FAQs from Rohde & Schwarz

Scope Rider RTH: How to query when a trigger occured?

Description:

I want to query with remote commands when the RTH has been triggered. So I find out that a signal occured.

The following commands are used:
TRIG:MODE SING
RUN;*OPC
Then I repeat "*ESR?" until the answer is "1"

But the RTH does not respond until an acquistion has been finished. If this takes very long, a VISA timeout occurs.
Increasing the value for the VISA timeout is not helpful for the application.

Resolution:

There is a workaround if the option RTH-K15 "History and segmented memory" is available.

Here is the SCPI sequence:

STOP --> stop the acquistion
CHAN1:HIST ON --> activate the history function
TRIG:MODE NORM --> set the trigger mode to "normal"
RUN --> start the acquistions (this happens after a trigger condition has been detected)

Now query in a loop:
ACQ:AVA?

As long no trigger occurs, the RTH answers with "1".
The response changes to "2" when an acquistions has been done. So you know that a signal has been detected.