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There is an example of how to do this for I2C in the PI3G python wrapper, available in github https://github.com/mcalisterkm/bme68x-python-library-bsec2.6.1.0/blob/main/README.md  BSEC 2.x includes I2C/SPI comms, but if you are just using the API then there are the references to coines which may not be available for your platform. That is the case for the Raspberry PI, and bme68xmodule.c uses ioctl calls on the I2C device.  The bme68x_i2c_read/coines_read_i2c (and write) are mapped in the API common.c and in the PI3G python wrapper replaced by pi3g_read (and write) see internal_functions.c. Sorry it's not SPI but it does show how to replace COINES comms initialisation, read, and write.  I recall that there are other integrations on GitHub for the BME688 that do a similar replacement of COINES in order to use the API.  Regards Keith ... View more

The integration guide that comes with the BSEC library covers how to call the library on page 15 - initialise the sensor, initialise the library, subscribe to outputs (based on the config you have from AI Studio),  update subscriptions, and walk through the outputs. See the examples folder and bsec_integration.c. In my experience when scanning/sniffing for subscribed substances, the standard environmental values such as Temp go haywire and should be ignored.  You can subscribe to 4 target substances and use the IA Studio classification or regression algorithms, as best fits your use case.   If you are scanning/sniffing continuously then you probably need a second sensor for the environmental data. That could be another BME688 using the BSEC  multiplex interface or an alternative sensor like a BME 280 (but not using BSEC). Keith ... View more

Yes you can buy the HUZZAH-32 and add it to the BOSCH Sensortec Devkit.  The tools needed to flash the Huzzah run on Windows (see the BME688 Development Kit software v2.1.5) available from Bosch here #Devkitapp  I have a tutorial that walks through that install, here on GitHub  Hope that helps Keith ... View more

I did some work on the 688 in ULP mode connected to a Raspberry PI4 which draws between 2.6w and 3.1w bouncing up and down every 4 to 5 sec (includes an ssh login). Placing an ammeter (on the 25 mA scale) in the power line between the PI and the BME688 (I2C) then running a parallel mode python script (300sec), the meter flicks up to 13mA every 5 min and sits at zero mA the rest of the time. Hope this helps Keith The BoschSensortec spec suggests an average of <0.1 mA but as your test shows ULP is very spikey. ... View more

That is an I2C connection - 3.3v,  Ground, Data, and clock.  It looks like you have the option of soldering on to the labeled pads or using the connector, which probably has the same pin outs.  Your Pi4 raspi-config utility will allow the I2c interface to be enabled, then look to install i2c-tools (apt install i2c-tools) which has the i2cdetect tool that will find the port this board is using.   The GPIO pinouts for a PI will show you the layout of the GPIO pins - google search.   GPIO 2 and GPIO 3 are SDA and SCL respectively for the default I2C bus 1.  There are multiple GPIO pins that offer 3.3v and Gnd. Note: GPIO and board pin number are two different numbering schemes. Regards Keith ... View more