Echelon FTXL - Manual (Page 213)

FTXL User’s Guide 201
• ProcessOnlineEvent(): Calls the ProcessNviVoltUpdate() function when
the device goes online.
These functions are defined in the main.c file.
Callback Handler Function
To signal to the main application the occurrence of certain types of events, the
FTXL LonTalk API calls specific callback handler functions. For the simple
voltage actuator example application, only one of the API’s callback handler
functions has been implemented to provide application-specific behavior.
The FtxlHandlers.c file contains the modified LonEventReady() function, which is
called when the FTXL LonTalk protocol stack receives a network event. This
function simply calls the myEventReady() function in the main.c file that
provides the application-specific behavior. This functional separation approach
keeps changes to the LonTalk Interface Developer utility-generated files to a
minimum. For a production-level application, you can place application-specific
code wherever your application design requires it.
The myEventReady() function calls the FTXL OSAL OsalSetEvent() function to
signal the application task so that it can process the network event.
The myEventReady() function is shown below.
/* This function is called by the FTXL LonEventReady
* callback, signaling that an event is ready to be
* processed.
*/
void myEventReady(void) {
/* Signal application task so that it can process the
* event. */
OsalSetEvent(eventReadyHandle);
}
Model File
The model file, Simple Example.nc, defines the L ON W ORKS interface for the
example FTXL device.
The model file defines one functional block, VoltActuator. The VoltActuator
functional block includes two network variables, nviVolt and nvoVoltFb. The
functionality for these network variables is implemented in the
myNvUpdateOccurred() function described in Event Handler Function on page
199.
The model file is shown below.
#pragma enable_sd_nv_names
network input SNVT_volt nviVolt;
network output SNVT_volt bind_info(unackd) nvoVoltFb;
fblock SFPTclosedLoopActuator {
nviVolt implements nviValue;
nvoVoltFb implements nvoValueFb;
} VoltActuator
external_name("VoltActuator");