> Plus, the 628 doesn't have an ADC, only a comparator If continuously variable ADC usn't required and/or the application can use a pot divided into discrete segments, then the comparator can be used as a crude ADC by stepping through the internal reference voltage Joe --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .