EFM32WG Datasheet, PDF (142/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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Bit
Name
Reset
Access Description
Disables the HFXO. HFXOEN has higher priority if written simultaneously. WARNING: Do not disable the HFRXO if this oscillator
is selected as the source for HFCLK.
2
HFXOEN
0
W1
HFXO Enable
Enables the HFXO.
1
HFRCODIS
0
W1
HFRCO Disable
Disables the HFRCO. HFRCOEN has higher priority if written simultaneously. WARNING: Do not disable the HFRCO if this oscillator
is selected as the source for HFCLK.
0
HFRCOEN
0
W1
HFRCO Enable
Enables the HFRCO.
11.5.10 CMU_CMD - Command Register
Offset
0x024
Reset
Access
Bit Position
Name
Bit
31:7
6:5
4
3
2:0
Name
Reset
Access Description
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
USBCCLKSEL
0x0
W1
USB Core Clock Select
Selects the clock for HFCORECLK_USBC. The status register is updated when the clock switch has taken effect.
Value
1
2
3
Mode
HFCLKNODIV
LFXO
LFRCO
Description
Select HFCLKNODIV as HFCORECLK_USBC.
Select LFXO as HFCORECLK_USBC.
Select LFRCO as HFCORECLK_USBC.
CALSTOP
0
W1
Calibration Stop
Stops the calibration counters.
CALSTART
0
W1
Calibration Start
Starts the calibration, effectively loading the CMU_CALCNT into the down-counter and start decrementing.
HFCLKSEL
0x0
W1
HFCLK Select
Selects the clock source for HFCLK. Note that selecting an oscillator that is disabled will cause the system clock to stop. Check the
status register and confirm that oscillator is ready before switching.
Value
1
2
3
4
Mode
HFRCO
HFXO
LFRCO
LFXO
Description
Select HFRCO as HFCLK.
Select HFXO as HFCLK.
Select LFRCO as HFCLK.
Select LFXO as HFCLK.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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