Rockwell Automation 1756-XXXX ControlLogix Digital I/O Modules - Manual (Page 237)

Rockwell Automation Publication 1756-UM058G-EN-P - November 2012 237
Appendix
F
Major Revision Upgrades
With the exception of fast digital I/O modules (catalog numbers 1756-IB16IF,
1756-OB16IEF, and 1756-OB16IEFS), ControlLogix 1756 digital I/O modules
are transitioning to use a new, internal backplane Application Specific Integrated
Circuits (ASIC) chip. As a result, the Major Revision number for these modules
has also been upgraded. Digital I/O modules with the new ASIC have
Major Revision 3.
x.
Modules with the new internal backplane ASIC are form-fit, functional
equivalents to the 2.
x modules.
You can use Major Revision 3.
x modules as direct replacements for Major
Revision 2.
x modules in these cases:
• The electronic keying of the module is specified as Compatible or
Disabled Keying.
• The electronic keying of the module is Exact Keying, then additional steps
are required. See
page 238 for details.
The use of the upgraded ASIC also impacts the firmware revisions that can be
flash upgraded to the module. Digital I/O modules at Major Revision 3.
x cannot
be backflashed to any 2.
x firmware revision. Digital I/O modules at firmware
revision 2.
x cannot be flash upgraded to any firmware revision 3.x.
Topic Page
If Using a Compatible or Disabled Keying I/O Configuration 238
If Using an Exact Match Keying Configuration 238
IMPORTANT Do not backflash your module’s firmware from firmware revision 3.x to 2.x.
Attempting to backflash or downgrade a module’s firmware from 3.x to 2.x will
irreversibly damage the module.
You must return modules damaged by an attempt to backflash to firmware 2.x
to Rockwell Automation.