correct disconnect

Src/mainwindow.cpp

@@ -154,19 +154,21 @@ void MainWindows::onStateChanged(QModbusDevice::State state) {
 
 void MainWindows::onConnectButtonClicked() {
     if (!m_connected) {
+        m_disconnectRequested = false;
         if (!m_modbusClient->connectDevice()) {
             QMessageBox::critical(this, tr("Connection Error"),
                                 tr("Could not connect to the Modbus device!"));
         }
         // Start connection timeout timer
         QTimer::singleShot(m_connectTimeout, this, [this]() {
-            if (!m_connected) {
+            if (!m_connected && !m_disconnectRequested) {
                 m_modbusClient->disconnectDevice();
                 QMessageBox::warning(this, tr("Connection Timeout"),
                                    tr("Connection attempt timed out!"));
             }
         });
     } else {
+        m_disconnectRequested = true;
         m_modbusClient->disconnectDevice();
     }
 }