If you are regenerating the same buffer, then you want to make sure the buffer has a whole number of periods. If you have 2.5 periods in your buffer and are regenerating this same buffer, you would get the middle of the third period and then start over at the beginning of your 1st period, giving you a discontinuity. If you are not regenerating the same buffer, then as long as you are picking up where you left off as far as you data goes, you should see the discontinuity. For our previous example, if your next buffer's first point starts at the 2nd half of the 3rd period, you shouldn't see a break in the waveform. Below is a link to a knowledge base that discusses how to calculate the resulting output frequency. I hope this information helps. Respond if this did not answer your question or if you have additional questions.
<a href="http://digital.ni.com/public.nsf/websearch/AD1739FDEDBE080886256DF9007B929A?OpenDocument";>Calculate Frequency</a>
