Pre-trigger waveform capture

[srgray]

Hello all,

I'm trying to perform a waveform capture using my PXI-4072 DMM card. I'm using an external trigger to start the waveform capture. My question: Is there a way to capture data BEFORE the trigger occurs and have it included in the waveform? I've seen this capability on other cards (usually using some sort of circular buffer while waiting for the trigger).

Thanks,
Stephen

[Nick_F1]

Hi Stephen,

There is not functionality in the waveform mode to do a reference trigger.  I is possible to set the DMM to multipoint fetch and keep an array of previous data.  Then wait for a software trigger and acquire the rest of the points I need.  Basically you can do it programatically but not in hardware.