Hi, Yes, this should be SW problem. If you initialize BME280 correctly with normal mode, oversampling for T, H and P sensors, then you can use the attached "sample_calculation_BME280.xlsx" to verify your SW. For example, you can manually type trimmed values from the BME280 chip that you are working with into the Excel file dig_T1 to T3, dig_P1 to P9 and dig_H1 to H6 cells. Then every time when you get the unsigned integers raw data for T, H and P sensors, you can manually type the values into the UT, UP and UH cells. The Excel file will calculate the final T in C, final H in %RH and final P in Pa. Then you can compare the results against what you get from the SDK from TI. If they match, then your SW is OK. Otherwise, there is a problem in your SW. Thanks. ... View more

Hi, Thanks for your inquiry. I think you may mean you read temperature data after power on, not power down. The temperature data should be stable, not increasing 25% and 50%. Please refer to BME280 API source code at https://github.com/BoschSensortec/BME280_driver about how to initialize BME280 and how to read sensor data. Thanks. ... View more

Hi, Thanks for your inquiry. It seems like BMF055 shuttle board works fine with your firmware, but you cannot program BMF055 that is soldered on your own PCB. Please check the soldering quality and let us know if all PCBs have the same issue or not. Please let us know which country you are located in so that our local FAE can support you further offline to be more efficient. Thanks. ... View more

Hi, Thanks for your inquiry. In BME680 datasheet the typical IAQ deviation from sensor to sensor is +/-15% +/- 15. The IAQ value [0, 500] is the output of BSEC library. If the reference meter shows IAQ of 200 for example, then the IAQ error from BSEC should be in the range of [-45, +45] which means that the IAQ output of BSEC should be in the range of [155, 245]. The accuracy of bVOC which is another output of BSEC in the range from 0.5ppm to 1000ppm is not defined or specified. Thanks. ... View more

Hi, Thanks for your inquiry. The issue comes from offset compensation and cross-axis sensitivity. If BMA253 Y axis is pointing to the sky or ground, then Y axis should be +1g or -1g respectively. You can run fast offset compensation and then store the offsets back to NVM. Then when you tilt BMA253 X axis or Z axis more than 45 degrees or +/-0.707g, the high-g interrupt should trigger. This process is so called inline calibration. Please see the attached PDF file for more information where you should set Y=+1g or -1g and X=Z=0g for fast offset compensation. In addition, when you tilt your device's x or z axis, BMA253 X or Z axis may not be aligned with your device's x and z axis. This is so called cross-axis sensitivity or misalignment. The best way is to do 6-position BMA253 calibration and store total 12 parameters (3x3 sensitivity and cross-axis sensitivity matrix and 3 offsets) into your MCU's flash memory. Then you always need to read BMA253 raw data and apply the 12 calibration parameters to get final x/y/z values. Then you can calculate the tilt angle all the time to see if your device is really tilted more than 45 degrees on x and z axis. The last reason is due to the BMA253 noise. you will not get the exact 45 degrees high-g interrupt. Instead, you will see a lot of interrupts at 45 degree tilt angle on and off. To avoid this situation, you should enable high-g hysteresis so that you won't get too many interrupts. Thanks. ... View more