Jason White wrote: > Hello , recently I have been looking for better pics to expand to. I found > one it looks great but there's one problem: it has no internal oscillator , > I dont know what type of oscillator to get or what mode I would run it under > . Could somone please give me a few pointers in the right direction ? Thanks > > > PIC : PIC18F452 > BTW this pic has a newer equivilent the PIC18F4520 which does have an internal ocillator. > Oscillator I was looking at: 40 Mhz Clock > Oscillator > - Would this go under external clock input mode ECIO ? > Yes if using an oscilator module like that you want external crystal mode (either EC or ECIO depending on whether you want OSC2 as a clock output or an IO pin) Another (likely cheaper) option is to use a 10MHz crystal running in HSPLL mode. I tend to just copy the crystal circuit from one of microchips demo board schematics. Do not try to use a 40MHz crystal. > what would happen if I put a 200MHz oscillator in (pic rated at 40Mhz) Once you go over the rated clock speed nothing is gauranteed. I've heard of someone accidently running one at arround 80MHz with apparent success but I suspect 200 would be too far over the line. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist