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Re: hosed nvram on OldWorld Mac

Dang, this arrived with perfect timing!  Get it, timing?  See my [lengthy] next post for details.  I'm still composing it.


Michel Lanners wrote:
> On   3 Feb, this message from Andrew Sharp echoed through cyberspace:
> > No, I'm getting no output on the monitor.
> Important side-note: control video hardware as initialized by OF is
> notoriously bad at doing monitor timings. By default (i.e. after a PRAM
> reset) it sets up some weird mode that resembles 640x480@60HZ, but
> isn't.
> Depending on your monitor, it may or may not sync to this sh... My old
> Phlips 17B does, my newer Dell P990 doesn't.
> If that is your problem, get yourself a serial console, reset PRAM, and
> boot with cmd-opt-O-F into OF, set your terminal to 38400 and conectit
> with a null-modem cable to the modem port. You should have the OF user
> interface there.
> >From there, do like this (from a mail from some time ago...):
> ______________________________
> Fixes for Apple OpenFirmware 1.0.5
> Alan Mimms (alanm@unforgettable.com)
> Sun, 17 Aug 1997 19:08:19 +0000
> Hi.
> I have finally had enough with the buggy screen and disk drivers in Apple's
> Open Firmware on PowerMac 7200, 7500, 7600, 8500, 9500, and probably some
> others I'm forgetting.  So I have written some NVRAMRC based patches to
> Open Firmware to hack around the bugs enough for my purposes anyway.  I
> hope the hacks may help you too.
> Start up and break into your Open Firmware -- Cmd-Opt-O-F during the boot
> beep held down until the "user interface" for Open Firmware comes up on
> your screen or, if you're smart, your serial port.  The banner printed by
> Open Firmware shows the Open Firmware version.  These patches ONLY apply to
> Open Firmware version 1.0.5.  Other versions will crash if these patches
> can be applied at all!
> Type at the prompt:
>     nvedit
> and hit control-L to see the cryptic stuff that is part of your Open
> Firmware's startup sequence.  This stuff patches various bugs in the ROM.
> Hit control-N enough times that you no longer see a new line of
> gobbledegook every time several times in a row.  This means you're at the
> bottom.  Either paste the following into a terminal session (NOTE: must be
> at least a dozen or so ms delay between characters and maybe 100ms between
> lines to work right!) or else enter the following lines very very carefully:
>         dev /bandit/gc/via-cuda
>         ' write value &W
>         : -&We &W swap - execute ;
>         : P1 4D8 -&We false 548 -&We ;
>         &W FC + ' P1 BLpatch
>         : P2 0C 2 ms ;
>         &W E0 + ' P2 BLpatch device-end
>         : wBoot
>         begin
>          boot-device ['] $boot catch drop
>          ." -Waiting for boot-device" cr
>          d# 500 ms
>         key? until
>         ;
> Note that ALL whitespace above except for the line indentation is REQUIRED.
> FORTH is a very very very strange "language".  It may be safe to leave the
> line indentation as I have it above when pasting if you wish.  It's
> wasteful but who cares?
> At the end of this laborious typing (or pasting) session hit control-C (yes
> that's right: control-C is the end of editing session character in Open
> Firmware).  Then type at the prompt
>         nvstore
> to save the changed NVRAMRC variable into NVRAM.
> The first block fixes a bug in the via-cuda driver in which not enough time
> is given for the device to settle when it is told to set the video
> controller's clocks up.
> The second block defines a FORTH word that can be used in place of the
> normal boot-command contents to wait for the disk to spin up before
> attempting to really boot.  This avoids the standard "black screen the
> first time you power on the computer each day" problem.
> Then type at the prompt
>         setenv boot-command wBoot
> This sets up the default command executed on auto-boot (normally on power
> on) to run the above disk spinup waiting hack.
> FYI: the reason I know about this stuff is that I worked for about two
> years as the Copland booting guy.  Sheesh...
> Please don't inundate me with a bazillion questions about Open Firmware.  I
> have a real job and it takes 60+ hours a week of my time.  I get PAID to do
> it.  I just did this to fix MY PPC Linux box and I wanted to help you folks
> out a teeny bit if I could.  No, I don't work at Apple anymore.  Cancelling
> Copland was the last straw.  I worked there more than nine years.  (sigh)
> Happy trails.
> a
> A copy of the universe is not what is required of art; one of the damned
> things is ample.   -- Rebecca West, The Creators, by Daniel J. Boorstin
> ___________________________________________
> Hope this helps
> Michel
> -------------------------------------------------------------------------
> Michel Lanners                 |  " Read Philosophy.  Study Art.
> 23, Rue Paul Henkes            |    Ask Questions.  Make Mistakes.
> L-1710 Luxembourg              |
> email   mlan@cpu.lu            |
> http://www.cpu.lu/~mlan        |                     Learn Always. "

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