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Needing to capture a peak value. Not willing to rely on sofware timing for fear of missing the actual peak in between LabVIEW read cycles. So...might anyone know of an NI hardware (module or standalone) which can capture peaks on its own, holding that value until the next LabVIEW read query? That is to say, an amplifier with this built-in (possibly as analog) inside the module? Sure, I can build one from scratch, but it seems a feature many others would want. I rather think that NI might have it as an option in one or another module for CompacDAQ, etc. But I fail to locoate it and NI's website is not much help, directing me off in different directions. And yes, I know I asked a similar question one time before, but got only a software answer. I'm specifically interested only in a hardware recommendation. The software iteration loop is intrinsically too slow.

Am wanting to know if it is possible to acquire peak & valley readings for voltage (amplified signal from accelerometer) over long durations but with non-huge data files. So not a time history file representing waveforms. Rather a collection of max peaks and min valleys (or even just envelope span as an absolute magnitude) at regular intervals. That is to say the greatest one which occured during said interval. Say my vibration table is running a 10-hour dwell at 1250 Hz, what I'm wanting to do is splice into the acclerometer feedback signal (post amplification) and keep a running log of the max peak and min valley (or said span's greatest magnitude) sampled only at much longer intervals (say once a minute). I am needing the readings sampled to be only that, the max peak & min valley (or greatest magnitude) that transpired during that 1-minute interval (even if it happened only once but without couthing how many). What I don't want is the instantaneous value at the time of sampling which would be useless. Hope that's clear. I've had that feature on other instruments (peak/valley sample & hold, reset at intervals) but am unsure how to accomplish it in LabVIEW. Not even sure if it's a feature of the hardware. Can I do it in voltage using a cDAQ and 9205, for instance? If so how? If not, any suggestions?