Hi, Jinx wrote: >can be determined and worked on outside the ISR. Personally I >prefer to have the ISR over and done with just to keep things tidy Agreed, however sometimes one needs every single cycle. Let's say that the pulses actually are shorther than possible to s/w decode on the fly, then it might do the trick to use the isr flag as a 'bit-buffer' :) /Tony -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics