Performa 6200 Cache/ROM DIMM Error

[Hoagie]

Hi!

So I've already had a thread about my Performa 6200 not booting at all. After I got the PSU repaired I have a new problem now regarding the Cache/ROM DIMM.

The performa is booting up and gives a (German) error message about a hardware problem and calling customer support regarding replacement of the Cache/ROM DIMM.

As mentioned I have had someone repair the PSU and because I had to ship it there and he offered me the service, I have had him recap the logicboard as well. Because it seems that the internal CD-ROM is also not working (at least it's not booting of my burned 7.6 CD), I installed a new system 7.6 using SheepShaver and an "mac_oldworld_rom4mb.rom". I then wrote the image file onto a CF-card which I installed via an CF2IDE-Adapter.

It has it's original RAM-Module and an additional. I already tried booting the system with only either one of them installed, but the error remains.

It took me some time to get a replacement Cache/ROM-dimm, however, I am receiving the same error message.

So what I don't know:

Is the logicboard damaged or was it maybe damaged during the recapping?
Are both my Cache/ROM-dimms faulty?
Is my OS installation faulty? In SheepShave it's working just fine and I used the same procedure with Basilisk II for my Macintosh SE and OS 7.1 and it's working just fine.

Too bad, I don't have a running system to swap components for testing...

Appreciate any help / ideas about what to do next...

Thank you-

 

[dtaylor]

I'm trying to remember if the 6200 could boot from a floppy, and unfortunately my retro Mac stuff, including 6300, isn't setup right now. But I want to say that those models could floppy boot. I would try that to see if there's a problem with the CF card (Mac OS install, card itself, or adapter). I would also want to try a different RAM SIMM to rule out the possibility of both sticks being bad.

That said, you are getting a very specific error message. I wonder if perhaps your replacement Cache/ROM DIMM is also bad. I'm not sure how much time or money you want to put into it as Performa 6200/6300 units aren't that hard to find on eBay. If you just want to try and save the machine, getting access to a 2nd working unit would let you test ROM, RAM, and the CF setup to determine if the motherboard is what's damaged.

 

[pizzigri]

Where are you located? I may have a cache/ROM simm for the 6200 lying around.

 

[pizzigri]

Where are you located? I may have a cache/ROM simm for the 6200 lying around.

Turns out I do…

 

[Hoagie]

I'm trying to remember if the 6200 could boot from a floppy, and unfortunately my retro Mac stuff, including 6300, isn't setup right now. But I want to say that those models could floppy boot. I would try that to see if there's a problem with the CF card (Mac OS install, card itself, or adapter). I would also want to try a different RAM SIMM to rule out the possibility of both sticks being bad.

I am absolutely not familiar with those kind of MACs (I am just very curious about them...) - so coming from the PC world it doesn't look like a RAM error to me - but then...what do I know. I believe it will boot from floppies. However, installing System 7.5 from floppies will take so many floppy disks that I am looking for other ways (unless I am sure it's the installation). I just ordered another BlueSCSI for an old powerbook (I also have one in my Mac SE) that I could use as a CD-ROM substitute. But yet I can't really believe it's the software. As far as I understood how Macintosh OS's work, you can pretty much swap them around in compatible Systems and they will just run.

That said, you are getting a very specific error message. I wonder if perhaps your replacement Cache/ROM DIMM is also bad. I'm not sure how much time or money you want to put into it as Performa 6200/6300 units aren't that hard to find on eBay. If you just want to try and save the machine, getting access to a 2nd working unit would let you test ROM, RAM, and the CF setup to determine if the motherboard is what's damaged.

Here in Europe, especially in Germany they are a more rare find. I missed to get another one and I am not really willing to pay a fortune for another one in "unknown condition". Having a running unit would really make trouble shooting much more easier...

Regarding the cache/ROM DIMM the repair manual even says to replace it, once you experience problems and it's a certain series. But I just don't know if it's worth trying another one...

Where are you located? I may have a cache/ROM simm for the 6200 lying around.

Germany. Do you know, if it is working? I don't need a third one that's broken - or a third one that's working and still not knowing where the error is...

I believe, the first step I will do is installing it in sheepshaver using the recovery cd I've found on archive.org and giving writing this CF card once more...

Thank you guys!

