If you have connected directly to the Hydrom via your WLAN, you will need the IP address of your device. The page to be called up is then as follows: http://<IP-Address>/mpucalibration
The LEDs will now flash.
Step 4: Wait
The Hydrom will now measure the current position frequently and then determine an offset for the attitude sensor based on changes in the measured values. Once the LEDs stop flashing, the attitude sensor is calibrated.