EMU - Energy Management Unit#

Energy Management Unit (EMU) Peripheral API.

This module contains functions to control the EMU peripheral of Silicon Labs 32-bit MCUs and SoCs. The EMU handles the different low energy modes in Silicon Labs microcontrollers.

Modules#

EMU_EM01Init_TypeDef

EMU_EM23Init_TypeDef

EMU_EM4Init_TypeDef

EMU_DCDCBoostInit_TypeDef

Enumerations#

enum
emuBODMode_Active
emuBODMode_Inactive
}

BOD threshold setting selector, active or inactive mode.

enum
emuEM4Shutoff = 0
emuEM4Hibernate = 1
}

EM4 modes.

enum
emuPinRetentionDisable = EMU_EM4CTRL_EM4IORETMODE_DISABLE
emuPinRetentionEm4Exit = EMU_EM4CTRL_EM4IORETMODE_EM4EXIT
emuPinRetentionLatch = EMU_EM4CTRL_EM4IORETMODE_SWUNLATCH
}

EM4 Pin Retention Type.

enum
emuPowerConfig_DcdcToDvdd
}

Power configurations.

enum
emuDcdcMode_Bypass = _DCDC_CTRL_MODE_BYPASS
emuDcdcMode_Regulation = _DCDC_CTRL_MODE_DCDCREGULATION
}

DCDC mode.

enum
emuDcdcBoostDriveSpeed_BestEmi = _DCDC_BSTEM01CTRL_DRVSPEED_DEFAULT_SETTING
emuDcdcBoostDriveSpeed_Default = _DCDC_BSTEM01CTRL_DRVSPEED_DEFAULT_SETTING
emuDcdcBoostDriveSpeed_Intermediate = _DCDC_BSTEM01CTRL_DRVSPEED_DEFAULT_SETTING
emuDcdcBoostDriveSpeed_BestEfficiency = _DCDC_BSTEM01CTRL_DRVSPEED_DEFAULT_SETTING
}

DCDC Boost drive speed.

enum
emuDcdcBoostEM01PeakCurrent_Load10mA = _DCDC_BSTEM01CTRL_IPKVAL_Load10mA
emuDcdcBoostEM01PeakCurrent_Load11mA = _DCDC_BSTEM01CTRL_IPKVAL_Load11mA
emuDcdcBoostEM01PeakCurrent_Load13mA = _DCDC_BSTEM01CTRL_IPKVAL_Load13mA
emuDcdcBoostEM01PeakCurrent_Load15mA = _DCDC_BSTEM01CTRL_IPKVAL_Load15mA
emuDcdcBoostEM01PeakCurrent_Load16mA = _DCDC_BSTEM01CTRL_IPKVAL_Load16mA
emuDcdcBoostEM01PeakCurrent_Load18mA = _DCDC_BSTEM01CTRL_IPKVAL_Load18mA
emuDcdcBoostEM01PeakCurrent_Load20mA = _DCDC_BSTEM01CTRL_IPKVAL_Load20mA
emuDcdcBoostEM01PeakCurrent_Load21mA = _DCDC_BSTEM01CTRL_IPKVAL_Load21mA
emuDcdcBoostEM01PeakCurrent_Load23mA = _DCDC_BSTEM01CTRL_IPKVAL_Load23mA
emuDcdcBoostEM01PeakCurrent_Load25mA = _DCDC_BSTEM01CTRL_IPKVAL_Load25mA
}

DCDC Boost EM01 peak current setting.

enum
emuDcdcBoostToffMaxTimeout_Off = _DCDC_BSTCTRL_BSTTOFFMAX_OFF
emuDcdcBoostToffMaxTimeout_0P35us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_0P35us
emuDcdcBoostToffMaxTimeout_0P63us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_0P63us
emuDcdcBoostToffMaxTimeout_0P91us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_0P91us
emuDcdcBoostToffMaxTimeout_1P19us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_1P19us
emuDcdcBoostToffMaxTimeout_1P47us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_1P47us
emuDcdcBoostToffMaxTimeout_1P75us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_1P75us
emuDcdcBoostToffMaxTimeout_2P03us = _DCDC_BSTCTRL_BSTTOFFMAX_TMAX_2P03us
}

DCDC Boost Toff max timeout.

enum
emuDcdcBoostTonMaxTimeout_Off = _DCDC_BSTCTRL_IPKTMAXCTRL_OFF
emuDcdcBoostTonMaxTimeout_0P35us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_0P35us
emuDcdcBoostTonMaxTimeout_0P63us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_0P63us
emuDcdcBoostTonMaxTimeout_0P91us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_0P91us
emuDcdcBoostTonMaxTimeout_1P19us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_1P19us
emuDcdcBoostTonMaxTimeout_1P47us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_1P47us
emuDcdcBoostTonMaxTimeout_1P75us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_1P75us
emuDcdcBoostTonMaxTimeout_2P03us = _DCDC_BSTCTRL_IPKTMAXCTRL_TMAX_2P03us
}

DCDC Boost peak current detection maximum timeout.

enum
emuDcdcBoostEM23PeakCurrent_Load10mA = _DCDC_BSTEM23CTRL_IPKVAL_Load10mA
}

DCDC Boost EM23 peak current setting.

enum
emuVScaleEM01_HighPerformance = _EMU_STATUS_VSCALE_VSCALE2
emuVScaleEM01_LowPower = _EMU_STATUS_VSCALE_VSCALE1
}

Supported EM0/1 Voltage Scaling Levels.

enum
emuVScaleEM23_FastWakeup = _EMU_CTRL_EM23VSCALE_VSCALE2
emuVScaleEM23_LowPower = _EMU_CTRL_EM23VSCALE_VSCALE0
}

Supported EM2/3 Voltage Scaling Levels.

enum
emuTempAvgNum_16 = _EMU_CTRL_TEMPAVGNUM_N16
emuTempAvgNum_64 = _EMU_CTRL_TEMPAVGNUM_N64
}

Number of samples to use for temperature averaging.

Functions#

void
EMU_EM01Init(const EMU_EM01Init_TypeDef *em01Init)

Update the EMU module with Energy Mode 0 and 1 configuration.

void
EMU_EM23Init(const EMU_EM23Init_TypeDef *em23Init)

Update the EMU module with Energy Mode 2 and 3 configuration.

void

Energy mode 2/3 pre-sleep hook function.

void

EFP's Energy mode 2/3 pre-sleep hook function.

void

Energy mode 2/3 post-sleep hook function.

void

EFP's Energy mode 2/3 post-sleep hook function.

void
EMU_EnterEM2(bool restore)

Enter energy mode 2 (EM2).

void
EMU_EnterEM3(bool restore)

Enter energy mode 3 (EM3).

void
EMU_Save(void)

Save the CMU HF clock select state, oscillator enable, and voltage scaling (if available) before EMU_EnterEM2() or EMU_EnterEM3() are called with the restore parameter set to false.

void

Restore CMU HF clock select state, oscillator enable, and voltage scaling (if available) after EMU_EnterEM2() or EMU_EnterEM3() are called with the restore parameter set to false.

void
EMU_EM4Init(const EMU_EM4Init_TypeDef *em4Init)

Update the EMU module with Energy Mode 4 configuration.

void

Energy mode 4 pre-sleep hook function.

void

EFP's Energy mode 4 pre-sleep hook function.

void

Enter energy mode 4 (EM4).

void

Enter energy mode 4 (EM4).

void

Enter energy mode 4 hibernate (EM4H).

void

Enter energy mode 4 shutoff (EM4S).

void
EMU_MemPwrDown(uint32_t blocks)

Power down memory block.

void
EMU_RamPowerDown(uint32_t start, uint32_t end)

Power down RAM memory blocks.

void

Power up all available RAM memory blocks.

void

Update EMU module with CMU oscillator selection/enable status.

void
EMU_EFPEM01VScale(EMU_VScaleEM01_TypeDef voltage)

Energy mode 01 voltage scaling hook function.

void
EMU_VScaleEM01ByClock(uint32_t clockFrequency, bool wait)

Voltage scale in EM0 and 1 by clock frequency.

void
EMU_VScaleEM01(EMU_VScaleEM01_TypeDef voltage, bool wait)

Force voltage scaling in EM0 and 1 to a specific voltage level.

bool
EMU_DCDCBoostInit(const EMU_DCDCBoostInit_TypeDef *dcdcBoostInit)

Configure the DCDC Boost regulator.

void
EMU_EM01BoostPeakCurrentSet(const EMU_DcdcBoostEM01PeakCurrent_TypeDef boostPeakCurrentEM01)

Set EM01 mode Boost Peak Current setting.

void

Enable/disable Boost External Shutdown Mode.

void

Indicate that the DCDC peripheral bus clock enable has changed allowing RAIL to react accordingly.

sl_status_t
EMU_DCDCModeSet(EMU_DcdcMode_TypeDef dcdcMode)

Set DCDC regulator operating mode.

float

Get temperature in degrees Celsius.

void

Enable/disable EFP Direct Mode.

void

Set to enable EFP to drive Decouple voltage.

void
EMU_EFPDriveDvddSet(bool enable)

Set to enable EFP to drive DVDD voltage.

void

Lock DCDC registers in order to protect them against unintended modification.

void

Unlock the DCDC so that writing to locked registers again is possible.

void
EMU_DCDCSync(uint32_t mask)

Wait for the DCDC to complete all synchronization of register changes.

void

Enter energy mode 1 (EM1).

void

Wait for voltage scaling to complete.

