BMP280 Pressure Sensor Incorrect Pressure Value

I am trying to use the BMP280 sensor from Adafruit. I have found the BMP280 library, have wired in the sensor and am getting readings, however the pressure reading is wrong. I am getting 84.1kPa but should be getting 92.6kPa. I have read where the altitude reading changes as the weather changes and can change the input value to correct the altitude.

The datasheet and Adafruit make it seem like there is no calibration for the pressure? Is this true? Am I forgetting something?

Could the sensor be damaged?

You should have a line where you define the sea level pressure. Did you do that?

#define SEALEVELPRESSURE_HPA (1019.00)

I tried changing the sea level pressure but that only changed the altitude reading… and not the pressure…

I get that same result when I test my BME280. It seems that the pressure reading you get from the library is absolute, not corrected for your altitude. What is the altitude where you’re testing?


Is it possible to calibrate the sensor based on elevation?

Did you buy your devices from Adafruit?

You may also want to try the SparkFun library?

It seems that the pressure reading you get from the library is absolute

The is correct. See BME280 data sheet: > Page 3, General Description:

The pressure sensor is an absolute barometric pressure sensor …

Sure, you could just use the ratio of what you know to be the true value to the value you get to correct the value. However, when I plugged the values you posted into an online calculator, I got an altitude of 2600 feet for your location. How did you determine what the correct value should be?