Hi,
First of all, it would be great if you could give us some information about the hardware you are using.
I suspect it's a 6533 also called DIO-32HS
If this is the case the links below will provide you with some information.
To answer your question: The DIO parameter vi is part of the Traditional NI-DAQ driver and can be found under
Measurement I/O -> Traditional NI-DAQ -> Digital I/O -> Advanced Digital I/O
If you can't find the vi there, you have probably not installed the Traditional NI-DAQ driver.
(you can find it here: http://joule.ni.com/nidu/cds/fn/p/sn/n23:3478.36.5303.927/lang/en )
The 6533 can be used with both Traditional NI-DAQ and NI-DAQmx but not with the 2 at the same time.
So using vi's from NI-DAQmx and Traditional DAQ in your VI won't work.
If you are thinking of using NI-DAQmx as driver then you could use the Timing block and set it on Handshaking -> Burst (Export Clock)
Also you can look at example of NI-DAQmx using the example finder and limiting the search for your hardware on the bottom left.
Then under Hardware input and output -> DAQmx -> Digital handshaking you can find examples.
http://digital.ni.com/public.nsf/allkb/862567530005F09C862566F6007E9FE7?OpenDocument
http://digital.ni.com/public.nsf/websearch/AAED1384D13962DE862566B80064275A?OpenDocument
Kind Regards,
Joris Donders
National Instruments
EMEIA GTM Lead for Semiconductor
www.ni.com/semiconductor