Upcoming Jaguar Game Drive Cartridge

[SainT]

Just a quick update, it's been a bit quiet for a while from me. Lots of things on at the moment, just never seems to be enough time in the day! Hence it's gone midnight again. Gah.

 

I've been working hard on the EEPROM save game support, and it's getting close to working. I've had to implement what I'd describe as an EEPROM to SPI bridge in the custom chip. It basically converts the data fed into the EEPROM bus into a series of bytes which are transferred over SPI to the microcontroller. Annoyingly the EEPROM is microwire, which has a variable length bit stream, whereas SPI is fixed. So it's difficult to read the EEPROM bus directly from the microcontroller (at least the one I am using), so hence I opted for the bridged approach.

 

I've finally just got a write packet being received correctly at the microcontroller, being sent from the Jaguar over the microwire EEPROM bus. Next is decoding the EEPROM packets as they come in and sending back suitable data for read commands and storing write data. As usual it's been amazingly time consuming to get it all working... there's something magical about developing hardware. It seems even seemingly simple tasks can often be a pig to get working seamlessly.

 

The concept here is that the microcontroller is basically acting as the EEPROM with a bit of magic in-between to allow the way the Jaguar accesses the EEPROM to work. This means that any changes to the EEPROM data can actually be saved back to the memory card as they happen, which is rather neat.

Edited October 25, 2019 by SainT

[grimm]

Thanks for the update saint, im gwtting extited to be able to order this from you in hopefully the near future, as when you are ready to take orders.

[UHATEIT]

This invention will be the greatest thing since sliced bread!

[leech]

I had to make sure I got my Jaguar set up with the best video output, so SCART to HDMI is what I'm rocking now! Now just need this so I don't have to swap cartridges / CDs all the time.

 

For what it's worth though, Space Ace still looks as if you connected a VHS up to a 55" TV.. not sure that can be fixed, but Rayman looked positively awesome!

[+xucaen]

can't wait to see this actually exist. while I do nto have a jaguar yet it is a console I am in search of. I found one, but it's 175 at the local store and I, unfortunately, don't have that right now. Hoping it will still be there for a little bit, maybe can find some money. lol

Mine cost $250 3 years ago. If it works buy it.

[SoundGammon]

This invention will be the greatest thing since sliced bread!

Or is it canned peaches?

[leech]

Mine cost $250 3 years ago. If it works buy it.

I managed to get mine after they first went on sale from 250 to 150, and the JagCD I think had only just come out, and I think it was another 150?

 

As I was typing this, I realized I could just look at the boxes!

 

So it was 159.99 for the Mega-power maximum value! And 149.95 for the JagCD

Edited November 30, 2017 by leech

[Krip316]

This invention will be the greatest thing since sliced bread!

No, since his Lynx multicart.[emoji6]

[UHATEIT]

No, since his Lynx multicart.[emoji6]

I was going to say that other multicart haha dammit beat me to it!

[UHATEIT]

I managed to get mine after they first went on sale from 250 to 150, and the JagCD I think had only just come out, and I think it was another 150?

 

As I was typing this, I realized I could just look at the boxes!

20171130_095708.jpg

20171130_095728.jpg

 

So it was 159.99 for the Mega-power maximum value! And 149.95 for the JagCD

Resell that jag CD to me for $149.95

[Hastor]

For what it's worth though, Space Ace still looks as if you connected a VHS up to a 55" TV.. not sure that can be fixed, but Rayman looked positively awesome!

That's cause Rayman is using pixel based sprite graphics and Space Ace is encoded video made to fit on a CD and get played by older hardware. The fix to that is to pick up Space Ace on Blu-ray ray and play it on something that can change scenes without pausing. Playing it on a PS3 with the D-pad, which acts as a Blu Ray remote, is perfect. I doubt the Jag could process video with much more detail than is currently present. I also don't see anyone taking the time to improve it since there's a million better versions out there already.

[DEATH]

 

No, just been working off the standard cycle timing all commercial games use. I'm not sure if I'll look into faster ROM access... it's already very tight on the SDRAM cycle access.

 

Standard cycle timing all commercial games use ? You mean 10 cycles ? this is the slowest access time for ROM in Jaguar...

​do you think your jaguar SD card will be able to use less like 8, 6 or 5 cycles ?

[SainT]

 

Standard cycle timing all commercial games use ? You mean 10 cycles ? this is the slowest access time for ROM in Jaguar...

