The figtronix link broke because I asked him a question about his main rom adapter a couple weeks ago, and he updated the board, just the silkscreen not anything functional, and he removed the old link and made a new one. I don't know if that's just the way oshpark works or if he's just doing something wrong.
He ended up doing a bunch of stuff that I wanted for free and without asking, so I wasn't going to complain about a little thing like it's annoying having to keep finding out the new link! We ended up trading a lot of emails and he whipped up both the option rom board and the programmer adapter after I showed him the club100 links to the old EME option rom module. There were several rapid iterations of both of those and he did the same thing each time with those too, broke the existing link and made a new one. And it takes forever before they show up in the oshpark search too. (Oh yeah, don't trust that search. Find any working link to any board by that guy, then click on the guy's name, and THERE you see all his other boards, including all 3 M100-related, even though they don't show up in the search.) Anyway there's lot's of ways to skin the same cat of course. I like your board too. I actually assembled one of your boards too, but I'm using the figtronix at the moment, because I don't want a combined system and option rom, I want to be able to use the external accessible option rom socket to swap roms and install commercial roms, and I want the system rom to be socketed and re-programmable or at least swappable. I actually found ceramic uv-erasable clcc 27C256, but even replacing OTP plcc ones is better than needing a test-clip. One thing I should verify, maybe there IS actually room to solder your board on the motherboard and put a dip socket on the adapter, then trim the legs of the eprom a little so the eprom sits lower in the socket, does the resulting stack come out 0.55" or shorter? That would meet all my same wishes above. Takes a standard eprom, and the eprom is removable and reprogrammable with no special adapters. Ideally I'd like both the main and option roms to use the same kind of eprom. not plcc in one and soic in the other. There is just barely vertical room for a low profile plcc socket in the option rom, but low profile plcc sockets are surface mount so soldering them at home is not simple like the regular socket with thru pins. I have old commercial option roms that used a full dip28 eprom on a board. it's a tight fit but it works. The holes for the eprom are actually pulled in a little closer than the proper dip28 spacing, squished inside the half-holes on the edges which are at dip28 spacing. No room for a socket, so a board like that you could only re-program with either a test clip or a programming adapter, but that's no worse than what you already need for the soic board. But at least then that, along with your main rom board, means you'd have the same kind of part on both system and option roms. I mean IDEALLY of course, I'd love a REX, but I emailed the address on club100 a couple times and never got any answer, and the plans for REX aren't published like on oshpark, so oh well. Even if by a miracle one REX became available from somewhere, I still probably wouldn't want to invest time hacking with it if no one else could ever make use of the results. If the REX were reproducible at will and anyone could have one, THEN it would be a worthwhile target for hacking/developing. If not, then I'd rather just start a new public/open design even if it's cruder and reinventing the wheel. (And now that I say that, I realize I sure like my MISE, and that's basically in the same boat. The design is not public. The guy just happens to be actively producing and supporting it right now. So maybe I'm being inconsistent. At least I made my enclosure for the MISE public, including a slick non-trivial arrangement to hold the cf card reader which does not have any nice mounting holes or anything, if I do say so myself. ;) ) In the 102 of course I just stuck a plain socket in and a plain dip 27c256. No complications there. Same goes for late m100 too apparently though both my m100's needed the adapter. -- bkw On Mon, May 16, 2016 at 3:54 PM, Mike Stein <mhs.st...@gmail.com> wrote: > Thanks for posting those links. When I mentioned the various options for > adding/upgrading System and Option ROMs I wanted to include this one but at > the time the link at Oshpark didn't seem to work; I couldn't find any > mention on his Figtronix site either so I assumed they were no longer > available for some reason. Glad to see they're back and he's added a > programming adapter. > > One advantage of those boards over the board Bill and Steve are discussing > is that in a T102 you can add an Option ROM without removing the System ROM > chip; however, at the risk of being immodest I should point out what I > think are some advantages of the 'Combo' board: > > Whether you want to upgrade the System ROM and/or add an Option ROM in > either an old or a new M100/T102 you use the same board; no need > for separate System and Option ROM adapters. > > To (re)program the IC in an 'old' M100 you'll need another adapter to > convert the pinout back to standard JEDEC; no problem, just assemble > another adapter 'in reverse' as it were, with a socket. > > So the one PCB essentially does the same job as all three different > Figtronix ones; since you get a minimum of six boards you might save some > money. > > Finally, since it uses a standard 28-pin socket if you want to play around > with the System ROM code without burning/replacing/reprogramming the > E(E)PROM every time, replace it with a non-volatile RAM chip like the > Dallas DS1230Y or the FM1808 FRAM and a minor mod to connect R/W and you > can POKE around all you want.. > > m > > ----- Original Message ----- > *From:* Brian White <bw.al...@gmail.com> > *To:* Model 100 Discussion <m100@lists.bitchin100.com> > *Sent:* Saturday, May 14, 2016 11:42 PM > *Subject:* Re: [M100] ROM burning questions > > ...Re-post without pic... > > Old m100 takes a non-standard pinout, new m100 and all t102 takes a > standard 27C256 pinout. > > I just did an old m100 using this plcc adapter: > > https://oshpark.com/shared_projects/toQDqmVV > > I burned the Tandy 102 rom with y2k patches from the rex page on > bitchin100. > > The board is easy to assemble except the only hitch is you have to find > pin headers that have thinner round pins rather than the more common square. > > If you have a "new" m100, the chip number on the rom will not match the > number silkscreened on this board. In that case you don't need any > adapter, just put in a 27C256 dip28 directly, same as for T102. > > https://goo.gl/photos/GUKXgxxVGaUVt57k9 > > -- > bkw > >
