..re REX. IF I could release it to oshpark I would. In fact the boards are there. The problem is... I doubt people will be successful soldering fine pitch. Do you want to try? The chips can be purchased on ebay or digikey. If you want to try I will release the board design(s).
Steve On Mon, May 16, 2016 at 8:33 PM, Brian White <[email protected]> wrote: > 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 <[email protected]> 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 >> To: Model 100 Discussion >> 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 > >
