On Sun, 26 Jan 2003, Scott Pierce wrote:

*>I wrote a program for a 16F84A and first tested it out on a 4Mhz chip.  It
*>worked fine but when burning the program on a 20Mhz 16F84A and changing the
*>ceramic resonator, it doesn't function at all.  Just out of curiosity, I
*>turned off the circuit, put a 4Mhz ceramic resonator in place of the 20Mhz
*>one and it worked with the 20Mhz PIC.  Any ideas?  Thanks.

Did you select HS oscillator ? Did you use the resonator with *its*
specified caps ? Is it one of the recommended resonators (not too low Q) ?

Peter

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