32k sideport expansion

[+arcadeshopper]

yeah I'd like to see some sort of storage that makes my nanopeb useless, secondary would be a serial port or tcp interface

 

Greg

[Sinphaltimus]

yeah I'd like to see some sort of storage that makes my nanopeb useless, secondary would be a serial port or tcp interface

 

Greg

Precisely.

[Asmusr]

Would it be possible to build a storage module using Arduino components only for the hardware?

[+arcadeshopper]

Would it be possible to build a storage module using Arduino components only for the hardware?

 

Hardest part would probably be the DSR

 

Greg

[+jedimatt42]

Would it be possible to build a storage module using Arduino components only for the hardware?

Hardest part would probably be the DSR

 

Greg

Arduino's don't have external address or data buses. So, I think you would have to simulate that with the GPIO pins... I would imagine you need to create a DSR external to the arduino, and with some logic map the GPIO pins in creating a memory mapped, parallel io port. I imagine, then code in the DSR copy the PAB through to the Arduino, it could act, and then signal completion, and code in the DSR would then copy out the response.

 

I've read repeatedly, that GPIO just doesn't work to bit-bang simulate memory... But then Tursi basically does that with the AVR in the UberGrom, although GROM is, if I understand, accessed with even more wait-states. So, given that 8-bit side of the 4A requires only something like 450ns (I'm using my recollection not a reference) responsiveness, it might be possible. So, it might be possible to even keep the DSR inside the Arduino, only because the TI is sooo slow...

 

I have a couple Teensy 3.6 devices, that other than logic-level conversion to 3.3v, I hope to try something like this with. It is 180Mhz. But...

 

I have something else in mind as my first daughter board. I've posted this intention outright, once hidden in white font on some thread back in September, and anecdotally elsewhere. I actually don't think anyone here on this forum would care about it.

 

-M@

[+jedimatt42]

Oh, but I should repeat: As soon as TI dumped the 4A, it became an open platform... And header on the side of my 32k board matches the pinout for the TI sideport. So, please, go nuts!

 

-M@

[Tursi]

AVR's are more than fast enough for GROM emulation - even with the internal 8MHz clock my code's 3 times faster than the console GROMs, and that's with abstractions and mapping. But they would have a really hard time keeping up with the standard memory bus (I wasn't able to convince myself they are even quick enough to slam on the HOLD line, but they might be ). Also true is that you can externally clock AVRs, and some of the bigger ones top 100MHz. That'd be fast enough.

 

Or just use an ARM for that. Much faster, just as cheap, lots of I/O, easy to program...

[Asmusr]

Oh, but I should repeat: As soon as TI dumped the 4A, it became an open platform... And header on the side of my 32k board matches the pinout for the TI sideport. So, please, go nuts!

 

-M@

 

Thanks. So if Arduino is not the answer, can anyone outline the simplest way to build a storage module? There has been talk about this for years, but I have never seen a schematic or anything. I claim complete ignorance when it comes to hardware projects by the way , but I think it would be interesting to work on a DSR.

[+arcadeshopper]

 

 

Arduino's don't have external address or data buses. So, I think you would have to simulate that with the GPIO pins... I would imagine you need to create a DSR external to the arduino, and with some logic map the GPIO pins in creating a memory mapped, parallel io port. I imagine, then code in the DSR copy the PAB through to the Arduino, it could act, and then signal completion, and code in the DSR would then copy out the response.

 

I've read repeatedly, that GPIO just doesn't work to bit-bang simulate memory... But then Tursi basically does that with the AVR in the UberGrom, although GROM is, if I understand, accessed with even more wait-states. So, given that 8-bit side of the 4A requires only something like 450ns (I'm using my recollection not a reference) responsiveness, it might be possible. So, it might be possible to even keep the DSR inside the Arduino, only because the TI is sooo slow...

 

I have a couple Teensy 3.6 devices, that other than logic-level conversion to 3.3v, I hope to try something like this with. It is 180Mhz. But...

 

I have something else in mind as my first daughter board. I've posted this intention outright, once hidden in white font on some thread back in September, and anecdotally elsewhere. I actually don't think anyone here on this forum would care about it.

 

-M@

 

SNIPE HUNT!

[+jedimatt42]

Ok, fine, I'll think about this a bit now... And I'll think out loud, cause that is fun... ( if typing is out loud )

 

Thanks. So if Arduino is not the answer, can anyone outline the simplest way to build a storage module? There has been talk about this for years, but I have never seen a schematic or anything. I claim complete ignorance when it comes to hardware projects by the way , but I think it would be interesting to work on a DSR.

