Rockwell Automation 1756-HSC ControlLogix High Speed Counter Module - Manual (Page 75)

Rockwell Automation Publication 1756-UM007C-EN-P - November 2011
Configure the 1756-HSC Module 75
Exact Match keying is also necessary to enable Automatic Firmware Update
for the module via the Firmware Supervisor feature from a Logix5000
controller.
Compatible Keying
Compatible Keying indicates that the module determines whether to accept or
reject communication. Different module families, communication adapters,
and module types implement the compatibility check differently based on the
family capabilities and on prior knowledge of compatible products.
EXAMPLE
In the following scenario,
Exact Match keying prevents I/O
communication:
The module configuration is for a 1756-IB16D module with module
revision 3.1. The physical module is a 1756-IB16D module with
module revision 3.2. In this case, communication is prevented because
the Minor Revision of the module does not match precisely
.
IMPORTANT
Changing electronic keying selections online may cause the I/O
Communication connection to the module to be disrupted and may
result in a loss of data.
Module Configuration
Vendor = Allen-Bradley
Product Type = Digital Input
Module
Catalog Number = 1756-IB16D
Major Revision = 3
Minor Revision = 1
Physical Module
Vendor = Allen-Bradley
Product Type = Digital Input
Module
Catalog Number = 1756-IB16D
Major Revision = 3
Minor Revision = 2
Communication is prevented.