I’m trying to scan a folder with NES roms. They’re uncompressed *.NES files. I can run them with any NES core, but they do not seem to be recognized. I updated the databases and core info files. What could be the issue?
Could be headered/unheadered mismatch?
To tell you the truth, this headers/un headers thing has been explained to me time ago, but I’m not sure I understood it…
NES carts used some tricks to provide more resources than the console was designed to deal with, but emulators have no way of knowing what tricks were used, as it’s not contained in the game information but rather the hardware itself. So, emudevs started putting in little codes in the unused portion at the beginning of the ROM to provide a hint. For a long time, no emulators could run the ROMs without the hints, but many newer ones can consult an internal database to figure out how it works (Mesen does this, and I believe Nestopia’s NstDatabase–which is baked into the core now, IIRC–can do the same).
Some ROM databases from No-Intro include the headers and some don’t, and there’s a reasonable argument for doing it one way or the other. Unfortunately, if your ROMs don’t follow the same convention, they may run just fine but simply not match because of the presence of a header or lack thereof.
Thanks for the interesting insights. I honestly have no idea how I can tell if the roms I have are headers or not. The Retroarch scanning process does not ask for a core, though, because if I’m correct it only relies on its databases. What version of the roms does Retroarch want? Headers or not?