Teensy's just my preferred 'Arduino compatible' board. Arduino is mostly just a development environment. Lots of different hardware can be programmed in that environment.

I think we are saying, it should be possible. Or it is really close to possible.

 

So, take the Teensy 3.5.. it is a 120Mhz ARM. It has a convenient 42 breadboard friendly GPIO pins, all digital GPIO pins on it support interrupts. It is a 3.3v environment, but all GPIO pins are 5v tolerant. It has a 3.3v regulator on board, so voltage in can be up to 6v. It has a micro USB port, so it is easy to program, with no hardware other than your PC.

It also has a microsd card reader on board, and pinouts for a USB host port. We could attach a thumb drive there... but why, we can use microsd...

 

So, select 8 of the pins to be data, and wire them up to a 74HCT245 buffer chip. Pretty much like I did for the SRAM.

wire all of the other sideport signal pins to other GPIO pins on the Teensy. Wire the grounds, wire my header's +5v pin to the Vin pin on the Teensy.

 

Now, it's all a software problem

 

An interesting experiment I may try reaching for, is simply using the Teensy micro-controller to detect CRU DSR selection, and enabling the data buffer chip, and trying to host a DSR ROM loaded off of the microsd card.

If that can be accomplished, then probably extend the hardware to support the RTC, which I think is just a coin-cell holder to the 3v RTC power input.

 

And from there... Just keep updating software to expose features. I personally would implement a 'harddrive' like storage based on TIFILES in a FAT file system on the microsd. I would aim for that before providing any DSK1 hook. Good TI software doesn't care about DSK1. Not in it's heart anyway.

The RTC could be exposed as a CLOCK device. The USB programming port can be exposed as a Serial device ( although it wouldn't likely be compatible with things that program to the 9902. )

 

I would also then put this on a PEB card. And then have to learn how to re code the Master DSR in MDOS, cause what I really want... and the only reason I work on this hardware, is to someday have a hard-drive like storage solution for my Geneve.

 

Goals are good. I have no idea how real a plan like that is. Maybe if I built a pcboard to handle the hardware, an assembly user might rock out all the DSR hurdles.

 

-M@

[sometimes99er]

Oh, but I should repeat: As soon as TI dumped the 4A, it became an open platform... And header on the side of my 32k board matches the pinout for the TI sideport. So, please, go nuts!

 

-M@

 

Since the contents of the ROM and GROM are so specific to the 4A, they would also be open ?

 

 

 

 

[Sinphaltimus]

yeah I'd like to see some sort of storage that makes my nanopeb useless, secondary would be a serial port or tcp interface

 

Greg

 

With nanopebs now available again, this comment concerns me, do you not like your nanopeb? I know it's not exactly mass storage like an HDD so perhaps that's the reason for this comment? I dunno, seriously considering purchasing a nanopeb and trying to get as much info as I can from members here (I already read the wiki twice)

[Omega-TI]

After using Matt's 32K device for awhile:

 

I've found that when it comes to quality... IT"S GREAT! I have absolutely no issues whatsoever with it. It's rock solid, well designed and constructed. Simply put, it always works.

 

The design does NOT 'lock you in' and limit your ability to expand and grow in the future.

 

It's a great price!

 

When paired a FlashROM 99 and it's HUGE online collection of free software, it already does 95% of what the average user does. Once the expansion modules start rolling out for this thing... look out, I think it's going to be an amazing ride.

[+jedimatt42]

With nanopebs now available again, this comment concerns me, do you not like your nanopeb? I know it's not exactly mass storage like an HDD so perhaps that's the reason for this comment? I dunno, seriously considering purchasing a nanopeb and trying to get as much info as I can from members here (I already read the wiki twice)

Nanopebs exist. A storage and serial solution for my 32k doesn't. The nanopeb use case is the same as a stock TI PEB. Versatile, But considerably less expensive. My 32k boards target use case is hopefully two: Cartridge gaming, and hardware hackery.

 

-M@

[+arcadeshopper]

With nanopebs now available again, this comment concerns me, do you not like your nanopeb? I know it's not exactly mass storage like an HDD so perhaps that's the reason for this comment? I dunno, seriously considering purchasing a nanopeb and trying to get as much info as I can from members here (I already read the wiki twice)

I don't like the disc emu in the nano/cf7 it's clunky and user unfriendly. Would much prefer a flat fs like hdx or a hard disk. Then u can catalog in dm2k instead of having a printout of all your disk images to remember number 43 is rasmus games.. Etc

After using Matt's 32K device for awhile:

 

I've found that when it comes to quality... IT"S GREAT! I have absolutely no issues whatsoever with it. It's rock solid, well designed and constructed. [emoji106] Simply put, it always works.

