TanHadron:
There are technically libraries out there that allow you to set the PWM frequency. They are, however, typically labeled as audio "tone" libraries. It doesn't matter if the library is designed for audio, it's still just a PWM library. I've written some of these libraries, some of which will output PWM signals at up to the gigahertz range.
This interests me. Particularly the part about the gigahertz range. I haven't heard of this before. Could you point me to somewhere that explains how this is done?
Sorry, must have been drunk, I meant MEGAhertz, not gigahertz.
One of my tone libraries (toneAC) does PWM control of two pins alternating at up to 2.66 MHz with an ATmega running at 16MHz.
Official site
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Support forum
Sorry about the confusion.
Tim