Went to a Goodwill and looked through their bin of assorted cables on Monday and I found what looks like a link cable for a GBA SP. I'm specifically saying GBA SP since both ends of the cable have the same type of connector that the charging cable and headphone jack adapter have that go into the SP/original DS's EXT.2 port. It can't be for link cable stuff since the EXT.2 port isn't wired for that, just power and audio. I thought that maybe it could act as a sort of jumper cable to use another GBA SP to power your GBA SP as dumb and pointless as that'd be, but I got no reaction from either of my SPs when I plugged the cable into both. Looking at a pinout for the EXT.2 port doesn't seem to help much. This cable has four pins: detecting headphones, one side of audio, 5.2V power, and ground. Both ends have the same pins. Does anyone have any ideas what the purpose of this cable is? Does some other electronic device happen to have the exact same port as the GBA SP/DS?
https://imgur.com/a/HgsyH6R
