RPICT and Node Red hosted on Raspberrypi
Make sure any program using the ttyAMA0 serial is off (emonhub, python programs etc).
We assume a fresh install of Raspberry Pi OS in this document.
Make sure the steps to setup the serial port have been completed first.
Howto setup Raspbian for serial read
Install Node-Red as follow
sudo apt-get install nodered
Start Node Red
node-red-start
You will see a similar message to this below at the top
Once Node-RED has started, point a browser at <http://192.168.1.206:1880>
Open a browser and go the indicated address. http://192.168.1.206:1880 for us here.
How to setup Node-Red depends on what the user wants to achieve. We will show a simple example here to split the data from the serial string.
Start to build a flow with a Serial Input a Function block and Debug output.
Now setup the serial port as shown below:
Then enter the java script in the function. Make 3 outputs are selected. Modify the script to your needs. We will just provide NodeID the First Real Power and Vrms from a RPICT7V1.
The code is here below for copy paste.
var output = msg.payload.split(" ");
var NodeID = parseInt(output[0]);
var RP1 = parseFloat(output[1]);
var Vrms = parseFloat(output[15]);
var msg1 = {payload : NodeID};
var msg2 = {payload : RP1};
var msg3 = {payload : Vrms};
return [msg1, msg2, msg3];
The right pane debug will show the split values.