Get current voltage scaling level.

void
EMU_IntClear(uint32_t flags)

Clear one or more pending EMU interrupts.

void
EMU_IntDisable(uint32_t flags)

Disable one or more EMU interrupts.

void
EMU_IntEnable(uint32_t flags)

Enable one or more EMU interrupts.

void
EMU_EFPIntDisable(uint32_t flags)

Disable one or more EFP interrupts.

void
EMU_EFPIntEnable(uint32_t flags)

Enable one or more EFP interrupts.

uint32_t

Get pending EMU EFP interrupt flags.

uint32_t

Get enabled and pending EMU EFP interrupt flags.

void
EMU_EFPIntSet(uint32_t flags)

Set one or more pending EMU EFP interrupts.

void
EMU_EFPIntClear(uint32_t flags)

Clear one or more pending EMU EFP interrupts.

uint32_t

Get pending EMU interrupt flags.

uint32_t

Get enabled and pending EMU interrupt flags.

void
EMU_IntSet(uint32_t flags)

Set one or more pending EMU interrupts.

void
EMU_Lock(void)

Lock EMU registers in order to protect them against unintended modification.

void

Unlock the EMU so that writing to locked registers again is possible.

void

When EM4 pin retention is set to emuPinRetentionLatch, then pins are retained through EM4 entry and wakeup.

bool

Temperature measurement ready status.

float

Get averaged temperature in degrees Celsius.

void
EMU_TemperatureAvgRequest(EMU_TempAvgNum_TypeDef numSamples)

Request averaged temperature.

Macros#

#define
EMU_VSCALE_PRESENT

Voltage scaling present.

#define
EMU_VSCALE_EM01_PRESENT

Voltage scaling for EM01 present.

#define
EMU_SERIES2_DCDC_BOOST_PRESENT

DC-DC boost converter present.

#define
EMU_EM01INIT_DEFAULT undefined

Default initialization of EM0 and 1 configuration.

#define
EMU_EM23INIT_DEFAULT undefined

Default initialization of EM2 and 3 configuration.

#define
EMU_EM4INIT_DEFAULT undefined

Default initialization of EM4 configuration (Series 1 without VSCALE).

#define
EMU_DCDCBOOSTINIT_DEFAULT undefined

Default DCDC Boost initialization.

#define
EMU_TEMP_ZERO_C_IN_KELVIN (273.15f)

Zero degrees Celcius in Kelvin.

Enumeration Documentation#

EMU_BODMode_TypeDef#

EMU_BODMode_TypeDef

BOD threshold setting selector, active or inactive mode.

Enumerator
emuBODMode_Active

Configure BOD threshold for active mode.

emuBODMode_Inactive

Configure BOD threshold for inactive mode.


EMU_EM4State_TypeDef#

EMU_EM4State_TypeDef

EM4 modes.

Enumerator
emuEM4Shutoff

EM4 Shutoff.

emuEM4Hibernate

EM4 Hibernate.


EMU_EM4PinRetention_TypeDef#

EMU_EM4PinRetention_TypeDef

EM4 Pin Retention Type.

Enumerator
emuPinRetentionDisable

No Retention: Pads enter reset state when entering EM4.

emuPinRetentionEm4Exit

Retention through EM4: Pads enter reset state when exiting EM4.

emuPinRetentionLatch

Retention through EM4 and wakeup: call EMU_UnlatchPinRetention() to release pins from retention after EM4 wakeup.


EMU_PowerConfig_TypeDef#

EMU_PowerConfig_TypeDef

Power configurations.

DCDC-to-DVDD is currently the only supported mode.

Enumerator
emuPowerConfig_DcdcToDvdd

DCDC is connected to DVDD.


EMU_DcdcMode_TypeDef#

EMU_DcdcMode_TypeDef

DCDC mode.

Enumerator
emuDcdcMode_Bypass

DCDC regulator bypass.

emuDcdcMode_Regulation

DCDC regulator on.


EMU_DcdcBoostDriveSpeed_TypeDef#

EMU_DcdcBoostDriveSpeed_TypeDef

DCDC Boost drive speed.

Enumerator
emuDcdcBoostDriveSpeed_BestEmi

Recommend no options other than DEFAULT be used here, as there is no benefit.

emuDcdcBoostDriveSpeed_Default

Recommend no options other than DEFAULT be used here, as there is no benefit.

emuDcdcBoostDriveSpeed_Intermediate

Recommend no options other than DEFAULT be used here, as there is no benefit.

emuDcdcBoostDriveSpeed_BestEfficiency

Recommend no options other than DEFAULT be used here, as there is no benefit.


EMU_DcdcBoostEM01PeakCurrent_TypeDef#

EMU_DcdcBoostEM01PeakCurrent_TypeDef

DCDC Boost EM01 peak current setting.

Enumerator
emuDcdcBoostEM01PeakCurrent_Load10mA

Load 10mA.

emuDcdcBoostEM01PeakCurrent_Load11mA

Load 11mA.

emuDcdcBoostEM01PeakCurrent_Load13mA

Load 13mA.

emuDcdcBoostEM01PeakCurrent_Load15mA

Load 15mA.

emuDcdcBoostEM01PeakCurrent_Load16mA

Load 16mA.

emuDcdcBoostEM01PeakCurrent_Load18mA

Load 18mA.

emuDcdcBoostEM01PeakCurrent_Load20mA

Load 20mA.

emuDcdcBoostEM01PeakCurrent_Load21mA

Load 21mA.

emuDcdcBoostEM01PeakCurrent_Load23mA

Load 23mA.

emuDcdcBoostEM01PeakCurrent_Load25mA

Load 25mA.


