Everett Cox wrote: > Greetings, ev here with another dumb question: I have some > pic16c54-rci/p chips. Can I use a 4 Mhz crystal with them? Everett: Yes, but you must remember that those chips aren't tested for XT operation. I wouldn't use them in a commercial product, but they'll probably work ok for prototypes. -Andy Andrew Warren - fastfwd@ix.netcom.com Fast Forward Engineering, Vista, California http://www.geocities.com/SiliconValley/2499