Campbell Scientific CR9000X Measurement and Control System - Manual (Page 191)

Section 6. Data Table Declarations and Output Processing Instructions
Chart 6.2-3 Triggered Data Example 3
Triggered Data Example 3: Chart 6.2-3 depicts a signal that is being feed to a
DataTable that is triggered when the signal is greater than 4 volts. The
DataTable is set-up to store 10 pre-trigger records and 40 post-trigger records.
Again, only 5 records were available before the first trigger occurred. This
results in 46 records being stored for the first event. The next trigger occurs
immediately after the first event. This results in 0 pre-trigger, the trigger, and 40
post-trigger records being stored for this event (total of 41 records). The next
trigger does not occur until Sample #114, allowing for 10 pre-trigger records,
the trigger, and 40 post trigger records being stored (total of 51 records).
Parameter
Enter DATAEVENT PARAMETERS
PreTrigRecs
Constant
The number of records to store before the Start Trigger.
StartTrig The variable or expression test to Trigger copying the pre trigger records into the data table and
start storing each new record..
Variable, or Value Result
Expression 0 Do not trigger
≠ 0 Trigger
StopTrig
Variable,
Expression or
Constant
The variable, expression or constant to test to stop storing to the data table. The CR9000X does
not start checking for the stop trigger until after the Start Trigger occurs. A non-zero (true)
constant may be used to store a fixed number of records when the start trigger occurs (total
number of records = PreTrigRecs+ 1 record for the trigger +PostTrigRecs.). Zero (false) could
be entered if it was desired to continuously store data once the start trigger occurred.
Value Result
0 Do not trigger
≠ 0 Trigger
PostTrigRecs
Constant
The number of records to store after the Stop Trigger occurs.
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