mirror of
https://github.com/dz0ny/meshcore-sar.git
synced 2026-08-11 16:30:28 +00:00
feat: MeshCore SAR - Flutter BLE mesh radio companion app
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
Janez T
321
lib/services/cayenne_lpp_parser.dart
Normal file
321
lib/services/cayenne_lpp_parser.dart
Normal file
@@ -0,0 +1,321 @@
|
||||
import 'package:flutter/foundation.dart';
|
||||
import 'package:latlong2/latlong.dart';
|
||||
import '../models/contact_telemetry.dart';
|
||||
import 'buffer_reader.dart';
|
||||
import 'meshcore_constants.dart';
|
||||
|
||||
/// Cayenne LPP (Low Power Payload) data parser
|
||||
/// Used for decoding telemetry sensor data from MeshCore devices
|
||||
class CayenneLppParser {
|
||||
/// Parse Cayenne LPP data into ContactTelemetry
|
||||
static ContactTelemetry parse(Uint8List data) {
|
||||
debugPrint(' [CayenneLPP] Parsing LPP data...');
|
||||
debugPrint(' Data length: ${data.length} bytes');
|
||||
debugPrint(
|
||||
' Data (hex): ${data.map((b) => b.toRadixString(16).padLeft(2, '0')).join(' ')}',
|
||||
);
|
||||
|
||||
final reader = BufferReader(data);
|
||||
|
||||
LatLng? gpsLocation;
|
||||
double? batteryPercentage;
|
||||
double? batteryMilliVolts;
|
||||
double? temperature;
|
||||
double? humidity;
|
||||
double? pressure;
|
||||
final extraSensorData = <String, dynamic>{};
|
||||
|
||||
int fieldCount = 0;
|
||||
while (reader.hasRemaining) {
|
||||
try {
|
||||
fieldCount++;
|
||||
debugPrint(
|
||||
' [Field $fieldCount] Position: ${data.length - reader.remainingBytesCount}',
|
||||
);
|
||||
|
||||
final channel = reader.readByte();
|
||||
debugPrint(' Channel: $channel');
|
||||
|
||||
final type = reader.readByte();
|
||||
debugPrint(
|
||||
' Type: $type (0x${type.toRadixString(16).padLeft(2, '0')})',
|
||||
);
|
||||
|
||||
switch (type) {
|
||||
case MeshCoreConstants.lppDigitalInput:
|
||||
final value = reader.readByte();
|
||||
debugPrint(' Digital Input: $value');
|
||||
extraSensorData['digital_input_$channel'] = value;
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppDigitalOutput:
|
||||
final value = reader.readByte();
|
||||
debugPrint(' Digital Output: $value');
|
||||
extraSensorData['digital_output_$channel'] = value;
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppAnalogInput:
|
||||
final rawValue = reader.readInt16BE();
|
||||
final value = rawValue / 100.0;
|
||||
debugPrint(' Analog Input (raw): $rawValue');
|
||||
debugPrint(' Analog Input (volts): ${value}V');
|
||||
extraSensorData['analog_input_$channel'] = value;
|
||||
// If this is a battery reading
|
||||
if (channel == 0 || channel == 1) {
|
||||
batteryMilliVolts = value * 1000;
|
||||
batteryPercentage = _calculateBatteryPercentage(value);
|
||||
debugPrint(
|
||||
' → Battery: ${batteryPercentage.toStringAsFixed(1)}% (${batteryMilliVolts.toStringAsFixed(0)}mV)',
|
||||
);
|
||||
}
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppAnalogOutput:
|
||||
final rawValue = reader.readInt16BE();
|
||||
final value = rawValue / 100.0;
|
||||
