Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module - Manual (Page 121)

Publication 1756-UM528A-EN-P - April 2004
Integrating The HiProm GPS Module (1756HP-GPS) into a ControlLogix Sequence of Events Module System B-3
Using a 1756HP-GPS module, you can convert the CST-format
timestamps, received from a ControlLogix Sequence of Events
module, into a Gregorian wall clock time (WCT) that is easily
understood. Generally, the following occurs in this case:
1. The Sequence of Events module sends timestamps to the
controller after an event cascade.
2. The ControlLogix controller sends a message instruction to the
1756HP-GPS module with a CST-format timestamp; you must
use one MSG per timestamp.
3. The 1756HP-GPS module converts the CST-format timestamp to
UCT and Gregorian wall clock format.
4. 1756HP-GPS module send the new value back to the controller,
delivering the value in whatever format the controller requested
via the MSG configuration
Figure B.2
Controller Sequence of
Events module 1756HP-GPS
module
Timestamps sent in CST format to controller
Timestamp sent in CST format via MSG to 1756HP-GPS
Timestamp converted from CST format to Gregorian and UCT format
Converted timestamp sent to controller