@fedesilvi I recommend you try PySimpleGUI It's much easier to program a GUI in PySimpleGUI than PyGame. Do you have tkinter on your platform? You should be able to hook up your GUI to anything you want. To display your information, read the data using your code, then plot the data using a Matplotlib / Pyplot call. You can then display that graph in your GUI. There is extensive documentation on how to use it and there are several example programs posted the demonstrate hooking it up to Matplotlib.

Sorry to grave dig, but had I known this earlier it would have been helpful. This post is about the Decagon 5TM, which has two protocols, SDI-12 and DDI. The DDI is typical UART at 1200 baud, which you can read from any UART reader. I've tested it with an FTDI cable and know it works with a LoPy. You do however have to power cycle the sensor to get a new reading. Note: This may not work on new Decagon 5TM sensors if you have changed the SDI-12 address to anything other than 0. Factory default is 0. If you have not used SDI-12 to communicate with the sensor then it should work as expected. We used a mosfet to turn the power on and off for the sensor, controlled by GPIO. Reading the UART within 10s of milliseconds from turning the power on will give you your readings. Its all explained in the integration guide. http://publications.metergroup.com/Integration Guides/18237 5TM Integrators Guide.pdf I know this doesn't help with SDI-12, but jubbs is using the 5TM specifically, which has this dual protocol stack. The sensor was also just powered from 5 volts (same supply source as for the LoPy), the 5TM supports 3.6V-15V, check datasheet for more information including current draw.