There is also a crystal socket on STK504 where you can place a crystal. This is
to enable high-frequency crystals (>8MHz) to be used. Because of long wires
and large capacitances on the clock nets on STK500, you should put your HF
crystal on STK504 and not in the socket on STK500.
Fuse settings
To use the different clock options, the AVR's programmable fuses must be set
right. Consult the AVR's datasheet and the STK500 programming section on how
to set the appropriate fuses.
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