View Full Version : FPGA solution for special chips on SNES?
Visker
12-17-2010, 08:03 AM
Im about to order the everdrive MD, since it has nearly perfect compatibility with MD games. Virtua racing ill play the superior 32x version :)
Now i read a couple of discussions about the everdrive and other romcards about the lacking special chips, some suggested having a socket to solder a real chip into, which wouldnt be so bad idea if it was only one special chip, but there are nearly a dozen for the SNES, and sadly for me personally some of the best games like super mario world 2 depend on those special chips.
Recently i played around with the DSTWO flashcard for the NDS. IT uses a FPGA to emulate all of the SNES instead of the internal CPU, and does it quite smoothly.
So my suggestion would be, why not try to implement an FPGA onto the PCB?
The DSTWO uses a Actel ProAsic3, a very small/cheap and lowpower FPGA chip pictured in the link below
http://gbatemp.net/news/09_supercardds2_review_pcb_front.jpg
Specificly it uses the A3P125 version, found in the datasheet of Actel below
http://www.actel.com/products/pa3/
They name the unitprice as low as $0.99, assume that the one needed to emulate everything perfectly is $2 or $2.5 worst case scenario.
The sourcecode for all the special chips is available at (im sure a deal can be made with the developer )
http://www.zsnes.com/index.php?page=files
Of course this would still involve quite some work to get it running perfectly, but while i find $80 not quite justified for the limited compatibility, if you made this card with the FPGA with near 100% emulation i would put down $120 for it in a heartbeat. Also any other romcard manufacturer would be put out of business since it would not have any competition, again more profit!
I hope the idea is consider :)
KRIKzz
12-17-2010, 09:09 AM
1) why you thinking that A3P125 do snes emulation? 1024 macro cells it is too small for snes implementation, or even for spec chips only implementation. here need some like altera cyclon or eq and such class of chips price much more 2.5usd, 40usd min i gues .
2) C sources totally unusable for FPGA implementation, even as sample
3) i dont want to spend 400-500% more time for make just little more popular device, or even it will be not so popular device as current, because all want chips compatibility, but nobody want pay 2x or 3x price. who need costly device just for few good games? you easy can buy original games for few $ on ebay. so i think that spec chips implementation is irrational step
MottZilla
12-17-2010, 04:18 PM
FPGAs are not magic. Cloning the special chips would take a significant investment of time. Some chips are used in a good bunch of games while others are used in 1 or 2 games. Not at all worth the effort in cloning them on a FPGA.
As KRIKzz said, the original cartridges are not that expensive if you want to play those games. But the cost to add support for those games to EverDrive would probably equal or maybe surpass the cost of buying all the games you would want to play.
It would be awesome if you could play absolutely 100% of the SNES library on one flash cartridge or copier but that's very unlikely to happen and if it ever does it will cost probably much more than you are willing to pay.
Calpis
12-17-2010, 06:09 PM
To add to this, the FPGA used in DS adapters are not used for their FPGA abilities, they are used as quick-time-to-market ASIC. In order for a single FPGA to be reused across multiple special chips and core logic it would need even more external logic to bootsrap and reprogram the FPGA or the FPGA would have to be self-reconfiguring which is a very tricky process that few people in the entire industry dare to attempt (and I think there is often a $2K+ license for this feature on development environments). You, sir, are misguided about the technology (clearly there are more real life limitations on things than you realize), and are cheap :-P
Why is it that everyone thinks this stuff is easy to pull off???
StoneAgeGamer
12-18-2010, 01:36 AM
Like Igor said in the end this comes down to money. I am sure if he could sell 100,000 of these next year if it supported these chips it may be worth the investment to figure out a solution.
However, we are talking about a niche market of an already niche market item that has heavy competition from emulators and next gen virtual consoles. If doing this was easy RetroUSB, TotoTek, or Igor would have done it by now.
djelaba
12-21-2010, 05:05 AM
With the decapping of the dsp-1 (http://board.byuu.org/viewtopic.php?f=16&t=1249) (and the dump of the rom), can it be adapted to a pic ? Either by using the uPD77C25 emulator inside bsnes, or by reversing the rom using Overload's disassembler.
KRIKzz
12-21-2010, 06:03 AM
uPD77C25 capability unknown for me, but i think uPD77C25 can be replaced by some modern MCU
link83
12-21-2010, 08:13 AM
I didnt know the DSP-1B had been decapped and the ROM dumped :-0
I think DSP-1B support using an MCU would be fantastic, expecially since it is the most commonly used SNES special chip. Is this something you are already working on KRIKzz?
KRIKzz
12-21-2010, 12:33 PM
no, i not worked over it, to many time need. much more easy to use dsp from donnor cart. i not hacker and in revece engineering i also not a master. i can create some hardware only if i have specification. code repair from binary or some similar things is not for me.
rogerhanin2002
12-21-2010, 12:44 PM
I didnt know the DSP-1B had been decapped and the ROM dumped :-0
it seems to be very recent news. see this interesting article of the well know byuu. http://byuu.org/articles/decap
don't forget the link to the Dr decapitator's page http://decap.mameworld.info/
Bootay
12-21-2010, 02:49 PM
Like Igor said in the end this comes down to money. I am sure if he could sell 100,000 of these next year if it supported these chips it may be worth the investment to figure out a solution.
However, we are talking about a niche market of an already niche market item that has heavy competition from emulators and next gen virtual consoles. If doing this was easy RetroUSB, TotoTek, or Igor would have done it by now.
RetroUSB actually has implemented DSP1 but it is not possible to do more than one special chip on one cart. There is a total of 28 games I believe that use the other chips and out of that 28 there are like 3 good ones. So I chose to buy the Powerpak and the 3 good SuperFX games. This was before Krikzz made his SNES cart or I may have considered his just because of price. $135 is not a casual spend, but I personally feel it was worth it.
KRIKzz
12-21-2010, 04:57 PM
RetroUSB actually has implemented DSP1.
he not implement dsp on some custom hardware, he just used original chips from donnor carts. look here (http://www.img-teufel.de/uploads/front3c5cdd22jpg.jpg)
Greg2600
12-21-2010, 05:53 PM
Yes it was originally like $11 US to get the donor chip installed. Now it's included. RetroUSB's SNES cart has suffered a lot of problems with the CF Card scheme as well. I think he only recently fixed all of it, but it required sending it back to him for updates.
Bootay
12-21-2010, 07:37 PM
Yes it was originally like $11 US to get the donor chip installed. Now it's included. RetroUSB's SNES cart has suffered a lot of problems with the CF Card scheme as well. I think he only recently fixed all of it, but it required sending it back to him for updates.
Greg2600: What problems are you referring to? I have had my SNES Powerpak since the first week he offered it and never had any issues with anything.
Kirkzz: Ahh I was not aware that they were donors. Either way though it works quite well.
Alchy
12-21-2010, 08:21 PM
Greg2600: What problems are you referring to? I have had my SNES Powerpak since the first week he offered it and never had any issues with anything.Most people seem to be fine but there's also a lot of people who've had serious issues. Myself included - I've tried my PowerPak on three different Superfamicoms and it hasn't worked right on any of them. If I remember right, two give errors right at the start and won't load games, the other loads games but hangs almost immediately (at the developer logo or menu). If he's released new fixes I should probably check it out, but I've just about given up on the fucking thing, to be honest.
Bootay
12-21-2010, 11:12 PM
Most people seem to be fine but there's also a lot of people who've had serious issues. Myself included - I've tried my PowerPak on three different Superfamicoms and it hasn't worked right on any of them. If I remember right, two give errors right at the start and won't load games, the other loads games but hangs almost immediately (at the developer logo or menu). If he's released new fixes I should probably check it out, but I've just about given up on the fucking thing, to be honest.
Ahhh...I use a US SNES..maybe that's the difference. Who know. I was not aware of any issues since mine has always been well worth the $135. But I can see how issues could occur on different hardware types. I wish you good luck on it Alchy.
Wolfeman
12-27-2010, 08:48 PM
the solution is easy, use a T-connector like Tototek, you pop in a cart with the chip you need, the flash cart checks the cart on the t-connector and launches the game.
maybe the tototek t-connector will work already?
BM-Viper
12-27-2010, 09:37 PM
I believe someone has stated it already does. Keep in mind though, the T-connector will only help with DSP1 games.. not c4 or superfx or any of the other chips.
Wolfeman
12-27-2010, 10:23 PM
hmm, I thought the tototek t-connector worked with any chip as long as you had game with the right chip inserted. here is the link:
http://www.tototek.com/store/index.php?main_page=product_info&cPath=1_8_11&products_id=40
but honestly I can not make it out form the engrish description of it so you're probably right if it has already been discussed.
the retrousb snes cart already has dsp1 game support built in so it would seem THAT cart has a one-up on the krikzz snes cart.
BM-Viper
12-28-2010, 12:55 AM
The english description only mentions super mario kart (DSP1 game) and no others....
Also, i believe KRIKzz is putting out a revision of the SuperEverDrive at some point with an area to solder in a DSP1 chip... which is what the SNES PowerPak does.
Bootay
12-28-2010, 08:35 AM
The english description only mentions super mario kart (DSP1 game) and no others....
Also, i believe KRIKzz is putting out a revision of the SuperEverDrive at some point with an area to solder in a DSP1 chip... which is what the SNES PowerPak does.
Powerpak works with all DSP1 games. FYI.
Greg2600
12-28-2010, 10:30 AM
The english description only mentions super mario kart (DSP1 game) and no others....
Also, i believe KRIKzz is putting out a revision of the SuperEverDrive at some point with an area to solder in a DSP1 chip... which is what the SNES PowerPak does.
Sure about that?
PS: Tototek plug-in slot only works for DSP-1, because DSP-1 is the only chip that is capable of being accessed in that fashion. The other chips simply won't work that way.
BM-Viper
12-28-2010, 10:44 AM
Powerpak works with all DSP1 games. FYI.
I'm aware. It has a DSP chip out of a donor cart soldered on to the board.
As far as the Super EverDrive supporting DSP-1 games, I'm pretty sure I recall there being talk about a revision with a dsp-1 socket coming out at some point. The best person to talk to on that would be KRIKzz.
Greg2600
12-28-2010, 01:52 PM
You're correct, as recent as about 2 months ago, Krikzz said a future PCB would have a slot for a DSP-1 chip. No telling when that will be.
KRIKzz
12-28-2010, 02:36 PM
carts with place for dsp will be available in first months of year 2011
link83
12-28-2010, 03:52 PM
carts with place for dsp will be available in first months of year 2011
Great to hear :-) I have been looking forward to a DSP-1 compatible Super Everdrive.
Does that mean you will be selling four different versions of the Super Everdrive, using two different PCB's?
Super Everdrive
Super Everdrive +USB
Super Everdrive DSP-1 compatible
Super Everdrive DSP-1 compatible +USB
Its not much of a problem, but I guess one thing to keep in mind is that a DSP-1 compatible Super Everdrive will only fit in a game case that originally used a special chip (DSP-1, Super FX etc) As these cases have side grooves for the extra pins, and other game cases wont have these grooves so would need to be cut/modified for the PCB to fit.<EDIT> Please ignore the previous paragraph, I was mistaken - DSP-1 games dont use the extra side pins.
KRIKzz
12-28-2010, 06:08 PM
new pcb will be have same form factor as current version. shels for dsp games same as standard shell
ceramiclion
12-28-2010, 07:39 PM
Aww man and I havent even received my Super Everdrive yet. Oh well...:(
Bootay
12-28-2010, 07:54 PM
Good news Kirkzz! The Powerpak is great but yours is much more affordable. So I salute you on that.
link83
12-29-2010, 12:46 PM
new pcb will be have same form factor as current version. shels for dsp games same as standard shell
My mistake :redface: for some reason I thought DSP-1 games used the extra side pins like the Super FX etc.
Sisee
01-17-2011, 01:56 PM
new pcb will be have same form factor as current version. shels for dsp games same as standard shell
Any more news on that?
I notice that the current pics of the board have several blank spaces with soldering points. Is that where the chip will go?
Also, have we got a more accurate ETA on the new boards?
I want to order a Super EverDrive, but if there's to be a revision with DSP-1, I think I'd be tempted to wait. That is as long as it's definitely coming. If not, I'll just get the regular version.
Teancum
02-09-2011, 02:08 AM
I think someone mentioned before that it should be possible to use the tototek connector. Here's confirmation
http://www.youtube.com/watch?v=wJfzQetP7HA&feature=player_embedded#
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