BME280 wrong temperature value

[hetres_123]

Hi,

We are using BME280 to read only temperatures. Most of the time we read correct temperatures (98%). But sometimes, we read wrong temperature value. We have multiple BME280 devices, and same firmware is flashed in all the devices. But only 1 is causing the problem.

We figured out that this is due to reading wrong register value (calib00-calib25).

Most of the time we read correct values from this registers, and we observe wrong temperature value when we read wrong calib register value.

Before reading the temperature we apply reset sequence to the sensor each time, for reliability. 

Correct Register Value (0x88) (calib00-calib05). -> {0xFE , 0x6D , 0xDF , 0x67 , 0x32 , 0x00} --> We read correct temperature value

InCorrect Register Value (0x88) (calib00-calib05). -> {0xFE , 0x6D , 0xDF , 0x67 , 0x32 , 0x23} --> We read wrong temperature value

Could you please let us know why just one calibration register value is changing sometime ? Has the sensor gone bad ?

[BSTRobin]

Hello hetres_123,

Do you use BME280 driver code in github?

https://github.com/BoschSensortec/BME280_driver

[hetres_123]

Yes, we are using the same code.but have slightly modified to read only temperature

[hetres_123]

Could you please provide us a solution how to proceed ? How can we make sure that the sensor is functional ?

[BSTRobin]

Hello hetres_123,

Could you run it with the unmodified example code?