Micron Xceed docs on ebay

[bdurbrow]

There are FPGAs that can do DVI and HDMI directly; and I have here an FPGA dev board (Papillo with an Arcade MegaWing) that does VGA via a R2R ladder.

 

[Byrd]

It's been a month since the auction ended and there doesn't appear to be much info made available ... did anyone get much from the seller?

 

[kreats]

Tried to contact the seller twice but no joy. Even offered cash for some scans.

 

[danpoarch]

Weird. Here's an email thread between Gamba and some other folks talking about an eBay purchase of the Micron XCEED plans in 2002. Does anyone know what happened to that set of plans? I have to assume they're a different set based on the recent seller's claim of being a Micron engineer. Not to point any fingers, I'm just trying to understand if these plans already exist in someone's archive.

Maybe we're like Jean Reno and Robert De Niro in Ronin and we're chasing the steel briefcase for the wrong reasons, or maybe it's the wrong briefcase...

https://www.mail-archive.com/search?l=compact.macs@mail.maclaunch.com&q=subject:%22Re%5C%3A+SE%5C%2F30+Dreams%2C+Tricks+and+Repairs%22&o=newest&f=1

 

[trag]

Well that brings back memories. That's the thread that ultimately led to Gamba and me collaborating on the IIci ROM for SE/30.

Someone sent me the set of info mentioned in that discussion. It is a full set of schematics for the Xceed video card, but there's no info on the custom chip internals. So you know how the pins of the chips are connected, but are still in the dark about how the chips do what they do. Oh, there's some theory of operation and one can kind of suss out what the chips must be doing, controlling the memory and buffers, but it doesn't really put one any further along than designing it from first principals.

IT IS NOT A CLONABLE DESCRIPTION.

I can't say whether this recent set of plans is similarly deficient, but it sure sounds like the same deal.

 

[kreats]

Well there is some source code included and the guy was the engineer responsible - so probably the last chance to ever get detailed info about the card.

Having the source for the drivers might make a workalike possible at least. There is also a disk there that says "Bart code" -  might even include the HDL code for the chips.

PS: care to share the resources you have?

 

[trag]

I put a stuff it archive of the floppy at https://www.prismnet.com/~trag/Classic Mac/SE30/

There's a listing for the card's firmware and driver, IIRC, but nothing about the internals of the PLDs or ASIC.

 

[joethezombie]

The only thing I can add, is the XCEED I found had some QC markings on the chips.  The Micron GAM 0398 AIS has a sticker that says "grayscale OK", and the Bt473KPJ80 has the resolutions written on it.

 

[Scott Squires]

trag, thanks for uploading your floppy! The software is as important as the hardware design. And the source code can give some clues into the hardware as well.

 

[trag]

Well, I had forgotten I have it. That was 13 years ago.

 

[danpoarch]

Well that brings back memories. That's the thread that ultimately led to Gamba and me collaborating on the IIci ROM for SE/30.

Trag - saw you in there, wasn't trying to call you out. If anything, that thread is a little hard to read so I couldn't tell who knew what. Thanks for your honest reply and thanks for digging through the sticky black tar of memories about something you wrote years ago. Thanks for the floppy image, too.

The Vintage Mac wing at the maybe-someday Smithsonian Museum of Computer History should have a Gamba room and a Trag room. ; )

 

[danpoarch]

The only thing I can add, is the XCEED I found had some QC markings on the chips.  The Micron GAM 0398 AIS has a sticker that says "grayscale OK", and the Bt473KPJ80 has the resolutions written on it.

Micron GAM 0398 appears to be a Micron part number, but not any kind manufacturer reference. This is some sort of programmable logic, do we know the make/model of it? Also, this is the soldered chip in the top right corner(?), do we know what the socketed chip closer to the DIN connector is? I assume that's some sort of ROM or glue logic, correct? Are any of these dumpable? (My degree says EE, but my experience says spreadsheet monkey)

Edit: On these older PLA chips, the programming was burned in wasn't it? Finding this same chip today, even if we had a ROM dump, might not necessarily do us any good? Again, out of my depth here.

 

[trag]

Trag - saw you in there, wasn't trying to call you out. If anything, that thread is a little hard to read so I couldn't tell who knew what.

No worries, Dan. I didn't feel persecuted or even pointed at.

I too had trouble sorting out that thread's presentation. Probably doesn't help that I read it on a tablet. The formatting was a mess.

 

[kreats]

Thanks trag - don't suppose there is any chance of some scans of the remaining material?

 

[trag]

Thanks trag - don't suppose there is any chance of some scans of the remaining material?

The glass fell out of my SCSI scanner years ago and I've never replaced it.   I'll keep it in mind as a to do, but honestly, the other stuff just isn't that helpful.  Maybe if one is doing repairs on an existing Xceed card, but even then, we've seen several variations on the card with different amounts and arrangements of VRAM, so the schematics on these sheets only apply to one particular model.

 

[just.in.time]

Not sure if anyone is still following this thread.

The pages here seem to match up to some of the pages visible in that eBay listing, as well as the Micron Xceed ROM.sit file containing a folder called Rob is Barts Friend, looks interesting but I haven't had a chance to actually look through the files.

https://archive.org/details/MicronXCeedTechDocs/mode/2up

Hope this is useful to someone, looks like it was uploaded almost a year ago (April 30, 2019).