You can't make every emulator support your game. Older FCEUX likely doesn't support your mapper. If you can reduce the size to 256 KB or 128 KB, then it might. If you need that extra space, then move on.

This game is using oversize UNROM. Presumably older FCEUX does not support this variant of mapper 2, while newer FCEUX does. Generally, when an emulator did not support a game and now does, it's an improvement to the emulator and not an indication the game has a problem. For what it's worth, I have ...

If it doesn't work in old FCEUX and does work in new FCEUX, I would not be concerned. Newer versions are very different from older ones because of a multi-year gap where development continued but releases weren't made, and FCEUX is not exactly a highly accurate emulator. The game starts just fine in...

The CPU/PPU alignment is random at power-on and random whenever the PPU is reset because the PPU's clock divider is affected by reset; however, not all consoles reset the PPU on reset, so console reset may preserve CPU/PPU alignment. NES-001 and FamicomBox are the only consoles I'm aware of that res...

Regarding even/odd CPU cycles, I believe this is misleading terminology and should be retired from the wiki. This is trying to express that certain things only happen on one half of the APU clock or the other. However, my understanding is that the alignment between the CPU and APU is effectively ran...

I think the language barrier is making it difficult to help you, and NESdev is also more focused on research and development of new games, not ROM hacking. You may have more luck at romhacking.net with these kinds of projects. It might also help if you wrote in your native language, because there ar...

I can test across at least a few different consoles.

As for other places, the Discord server is pretty active, and a lot of NES stuff gets posted on Twitter.

Sound quality should just be determined by your writes to $4011 - their timing and the values you use. Keeping NMI off and not using sprites shouldn't cause any sound issues.

Note that you can still write OAM manually during vblank at a substantial cost, allowing you to sprinkle $4011 writes throughout at the right times, and you can cut down on this cost by limiting how much of OAM you use and accounting for the glitches from updating $2003.

This is the primary emulator subforum here, and moving it to 'Other Retro Dev' would suggest it is for non-NES use cases. I think this is the best place for this thread to be.

While my guess would be that this is 9v DC center negative, you should be very careful about power because supplying the wrong thing can damage or destroy the console. Figuring out the polarity is critical. If you have a multimeter, I suggest opening the system up and seeing which part of the connec...

For what it's worth, I've been using Mesen v2 for at least half a year as a tester, and in my experience, it's currently stable, works at least as well as the old one, and has worthwhile improvements to accuracy and functionality. For the NES, I don't think there's any reason to use the old version ...

Indeed, it's possible you're putting the cart before the horse here. Ideally you pick the mapper that is necessary for the game you want to make, and pare back the game as needed if hardware with features you want isn't feasible due to cost or availability. The question should be less 'Should I use ...

1. Going by nescartdb.com, MMC5 was used in 8 games in North America and 14 in Japan. It's not rare, but unlike common mappers like MMC1 and MMC3, original chips are not available in large quantities and there is no modern clone version. I generally try to direct people away from projects for which ...

You do not need to change the crystal. The device being PAL is not your problem, and obviously PAL systems do work because they manufactured and sold them this way. You only need to change the crystal if you need this to be an NTSC console. 1. Try swapping your Game Boys. This should be trivial; the...