title: RuntimeError: Not connected to CAN bus how to solve this one
body: <p>I am running this code on python to do the machine control through CANopen and CANbus but I am getting this error, please help me to solve this one. </p>
  
  <p>Traceback (most recent call last):</p>
  
  <pre><code>  File "FW_CANopen_main_V1.1.py", line 718, in &lt;module&gt;
      initialisation()
    File "FW_CANopen_main_V1.1.py", line 35, in initialisation
      set_parameter()                                         # Parameter der INI Datei an FU schreiben
    File "FW_CANopen_main_V1.1.py", line 49, in set_parameter
      node2.sdo[0x202C].raw = L_SPEED_default * 10    # POSITION_speed_Y2; Faktor:10
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\common.py", line 90, in raw
      self.data = self.od.encode_raw(value)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\common.py", line 42, in data
      self.set_data(data)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\sdo.py", line 265, in set_data
      self.sdo_node.download(self.index, self.subindex, data, force_segment)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\sdo.py", line 194, in download
      fp.close()
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\sdo.py", line 528, in write
      response = self.sdo_client.request_response(request)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\sdo.py", line 120, in request_response
      self.send_request(sdo_request)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\sdo.py", line 91, in send_request
      self.network.send_message(self.rx_cobid, request)
    File "C:\Program Files (x86)\Python37-32\lib\site-packages\canopen\network.py", line 170, in send_message
      raise RuntimeError("Not connected to CAN bus")
  RuntimeError: Not connected to CAN bus[
  
  </code></pre>