The Industrial Raspberry Pi Forum

Hello.

I am trying to figure out, how you guys are able to display a float temperature of the core cpu in the web interface status board like 50,4 °C.

My program is using the revpimodio2 module for python, but the 'piTest -r Core_Temperatur' command is also returning without the desired precision.

Google "how to display Raspi CPU temperature" will show you dozens of websites explaining methods in all kind of applications. Basically the Broadcom SoC gives you a 1/10 °C precision. So if you need it more precise you could use the following system command:
vcgencmd measure_temp
We only use the integer part for our process image as this is physically precise enough for 99% of all questions especially if you keep in mind that the sensor's precision is limited. Therefor piTest or any other software using piControl to access the process image will only give you integer results for the temperature.