 

[pizzigri]

Hoagie, I’m in Italy, so shipping should not break bank. And I don’t know how expensive you're thinking, but I would part from it for 10 euro… however … 6200 boards should not be more expensive than 50 euro plus s&h. I sold my last one a few months back unfortunately - and rather than spending on parts, I’d get a working board tbh

 

[Hoagie]

So if you know your ROM is working, I would give it another try. Unfortunately I spent some money for getting my board recapped and all the 50 € boards I see online are „function unknown“ and I just don’t want to have more broken stuff here

 

[Cory5412]

The 6200 (and all other Macs which share the same base architecture, of which there are many) can boot from CD/floppy, as well as other random external SCSI devices.

However, based on:

The performa is booting up and gives a (German) error message about a hardware problem and calling customer support regarding replacement of the Cache/ROM DIMM.

I think you are legitimately having a cache/ROM problem.

Unfortunately, this problem was somewhat common on this model and some based on it, there was a recall and a replacement program and everything.

It seems like the original owner of yours didn't do the program when it was current, so unless there's a modern rom replacement for this machine (similar to the rominator) then getting a rom out of a parts unit or buying a known-good rom for someone is likely the only solution.


I'd say keep at it - the 6200 (at least on the English-language scene) is often maligned as one of the worst Macs ever, but if you sit down and benchmark it, it does nearly identically (and in some sub-tests, better) to the 6100. They're some of the slowest extant PPC Macs, but with 7.6.1/8.1 and some software mods they're fast enough for most tourism and running a lot of consumer/edutainment software. They'll run pro/technical software as well, just not as fast as a pro machine.

The 6200, I think, is a genuinely under-appreciated machine and aside from running into this should be a good intro to the platform/hobby!

Sorry the machine is giving you so much trouble, but hopefully you're in the home stretch now!

 

[pizzigri]

Cory, is there a way to know if a ROM is a replacement? Like some part number or so? I can post detailed images of both sides.

 

[Hoagie]

I think you are legitimately having a cache/ROM problem.

I kinda hope so...however it's the second ROM now and it won't work - it's the exact same version as the previous one, though. So there is a chance both ROMs are damaged. However, the repair manual is talking about errors like system freezes and such, and with mine I believe the Cache doesn't work properly and that's the reason the system will boot up but won't start system extensions or bigger programs. It could still be a damaged bus line on the logicboard. But I am willing to give it a try to a third rom.

Do you know if it has to be the exact 6200 ROM or would a ROM out of different machine (like 6300) work as well...?

Cory, is there a way to know if a ROM is a replacement? Like some part number or so? I can post detailed images of both sides.

I don't know if I may post screenshots of the repair manual for copyright reasons. However, if you find the "Performa 6200/6300 Series" Service Manual, on pages 47f you find a description of the ROM-Version which has to be changed. In other words, if your ROM doesn't look like this, you got the new version.

 

[Cory5412]

I don't off hand know the part numbers or any signifying markers of the original vs. fixed parts, unfortunately.

I'd say if the service manual says, go ahead and copy the text and/or post a screenshot of it, it'd fall under fair use.

 

[Hoagie]

Alright. This is what the manual says. And it’s exactly the layout of the two ROM-DIMMs I have.

 

[noglin]

This is very likely the infamous 5XXX/6XXX specific issue. I *think* that issue is actually with the CPU itself, a hardware bug in how atomics are handled, and will cause the machine to crash in a particular situation when there is an atomic operation and the address is residing in L2 (or is not residing in L2, do not recall). Few programs use atomics, so you would most likely mostly run OK. But I think maybe it was Netscape or a Network driver, that would cause 5XXX/6XXX with this issue to frequently crash if used.

I live in Spain, I have a working spare motherboard (5300, 603e 100MHZ, not recapped, compatible with 6200) I could trade for yours if you want, for me it would be interesting to reproduce the exact issue with code on such a board.

update: oh missed your last post, OK, there is a 5XXX/6XXX tester on Mac OS install CD:s, you could try run that to rule out it is not *that* problem: https://macintoshgarden.org/apps/updaters-–-mac-os-9-international-english

 

[pizzigri]

Hey Costantin,
sent you the ROM.
hopefully it’ll work!
all my beet,
Franco

 

[Hoagie]

Hey Costantin,
sent you the ROM.
hopefully it’ll work!
all my beet,
Franco

Thank you so much! I will keep you all updated

 

[Hoagie]

Hey Costantin,
sent you the ROM.
hopefully it’ll work!
all my beet,
Franco

Dear Franco, the Cache-ROM arrived today and it's working!

I am very happy, the Performa is running again!

Thank you all for your help.