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]
<mailto:[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
<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
<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
<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 <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
<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 <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
<https://archive.org/details/M100SIG>
>>> , club100, scanned magazines on archive.org
<http://archive.org>, and general google for
>>> info on other vintage computer sites. I don't have a link farm
handy
>>> to list those.
>>>
>>
