FS-8700-16 BACnet PTP Serial Driver Manual
Page 23 of 32
FieldServer Technologies
1991 Tarob Court Milpitas, California 95035 USA
Web
: www.fieldserver.com
Tel
: (408) 262-2299
Fax
: (408) 262-9042
Toll Free
: (888) 509-1970
Appendix A.6.1.
Notes on COV configura tion:
COV functionality is not enabled by default for MSTP. The Node_Option parameter can be configured to
enable or disable COV. An example configuration is presented in Appendix A.6.5. Systems using
BACnet/IP or BACnet/Ethernet to BACnet/MSTP routers may not function reliably if COV functionality is
enabled as the router will make the MSTP device appear as a BACnet/IP or BACnet/Ethernet device, which
could lead the BACnet Workstation to expect unrealistic throughput performance when subscribing to
multiple points. It is recommended only to enable COV functionality on MSTP systems if the Client device
communicates directly via MSTP, or if the user knows that the throughput issue will not arise..
COV functionality (SubscribeCOV service) only applies to the Present_Value and Status_Flags properties of
BACnet Objects - the SubscribeCOVProperty service is not supported by the FieldServer.
For analog Server Map Descriptors the user may optionally configure a COV_Increment value to adjust the
reporting threshold. If it is not set the COV_Increment defaults to zero.
COV Notifications are generated for all data objects for which a remote client has issued a SubscribeCOV-
Request. The SubscribeCOV-Request regulates whether Notifications are Confirmed or Unconfirmed. The
remote Client may also write the COV_Increment property in order to control the deadband for changes
in analog values. The COV_Increment property can be initialized via the configuration file by setting the
COV_Increment Map Descriptor Property. The value set by the configuration is an initial value that is
loaded on startup. It would be replaced by any new value written by the Client
COV is not available on the ProtoCessor
Appendix A.6.2.
Notes on Intrinsic Reporting configuration:
Intrinsic Reporting is managed by Notification Class objects. At least one Notification Class object must be
configured for Intrinsic Reporting to work.
Each Data_Object that is to be monitored by Intrinsic Reporting must be linked to a Notification Class
object via the Notification_Class Map Descriptor Property. For analog points alarm limits must be set up,
and for binary points, the Input_Alarm_State (specifying which binary value (0 or 1) to regard as the Alarm
state) must be set up.
The Notification_Class object contains properties that allow a client workstation to modify rules governing
event reporting, such as event_type, days of week, start and end times etc.
The RecipientLists are non-volatile, and subscriptions must be renewed on system restart.
