Counter as divider and acquisitioin trigger

[Walter Tansini]

Hi!

I would like to do the following in LabView (7), using a PXI 6030E in a PXI (1010) chassis. (If neccesary I'll get a PXI6602).

I would like to have a counter counting down from N, and then generating a pulse, or a trigger on an RTSI line, which starts an analog acquisition on the 6030E. The counter meanwhile has to reload to N and start counting down again. To put it another way, I need a configurable frequency divider which triggers an acquisition. The process needs to be done in hardware as much as possible, because I cannot afford to re-initialize the counter programatically each time it gets to zero. I was planning to use the 6030E's own counter/timers, but the chances are we'll get a 6602 because we need more c
ounters.

Here's your chance to earn my eternal gratitude...

Thanks,

Walter Tansini

[Spencer S.]

Walter,

Although it is possible to load an initial count into a counter, it is not possible to have this value reloaded each time terminal count is reached. You could try using the Z-index functionality of an NI-TIO counter (NI 660x), but I have another idea that may provide the behavior you desire, and it can be accomplished with your PXI-6030E. You should configure a counter to perform pulse train generation. The signal you want to count should be specified as the source of the counter. You should then specify "raw" pulse specs for your pulse train. This will allow you to specify how many pulses of your source signal constitute the delay and pulse width of your pulse train. The shipping example Generate Pulse Train (DAQ-STC).vi demonstrates how to prog
ram this task.

Good luck with your application.

Spencer S.

[Walter Tansini]

Thank you Spencer. I hadn't thought of doing it that way. I'll try it asap.