 

The design does NOT 'lock you in' and limit your ability to expand and grow in the future.

 

It's a great price!

 

When paired a FlashROM 99 and it's HUGE online collection of free software, it already does 95% of what the average user does. Once the expansion modules start rolling out for this thing... look out, I think it's going to be an amazing ride.

 

Sent from my LG-H830 using Tapatalk

[+arcadeshopper]

Nanopebs exist. A storage and serial solution for my 32k doesn't. The nanopeb use case is the same as a stock TI PEB. Versatile, But considerably less expensive. My 32k boards target use case is hopefully two: Cartridge gaming, and hardware hackery.

 

-M@

Yep that's why I had three. Now two of them. I use it for hdxs and browser too. Which is nice.

 

Greg

 

Sent from my LG-H830 using Tapatalk

[Sinphaltimus]

Nanopebs exist. A storage and serial solution for my 32k doesn't. The nanopeb use case is the same as a stock TI PEB. Versatile, But considerably less expensive. My 32k boards target use case is hopefully two: Cartridge gaming, and hardware hackery.

 

-M@

 

I will exercise patience an see what developes. I have a console with a peb w/fdc & 32k - I have another console for your 32k sideport and I just ordered an f18a for it. I don't think I need to replicate the functionality again. Holding out for mass storage.

[Asmusr]

An interesting experiment I may try reaching for, is simply using the Teensy micro-controller to detect CRU DSR selection, and enabling the data buffer chip, and trying to host a DSR ROM loaded off of the microsd card.

If that can be accomplished, then probably extend the hardware to support the RTC, which I think is just a coin-cell holder to the 3v RTC power input.

 

That sounds cool. It would be great to have a platform for building 'soft' DSR controlled cards. What is the data buffer chip?

[+jedimatt42]

The data buffer chip is a 74ls245 or 74hct245.

 

It allows blocking the rest of the circuit from the data bus, like when other things are using it, and boosting the data bus outputs. The Teensy output is only 3.3v ttl, it just seems wise to bring that up to 5v before sending back into the console.

 

-M@

[+Lee Stewart]

I use my nanoPEB most of the time when I am on RI. I do agree with @arcadeshopper regarding the clunky nature of access to disk images. It is, however, completely analogous to the real PEB with three disk drives. The only difference is that you cannot see disk labels on each disk that would aid in deciding whether to insert a disk into one of the drives.

 

It is irritating to have to get out of fbForth 2.0 (or any working environment, for that matter) to mount a different volume in (“insert a different disk into”) one of the three available disk “drives”. I may soon write some routines in Forth to do the volume mounting from within fbForth 2.0.

 

...lee

[+Ksarul]

That's a really good idea, Lee!

[Asmusr]

The nanoPEB/CF7 is a great device - I have 3 of them. But it would be better to have an open source design that people could build themselves if supply was failing and we would know how to repair.

[+OLD CS1]

The way I see it, there has been call for a "mini PEB" and Matt's 32k cart presents a vehicle to that end. Including building a PEB-compatible back-plane to hold a couple of real PEB cards, if desired. The nanoPEB/CF7+ is a great all-in-one device replacing the standard functions of a PEB, but with Matt's Jedi Port we could even go so far as to create a mini SAMS^† or mini FDC^‡, and much more.

 

^† jediSAMS

^‡ jediFDC

 

(jedi232, jediPIO, jediUSB, etcetera ad naseum.)

[Tursi]

 

Thanks. So if Arduino is not the answer, can anyone outline the simplest way to build a storage module? There has been talk about this for years, but I have never seen a schematic or anything. I claim complete ignorance when it comes to hardware projects by the way , but I think it would be interesting to work on a DSR.

 

Have a read through Theirry's page - he goes into good detail about the parts necessary to interface, at least on the PEB side. Most of what he describes is applicable to the side port, too. Most of what I understand I learned by studying his examples.

 

http://www.unige.ch/medecine/nouspikel/ti99/titechpages.htm

[Tursi]

 

Since the contents of the ROM and GROM are so specific to the 4A, they would also be open ?

 

Discontinuing a product doesn't make it open. The fact that TI issues licenses to the people who ask strongly suggests they are not releasing it to the wild, even if they aren't chasing after actively right now.