EMU_DcdcBoostToffMaxTimeout_TypeDef#

EMU_DcdcBoostToffMaxTimeout_TypeDef

DCDC Boost Toff max timeout.

Enumerator
emuDcdcBoostToffMaxTimeout_Off

Toff max off.

emuDcdcBoostToffMaxTimeout_0P35us

Toff max is 0.35us.

emuDcdcBoostToffMaxTimeout_0P63us

Toff max is 0.63us.

emuDcdcBoostToffMaxTimeout_0P91us

Toff max is 0.91us.

emuDcdcBoostToffMaxTimeout_1P19us

Toff max is 1.19us.

emuDcdcBoostToffMaxTimeout_1P47us

Toff max is 1.47us.

emuDcdcBoostToffMaxTimeout_1P75us

Toff max is 1.75us.

emuDcdcBoostToffMaxTimeout_2P03us

Toff max is 2.03us.


EMU_DcdcBoostTonMaxTimeout_TypeDef#

EMU_DcdcBoostTonMaxTimeout_TypeDef

DCDC Boost peak current detection maximum timeout.

Enumerator
emuDcdcBoostTonMaxTimeout_Off

Ton max off.

emuDcdcBoostTonMaxTimeout_0P35us

Ton max is 0.35us.

emuDcdcBoostTonMaxTimeout_0P63us

Ton max is 0.63us.

emuDcdcBoostTonMaxTimeout_0P91us

Ton max is 0.91us.

emuDcdcBoostTonMaxTimeout_1P19us

Ton max is 1.19us.

emuDcdcBoostTonMaxTimeout_1P47us

Ton max is 1.47us.

emuDcdcBoostTonMaxTimeout_1P75us

Ton max is 1.75us.

emuDcdcBoostTonMaxTimeout_2P03us

Ton max is 2.03us.


EMU_DcdcBoostEM23PeakCurrent_TypeDef#

EMU_DcdcBoostEM23PeakCurrent_TypeDef

DCDC Boost EM23 peak current setting.

Enumerator
emuDcdcBoostEM23PeakCurrent_Load10mA

Load 10mA.


EMU_VScaleEM01_TypeDef#

EMU_VScaleEM01_TypeDef

Supported EM0/1 Voltage Scaling Levels.

Enumerator
emuVScaleEM01_HighPerformance

High-performance voltage level.

emuVScaleEM01_LowPower

Low-power optimized voltage level.


EMU_VScaleEM23_TypeDef#

EMU_VScaleEM23_TypeDef

Supported EM2/3 Voltage Scaling Levels.

Enumerator
emuVScaleEM23_FastWakeup

Fast-wakeup voltage level.

emuVScaleEM23_LowPower

Low-power optimized voltage level.


EMU_TempAvgNum_TypeDef#

EMU_TempAvgNum_TypeDef

Number of samples to use for temperature averaging.

Enumerator
emuTempAvgNum_16

16 samples used for temperature averaging.

emuTempAvgNum_64

64 samples used for temperature averaging.


Function Documentation#

EMU_EM01Init#

void EMU_EM01Init (const EMU_EM01Init_TypeDef * em01Init)

Update the EMU module with Energy Mode 0 and 1 configuration.

Parameters
TypeDirectionArgument NameDescription
const EMU_EM01Init_TypeDef *[in]em01Init

Energy Mode 0 and 1 configuration structure.


EMU_EM23Init#

void EMU_EM23Init (const EMU_EM23Init_TypeDef * em23Init)

Update the EMU module with Energy Mode 2 and 3 configuration.

Parameters
TypeDirectionArgument NameDescription
const EMU_EM23Init_TypeDef *[in]em23Init

Energy Mode 2 and 3 configuration structure.


EMU_EM23PresleepHook#

void EMU_EM23PresleepHook (void )

Energy mode 2/3 pre-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is called by EMU_EnterEM2() and EMU_EnterEM3() functions just prior to execution of the WFI instruction. The function implementation does not perform anything, but it is SL_WEAK so that it can be re- implemented in application code if actions are needed.


EMU_EFPEM23PresleepHook#

void EMU_EFPEM23PresleepHook (void )

EFP's Energy mode 2/3 pre-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is similar to EMU_EM23PresleepHook() but is reserved for EFP usage.

Note

  • The function is primarily meant to be used in systems with EFP circuitry. (EFP = Energy Friendly Pmic (PMIC = Power Management IC)). In such systems there is a need to drive certain signals to EFP pins to notify about energy mode transitions.


EMU_EM23PostsleepHook#

void EMU_EM23PostsleepHook (void )

Energy mode 2/3 post-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is called by EMU_EnterEM2() and EMU_EnterEM3() functions just after wakeup from the WFI instruction. The function implementation does not perform anything, but it is SL_WEAK so that it can be re- implemented in application code if actions are needed.


EMU_EFPEM23PostsleepHook#

void EMU_EFPEM23PostsleepHook (void )

EFP's Energy mode 2/3 post-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is similar to EMU_EM23PostsleepHook() but is reserved for EFP usage.

