I have a BME280 and a BME680 sensor and get reasonable readings for temperature and humidity (and gas). But the pressure is always around 955 hPa; +/- 2 hPa. Both, BME280 and BME680, measures always the same constant pressure (only the decimal place differs).
I use the official examples, also the BSEC example. Tried also some Python examples from the web, same result. Temperature, humidity (and gas) are ok, pressure always constant.
I have no clue why only the pressure is not valid, e.g. constant. What do I wrong?
Appreciate any help, hint, …
Thanks in advance
It is common to observe an "absolute offset" after assembling/mounting the pressure sensor. Such offsets are typically stable over time, which seems to match your observations. Therefore such offsets may be compensated by a one point calibration method (use a calibrated reference device in a stable environment right next to the sensor to estimated your offset, then subtract it from future pressure measurements). Using a calibrated reference device is strongly advised above weather station data to prevent any local weather or altitude changes to influence the measurements.
Thanks for your response.
I found that if I use the DFROBOT Library (containing BME680 Library), it provides a more expensive set of functions for the BME 680. I am able to provide an altitude to calibrate a Sea Level function, and then Fetch pressure compensated for Altitude, and its reasonably accurate. However when I tried to integrate the DFRobot library into my own sketch, I have run into problems with compilation, the subject of a separate message on this board.