phoenixdownita Posted July 9, 2017 Share Posted July 9, 2017 I am not sure it's been asked but this Jag SD baby is been built with SRAM/PSRAM/CellularRAM right? Not flash I hope. I have a NeoSD and it's on the slow side of loading, granted the Jag games are not long at all in comparison (128MB vs 4MB), but I did see a video about your NGPC solution and the loading time are a little long imho (not bashing your product just stating my opinion here). Can we hope loading a 4MBytes game on the Jag would be accomplished in say under 1minute? Quote Link to comment Share on other sites More sharing options...
+Sauron Posted July 9, 2017 Share Posted July 9, 2017 Can we hope loading a 4MBytes game on the Jag would be accomplished in say under 1minute? I think the bigger trick is loading a 4MB game into 2MB of RAM... Quote Link to comment Share on other sites More sharing options...
phoenixdownita Posted July 9, 2017 Share Posted July 9, 2017 I think the bigger trick is loading a 4MB game into 2MB of RAM... I venture it is mapped into the 6MB cart space, so I am not sure why the 2MB comment. There's 15 originals that are 4MB and all of the skunk-only ST ports from CJ ... Quote Link to comment Share on other sites More sharing options...
SainT Posted July 9, 2017 Author Share Posted July 9, 2017 (edited) I am not sure it's been asked but this Jag SD baby is been built with SRAM/PSRAM/CellularRAM right? Not flash I hope. I have a NeoSD and it's on the slow side of loading, granted the Jag games are not long at all in comparison (128MB vs 4MB), but I did see a video about your NGPC solution and the loading time are a little long imho (not bashing your product just stating my opinion here). Can we hope loading a 4MBytes game on the Jag would be accomplished in say under 1minute? Using flash is a limitation of the NGP, and sadly flash write speeds of these flash chips are pretty slow. Compare the speed with the NeoGeo cart (or other flash based solutions) and you'll see similar flash times. The Jag will not being using flash, no. Loading a 4MB game should take seconds rather than minutes. Edited July 9, 2017 by SainT 6 Quote Link to comment Share on other sites More sharing options...
phoenixdownita Posted July 9, 2017 Share Posted July 9, 2017 Using flash is a limitation of the NGP, and sadly flash write speeds of these flash chips are pretty slow. Compare the speed with the NeoGeo cart (or other flash based solutions) and you'll see similar flash times. The Jag will not being using flash, no. Loading a 4MB game should take seconds rather than minutes. As soon as you abandon the design to use only one flash chip then other alternatives crop up that can speed up the process, but that is another story altogether .... glad it'll be FAST!!!! 1 Quote Link to comment Share on other sites More sharing options...
SainT Posted July 9, 2017 Author Share Posted July 9, 2017 (edited) As soon as you abandon the design to use only one flash chip then other alternatives crop up that can speed up the process, but that is another story altogether .... glad it'll be FAST!!!! Hmm, its possible to write to both flash chips at the same time, this is true. Thanks for the idea! This could potentially speed up flashing a by a good margin for any game over 512k (for the NeoGeo Pocket that is). Edited July 9, 2017 by SainT 5 Quote Link to comment Share on other sites More sharing options...
phoenixdownita Posted July 10, 2017 Share Posted July 10, 2017 Hmm, its possible to write to both flash chips at the same time, this is true. Thanks for the idea! This could potentially speed up flashing a by a good margin for any game over 512k (for the NeoGeo Pocket that is). I am sure your customers would be more than delighted if you could offer a ~1.5x-2x speed up improvement with a FW/bitstream update (depending on how you went about flashing), at least you can try to see how far you can get with it. An alternative HW design is to have multiple "flash banks" each with a separate databus (controlled by the FPGA) and you write to all the banks in parallel but when you read you use one/more of the address bits to select the bank (hence the FPGA controlled databus) to multiplex on the console databus ... it requires more pins on the FPGA (one databus worth per bank), and obviously flashing in parallel is not "trivial" especially dealing with failure modes but it is doable. If the banks are programmed interleaved even small games will speed up and you can use the lsbs to select the bank at read time, first bank gets first byte/word, second bank gets second etc.... this can be done literally by byte/word if you can pump data at the right time or using blockRAM in the FPGA to prepare the 1st/3rd/5th/... for the first chip and the 2nd/4th/6th/.... for the second and so on, you can see you can have more than 2 parallel banks, say 4 or 8 but then the I/O required on the FPGA is too high and the number of chips/routing takes too much space .... unless of course it's a PCB as big as the NG [i do not know what the NeoSD does so ....]). 1 Quote Link to comment Share on other sites More sharing options...
SainT Posted July 14, 2017 Author Share Posted July 14, 2017 (edited) Quick update on the Jag, I've finally finished the first pass on the cart and programmer PCB's and they've been sent to the fab house. So in about 3-4 weeks I'll actually start doing some physical messing with the cart. The first step will be the worlds worst Jag flash cart as I get the 128K boot flash working, then I'll add the CPLD and RAM and get that running so we've got 16MB of RAM on there to play with, then get the micro working to actually get stuff from the memory card. Sounds easy written like that, lol, but I'm sure there will be plenty of pain along the way. Edited October 25, 2019 by SainT 18 Quote Link to comment Share on other sites More sharing options...
