trag wrote: > <snip> > > It might be possible to identify the destination of the unconnected > wires using the information above. It appears that the CPU and > faster cache are on the add-in card. So, presumably, the wires > needed are probably control lines for the cache, and maybe two address > lines from the memory controller? It would take a lot of circuit > tracing, but I think it would be doable. Probably about 20 - 40 hours > of work, would be my guess. > > My approach would be to first trace what the 32K cache is connected to > on the logic board. Get a datasheet for the SRAM chips used and use > that to give some idea of what's what. <snip> > > The other interesting part of this is that fast SRAM is cheap now > days--ranging from $1 for a 256K module at OWC (has the chips which > would take the IIfx to 128K) to a couple of dollars for a 256K or 512K > SRAM chip such as was used with the G3. If the wiring could be > mapped out, it might be fairly easy to make a new cache expander for > the IIfx. It wouldn't be economical (development cost vs. tiny > demand) but it might be fun. > > Jeff Walther
Well, that does seem like what's on the addon card. Some kind of cache RAM looking thing with a passthrough for the processor, and a header that shoots wires out. They are still connected at the connector end, so I'd be fully able to trace then from the one end. I don't personally have a lot of experience with such things, though I do know my way around a datasheet. It'll be a little awhile before I have the time to mess with it, but I'll have to dig them up. I can tell pretty well where the extra wires were attached thanks to the solder scarring, but I don't know *which* wires attached to which pins. And I'd rather not try trial and error. If you have any handy links to datasheets, it'd save me some time. Scott --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
