1 Reply Latest reply on Jan 20, 2019 8:46 PM by MoTa_728816

    I2C (and SPI) Temperature, Humidity, Pressure and Gas Sensor (BME680)

    MoTa_728816

      I was looking for an air quality sensor,

      although I've tried some, controlling heater of the sensor

      was somewhat difficult and so far I have not had any reasonable

      read-out from the sensors/modules I've tired.

       

      Then I came across this one, the heater can be controlled via I2C or SPI.

      So I gave a try.

       

      It was easy up to read and write registers via I2C,

      then I noticed that configuring the parameters and

      calculating the read value to something reasonable

      were not quite easy.

       

      So it was the time to read the datasheet seriously,

      and I found that Bosch was providing a couple of lifesavers.

      (1) Open Source Driver via the github

      https://github.com/BoschSensortec/BME680_driver

       

      (2) Bosch Sensortec BSEC Software

      http://www.bosch-sensortec.com/bst/products/all_products/BSEC

       

      Since (2) requires SLA (Software License Agreement), I decided to go with (1).

      Note: To calculate the gas resistor value to IAQ Index probably (2) is required.

      BME680_MRB_SS.JPG

      001-BME680-schematic.JPG

      The open-source driver also came with self-test.

      Which is quite helpful to confirm that the hardware is at least functioning.

       

      But meantime, I noticed that as the self test utilizes heater a lot,

      after the test, the temperature read outs starts rather high.

      000-TeraTerm-log.JPG

       

      moto