Currently boots on board and can connect to REPL,
but does not appear as mountable drive in OS.
Starting REPL gives the following error message:
```
You are running in safe mode which means something unanticipated happened.
Looks like our core CircuitPython code crashed hard. Whoops!
Please file an issue at https://github.com/adafruit/circuitpython/issues
with the contents of your CIRCUITPY drive and this message:
Crash into the HardFault_Handler.
```
Dan Halbert
ladyada
Scott Shawcroft
Radomir Dopieralski
John Reese