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Booting and gray screen...

Booting and gray screen... Troubleshooting 73 posts Mar 2, 2009 — Jan 27, 2011
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#1 Mon, 2 Mar 2009 - 18:58
Hi,

I'm trying to boot a prototype mac - PowerMac 9700 - and I'm trying both OS X and OS 8/9.

In terms of trying to boot OS 8/9 and the main issue so far is that when I boot using the apple rom (APPL) I only get a gray screen (no happy or sad mac). No cursor or anything else.

In terms of normal macs has anyone seen this behavior before. For example I've seen something similar when SCSI termination was set incorrectly on a PowerMac 8500 with a frozen gray screen but at least this had a cursor on.

Any help would be appreciated.

Thanks,

James.

#2 Mon, 2 Mar 2009 - 19:25
Where did you get a "Power Express" ?

#3 Tue, 3 Mar 2009 - 22:59
Ahh, the infamous Power Express. Very few of these actually boot...if you can get yours to run, you'll have an extremely rare, sought after, collectable machine.

#5 Mon, 9 Mar 2009 - 22:02
Hey,

Thanks for your replies guys.

I got the PEX from a guy who had it originally on the applefritter forums.

I solved the gray screen issue (the mouse/keyboard doesn't work) but it was down to having a CPU installed that the Mac OS ROM didn't recognise (a G4).

Putting a 604e CPU in got Mac OS 8.6 booting.

Full past thread here: http://www.applefritter.com/node/23597

Thanks,

James.

#6 Tue, 10 Mar 2009 - 21:01
I'm very interested to hear the strange boot chime of this Mac.

#7 Fri, 13 Mar 2009 - 17:50
Very cool that you got your Power Express working!!

So are you using the digibarn ROMs, or did you make your own SIMM? Do you have ROM dumps somewhere?

#8 Sun, 15 Mar 2009 - 04:24
Do you have ROM dumps somewhere?
Click to expand...
YES, good question - because we could then pull the startup sound from the appropriate ROM dump so we could hear it!! I've never found a single recording or extraction of this sound on the internet.

Please share the ROM dumps if you have them!

#9 Mon, 16 Mar 2009 - 22:32
Very cool that you got your Power Express working!!
So are you using the digibarn ROMs, or did you make your own SIMM? Do you have ROM dumps somewhere?
Click to expand...
Thanks, I'm using the Digibarn ROM SIMM, which I've borrowed for a while. I've dumped the ROM and will be trying to make my own ROM SIMM.

I've e-mailed 'Denis Nedry' the ROM SIMM dump.

#10 Mon, 16 Mar 2009 - 22:33
Do you have ROM dumps somewhere?
Click to expand...
YES, good question - because we could then pull the startup sound from the appropriate ROM dump so we could hear it!! I've never found a single recording or extraction of this sound on the internet.

Please share the ROM dumps if you have them!
Click to expand...
Hi,

I've now dumped the ROM and can e-mail it, if send me a PM with your e-mail address.

James.

#11 Tue, 17 Mar 2009 - 06:54
This is very cool...now with any luck, the maybe....5 other people who have Power Expresses will be able to get them up and running. People have been trying to get these things to boot for years. Very awesome. :)

#12 Tue, 17 Mar 2009 - 09:36
This is very cool...now with any luck, the maybe....5 other people who have Power Expresses will be able to get them up and running. People have been trying to get these things to boot for years. Very awesome. :)
Click to expand...
Yeah - if anyone knows whose the other people are - please make them aware of the latest developments!

#14 Tue, 17 Mar 2009 - 10:10
I'm also borrowing from Digibarn the SCSI HD which were in their prototype - however they both don't work:

1 x Quantum Viking 3.5 series 455 68pin SCSI-2. Drive spins up but never becomes logically ready

1x Seagate Barracuda ST34371W 68pin SCSI-2. Drive spins up with lots of vibration but then cuts out.

Due to the way they were arranged in the case I suspect that the Quantum Viking would have been the boot disk, and the Seagate the additional HD.

I was thinking of getting a HD specialist (www.xytron.co.uk) to try and resurrect the system HD to see if there were any interesting files on this. I've found a reliable place that would charge £195 ($274.238) if data could be recovered.

Would anyone be prepared to chip in to enable this to happen?

#15 Tue, 17 Mar 2009 - 13:45
I thought I'd heard the unusual second boot sound the PEX makes - it's the same as the one that had been previously uncovered by Applefritter members: http://www.applefritter.com/node/3376

#16 Tue, 17 Mar 2009 - 14:07
BOTH STARTUP SOUNDS are in the digibarn flash dump. The normal one and the one nobody has ever heard.

The original flash dump contains YET DIFFERENT startup sounds. The first one is the 6300 sound on the left channel with someone saying "I know that I rescued this company" on the right. The second one is someone saying "Kill me!" I'm working on figuring out exactly how to interleave these files together so I can then figure out exactly the attributes of the audio, after which I can extract some good samples for everyone to hear!

#17 Tue, 17 Mar 2009 - 14:40
I believe you may not have dumped the Digibarn flash chips properly. It appears that in every single byte, bit 8 is stuck on. i.e. if you did "AND 0x10" to each byte.

Please tell me you haven't sent them back yet!

Note: The original flash chips do appear to be dumped properly, just not the Digibarn ones.

#19 Tue, 17 Mar 2009 - 17:08
I thought I'd heard the unusual second boot sound the PEX makes - it's the same as the one that had been previously uncovered by Applefritter members: http://www.applefritter.com/node/3376
Click to expand...
Aha - I obviously had not read this post.

It appears that I have chosen an incorrect sample rate for the second PEX startup sound from Digibarn. It still would be interesting to extract the original sound directly from ROM if you are able to re-dump it.

