feat: added dummy function to test the connection

grum/mainwin.py

@@ -51,6 +51,7 @@ class MainWindow(QMainWindow):
         rst.start()
         rst.server.register_function(self.new_plot)
         rst.server.register_function(self.append_data)
+        rst.server.register_function(self.ping)
 
         self.sig_make_new_plot.connect(self.on_make_new_plot)
 
@@ -75,6 +76,8 @@ class MainWindow(QMainWindow):
         else:
             item.set_alarm(True)
 
+    def ping(self):
+        return "pong"
 
     # Signal callbacks