using external clock & triggers with a while loop

[jonnie m]

I currently use the wait until next multiple ms to control timing in reading data both from analogue inputs (single reading per channel per loop)and a quadrature encoder. I wish to replace the ms multiple with an external 32hz (digital)signal and to start & stop the acquisition with external triggers. How do I do it?

[SachaE]

Hi,
you haven't said what actual hardware / versions of drivers etc you're using, so I'd suggest looking at the shipping DAQ examples for the environment you're in (I'm assuming Labview since you say "wait until next multiple ms".)
If you go to the help menu item, and into the example finders, you're looking under traditional, or DAQmx, depending on your driver version and what your device supports. Look for things like external (or ext), and pre / post trigger (digital).

Hope that helps
Sacha Emery
National Instruments (UK)

[jonnie m]

sorry - it's labview 6.1 with a 6025E DAQ card.
I've tried looking at the examples, but there's nothing that allows the use of a quadrature encoder at the same time as analogue inputs. The only was I could synchronise the two was using a "wait until next ms multiple". I now want to use an external digital clock pulse to control the timing instead of the "wait until...." in this manner I want to sample all the channels including the position of the quadrature encoder once per clock pulse. I also want the acquisition to be started and stopped by external triggers.
cheers
jonnie