SerialPort in a different Thread

J.Hilk

H everyone,

So I've written a class that handles the serialport and data-transfer via ModBus.

The idea was to move the class to an other thread and run the data exchange idependet from the UI.

Everything seemed to work, but a Qt::BlockingQueuedConnection resulted in a deadlock -> Obviously I did something wrong. So I reworked it to this:

class HauptDesign : public QMainWindow
{
    Q_OBJECT
    QThread modbusThread;
....
....
}

HauptDesign::HauptDesign(QWidget *parent) :
    QMainWindow(parent)
    ,ui(new Ui::HauptDesign)
{    
    ui->setupUi(this);

    qRegisterMetaType<QList<int> >();
    qRegisterMetaType<QModbusDevice::State>();
    modbusDevice    = new Modbus;
    modbusDevice->moveToThread(&modbusThread);

connect(modbusDevice, &Modbus::signalConnectionState, this, &HauptDesign::VerbindungConnection);
connect(modbusDevice, &Modbus::signalNewDataRegs, this, &HauptDesign::receiveModbusRegister);
...
connect(this, &HauptDesign::connectDevice, modbusDevice, &Modbus::connectDevice);

modbusThread.start();

It works, I can successfully exchange data, but my Debug screen is flooded with

QObject::killTimer: timers cannot be stopped from another thread

QObject::startTimer: timers cannot be started from another thread

messages.
I don't use Timers in that class, I have not even defined one in the' modbusDevice' class. QModbusClient obviously has a connection timeout what might cause this issue!?

I'm at a loss how to do this the correct way.
Any help is appreciated

J.Hilk

Never mind,

I had code in my the constructor of the to be threaded class, that caused the conflict...

connect(&modbusThread, &QThread::started, modbusDevice, &Modbus::setupClass);

fixed the issue.