java.lang.InterruptedException on close invocation

[camillobucciarelli]

When I try to close connection with port.close(); I get the following error in console:

D/UsbDeviceConnectionJNI(28094): close
W/System.err(28094): java.lang.InterruptedException
W/System.err(28094): 	at java.lang.Object.wait(Native Method)
W/System.err(28094): 	at java.lang.Object.wait(Object.java:386)
W/System.err(28094): 	at java.lang.Object.wait(Object.java:524)
W/System.err(28094): 	at com.felhr.usbserial.SerialBuffer$SynchronizedBuffer.get(SerialBuffer.java:117)
W/System.err(28094): 	at com.felhr.usbserial.SerialBuffer.getWriteBuffer(SerialBuffer.java:72)
W/System.err(28094): 	at com.felhr.usbserial.UsbSerialDevice$WriteThread.doRun(UsbSerialDevice.java:402)
W/System.err(28094): 	at com.felhr.usbserial.AbstractWorkerThread.run(AbstractWorkerThread.java:21)

there is something that I'm doing wrong?

Thank you

[rockerer]

Hi,
can you provde a small code example, how you use the lib? Some information about the used hardware is helpful, too.
Thanks

[cwangfr]

i have same problem
android-arm • Android 9 (API 28)
CH34xSerialDevice
Flutter 3.16.9
Dart version 3.2.6

my code is like this

final port = usbDevice.create();
if (await port.open()) {
      debugPrint("connection success");
      port.setPortParameters(
          9600, UsbPort.DATABITS_8, UsbPort.STOPBITS_1, UsbPort.PARITY_NONE);
      debugPrint("port parameter: ${port.toString()}");
  final anser = <int>[];
  Timer? timeoutTimer;
  bool success = false;
  final completer = Completer<void>();
  late final StreamSubscription<Uint8List> sub;
  sub = port.inputStream!.listen((event) {
    anser.addAll(event);
    debugPrint("event: $event, anser: $anser");
    if (response.isEmpty ||
        (response.isNotEmpty && anser.containsAll(response))) {
      debugPrint("success");
      sub.cancel();
      success = true;
      if (timeoutTimer != null) timeoutTimer.cancel();
      completer.complete();
    }
  });
  await port.write(dataSend);

  timeoutTimer = Timer(Duration(milliseconds: timeOut), () {
    if (!success) {
      debugPrint('Timeout: Did not find the required data within 3 seconds');
      sub.cancel(); //cancel Stream
      completer.complete(); // finish Completer
    }
  });
  await completer.future;
// all task finished.
port.close(); // exception is here
}

[rockerer]

Does your android device work with the CH34xSerialDevice when using the example app? What does the error look like?

[zyq9613]

Is it resolved? I also encountered this mistake.

[zyq9613]

`Future _readResponseWithTimeout(UsbPort port) async {
print('1@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@');
final completer = Completer();
port.inputStream?.listen((Uint8List data) {
if (data.isEmpty) {
if (!completer.isCompleted) {
completer.complete("");
}
}
print('received: $data');
String hexString =
data.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();

  if (!completer.isCompleted) {
    completer.complete(hexString.toUpperCase());
  }
});
// 设置超时
Future.delayed(const Duration(milliseconds: timeoutMs), () async {
  if (!completer.isCompleted) {
    completer.complete("");
  }
});
return completer.future;

}

Uint8List hexStringToUint8List(String hexString) {
// 去除空格并将字符串转换为大写
hexString = hexString.replaceAll(' ', '').toUpperCase();
// 创建一个空的列表来存储转换后的字节
List byteList = [];
// 遍历每两个字符，将其转换为十六进制字节
for (int i = 0; i < hexString.length; i += 2) {
String hexByte = hexString.substring(i, i + 2); // 取出每两位字符
byteList.add(int.parse(hexByte, radix: 16)); // 将两位字符转换为十六进制字节
}
print(Uint8List.fromList(byteList));
// 返回对应的 Uint8List
return Uint8List.fromList(byteList);
}

void initialize({String? portName}) async {
if (_serialPort != null) return;
UsbPort? port;
try {
List devices = await UsbSerial.listDevices();
if (devices.isEmpty) {
print("没有可用的USB设备");
return;
}
Uint8List byteArray = hexStringToUint8List(hexString);
for (UsbDevice device in devices) {
// 创建端口
port = await device.create();
bool? openResult = await port?.open();
if (openResult == null || !openResult) {
print("打开串口失败: ${device.toString()}");
continue;
}
print('当前的串口: ${port.toString()}');
await port!.setDTR(true);
await port.setRTS(true);
port.setPortParameters(115200, UsbPort.DATABITS_8, UsbPort.STOPBITS_1,
UsbPort.PARITY_NONE);
port.setFlowControl(UsbPort.FLOW_CONTROL_OFF);
// 发送消息
await port.write(byteArray);
// 获取返回信息
String data = await _readResponseWithTimeout(port);
print("Received data: $data");
// 当前关闭的时候会报错，等官方修复，不影响其他操作
await port.close();
if (data.contains('FE')) {
_serialPort = port;
return;
}
}
} catch (e) {
print("初始化失败: $e");
} finally {}
}`