UHATEIT Posted July 14, 2017 Share Posted July 14, 2017 Good luck dude! We are all excited for this unit once you've got it working! I wish I knew how to do this kind of stuff Quote Link to comment Share on other sites More sharing options...
soob Posted July 15, 2017 Share Posted July 15, 2017 I can't wait for this! Just sold my entire Jag collection in anticipation I love using original hardware but I'm not a fan of having shelves stacked with games. This age of flashcarts we're living in blows my tiny mind. 2 Quote Link to comment Share on other sites More sharing options...
Atari Nut Posted July 15, 2017 Share Posted July 15, 2017 I'm looking forward to this. Quote Link to comment Share on other sites More sharing options...
Hesterfu Posted July 19, 2017 Share Posted July 19, 2017 Im in!! i loved the NGPSD! Quote Link to comment Share on other sites More sharing options...
Karyyk Posted July 20, 2017 Share Posted July 20, 2017 I'm really looking forward to this. Definitely in for this. Quote Link to comment Share on other sites More sharing options...
phoenixdownita Posted July 20, 2017 Share Posted July 20, 2017 I can't wait for this! Just sold my entire Jag collection in anticipation I love using original hardware but I'm not a fan of having shelves stacked with games. This age of flashcarts we're living in blows my tiny mind. I thought a full Jag set sits in not that much space (but I can see wanting to reclaim it): (Not my collection) Quote Link to comment Share on other sites More sharing options...
JagChris Posted July 20, 2017 Share Posted July 20, 2017 I can't wait for this! Just sold my entire Jag collection in anticipation Dude that sucks. He just cancelled the project citing part supplier difficulty 1 Quote Link to comment Share on other sites More sharing options...
JagChris Posted July 20, 2017 Share Posted July 20, 2017 No no I kid. Quote Link to comment Share on other sites More sharing options...
UHATEIT Posted July 20, 2017 Share Posted July 20, 2017 There must be a grip of people selling off their collections. I've seen a bunch of eBay auctions with the same seller selling like 20+ games each. What will happen to the collectors market of these? The Jag games have exploded in price it seems as of late. Quote Link to comment Share on other sites More sharing options...
Stage_1_Boss Posted July 20, 2017 Share Posted July 20, 2017 There must be a grip of people selling off their collections. I've seen a bunch of eBay auctions with the same seller selling like 20+ games each. What will happen to the collectors market of these? The Jag games have exploded in price it seems as of late. As a collector that enjoys getting physical Jaguar games, I don't mind other people shuffling their collections out, as long as they're still having fun and hopefully still interested in the Jaguar community. = ) 2 Quote Link to comment Share on other sites More sharing options...
UHATEIT Posted July 20, 2017 Share Posted July 20, 2017 As a collector that enjoys getting physical Jaguar games, I don't mind other people shuffling their collections out, as long as they're still having fun and hopefully still interested in the Jaguar community. = ) I've started collecting at the time the SD is in process and people are dumping their carts. I wish the prices were as they were a while ago. I'm an original Jag owner since 1995 and have all my original stuff and have been collecting again as of recently. It's nice to see a bunch listed on eBay but the prices are 2 Quote Link to comment Share on other sites More sharing options...
DoTheMath Posted July 20, 2017 Share Posted July 20, 2017 Hi everyone! Made an account just for this. I don't have my original Jag anymore but i rebought one and yes, games are getting expensive. Managed to buy some mint ones but others like Rayman, i'll have to pass There is also the Jag-CD issue that could be resolved by this catridge. I'd love to replay Myst on the Jag this time. Iron soldier 2 and Battlemorph look amazing too... Quote Link to comment Share on other sites More sharing options...
SainT Posted July 20, 2017 Author Share Posted July 20, 2017 Getting quite excited now the first PCB's are in production. I've just been looking at the fact you could add an additional 2MB of internal RAM to the Jag if you wanted.... the additional lines are on TOM (RAS1/CAS1). With some 5v SRAM and some logic to convert the RAS/CAS address into a linear address it could be done with available / in production components (nothing worse than designing something using obsolete and hard to find chips). There is very little point to doing this, of course, other than the fact I keep thinking about a Jaguar based computer once the JagSD is out. As there's no reason not to build EMUTOS to run on it and have GEM running on the Jag.... potentially with 4MB internal RAM and 16MB external RAM. Again.... completely pointless. But I can't help finding it appealing. 8 Quote Link to comment Share on other sites More sharing options...
DoTheMath Posted July 20, 2017 Share Posted July 20, 2017 Again.... completely pointless. But I can't help finding it appealing. I'm not literate on the subject but couldn't that be useful to homebrew developement somehow? Maybe for debugging purposes? Quote Link to comment Share on other sites More sharing options...
SainT Posted July 20, 2017 Author Share Posted July 20, 2017 I'm not literate on the subject but couldn't that be useful to homebrew developement somehow? Maybe for debugging purposes? It would only be useful for homebrew / new software written to take advantage, yep. In theory it could help a lot having an additional 2MB of RAM on the main 64-bit bus as the existing 2MB is limiting after video memory etc... is taken out. Quote Link to comment Share on other sites More sharing options...
DoTheMath Posted July 20, 2017 Share Posted July 20, 2017 Time to go all in and make new retrocompatible hardware. Quote Link to comment Share on other sites More sharing options...
JagChris Posted July 20, 2017 Share Posted July 20, 2017 It would only be useful for homebrew / new software written to take advantage, yep. In theory it could help a lot having an additional 2MB of RAM on the main 64-bit bus as the existing 2MB is limiting after video memory etc... is taken out. Do it. DOO ITT! Thanks. Quote Link to comment Share on other sites More sharing options...
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