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If a PROFINET diagnosis is reported to the PROFINET IO Device protocol stack running on the NIC52-RE via the packet PNS_IF_ADD_CHANNEL_DIAG_REQ, the STA-LED remains on until a hardware reset occurs.
This behavior is contrary to that of the NIC50-RE where the STA-LED will not react to a PNS_IF_ADD_CHANNEL_DIAG_REQ packet.
The behavior of the NIC52-RE is intended and correct. Other Hilscher PROFINET Devices operate in the same way.
Sending an appropriate PNS_IF_REMOVE_DIAG_REQ packet will switch off the STA-LED.
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