2.2.1 Writing the OSCLOCK Fuse in FUSE.OSCCFG to ‘1’ Prevents Automatic Loading of Calibration Values
Writing the OSCLOCK fuse in FUSE.OSCCFG to ‘1’ prevents
                the automatic loading of calibration values from the signature row. The device will
                run with an uncalibrated OSC20M oscillator.
Work Around
Do not use OSCLOCK for locking the oscillator calibration value. The
                oscillator calibration value can be locked by writing LOCK in CLKCTRL.OSC20MCALIBB
                to ‘1’.
Affected Silicon Revisions
| Rev. A | Rev. B | 
| X | X | 
