Echelon IzoT NodeBuilder - Manual (Page 169)

See the Neuron C Programmer’s Guide and Neuron C Reference Guide for more information
about implementing configuration property arrays.
6. In the Restriction Flags box, you can set configuration property flags that network tools must
check in order to handle the configuration property appropriately. See Editing Mandatory
Configuration Properties earlier in this chapter for more information on these flags.
7. To implement the configuration property as a configuration network variable (CPNV), select the
Configuration Network Variable check box. This enables you to read, write, and bind the
configuration property like a network variable. If this check box is cleared, the configuration
property is implemented as a configuration file. This check box is cleared by default.
Note: CPNVs are have the following limitations: (1) they must be based on network variable
types and must meet the target platform’s network variable size limit (228 bytes starting with
version 21 firmware, 31 bytes with earlier versions); and (2) if the CPNV is implemented as an
array that applies to multiple functional blocks or network variables, the CPNV array must always
be shared statically or globally. It is therefore recommended that you only use CPNVs if your
application requires configuration properties that must be bound or if you are adding a
SCPTnwrkCnfg configuration property.
8. Optionally, in the Initializer property, you can set the value for the configuration property that
will be stored in the LNS network database and set the first time the device is reset after the device
application has been downloaded to the device. If this configuration property is a structure, union,
float, or enumeration, click the box to the right to open the Edit Initializer dialog and enter the
value or values. See Setting Initial Values for Network Variables and Configuration Properties
later in this chapter for more information.
9. If the configuration property is member of a functional block array, you can select the Static CP
check box to create a single configuration property that is shared by all the functional blocks in the
array (this is called static configuration property sharing). Modifying the value of the
configuration property on any functional block in the array modifies it for all of them (only one
variable is allocated). If this check box is cleared, a separate configuration property is created for
each functional block in the array. This check box is cleared by default.
10. Click OK. The optional configuration property is added to the Optional CPs folder.
Note: After you create the optional configuration property, you can edit its properties following the
steps described in Editing Mandatory Configuration Properties earlier in this chapter. For example,
you may want to change the configuration property flags, or change how the configuration property is
implemented (configuration network variable [CPNV] or configuration file [file CP]).
Adding Implementation-specific Network Variables
You can add a network variable member to a functional block or device that is not defined by any
functional profile. This is called an implementation-specific network variable.
Implementation-specific network variables should be avoided as part of a device’s interoperable
interface because they are not documented by a functional profile.
WARNING: If you use implementation-specific network variables in your device
interface, your device will not comply with interoperability guidelines version 3.4
(or better) and therefore cannot be certified by L
ON M ARK .
A better alternative for adding members to a functional profile is to create a user-defined functional
profile template (UFPT) that inherits from an existing standard functional profile template (SFPT), and
then add new mandatory or optional member network variables to the UFPT. This method results in a
new functional profile that you can easily reuse in new devices. See the NodeBuilder Resource Editor
User’s Guide for more information on creating new functional profiles.
In order to add an implementation-specific network variable to a functional block, the scope of the
network variable type must be less than or equal to the scope of the functional profile upon which the
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