According to the BACnet protocol documentation:

Indicates the date and time of the last transition of the timer state. If a transition of the timer state has never occurred, then this property shall take on the unspecified datetime value.

Property updateTime of object credentialDataInput 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>.