Exploring soil moisture sensors

Connecting to a soil moisture sensor via The Things Network (TTN)

In this lesson we are going to connect to a soil moisture sensor.
The soil moisture sensor is connected to an Arduino MKR 1300 microcontroller (a small computer).
The data will be transmitted to the LoRa network.
LoRa is short for Long Range radio communication.
The data is then sent to The Things Network, which is a community run server that collects data from sensors and makes the data available for download.
We will download the data to our Raspberry Pi, and in future lessons display that data in a Dashboard using Node-RED.
All these skills are very important in helping to address Climate Change and general Environmental Sustainability issues the world faces.

In this lesson we are going to use Node-RED as our main programming tool.
Node-RED is a block or node based programming language.
Each block has a discrete function and some blocks can contain Javascript code or be configured in different ways.
Blocks are connected together using wires.
Node-RED and the programs on the Raspberry Pi are always being updated, so it’s normally good practise to update our Raspberry Pi on a regular basis.

This command will update all the software libraries on the Raspberry Pi, so that if we need to install software the Pi will install the latest software packages.
Enter the command sudo apt-get full-upgrade -y
This command will upgrade the entire operating system on the Raspberry Pi.
The -y option tells the computer to answer Yes to any questions.
The upgrade will take between 5 and 30 minutes to complete.
It is always to do this once every month.

The display on your Raspberry Pi will be different, but similar enough.
When using Node-RED it is important to stop Node-RED when you are shutting down your computer.
To close Node-RED open a new Terminal window and enter the command node-red-stop
To re-start Node-RED enter either node-red or node-red-start