If you are using LabVIEW, you can use the "Generate Pulse Train (NI-TIO).vi" example. With this example you would toggle the source specification to be default PFI line and specify the raw counts. For example, if you wanted to divide your input frequency by 8, you would set the delay and pulse to 4. You then plug your input freq into the default source PFI line for the counter you're using (PFI39 for counter 0, etc.). The divided signal will be available on the output of your selected counter.
Chapter 10 of the LabVIEW Measurements Manual has a section that discusses the concept of how to divide frequencies using the counters on your 6602 board. Check it out; I am sure you find it worthwhile.
