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Generating 3 control signals

Hi,

I have a PXI6071E multifunction board that I would like to use to generate
3 simple (at least I thought this would be simple...) digital control
signals. The first one is a 1us pulse, coming every 1ms (period=1ms+1us).
The second and third signals are the same as the first, but delayed by 2us,
so that there is a 1us delay between each.

I know how to generate one signal with the delayed pulse VI and a counter.
But the board has only 2 counters... Is there a way to make the two other
signals dependendent on the first one, without the need of a seperate
counter for each of them? I thought of using a counter in a loop and
decoding the counter value to generate my three signals, but the minimal
delay in a Labview l
oop is in the range of 1ms (I would need 1us). Is there
a way to do this? I am just starting with LabView and NI DAQ boards, so
maybe I am missing something fundamental.

Thanks!
Benoit

--
--------------------------------------------------------------
| Benoit Provost
| AMSC, Texas A&M University
| provost@ee.tamu.edu
| (979) 845-5900
| http://amesp02.tamu.edu/~provost
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Effectively you cannot generate three pulse trains from the PXI-6071E board due to only having 2 counters. Moreover, a pulse width of 1us is achievable with a pulse period of 1 ms (i.e., effective frequency = 1000 Hz) using counters, however you could not achieve these pulse train rates using the DIO lines. In short, you are limited to only 2 pulse trains. If you can drive your digital circuitry with the DIO lines (at lower speeds than the counter/timers) then you can modify your program to take advantage of these lines.

National Instruments does have products with up to 8 counter/timers per board. The PCI-6602 has 8 counter timers and an internal max timebase of 80 MHz. Please see www.ni.com/catalog for more information on counter/timer boards.
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