TI Mini Expansion System

[Artoj]

Hi All,

While going back over a few of the ideas I have being looking at, the V9958 with HDMI on the Tangnano20k is a definite goer. So I put together the I2C and a 16 bit GPIO with the Tangnano20k and make it fit inside the case, which I have called TI-TANGO. This is only a preliminary excursion to make sure it will all fit inside. A set of ribbon cables must be used to bridge parts of the circuit, H1/H2 and H5/H8 and H4 goes to the back of the Cartridge port, the only other soldering will be the sound port pin connection. The choice of a back plane is still to be decided while the addition of 32K is also another part not done as yet.

 

The I2C uses the spare pin of the TMS9901, giving you control of the I2C port by, R12 = >0000 with TB 12, TB SBO SBZ 16, TB SBO SBZ 17, which are enough to do the job, this still needs some prototyping.(as per S Conner). You will need to reposition the TMS9901 and add a socket, while the TMS9929/18 needs to removed and a socket added as well.

 

The GPIO uses 74ls259/74ls251 to give you 16 bits of I/O by, R12 = >0400 with CRU bits 0 to 15. (as per T Nouspikel)

 

Regarding the Tangnano20k you will need to follow the thread on the Atari forum for more details (as per Retrocanda76). Regards Arto

[GDMike]

Can it run mdos? When ready 

[Artoj]

51 minutes ago, GDMike said:

Can it run mdos? When ready 

As these are purely hardware mods and does not affect the operating system, I guess mdos will work fine. At present the V9958 needs no extra software as it will run in 9929/18 mode when running on a stock system, where the I2C and the GPIO will need assembly to be usable. I hope to use a myGROMY to add calls of these interfaces to TI Basic, I have yet to add 32K/MIDI/RS232 and a PIO port. I hope to make this a add-on board for any stock TI99/4A with a myGROMY chip, this should upgade the old TI99/4A without a giant PEB. Remember the I2C will give you a gateway to SD cards, USB and SPI converter chips. Regards Arto

Edited November 5, 2023 by Artoj

[+FarmerPotato]

On 11/5/2023 at 7:11 AM, Artoj said:

As these are purely hardware mods and does not affect the operating system, I guess mdos will work fine.

GDMike is joking--MDOS is for Geneve and uses 640K+

[GDMike]

7 minutes ago, FarmerPotato said:

GDMike is joking--MDOS is for Geneve and uses 640K+

Yeah 32K ain't going to cut it

[Artoj]

7 hours ago, GDMike said:

Yeah 32K ain't going to cut it

LOL, sorry i know little about MDOS or Geneve, but still i cannot fit the 32K at present as I have added a MIDI in/out, a RS232 port and a Infrared 2 way port (as suggested by Homeautomation and his work). The prime criteria was a low profile board that does not get in the way of the GROMS and gives you a few new options for those who want connectivity. Maybe a 2MB static ram, I think there is just enough room to fit it in. Regards Arto.    

[Artoj]

Here is the latest

 

[RickyDean]

5 minutes ago, Artoj said:

Here is the latest

 

Wow a Zeno board on steriods.

[Artoj]

Here is the rough of the back plane, the IR control would be at the front of the console.

 

Edited November 7, 2023 by Artoj

[Artoj]

Hi All,

I managed to fit the 2 Meg SRAM chip (including level shifter buffers - 3.3v to 5v) with the 32k as the first bank, the use of all the RAM will depend on using part of the GPIO ports (5 bits or more?). The Cartridge extension board will be revamped with sockets to fit all the leads. I will be spending a lot of time getting the SRAM banking system working transparently. The current design is only a detailed excursion and will need lots of testing to get it to fit and work without hiccups. I will release all the schematics and designs when I have passed the prototype stage. Regards Arto.    

Edited November 21, 2023 by Artoj

[Artoj]

Hi All,

 

I separated the 32k SRAM so you can disable it, in case you already have it. The 2 MB (256k x 8 ) is now free to use in anyway that you can via bank switching or such.  I will leave at this stage, as I need to work on the DSR for the PIO/TERNARY. Regards Arto. (I have made a few error in the diagram, I will update as soon as possible,Arto)

 

 

Edited November 12, 2023 by Artoj

[Alessio Iodice]

3 hours ago, Artoj said:

Hi All,

 

I separated the 32k SRAM so you can disable it, in case you already have it. The 2 MB (256k x 8 ) is now free to use in anyway that you can via bank switching or such.  I will leave at this stage, as I need to work on the DSR for the PIO/TERNARY. Regards Arto.

 

 

Can't wait to see this project finished on Github!

That's AMAZING.

[Artoj]

Hi All,

I have fixed the errors and added the mechanical situation with the Male Header Pins on the socket, the fit is within +- 0.1mm accurate. Regards Arto.

 

[Artoj]

Hi All,

I have just updated the Mini PEB Expansion and fixed the pin spacing to include the PI PICO or a ATmega32, while you can now choose to power each card from the external or the card edge power. One more short card I have yet to finish has header pins so you can connect the PICO/ATmega to the TI Bus. Regards Arto.

[Artoj]

Here is the Pin Header.

[Alessio Iodice]

On 12/27/2022 at 2:06 AM, Artoj said:

Hi All,

I just received my prototype board for the TI Mini Expansion System, it uses Peter Schuberts AT mini system cards from about 1986. I will post more info soon, here are some pics. Please note there are empty 40 pin sockets, these are there for adding a RP Pico or an ATMega 32, for future expansion. Regards Arto.

 

 

 

 

WOW!

I'm waiting for schematics

[Artoj]

7 hours ago, Alessio Iodice said:

WOW!

