ThingSpeak Settings

ThingSpeak is a free cloud service that stores and displays IoT data. Integrated support for MATHLAB allows also for data analysis.

HomeLab software for ESP8266 and Raspberry Pi can access this cloud service to continuously send the data measured by the module. So the user can utilize a ThingSpeak account as a dashboard. The HomeLab Raspberry Pi software may additionally retrieve ThingSpeak data graphs and visualize them in its user interface.

To register a ThingSpeak account it would not take more than a couple of minutes. Go to and do it. An email box has to be available for the account verification.

For RPi users setting a data channel as shown below would suffice. The ESP8266 module connects the service via the MQTT protocol. So ESP8266 users have to also register a ThingSpeak MQTT Device.

Create a Data Channel

In the freshly created account go to Channels > My Channels and click the New Channel button. Give a name to the channel and activate the first 3 fields of the channel. These will be accessed by our software to write the pH, temperature and voltage values respectively, in this order. See the picture.

Save the channel.

In the new screen go to API keys and look for 3 items: the Channel ID, the Write API Key and the Read API Key. See the picture.

Write down or copy their values for later use. Click around the channel menu to see you can do other useful things here like clearing your data or making the channel private.

Set an MQTT Device

In case a data channel is already available select Devices > MQTT and press the Add a new device button.

Write down the device name and select a data channel.

Press the Add Channel button.

Take note of the channel ID and press the Add Device button.

A new MQTT device is added. Its credentials have to be downloaded as they are needed to connect the HomeLab software to the ThingSpeak dashboard. Select 'Plain Text' option and open the downloaded file. Then press the Done button to finalize the procedure.

To connect the device its credentials along with the channel ID (see above) are needed.

The new MQTT device with a channel to subscribe and publish to is ready.