Hi Mike,
I have two ideas:
1. There is an example named "Acquire N Scans Digital Trig.vi". You can find it in LabVIEW 7.0 by going to Help>>Find Examples... and doing a search on triggering digital. In general this does what you want to do, but it looks like it expects two triggers of the same edge (rising or falling). You might be able to modify it by going into the AI Start.vi and changing the parameters on the second call to AI Trigger Config.vi. If you make changes to AI Start.vi, be sure to save it with a new name in your own project somewhere. I'm not sure if this will work, since I haven't tried it. You will also need to read the example description - it is very detailed about which trigger type to choose and how to wire your trigger (start
and stop are two different pins).
2. This is a bit more creative, but I have tried it, so I know it works. The idea is to use your trigger pulse (as a gate input) to control a counter pulse train output - the counter clocks out pulses at a known rate as long as its gate is high. You then use that counter pulse train output as an external clock for your data acquisition. You will need to merge parts of two different examples to achieve this. If you have an E-series board, "Finite Pulse Train (DAQ-STC).vi" will help you with the pulse train. This example uses two counters: one to create a single pulse (like your trigger pulse), and one to output the finite pulse train. You'll need to get rid of the single pulse counter part of the code and use your pulse as the gate to the other counter. The second example is "Cont Acq&Graph ExtScanClk.vi". You will pretty much use this code as is, but you'll wire your counter output in as the scan clock. The example description explains the
connections.
I hope this helps.
Best Regards,
Doug
