Hello,
The developers for the Easy I/O functions and NI-DAQ functions recommend strongly not to mix the two sets of calls. You can try to mix them, but the results will be unpredictable since they are designed as separate ways of accomplishing similar things.
If you do mix them, I would just suggest that you don't mix them for the same type of operation. For instance, if you use NI-DAQ function calls to perform your analog inputs, you probably should not use the Easy I/O functions for analog input.
Basically the two are not designed to work together so the interaction will be unpredictable.
Hope this is helpful,
John N
Applications Engineer
National Instruments