Like many, initially I struggled with getting these devices communicating over i2c on NodeRED. I thought it mighe be helpful to publish an extremely basic flow for reading data, via the i2c inteface, from most of the Atlas-Scientific EZO sensors, circuits, and devices. One flow, one dashboard.
Note: there is an additonal flow and dashboard tab for Restarting Node-RED and Rebooting/Shutting Down a RaspberryPi.
This sample reviews retrieving data from the following:
RTD, pH, ORP, EC, DO, FLO, PMP, HUM
The folowing are not included, but the above code will be very easy to modify to accomodate them:
PRS, O2, CO2, RGB
Recall the intent of this flow is to help users to retrieve very basic measurements from the EZO devices and work with those values in Node-RED. Therefore, there are no provisions for configuration, calibration, compensation (e.g. temp comp for pH), nor database logging in this example.
However, in the case of the FLO circuit, you can Reset the Totalizer and with the PMP device, you can Command a desired amount to be dosed (simple quantity, not quantity over time).
This example assumes the default i2c addresses are in use. The devices must be configured to output the variables that are retrieved by the example. A few node-RED nodes must be installed. There are comments throughout the flow that indicate which variables are being retrieved.
Please take the time to read over the DataSheets provided for each device on the Atlas-Scientific website. They contain a wealth of information and will help you to move beyond this basic example quickly.
I hope some will find this very basic flow useful. Complex examples of flows that include some configuration, calibration, compensantion and data logging capabilities will be published in time.
Here is a link to the Flow.