Gagir,
Developers Exchange is setup with many catagories so that it is easy to find information on your specific issue. Therefore, you will find better DAQ related answers in the Measurement Devices sections of Developers Exchange. To help keep relevent information in the correct area, I have reposted your question for you. Please visit Developers Exchange -> Measurement Devices -> Multifunction I/O for the repost and replies.
Nick Wilson
Application Engineering
National Instruments
www.ni.com/ask