LETIMER - Low Energy Timer

Description

Low Energy Timer (LETIMER) Peripheral API.

This module contains functions to control the LETIMER peripheral of Silicon Labs 32-bit MCUs and SoCs. The LETIMER is a down-counter that can keep track of time and output configurable waveforms.

Data Structures

struct LETIMER_Init_TypeDef
LETIMER initialization structure.

Functions

uint32_t LETIMER_CompareGet (LETIMER_TypeDef *letimer, unsigned int comp)
Get the LETIMER compare register value.
void LETIMER_CompareSet (LETIMER_TypeDef *letimer, unsigned int comp, uint32_t value)
Set the LETIMER compare register value.
uint32_t LETIMER_CounterGet (LETIMER_TypeDef *letimer)
Get LETIMER counter value.
void LETIMER_CounterSet (LETIMER_TypeDef *letimer, uint32_t value)
Set LETIMER counter value.
void LETIMER_Enable (LETIMER_TypeDef *letimer, bool enable)
Start/stop LETIMER.
void LETIMER_Init (LETIMER_TypeDef *letimer, const LETIMER_Init_TypeDef *init)
Initialize LETIMER.
void LETIMER_IntClear (LETIMER_TypeDef *letimer, uint32_t flags)
Clear one or more pending LETIMER interrupts.
void LETIMER_IntDisable (LETIMER_TypeDef *letimer, uint32_t flags)
Disable one or more LETIMER interrupts.
void LETIMER_IntEnable (LETIMER_TypeDef *letimer, uint32_t flags)
Enable one or more LETIMER interrupts.
uint32_t LETIMER_IntGet (LETIMER_TypeDef *letimer)
Get pending LETIMER interrupt flags.
uint32_t LETIMER_IntGetEnabled (LETIMER_TypeDef *letimer)
Get enabled and pending LETIMER interrupt flags.
void LETIMER_IntSet (LETIMER_TypeDef *letimer, uint32_t flags)
Set one or more pending LETIMER interrupts from SW.
void LETIMER_Lock (LETIMER_TypeDef *letimer)
Lock LETIMER registers.
void LETIMER_Unlock (LETIMER_TypeDef *letimer)
Unlock LETIMER registers.
uint32_t LETIMER_RepeatGet (LETIMER_TypeDef *letimer, unsigned int rep)
Get the LETIMER repeat register value.
void LETIMER_RepeatSet (LETIMER_TypeDef *letimer, unsigned int rep, uint32_t value)
Set the LETIMER repeat counter register value.
void LETIMER_Reset (LETIMER_TypeDef *letimer)
Reset LETIMER to the same state that it was in after a hardware reset.
void LETIMER_SyncWait (LETIMER_TypeDef *letimer)
Wait for the LETIMER to complete all synchronization of register changes and commands.
void LETIMER_TopSet (LETIMER_TypeDef *letimer, uint32_t value)
Set the LETIMER top value.
uint32_t LETIMER_TopGet (LETIMER_TypeDef *letimer)
Get the current LETIMER top value.

Macros

#define LETIMER_INIT_DEFAULT
Default configuration for LETIMER initialization structure.

Enumerations

enum LETIMER_RepeatMode_TypeDef {
letimerRepeatFree = _LETIMER_CTRL_REPMODE_FREE,
letimerRepeatOneshot = _LETIMER_CTRL_REPMODE_ONESHOT,
letimerRepeatBuffered = _LETIMER_CTRL_REPMODE_BUFFERED,
letimerRepeatDouble = _LETIMER_CTRL_REPMODE_DOUBLE
}
Repeat mode.
enum LETIMER_UFOA_TypeDef {
letimerUFOANone = _LETIMER_CTRL_UFOA0_NONE,
letimerUFOAToggle = _LETIMER_CTRL_UFOA0_TOGGLE,
letimerUFOAPulse = _LETIMER_CTRL_UFOA0_PULSE,
letimerUFOAPwm = _LETIMER_CTRL_UFOA0_PWM
}
Underflow action on output.

Function Documentation

LETIMER_CompareGet()

uint32_t LETIMER_CompareGet ( LETIMER_TypeDef * letimer,
unsigned int comp
)

Get the LETIMER compare register value.

Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] comp A compare register to get, either 0 or 1.
Returns
A compare register value, 0 if invalid register selected.

LETIMER_CompareSet()

void LETIMER_CompareSet ( LETIMER_TypeDef * letimer,
unsigned int comp,
uint32_t value
)

Set the LETIMER 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 comments in the LETIMER_Sync() internal function call.
Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] comp A compare register to set, either 0 or 1.
[in] value An initialization value (<= 0x0000ffff).

