Babak,
the only way how you can use virtual channels in CVI is via the Easy I/O for DAQ-functions. see following KB-entry:
http://digital.ni.com/public.nsf/websearch/133A3232F3F31F6286256A5400749D3D?OpenDocument
i recommend you to use DAQmx if it is possible.
Norbert B.
-NI Germany
Norbert
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