RTC

Detailed Description

Real Time Counter (RTC) Peripheral API.

This module contains functions to control the RTC peripheral of Silicon Labs 32-bit MCUs and SoCs. The RTC ensures timekeeping in low energy modes.

Data Structures
struct	RTC_Init_TypeDef

Macros
#define	RTC_INIT_DEFAULT

Functions
uint32_t	RTC_CompareGet (unsigned int comp)
	Get RTC compare register value. More...
void	RTC_CompareSet (unsigned int comp, uint32_t value)
	Set RTC compare register value. More...
__STATIC_INLINE uint32_t	RTC_CounterGet (void)
	Get RTC counter value. More...
void	RTC_CounterReset (void)
	Restart RTC counter from zero.
__STATIC_INLINE void	RTC_CounterSet (uint32_t value)
	Set the RTC counter value. More...
void	RTC_Enable (bool enable)
	Enable/disable RTC. More...
void	RTC_FreezeEnable (bool enable)
	RTC register synchronization freeze control. More...
void	RTC_Init (const RTC_Init_TypeDef *init)
	Initialize RTC. More...
__STATIC_INLINE void	RTC_IntClear (uint32_t flags)
	Clear one or more pending RTC interrupts. More...
__STATIC_INLINE void	RTC_IntDisable (uint32_t flags)
	Disable one or more RTC interrupts. More...
__STATIC_INLINE void	RTC_IntEnable (uint32_t flags)
	Enable one or more RTC interrupts. More...
__STATIC_INLINE uint32_t	RTC_IntGet (void)
	Get pending RTC interrupt flags. More...
__STATIC_INLINE uint32_t	RTC_IntGetEnabled (void)
	Get enabled and pending RTC interrupt flags. Useful for handling more interrupt sources in the same interrupt handler. More...
__STATIC_INLINE void	RTC_IntSet (uint32_t flags)
	Set one or more pending RTC interrupts from SW. More...
void	RTC_Reset (void)
	Restore RTC to reset state.

Macro Definition Documentation

#define RTC_INIT_DEFAULT

Value:

{                                                            \
  true,    /* Start counting when init done */               \
  false,   /* Disable updating during debug halt */          \
  true     /* Restart counting from 0 when reaching COMP0 */ \
}

Suggested default config for RTC init structure.

Definition at line 68 of file em_rtc.h.

Referenced by UDELAY_Calibrate().

Function Documentation

uint32_t RTC_CompareGet

(

unsigned int

comp

)

Get RTC compare register value.

Parameters

[in]

comp

Compare register to get, either 0 or 1

Returns

Compare register value, 0 if invalid register selected.

Definition at line 117 of file em_rtc.c.

References RTC.

void RTC_CompareSet	(	unsigned int	comp,
		uint32_t	value
	)

Set RTC compare register value.

Note

The setting of a compare register requires synchronization into the low frequency domain. If the same register is modified before a previous update has completed, this function will stall until the previous synchronization has completed. This only applies to the Gecko Family, see comment in the regSync() internal function call.

Parameters

[in]	comp	Compare register to set, either 0 or 1
[in]	value	Initialization value (<= 0x00ffffff)

Definition at line 161 of file em_rtc.c.

References _RTC_COMP0_COMP0_MASK, _RTC_COMP0_COMP0_SHIFT, RTC, RTC_SYNCBUSY_COMP0, and RTC_SYNCBUSY_COMP1.

__STATIC_INLINE uint32_t RTC_CounterGet

(

void

)

Get RTC counter value.

Returns

Current RTC counter value.

Definition at line 90 of file em_rtc.h.

References RTC.

__STATIC_INLINE void RTC_CounterSet

(

uint32_t

value

)

Set the RTC counter value.

Parameters

[in]

value

The new RTC counter value.

Definition at line 103 of file em_rtc.h.

References RTC.

void RTC_Enable

(

bool

enable

)

Enable/disable RTC.

Note

The enabling/disabling of the RTC modifies the RTC CTRL register which requires synchronization into the low frequency domain. If this register is modified before a previous update to the same register has completed, this function will stall until the previous synchronization has completed. This only applies to the Gecko Family, see comment in the regSync() internal function call.

Parameters

[in]

enable

true to enable counting, false to disable.

Definition at line 217 of file em_rtc.c.

References _RTC_CTRL_EN_SHIFT, BUS_RegBitWrite(), RTC, and RTC_SYNCBUSY_CTRL.

