OK…Back in the Batcave now (i.e. my basement) and hooked up spare Rio with the SAME cheapie 9-pin to USB adapters and – as Ben predicted – the results are not the same as the EPIC. Plugging in either displays this:
I realized on my drive home that all I really want to accomplish at this point is using Node-RED to read my serial data, which was answered in this thread already. On the EPIC, I really don’t need the 9-pin to USB adapter…it must have been the 8-week hiatus that got me going down another path.
Thanks again guys!
PS: Also cancelled my order with Amazon for the other USB adapters (thanks Philip)