I understood that to be true (to make matters worse, I'm driving two giant 1/4 scale servos (343 oz/in of torque) which draw 800ma each, so I'm sure that probably has something to do with it.. However, when I drive the servos seperate from the circuit is when I am seeing the problem of them rotating on their own. I have noticed if I use two seperate power supplies, and tie the grounds together everything does appear to work fine. Also, how & what do I couple anything anywhere? I'm only using a single 30k cap between GND and +5V on the power regulator. I've also heard of people doing wierd things with their clocks as well, I'm running a 20 Mhz XTAL with 2 33k caps (1 on each lead) to GND. Any suggestions for making this circuit more well rounded? Thanks! --- Dale Botkin wrote: > Robert, > > You'll probably find the servo is causing enough power supply > disruption > to the PIC to cause it to fail. If you don't have plenty of > decoupling > caps on the PIC and the servo, you'll need them. A better approach > is to > keep the power supplies separate if you can. If you're running on > battery > power this is especially true, and if you're using a DC power supply > that > can't keep up with the servo's current spikes you're bound to have > trouble. > > A servo can draw a surprising amount of current. > > Dale > > > On Sat, 10 Feb 2001, Robert Shady wrote: > > > Okay, I've gotten the code done, but now > > I am seeing something very interesting. > > > > I'm running my code against a scope, and > > everything looks beautiful... Then.. > > > > If I power the circuit & the servo from > > the same +5V power supply, things work > > okay for a minute but then the 16F84 > > "locks" (sorry for the technical term, > > but I'm really not sure what happens, > > it just quits running my code). > > > > If I power the servo seperately from > > the circuit, the servo continuously > > rotates (still watching the scope, the > > signal is perfect). > > > > If I power the servo seperately, but > > connect the grounds of the two power > > supplies together, things work okay > > for a minute and then the 16F84 "locks". > > > > I've tried the servo signal wire directly > > into PORTB/0, through a resistor to PORTB/0, > > through a diode to PORTB/0, through a > > resistor and a diode to PORTB/0, all with > > the same results... > > > > Does anybody have any ideas?? This one is > > really stumping me. > > > > I've checked power power supplies, voltages > > are correct (+4.9V) and the signal looks > > clean. I have tied MCLR & VDD to +5V, and > > VSS to GND. > > > > -- Rob > > > > > > > > __________________________________________________ > > Do You Yahoo!? > > Get personalized email addresses from Yahoo! Mail - only $35 > > a year! http://personal.mail.yahoo.com/ > > > > -- > > http://www.piclist.com hint: To leave the PICList > > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > > > > > --- > The most exciting phrase to hear in science, the one that heralds new > discoveries, is not "Eureka!" (I found it!) but "That's funny ..." > -- Isaac Asimov > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > __________________________________________________ Do You Yahoo!? Get personalized email addresses from Yahoo! Mail - only $35 a year! http://personal.mail.yahoo.com/ -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads