Use FiPy as comms controller for Raspberry Pi

[Costas Vav]

Hi, I see similar questions have been asked before, but my need is slightly different.

I have a device that is controlled by a Raspberry Pi Zero and has sensors, display, GPS, battery pack, etc. As this is a portable device, I want to use the FiPy to receive messages from the Pi and then send them over SigFox, LoRa or LTE-M, depending on content of message received. Therefore the FiPy does some logic processing and does not simply want to act like a modem for the Pi. WiFi/BLE is not needed, as the Pi already has it onboard.

What would be the simplest approach to feeding data into the FiPy from the Pi? Pi UART0 to FiPy UART0?

I already have a GPS connected to the Pi over UART0, but I will have to switch it to UART1, as the data going to the FiPy is more important.

Thanks!