Microbit_Magnetometer

The Microbit_Magnetometer provides the ability to configure the BBC micro:bit’s on-board magnetometer and receive one or more magnetometer samples via the appropriate methods.

Properties

• BluetoothDevice – The BluetoothLE component connected to the micro:bit device (setter).

Methods

• ReadMagnetometerBearing – Read a single bearing sample from the micro:bit. On successful read, the MagnetometerBearingReceived event will be run.

• ReadMagnetometerData – Read a single sample of magnetometer data from the micro:bit. On successful read, the MagnetometerDataReceived event will be run.

• ReadMagnetometerPeriod – Read the current report rate for the micro:bit magnetometer. After the period is read, it will be received by the MagnetometerPeriodReceived event.

• RequestMagnetometerBearingUpdates – Request notifications of changes in the micro:bit’s bearing. Changes in the bearing will be reported at a rate determined by the last period value set by a call to WriteMagnetometerPeriod. Bearing data will be reported through the MagnetometerBearingReceived event.

• RequestMagnetometerDataUpdates – Request notifications of changes in the micro:bit’s magnetometer. Changes in the magnetometer will be reported at a rate determined by the last period value set by a call to WriteMagnetometerPeriod. Magnetometer data will be reported through the MagnetometerDataReceived event.

• StopMagnetometerBearingUpdates – Stop receiving updates from the micro:bit’s magnetometer. Note that there may be pending messages from the device that will still be reported through the MagnetometerBearingReceived event.

• StopMagnetometerDataUpdates – Stop receiving updates from the micro:bit’s magnetometer. Note that there may be pending messages from the device that will still be reported through the MagnetometerDataReceived event.

• WriteMagnetometerPeriod – Use the WriteMagnetometerPeriod method to change how frequently the micro:bit sends magnetometer data to App Inventor. The period is measured in milliseconds. According to the micro:bit specification, valid values are 1, 2, 5, 10, 20, 80, 160 and 640 milliseconds.

  Parameters:

  • Magnetometer_Period (number) — The new magnetometer reporting period, in milliseconds.

Events

• MagnetometerBearingReceived – The MagnetometerBearingReceived event is run whenever bearing samples are received from the micro:bit. This is usually a result of performing a read or request operation. The bearing value is reported as degrees relative to North.

  Parameters:

  • bearing_value (number) — The bearing from North, in degrees.

• MagnetometerDataReceived – The MagnetometerDataReceived event is run whenever magnetometer samples are received from the micro:bit. This is usually a result of performing a read or request operation. The X, Y, and Z values are in milli-teslas, and so should be scaled by 1/1000.

  Parameters:

  • Magnetometer_X (number) — The X value of the magnetometer, in milliT.
  • Magnetometer_Y (number) — The Y value of the magnetometer, in milliT.
  • Magnetometer_Z (number) — The Z value of the magnetometer, in milliT.

• MagnetometerPeriodReceived – The MagnetometerPeriodReceived event is run after the micro:bit’s magnetometer period is read from the device.

  Parameters:

  • Magnetometer_Period (number) — The current reporting interval for the micro:bit’s magnetometer, in milliseconds.

• WroteMagnetometerPeriod – The WroteMagnetometerPeriod event is run after the micro:bit reports its period as requested by an earlier call to the ReadAccelerometerPeriod method.

  Parameters:

  • Magnetometer_Period (number) — The reporting periodf or the micro:bit’s magnetometer, in milliseconds.