file on it.

Posted by edochan on May 23 2006,13:41

OK, I think I've figured out what I need to do here.

Apparently xsetup.sh always gets called (by startx), but only displays the dialog if you've asked for something other than vga=791. (Or if, as doobit says, there's already a default saved to the disk or pendrive.) Vga=791 is actually hard-coded into xsetup.sh.

So I can run the thing with vga=normal (to avoid the "undefined mode number" error), and hack xsetup.sh a little bit to run with sensible defaults, without bothering my users with a dialog.

Thanks for your comments,

Ed