Bacnet Ms/Tp Client - ICC XLTR-1000 Instruction Manual

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9.3.2 BACnet MS/TP Client

9.3.2.1 Overview
The gateway supports BACnet MS/TP client on both of its RS-485 ports. Some
notes of interest are:
• The gateway supports reading and writing the present value property of
BACnet objects in devices on the network.
• Requests are fully configurable through service objects.
• Supported BACnet objects include:
o
Analog Input
o Analog Output
o Analog Value
o Binary Input
o Binary Output
o Binary Value
• Supported baud rates include:
o
4800
o
9600
o
19200
o
38400
o
57600
o 76800
o 115200
• Static device binding is supported.
9.3.2.2 BACnet Service Objects
The BACnet MS/TP Client protocol uses service objects to describe what
services the gateway should perform. For each service object, the gateway will
continually read the present value of the defined BACnet object within the service
object from the designated device, storing the value(s) in the database (if the
read function is enabled). When data in the database changes where the BACnet
objects are mapped, a write request is generated to the designated device
notifying it of the changed present value(s) of the BACnet object(s) (if the write
function is enabled). For more information on configuring BACnet service objects,
refer to section 8.6.3.3.
9.3.2.3 Device Binding
Dynamic Device Binding
In order for a BACnet client to request data from other devices, it must first learn
what addresses those devices are located at on the network. BACnet client
devices can use dynamic device binding to learn the addresses of other devices
on the network. This is done by sending a Who-Is request on the network. Any
devices whose device instance falls within the range of the Who-Is request will
respond with an I-Am response, informing the client of what network address its
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