Echelon LonBridg Server - Manual (Page 30)

24 LonBridge API
LonBridge API
The communications between the LonBridge Server and various LonBridge
applications uses the LonBridge API. This API consists of XML strings
(commands) passed as messages between the LonBridge Server and a LonBridge
application.
Each message is a well-formed XML string with a <lon> element as the top-most
element.
Table 3 lists the commands that form the LonBridge API.
Table 3. LonBridge API Commands
Command Message Type Description
<discover> Output Instructs the LonBridge Server to perform device
discovery
<error> Input Allows the LonBridge application to specify error
conditions
<get> Output Retrieves an object and its attributes with
optional matching criteria
<is> Input Announces the current value of the attributes for
a device
<is_new> Input Announces new devices
<is_pending> Input Announces the value of an object before any
change has occurred
<lon> Input or
Output
Defines the LonBridge XML message
<set> Output Modifies one or more objects
General Message Format
Each XML element that defines a message (that is, all elements other than the
<lon> element) can use either of the following formats for the element name:
• Element name (for example, <get>)
• Object name concatenated with the element name (for example,
<o1.get>)
The object.element message format allows you to send the message to a specific
device. Object names must start with the letter o plus a number. This number is
the ID (id attribute) specified for the device by LonBridge. A <get> message