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Re: apt-cdrom-install not found (?)

Hello everyone

Many thanks for all of your help. It worked...BUT! I don't know what did the trick, so I will just say a few things here.

(Risto, thanks a lot, I did use some of these parameters in the end)

1) So, we established that the monitor is "sensitive" and it will not play very nicely with the driver. Therefore, we need to do manual setup.

2) Manual setup means that we have to define at least 2 things:
a) Modeline statements so that X knows how to drive the monitor circuitry (actual frequencies for blanking, refresh, etc)
b) Monitor modes, including the preferred mode

3) These are all specified within the xorg.conf. The default installation of Debian will not create one of those because (i guess) more recent equipment is better behaved and the X server will auto-detect and use devices during every startup. To create a very simple xorg.conf one has to do something like:
>> X -configure
which will create a xorg.conf within the home directory of the user who run the command....

At this point I have to say that in my case, most of this work was performed with linux running in single user mode because I had no other way of stopping the X Server from launching automatically (which meant a black screen and unusable computer). Therefore, my default xorg.conf ended up in /root. Its default position is in /etc/X11 so:
>>cp /root/xorg.conf.new /etc/X11/xorg.conf

4) So, now we have a xorg.conf. This is divided into (mostly) self-explanatory Sections. Essentially:
a) We need to specify a set of "ModeLine"s in the section "Monitor" one for each resolution and refresh rate.
b) We need to specify a VertRefresh and HorizSync in the section "Monitor" to drive the monitor properly
c) We need to pass some additional parameters (optionally) to the section "Device"
d) We need to specify which resolutions are to be matched with each color depth in the section "Screen"

4.a) Specifying "ModeLine"s: I hate it when I have to punch numbers at random wishing that "it will be OK, we copy this off of some forum and it works". So,  it turns out that X has a utility called CVT which looks at various clock signals reported by the system and returns the timing coefficients required for ModeLine. It's like this:
>> cvt 640 480 60 #So, 640x480 at 60Hz refresh rate
And you get back a ModeLine.

In my case, still in single user mode, I generated 3 "ModeLine"s for 640x480, 800x600 and 1024x768.

If you want one of these resolutions to become your "preffered" one, you might want to specify:

Option "PrefferedMode" "800x600"

The "800x600" is the identifier for the ModeLine....It doesn't mean a thing, it could have been "Blahblah_moreBlah".

4.b) Specifying "VertRefresh" and "HorizSync": This is perhaps the most important thing in this case. There are a lot of xorg.confs out there and the answer to what one sets for these two parameters changes from author to author even when they are supposedly referring to the same machines.
The ones that really seem to work are:

HorizSync 60-60 #(http://en.wikipedia.org/wiki/Horizontal_scan_rate)
VertRefresh 75-117 #(http://en.wikipedia.org/wiki/Refresh_rate)

4.c) The additional parameters that I felt should be sent to the r128 driver were:
Option "DISPLAY" "CRT"
Option "UseFBDev" "True"
Option "NoAccel" "True"

Why just these? Because --> http://www.x.org/archive/X11R7.6/doc/man/man4/r128.4.xhtml

4.d) Specifying resolutions and color depths:
Color depth is the number of bits reserved to represent a colour (http://en.wikipedia.org/wiki/Color_depth). So, at a colour depth of 8 we can represent 256 colours because 256 = 2^8.

At section "Screen" we can specify which graphics card and monitor are to be associated with a number of different modes.

A display mode" specifies the resolution (how fine is the canvas that composes the image) and the colour depth. X, be default creates entries under "Screen" for colour depths of 1 (b&w), 4, 8, 15, 16, 24 but does not necessarily populate them. To specify Screen Modes we have to add the "ModeLine" identifiers we wish under each colour depth display mode. While we are at these section we can also specify a preffered colour depth with:

DefaultDepth 24

My primary problem however turned out to be that all of my tests of these configurations were performed at Single User mode with:

>> X -config /etc/xorg.conf

I never managed to get the X server working, instead, the driver would report (via /var/log/Xorg.log) that it tried a very large number of different display modes and that because all of these failed it now reverts to a specific **_"ModeLine"_** which was 1024x768 at 75 Hz of a refresh rate (So, knowing what a ModeLine is and how it looks like , pays off when you have to read the log files). T

he monitor does not support this mode and it therefore was going blank, at which point I was going back to the console, killing the server and doing some more reading.

My last resort, was to disable the automatic launching of X and restart the system in multi-user mode where I would also get internet access more easily and I could at least update it from console and look further.

I did:

>> update-rc.d -f gdm remove

(Because --> http://www.debian-administration.org/article/28/Making_scripts_run_at_boot_time_with_Debian)

And I was expecting that upon reboot the system would ask me to login via the text console...BUT! I was wrong.

Instead of this, the system booted INTO GRAPHICS mode!

Severly limited software graphics mode....but at least, the system is usable at this point and it can access the internet.

So, all in all, I think that the key settings here are the HorizSync and VertRefresh that have to be set properly in the conf file for the monitor to come alive. But being aware of the rest of the settings definitely helps too.

Thank you all for your time, I hope this was a bit helpful from my part as well.

All the best

On Sat, Nov 1, 2014 at 6:36 PM, Risto Suominen <risto.suominen@gmail.com> wrote:
2014-11-01 17:55 UTC+02.00, Athanasios Anastasiou <athanastasiou@gmail.com>:
> If anyone has a working slotloader G3 @400MHz can you please post your
> "device" section?
Driver "ati"
Option "UseFBDev" "false"
Option "SWCursor" "true"
Option "ForcePCIMode" "true"
Option "XAANoOffscreenPixmaps" "true"
Option "DRI" "true"
Option "NoInt10" "true"

The exact distribution is MintPPC 11, which is based on Debian
Wheezy/Sid (actually installed using a Debian CD).


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