​do you think your jaguar SD card will be able to use less like 8, 6 or 5 cycles ?

 

Yep, 10 cycle. I have no idea as yet if I can get it going any quicker -- as I say the cycle timing for the SDRAM with refresh etc are quite tight. And to be honest, my goal is to run all commercial titles 100%, if I can get it doing more, great, but it's not a massive concern / priority at the moment.

[Pink]

Explain like i'm 5. I don't know much about these SD card multicarts I literally just stumbled upon this thread. I found my Jaguar in my closet earlier today and I have a renewed interest in it.

 

I saw in the Lynx SD Card thread a 1 GB sd card was enough to fit every Lynx game on it, so my question is how do we go about putting the games on it once were able to buy these SD carts after they're made available? Do they come preloaded with every game? Do you need to own the physical game you want to put on the SD Card? Or is there a site where we can download and load them onto the SD card? How hard (or simple) is it to download and load games on it?

 

I apologize in advance if my question is silly, but I have no experience with roms or hacks or downloading them or anything. I've ALWAYS been someone that plays the original console (not one of those "Clone" consoles like the Retro Duo or Retron 5 or whatever) with the cartridge. Only "experience" I have with roms is playing a few NES games on our computer with a keyboard in the late 90s on a Windows 98 computer when my older sister figured out how to download them herself and get them running. Surely on a forum about Atari, i'm hopefully not the only emulator/rom/hack virgin that's completely oblivious/naive as to how they work or how you go about getting them.

Edited December 1, 2017 by Pink

[SainT]

On 12/1/2017 at 11:43 AM, Pink said:

Explain like i'm 5. I don't know much about these SD card multicarts I literally just stumbled upon this thread. I found my Jaguar in my closet earlier today and I have a renewed interest in it.

 

I saw in the Lynx SD Card thread a 1 GB sd card was enough to fit every Lynx game on it, so my question is how do we go about putting the games on it once were able to buy these SD carts after they're made available? Do they come preloaded with every game? Do you need to own the physical game you want to put on the SD Card? Or is there a site where we can download and load them onto the SD card? How hard (or simple) is it to download and load games on it?

 

I apologize in advance if my question is silly, but I have no experience with roms or hacks or downloading them or anything. I've ALWAYS been someone that plays the original console (not one of those "Clone" consoles like the Retro Duo or Retron 5 or whatever) with the cartridge. Only "experience" I have with roms is playing a few NES games on our computer with a keyboard in the late 90s on a Windows 98 computer when my older sister figured out how to download them herself and get them running. Surely on a forum about Atari, i'm hopefully not the only emulator/rom/hack virgin that's completely oblivious/naive as to how they work or how you go about getting them.

 

It wont come with games, no. You get your game ROM images from somewhere, copy them onto a memory card, insert the memory card into the Jag cart, insert the Jag cart into the Jaguar, then turn it on. Select the game from the menu. Play it.

 

if you can copy stuff onto an memory card and otherwise have the dexterity to use the Jaguar, you can use it.

Edited October 25, 2019 by SainT

[Pink]

 

It wont come with games, no. You get your game ROM images from somewhere (ahem), copy them onto an SD card, insert the SD card into the JagSD, insert the JagSD into the Jaguar, then turn it on. Select the game from the menu. Play it.

 

if you can copy stuff onto an SD card and otherwise have the dexterity to use the Jaguar, you can use it.

Okay, awesome! I'm now extremely excited for this! Looks like I chose the perfect time to randomly get interested in my old Jaguar again! Was interested in obtaining more Jaguar games but yeah..... hard to find and when you find them they're not affordable. Retro games across the board have skyrocketed over the past couple years, doesn't help that 90s nostalgia is at an all time high and has become extremely trendy and popular over the past year or two.

Edited December 1, 2017 by Pink

[jjost]

Just a quick update, it's been a bit quiet for a while from me. Lots of things on at the moment, just never seems to be enough time in the day! Hence it's gone midnight again. Gah.

 

I've been working hard on the EEPROM save game support, and it's getting close to working. I've had to implement what I'd describe as an EEPROM to SPI bridge in the custom chip. It basically converts the data fed into the EEPROM bus into a series of bytes which are transferred over SPI to the microcontroller. Annoyingly the EEPROM is microwire, which has a variable length bit stream, whereas SPI is fixed. So it's difficult to read the EEPROM bus directly from the microcontroller (at least the one I am using), so hence I opted for the bridged approach.

