Reference

Library

• DFRobot_BME68x: Arduino library for BME688 sensor.
• BME AI-Studio software: For AI-based gas analysis.
• BSEC2-Arduino library: Required for BME AI-Studio integration.

Communication Protocol Description

• Interfaces: I2C (default) / SPI.
• I2C Pins: SCL (C pin), SDA (D pin).
• SPI Notes: Requires 3.3V power supply.
• I2C Advantages: Plug-and-play, easy to use.

API Description

• Object Initialization: DFRobot_BME68x_I2C bme(0x77); (0x77 = default I2C address).
• Sensor Initialization: begin(); (returns 0 on success).
• Data Conversion: startConvert(); (triggers sensor to take measurements).
• Read Data: update(); (reads non-IAQ sensor data).
• IAQ Support: supportIAQ(); (enables IAQ functionality).
• IAQ Data Update: iaqUpdate(); (reads IAQ and sensor data).
• IAQ Readiness Check: isIAQReady(); (returns 1 if IAQ data is available).
• Temperature: readTemperature(); (returns °C with 2 decimal places).
• Pressure: readPressure(); (returns Pa with 2 decimal places).
• Humidity: readHumidity(); (returns %rh with 2 decimal places).
• Gas Resistance: readGasResistance(); (returns ohms with 2 decimal places).
• Altitude: readAltitude(); (returns meters with 2 decimal places).
• Sea Level Pressure: readSeaLevel(float altitude); (calculates sea-level pressure from a known altitude).
• Calibrated Altitude: readCalibratedAltitude(float seaLevel); (calculates altitude from sea-level pressure).
• Heating Layer Control: setGasHeater(uint16_t heaterTemp, uint16_t heaterTime); (sets target temperature: 200~400°C, duration: ms).

Principle

The BME688 is a highly integrated MEMS (Micro-Electro-Mechanical Systems) environmental sensor that measures temperature, humidity, barometric pressure, and VOCs (volatile organic compounds). Key improvements over the BME680 include:

• Temperature Accuracy: Enhanced IC design to reduce external heat interference.
• Heating Layer: A bottom-mounted heating layer that minimizes ambient temperature effects on VOC measurements. Users can adjust the heating temperature to analyze specific gas responses for AI-driven applications.
• Drop-in Compatibility: Software/hardware compatible with BME680, enabling easy replacement in existing systems.

Other Supplementary Information

Compatible Test

IAQ(Indoor Air Quality) Comparison Table