21.8.7. 16MHz Internal Oscillator (OSC16M) Control
Name:
OSC16MCTRL
Offset:
0x14
Reset:
0x82
Property:
PAC Write-Protection
Bit
7
6
5
4
3
2
1
0
ONDEMAND
RUNSTDBY
FSEL[1:0]
ENABLE
Access
R/W
R/W
R/W
R/W
R/W
Reset
1
0
0
0
1
Bit 7 – ONDEMAND: On Demand Control
The On Demand operation mode allows the oscillator to be enabled or disabled depending on peripheral
clock requests.
If the ONDEMAND bit has been previously written to '1', the oscillator will only be running when requested
by a peripheral. If there is no peripheral requesting the oscillator’s clock source, the oscillator will be in a
disabled state.
If On Demand is disabled the oscillator will always be running when enabled.
In standby sleep mode, the On Demand operation is still active.
Value
Description
0
The oscillator is always on, if enabled.
1
The oscillator is enabled when a peripheral is requesting the oscillator to be used as a clock
source. The oscillator is disabled if no peripheral is requesting the clock source.
Bit 6 – RUNSTDBY: Run in Standby
This bit controls how the OSC16M behaves during standby sleep mode.
Value
Description
0
The OSC16M is disabled in standby sleep mode if no peripheral requests the clock.
1
The OSC16M is not stopped in standby sleep mode. If ONDEMAND=1, the OSC16M will be
running when a peripheral is requesting the clock. If ONDEMAND=0, the clock source will
always be running in standby sleep mode.
Bits 3:2 – FSEL[1:0]: Oscillator Frequency Selection
These bits control the oscillator frequency range.
Value
Description
0x00
4MHz
0x01
8MHz
0x10
12MHz
0x11
16MHz
Bit 1 – ENABLE: Oscillator Enable
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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