Specific values ​​are often measured in bme680

[sanghee]

Specific values are different for each bme680 sensor

In some sensors, a temperature value of 3350 is often measured.

The actual temperature value is about 2832,

Actual temperature value and specific value are measured almost alternately 

The actual temperature value changes depending on the temperature

But that particular value, measured almost alternately, does not change.

Why are these useless values ​​constantly measured?

[FAE_CA1]

Hi,

Thanks for your inquiry.

BME680 is 4-in-1 sensor. It only measures temperature, air pressure, humidity and VOC gas. That means BME680 will convert these 4 measurements in digital domain with raw data integers and put them in data registers.

Each BME680 chip is factory trimmed, calibrated and tested before it goes to the market. Those trimmed values are stored in the NVM of each BME680 chip and they never change. Every time when you get raw data from BME680 data registers, you need to apply those trimmed values to the formula in BME680 datasheet together with the raw data integers to calculate the final temperature (C), air pressure (hPa), humidity (%RH) and VOC gas (kOhms).

Thanks.

[sanghee]

thanks for answering

I am already using the bme680 library I got from github

Should I use more formulas?

[FAE_CA1]

Hi,

All formulas are already implemented in BME680 API code on the Github. You don't need to use more formulas.

Thanks.

[sanghee]

then what's the reason

that Actual temperature value and specific value measured almost alternately?