debugPrint(' Analog Output (raw): $rawValue');
|
||||
debugPrint(' Analog Output (volts): ${value}V');
|
||||
extraSensorData['analog_output_$channel'] = value;
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppIlluminanceSensor:
|
||||
final value = reader.readUInt16BE();
|
||||
debugPrint(' Illuminance: $value lux');
|
||||
extraSensorData['illuminance_$channel'] = value;
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppPresenceSensor:
|
||||
final value = reader.readByte();
|
||||
debugPrint(' Presence: $value');
|
||||
extraSensorData['presence_$channel'] = value;
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppTemperatureSensor:
|
||||
final rawValue = reader.readInt16BE();
|
||||
temperature = rawValue / 10.0;
|
||||
debugPrint(' Temperature (raw): $rawValue');
|
||||
debugPrint(
|
||||
' Temperature: ${temperature.toStringAsFixed(1)}°C',
|
||||
);
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppHumiditySensor:
|
||||
final rawValue = reader.readByte();
|
||||
humidity = rawValue / 2.0;
|
||||
debugPrint(' Humidity (raw): $rawValue');
|
||||
debugPrint(' Humidity: ${humidity.toStringAsFixed(1)}%');
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppAccelerometer:
|
||||
final x = reader.readInt16BE() / 1000.0;
|
||||
final y = reader.readInt16BE() / 1000.0;
|
||||
final z = reader.readInt16BE() / 1000.0;
|
||||
debugPrint(' Accelerometer: x=$x, y=$y, z=$z');
|
||||
extraSensorData['accelerometer_$channel'] = {
|
||||
'x': x,
|
||||
'y': y,
|
||||
'z': z,
|
||||
};
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppBarometer:
|
||||
final rawValue = reader.readUInt16BE();
|
||||
pressure = rawValue / 10.0;
|
||||
debugPrint(' Barometer (raw): $rawValue');
|
||||
debugPrint(' Barometer: ${pressure.toStringAsFixed(1)} hPa');
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppVoltageSensor:
|
||||
final rawValue = reader.readUInt16BE();
|
||||
final value = rawValue / 100.0;
|
||||
debugPrint(' Voltage (raw): $rawValue');
|
||||
debugPrint(' Voltage: ${value}V');
|
||||
// Treat voltage sensor as battery reading
|
||||
batteryMilliVolts = value * 1000;
|
||||
batteryPercentage = _calculateBatteryPercentage(value);
|
||||
debugPrint(
|
||||
' → Battery: ${batteryPercentage.toStringAsFixed(1)}% (${batteryMilliVolts.toStringAsFixed(0)}mV)',
|
||||
);
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppGyrometer:
|
||||
final x = reader.readInt16BE() / 100.0;
|
||||
final y = reader.readInt16BE() / 100.0;
|
||||
final z = reader.readInt16BE() / 100.0;
|
||||
debugPrint(' Gyrometer: x=$x, y=$y, z=$z');
|
||||
extraSensorData['gyrometer_$channel'] = {'x': x, 'y': y, 'z': z};
|
||||
break;
|
||||
|
||||
case MeshCoreConstants.lppGps:
|
||||
// Standard Cayenne LPP GPS format (type 0x88):
|
||||
// - Latitude: 3 bytes, signed 24-bit, big-endian, × 10000
|
||||
// - Longitude: 3 bytes, signed 24-bit, big-endian, × 10000
|
||||
// - Altitude: 3 bytes, signed 24-bit, big-endian, × 100
|
||||
// Total: 9 bytes (not the 12 bytes used in MeshCore advertisements!)
