counter is not ready

Hi,

I am trying to use a counter out from NI 6221 and change the output frequency of TTL waveform on the fly. I have used examples from NI and I figured out I need to use property node of " Couter ready for new value". It is working fine when I am changing frequency but at the moment I set frequency= 0 (Counter says zero is not valid so I set the minimum value which is 0.009313226) the counter does not accept any new value. Basically counter would not get ready for any new value and I have to stop the loop and start it over.

I am wondering if any of you has any idea to reslove this issue,

Thanks,

Saridar