ashwani,
Have you tried looking at the shipping examples that come with the NI-435X driver? There is an example that allows you to write Hex numbers to the digital port.
You can look at the shipping examples by going to (in LabVIEW) Help>>Find Examples...>>Hardware Input and Output>>NI-435X>>Digital>>Read Write Digital Port.vi
Hope this helps!
Abhinav T.
Applications Engineering
National Instruments India
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