John N. Power wrote: > I think I made a mistake in the normalization of this formula. It > should be y(n) = (1 - alpha) * x(n) + alpha * y(n-1) Yes this correctly models a simple R/C filter, although it's generally not the way you'd want to implement such a filter on a PIC. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.