Tags used in fifo mode – Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module User Manual
Page 141

Publication 1756-UM528A-EN-P - April 2004
Using Module Tags D-7
Tags Used in FIFO Mode
Configuration Tags
Table D.5 describes the configuration tags generated in RSLogix 5000
when you use the Sequence of Events module in FIFO Mode.
O.UCTTime[2]
DINT [2]
These tags are used to configure the Sequence of Events module to send timestamps to
the controller in UCT format. In this case, you must copy a pair of timestamp values from
the 1756HP-GPS module (one in UCT format and the other a corresponding CST format
value) to these tags.
When these tags are nonzero numbers, the Sequence of Events module converts
timestamps from CST format to UCT format before sending them to the controller.
Additionally, I.ReturningUCTTime = 1.
Typically, the following events occur:
• A 1756HP-GPS module produces CST/UCT Time pairs that are sent to
the controller.
• The controller copies the pairs to the Sequence of Events module every pulse per
second (PPS). (We recommend you copy the pairs every PPS.)
• The Sequence of Events module uses the streams of pairs to calculate UCT
timestamps for input data including the use of calculating drift between the
clocks.
If these tags = 0, the Sequence of Events module sends timestamps in CST format and
I.ReturningUCTTime = 0.
O.CSTTime[2]
DINT [2]
Table D.4 Output Tags in CST Per Point Mode
Tag name:
Type:
Description:
Table D.5 Configuration Tags in FIFO Mode
Tag name:
Type:
Description:
C.LatchEvents
BOOL
Latches events so that timestamp data from an input transition will not be
overwritten until acknowledged.
0 = CST not latched (default)
1 = CST latched
For more information on Latch CST, see page 5-7.
C.FilterOffOn
SINT
Sets the OFF to ON filter time for all 16 inputs. Times are set in 1ms increments from
0ms to 50ms.
0 = no filtering
For more information on Software Configurable Input Filters, see page 5-10.