toPacket method
toPacket returns the packet in the format of Layrz Protocol v3.
Implementation
@override
String toPacket() {
String payload = '${(timestamp.millisecondsSinceEpoch / 1000).round()};';
payload += '$tripId;';
payload += '${distanceTraveled.toStringAsFixed(3)};';
payload += '${maxSpeed.toStringAsFixed(3)};';
payload += '${duration.inSeconds};';
String crc = calculateCrc(payload.codeUnits).toRadixString(16).padLeft(4, '0').toUpperCase();
return '<Te>$payload$crc</Te>';
}