WDOG - Watchdog Timer#

Watchdog timer peripheral API.

The Watchdog API functions provide full support for the WDOG peripheral. The WDOG resets the system in case of a fault condition.

Example#

The following example demonstrates how to configure and use the Watchdog Timer. This example shows how to initialize the watchdog with a custom configuration, enable interrupts, feed the watchdog, and properly clean up when done.

// WDOG warning interrupt handler
void WDOG0_IRQHandler(void)
{
  // Get pending interrupts
  uint32_t flags = sl_hal_wdog_get_pending_interrupts(WDOG0);

  // Check for warning interrupt
  if (flags & WDOG_IF_WARN) {
    // Clear the warning interrupt flag
    sl_hal_wdog_clear_interrupts(WDOG0, WDOG_IF_WARN);

    // Feed the watchdog before timeout occurs
    sl_hal_wdog_feed(WDOG0);

    // Application can perform other actions here
    // ...
  }
}

void wdog_example(void)
{
  // Initialize WDOG with default configuration
  sl_hal_wdog_init_t init = SL_HAL_WDOG_INIT_DEFAULT;

  // Customize configuration
  init.period_select = SL_WDOG_PERIOD_64k;        // Set timeout period
  init.warning_time_select = SL_WDOG_WARNING_TIME75; // Get warning at 75% of timeout

  // Initialize WDOG with our configuration
  sl_hal_wdog_init(WDOG0, &init);

  // Enable warning interrupt
  sl_hal_wdog_clear_interrupts(WDOG0, WDOG_IF_WARN);
  sl_hal_wdog_enable_interrupts(WDOG0, WDOG_IF_WARN);

  // Enable NVIC interrupt for WDOG
  sl_interrupt_manager_clear_irq_pending(WDOG0_IRQn);
  sl_interrupt_manager_enable_irq(WDOG0_IRQn);

  // Enable WDOG - this starts the watchdog timer
  sl_hal_wdog_enable(WDOG0);

  // Verify WDOG is enabled (optional)
  if (sl_hal_wdog_is_enabled(WDOG0)) {
    // WDOG is now running

    // Feed the watchdog initially
    sl_hal_wdog_feed(WDOG0);

    // Wait for feed operation to complete
    sl_hal_wdog_wait_sync(WDOG0);

    // Main application loop would continue here
    // The watchdog will now trigger a warning interrupt at 75% of timeout
    // which will feed the watchdog in the interrupt handler
    // ...
  }

  // When no longer needed, disable the watchdog (if not locked)
  if (!sl_hal_wdog_is_locked(WDOG0)) {
    sl_hal_wdog_disable(WDOG0);
    sl_hal_wdog_wait_ready(WDOG0);

    // Disable NVIC interrupt for WDOG
    sl_interrupt_manager_disable_irq(WDOG0_IRQn);
  }
}

Modules#

sl_hal_wdog_init_t

Enumerations#

enum

sl_hal_wdog_period_select_t {

SL_WDOG_PERIOD_9 = _WDOG_CFG_PERSEL_SEL0

SL_WDOG_PERIOD_17 = _WDOG_CFG_PERSEL_SEL1

SL_WDOG_PERIOD_33 = _WDOG_CFG_PERSEL_SEL2

SL_WDOG_PERIOD_65 = _WDOG_CFG_PERSEL_SEL3

SL_WDOG_PERIOD_129 = _WDOG_CFG_PERSEL_SEL4

SL_WDOG_PERIOD_257 = _WDOG_CFG_PERSEL_SEL5

SL_WDOG_PERIOD_513 = _WDOG_CFG_PERSEL_SEL6

SL_WDOG_PERIOD_1k = _WDOG_CFG_PERSEL_SEL7

SL_WDOG_PERIOD_2k = _WDOG_CFG_PERSEL_SEL8

SL_WDOG_PERIOD_4k = _WDOG_CFG_PERSEL_SEL9

SL_WDOG_PERIOD_8k = _WDOG_CFG_PERSEL_SEL10

SL_WDOG_PERIOD_16k = _WDOG_CFG_PERSEL_SEL11

SL_WDOG_PERIOD_32k = _WDOG_CFG_PERSEL_SEL12

SL_WDOG_PERIOD_64k = _WDOG_CFG_PERSEL_SEL13

SL_WDOG_PERIOD_128k = _WDOG_CFG_PERSEL_SEL14

SL_WDOG_PERIOD_256k = _WDOG_CFG_PERSEL_SEL15

}

Watchdog timeout period selection.