 

I've finally just got a write packet being received correctly at the microcontroller, being sent from the Jaguar over the microwire EEPROM bus. Next is decoding the EEPROM packets as they come in and sending back suitable data for read commands and storing write data. As usual it's been amazingly time consuming to get it all working... there's something magical about developing hardware. It seems even seemingly simple tasks can often be a pig to get working seamlessly.

 

The concept here is that the microcontroller is basically acting as the EEPROM with a bit of magic in-between to allow the way the Jaguar accesses the EEPROM to work. This means that any changes to the EEPROM data can actually be saved back to the SD card as they happen, which is rather neat.

 

SainT, Sounds like fun! If you ever want some help I would be glad to donate time to this effort, no strings attached! Could help on VHDL/Verilog coding or sim/verification for the custom chip/FPGA or also donate some C coding effort on some modules or functions. Have fought with SPI bridge designs in past designs of my own. If you are like me you wont ask for (or want or take) help but I just think this project/product is great and will certainly buy it when ready! Was hoping for Christmas when I have time to actually play the Jag! Thank you.

[dilinger]

Hi,

Feel free to correct me if I'm wrong, but a SD card version for developer / programming was mentioned much earlier. Does it is still the case?

Thanks,

[SainT]

Hi,

Feel free to correct me if I'm wrong, but a SD card version for developer / programming was mentioned much earlier. Does it is still the case?

Thanks,

 

Did I mention I might do one? I lose track, I did think about it. I'm not, though. However I've heard the skunkboard is available again if you just want something to do some programming on.

[SainT]

 

SainT, Sounds like fun! If you ever want some help I would be glad to donate time to this effort, no strings attached! Could help on VHDL/Verilog coding or sim/verification for the custom chip/FPGA or also donate some C coding effort on some modules or functions. Have fought with SPI bridge designs in past designs of my own. If you are like me you wont ask for (or want or take) help but I just think this project/product is great and will certainly buy it when ready! Was hoping for Christmas when I have time to actually play the Jag! Thank you.

 

I'll give you a shout if I get stuck on anything, always happy to bounce ideas around! I've got the bridge part working, I'm just sorting out reliability issues with the SPI transfer from the ASIC to the micro at the moment. Its taking days to track down and has been a multitude of issues! I've had fun issues like streamlining the SPI master controller with a FIFO so I can speed up the continuous transfer rate over SPI has shown the micrcontroller cant actually handle the SPI DMA as quick as I thought! I've added handshaking everywhere to rule out race conditions, but I'm still getting odd hangs where the SPI DMA isn't completing where it should, so there's still something left to find.

[jjost]

 

I'll give you a shout if I get stuck on anything, always happy to bounce ideas around! I've got the bridge part working, I'm just sorting out reliability issues with the SPI transfer from the ASIC to the micro at the moment. Its taking days to track down and has been a multitude of issues! I've had fun issues like streamlining the SPI master controller with a FIFO so I can speed up the continuous transfer rate over SPI has shown the micrcontroller cant actually handle the SPI DMA as quick as I thought! I've added handshaking everywhere to rule out race conditions, but I'm still getting odd hangs where the SPI DMA isn't completing where it should, so there's still something left to find.

 

Hi SainT. Lots of holes (in fact one big void!) in my knowledge of your board. I don't know what micro you are using or who is the master in your DMA transaction, so, with all that said, here are some comments based on my experience. Likely 94.5% wont even be applicable and/or you have already tried it

 

- Min time violations between SPI CS assertions (likely only if DMAing data into the micro since you likely control your FPGA SPI code tightly and have total visibility there)

- Assumption is that all general timing is correct (setup, hold, clock polarities), CS assertion to first clock, last clock to CS deassertion

- DMA buffer descriptor gets corrupted somehow (this is always fun!) so controller does not know when to complete or goes off into the weeds

- Try just slowing the clock to see if it acts differently, might give a clue

- If worse comes to worse, and you are mastering the DMA from the proc, try reversing it if your proc allows being a SPI slave so that you have the most control through your custom logic in the FPGA. This is painful given it does require more work to get there given the time you have already spent on trying to make it work in the other direction and is a last resort or perhaps if there is performance merit in switching it around might make sense.

