Extracting BBC Micro:bit accelerometer data using Flutter Blue

extract.dart

/// This gist assumes that Flutter Blue (https://github.com/pauldemarco/flutter_blue) is used to connect to a BBC Micro:bit 
/// and is listening to the [device.onValueChanged] for the correct characteristic ("E95DCA4B-251D-470A-A062FA1922DFA9A8")
///
/// this will be something similar to
///
/// device.onValueChanged( (accChar).listen( (value){ convertRawData(value)}));
///
/// the 'raw' listen value is a List<int> of length 6 this needs to be converted into the X,Y and Z values from the 
/// accelerometer and is done with the function below
///
/// The result is a List<double> with 3 values for X, Y & Z with values approx -1 to +1


convertRawData(data) {

  Uint8List reading = Uint8List.fromList(value);
  ByteData buffer = ByteData.view(reading.buffer);
  double x = buffer.getInt16(0, Endian.little)/1000;
  double y = buffer.getInt16(2, Endian.little)/1000;
  double z = buffer.getInt16(4, Endian.little)/1000;

  return [x, y, z];
  
}