tempsensor.py example disconnects unexpectedly

[Remco-Schoeman]

at the line below the example waits for the connected client to disconnect.
What is not obvious is that awaiting this disconnected() call causes an disconnect after 60 seconds!

micropython-lib/micropython/bluetooth/aioble/examples/temp_sensor.py

Line 58 in 8058b29

await connection.disconnected()

It took me a long time reading code before I found the reason why: The timeout_ms parameter for the disconnected() call specifies a default timeout of 60 seconds for the wait, after which a CancelledError is raised, and the peripheral_task() exits, disconnecting the connection.

micropython-lib/micropython/bluetooth/aioble/aioble/device.py

Line 218 in 8058b29

async def disconnected(self, timeout_ms=60000, disconnect=False):

regrettably neither the CancelledError or the stacktrace give any clear indication of what happened.

As this is example code it might be nice to change the example to this instead:

    print("Connection from", connection.device)
    while connection.is_connected():
        temp_characteristic.notify(connection)
        await asyncio.sleep_ms(5_000)

which will push change notifications to the connected client every 5 sec or so, and not disconnect mysteriously (for micropython noobs like me in any case) after 60 seconds.

I can make a PR for this if desired.