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Network Variable Bindings
The LonTalk communication protocol allows data to be shared between devices (either as stand-
alone or with a BAS) on a LonTalk network as is referred to as
peer-to-peer communication
. An
example of peer-to-peer communication would be when two or more devices are serving the same
space, share data (such as a temperature reading) without having to pass the data through a BAS.
Network variables are used to share data between devices. The method used to direct data from
one device to another is called
network variable binding
, or just binding. A network variable output
from one device is bound to a network variable input on another device. An output variable from
one device can be bound to input variables on many other devices.
This section provides information about how to use network variable bindings in MP503
applications.
Network Variables
Each network variable is a standard type. This standard type is referred to as a
standard network
variable type
(SNVT, pronounced
snivet
). To bind two variables together, the variables must be the
same type of network variable. For example, an output of type SNVT_temp_p can only be bound
to an input of type SNVT_temp_p. For more information about SNVTs, refer to
www.lonmark.org
.
Binding Network Variables
Important:
Only LonTalk devices can use network variable binding. Devices on other
communication links do not have this capability.
BAS communication typically does not require the use of network variable binding because a
Tracer Summit BCU automatically binds to the proper data in a device. However, communication
speed can be increased between two devices by binding their data rather than having the BAS read
the information from one device, and then broadcasting it to another.
Use the Rover™ service tool to create bindings (refer to the
Rover Operation and Programming
Guide
(EMTX-SVX01).
MP503 Bindings
The principal uses of an MP503 are to gather data (sensor readings) for use by a BAS or peer device
and to allow a BAS or peer device to control MP503 binary outputs. Therefore, the use of bindings
is very important in MP503 applications.
The following examples in this section illustrate some common applications in which bindings are
used with the MP503.
