Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module - Manual (Page 98)

Publication 1756-UM528A-EN-P - April 2004
7-12 Using The Sequence of Events Module in FIFO Mode
I.EventNumber
Per point
(1) Running count of the timestamped input transitions; this tag increments by one with
each new event. The event number is the identifier that uniquely indicates which event
the Sequence of Event module is returning to the controller. When you copy this value to
the O.EventAck tag, the Sequence of Events module begins producing the next event in
its buffer, as the next event becomes the current event.
This value is cleared if the module is reset, as described on page 7-20.
I.CSTTimestamp[2] Per point 64-bit CST timestamp in CST format for the current event.
This value is cleared after the data has been acknowledged via the O.EventAck tag. For
more information on clearing timestamp data, see page 7-17.
I.UCTTimestamp[2] Per point 64-bit UCT timestamp in Universal Coordinated Time format for the event. UCT is
expressed as microseconds elapsed since 1 January 1972. Typically, UCT format is only
used in applications that also use the 1756HP-GPS module. For more information on the
1756HP-GPS module, see Appendix B.
This value is cleared after the data has been acknowledged via the O.EventAck tag. For
more information on clearing timestamp data, see page 7-17.
I.EventPoint Per point Input that recorded the event. Values are 0 - 15, where 0 = Input 0, 1 = Input 1, etc.
I.EventData Per point Indicates if input transitioned OFF or ON.
0 = input transitioned OFF
1 = input transitioned ON
I.ReturningUCTTime Modulewide Indicates if timestamps are in UCT format rather than CST. Typically, UCT format is only
used in applications that also use the 1756HP-GPS module. For more information on the
1756HP-GPS module, see Appendix B.
0 = CST format only (UCT timestamp = 0
1 = UCT format available also
For more information on UCT format, see Appendix B.
I.EventsQueuedCount Modulewide Number of events currently stored in the module’s buffer that have not been read.
(1) With the Per point tags, there is one bit per input. For example, bit 0 represents input 0, bit 7 represents input 7 and so on.
Table 7.3 Input Tags in FIFO Mode
Tag name: Set on a Per Point or
Modulewide basis: Description: