HAL Timer

Classes
struct	hal_timer

Functions
int	hal_timer_init (int timer_num, void *cfg)
int	hal_timer_deinit (int timer_num)
int	hal_timer_config (int timer_num, uint32_t freq_hz)
uint32_t	hal_timer_get_resolution (int timer_num)
uint32_t	hal_timer_read (int timer_num)
int	hal_timer_delay (int timer_num, uint32_t ticks)
int	hal_timer_set_cb (int timer_num, struct hal_timer *tmr, hal_timer_cb cb_func, void *arg)
int	hal_timer_start (struct hal_timer *tmr, uint32_t ticks)
int	hal_timer_start_at (struct hal_timer *tmr, uint32_t tick)
int	hal_timer_stop (struct hal_timer *tmr)

Detailed Description

Function Documentation

hal_timer_config()

int hal_timer_config	(	int	timer_num,
		uint32_t	freq_hz
	)

Config a HW timer at the given frequency and start it. If the exact frequency is not obtainable the closest obtainable frequency is set.

Parameters

timer_num	The number of the HW timer to configure
freq_hz	The frequency in Hz to configure the timer at

Returns

0 on success, non-zero error code on failure

hal timer config

Configure a timer to run at the desired frequency. This starts the timer.

Parameters

timer_num
freq_hz

Returns

int

hal_timer_deinit()

int hal_timer_deinit

(

int

timer_num

)

Un-initialize a HW timer.

Parameters

timer_num

The number of the HW timer to un-initialize

hal timer deinit

De-initialize a HW timer.

Parameters

timer_num

Returns

int

hal_timer_delay()

int hal_timer_delay	(	int	timer_num,
		uint32_t	ticks
	)

Perform a blocking delay for a number of ticks.

Parameters

timer_num	The timer number to use for the blocking delay
ticks	The number of ticks to delay for

Returns

0 on success, non-zero error code on failure

hal timer delay

Blocking delay for n ticks

Parameters

timer_num
ticks

Returns

int 0 on success; error code otherwise.

hal_timer_get_resolution()

uint32_t hal_timer_get_resolution

(

int

timer_num

)

Returns the resolution of the HW timer. NOTE: the frequency may not be obtainable so the caller can use this to determine the resolution. Returns resolution in nanoseconds. A return value of 0 indicates an invalid timer was used.

Parameters

timer_num

The number of the HW timer to get resolution for

Returns

The resolution of the timer

hal timer get resolution

Get the resolution of the timer. This is the timer period, in nanoseconds

Parameters

timer_num

Returns

uint32_t The

hal_timer_init()

int hal_timer_init	(	int	timer_num,
		void *	cfg
	)

Initialize a HW timer.

Parameters

timer_num	The number of the HW timer to initialize
cfg	Hardware specific timer configuration. This is passed from BSP directly to the MCU specific driver.

hal timer irq handler

Generic HAL timer irq handler.

Parameters

tmr	hal timer irq handler

This is the global timer interrupt routine. hal timer init

Initialize platform specific timer items

Parameters

timer_num	Timer number to initialize
cfg	Pointer to platform specific configuration

Returns

int 0: success; error code otherwise

hal_timer_read()

uint32_t hal_timer_read

(

int

timer_num

)

Returns the HW timer current tick value

Parameters

timer_num

The HW timer to read the tick value from

Returns

The current tick value

hal timer read

Returns the timer counter. NOTE: if the timer is a 16-bit timer, only the lower 16 bits are valid. If the timer is a 64-bit timer, only the low 32-bits are returned.

Returns

uint32_t The timer counter register.

hal_timer_set_cb()

int hal_timer_set_cb	(	int	timer_num,
		struct hal_timer *	timer,
		hal_timer_cb	cb_func,
		void *	arg
	)

Set the timer structure prior to use. Should not be called if the timer is running. Must be called at least once prior to using timer.

Parameters

timer_num	The number of the HW timer to configure the callback on
tmr	The timer structure to use for this timer
cb_func	The timer callback to call when the timer fires
arg	An opaque argument to provide the timer callback

Returns

0 on success, non-zero error code on failure.

Initialize the HAL timer structure with the callback and the callback argument. Also initializes the HW specific timer pointer.

Parameters

cb_func

Returns

int

hal_timer_start()

int hal_timer_start	(	struct hal_timer *	tmr,
		uint32_t	ticks
	)

Start a timer that will expire in 'ticks' ticks. Ticks cannot be 0

Parameters

tmr	The timer to start
ticks	The number of ticks to expire the timer in

Returns

0 on success, non-zero error code on failure.

hal_timer_start_at()

int hal_timer_start_at	(	struct hal_timer *	tmr,
		uint32_t	tick
	)

Start a timer that will expire when the timer reaches 'tick'. If tick has already passed the timer callback will be called "immediately" (at interrupt context).

Parameters

tmr	The timer to start
tick	The absolute tick value to fire the timer at

Returns

0 on success, non-zero error code on failure.

hal_timer_stop()

int hal_timer_stop

(

struct hal_timer *

timer

)

Stop a currently running timer; associated callback will NOT be called

Parameters

tmr	The timer to stop

hal timer stop

Stop a timer.

Parameters

timer

Returns

int