Tuesday, March 22, 2016

Rapid Triggering With Picoscopes

When you're sampling a repetitive waveform with PicoScope, you probably use the Repeat or Auto trigger modes. After each capture, the software on your PC reset the scope hardware to wait for the next trigger event. During this setup process, the scope is not available to capture a new waveform, resulting in a "dead time" of a millisecond or more between captures.

Events that occur during the dead time, such as digital bus activity, could be missed.

To shorten this dead time, most PicoScope oscilloscopes offer a Rapid trigger mode. This uses hardware in the scope to capture multiple waveforms without waiting for the software, and can reduce the dead time to one or two microseconds. (For details, see the PicoScope data sheet for your scope model.) Rapid trigger mode is available only on fast timebases and is limited to the number of waveforms that will fit in the scope's buffer memory. With deep-memory scopes such as the PicoScope 3000 Series with up to 512 MS of buffer memory, or even the PicoScope 6000 Series with buffer sizes up to 2 GS, this is unlikely to be a significant limitation.

To use Rapid trigger mode:

* Select a fast timebase (1 ms/div or faster) using the Collection Time control

* On the Triggering toolbar set the Trigger type to Rapid

* Select the number of buffers you require using the Rapid Captures control

* Press the space bar or click the Start/Stop button to arm the trigger


Read more about PicoScope's advanced digital triggers:


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