|
||||
|
||||
// Read 3-byte signed big-endian integers
|
||||
final latBytes = reader.readBytes(3);
|
||||
int rawLat = (latBytes[0] << 16) | (latBytes[1] << 8) | latBytes[2];
|
||||
// Sign extend from 24-bit to 32-bit
|
||||
if (rawLat > 0x7FFFFF) rawLat = rawLat - 0x1000000;
|
||||
|
||||
final lonBytes = reader.readBytes(3);
|
||||
int rawLon = (lonBytes[0] << 16) | (lonBytes[1] << 8) | lonBytes[2];
|
||||
if (rawLon > 0x7FFFFF) rawLon = rawLon - 0x1000000;
|
||||
|
||||
final altBytes = reader.readBytes(3);
|
||||
int rawAlt = (altBytes[0] << 16) | (altBytes[1] << 8) | altBytes[2];
|
||||
if (rawAlt > 0x7FFFFF) rawAlt = rawAlt - 0x1000000;
|
||||
|
||||
// Decode: divide by scaling factors
|
||||
final lat = rawLat / 10000.0;
|
||||
final lon = rawLon / 10000.0;
|
||||
final alt = rawAlt / 100.0;
|
||||
|
||||
debugPrint(
|
||||
' GPS Location (raw 24-bit BE): lat=$rawLat (0x${rawLat.toRadixString(16).padLeft(6, '0')}), lon=$rawLon (0x${rawLon.toRadixString(16).padLeft(6, '0')}), alt=$rawAlt (0x${rawAlt.toRadixString(16).padLeft(6, '0')})',
|
||||
);
|
||||
debugPrint(
|
||||
' GPS Location (decoded): ${lat.toStringAsFixed(6)}°, ${lon.toStringAsFixed(6)}°, altitude=${alt.toStringAsFixed(2)}m',
|
||||
);
|
||||
|
||||
// Validate coordinates are in valid range
|
||||
if (lat < -90.0 || lat > 90.0) {
|
||||
debugPrint(' ⚠️ WARNING: Latitude out of range: $lat°');
|
||||
}
|
||||
if (lon < -180.0 || lon > 180.0) {
|
||||
debugPrint(' ⚠️ WARNING: Longitude out of range: $lon°');
|
||||
}
|
||||
|
||||
gpsLocation = LatLng(lat, lon);
|
||||
extraSensorData['altitude_$channel'] = alt;
|
||||
break;
|
||||
|
||||
default:
|
||||
debugPrint(
|
||||
' ⚠️ Unknown type, skipping remaining ${reader.remainingBytesCount} bytes',
|
||||
);
|
||||
// Unknown type, skip remaining to avoid parsing errors
|
||||
reader.skip(reader.remainingBytesCount);
|
||||
break;
|
||||
}
|
||||
} catch (e) {
|
||||
debugPrint(' ❌ Parsing error: $e');
|
||||
// If we encounter a parsing error, break and return what we have
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
debugPrint(' Parsed $fieldCount fields');
|
||||
debugPrint(' ✅ [CayenneLPP] Parsing complete');
|
||||
debugPrint(
|
||||
' GPS: ${gpsLocation != null ? '${gpsLocation.latitude}°, ${gpsLocation.longitude}°' : 'none'}',
|
||||
);
|
||||
debugPrint(
|
||||
' Battery: ${batteryPercentage != null ? '${batteryPercentage.toStringAsFixed(1)}%' : 'none'}',
|
||||
);
|
||||
debugPrint(
|
||||
' Temperature: ${temperature != null ? '${temperature.toStringAsFixed(1)}°C' : 'none'}',
|
||||
);
|
||||
|
||||
// IMPORTANT: Cayenne LPP format does NOT include a timestamp field.
|
||||
// We use DateTime.now() as the timestamp, which represents when the data
|
||||
// was RECEIVED/PARSED by the app, NOT when it was collected by the device.