Also of interest, it seems the PEX startup sound is cut short. I'm not sure where the rest of the samples are; maybe they just don't exist in this particular ROM. This is a prototype so it seems feasible that they may have cut it short. The only way to know for sure is to listen to the actual PEX starting up and compare to the sound that I extract.

Perhaps the ROM chips are larger than you calculated and you didn't get a complete dump?

#20 Tue, 17 Mar 2009 - 18:30
Here is an AIFF audio extraction from the original flash chips:
http://www.d.umn.edu/~bold0070/temporary/OF_2.0a9.aif

And here is an extraction from the Digibarn chips:

http://www.d.umn.edu/~bold0070/temporary/Digibarn.aif

NOTE that the sound is problematic due to the stuck bit.

I believe that the interleave is configured as 4 bytes from even, 4 bytes from odd, 4 even, 4 odd, etc.
Click to expand...
Hi - Thanks for extracting the sounds. I've re-extracted the Digibarn chips and uploaded with the same file name - so please re-download.

#21 Tue, 17 Mar 2009 - 22:30
I've re-extracted the Digibarn chips and uploaded with the same file name - so please re-download.
Click to expand...
It appears to still have the same stuck bit. The even dump should start with 0x 4800 0008, and it still starts with 0x 5810 1018.

I suppose it must be your dumper, or the way that you've hooked it up to your dumper, seeing as how the flash chips work when installed in the PEX. It could also be a timing problem with your dumper, which could maybe be fixed by reducing the speed.

Something else that might work - maybe you could swap the data bits around? You could put them in reverse order or something. If you re-dump with a different bit stuck (so the currently missing bit gets through on a different bit), I could easily combine the dumps together into one complete, accurate dump. We can verify because the beginning your original ROM and the digibarn flash ROMs are identical.

#22 Tue, 17 Mar 2009 - 23:28
I've re-extracted the Digibarn chips and uploaded with the same file name - so please re-download.
Click to expand...
It appears to still have the same stuck bit. The even dump should start with 0x 4800 0008, and it still starts with 0x 5810 1018.

I suppose it must be your dumper, or the way that you've hooked it up to your dumper, seeing as how the flash chips work when installed in the PEX. It could also be a timing problem with your dumper, which could maybe be fixed by reducing the speed.

Something else that might work - maybe you could swap the data bits around? You could put them in reverse order or something. If you re-dump with a different bit stuck (so the currently missing bit gets through on a different bit), I could easily combine the dumps together into one complete, accurate dump. We can verify because the beginning your original ROM and the digibarn flash ROMs are identical.
Click to expand...
Hi,

I've re-dumped them using a different PLLC32 adaptor and uploaded them to:

http://www.jkalittle.co.uk/jkalittle.co.uk/OF2_3_dump2.zip

Please let me know if these files are fixed.

James.

#23 Wed, 18 Mar 2009 - 00:31
This is also a bad dump. Your data bits seem fine now, but your address bits are screwed up. 1 means working, 0 means "stuck", x means not used:

MSB <---> LSB

xxxx xxxx xxxx 1000 0000 1111 1111 1111

I believe this is the way that the address bits are stuck now (not certain though!):

xxxx xxxx xxxx x010 1000 xxxx xxxx xxxx

Please be very careful; it is possible that your dumper could damage the flash chips if it isn't set up properly. I would recommend researching the pinout of the flash chips and verifying your adapters and dumper configuration.

#24 Wed, 18 Mar 2009 - 00:37
What's the differance between the flash chips and the rom simm?

#25 Wed, 18 Mar 2009 - 00:42
What's the differance between the flash chips and the rom simm?
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This is a strange Mac. It has one part of the ROM stored in flash chips and a different part of the ROM stored in a ROM SIMM. They aren't redundant; both are apparently necessary to boot the Mac. We're not really sure how they work together but we do know that the startup sounds are stored in flash.

#26 Wed, 18 Mar 2009 - 00:43
ahhh... So the 3 meg one is rom, and the two 512k ones are flash?

#27 Wed, 18 Mar 2009 - 00:46
Oh, and the "even" and "odd" parts are the same as the "hi" and "lo" parts I've seen on some other roms??

#28 Wed, 18 Mar 2009 - 00:49
Do you think it would be possible to install the Flash chips back into the PEX, boot into Mac OS 9, and use a software ROM dumper run right on the Mac? I'm not sure exactly how this would work with 2 separate ROMs like this, but it might be a safer approach. It could potentially work. I can de-interleave the dump back into two 512k dumps that you could then burn to new flash chips if this works.

It's also possible that you'll only get the ROM SIMM to dump this way. There's no telling.

#29 Wed, 18 Mar 2009 - 00:50
If someone can get a PM9700 running, it'd be neat to write an emulator for it :p

#30 Wed, 18 Mar 2009 - 00:57
ahhh... So the 3 meg one is rom, and the two 512k ones are flash?
Click to expand...
They're both ROM. The 3MB one is the ROM SIMM, and the 1MB (2*512k) is flash.

Oh, and the "even" and "odd" parts are the same as the "hi" and "lo" parts I've seen on some other roms??
Click to expand...
Could be. The Flash ROM is stored in two separate flash chips, and it is easier in some situations to interleave the data between the 2 chips. With this one, 4 bytes come from "lo", then the next 4 are from "hi", next 4 from "lo", etc. Back and forth like that. It's not always 4 though. I have written a small program for this that de-interleaves the two files back together into one big file so I could pull the sound samples earlier in this thread.

If someone can get a PM9700 running, it'd be neat to write an emulator for it :p
Click to expand...
Once we get a proper dump of this ROM, you may be able to use it in SheepShaver. That would technically be an emulation of a 9700.

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