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1. Get the RadioHead library from [http://www.airspayce.com/mikem/arduino/RadioHead/](http://www.airspayce.com/mikem/arduino/RadioHead/). There is a link with the ending _.zip_ that you can click to download.
2. Add the library to your Arduino IDE. One Once added , you can open the example file under examples --> radiohead.
3. In the (example) sketch, make sure to assign LED to something other than 9. If set to 9, the restart of the LoRa board will be triggered.
This [_dfrobot_ tutorial](https://www.dfrobot.com/blog-1161.html) leads you through installing the Nanopb library and compiler on your laptop. _Nanopb_ is a version of the protocol buffer in the programming language C, which works well with 32 bit systems such as the Arduino. You can use [this online proto buffer decoder](https://protogen.marcgravell.com/decode) to decode proto buffer messages that were encoded for sending.
Protocol buffers are a data serialization format from Google which are supported in multiple programming languages. Protocol Buffers messages are encoded in a binary format, which means they are not human-readable unless we decode them back to a readable format. One of the main advantages of using Protocol Buffers is that the serialization and deserialization process is fast and the generated messages are small.[^protob] The Nanopb library needs a '`.proto' ` file that clarifies the variables that will be serialized. Once, the different types of variables are serializedor encoded, they are unreadable for humans in a binary format. This number is expressed as a hexadecimal that can easily be sent over wireless radio as it requires small amounts of data. The encoded message needs to be decoded on the side of the receiver. The receiver also needs to know the specific variable types in the message to properly decode the message. The [abovementioned tutorial](https://www.dfrobot.com/blog-1161.html) only walks you through setting up the Nanopb environemnt on your laptio and encoding a message. A [different tutorial by _dfrobot_ shows how to encode and decode messages between an Arduino and ESP32](http://dfrobot.blogspot.com/2019/02/esp32-arduino-tutorial-25-3-protocol.html).