Hey, just thought I’d clarify, in case people get confused.
This is a SUPER old thread from two years ago; with the last post made in August 2018, when the retroarch build and Clockwork OS didn’t have everything configured to allow keys to be detected. Back in those days, you couldn’t easily reconfigure keys, as trying to do so just resulted in a time out, and no new input detected. You had to manually edit the retroarch.config file.
These days, it is all working since upgrading to Clockwork OS 0.5 and Retroarch 1.8.x. See this post I made a while back.
Re: snes bindings, they’re going by the physical locations of the key, ie, X = North, Y = West, A = East, B = South. You can physically attach the keys to whatever you want. Dependent on the display, you may or may not need to change the configuration. In fact, ergonomically, it should be set to be the correct binding, unless you have flashed the firmware of the arduino keyboard to have SNES bindings; in which case you will have to change it. Most people would simply change it via the settings menu.