At the very least, I mean to preserve all the original reference parts and docs from you Steve. Right now my original verbiage about the AM29F800 part is commented out but it's actually still there if you hit "edit". And I think I'll make a whole separate page listing everything so it's all visible and easily referred to, but out of the way behind a link to keep the main recipe as uncluttered as possible.
Also I just realized there is a pretty simple hack for port_en right now with the existing design, because C1 is unused. 1 - Scratch out the trace between R3 and C1 2 - Install R3 to bridge C1 and R3 in place of the cut trace. 3 - Solder bridge the two pads of R3. Now the unused R3 pad is at least a little more reasonable test point to aim for to pull up port_en. On Oct 21, 2017 8:19 PM, "Stephen Adolph" <[email protected]> wrote: > Probably warrants some extra due diligence. Am29f800 is all that has been > used to date. Saying a new chip works, while likely, should be done a bit > carefully. > Saying that I would expect any follow on flash parts to be compliant with > the dominant vendor. So seems reasonable. > > On Saturday, October 21, 2017, Brian White <[email protected]> wrote: > >> That's awsome. Great to know even one other part number just for >> reference, let alone the convenience of making a single order that has the >> full iit. >> >> I say absolutely add it to the digikey cart and save it as a new shared >> cart, and maybe leave the original part number and verical link as a >> reference somewhere on the wiki page. >> >> I also like to fill in the customer reference field for each part with >> the matching silk screen label. For the replacement ram chip for quad I put >> "Replaces TCM10051". So When a new user orders the kit it's >> paint-by-numbers. >> >> I'll update all that stuff, but just for the record I was always >> specifically hoping for other people to flesh it out and add to any of >> those pages. That's why it's a wiki with a functional account registration. >> >> I know they are sketchy because I was just trying to get the key info >> down while working. But the wonderfulness of a wiki is once you get >> anything at all to start with, it's super easy to improve over time by just >> adding 5 minutes of work now and then, and fix up like one paragraph or one >> link etc. I've been tweaking it a little lately with for instance a little >> clearer pointers to the .jed and flash files, and like just yesterday >> making it explicit to use build 162 etc. Still could be even clearer. >> >> Maybe I'll make a tangent more-info page about the flash chip that lists >> known compatible parts and a description of what properties matter. Links >> to data sheets, explaination what to look for in the data sheets. So we >> have some part actually in the order form, but a page of info about how you >> would pick a part from scratch when that order form no longer works. >> >> Same for the cpld, except I myself know less about those, so I'd be >> limited to the gross electrical specs. >> >> Anyway, thanks for figuring out another part. >> >> -- >> bkw >> >> >> On Oct 21, 2017 5:14 AM, "Jim Anderson" <[email protected]> wrote: >> >>> I finally got a chance to build a second REX tonight on my own (kids are >>> off at their mother's house for the weekend). >>> >>> Two wins: first of all, the voltage regulator I thought I messed up last >>> time is actually OK, and I was able to straighten the pins, solder it down >>> to a fresh PCB (along with C4) and give it a functionality test. >>> >>> Second, I thought I'd try out one of the MX29F800CBTI-70G chips I >>> ordered from Digi-Key last time, and it works perfectly. I've loaded every >>> ROM image I can find and a bunch of my RAM images from VirtualT into it and >>> so far no problems switching between any of them. I'm not sure what else >>> needs testing to verify it, but I was honestly half expecting it to barf >>> when I tried installing the REX software load. >>> >>> The chip is a Macronix MX29F800CBTI-70G and the Digi-Key part number is >>> 1092-1022-ND. They're not quite as cheap as buying the AMD chips in lots >>> of 10 off eBay, but for someone who just wants to build 1-3 REX modules for >>> their own use I thought it might be convenient to not have to place an >>> order with another parts supplier or from China to get a couple of flash >>> chips. >>> >>> Brian, I could add a mention of this to the Building a REX wiki page, or >>> leave it for you to add if you prefer. I don't know if it would be nicer >>> to make it part of the pre-loaded Digi-Key cart you linked to, or just >>> mention it separately. >>> >>> >>> >>> >>> >>> >>> >>> jim >>> >>>
