I just figured out how to use the oscillator pin of the AtMega328 chip to drive an additional component. I am working on a project that requires a 16Mhz clock to drive other electronics, and figured that the AtMega328 chip there has a 16Mhz crystal connected to it. Sadly the default fuse programming that the Arduino world uses is a ‘low power’ mode where the voltage on the oscillator pin is only about 200mV. If you re-program the fuses, you can put the oscillator into ‘full swing’ mode. Neat!!

The command line I used was:

avrdude -p m328p -c usbtiny -U lfuse:w:0xf7:m -U hfuse:w:0xda:m

Neat!!! Now I can see a beautiful full voltage sinewave on the Oscillator pin.