----- Original Message ----- From: "Keith L. Kovala" > Ok, I've read AN826 from Microchip, and while informative... I'm still not > sure whether I want a parallel or series resonant crystal, and if parallel > does it really matter for basic circuits what the load cap value is (other > than it be between 12 and 32 pF)?? I suspect series resonant will work, but > can I get some advice from the pros on this one? Well I'd hardly consider myself a pro, but I can tell you what works for me. Just about everything when it comes to making oscillators! If you just want to play around with the chips try a ceramic resonator with built in capacitors. Its accurate enough for 95% of the things you can do with a pic, and extremely easy to connect. It comes with 3 pins... connect the outer two pins to OSC1 and OSC2 and the center one to ground, then set the pic oscillator mode to HS and boot it up. I found some cheap ceramic resonators at allelectronics.com: http://www.allelectronics.com/cgi-bin/category.cgi?category=197&item=CER-20&type=store for $1 each and I believe they have internal capacitors b/c they work fine without any. If you happen to already have a crystal lying there and want to use it instead, put it across OSC1 and OSC2 with a 220 ohm resistor, then tie each crystal pin to ground with a 10-50pf capacitor (or whatever you have laying around). If it doesn't work you won't hurt the pic (just use some common sense...), so just take it apart and try different values. XTAL: GND ----------------------------------- C1 = = C2 | | | | R1 | | | OSC1 OSC2 || || ------------------------------ PIC 100 ohms < R1 < 1k 10 pf < C1,2 < 50 pf > Why can't this just be easy? All I want to do is play with the chips... why > does this have to be so difficult? (That's a rhetorical question and I > don't expect an answer to that. GRiN) It's not that hard, microchip did all the real work for us! The pic is waiting to run.. it just needs a little nudge. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads