In doing research for a future review, I noticed that a bunch of the most desirable games use the SA-1 chip. Now, if I'm not mistaken, you cannot just take it out of a donor cart, as part of the actual game DATA itself is on the chip. But, I also heard rumblings of a possible emulation of the chip. Those being said, will there be support in the future or is it a no-go?
No. Never. New very expensive hardware would be required, combined with alot time and development to mimic the SA-1's operation. All this for only a handful of "most desirable games". This makes no sense to do. And no, part of the game's data is not on the SA-1 chip itself.
I meant most desirable as in "most expensive and hard to find", like Super Mario RPG, Kirby's Dream Land 3, etc. I've always read that 1/4 of the game data is on the SA-1 chip itself for copy protection. Well, you learn something new every day....
There are a whole 3 games that I personally find desirable that use the SA-1 chip out of the entire list on Wikipedia. Some games are worth buying. The other 99% aren't usually worth pirating and you can play them just fine with an Everdrive.
SA-1 and Super FX aren't just chips you can drop in like DSP chips, at least that's what Igor has told me. Most likely these would need to be emulated and this would add a lot on to the cost. I think someone is trying this as a project. its called SD2SNES I believe, but I don't think they have really been that successful, at least not with the more desirable chips like the SA-1 and Super FX. This is not to say its impossible, but right now the even if it was done the cost of the cart would be quite a bit.
I ask that because to a new customer, that's first and foremost on their minds. It's best to drop that early on, more to say, "yeah, these few don't work, but look at all of these other awesome games that DO work! It's still worth it." That's my aim with this one. To quell some fears and add a little more insight. I look at past videos for reference and I didn't see very many for this one. So, there only a couple of demos here and there, but nothing in depth. So, it's going to be a tutorial/demonstration/commercial this time. It will most likely be as long as the last because I found a whole mess of games to show. Some of which take the SNES to the limit. I know I'm rambling on, but when I get sucked into a project, I cannot help it lol
I'd swear somewhere along the line such questions were answered but I can't for the life of me find anything that has it spelled out. You could require someone read the manual before being able to post in this sub forum but someone will always be asking something that has already been answered. From what I recall to add SA-1 in (or Cx-4 for that matter, et al) the maskrom is accessed through the chip (to some extent) which would require that the Everdrive be designed in a similar manner. Not 100% sure about that or how it works as SNES hardware isn't exactly my forte. Some info here: http://www.nesdev.com/bbs/viewtopic.php?p=80068&sid=6bd99b9d17d7596999c21b070204aca3 If an Everdrive could be made that supported every chip under the sun it'd probably be cheaper to buy a car.
"DSP games" are implemented like regular games, they just have some memory decoded to the DSP chip, little different than decoding SRAM, basically you can drop it in since everything is in parallel on the data bus. SA-1 and Super FX games don't work like this, the chips arbitrate the CPU's access to the ROM in order for the ROM to be multiplexed between the CPU and the special chip. The ROM is hidden behind the chip. Because the Everdrive wasn't designed to switch the ROM between the CPU and SA-1 (or Super FX), an adapter would have to be produced using not only original parts but new logic and connectors. The adapter would be more expensive than the Everdrive, it could have timing complications and it would probably require updates to the core Everdrive. The sd2snes synthesizes the chips in the cart's programmable logic (which is wired such that it can multiplex the ROM -- which is implemented in fast RAM). The Everdrive isn't wired to do this, and if it were it doesn't have a fraction of the resources to implement the DSP much less SA-1. The SA-1 exceeds the complexity of the SNES' CPU or approximately 1/3 of the SNES logic in entirety. Plus the work itself is significantly more advanced than designing a flash cart, few people are up for that.
I think the only way you're likely to see the SA-1 on a Flash Cart or Copier of some kind would be if someone essentially took the SA-1 out of a existing cartridge and put it into their hardware design with essentially a big switch/disconnect so that it could be connected like the original cart when needed. But the cost of such a thing wouldn't be cheap. I forget how many pins the SA-1 is but it's a high number. You'd have the cost of getting the chips plus the labor of successfully transplanting them from one thing to another. The cost of such a device would be very expensive, far more than the cost of buying the few SA-1 games you want to play.
SA1, SDD1, etc. Those are some pretty powerful ASICs. You are talking about designing a complete full general purpose 16 bit 10 Mhz CPU made entirely of NOR or NAND gates in a FPGA. That's far more involved than just some basic address decoding and mapping logic in the CPLD it's using now. The FPGA alone that would be required to implement the more advanced chips would likely cost as much as a whole Everdrive. Pointless just for 2-3 games you can buy on Ebay for $25 each.