enum

sl_hal_wdog_warning_timeout_select_t {

SL_WDOG_WARNING_DISABLE = _WDOG_CFG_WARNSEL_DIS

SL_WDOG_WARNING_TIME25 = _WDOG_CFG_WARNSEL_SEL1

SL_WDOG_WARNING_TIME50 = _WDOG_CFG_WARNSEL_SEL2

SL_WDOG_WARNING_TIME75 = _WDOG_CFG_WARNSEL_SEL3

}

Select Watchdog warning timeout period as percentage of timeout.

enum

sl_hal_wdog_illegal_window_select_t {

SL_WDOG_ILLEGAL_WINDOW_DISABLE = _WDOG_CFG_WINSEL_DIS

SL_WDOG_ILLEGAL_WINDOW_TIME12_5 = _WDOG_CFG_WINSEL_SEL1

SL_WDOG_ILLEGAL_WINDOW_TIME25_0 = _WDOG_CFG_WINSEL_SEL2

SL_WDOG_ILLEGAL_WINDOW_TIME37_5 = _WDOG_CFG_WINSEL_SEL3

SL_WDOG_ILLEGAL_WINDOW_TIME50_0 = _WDOG_CFG_WINSEL_SEL4

SL_WDOG_ILLEGAL_WINDOW_TIME62_5 = _WDOG_CFG_WINSEL_SEL5

SL_WDOG_ILLEGAL_WINDOW_TIME75_0 = _WDOG_CFG_WINSEL_SEL6

SL_WDOG_ILLEGAL_WINDOW_TIME87_5 = _WDOG_CFG_WINSEL_SEL7

}

Select Watchdog illegal window limit.

Functions#

void

sl_hal_wdog_enable(WDOG_TypeDef *wdog)

Enable the watchdog peripheral.

void

sl_hal_wdog_disable(WDOG_TypeDef *wdog)

Disable the watchdog peripheral.

void

sl_hal_wdog_feed(WDOG_TypeDef *wdog)

Feed the watchdog peripheral.

void

sl_hal_wdog_init(WDOG_TypeDef *wdog, const sl_hal_wdog_init_t *init)

Initialize watchdog (assuming the watchdog configuration has not been locked).

void

sl_hal_wdog_lock(WDOG_TypeDef *wdog)

Lock the watchdog configuration.

void

sl_hal_wdog_wait_sync(WDOG_TypeDef *wdog)

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

void

sl_hal_wdog_wait_ready(WDOG_TypeDef *wdog)

Wait for the watchdog to be completely disabled after calling sl_hal_wdog_disable().

void

sl_hal_wdog_unlock(WDOG_TypeDef *wdog)

Unlock the watchdog configuration.

void

sl_hal_wdog_clear_interrupts(WDOG_TypeDef *wdog, uint32_t flags)

Clear one or more pending watchdog interrupts.

void

sl_hal_wdog_disable_interrupts(WDOG_TypeDef *wdog, uint32_t flags)

Disable one or more watchdog interrupts.

void

sl_hal_wdog_enable_interrupts(WDOG_TypeDef *wdog, uint32_t flags)

Enable one or more watchdog interrupts.

uint32_t

sl_hal_wdog_get_pending_interrupts(WDOG_TypeDef *wdog)

Get pending watchdog interrupt flags.

uint32_t

sl_hal_wdog_get_enabled_pending_interrupts(WDOG_TypeDef *wdog)

Get enabled and pending watchdog interrupt flags.

void

sl_hal_wdog_set_interrupts(WDOG_TypeDef *wdog, uint32_t flags)

Set one or more pending watchdog interrupts from SW.

bool

sl_hal_wdog_is_enabled(WDOG_TypeDef *wdog)

Get enabled status of the watchdog.

bool

sl_hal_wdog_is_locked(WDOG_TypeDef *wdog)

Get locked status of the watchdog.

Macros#

#define

SL_HAL_WDOG_REF_VALID (ref)

Check if WDOG instance is valid.

#define

SL_HAL_WDOG_INIT_DEFAULT undefined

Suggested default configuration for WDOG initialization structure.

Enumeration Documentation#

sl_hal_wdog_period_select_t#

sl_hal_wdog_period_select_t

Watchdog timeout period selection.

Enumerator
SL_WDOG_PERIOD_9	9 clock periods.
SL_WDOG_PERIOD_17	17 clock periods.
SL_WDOG_PERIOD_33	33 clock periods.
SL_WDOG_PERIOD_65	65 clock periods.
SL_WDOG_PERIOD_129	129 clock periods.
SL_WDOG_PERIOD_257	257 clock periods.
SL_WDOG_PERIOD_513	513 clock periods.
SL_WDOG_PERIOD_1k	1025 clock periods.
SL_WDOG_PERIOD_2k	2049 clock periods.
SL_WDOG_PERIOD_4k	4097 clock periods.
SL_WDOG_PERIOD_8k	8193 clock periods.
SL_WDOG_PERIOD_16k	16385 clock periods.
SL_WDOG_PERIOD_32k	32769 clock periods.
SL_WDOG_PERIOD_64k	65537 clock periods.
SL_WDOG_PERIOD_128k	131073 clock periods.
SL_WDOG_PERIOD_256k	262145 clock periods.

sl_hal_wdog_warning_timeout_select_t#

sl_hal_wdog_warning_timeout_select_t

Select Watchdog warning timeout period as percentage of timeout.

Enumerator
SL_WDOG_WARNING_DISABLE	Watchdog warning period is disabled.
SL_WDOG_WARNING_TIME25	Watchdog warning period is 25% of the timeout.
SL_WDOG_WARNING_TIME50	Watchdog warning period is 50% of the timeout.
SL_WDOG_WARNING_TIME75	Watchdog warning period is 75% of the timeout.

sl_hal_wdog_illegal_window_select_t#

sl_hal_wdog_illegal_window_select_t

Select Watchdog illegal window limit.

Enumerator
SL_WDOG_ILLEGAL_WINDOW_DISABLE	Watchdog illegal window disabled.
SL_WDOG_ILLEGAL_WINDOW_TIME12_5	Window timeout is 12.5% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME25_0	Window timeout is 25% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME37_5	Window timeout is 37.5% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME50_0	Window timeout is 50% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME62_5	Window timeout is 62.5% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME75_0	Window timeout is 75% of the timeout.
SL_WDOG_ILLEGAL_WINDOW_TIME87_5	Window timeout is 87.5% of the timeout.

Function Documentation#

sl_hal_wdog_enable#

void sl_hal_wdog_enable (WDOG_TypeDef * wdog)

Enable the watchdog peripheral.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Note

This function modifies the WDOG 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.

sl_hal_wdog_disable#

void sl_hal_wdog_disable (WDOG_TypeDef * wdog)

Disable the watchdog peripheral.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Note

This function modifies the WDOG 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.

sl_hal_wdog_feed#

void sl_hal_wdog_feed (WDOG_TypeDef * wdog)

Feed the watchdog peripheral.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

When WDOG is activated, it must be fed (i.e., clearing the counter) before it reaches the defined timeout period. Otherwise, WDOG will generate a reset.

Note

Note that WDOG is an asynchronous peripheral and when calling the sl_hal_wdog_feed() function the hardware starts the process of clearing the counter. This process takes some time before it completes depending on the selected oscillator (up to 4 peripheral clock cycles). When using the ULFRCO for instance as the oscillator the watchdog runs on a 1 kHz clock and a watchdog clear operation might take up to 4 ms.

If the device supports EM2 or EM3 and it enters EM2 or EM3 while a command is in progress then that command will be aborted. An application can use sl_hal_wdog_sync_wait() to wait for a command to complete.

sl_hal_wdog_init#

void sl_hal_wdog_init (WDOG_TypeDef * wdog, const sl_hal_wdog_init_t * init)

Initialize watchdog (assuming the watchdog configuration has not been locked).

