Russian Qt Forum

void MainWindow::serialPortCtrl()
{
    if(ui->pushButton->isChecked())
    {
        QThread* thread_device = new QThread;
        CModbus* newdevice     = new CModbus;
        
        newdevice->moveToThread(thread_device);
        newdevice->m_device.moveToThread(thread_device);
        
        connect(thread_device, SIGNAL(started()), newdevice, SLOT(connectModbusDevice()));
        connect(newdevice, &CModbus::disconnectDeviceFinish, thread_device, &QThread::quit);
        connect(newdevice, &CModbus::disconnectDeviceFinish, this, &MainWindow::disconnectDevice);
        connect(thread_device, &QThread::finished, newdevice, &CModbus::deleteLater);
        connect(newdevice, &CModbus::connectDeviceOk, this, &MainWindow::connectStateOk);
        connect(newdevice, &CModbus::errorDevice, this, &MainWindow::errorDevice);
        connect(this, &MainWindow::signalDisconnectDevice, newdevice, &CModbus::disconnectModbusDevice);
        connect(ui->pushButtonSend, &QPushButton::clicked, newdevice, &CModbus::modbusRequest);
        
        thread_device->start();
    }
    else
    {
        emit signalDisconnectDevice();
    }
}

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

void CModbus::modbusRequest()
{
    QModbusDataUnit unit(QModbusDataUnit::InputRegisters, 64, 10);
    
    QModbusReply* reply;
    
    reply = m_device.sendReadRequest(unit, 0x01);
    
    if(reply)
    {
        if(!reply->isFinished())
        {
            connect(reply, &QModbusReply::finished, this, &CModbus::modbusReadReady);
        }
        else
        {
            delete reply;
        }
    }
    else
        emit errorDevice(m_device.errorString());
}