Note

  • The function is primarily meant to be used in systems with EFP circuitry. (EFP = Energy Friendly Pmic (PMIC = Power Management IC)). In such systems there is a need to drive certain signals to EFP pins to notify about energy mode transitions.


EMU_EnterEM2#

void EMU_EnterEM2 (bool restore)

Enter energy mode 2 (EM2).

Parameters
TypeDirectionArgument NameDescription
bool[in]restore
  • true - save and restore oscillators, clocks and voltage scaling, see function details.

  • false - do not save and restore oscillators and clocks, see function details.

When entering EM2, high-frequency clocks are disabled, i.e., HFXO, HFRCO and AUXHFRCO (for AUXHFRCO, see exception note below). When re-entering EM0, HFRCO is re-enabled and the core will be clocked by the configured HFRCO band. This ensures a quick wakeup from EM2.

However, prior to entering EM2, the core may have been using another oscillator than HFRCO. The restore parameter gives the user the option to restore all HF oscillators according to state prior to entering EM2, as well as the clock used to clock the core. This restore procedure is handled by SW. However, since handled by SW, it will not be restored before completing the interrupt function(s) waking up the core!

Note

  • If restoring core clock to use the HFXO oscillator, which has been disabled during EM2 mode, this function will stall until the oscillator has stabilized. Stalling time can be reduced by adding interrupt support detecting stable oscillator, and an asynchronous switch to the original oscillator. See CMU documentation. Such a feature is however outside the scope of the implementation in this function.

  • If ERRATA_FIX_EMU_E110_ENABLE is active, the core's SLEEPONEXIT feature can not be used.

  • If HFXO is re-enabled by this function, and NOT used to clock the core, this function will not wait for HFXO to stabilize. This must be considered by the application if trying to use features relying on that oscillator upon return.

  • If a debugger is attached, the AUXHFRCO will not be disabled if enabled upon entering EM2. It will thus remain enabled when returning to EM0 regardless of the restore parameter.

  • If HFXO autostart and select is enabled by using CMU_HFXOAutostartEnable(), the automatic starting and selecting of the core clocks will be done, regardless of the restore parameter, when waking up on the wakeup sources corresponding to the autostart and select setting.

  • If voltage scaling is supported, the restore parameter is true and the EM0 voltage scaling level is set higher than the EM2 level, then the EM0 level is also restored.

  • On Series 2 Config 2 devices (EFRxG22), this function will also relock the DPLL if the DPLL is used and restore is true.

Note that the hardware will automatically update the HFRCO frequency in the case where voltage scaling is used in EM2/EM3 and not in EM0/EM1. When the restore argument to this function is true then software will restore the original HFRCO frequency after EM2/EM3 wake up. If the restore argument is false then the HFRCO frequency is 19 MHz when coming out of EM2/EM3 and all wait states are at a safe value.

  • The restore option should only be used if all clock control is done via the CMU API.


EMU_EnterEM3#

void EMU_EnterEM3 (bool restore)

Enter energy mode 3 (EM3).

Parameters
TypeDirectionArgument NameDescription
bool[in]restore
  • true - save and restore oscillators, clocks and voltage scaling, see function details.

  • false - do not save and restore oscillators and clocks, see function details.

When entering EM3, the high-frequency clocks are disabled by hardware, i.e., HFXO, HFRCO, and AUXHFRCO (for AUXHFRCO, see exception note below). In addition, the low-frequency clocks, i.e., LFXO and LFRCO are disabled by software. When re-entering EM0, HFRCO is re-enabled and the core will be clocked by the configured HFRCO band. This ensures a quick wakeup from EM3.

However, prior to entering EM3, the core may have been using an oscillator other than HFRCO. The restore parameter gives the user the option to restore all HF/LF oscillators according to state prior to entering EM3, as well as the clock used to clock the core. This restore procedure is handled by software. However, since it is handled by software, it will not be restored before completing the interrupt function(s) waking up the core!

Note

  • If restoring core clock to use an oscillator other than HFRCO, this function will stall until the oscillator has stabilized. Stalling time can be reduced by adding interrupt support detecting stable oscillator, and an asynchronous switch to the original oscillator. See CMU documentation. This feature is, however, outside the scope of the implementation in this function.

  • If ERRATA_FIX_EMU_E110_ENABLE is active, the core's SLEEPONEXIT feature can't be used.

  • If HFXO/LFXO/LFRCO are re-enabled by this function, and NOT used to clock the core, this function will not wait for those oscillators to stabilize. This must be considered by the application if trying to use features relying on those oscillators upon return.

  • If a debugger is attached, the AUXHFRCO will not be disabled if enabled upon entering EM3. It will, therefore, remain enabled when returning to EM0 regardless of the restore parameter.

  • If voltage scaling is supported, the restore parameter is true and the EM0 voltage scaling level is set higher than the EM3 level, then the EM0 level is also restored.

  • On Series 2 Config 2 devices (EFRxG22), this function will also relock the DPLL if the DPLL is used and restore is true.

  • The restore option should only be used if all clock control is done via the CMU API.


