I have created the following class in flutter that uses hid_tool package:

import 'dart:async';
import 'package:hid_tool/hid_tool.dart';

class ShiftDispenser {
  late HidDevice _device;
  late StreamSubscription? _subscription;
  final Function(String) onDataReceived;
  final Function(String)? onError;

  bool _isConnected = false;

  ShiftDispenser({required this.onDataReceived, this.onError});

  Future connect() async {
    try {
      final devices = await Hid.getDevices();
      _device = devices.isNotEmpty
          ? devices.first
          : throw Exception('No HID device found');

      await _device.open();
      _isConnected = true;
      await _readData();
      return true;
    } catch (e) {
      onError?.call('Failed to connect: $e');
      return false;
    }
  }

  Future _readData() async {
    try {
      if (!_device.isOpen) {
        throw Exception('Failed to open HID device');
      }

      _subscription = _device.inputStream().listen(
        (byte) {
          print('Buffer: ${String.fromCharCode(byte)}');
        },
        onError: (Object e) => print('Stream error: $e'),
        onDone: () => print('Stream closed'),
      );
    } catch (e) {
      onError?.call('Error reading data: $e');
    }
  }

  Future disconnect() async {
    if (_subscription != null) {
      await _subscription!.cancel();
      _subscription = null;
    }

    if (_isConnected) {
      await _device.close();
      _isConnected = false;
    }
  }

  bool get isConnected => _isConnected;
}

To get the device I call ´connect´ method. This method also start listening for data comming from an HID device. That device i actually a QR code reader.

For testing purposes, I created a QR code that contains only a text with this content: "6".

When I run the app in a real device (an Android tablet) and read that QR, what is actually read are:

• two 0x00

• one 0x35

• twenty nine 0x00

What I expected to read is only a 0x36.

What is wrong with this?

Thanks