Echelon FTXL - Manual (Page 62)

50 Creating a Model File
file. The API uses this table to access the network variables when the application
runs. In addition, the application can query the data in this table at runtime.
Important: This example is not interoperable because it does not use functional
blocks to define the purpose of these network variables. However, this type of
declaration can define a functioning device for an initial test application.
Functional Blocks without Configuration Properties
The following model file describes a similar meter application as in the previous
example, but implements it using functional blocks to provide an interoperable
interface:
• A node object based on the SFPTnodeObject functional profile to manage
the entire device
• An array of three meters, each based on the same user-defined
UFPTenergyMeter profile, implementing three identical meters.
Configuration properties are not used in this example.
// node object:
network input
SNVT_obj_request nviNodeRequest;
network output polled SNVT_obj_status nvoNodeStatus;
fblock SFPTnodeObject {
nviNodeRequest implements nviRequest;
nvoNodeStatus implements nvoStatus;
} NodeObject external_name("NodeObject");
// UFPTenergyMeter
// Implements the meter from the previous example.
network input SNVT_amp nviAmpere[3];
network input SNVT_volt nviVoltage[3];
network input SNVT_angle nviCosPhi[3];
network output SNVT_power nvoWattage[3];
network output polled eeprom SNVT_elapsed_tm nvoUsage[3];
fblock UFPTenergyMeter {
nvoWattage[0] implements nvoWattage;
nviAmpere[0] implements nviAmpere;
nviVoltage[0] implements nviVoltage;
nviCosPhi[0] implements nviCosPhi;
nvoUsage[0] implements nvoUsage;
} Meter[3] external_name("Meter");
Because functional blocks only provide logical grouping of network variables and
configuration properties, and meaning to those groups, but do not themselves
contain executable code, the functional blocks appear only in the self-
documentation data generated by the LonTalk Interface Developer utility, but
not in any generated executable code.