If the ONDEMAND bit has been previously written to '1', the DFLL will only be running when requested by
a peripheral. If there is no peripheral requesting the DFLL clock source, the DFLL will be in a disabled
state.
If On Demand is disabled, the DFLL will always be running when enabled.
In standby sleep mode, the On Demand operation is still active.
Value
Description
0
The DFLL is always on, if enabled.
1
The DFLL is enabled when a peripheral is requesting the DFLL to be used as a clock source.
The DFLL is disabled if no peripheral is requesting the clock source.
Bit 6 – RUNSTDBY: Run in Standby
This bit controls how the DFLL behaves during standby sleep mode:
Value
Description
0
The DFLL is disabled in standby sleep mode if no peripheral requests the clock.
1
The DFLL is not stopped in standby sleep mode. If ONDEMAND is one, the DFLL will be
running when a peripheral is requesting the clock. If ONDEMAND is zero, the clock source
will always be running in standby sleep mode.
Bit 5 – USBCRM: USB Clock Recovery Mode
Value
Description
0
USB Clock Recovery Mode is disabled.
1
USB Clock Recovery Mode is enabled.
Bit 4 – LLAW: Lose Lock After Wake
Value
Description
0
Locks will not be lost after waking up from sleep modes if the DFLL clock has been stopped.
1
Locks will be lost after waking up from sleep modes if the DFLL clock has been stopped.
Bit 3 – STABLE: Stable DFLL Frequency
Value
Description
0
FINE calibration tracks changes in output frequency.
1
FINE calibration register value will be fixed after a fine lock.
Bit 2 – MODE: Operating Mode Selection
Value
Description
0
The DFLL operates in open-loop operation.
1
The DFLL operates in closed-loop operation.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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