Description of calibration values of BME280

[jb_ict]

I am integrating the Bosch BME280 chip into a new product, and I'm looking for the meanings of the calibration values. E.g. dig_T1, dig_H2 etcetera. I would like to understand the compensation formula.

[BSTRobin]

Hi jb_ict,

In BME280 data sheet, we recommended using the sensor API directly.
BME280 sensor API on github: https://github.com/BoschSensortec/BME280_driver

[jb_ict]

Thank you for the quick reply. I am aware that the Bosch API is strongly recommended, and I am not against using it, however I would like to understand what the API is doing with the calibration parameters, rather than using a "magic" function.

Any help would be appreciated.

[BSTRobin]

Hi jb_ict,

The sensor API is written with reference to BME280 data sheet, and the detailed information are described in "Chapter 4.2 Output conpensation" of BME280 data sheet.

[jb_ict]

Hi BSTRobin, thanks for your response.

Are you referring to table 16 of the datasheet? Because while that offers insight into the data types of the compensation values, they offer no insight into what they actually represent. I.e. are they temperatures, offsets, pressure values or something else. The only description I see is e.g. dig_T1. I'm looking for what the value of, for example, dig_T1 means.