|
||||
//
|
||||
// This means:
|
||||
// - If the device sends cached/old telemetry data, the timestamp will still
|
||||
// show as "recent" (a few seconds ago) because it was just received
|
||||
// - The actual age of the telemetry data cannot be determined from the LPP format
|
||||
// - Devices may cache telemetry for hours and send it later when requested
|
||||
final parseTimestamp = DateTime.now();
|
||||
debugPrint(
|
||||
' Timestamp: $parseTimestamp (parse time, NOT device collection time)',
|
||||
);
|
||||
|
||||
return ContactTelemetry(
|
||||
gpsLocation: gpsLocation,
|
||||
batteryPercentage: batteryPercentage,
|
||||
batteryMilliVolts: batteryMilliVolts,
|
||||
temperature: temperature,
|
||||
humidity: humidity,
|
||||
pressure: pressure,
|
||||
timestamp: parseTimestamp,
|
||||
extraSensorData: extraSensorData.isNotEmpty ? extraSensorData : null,
|
||||
);
|
||||
}
|
||||
|
||||
/// Calculate battery percentage from voltage (V)
|
||||
static double _calculateBatteryPercentage(double voltage) {
|
||||
// Standard lithium battery curve: 3.0V = 0%, 4.2V = 100%
|
||||
if (voltage <= 3.0) return 0.0;
|
||||
if (voltage >= 4.2) return 100.0;
|
||||
return ((voltage - 3.0) / 1.2) * 100.0;
|
||||
}
|
||||
|
||||
/// Create Cayenne LPP data for GPS location
|
||||
/// Standard Cayenne LPP GPS format (type 0x88):
|
||||
/// - Latitude: 3 bytes, signed 24-bit, big-endian, × 10000
|
||||
/// - Longitude: 3 bytes, signed 24-bit, big-endian, × 10000
|
||||
/// - Altitude: 3 bytes, signed 24-bit, big-endian, × 100
|
||||
static Uint8List createGpsData({
|
||||
required double latitude,
|
||||
required double longitude,
|
||||
double altitude = 0.0,
|
||||
int channel = 0,
|
||||
}) {
|
||||
final buffer = <int>[];
|
||||
|
||||
buffer.add(channel);
|
||||
buffer.add(MeshCoreConstants.lppGps);
|
||||
|
||||
// Latitude (signed 24-bit BE, 3 bytes, 0.0001° precision)
|
||||
int lat = (latitude * 10000).round();
|
||||
// Handle negative values (two's complement for 24-bit)
|
||||
if (lat < 0) lat = lat + 0x1000000;
|
||||
buffer.add((lat >> 16) & 0xFF); // Byte 0 (MSB)
|
||||
buffer.add((lat >> 8) & 0xFF); // Byte 1
|
||||
buffer.add(lat & 0xFF); // Byte 2 (LSB)
|
||||
|
||||
// Longitude (signed 24-bit BE, 3 bytes, 0.0001° precision)
|
||||
int lon = (longitude * 10000).round();
|
||||
if (lon < 0) lon = lon + 0x1000000;
|
||||
buffer.add((lon >> 16) & 0xFF); // Byte 0 (MSB)
|
||||
buffer.add((lon >> 8) & 0xFF); // Byte 1
|
||||
buffer.add(lon & 0xFF); // Byte 2 (LSB)
|
||||
|
||||
// Altitude (signed 24-bit BE, 3 bytes, 0.01m precision)
|
||||
int alt = (altitude * 100).round();
|
||||
if (alt < 0) alt = alt + 0x1000000;
|
||||
buffer.add((alt >> 16) & 0xFF); // Byte 0 (MSB)
|
||||
buffer.add((alt >> 8) & 0xFF); // Byte 1
|
||||
buffer.add(alt & 0xFF); // Byte 2 (LSB)
|
||||
|
||||
return Uint8List.fromList(buffer);
|
||||
}
|
||||
|
||||
/// Create Cayenne LPP data for temperature
|
||||
static Uint8List createTemperatureData(double celsius, {int channel = 0}) {
|
||||
final buffer = <int>[];
|
||||
buffer.add(channel);
|
||||
buffer.add(MeshCoreConstants.lppTemperatureSensor);
|
||||
|
||||
final temp = (celsius * 10).round();
|
||||
buffer.add((temp >> 8) & 0xFF);
|
||||
buffer.add(temp & 0xFF);
|
||||
|
||||
return Uint8List.fromList(buffer);
|
||||
}
|
||||
|
||||
/// Create Cayenne LPP data for battery voltage
|
||||
static Uint8List createBatteryData(double voltage, {int channel = 0}) {
|
||||
final buffer = <int>[];
|
||||
buffer.add(channel);
|
||||
buffer.add(MeshCoreConstants.lppAnalogInput);
|
||||
|
||||
final volts = (voltage * 100).round();
|
||||
buffer.add((volts >> 8) & 0xFF);
|
||||
buffer.add(volts & 0xFF);
|
||||
|
||||
return Uint8List.fromList(buffer);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user