MicroPython Library

The Soldered ElectrochemicalGasSensor MicroPython Library is ElectrochemicalGasSensor.py, with lmp91000.py and ads1115.py as helpers. Create an ElectrochemicalGasSensor with a gas preset and your I2C object, call begin(), then read ppm or ppb. SENSOR_NH3 is the module's preset for this board's ammonia cell.

Connect the board over Qwiic. Out of the box the board answers on address 0x30, and its ADDRESS switch moves it up to 0x37. When adc_addr is from 0x30 to 0x37, the module talks to the board through its ATtiny404 bridge. With any other adc_addr it talks to the board's ADS1115 directly, on the header's SDA2/SCL2 pins, which the Qwiic connectors do not reach: the examples that do this say on their pages how to wire the header instead.

Not installed yet? Follow Quick Start before using the functionality pages.

Public sourceSoldered ElectrochemicalGasSensor MicroPython LibraryMicroPython module with sensor presets, ppm and ppb readings, averaging and zero calibration.Pinned reference: commit 623e1e6

Functionality

Each page starts with one verified module example and explains every function the example uses to get that result.

MicroPython exampleRead the gas concentrationStart the board through its bridge and print the concentration in ppm every 2.5 seconds.electrochemical-bridgeBoard.pyMicroPython exampleAveraged measurementAverage several readings for a steadier value.electrochemical-averagedMeasurement.pyMicroPython exampleCalibrate the zero pointSet the offset that makes clean air read zero.electrochemical-calibrateSensor.pyMicroPython exampleCustom front end configurationBuild your own SensorConfig and tune the LMP91000 settings.electrochemical-customConfig.pyMicroPython exampleSingle sensor readingPrint the concentration in ppb every 2.5 seconds.electrochemical-singleSensor.pyMicroPython exampleTwo sensors on one busCreate two sensor objects on one I2C bus, each with its own address, and print both readings.electrochemical-twoSensors.py