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Re: XFBdev resolution platinum 7200/90



On  12 Sep, this message from cesagbo@b2b2c.ca echoed through cyberspace:
> Quoting Michel Lanners <mlan@cpu.lu>:
>> >       In this condition X use 800x600 résolution.  I understand that
>> the 800 x600 mode need to be initialised before, or else it goes
>> 640x480.  How can i pré-initialize the monitor mode so i can start X
>> directly.  When i use: fbset 800x600-60 the framebuffer comply but X
>> doesn`t care unless i use the "trick".
>> 
>> Hmm, have you tried 'fbset -a <mode>' like I suggested? Do you have a
>> Mac<->VGA adapter? Old Macs don't do DDC (like modern i386 grafic
>> cards), but rather have three pins on the DB15 Mac monitor connector,
>> and the monitor indicates its type (and hence its capabilities) by
>> some
>> 
>   What the -a switch mean in fbset -a <mode>.  It doesn`t appear in the manual.

-a forces fbset to change all virtual consoles at once.

>   What is DDC?

'Display Data Channel'. It's the way by which a computer can query the
monitor's capabilities.

>   Why do the monitor isn`t probed when i used the trick with fbzen and <ctrl-c>?

On old Macs (older than very recent; nothing to do with
oldworld/newwolrd), there is no other way to probe the monitor than look
at the sense value reported by the monitor's connector (which is a
static code).

It seems your monitor, probably through a misconfigured VGA <-> Mac
adaptor, identifies itself as a fixed 14" monitor, doing only 640x480.

>   I tought that an old world ppc could not use a new world kernel!

There is no difference kernel-wise. What changed is the way _MacOS_ is
booted. Here is the short version of the story: on an oldworld,
OpenFirmware (equivalent to the BIOS on i386) boots code in a ROM chip,
which is essentially the core of MacOS. On a newworld, there's no MacOS
ROM chip anymore; that part is located in a file on disk which is loaded
by OpenFirmware.

On newworlds, therefore, Linux has it much easier to boot, since
OpenFirmware can indeed load a file from disk and execute it. That's not
as easy on oldworlds...

Cheers

Michel

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Michel Lanners                 |  " Read Philosophy.  Study Art.
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