How to use pulse width qualifiers to detect latching trigger

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bloer
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How to use pulse width qualifiers to detect latching trigger

Post by bloer » Mon Feb 04, 2019 7:29 pm

I have a Picoscope 5444B. In my application, the trigger is a digital latch (several seconds long) on EXT. In early testing, it worked fine to use a simple rising edge trigger. However I'm now in an environment where I am getting occasional bursts of noise pickup on that line that are causing spurious triggers. The noise bursts last for a few microseconds. So I would like to trigger on a pulse that rises above threshold and remains above threshold for ~1 ms, but NOT on the falling edge of such a pulse.

I can't quite figure out how to do this with the ps5000a API. Do I need to set both a trigger threshold (SetTriggerChannel*) and pulse width qualifier? Or just the latter?

Thanks!

Martyn
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Re: How to use pulse width qualifiers to detect latching trigger

Post by Martyn » Mon Feb 11, 2019 11:18 am

Advanced trigger setup using the API commands is a bit of a dark art.

The easiest way to go about this is to first try setting up the trigger using the PicoScope 6 software, and if you are able to trigger on the event exactly as you require we can then work out the settings required for the advanced trigger commands.
Martyn
Technical Support Manager

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