Adafruit-circuitpython-rfm9x

To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

Adds snr and last_snr properties -- similar to rssi and last_rssi.


To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

pre-commit has been added to the GitHub Actions workflow in this repository. pre-commit allows you to run multiple checks, such as black and checking the REUSE licensing compliance, both locally and on GitHub Actions with one command.

You can run pre-commit locally with `pre-commit run --all-files`

To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

implement changes per the errata in https://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R000000HSPv/sqi9xX0gs6hgzl2LoPwCK0TS9GDPlMwsXmcNzJCMHjw

added a new kwarg "agc" which can be set to enable the automatic Gain Control - Default is False to disable so there is no change to existing behavior.
The only change to existing behavior is to set bit 7 of Register 0x31 per the errata. For all BW except 500K it is now set to 0.

To address some of the items in 51 several new attributes were added:
auto_agc -- set via agc kwarg or can be set manually after init
low_datarate_optimize - defaults to 0 can be set if desired
lna_boost_hf -- defaults to 0 (off) nay be set to 3 to enable
auto_ifon -- controls bit 7 of register 0x31 (used internally when setting BW)
detection_optimize - (use internally when setting SF)


To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

The reset sequence has been revised to remove the need for internal Pull-Up resistors.
No changes to user code necessary.
This is consistent with the TinyLoRa,RFM69 and Arfduino Radiohead library implementations.
To keep the RST line High during normal use, Instead of switching to an input with a Pull-Up enabled, it is kept as an output and set High.