Siemens SIMATIC PN/BACnet LINK - State Model

Functions
4.2 State model
PN/BACnet LINK
Operating Instructions, 10/2017, A5E39895543-AA
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4.2
State model
The configuration made in HSP is transmitted to the PB/BACnet LINK in the startup phase of
the S7 controller. This configuration information is stored in the S7 controller and not in the
PN/BACnet LINK.
Controlling the server and client status
Client functionality
The data transfer is controlled via a control byte (Page 32) which is transmitted cyclically by
the S7 controller to the PN/BACnet LINK as part of the I/O data.
If the bit for controlling the client functionality is set to OFF, the I/O data is not transmitted
between the PN/BACnet LINK and the BACnet network. Transmission is only activated when
the control bit is set to ON.
Server functionality
The system status in the device object is controlled via a control byte (Page 32). The S7
controller also transmits this control byte cyclically as part of the I/O data to the PN/BACnet
LINK.
The control byte can contain the following values:
Value of control byte
Reaction
OPERATIONAL
• "Out_Of_Service" flags of all server objects are updated.
• "Out_of_Service" property can be written from outside in this
state.
NON_OPERATIONAL
• "Out_Of_Service" flags of all server objects are set to TRUE.
• "SubscribeCOV", "WriteProperty", "ReadProperty" on server
objects are rejected.
• Subscribers using the SubscribeCOV service are notified
(Notification).
OPERATIONAL_READ_ONLY
• "WriteProperty" is rejected.
• "ReadProperty"/"SubscribeCOV" are accepted.
• "Out_Of_Service" flags of all server objects are still updated.