Hi you have to look in the exemples :
C:\Program Files\National Instruments\LabVIEW 7.0\examples\daq\anlogin.llb\Cont Acq&Graph (buffered).vi
Here on the front panel, you can configure the number of channels you want
depending on the way you want to make your acquisition (internal / external clock, triggered etc ) you may want to chose another vi in the same llb.
Cheers
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