Appendix A API Command Reference
NetScan User’s Manual A-43
T - Set Trigger Configuration
TYPE
Acquisition
EXECUTION
Deferred
SYNTAX
Tstart,
stop,
re-arm,
sync
Configure an acquisition of scan data with the following parameters:
start is the start event
stop is the stop event
re-arm determines if the unit should continue acquiring after the first
acquisition completes, where 1 is on and 0 is off.
sync determines if acquisition events should be synchronized with the
internal timebases, where 1 is on and 0 is off.
T?
Query the present trigger configuration
DESCRIPTION
The Set Trigger Configuration (T) command is the central command which controls how an acquisition is to be
configured. Upon execution of this command the unit enters the acquiring mode. This will be indicated on the
front panel by the flashing of the TRIGGER light. If a pre-trigger has been configured (via the Y com m and), then
the sampling for pre-trigger data will begin at this time.
Since the Set Trigger Configuration command controls the configuration of an ac qui s ition, all other acquisition
dependent commands should be sent before the Set Trigger Configuration command is s ent to the unit. The
commands which should be sent to the unit prior to the Set Trigger Configuration command will depend on the
desired start and/or stop triggers. For instance, if configuring for Trigger on Comm and, it would not be necessary
to send the Set Trigger Level (L) command.
The following table lists the valid trigger types and their associated required prior issue com mands.
Start/Stop
Trigger
Type
Start/Stop Trigger Definition
Pre-Trigger/
Post Stop
Required Prior Issue
Commands
0
None - Event Not Defined
(N/A)
(N/A)
(N/A)
(N/A)
1
Trigger on Command(See @ command)
yes
I,Y
no
I
4
Trigger on Channel Above Level (L command)
yes
I,Y,L
no
I,L
5
Trigger on Channel Below Level (L command)
yes
I,Y,L
no
I,L
6
Trigger on TTL Signal Rising
yes
I,Y
no
I
7
Trigger on TTL Signal Falling
yes
I,Y
no
I
8
Trigger on Count (Y command)
—
I,Y
9
Trigger on Alarm Turning On (C command)
yes
I,Y,C,A (A is optional)
no
I,C,A (A is optional)
10
Trigger on Alarm Turning Off (C command)
yes
I,Y,C,A (A is optional)
no
I,C,A (A is optional)
11
Trigger on Absolute Time (P command)
yes
I,Y,P
no
I,P
Note: If the start and stop triggers are of different types, a combinati on of t he start and stop prior issue
commands is required.
The Set Trigger Configuration (T) command is used to configure the manner in which scans are t o be ac quired.
It sets the sources to determine when an acquisition is to be initiated and when it is t o be terminated. It also
determines how these acquisition sources are to be (if at all) synchronized with the internal s c an intervals (I)
command. Likewise, it may allow the acquisition to re-enable itself (with t he same configuration) after the initial
acquisition has been terminated.