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.
const sl_hal_wdog_init_t *	[in]	init	The structure holding the WDOG configuration. A default setting #WDOG_INIT_DEFAULT is available for initialization.

Note

This function modifies the WDOG 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.

sl_hal_wdog_lock#

void sl_hal_wdog_lock (WDOG_TypeDef * wdog)

Lock the watchdog configuration.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to WDOG peripheral register block.

This prevents errors from overwriting the WDOG configuration, possibly disabling it. Only a reset can unlock the WDOG configuration once locked.

If the LFRCO or LFXO clocks are used to clock WDOG, consider using the option of inhibiting those clocks to be disabled. See the #WDOG_INIT_DEFAULT initialization structure.

Note

This function modifies the WDOG 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.

sl_hal_wdog_wait_sync#

void sl_hal_wdog_wait_sync (WDOG_TypeDef * wdog)

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

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to WDOG peripheral register block.

sl_hal_wdog_wait_ready#

void sl_hal_wdog_wait_ready (WDOG_TypeDef * wdog)

Wait for the watchdog to be completely disabled after calling sl_hal_wdog_disable().

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to WDOG peripheral register block.

sl_hal_wdog_unlock#

void sl_hal_wdog_unlock (WDOG_TypeDef * wdog)

Unlock the watchdog configuration.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to WDOG peripheral register block.

Note that this function will have no effect on devices where a reset is the only way to unlock the watchdog.

sl_hal_wdog_clear_interrupts#

void sl_hal_wdog_clear_interrupts (WDOG_TypeDef * wdog, uint32_t flags)

Clear one or more pending watchdog interrupts.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.
uint32_t	[in]	flags	WDOG interrupt sources to clear. Use a set of interrupt flags OR-ed together to clear multiple interrupt sources.

sl_hal_wdog_disable_interrupts#

void sl_hal_wdog_disable_interrupts (WDOG_TypeDef * wdog, uint32_t flags)

Disable one or more watchdog interrupts.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.
uint32_t	[in]	flags	WDOG interrupt sources to disable. Use a set of interrupt flags OR-ed together to disable multiple interrupt.

sl_hal_wdog_enable_interrupts#

void sl_hal_wdog_enable_interrupts (WDOG_TypeDef * wdog, uint32_t flags)

Enable one or more watchdog interrupts.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.
uint32_t	[in]	flags	WDOG interrupt sources to enable. Use a set of interrupt flags OR-ed together to set multiple interrupt.

Note

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

sl_hal_wdog_get_pending_interrupts#

uint32_t sl_hal_wdog_get_pending_interrupts (WDOG_TypeDef * wdog)

Get pending watchdog interrupt flags.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Returns

Pending WDOG interrupt sources. Returns a set of interrupt flags OR-ed together for the interrupt sources set.

Note

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

sl_hal_wdog_get_enabled_pending_interrupts#

uint32_t sl_hal_wdog_get_enabled_pending_interrupts (WDOG_TypeDef * wdog)

Get enabled and pending watchdog interrupt flags.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Returns

Pending and enabled WDOG interrupt sources. Returns a set of interrupt flags OR-ed together for the interrupt sources set.

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

sl_hal_wdog_set_interrupts#

void sl_hal_wdog_set_interrupts (WDOG_TypeDef * wdog, uint32_t flags)

Set one or more pending watchdog interrupts from SW.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.
uint32_t	[in]	flags	WDOG interrupt sources to set to pending. Use a set of interrupt flags (WDOG_IFS_nnn).

sl_hal_wdog_is_enabled#

bool sl_hal_wdog_is_enabled (WDOG_TypeDef * wdog)

Get enabled status of the watchdog.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Returns

True if Watchdog is enabled, false otherwise.

sl_hal_wdog_is_locked#

bool sl_hal_wdog_is_locked (WDOG_TypeDef * wdog)

Get locked status of the watchdog.

Parameters

Type	Direction	Argument Name	Description
WDOG_TypeDef *	[in]	wdog	Pointer to the WDOG peripheral register block.

Returns

True if Watchdog is locked, false otherwise.