A Feather board without ambition is a Feather board without FeatherWings! This is a Wing board for the SP3485 RS-485 transceiver IC, which will convert a UART serial stream to RS-485. The SP3485 is a half-duplex transceiver, so it can only communicate one way at a time, but it can reach transmission speeds of up to 10Mbps. This board requires a very low amount of power and can operate from a single +3.3VDC supply.
Works with all Feathers except for those with USB-Serial converters that use the UART pins. Right now that means the ESP8266 Huzzah Feather and nRF52832 Feather don’t work.