Greetings ALL: Does anyone out there have practical experience (I've already read all the app-notes, talked to the FAI's, the factory techs, etc. etc ad nauseum.) with getting 32.768 KHz watch crystals to start reliably with the PIC's? I'm working primarily with 508/9's and 54's. In the case of the 509's and '54's, I have a circuit in production that works perfectly, repeatably, and starts every time--HOWEVER when I plug in a 509B the oscillator doesn't. Ditto with the 54's--a stock 54 or 54A seems to work fine, the 54B's refuse to oscillate in the same circuit. I am using standard C type crystals from Digikey SE3202 (Epson C-002RX 32Khz 20PPM, 12.5 pF 30KOhms typ. series resistance) with 12 pF load caps in the standard two caps to ground configuration straight out of the data books and tech notes. QUESTION: has anyone else encountered this behavior? What did you do to fix it? Thanks, Kelly ******************************************************************************** **** All legitimate attachments to this email will be clearly identified in the text. William K. Borsum, P.E. OEM Dataloggers and Instrumentation Systems < & <