LETIMER_CounterGet()

uint32_t LETIMER_CounterGet ( LETIMER_TypeDef * letimer )

Get LETIMER counter value.

Parameters
[in] letimer Pointer to the LETIMER peripheral register block.
Returns
Current LETIMER counter value.

LETIMER_CounterSet()

void LETIMER_CounterSet ( LETIMER_TypeDef * letimer,
uint32_t value
)

Set LETIMER counter value.

Parameters
[in] letimer Pointer to the LETIMER peripheral register block.
[in] value New counter value.

LETIMER_Enable()

void LETIMER_Enable ( LETIMER_TypeDef * letimer,
bool enable
)

Start/stop LETIMER.

Note
The enabling/disabling of the LETIMER modifies the LETIMER CMD 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 comments in the LETIMER_Sync() internal function call.
Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] enable True to enable counting, false to disable.

LETIMER_Init()

void LETIMER_Init ( LETIMER_TypeDef * letimer,
const LETIMER_Init_TypeDef * init
)

Initialize LETIMER.

Note that the compare/repeat values must be set separately with LETIMER_CompareSet() and LETIMER_RepeatSet() . That should probably be done prior using this function if configuring the LETIMER to start when initialization is complete.

Note
The initialization of the LETIMER modifies the LETIMER CTRL/CMD registers which require synchronization into the low-frequency domain. If any of those registers are 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 comments in the LETIMER_Sync() internal function call.
Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] init A pointer to the LETIMER initialization structure.

LETIMER_IntClear()

void LETIMER_IntClear ( LETIMER_TypeDef * letimer,
uint32_t flags
)
inline

Clear one or more pending LETIMER interrupts.

Parameters
[in] letimer Pointer to LETIMER peripheral register block.
[in] flags Pending LETIMER interrupt source to clear. Use a bitwise logic OR combination of valid interrupt flags for the LETIMER module (LETIMER_IF_nnn).

LETIMER_IntDisable()

void LETIMER_IntDisable ( LETIMER_TypeDef * letimer,
uint32_t flags
)
inline

Disable one or more LETIMER interrupts.

Parameters
[in] letimer Pointer to LETIMER peripheral register block.
[in] flags LETIMER interrupt sources to disable. Use a bitwise logic OR combination of valid interrupt flags for the LETIMER module (LETIMER_IF_nnn).

LETIMER_IntEnable()

void LETIMER_IntEnable ( LETIMER_TypeDef * letimer,
uint32_t flags
)
inline

Enable one or more LETIMER interrupts.

Note
Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. To ignore a pending interrupt, consider using LETIMER_IntClear() prior to enabling the interrupt.
Parameters
[in] letimer Pointer to the LETIMER peripheral register block.
[in] flags LETIMER interrupt sources to enable. Use a bitwise logic OR combination of valid interrupt flags for the LETIMER module (LETIMER_IF_nnn).

LETIMER_IntGet()

uint32_t LETIMER_IntGet ( LETIMER_TypeDef * letimer )
inline

Get pending LETIMER interrupt flags.

Note
Event bits are not cleared by the use of this function.
Parameters
[in] letimer Pointer to LETIMER peripheral register block.
Returns
LETIMER interrupt sources pending. A bitwise logic OR combination of valid interrupt flags for the LETIMER module (LETIMER_IF_nnn).

LETIMER_IntGetEnabled()

uint32_t LETIMER_IntGetEnabled ( LETIMER_TypeDef * letimer )
inline

Get enabled and pending LETIMER interrupt flags.

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

Note
Event bits are not cleared by the use of this function.
Parameters
[in] letimer Pointer to LETIMER peripheral register block.
Returns
Pending and enabled LETIMER interrupt sources. Return value is the bitwise AND combination of
  • the OR combination of enabled interrupt sources in LETIMER_IEN_nnn register (LETIMER_IEN_nnn) and
  • the OR combination of valid interrupt flags of the LETIMER module (LETIMER_IF_nnn).

LETIMER_IntSet()

void LETIMER_IntSet ( LETIMER_TypeDef * letimer,
uint32_t flags
)
inline

Set one or more pending LETIMER interrupts from SW.

Parameters
[in] letimer Pointer to LETIMER peripheral register block.
[in] flags LETIMER interrupt sources to set to pending. Use a bitwise logic OR combination of valid interrupt flags for the LETIMER module (LETIMER_IF_nnn).

