WDT: Watchdog Timer

Overview

The MCUXpresso SDK provides a peripheral driver for the Watchdog Timer module of MCUXpresso SDK devices.

Typical use case

Example use of WDT API. Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/wdt

Data Structures
struct	wdt_config_t
	WDT configuration structure. More...

Macros
#define	FSL_WDT_DRIVER_VERSION   (MAKE_VERSION(2, 1, 0))
	Defines WDT driver version 2.1.0. More...

Typedefs
typedef void(*	wdg_callback_t )(void)
	Callback function when WDT interrupt happens.

Functions
void	WDT_Init (TIMERS_Type *base, const wdt_config_t *config)
	Initialize the WDT. More...
void	WDT_Deinit (TIMERS_Type *base)
	De-initialize the WDT. More...
void	WDT_StartTimer (TIMERS_Type *base, uint32_t timeoutCount)
	start wdt timer. More...
void	WDT_StopTimer (TIMERS_Type *base)
	stop wdt timer. More...
static void	WDT_SetInterruptThreshold (TIMERS_Type *base, uint32_t threshold)
	Sets the WDT triggerthreshold. More...
static void	WDT_SetTimeoutStatus (TIMERS_Type *base)
	This function force sets the timeout status flag, even when WDT counter does not reach threshold. More...
static void	WDT_ClearTimeoutStatus (TIMERS_Type *base)
	Timer clear timeout status. More...
static bool	WDT_GetTimeoutStatus (TIMERS_Type *base)
	WDT timeout status enable/disable. More...
static uint32_t	WDT_GetRemainCount (TIMERS_Type *base)
	WDT get wdt remain count. More...
static void	WDT_Feed (TIMERS_Type *base)
	Feed WDT timer. More...
void	WDT_HandleIRQ (TIMERS_Type *base)
	WDT IRQ handler. More...

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Data Structure Documentation

struct wdt_config_t

Data Fields
uint32_t	timeoutCount
	Timeout value set to register WDOG_TIMEOUT. More...
uint32_t	threshold
	Time threshold to trigger interrupt. More...
wdg_callback_t	callback
	Callback when interrupt happens. More...

Field Documentation

uint32_t wdt_config_t::timeoutCount

The maximum timeoutCount is 0x000FFFFF.

uint32_t wdt_config_t::threshold

wdg_callback_t wdt_config_t::callback

Macro Definition Documentation

#define FSL_WDT_DRIVER_VERSION   (MAKE_VERSION(2, 1, 0))

Function Documentation

void WDT_Init	(	TIMERS_Type *	base,
		const wdt_config_t *	config
	)

This function register the interrupt callback, set the interrupt counter threshold, and sets the timeout to start WDT.

Parameters

base	wdt base pointer.
config	The configuration.

void WDT_Deinit

(

TIMERS_Type *

base

)

This function stops the WDT, clears the interrupt flags, and unregisters the callback.

Parameters

base	wdt base pointer.

void WDT_StartTimer	(	TIMERS_Type *	base,
		uint32_t	timeoutCount
	)

Parameters

base	wdt base pointer.
timeoutCount	the initial timeout count of the timer. The total timeout time is determined by (1 / timerCountingFreq_Hz) * timeoutCount.The maximum timeoutCount is 0x000FFFFF.

void WDT_StopTimer

(

TIMERS_Type *

base

)

Parameters

base	timer base pointer.

static void WDT_SetInterruptThreshold ( TIMERS_Type *  base, uint32_t  threshold  )

inlinestatic

The Watchdog timer includes a "timeout pre-emption" feature whereby the non-maskable interrupt output intreq_wdg_o is asserted high when the counter reaches the value specified in field WDOG_INT_THRESHOLD defined in register TIMERS_WDOG_TRIGGER_INT_REG.

Parameters

base	WDT peripheral base address
threshold	WDT triggerthreshold value.

static void WDT_SetTimeoutStatus ( TIMERS_Type *  base )

inlinestatic

Parameters

base	timer base pointer.

static void WDT_ClearTimeoutStatus ( TIMERS_Type *  base )

inlinestatic

Parameters

base	timer base pointer.
timer	the specific timer to be stop.

static bool WDT_GetTimeoutStatus ( TIMERS_Type *  base )

inlinestatic

Parameters

base	timer base pointer.

Return values

true	is the timer timeout, false is the timeout still not timeout.

static uint32_t WDT_GetRemainCount ( TIMERS_Type *  base )

inlinestatic

Parameters

base	timer base pointer.

static void WDT_Feed ( TIMERS_Type *  base )

inlinestatic

This is a mandatory step, if this function isn't called after enabling the WDT, WDT will ignore timeout errors and will not generate a WDT interrupt or reset the chip.

Parameters

base	WDT peripheral base address

void WDT_HandleIRQ

(

TIMERS_Type *

base

)

Call this function in the ISR.

Parameters

base	WDT peripheral base address