Echelon ISI User Manual

Page 65

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.