Timer Class Reference

Timer implementation using the us ticker. More...

#include <Timer.h>

Inheritance diagram for Timer:

Public Member Functions
void	start ()
	Start the timer.
void	stop ()
	Stop the timer.
void	reset ()
	Reset the timer to 0.
float	read () const
	Get the time passed in seconds.
int	read_ms () const
	Get the time passed in milliseconds.
int	read_us () const
	Get the time passed in microseconds.
	operator float () const
	An operator shorthand for read()
us_timestamp_t	read_high_resolution_us () const
	Get (in a high resolution type) the time passed in microseconds.
std::chrono::microseconds	elapsed_time () const
	Get the time passed as chrono microseconds.

Detailed Description

Timer implementation using the us ticker.

Locks deep sleep while actively running.

Example:

// Count the time to toggle an LED
 
#include "mbed.h"
#include <cinttypes>
 
Timer timer;
DigitalOut led(LED1);
 
int main() {
    timer.start();
    const auto begin = timer.elapsed_time();
    led = !led;
    const auto end = timer.elapsed_time();
    printf("Toggling the led takes %" PRIi64 " us", (end - begin).count());
}

Note

When constructed, a Timer is stopped and reset to zero time.

Synchronization level: Interrupt safe

Definition at line 167 of file Timer.h.

Member Function Documentation

start()

void start ( )

inherited

Start the timer.

Will lock deep sleep if this is a Timer instance

stop()

void stop ( )

inherited

Stop the timer.

Will release the deep sleep lock if this is a Timer instance

reset()

void reset ( )

inherited

Reset the timer to 0.

If it was already running, it will continue

read()

float read ( ) const

inherited

Get the time passed in seconds.

Returns

Time passed in floating-point seconds

Deprecated:

"Floating point operators should normally be avoided for code size. If really needed, you can use `duration<float>{elapsed_time()}.count()`" [since "mbed-os-6.0.0" ]

read_ms()

int read_ms ( ) const

inherited

Get the time passed in milliseconds.

Returns

Time passed in integer milliseconds

Deprecated:

"Use the Chrono-based elapsed_time method. If integer milliseconds are needed, you can use `duration_cast<milliseconds>(elapsed_time()).count()`" [since "mbed-os-6.0.0" ]

read_us()

int read_us ( ) const

inherited

Get the time passed in microseconds.

Returns

Time passed in integer microseconds

Warning

Limited to 31 bits – will not return correct values for times larger than about 35 minutes. Use read_high_resolution_us or elapsed_time instead as they are not vulnerable to this problem.

Deprecated:

"Use the Chrono-based elapsed_time method. If integer microseconds are needed, you can use `elapsed_time().count()`" [since "mbed-os-6.0.0" ]

operator float()

operator float ( ) const

inherited

An operator shorthand for read()

Returns

Time passed in floating-point seconds

Deprecated:

"Floating point operators should normally be avoided for code size. If really needed, you can use `duration<float>{elapsed_time()}.count()`" [since "mbed-os-6.0.0" ]

read_high_resolution_us()

us_timestamp_t read_high_resolution_us ( ) const

inherited

Get (in a high resolution type) the time passed in microseconds.

Returns

Time passed as 64-bit microseconds.

Deprecated:

"Use the Chrono-based elapsed_time method. If integer microseconds are needed, you can use `elapsed_time().count()`" [since "mbed-os-6.0.0" ]

elapsed_time()

std::chrono::microseconds elapsed_time ( ) const

inherited

Get the time passed as chrono microseconds.

Returns

Time passed as std::chrono::microseconds