According to the BACnet protocol documentation:

Indicates the most recent update time of the Access_Event property. This property shall update its value on each update of Access_Event. Update times of type Time or Date shall have X'FF' in each octet, and Sequence Number update times shall have the value 0 if no update has yet occurred.

Property accessEventTime of object accessPoint can be read and written using a single IOTag.

Text Parameters

Numeric Parameters

Tag Value

A Date, Integer, Null or String (Xml) value representing a timestamp in BACnet.

•A null value means the timestamp is empty/not set;

•A date/time value representing a precise date and time;

•An integer defining the timestamp sequence number;

•A character string containing an XML with a value of type <BACnetTimeStamp>.