Referenced by RTC_CounterReset(), RTCDRV_DeInit(), and UDELAY_Calibrate().

void RTC_FreezeEnable

(

bool

enable

)

RTC register synchronization freeze control.

Some RTC registers require synchronization into the low frequency (LF) domain. The freeze feature allows for several such registers to be modified before passing them to the LF domain simultaneously (which takes place when the freeze mode is disabled).

Note

When enabling freeze mode, this function will wait for all current ongoing RTC synchronization to LF domain to complete (Normally synchronization will not be in progress.) However for this reason, when using freeze mode, modifications of registers requiring LF synchronization should be done within one freeze enable/disable block to avoid unecessary stalling. This only applies to the Gecko Family, see the reference manual chapter about Access to Low Energy Peripherals (Asynchronos Registers) for details.

Parameters

[in]

enable

true - enable freeze, modified registers are not propagated to the LF domain false - disables freeze, modified registers are propagated to LF domain

Definition at line 261 of file em_rtc.c.

References RTC, and RTC_FREEZE_REGFREEZE.

Referenced by UDELAY_Calibrate().

void RTC_Init

(

const RTC_Init_TypeDef *

init

)

Initialize RTC.

Note that the compare values must be set separately with RTC_CompareSet(). That should probably be done prior to the use of this function if configuring the RTC to start when initialization is completed.

Note

The initialization of the RTC modifies the RTC CTRL register which requires synchronization into the low frequency domain. If this register is modified before a previous update to the same register has completed, this function will stall until the previous synchronization has completed. This only applies to the Gecko Family, see comment in the regSync() internal function call.

Parameters

[in]

init

Pointer to RTC initialization structure.

Definition at line 305 of file em_rtc.c.

References RTC_Init_TypeDef::comp0Top, RTC_Init_TypeDef::debugRun, RTC_Init_TypeDef::enable, RTC, RTC_CTRL_COMP0TOP, RTC_CTRL_DEBUGRUN, RTC_CTRL_EN, and RTC_SYNCBUSY_CTRL.

Referenced by RTCDRV_Init(), and UDELAY_Calibrate().

__STATIC_INLINE void RTC_IntClear

(

uint32_t

flags

)

Clear one or more pending RTC interrupts.

Parameters

[in]

flags

RTC interrupt sources to clear. Use a set of interrupt flags OR-ed together to clear multiple interrupt sources for the RTC module (RTC_IFS_nnn).

Definition at line 123 of file em_rtc.h.

References RTC.

__STATIC_INLINE void RTC_IntDisable

(

uint32_t

flags

)

Disable one or more RTC interrupts.

Parameters

[in]

flags

RTC interrupt sources to disable. Use a set of interrupt flags OR-ed together to disable multiple interrupt sources for the RTC module (RTC_IFS_nnn).

Definition at line 138 of file em_rtc.h.

References RTC.

__STATIC_INLINE void RTC_IntEnable

(

uint32_t

flags

)

Enable one or more RTC interrupts.

Note

Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. Consider using RTC_IntClear() prior to enabling if such a pending interrupt should be ignored.

Parameters

[in]

flags

RTC interrupt sources to enable. Use a set of interrupt flags OR-ed together to set multiple interrupt sources for the RTC module (RTC_IFS_nnn).

Definition at line 158 of file em_rtc.h.

References RTC.

__STATIC_INLINE uint32_t RTC_IntGet

(

void

)

Get pending RTC interrupt flags.

Note

The event bits are not cleared by the use of this function.

Returns

Pending RTC interrupt sources. Returns a set of interrupt flags OR-ed together for multiple interrupt sources in the RTC module (RTC_IFS_nnn).

Definition at line 175 of file em_rtc.h.

References RTC.

__STATIC_INLINE uint32_t RTC_IntGetEnabled

(

void

)

Get enabled and pending RTC interrupt flags. 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 RTC interrupt sources The return value is the bitwise AND of

• the enabled interrupt sources in RTC_IEN and
• the pending interrupt flags RTC_IF

Definition at line 195 of file em_rtc.h.

References RTC.

__STATIC_INLINE void RTC_IntSet

(

uint32_t

flags

)

Set one or more pending RTC interrupts from SW.

Parameters

[in]

flags

RTC interrupt sources to set to pending. Use a set of interrupt flags OR-ed together to set multiple interrupt sources for the RTC module (RTC_IFS_nnn).

Definition at line 213 of file em_rtc.h.

References RTC.