README.md

rpi-iaq-monitor

Simple C++ application to monitor IAQ (Indoor Air Quality) using a RPi4 and a BME68x sensor accessed via the I2C bus.

The values are published to a given instance of HomeBridge (can be easily disabled in main.cpp), the URL of the HomeBridge instance needs to be set in src/constants.h.

Dependencies

build-essential, cmake, libssl-dev, libspdlog-dev, libi2c-dev, raspi-config, gdb

Configuration

• Download the BOSCH software from https://www.bosch-sensortec.com/software-tools/software/bme688-software/

• Copy libalgobsec.a to bsec/lib/.

• Copy the following source files

bme68x_defs.h
bme68x.h
bme68x.c
bsec_datatypes.h`
bsec_integration.h
bsec_integration.c
bsec_interface_multi.h

in bsec/src/.

• Enable I2C on the RPi with sudo raspi-config.

  To enable I2C select 3 Interface Options then I5 I2C.

• In the bsec_integration.h file

  change SAMPLE_RATE when OUTPUT_MODE == IAQ (line 114) to

  #define SAMPLE_RATE BSEC_SAMPLE_RATE_LP.

  to match the configuration used by air_quality_service.cpp (feel free to use another one depending on your needs).

Compilation

mkdir build && cd build
cmake ..
cd ..
cmake --build ./build --config release --target all -j 6 --

Run it

cd build
./air-quality-monitor

Note: It will take some time for the IAQ accuracy to change.