The Industrial Raspberry Pi Forum

I've got a revpi connect with an ethernet/ip module communicating with a feather 32u4, currently over the USB connection. I'm wondering how reliable it is in the long term, what can be used to maintain reliability, and what alternatives are available.
I've previously tried using a ttl to rs485 convertor, which works fine with an arduino (328p) but not with the feather. I've also read around that I2C isn't available, and while SPI is across the bridge, it seems complex to implement.

Hello grphine, can you make a sketch of your application? This helps me to understand the open questions.