 

Again these are thoughts based on what has gone wrong on the past in my experience. Hope it helps

[DEATH]

 

However I've heard the skunkboard is available again if you just want something to do some programming on.

 

Realy ? Where ?

[SainT]

 

Hi SainT. Lots of holes (in fact one big void!) in my knowledge of your board. I don't know what micro you are using or who is the master in your DMA transaction, so, with all that said, here are some comments based on my experience. Likely 94.5% wont even be applicable and/or you have already tried it

 

- Min time violations between SPI CS assertions (likely only if DMAing data into the micro since you likely control your FPGA SPI code tightly and have total visibility there)

- Assumption is that all general timing is correct (setup, hold, clock polarities), CS assertion to first clock, last clock to CS deassertion

- DMA buffer descriptor gets corrupted somehow (this is always fun!) so controller does not know when to complete or goes off into the weeds

- Try just slowing the clock to see if it acts differently, might give a clue

- If worse comes to worse, and you are mastering the DMA from the proc, try reversing it if your proc allows being a SPI slave so that you have the most control through your custom logic in the FPGA. This is painful given it does require more work to get there given the time you have already spent on trying to make it work in the other direction and is a last resort or perhaps if there is performance merit in switching it around might make sense.

 

Again these are thoughts based on what has gone wrong on the past in my experience. Hope it helps

 

All those thoughts were things that had run through my mind also, all very reasonable and good things to check!

 

As usual, with stupid hard to find bugs, it was a multitude of issues. First was a bug in the Jaguar code sending the SPI data, it was transferring one word too little, which is why one test case was giving different results to another. Next, good old physical contact issues! As I've been screwing with the SPI code (and breaking it) I've had to reprogram the cart by removing it from the Jaguar and programming from my custom USB Jaguar cart programmer. This caused the contacts to get dirty and give me dodgy connections and corrupted data. So it wasn't in fact the SPI data getting corrupted at this point, it was just a reasonable (but wrong) assumption! And finally, I'm not sure why, but the SDRAM controller was giving glitchy results, again resulting in corrupted write data, so I managed to up the clock frequency again (had to drop it due to timing issues elsewhere before, but I've sorted those) and sorted out the LFSR timers for the refresh and we're (finally!) back in business.

 

Well, at least until I try and add more functionality again! At least I'm now just adding back in things rather than re-writing loads of blocks at once. Eurgh! Still, all good.

[Lynxpro]

LOL, such thin skin, and I'm a sausage casing.

 

I find the decision to go with a 3D printed shell extremely disappointing- and it kills production, even if SainT buys multiple machines or whatever he's going to do to speed that end up, it's still going to be a bottleneck. And the resolution for consumer grade machines has yet to come close to be aesthetically pleasing. I respect the direction as an economical one but for a finished product... again, disappointing.

 

And yeah, I said it. There is going to be no competition to sway the design another way- that's the truth isn't it? If the Jaguar was a more popular console we'd have seen an Everdrive version by now, though I will give the guy credit and say I have more confidence in SainT's electrical design properly shifting 3.3v out of 5v versus what Krikkz has come up with. Unarguably it will be a safe device to use on the Jaguar.

 

 

 

1. Well, maybe SainT could just make the STL file public on Thingiverse and then transfer the burden of producing the cartridge case on us. A lot of public libraries have 3D Printers that the public can use, at least here in CA. And then SainT wouldn't have to worry about production time for those cases and just ship out the boards to all of us.

 

2. Krizz/Krikkz/Jizz doesn't do jack outside of Japanese consoles. Based upon your assertion, there should be 2600 and 7800 EverDrives from him and there aren't. The 2600 sold 30 million+ consoles. The 7800 sold 4 million in North America, not counting Europe. I even emailed him when Concerto started getting bogged down and asked him to design a 7800 EverDrive. Not a peep was heard of from that.

[Lynxpro]

 

 

 

And don't forget the original Krikzz carts came with no shells at all, you had to butcher your old games if you wanted one. You can still do this if you wish, up to you.

 

 

 

 

Sadly, nobody wants to use non-Sega cartridge cases either for the Mega EverDrive boards. Man, if there was a place to trade in EA or Accolade cartridge cases in exchange for something like AtariAge's trade-in credits, I'd be a hundredaire by now! C'mon, Albert, expand into the Sega Genesis homebrew market...after all, it could've been the Atari Genesis.