If you can set the PLL fuse and download the hex file, it should be ready to go. The AVR-USB functions have neat way of using the USB bus clock to calibrate the oscillator automatically.
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If you can set the PLL fuse
If you can set the PLL fuse and download the hex file, it should be ready to go. The AVR-USB functions have neat way of using the USB bus clock to calibrate the oscillator automatically.