EMU_Save#

void EMU_Save (void )

Save the CMU HF clock select state, oscillator enable, and voltage scaling (if available) before EMU_EnterEM2() or EMU_EnterEM3() are called with the restore parameter set to false.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Calling this function is equivalent to calling EMU_EnterEM2() or EMU_EnterEM3() with the restore parameter set to true, but it allows the state to be saved without going to sleep. The state can be restored manually by calling EMU_Restore().


EMU_Restore#

void EMU_Restore (void )

Restore CMU HF clock select state, oscillator enable, and voltage scaling (if available) after EMU_EnterEM2() or EMU_EnterEM3() are called with the restore parameter set to false.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Calling this function is equivalent to calling EMU_EnterEM2() or EMU_EnterEM3() with the restore parameter set to true, but it allows the application to evaluate the wakeup reason before restoring state.


EMU_EM4Init#

void EMU_EM4Init (const EMU_EM4Init_TypeDef * em4Init)

Update the EMU module with Energy Mode 4 configuration.

Parameters
TypeDirectionArgument NameDescription
const EMU_EM4Init_TypeDef *[in]em4Init

Energy Mode 4 configuration structure.


EMU_EM4PresleepHook#

void EMU_EM4PresleepHook (void )

Energy mode 4 pre-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is called by EMU_EnterEM4() just prior to the sequence of writes to put the device in EM4. The function implementation does not perform anything, but it is SL_WEAK so that it can be re-implemented in application code if actions are needed.


EMU_EFPEM4PresleepHook#

void EMU_EFPEM4PresleepHook (void )

EFP's Energy mode 4 pre-sleep hook function.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is similar to EMU_EM4PresleepHook() but is reserved for EFP usage.

Note

  • The function is primarily meant to be used in systems with EFP circuitry. (EFP = Energy Friendly Pmic (PMIC = Power Management IC)). In such systems there is a need to drive certain signals to EFP pins to notify about energy mode transitions.


EMU_EnterEM4#

void EMU_EnterEM4 (void )

Enter energy mode 4 (EM4).

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • Only a power on reset or external reset pin can wake the device from EM4.


EMU_EnterEM4Wait#

void EMU_EnterEM4Wait (void )

Enter energy mode 4 (EM4).

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function waits after the EM4 entry request to make sure the CPU is properly shutdown or the EM4 entry failed.

Note

  • Only a power on reset or external reset pin can wake the device from EM4.


EMU_EnterEM4H#

void EMU_EnterEM4H (void )

Enter energy mode 4 hibernate (EM4H).

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • Retention of clocks and GPIO in EM4 can be configured using EMU_EM4Init before calling this function.


EMU_EnterEM4S#

void EMU_EnterEM4S (void )

Enter energy mode 4 shutoff (EM4S).

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • Retention of clocks and GPIO in EM4 can be configured using EMU_EM4Init before calling this function.


EMU_MemPwrDown#

void EMU_MemPwrDown (uint32_t blocks)

Power down memory block.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]blocks

Specifies a logical OR of bits indicating memory blocks to power down. Bit 0 selects block 1, bit 1 selects block 2, and so on. Memory block 0 cannot be disabled. See the reference manual for available memory blocks for a device.

Note

  • Only a POR reset can power up the specified memory block(s) after power down.


EMU_RamPowerDown#

void EMU_RamPowerDown (uint32_t start, uint32_t end)

Power down RAM memory blocks.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]start

The start address of the RAM region to power down. This address is inclusive.

uint32_t[in]end

The end address of the RAM region to power down. This address is exclusive. If this parameter is 0, all RAM blocks contained in the region from start to the upper RAM address will be powered down.

This function will power down all the RAM blocks that are within a given range. The RAM block layout is different between device families, so this function can be used in a generic way to power down a RAM memory region which is known to be unused.

This function will only power down blocks which are completely enclosed by the memory range given by [start, end).

This is an example to power down all RAM blocks except the first one. The first RAM block is special in that it cannot be powered down by the hardware. The size of the first RAM block is device-specific. See the reference manual to find the RAM block sizes.

EMU_RamPowerDown(SRAM_BASE, SRAM_BASE + SRAM_SIZE);

Note

  • Only a reset can power up the specified memory block(s) after power down on a series 0 device. The specified memory block(s) will stay off until a call to EMU_RamPowerUp() is done on series 1/2.


EMU_RamPowerUp#

void EMU_RamPowerUp (void )

Power up all available RAM memory blocks.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function will power up all the RAM blocks on a device, this means that the RAM blocks are retained in EM2/EM3. Note that this functionality is not supported on Series 0 devices. Only a reset will power up the RAM blocks on a series 0 device.


EMU_UpdateOscConfig#

void EMU_UpdateOscConfig (void )

Update EMU module with CMU oscillator selection/enable status.

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_EFPEM01VScale#

void EMU_EFPEM01VScale (EMU_VScaleEM01_TypeDef voltage)

Energy mode 01 voltage scaling hook function.

Parameters
TypeDirectionArgument NameDescription
EMU_VScaleEM01_TypeDef[in]voltage

Voltage scaling level requested.

This function is called by EMU_VScaleEM01 to let EFP know that voltage scaling is requested.


