Pysense

This chapter describes the various libraries which are designed for the Pysense board. This includes details about the various methods and classes available for each of the Pysense’s sensors.

3-Axis Accelerometer (LIS2HH12)

Pysense has a 3-Axis Accelerometer that provides outputs for acceleration as well as roll, pitch and yaw.

Constructors

class LIS2HH12(pysense = None, sda = 'P22', scl = 'P21')

Creates a LIS2HH12 object, that will return values for acceleration, roll, pitch and yaw. Constructor must be passed a Pysense or I2C object to successfully construct.

Methods

LIS2HH12.acceleration()

Read the acceleration from the LIS2HH12. Returns a tuple with the 3 values of acceleration (G).

LIS2HH12.roll()

Read the current roll from the LIS2HH12. Returns a float in degrees in the range -180 to 180.

LIS2HH12.pitch()

Read the current pitch from the LIS2HH12. Returns a float in degrees in the range -90 to 90. Once the board tilts beyond this range the values will repeat. This is due to a lack of yaw measurement, making it not possible to know the exact orientation of the board.

Digital Ambient Light Sensor (LTR-329ALS-01)

Pysense has a dual light sensor that provides outputs for external light levels in lux. See the datasheet for more information about the wavelengths of the two sensors.

Constructors

class LTR329ALS01(pysense = None, sda = 'P22', scl = 'P21', gain = ALS_GAIN_1X, integration = ALS_INT_100, rate = ALS_RATE_500)

Creates a LTR329ALS01 object, that will return values for light in lux. Constructor must be passed a Pysense or I2C object to successfully construct.

Methods

LTR329ALS01.light()

Read the light levels of both LTR329ALS01 sensors. Returns a tuple with two values for light levels in lux.

Arguments

The following arguments may be passed into the constructor.

• gain: ALS_GAIN_1X,ALS_GAIN_2X, ALS_GAIN_4X, ALS_GAIN_8X, ALS_GAIN_48X, ALS_GAIN_96X
• integration: ALS_INT_50, ALS_INT_100, ALS_INT_150, ALS_INT_200, ALS_INT_250, ALS_INT_300, ALS_INT_350, ALS_INT_400
• rate: ALS_RATE_50, ALS_RATE_100, ALS_RATE_200, ALS_RATE_500, ALS_RATE_1000, ALS_RATE_2000

Humidity and Temperature Sensor (SI7006A20)

Pysense has a Humidity and Temperature sensor that provides values of relative humidity and external temperature.

Constructors

class SI7006A20(pysense = None, sda = 'P22', scl = 'P21')

Creates a SI7006A20 object, that will return values for humidity (%) and temperature ('C). Constructor must be passed a Pysense or I2C object to successfully construct.

Methods

SI7006A20.humidity()

Read the relative humidity of the SI7006A20. Returns a float with the percentage relative humidity.

SI7006A20.temperature()

Read the external temperature of the SI7006A20. Returns a float with the temperature.

Barometric Pressure Sensor with Altimeter (MPL3115A2)

Pysense has a Barometric Pressure sensor that provides readings for pressure, altitude as well as an additional temperature sensor.

Constructors

class MPL3115A2(pysense = None, sda = 'P22', scl = 'P21', mode = PRESSURE)

Creates a MPL3115A2 object, that will return values for pressure (Pa), altitude (m) and temperature ('C). Constructor must be passed a Pysense or I2C object to successfully construct.

Methods

MPL3115A2.pressure()

Read the atmospheric pressure of the MPL3115A2. Returns a float with the pressure in (Pa).

MPL3115A2.altitude()

Read the altitude of the MPL3115A2. Returns a float with the altitude in (m).

MPL3115A2.temperature()

Read the temperature of the MPL3115A2. Returns a float with the temperature in ('C).

Arguments

The following arguments may be passed into the constructor.

• mode: PRESSURE, ALTITUDE