ProSoft Technology MVI69-EGD - Manual (Page 32)

MVI69-EGD ♦ CompactLogix or MicroLogix Platform Configuring the MVI69-EGD Module
GE Ethernet Global Data Communication Module
Page 32 of 96 ProSoft Technology, Inc.
November 3, 2008
The purpose of the Configuration Signature (CS) is to guarantee that the
produced exchange will contain data in a format expected by a consumer
module. Therefore it prevents the consumer module to process received data if it
is not compatible because of later modifications.
Whenever a consumer module receives an exchange message, it will look for a
configured consumer exchange that contains the same Exchange ID. If it finds a
matching consumer exchange it will compare the Configuration Signature for
validation.
If the exchange is not validated then the data will not be consumed.
Because this functionality is optional, the modules will exchange data even if the
Configuration Signature validation is disabled. To disable this functionality,
configure all exchanges with both CS Major and CS Minor values equal to zero.
The following rules are used by the consumer module to validate an exchange
based on its Configuration Signature:
Rules for CS Validation
An exchange will be considered valid if at least one of the following conditions is
true:
ƒ Producer CS Major and CS Minor are both equal to 0
ƒ Consumer CS Major and CS Minor are both equal to 0
ƒ Producer CS Major is equal than Consumer CS Major AND Producer CS
Minor is greater or equal than Consumer CS Minor
The following table contains some examples that will help you to understand the
consumer criteria to validate received exchanges based on the Configuration
Signature:
Producer
CS Major Producer
CS Minor Consumer
CS Major Consumer
CS Minor Will Data be
Consumed? Comment
0 0 0 0 Yes Same CS value of 0.0 (Major.Minor) validates the
exchange
0 0 1 2 Yes Producer CS value of 0.0 (Major.Minor) validates
the exchange
1 2 0 0 Yes Consumer CS value of 0.0 (Major.Minor) validates
the exchange
1 2 1 2 Yes Same CS value (1.2) validates the exchange
2 2 1 2 No CS Major mismatch - exchange is not validated
1 2 2 2 No CS Major mismatch - exchange is not validated
1 2 1 1 Yes Same CS Major and Consumer CS Minor is less
than Producer CS Minor - exchange is validated
1 2 1 3 No Same CS Major but Consumer CS Minor is greater
than Producer CS Minor - exchange is not
validated