EMU_VScaleEM01ByClock#

void EMU_VScaleEM01ByClock (uint32_t clockFrequency, bool wait)

Voltage scale in EM0 and 1 by clock frequency.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]clockFrequency

Use CMSIS HF clock if 0 or override to custom clock. Providing a custom clock frequency is required if using a non-standard HFXO frequency.

bool[in]wait

Wait for scaling to complete.

Note


EMU_VScaleEM01#

void EMU_VScaleEM01 (EMU_VScaleEM01_TypeDef voltage, bool wait)

Force voltage scaling in EM0 and 1 to a specific voltage level.

Parameters
TypeDirectionArgument NameDescription
EMU_VScaleEM01_TypeDef[in]voltage

Target VSCALE voltage level.

bool[in]wait

Wait for scaling to complete.

Note


EMU_DCDCBoostInit#

bool EMU_DCDCBoostInit (const EMU_DCDCBoostInit_TypeDef * dcdcBoostInit)

Configure the DCDC Boost regulator.

Parameters
TypeDirectionArgument NameDescription
const EMU_DCDCBoostInit_TypeDef *[in]dcdcBoostInit

The DCDC initialization structure.

Returns

  • True if initialization parameters are valid.


EMU_EM01BoostPeakCurrentSet#

void EMU_EM01BoostPeakCurrentSet (const EMU_DcdcBoostEM01PeakCurrent_TypeDef boostPeakCurrentEM01)

Set EM01 mode Boost Peak Current setting.

Parameters
TypeDirectionArgument NameDescription
const EMU_DcdcBoostEM01PeakCurrent_TypeDef[in]boostPeakCurrentEM01

Boost Peak load current coefficient in EM01 mode.


EMU_BoostExternalShutdownEnable#

void EMU_BoostExternalShutdownEnable (bool enable)

Enable/disable Boost External Shutdown Mode.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

The boost DC-DC converter can be activated or deactivated from a dedicated BOOST_EN pin on the device if enable is true.


EMU_DCDCUpdatedHook#

void EMU_DCDCUpdatedHook (void )

Indicate that the DCDC peripheral bus clock enable has changed allowing RAIL to react accordingly.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function is called after DCDC has been enabled or disabled. The function implementation does not perform anything, but it is SL_WEAK so that it can use the RAIL version if needed.


EMU_DCDCModeSet#

sl_status_t EMU_DCDCModeSet (EMU_DcdcMode_TypeDef dcdcMode)

Set DCDC regulator operating mode.

Parameters
TypeDirectionArgument NameDescription
EMU_DcdcMode_TypeDef[in]dcdcMode

DCDC mode.

Returns

  • Returns the status of the DCDC mode set operation.

    *   SL_STATUS_OK - Operation completed successfully.
    *   SL_STATUS_TIMEOUT - Operation EMU DCDC set mode timeout.
    * 

EMU_TemperatureGet#

float EMU_TemperatureGet (void )

Get temperature in degrees Celsius.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Temperature in degrees Celsius


EMU_EFPDirectModeEnable#

void EMU_EFPDirectModeEnable (bool enable)

Enable/disable EFP Direct Mode.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

True to enable direct mode.


EMU_EFPDriveDecoupleSet#

void EMU_EFPDriveDecoupleSet (bool enable)

Set to enable EFP to drive Decouple voltage.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

True to enable EFP to drive Decouple voltage.

Once set, internal LDO will be disabled, and the EMU will control EFP for voltage-scaling. Note that because this bit disables the internal LDO powering the core, it should not be set until after EFP's DECOUPLE output has been configured and enabled.


EMU_EFPDriveDvddSet#

void EMU_EFPDriveDvddSet (bool enable)

Set to enable EFP to drive DVDD voltage.

Parameters
TypeDirectionArgument NameDescription
bool[in]enable

True to enable EFP to drive DVDD voltage.

Set this if EFP's DCDC output is powering DVDD supply. This mode assumes that internal DCDC is not being used.


EMU_DCDCLock#

void EMU_DCDCLock (void )

Lock DCDC registers in order to protect them against unintended modification.

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_DCDCUnlock#

void EMU_DCDCUnlock (void )

Unlock the DCDC so that writing to locked registers again is possible.

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_DCDCSync#

void EMU_DCDCSync (uint32_t mask)

Wait for the DCDC to complete all synchronization of register changes.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]mask

A bitmask corresponding to SYNCBUSY register defined bits indicating registers that must complete any ongoing synchronization.


EMU_EnterEM1#

void EMU_EnterEM1 (void )

Enter energy mode 1 (EM1).

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_VScaleWait#

void EMU_VScaleWait (void )

Wait for voltage scaling to complete.

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_VScaleGet#

EMU_VScaleEM01_TypeDef EMU_VScaleGet (void )

Get current voltage scaling level.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • Current voltage scaling level.


EMU_IntClear#

void EMU_IntClear (uint32_t flags)

Clear one or more pending EMU interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

Pending EMU interrupt sources to clear. Use one or more valid interrupt flags for the EMU module (EMU_IFC_nnn or EMU_IF_nnn).


