When attempting to compile using Debian I was getting kernel panics and references to null pointers in memory. After trying a different SD Card, Cables, and power sources everything has only began to work once I've bought a new Pi.

I can only assume I've got a faulty unit?

Regardless I'm now able to run RetroPie on the exact same setup (with the Pi swapped out).

Actually, being in the RetroArch menu is similar to being in an emulator, none of my controllers seem to register (except arrow keys here). Frustrating, have to pull the plug again.

Like a guess that you aren't using a libretto core PSX emulator.

@maksi opens the RGUI menu - https://github.com/retropie/retropie-setup/wiki/retroarch-configuration

I accessed the retropie settings > misc > reicast options about adding a controler, and dimply ran that and told it to add the same PS3 pad, it asked for a few bindings which I set and others didn't (such as 'c' and 'z', no idea what those correspond to the dreamcast controller)

anyway now it works, no idea why it just stopped working. I did do a full retropie update yesterday though.

Okay, my mistake: tried out the Ipega controller again and ES (and, apparently, Retroarch) doesn't consider it to be a gamepad at all. DS4 is recognized, however.

Also, I don't have a working wired controller now, unfortunately.

Anybody got any answers for this yet?

Found the problem!

The PCSX-ReARMed.rmp file in /configs/psx/PCSX-ReARMed folder had only configurations for player 1, so I just duplicated the lines for player1 for player2.

Not sure where the wrong configs come from, but this overrides them.

Indeed it was the problem, I restored the original file with # char. That's ok, everything is working. Thanks for your help

@Vampire337 please, mark your topic as solved.

@mediamogul you are correct about my joysticks Axis... the only hope I am holding on to, is when the mode button is enabled, my Dpad values go from hat #0/#1 to axis 4&5/6&7... My end game is two have two players on mupeb64plus. Thanks for the replies guys!

The wiki should probably redirect people to use the menu option. It didn't even have the warning at one point - Sometimes there is out of date info there.

Any luck with dualshock 4 controller?

I had no issues setting it up over bluetooth, but the latency is horrible. It's definitely related to the controller not the game, as my ancient logictech wireless (usb dongle) controller has no noticeable lag.

Here is a screenshot of how I had it setup.
Originally I set it up with a keyboard being connected to the Pi, however I have moved on to SSH.0_1473220343423_Capture.JPG