Echelon Neuron C - Manual (Page 204)

184 Functional Block Declarations
The functional block property list begins with the fb_properties keyword. It then
contains a list of property references, separated by commas, exactly like the
device property list and the network variable property list. Each property
reference must be the name of a previously declared CP family or the name of a
previously declared configuration network variable. The rest of the syntax is
very similar to the network variable property list syntax discussed in the
previous chapter.
Following the property-identifier , there can be an optional initializer , and an
optional range-mod . These optional elements can occur in either order if both are
specified. If present, the instantiation initializer for a CP family member
overrides any initializer provided at the time of declaration of the family; thus,
using this mechanism, some CP family members can be initialized specially, with
the remaining family members having a more generic initial value. If a network
variable is initialized in multiple places (in other words, in its declaration as well
as in its use in a property list), the initializations must match.
Each property instantiation can have a range-modification string following the
property identifier. The range-modification string works identically to the
range-
mod described in Configuration Property Modifiers (cp-modifiers) on page 171. A
range-modification string provided in the instantiation of a CP family member
overrides any range modification string provided in the declaration of the CP
family.
The elements of an fblock array all share the same set of configuration properties
as listed in the associated fb-property-list . Without special keywords, each
element of the fblock array obtains its own set of configuration properties.
Special modifiers can be used to
share individual properties among members of
the same fblock array (through use of the static keyword), or among all the
functional blocks on the device that have the particular property (through use of
the global keyword).
Example:
// CP Family Declarations:
SCPTgain cp_family cpGain;
SCPTlocation cp_family cpLocation;
SCPToffset cp_family cpOffset;
SCPTmaxSndT cp_family cpMaxSendT;
SCPTminSndT cp_family cpMinSendT;
// NV Declarations:
network output SNVT_lev_percent nvoData[4]
nv_properties
{
cpMaxSendT, // throttle interval
cpMinSendT // heartbeat interval
};
// four open loop sensors, implemented as two arrays of
// two sensors, each. This might be beneficial in that
// this software layout might meet the hardware design
// best, for example with regards to shared and individual
// properties.
fblock SFPTopenLoopSensor {
nvoData[0] implements nvoValue;
} MyFb1[2]