EMU_IntDisable#

void EMU_IntDisable (uint32_t flags)

Disable one or more EMU interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EMU interrupt sources to disable. Use one or more valid interrupt flags for the EMU module (EMU_IEN_nnn).


EMU_IntEnable#

void EMU_IntEnable (uint32_t flags)

Enable one or more EMU interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EMU interrupt sources to enable. Use one or more valid interrupt flags for the EMU module (EMU_IEN_nnn).

Note

  • Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. To ignore a pending interrupt, consider using EMU_IntClear() prior to enabling the interrupt.


EMU_EFPIntDisable#

void EMU_EFPIntDisable (uint32_t flags)

Disable one or more EFP interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EFP interrupt sources to disable. Use one or more valid interrupt flags for the EFP module (EFPIENnnn).


EMU_EFPIntEnable#

void EMU_EFPIntEnable (uint32_t flags)

Enable one or more EFP interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EFP interrupt sources to enable. Use one or more valid interrupt flags for the EFP module (EFPIENnnn).


EMU_EFPIntGet#

uint32_t EMU_EFPIntGet (void )

Get pending EMU EFP interrupt flags.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • Event bits are not cleared by the use of this function.

Returns

  • EMU EFP interrupt sources pending. .


EMU_EFPIntGetEnabled#

uint32_t EMU_EFPIntGetEnabled (void )

Get enabled and pending EMU EFP interrupt flags.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Useful for handling more interrupt sources in the same interrupt handler.

Note

  • Interrupt flags are not cleared by the use of this function.

Returns

  • Pending and enabled EMU EFP interrupt sources Return value is the bitwise AND of

    • the enabled interrupt sources in EMU_EFPIEN and

    • the pending interrupt flags EMU_EFPIF.


EMU_EFPIntSet#

void EMU_EFPIntSet (uint32_t flags)

Set one or more pending EMU EFP interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EMU EFP interrupt sources to set to pending. Use one or more valid interrupt flags for the EMU EFP module (EMU_EFPIFSnnn).


EMU_EFPIntClear#

void EMU_EFPIntClear (uint32_t flags)

Clear one or more pending EMU EFP interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

Pending EMU EFP interrupt sources to clear. Use one or more valid interrupt flags for the EMU EFP module.


EMU_IntGet#

uint32_t EMU_IntGet (void )

Get pending EMU interrupt flags.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • Event bits are not cleared by the use of this function.

Returns

  • EMU interrupt sources pending. Returns one or more valid interrupt flags for the EMU module (EMU_IF_nnn).


EMU_IntGetEnabled#

uint32_t EMU_IntGetEnabled (void )

Get enabled and pending EMU interrupt flags.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Useful for handling more interrupt sources in the same interrupt handler.

Note

  • Interrupt flags are not cleared by the use of this function.

Returns

  • Pending and enabled EMU interrupt sources Return value is the bitwise AND of

    • the enabled interrupt sources in EMU_IEN and

    • the pending interrupt flags EMU_IF.


EMU_IntSet#

void EMU_IntSet (uint32_t flags)

Set one or more pending EMU interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

EMU interrupt sources to set to pending. Use one or more valid interrupt flags for the EMU module (EMU_IFS_nnn).


EMU_Lock#

void EMU_Lock (void )

Lock EMU registers in order to protect them against unintended modification.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • If locking EMU registers, they must be unlocked prior to using any EMU API functions modifying EMU registers, excluding interrupt control and regulator control if the architecture has a EMU_PWRCTRL register. An exception to this is the energy mode entering API (EMU_EnterEMn()), which can be used when the EMU registers are locked.


EMU_Unlock#

void EMU_Unlock (void )

Unlock the EMU so that writing to locked registers again is possible.

Parameters
TypeDirectionArgument NameDescription
voidN/A

EMU_UnlatchPinRetention#

void EMU_UnlatchPinRetention (void )

When EM4 pin retention is set to emuPinRetentionLatch, then pins are retained through EM4 entry and wakeup.

Parameters
TypeDirectionArgument NameDescription
voidN/A

The pin state is released by calling this function. The feature allows peripherals or GPIO to be re-initialized after EM4 exit (reset), and when initialization is done, this function can release pins and return control to the peripherals or GPIO.


EMU_TemperatureReady#

bool EMU_TemperatureReady (void )

Temperature measurement ready status.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • True if temperature measurement is ready


EMU_TemperatureAvgGet#

float EMU_TemperatureAvgGet (void )

Get averaged temperature in degrees Celsius.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Note

  • An averaged temperature measurement must first be requested by calling EMU_TemperatureAvgRequest() and waiting for the TEMPAVG interrupt flag to go high.

Returns

  • Averaged temperature


EMU_TemperatureAvgRequest#

void EMU_TemperatureAvgRequest (EMU_TempAvgNum_TypeDef numSamples)

Request averaged temperature.

Parameters
TypeDirectionArgument NameDescription
EMU_TempAvgNum_TypeDef[in]numSamples

Number of temperature samples to average

Note

  • EMU must be unlocked by calling EMU_Unlock() before this function can be called.