FS-8700-21 LonWorks Manual Page 16 of 62
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Example 2: Setting the Domain and Subnet from the configuration file
FieldServer
System_Station_Address
,Title
[node_id]
,“:D*Domain_ID]:S[Subnet_ID+:*Title continued…+”
The Title field must start with “:D”, followed by the Domain_ID in hexadecimal notation, followed by “:S”, followed by the
Subnet_ID in hexadecimal nota tion and enclosed by “:”. The domain length is automatically determined by the number of
digits in the [Domain_ID] field. Since 2 hexadecimal digits constitute 1 byte, “:D123456:” for example would have a length of
3.
Once the domain table has been set, the “:Dxx:Sxx:” part of the Title field will be removed. Now the Title field will be left with
*Title continued…+ which may be the Node self-documentation string or any title
lon.ini file contents
The file may contain any values or be removed from the FieldServer.
FieldServer configuration file contents ( config.csv )
FieldServer
System_Station_Address
,Title
12
,":D48:S01:TESTING"
Specifying the Domain and Subnet in the configuration file will override the settings from the lon.ini file.
The NVPIEXC command gen erally used for polling has the limitation that data can on ly move in one direction (Server to
Client). The added functionality of a Write-through was added to the network management fetch command (NMFETCHC) to
provide movement of data back to th e polled n ode. Thus, should the data in the Data Array linked to a NMFETCHC Map
Descriptor change by another process, the data will be propagated to the polled node by means of a network variable
update.
Another useful feature of th e NMFETCHC function is that it can perform reads to any other type of Node function (NVUI,
CFG_NVUI, NVUOEXX, NVPIIMC, etc.) This means that even Client Map Descriptors can be read this way.
Network management fetch requests received on polled nodes are handled differently from normal NV Poll requests. The
response to a NV Poll will contain valid data. Data is valid i f the node that is the source of the data is online and if this data is
not too old. The data in the response to a network management fetch will not be checked for validity, however, it will simply
respond with the current data in the variable.