Retropie controller trouble

[abo]

I'm running Retropie 4.6 on a 2GB Pi 4, purely to run arcade roms. I bought some joysticks and buttons from EG Starts on Amazon and put them all into a temporary housing to make sure everything works as it should. This is what I have:

https://www.amazon.co.uk/gp/product/B07B63SBJR/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

I'm using the official Pi 4 power supply and have added some heatsinks.

I've wired up six fire buttons, the start button plus a spare button for the hotkey, for each controller as per the wiring diagram - fire buttons plugged in to K1-6, hotkey into K7 and select/start into the sockets as labelled). If I plug one controller in (either one, doesn't matter) I can set it up in the controller config menu just fine and everything works as a Player 1 controller.

However... When I plug the other controller in, I can configure it as above and everything appears to be fine. However, when I launch a two player game I run into trouble in that the Player 1 start button has become a fire button, one of the fire buttons appears to be empty and select has become P1 start. The Player 2 controller at this point works fine. This also means I cannot use the hotkey/start combination to exit the game with the affected controller.

Then, if I go back into the controller config menu and set up the Player 1 controller again, it breaks the Player 2 setup in the same way. Reconfiguring the Player 2 controls ping-pongs the problem back to Player 1.

I've had a look at the config menu when running an actual rom and it reports the buttons are configured correctly.

Any idea where I should take my troubleshooting next? Is there anything in the Retropie configuration I can check (Retropie noob here...) Could this be an encoder issue?

Thanks

[mitu]

@abo said in Retropie controller trouble:

Could this be an encoder issue?

Sort of. Because both controllers are identical (in name and model), the same input configuration is applied to both. If configure one of them, the same configuration is applied to the other (and vice-versa).

What you need to do is ensure the inputs are wired identically - i.e. Button A on P1 uses the same wiring position as Button A on P2. You can't mix and match.

[abo]

That did it! There was a wiring problem with the hotkey. I just unplugged it, configured select as the hotkey for both controllers and now it is running perfectly. Thanks :)