Echelon ISI - Manual (Page 65)

63 ISI Programmer’s Guide
Function Name Reason to Override
IsiGetAssembly() This function should be overridden for
applications with compound assemblies
involving multiple network variables,
connections involving functional blocks, or
automatic enrollment. The default
implementation returns the assembly
number as the network variable’s global
index, if a compatible network variable
exists for a simple connection using
standard network variable types. The
default implementation always returns
ISI_NO_ASSEMBLY for an automatic
enrollment request. To support joining a
connection with automatic enrollment, this
callback function must be overridden.
When overriding this function, also consider
overriding the IsiGetNextAssembly()
function.
IsiGetConnection() This function must be overridden when
implementing a custom connection table.
When this function is overridden,
IsiSetConnection() and
IsiGetConnectionTableSize() must also be
overridden. The default implementation of
the connection table has eight entries stored
in EEPROM.
The connection table functions are typically
overridden to create a connection table with
a size fitting the application, or with a
persistent data storage model that fits the
application’s needs. See
Customizing the
ISI Connection Table for more information.
IsiGetConnectionTableSize() This function must be overridden when
implementing a custom connection table.
When this function is overridden,
IsiSetConnection() and IsiGetConnection()
must also be overridden. The default
implementation of the connection table has
eight entries stored in EEPROM.
The connection table functions are typically
overridden to create a connection table with
a size fitting the application, or with a
persistent data storage model that fits the
application’s needs. See Customizing the
ISI Connection Table for more information.