It seems there are three ways this might be done:
- Use the built in BLE functionality,
- Find some way to attach a BT device to the USB-C port,
- Modify the firmware so that the RX and TX pins can be used for the terminal.
I'm no expert in USB-C, but I don't think I'll have any success finding a a BT module that's also a USB-C host.
That leaves me with #3 which might be a nice feature, but if I recall from past experiences, abstracting serial ports isn't trivial.
My device will be hard to get at, and often under water. When not under water, I'd like to stream live data (very low sample rate) and download previous data without opening up the sealed enclosure.