LETIMER_Lock()

void LETIMER_Lock ( LETIMER_TypeDef * letimer )
inline

Lock LETIMER registers.

Parameters
[in] letimer Pointer to LETIMER peripheral register block.
Note
When LETIMER registers are locked LETIMER_EN, LETIMER_SWRST, LETIMER_CTRL, LETIMER_CMD, LETIMER_CNT, LETIMER_COMPx, LETIMER_TOP, LETIMER_TOPBUFF, LETIMER_REPx, and PRSMODE registers cannot be written to.

LETIMER_Unlock()

void LETIMER_Unlock ( LETIMER_TypeDef * letimer )
inline

Unlock LETIMER registers.

Parameters
[in] letimer Pointer to LETIMER peripheral register block.

LETIMER_RepeatGet()

uint32_t LETIMER_RepeatGet ( LETIMER_TypeDef * letimer,
unsigned int rep
)

Get the LETIMER repeat register value.

Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] rep Repeat register to get, either 0 or 1.
Returns
Repeat register value, 0 if invalid register selected.

LETIMER_RepeatSet()

void LETIMER_RepeatSet ( LETIMER_TypeDef * letimer,
unsigned int rep,
uint32_t value
)

Set the LETIMER repeat counter register value.

Note
The setting of a repeat counter 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 comments in the LETIMER_Sync() internal function call.
Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] rep Repeat counter register to set, either 0 or 1.
[in] value An initialization value (<= 0x0000ffff).

LETIMER_Reset()

void LETIMER_Reset ( LETIMER_TypeDef * letimer )

Reset LETIMER to the same state that it was in after a hardware reset.

Note
The ROUTE register is NOT reset by this function to allow for a centralized setup of this feature.
Parameters
[in] letimer A pointer to the LETIMER peripheral register block.

LETIMER_SyncWait()

void LETIMER_SyncWait ( LETIMER_TypeDef * letimer )

Wait for the LETIMER to complete all synchronization of register changes and commands.

Parameters
[in] letimer A pointer to the LETIMER peripheral register block.

LETIMER_TopSet()

void LETIMER_TopSet ( LETIMER_TypeDef * letimer,
uint32_t value
)

Set the LETIMER top value.

Note
The LETIMER is a down-counter, so when the counter reaches 0 then the top value will be loaded into the counter. This function can be used to set the top value.

If the LETIMER is not already configured to use a top value then this function will enable that functionality for the user.

Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
[in] value The top value. This can be a 16 bit value on series-0 and series-1 devices and a 24 bit value on series-2 devices.

LETIMER_TopGet()

uint32_t LETIMER_TopGet ( LETIMER_TypeDef * letimer )

Get the current LETIMER top value.

Parameters
[in] letimer A pointer to the LETIMER peripheral register block.
Returns
The top value. This will be a 16 bit value on series-0 and series-1 devices and a 24 bit value on series-2 devices.

Macro Definition Documentation

LETIMER_INIT_DEFAULT

#define LETIMER_INIT_DEFAULT
Value:
{ \
true, /* Enable timer when initialization completes. */ \
false, /* Stop counter during debug halt. */ \
false, /* Do not load COMP0 into CNT on underflow. */ \
false, /* Do not load COMP1 into COMP0 when REP0 reaches 0. */ \
0, /* Idle value 0 for output 0. */ \
0, /* Idle value 0 for output 1. */ \
letimerUFOANone, /* No action on underflow on output 0. */ \
letimerUFOANone, /* No action on underflow on output 1. */ \
letimerRepeatFree, /* Count until stopped by SW. */ \
0 /* Use default top Value. */ \
}

Default configuration for LETIMER initialization structure.

Enumeration Type Documentation

LETIMER_RepeatMode_TypeDef

Repeat mode.

Enumerator
letimerRepeatFree

Count until stopped by SW.

letimerRepeatOneshot

Count REP0 times.

letimerRepeatBuffered

Count REP0 times, if REP1 has been written to, it is loaded into REP0 when REP0 is about to be decremented to 0.

letimerRepeatDouble

Run as long as both REP0 and REP1 are not 0.

Both REP0 and REP1 are decremented when counter underflows.

LETIMER_UFOA_TypeDef

Underflow action on output.

Enumerator
letimerUFOANone

No output action.

letimerUFOAToggle

Toggle output when counter underflows.

letimerUFOAPulse

Hold output one LETIMER clock cycle when counter underflows.

letimerUFOAPwm

Set output idle when counter underflows, and active when matching COMP1.