Data Sheet

186
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
z Bit 3 – EN32K: 32kHz Output Enable
0: The 32kHz output is disabled.
1: The 32kHz output is enabled.
z Bit 2 – XTALEN: Crystal Oscillator Enable
This bit controls the connections between the I/O pads and the external clock or crystal oscillator:
0: External clock connected on XIN32. XOUT32 can be used as general-purpose I/O.
1: Crystal connected to XIN32/XOUT32.
z Bit 1 – ENABLE: Oscillator Enable
0: The oscillator is disabled.
1: The oscillator is enabled.
z Bit 0 – Reserved
This bit is unused and reserved for future use. For compatibility with future devices, always write this bit to zero
when this register is written. This bit will always return zero when read.