I'm waiting for schematics

Hi, as you can see by my latest posts, I had to sort out the first prototypes. The current version should have no issues, I am still deciding on a section in front of the boards where I could incorporate a whole standalone TMS9995 (or TMS99105 or FPGA) that can run everything without the 4A attached, so many possibilities and so little time LOL. I am also in the process of designing a AT motherboard form factor with the Mini cards, TI PEB cards and a single 16 bit IBM ISA card slot, and maybe a TI99/4A mother board slot or an extension for a S100 card slot, this is not a priority at all but has taught me much. This all should fit inside a standard AT case. I am also writing a DSR for my Ternary PIO project and learning GPL and Just having some fun until my workshop is finished, all schematics will be released as soon as the hardware is bullet proof. Some of these projects are revivals from over 30 years ago.

 

My main focus is on making a Ternary Logic/Computer Kit (as a teaching aid), this has been a long term goal all the rest are just additions and iterations, the TI99 just happened to be a great system to inter-grate and formulate a binary/ternary interface. As I have 2 more Volumes (300 pages each) to be released next year, from my book series "Talking to the Birds", which I had to put aside as the psychopaths of the world decided to push us down a dark alley for their nefarious ends. Within it's pages I was going to release my basic work on the Ternary Logic System, now covering at least 4 chapters, where now I am considering making a separate book, with much on interfacing binary, which I must include the TI99 as the target binary system. As I am self taught, I am both a student and teacher of this topic, which is only covered in a highly abstracted and a mathematically symbolic way that is highly esoteric and not quickly digestible. I hope to simplify and remove it's cloak of mystery, so we can make nuts and bolts reality, so I start with relays.   

On that note the TI99 has taught me how to design a functional computer system and I am in awe of the many that are here at Atari Age that are still making fantastic contributions to a so called "orphan", where in reality it was one of the vanguards that pushed the home computer into common knowledge and with it, a deep understanding of its technology, how fast we learn when we are given the right tools. Regard Arto

Edited December 22, 2023 by Artoj

[Artoj]

Hi All,

Here is another unfinished project, here is the schematic, please look for problems as I am almost finished. I must thank S. Conner, M. Brent, C. Randolph and J. Guidry for their hard work. Regards Arto.

 

[+dhe]

On 12/21/2023 at 6:44 PM, Artoj said:

my book series "Talking to the Birds"

 

Hi,

 I think this is the first mention of a book series.

 What is it about?

 

[Appeelicious]

Insomnia has led to me digesting the thread. Thank you for the interesting diversion. You certainly have your fingers in many pots. I don’t have the expertise to make comment beyond expressing excitement for your work. Thank you for keeping us apprised along the way!

[Artoj]

5 hours ago, dhe said:

What is it about?

I do enjoy the hands on approach to using computers and do not own a mobile phone,  I know too much about RF to allow it destroy my sensibilities, LOL. 

 

As the Author, my simple synopsis might be enough:

 

A compilation of diverse studies in the underlying designs and principles behind the Arts and Sciences, taken from an Artists perspective on the world he studies. A book where Art, Engineering and the ancient world meet. Highly illustrated, with artwork, numeric tables, geometries, designs and schematics. This is Volume I.

 

https://www.amazon.com.au/Talking-Birds-Compilation-Studies-Artwork/dp/1876406038/

 

I finished writing it in 2013, while I also had two more volumes almost complete by 2016, the madness I had written about actually occurred. I suspended publishing and decided to further my many studies in more detail and outline a new approach to the multitude of broken scientific,artistic and technical issues that have plagued our institutions. I am not alone in all my endeavours and found much commonality with the Retro computing, fringe science, alternate history and traditional artistic communities. We are at the precipice of a new paradigm in the Arts and Sciences and the road is still being mapped, all I can say is I just keep my head clear, work hard and let the law of reciprocity and karma be my guide, while I keep a stern hand on the truth, and allow the current world events to unfold. Regards Arto.          

[+Ksarul]

13 hours ago, Artoj said:

Hi All,

Here is another unfinished project, here is the schematic, please look for problems as I am almost finished. I must thank S. Conner, M. Brent, C. Randolph and J. Guidry for their hard work. Regards Arto.

 

It looks like you are using an inverted bank optioning here with seven latches. You can eliminate a chip by switching to a 74LS377 which has one more latch than you need, and it uses non-inverted outputs (compatible with pretty much every ROM file out there ending in "8"--pretty much, because my Yellow boards use all 8  of the 377 latches, so a few files out there will be larger than your board allows). In this mode, you would have no need for any of the three manual switches, as you could use jumper blocks for all chip size selections--and the available latches would be able to create a single group of banks that would fill the 27C080. I did something similar with the Red boards, but I used a 74LS378 (25LS07 is an alternate chip for this) which only has six latches, so I needed a single switch to select between two 512K spaces on the board in place of a seventh latch.

[+Ksarul]

One other note: 74LS377, 378, and 379 chips have indeterminate states on startup. Most will start in the first or last banks, but some small fraction of the chips will start in some truly random bank. I usually use a bank test program written by Tursi to verify which bank each chip starts in and I use the really odd ones for other projects, keeping the ones that start in the first or last bank in my boards.

[Artoj]

4 hours ago, Ksarul said:

You can eliminate a chip by switching to a 74LS377

Thank you Ksarul, about a year ago I did a complete cartridge design using the 377, for the life of me I cannot find any one of the files, so I went back to the original work and used the 379 as was used by Guidry and this time saved many other versions as well. I have V3 marked as the 377 use. Thank you again, I will post the update soon, regards Arto.

[Tursi]

Yeah, the 'inverted' bank order that the 379 supports is pretty much deprecated now, nobody releases images using it.

 

Edited December 27, 2023 by Tursi