Echelon Neuron C User Manual

Page 192

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172

Network Variable, Configuration Property, and Message Tag Declarations

cp-option-list

:

cp-option-list

,

cp-option

cp-option

cp-option

:

device_specific | manufacturing_only

| object_disabled | offline | reset_required

range-mod

:

range_mod_string (

concatenated-string-constant

)

There must be at least one keyword in the option list. For multiple keywords, the

keywords can occur in any order, but the same keyword must not appear more
than once. Keywords must be separated by commas.
You can specify the following configuration property options:
device_specific

Specifies a configuration property that should always be
read from the device instead of relying upon the value in

the device interface file or a value stored in a network

database. This mechanism is used for configuration
properties that must be managed by the device or by a

passive configuration tool that does not have access to the

network database. An example of such a configuration
property is a setpoint that is updated by a local operator

interface on the device.

Recommendation: Declare a device_specific CP family or

configuration network variable as const. If the CP family

or configuration property network variable is defined
within a functional profile and the declaration does not

match the profile, the compiler issues a warning message.

manufacturing_only Specifies a factory setting that can be read or written

when the device is manufactured, but is not normally (or

ever) modified in the field. In this way a standard

network tool can be used to calibrate the device when a
device is manufactured, while a field installation tool

would observe the flag in the field and prevent updates or

require a password to modify the value.

object_disabled

Specifies that a network tool must disable the functional

block containing the configuration property, take the

device offline, or ensure that the functional block is
already disabled or the device is already offline, before

modifying the configuration property.

offline

Specifies that a network tool must take this device offline,

or ensure the device is already offline, before modifying

the configuration property.

A configuration property can be declared as both offline

and object_disabled. In this case, the offline declaration

takes precedence.

reset_required

Specifies that a network tool must reset the device after

changing the value of the configuration property.

The optional

range-mod

modifier allows you to specify a range-modification string

that modifies the valid range for the configuration property defined by the

resource file. The range-modification string can only be used with fixed-point

and floating-point types, and consists of a pair of either fixed-point or floating-

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