1257 User Manual
Advanced SCPI Operations 7-8
EADS North America Defense
Test and Services, Inc.
©
2001
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Selecting the
Trigger Count
The trigger count determines how many elements will be scanned
in the scan list. That is, if the trigger count is 10, then the scan list
will advance 10 times before halting. Any triggers received from
the selected trigger source will be ignored after the trigger count
has been satisfied.
The syntax for the TRIGGER:COUNT command is:
:TRIGger
[:SEQuence]
:COUNt
<trigger
count>
The <trigger count> is a numeric value between 1 and
21747483647 (2
31
-1).
The present trigger count may be queried by using the
TRIGGER:COUNT? query.
Selecting a Trigger
Delay
The 1257 may be programmed to delay before acting on a trigger.
This provides the ability to slow down the scan list operation if so
desired. The TRIGGER:DELAY command is used to program the
trigger delay. The syntax for this command is:
:TRIGger
[:SEQuence]
:DELay
<trigger
delay>
The <trigger delay> is a real number between 0.0 and 10.0. The
trigger delay is programmed in seconds, with a resolution of 1
microsecond. This is the
resolution
and not the
accuracy
. That
means that you will receive 0.00000 (5 decimal places) when you
read it. Any delay over 10 milliseconds rounds the delay to the
nearest 10 milliseconds.
When a non-zero trigger delay is programmed, the 1257 perform
an “idle wait” for the trigger delay period before acting on the
trigger.
The present trigger delay may be queried by using the
TRIGGER:DELAY? command.
