androvsky

I can't prove when the interview was actually taken, but there's apparently a new interview with Polymega up: http://www.nintendolife.com/news/2018/09/exclusive_polymega_creator_playmaji_on_fpga_sega_saturn_and_dealing_with_healthy_scepticism

Correct me if I'm wrong (please, I'm considering using something similar in a project), but RetroAchievements requires Retroarch, which is GPL v3, on non-Windows platforms. Which means if they use it they have to leave the hardware open so that end-users can load their own customized copy of Retroarch onto the system. Now that shouldn't be a problem normally, but if they're locking down the system because they're serious about enforcing the encrypted ROM backups and store downloads, then that's going to be incompatible with GPL v3. Otherwise I totally get where you're coming from, I've seen a ton of people and companies confuse GPL with non-commercial usage. But I get the feeling in this case they really can't, unless they're willing to back down on enforcing encrypted ROMs. I'm ignoring the liklihood that it'll get hacked anyway, that doesn't make it GPL v3 compliant afaik. I'd guess it's one of the reasons they're going with Mednafen, since it tends (depending on the core iirc) to be GPL v2 which is more permissive on closed systems.

I wonder if the latter number is what they're quoting and the board is really 6 or 7 layers.

They kinda can't do that. The GPL3 license RetroArch uses is very strict in that everyone that receives the software has the same rights to the software. RA could ask for money for their project, but so could you or I, or Seedi. And by extension, anyone could give it away for free. Even if RA switched to a proprietary license, anyone could still use the last version that was GPL3 and the community could keep contributing to it (that's happened to many open-source projects). Granted, some of the emulation cores have different licenses, but most of them are GPL. The interesting thing about GPL3 is it has an anti-Tivoization clause that requires device manufacturers to allow end users to modify the GPL3 code that's on the system, which tends to make it very awkward to use for most larger device makers that like to lock down their systems. One thing RA could do is license a proprietary version of RA that doesn't have that restriction, but it'd require every RA contributor to allow it, and anyone could still use the GPL3 version for free. But there's been a few GPL projects that have taken that route as well.

I'm trying a multi-quote, have a funny feeling the formatting is going to be broken. You can't live your life assuming a court is going to randomly make a ruling that completely goes against existing law. At worst, there can be an appeal. If the SNES was designed using FPGAs originally, it's super easy to prove that any other implementations aren't derived works because there's no way the source code that was used to make the SNES ever became public. And if it was, it had to be in an old language form that's not used any more, and it probably wasn't meant to run efficiently so a modern implementation would be completely different anyway, almost by definition. Are you talking about the BIOS in the Connectix case? Sony lost that suit because the court ruled that the copy of the BIOS Connectix used internally to reverse engineer it was fine, since it was impossible to reverse engineer otherwise. The reason Sony owns the Connectix PS1 emulator is because they bought it from Connectix after losing the suit. They also hired the main programmer from Bleem! after Sony lost that suit as well. Both of which happened after the DMCA was enacted, btw. I know Hollywood and the DMCA has people worried about copyright overreach by corporations, but there are still rights people have, and reverse engineering is one of them.

Is there a quote about letting them bypass the system bios with hybrid emulation? I know they've said they've got the bios problem solved somehow, but I don't recall it being in relation to the hybrid emulation, as that doesn't make any sense especially for the CD systems. In short, it makes perfect sense that it bypasses the virtual mappers of the emulator (but definitely not the bios for CD systems). The game the emulator is running can write directly to the mapper on the actual cart because the GPIO library can make the real pins show up in the memory space of the emulator. It's something that looks very reasonable from the software side, but as kevtris points out it might have some issues in the actual implementation, especially for 16-bit systems. The memory mapper (not to be confused with the mappers on the game carts) GPIO library I'm using for the Beaglebone Black tops out at around 2 MHz writing speed, so they'd have to have a notably faster one. Which isn't outrageous, they're using a much faster ARM and likely a completely different library. My concern would be that they've just discovered this capability and are looking for funding to implement it in emulators for higher-speed systems, like the Genesis. The biggest problem of course is the only thing that bypasses is the memory mapper portion of the emulator, which is probably one of the easier parts to emulate.

I believe there's an open source implementation for the PS1 BIOS already, I remember running it for a demo (don't remember which emulator, possibly PCSX-R?). Even yabause has a reversed BIOS for Saturn games. I think the standout ones are Sega CD, Turbografx CD (someone mentioned a game card that has the BIOS though), Jaguar CD, 3DO, and CD-i. There's definitely a pattern for CD systems. I'm coming from the perspective of the software emulators, I don't know how many of those implementations would be usable in an FPGA environment. I'm also assuming that the Retroblox is basically going to be 95% software emulators with the GPIO pins memory-mapped into the emulator's address space, so pointers from the emulated CPU access the actual ROM hardware. It's something I discovered with my beaglebone-black project, but I didn't pursue it since I didn't want to mess with low-level parts of the emulators for so many systems for what I felt was no real benefit. kevtris' warnings about timings makes me feel better about my decision, but we'll see what gets demoed soon. I'm curious to see how far along they are currently.

I'm glad you posted your explanation of the DMCA first, it makes more sense than what I had down. (also glad this forum lets you know when there's a new post, lol). Anyway... my problem with asking users to provide a BIOS in my view is you're asking them to go to the same dodgy websites that have all the games they're about to run. If someone's going to violate copyright to make a product work, why not just grab all the .iso and rom files while you're there and skip the middle-man? It's probably okay for an enthusiast product like what kevtris is working with, but for a regular person product like the Retroblox that doesn't seem like a reasonable approach. I still expect a reversed BIOS for the CD systems to be a stretch goal, or be limited to PS1 games.

There are PS1 emulators that don't require a BIOS. This is what I was talking about Sega CD being a stretch goal, I'm not aware of any Sega CD emu that doesn't need a genuine BIOS. Same problem with many of the other CD systems, mainly it's PS1 and Saturn in the clear. But with enough money and engineering, they can reverse engineer those BIOSs. It'll be hard to do, and they'll probably have to rely on the community some.

I appreciate the support. You're right, of course, I've even said anyone that's used both a Retron 5 and Retroarch would have the same idea. Or just a Retron 5 and any modern console.

I don't know if I should feel better or worse about the time I've spent working on a working prototype of pretty much the exact same thing knowing there's at least two other companies doing it. :/ Oh well, there's multiple engineering paths to go down, and I've been wondering which I should pick. Maybe this will help me pick. A lot of the problems with their current press release might be cleared up in the Kickstarter, where we discover Sega CD is a stretch goal, for example. I do hope this does well; the community is already burned enough after the Chameleon, a second screw-up will just make selling a proper product vastly harder.