I have a rather esoteric question about using an external xtal and I believe I already know the answer but will throw it out to the experts.
I have an evil mad scientist ATMega328P bare development board that I have installed a 16mHz xtal but I want to run the board at 3.3V.
What I have done is set the fuse to use the internal 8mHz xtal but still have the external xtal in place and am having timing issues.
So my question is even though I have the external xtal installed and have programmed the chip to use the internal xtal, is the external xtal interfering in some way with the operation of the chip?
Thanks