Justin, On your T200 ram module, what kind of pin do you use? I'm always on the hunt for low cost pins... thx Steve
On Fri, Jul 9, 2021 at 9:28 AM Justin Poirier <[email protected]> wrote: > Some quick snaps I loaded to my Google Drive for paroosal: > > The SOIC EEPROM adapter/programmer: > > https://drive.google.com/file/d/1KDG4YevQZBaP72dhnJJwGXZKxzJsfhNu/view?usp=sharing > > The PROM-based 8-slot ROM adapter (in a T102): > > https://drive.google.com/file/d/138PiJQOmxYbh2wuQFnczIsGsQdF5HhB6/view?usp=sharing > > The 24k T200 memory upgrades I make and have been selling on eBay for > years. (You've probably seen these if you use eBay at all.) > > https://drive.google.com/file/d/1mn1irtPzuqOzBhGmKGh6pm7r91rbbd3r/view?usp=sharing > > Any questions, let me know! > > --Justin > > On 7/9/21 8:37 AM, Pawel Radomychelski | ExPLIT wrote: > > I think many of us would be happy to see some images of your work. > > > > I don't ask for a manual, that would be very time-intensive, but if you > could make some photos - that would be gr8! > > > > Thanks! > > > > Pawel > > > > > > On Friday, 9 July 2021, Justin Poirier wrote: > >> My first run was using a 28C256 on a SOIC-28 chip. Same thing you did, I > >> used a resistor to hold /WE so that I could pull it with the burner when > >> I wanted to erase/re-write the image. But, also like you said, those > >> chips are $10 each now and hold a single image. I built the carrier > >> (actually, designed in KiCAD and sent to GoldPhoenix for fab), soldered > >> the SOIC on and burned it using a DIP-28 to "Molex" adapter that I built > >> out of Cat5E wire and a DIP header, with 1" long "fingers" on the other > >> size made out of gold-plated spring wire used for craft jewelry. The > >> carrier clips into that 28-pin finger arrange, which has all the pins > >> for a 28C256 DIP-28 re-mapped to the Molex pinout and the burner just > >> sees it as a DIP-28. Works pretty good, but it's a pain, and it's > expensive. > >> > >> So the PROM version uses a AT27C020 in PLCC-32 format on a different (of > >> course) carrier, and via a suite of programs I wrote in Perl, builds a > >> single ROM image out of 8 32k images, which I burn in the TL866-II. Then > >> I solder the chip to the carrier, and the DIP switches select which > >> 32-image is available at any given time. Simple enough, and it works > >> very nicely. I have several of my prototypes in my T102 and several > >> T200s. No complaints. The chip is $4 at Digikey, and as long as I get > >> the image right, it's one-and-done. > >> > >> This is a working project. It's done, except for the actual ROM images. > >> I have the boards fabricated, the chips on hand, and have a half-dozen > >> working prototypes on my bench. I know the REX is a great device, but > >> sometimes K.I.S.S. wins out in my head. Sometimes I just need a ROM in > >> that slot all the time, and since I have a good number of Ts that are > >> all used in various ways, I can't justify putting a REX in each. > >> > >> --Justin > >> > >> On 7/8/21 3:19 PM, Brian K. White wrote: > >>> On 7/8/21 10:06 AM, Justin Poirier wrote: > >>>> It appears that Club100 on bitchin100 only have a handful of ROM > >>>> images. Where do I go to find SuperROM, Disk+ and those others? They > >>>> have generic enough names that Google has been of very little help. > >>>> > >>>> I have been working on an inexpensive carrier solution (for myself, > >>>> mostly) that will hold (8) ROM images that are selected with a group > >>>> of DIP switches on the carrier itself. Nothing fancy, but if I like > >>>> the results, I could probably crank them out, burned and ready, in > >>>> the $20-$25 range. Not committing to anything at all, since I’m still > >>>> in prototyping, but with (8) ROM slots, I’m not sure what to put in > >>>> them. So far, I made one that has TS-DOS, Ultimate, Cleusseau and > >>>> TS-Random. And since I have twice as much space as all that, it > >>>> includes those titles in both the M100/102 versions as well as the > >>>> M200 version. That seems wasteful. Maybe I’m wrong! > >>> How are you connecting up to burn them? Through the edge connectors > >>> with a reverse pinout adapter? DIP-28 test clip on the outside edges > >>> with the wires arranged into a reverse pinout adapter? Or are you just > >>> burning before soldering and no re-writing after that? > >>> > >>> I made this single-rom carrier that, since it's an SOIC package, and I > >>> have a resistor rather than a trace for /WE, is easy to just connect > >>> normally with a soic test clip to program. > >>> http://tandy.wiki/Teeprom > >>> > >>> > >>> But that 28C256 is now OVER $10 just for a single 32k, and I'd like to > >>> try to ditch the requirement for the test clip if possible, and > >>> definitely don't want to require an actual Molex socket. (I have molex > >>> sockets, but I'm trying to make a design anyone can use, not just > >>> something for myself) So I tried this > >>> https://github.com/bkw777/Teeprom/blob/master/Teeprom2.md > >>> > >>> 4 or 8 roms (that's just a 4-rom version but 8 would be a > >>> straightforward progression from there) and no special parts needed, > >>> and it's even both cheaper and more convenient than the soic-28 test > >>> clip, and the flash part is both more readily available (multiple > >>> manufacturers still) and just over $1 instead of over $10. > >>> > >>> > >>> Which *almost* works as envisioned. The programming adapter is built > >>> out of all normal off the shelf parts, and the connection between the > >>> programming adapter and the carrier is made by dint of having the > >>> holes on the carrier be offset staggered so they work against each > >>> other. I think I just need a different stagger pattern, and slightly > >>> more offset to the stagger. I was able to get it to work by tediously > >>> testing each pin for connection to identify a handful that didn't > >>> connect, and bending the pins manually until they all worked. > >>> > >>> Not practical. > >>> > >>> But that was only the first proof of concept, no iteration yet, so > >>> maybe with a little dialing-in the idea would work out. > >>> > >>> But then again maybe that many little pins in that kind of arrangement > >>> is just never going to be reliable. > >>> > >>> So I was thinking of next either using pogo pins, because those are > >>> actually cheap now, or using long wire-wrapping pins to make something > >>> that can act like a DIP test clip that can just contact all the edge > >>> contact pins on the outside like a normal socket does. That would make > >>> the carrier a LOT simpler! > >>> > >>> I really thought those pins were slick ;) If they would just all > >>> actually make contact, it does pretty much work as expected, meaning > >>> it wasn't too hard to build and that carrier pops right onto the > >>> programmer simply and even with polarity enforcement. > >>> > >>> > >>> I've gathered links to all the roms I've seen here: > >>> http://tandy.wiki/ModelT_roms > >>> > >>> Most you can get all in one spot from Steve's REX docs on bitchin100 > >>> (link in there), but there are a few other oddballs. > >>> > >>> Documentation has not been gathered into one convenient spot that I > >>> know of, other than club100 which is a good start but incomplete, and > >>> not going to get any better, it's a static site now just being > >>> presereved. > >>> > >>> You get info from searching through the M100SIG > >>> https://archive.org/details/M100SIG > >>> , club100, scanned magazines on archive.org, and general google for > >>> info on other vintage computer sites. I don't have a link farm handy > >>> to list those. > >>> > >> > >
