Gayland Monken asked 6 years ago
Rui and Sara,
I just finished the above course and everything worked perfectly. Thank you for a great course and the accuracy of your book.
I now would like to build on to the last project and add another DS18B20 temperature sensor or two. Is this possible with little additional coding? Also could the temperatures be graphed in different colors on the same chart?
Again thank you for this course.
Gayland
Sara Santos Staff answered 6 years ago
Hi Gayland.
I’m really happy that you’ve finished the eBook already and that everything went well.
The DS18B20 communicates via 1-Wire communication protocol. So, you can read several temperature sensors wired on the same GPIO.
The code that starts on page 243 has a function called read_ds_sensor() that scans temperature sensors and then, reads the temperature of the sensors found. That function should work fine to return the temperature from several sensors. However, you’ll need to change the code so that you know which temperature corresponds to which sensor.
Yes, you can plot different series on the same chart on Node-RED. I’ve found this great tutorial showing how to do that: http://noderedguide.com/tutorial-node-red-dashboards-multiple-lines-on-a-chart/
I hope this helps.
Kind regards, and thank you for supporting our work.