Show HN: OpenThread Mesh Gateway with BG95-M3 Based LTE-M Support

I would suggest that the absolute minimum functional requirement for an LTE-M mesh gateway is that it can receive outgoing messages from the mesh and then forward them over LTE-M via the onboard modem. We could then quite easily implement a mechanism on the OTBR that reports running firmware versions on mesh nodes and checks for any scheduled updates in Span. Since we now can receive mesh messages, we are in a position to forward them to our modem. It's kind of cool to implement an LTE-M mesh gateway that runs on 22 lines of Python :). First, we will start our Python script on the Raspberry Pi. We will then move over to the command line shell that we have opened on a mesh node and check the state to verify that it is part of the network. We can see that the message that originated inside the OpenThread mesh network has been successfully routed through the gateway, over the mobile network, and into Span. Since the nRF52840 can easily be adapted to the role of an I2C or SPI Peripheral in a different context, it should also be entirely possible to make this gateway play nice with other mesh protocols as well. Higher-level protocols will have to be implemented on top of I2C/SPI to interface the local mesh node firmware with code running on the Raspberry Pi, but that doesn't require any hardware changes.