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Booting and gray screen...

Outlander

Well-known member
Oh man this machine I had forgotten about.

I have an ES 275mhz G3 card sitting around somewhere that I got off of eBay a while back. All it said was G3 275mhz on the side but the stupid card wouldn't work in my 9600. I'll have to find that card now and see if it's anything special or just a dud G3 card.

 

Bunsen

Admin-Witchfinder-General
That woulkd make sense for a development prototype. Presumably the flash was used for the part of the ROM which was not considered finalized.

 

Dennis Nedry

Well-known member
Do you want the startup sounds, ROM dumps or both? I don't have them handy at the moment but I will next monday.

 

jimjamyahauk

Well-known member
Hi 'Dennis Nedry',

Hope you're well.

I was wondering if you could post/e-mail me the de-interleaved rom file for the Power Express 9700 as the old link isn't working at the moment.

Many thanks,

James.

 

balrog

Member
None of these dumps seem have valid checksums. Could they possibly be redumped?

When dumping, always take multiple dumps and verify that they match. If you've done this and they do match, then something weird is going on.

Thanks!

 

Dennis Nedry

Well-known member
None of these dumps seem have valid checksums.
Where are you getting the correct checksum with which to compare? Are you using the first group of bytes of the file or something? I do not believe that the first bytes of the flash dump are a checksum because a startup sound is located there.

If you haven't already, have a look here for Mac ROM checksum verification:

http://www.d.umn.edu/~bold0070/projects/checksum/

Being that this is from a prototype, they may not have bothered with checksumming, or it may be done a different way.

 

Dennis Nedry

Well-known member
Also, the ROM SIMM dump was done with a software dumper running on an actual PEX Mac, so it's highly unlikely for it to have an error.

 

balrog

Member
The structure of this ROM is as follows:

3 MB on ROM SIMM

1 MB on flash chips

The ROM SIMM is not supposed to change, but the Flash chip can and did during development. This was the reason for only 3MB being checksummed: the last 1MB, which resided on the Flash chips, could easily be changed.

Therefore, the fact that only 3MB was checksummed was NOT a bug, and was completely deliberate!

What utility was used to dump? We usually recommend CopyROM from http://www.emulators.com/freefile/MACUTILS.ZIP because many other dumpers only grab the first 3MB or otherwise scramble the dump. Would it be possible for a re-dump to be taken with this version of CopyROM, as well as a screenshot of the CopyROM window? This would establish whether the ROMs actually are weird, or that the dump was bad.

Thank you!

 

jimjamyahauk

Well-known member
Hi,

I've done a comprehensive dump of the ROM SIMM using 3 different utiltiies and 3 times per utility. I tried copy rom, but this didn't launch properly. I've also included a report from TattleTech about the ROM SIMM and the Apple System Profiler report.

Interestingly, the Tattletech report shows the full rom as being just over 3MB - i.e. the 1MB on the flash chips doesn't show up at all to the OS.

In this zip file are further zip files for each set of ROM SIMM dumps, which contains the program used and the dumps themselves. Dumps from the Flash chips are also included (which were done via a USB chip programmer)

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

James.

 
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