EFM32WG Datasheet, PDF (118/834 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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10.5.4 EMU_EM4CONF - Energy mode 4 configuration register
Offset
0x02C
Reset
Access
Bit Position
Name
Bit
31:17
16
15:5
4
3:2
Name
Reset
Access Description
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
LOCKCONF
0
RW
EM4 configuration lock enable
Lock regulator, BOD and oscillator configuration. This is necessary before going to EM4 if the regulator is to be used in EM4, and
must also be done before a potential entry to backup mode.
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
BUBODRSTDIS
0
RW
Disable reset from Backup BOD in EM4
When set, no reset will be asserted due to Brownout when in EM4.
OSC
0x0
RW
Select EM4 duty oscillator
Value
0
1
2
Mode
ULFRCO
LFRCO
LFXO
Description
ULFRCO is available.
LFRCO is available. Can only be set if LFRCO is running before EM4/backup entry.
LFXO is available. Can only be set if LFXO is available before EM4/backup entry.
1
BURTCWU
0
RW
Backup RTC EM4 wakeup enable
Exit EM4 on Backup RTC interrupt.
0
VREGEN
0
RW
EM4 voltage regulator enable
When set, the voltage regulator is enabled in EM4, enabling operation of the Backup RTC and retention registers.
10.5.5 EMU_BUCTRL - Backup Power configuration register
Offset
0x030
Reset
Access
Bit Position
Name
Bit
Name
Reset
Access Description
31:7
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
6:5
PROBE
0x0
RW
Voltage probe select
Configure which voltage to export to ADC.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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