Commanding via the PLC

The PLC can control the upload start or trigger it itself via the control unit (CU) on the PLC interface (HLI). To do this, the PLC must enable the control unit using the enable_w signal.

Starting point – control unit enabled

Every request is forwarded to the HLI. The data item request_r is set to TRUE on the CU. It is then possible to determine in the PLC whether the upload process is started. A start requires setting command_w to TRUE. As soon as state_r reverts to FALSE, the PLC must set command_w to FALSE. This completes writing of the diagnosis data.

Starting point – control unit disabled

Every request commands the upload process directly, provided no other upload is active. The request command comes either via the NC command or via the CNC object.