update BLE remote control switch; not tested

[dhalbert]

This updates the code for https://learn.adafruit.com/circuitpython-ble-remote-control-on-off. Needs testing by @rdagger.

[dhalbert]

@rdagger do you have time to review this, and still have the hardware set up? Procedure would be to:

1. Update CircuitPython to 5.0.0-beta.0 (from https://circuitpython.org/downloads)
2. Update needed libraries to latest (from https://circuitpython.org/libraries)

Thanks.

[rdagger]

Did a quick test:

Client code through the following error:
File "code.py", line 63, in
AttributeError: 'BLEConnection' object has no attribute 'in_waiting'

The server code didn't throw an error but when I tried to connect with the Bluefruit Connect app, I received the following error on my phone:
"Uart protocol can not be initialized"

I'm using Adafruit CircuitPython 5.0.0-beta.0-45-gd154d1191 on 2019-11-25; Adafruit Feather nRF52840 Express with nRF52840 and the latest version of CircuitPython Bundle and Adafruit_BLE.

[dhalbert]

@rdagger OK, I fixed some code in client.py. I am not getting an error on server.py: it connects fine from my iPhone 6S running the latest OS and app version. What phone are you using?

[rdagger]

@dhalbert Google Nexus 6

[dhalbert]

Charging up a Samsung Android tablet to check.

[dhalbert]

I connected with Samsung Tablet, though I had a failed connection first, and then reset the Feather, and it worked second time. Not sure what that was about (maybe leftover connection from iOS).

[rdagger]

@dhalbert I restarted my Android phone and the server code is working now using the Bluefruit phone app.

[rdagger]

@dhalbert I spoke too soon. After a few minutes I received the following error from the server code:

Traceback (most recent call last):
File "code.py", line 47, in
File "code.py", line 45, in
File "adafruit_ble/services/nordic.py", line 108, in write
File "adafruit_ble/characteristics/stream.py", line 49, in write
_bleio.BluetoothError: Unknown soft device error: 3002

[ladyada]

@dhalbert @rdagger given many updates in the BLE core in last 2 months, should this be re-tested?

[dhalbert]

it's on my list to rewrite. :)

[TheKitty]

@dhalbert - is this PR pertinent given the latest work? I'm looking to close open Learn PRs. Thanks