As fallout from a conversation about I2C and the Adafruit NeoTrellis, here is a small code example which wraps an OSC sender and receiver around a NeoTrellis so you can talk to it.
This has been used with some success with Pure Data and C projects. The example itself really is no more than the underlying projects' examples, fused, with a tiny bit of Bela-centricity. If it's useful, hits a practical usability level and gets some feedback it can be improved and debugged.
Big caveat is that you need a newer Python than the one on the Bela. I have one which I can share and should think of a smart place to post it for download.