I've been having two separate problems with my old USB BleepBloop cartridges.
1) The UCP cart programmer software is "timing out" when I try to load new ROMs onto the cart (or to erase the old ones):
Does this have to do with the filesize? The program I'm using? (I'm attempting to load a copy of LSDJ modded with littleFM. Tried to load a friend's GB Studio rom also. Same result.) It writes SAV files just fine.
1.5) Here's the cartridge I'm trying to use. This works fine on my Game Boys but I can't upload a different ROM onto it, as I said. It's the same exact cartridge type as the ones that have this next problem.
2) A couple other BleepBloop USB cartridges of mine display this screen when I turn on a DMG. I can't use them at all.
If I'm lucky, I can get it to run on a GBA. If I'm unlucky, it just shows the GBC startup screen with the Nintendo logo looking like a reduced version of this. (same problematic result on a GBC.) This happens no matter how far in I put the cartridge. If I take off the top shell and just slide the PCB and back-layer of the shell into the console, this still happens.
On one of my cartridges, an early one with a red PCB, I followed some old, forgotten advice from nitro2k01 and loosened the security bit screw. Now it works!--on this one cartridge. This does not help with the other ones with the white PCBs, however. I even changed the battery on them for fun, but no change.
"sounds like you have a lot of cartridges, Sloopy" yes, yes I do. But I use them all... all the ones that work!