Hello,
I've noticed that you've submitted a couple of other related posts. The PCI-6602 has an on-board 80 MHz timebase. However, in the "Pulse Generation" mode, the smallest timebase/source divisor you are allowed to use is 4. Therefore, the maximum frequency you can generate with the PCI-6602 is 20 MHz. Although you have not mentioned which development environment you are using, there are "pulse train" shipping examples included with no matter what you are using. For NI-DAQ function calls, look in your ...NI-DAQ\Examples folder. For LabVIEW, in addition to the shipping examples under the Help menu, you might look at this example:
High Frequency Pulse Generation with the PCI-6602 Board (20 MHz max)I hope this helps!
Russell
Applications Engineer
National Instruments
http://www.ni.com/support
