Hot to detect the GPIO status with Timer

[CY]

I would like to make a timer to check the GPIO status.

The current code is like below:

// Detect the event
void charge_event_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
	{
    if(action == GPIOTE_CONFIG_POLARITY_HiToLo  && pin == TYPE_C)
			{
                nrf_gpio_pin_set(LED_2);
			}
	if(action == GPIOTE_CONFIG_POLARITY_LoToHi  && pin == TYPE_C)
			{
				nrf_gpio_pin_clear(LED_2);
			}
}

	
void charge_init(void)
{
	uint32_t err_code;
	//Configure button with pullup and event on both high and low transition
    nrf_drv_gpiote_in_config_t config = GPIOTE_CONFIG_IN_SENSE_TOGGLE(false);
    config.pull = NRF_GPIO_PIN_PULLUP;
	
    err_code=nrf_drv_gpiote_in_init(TYPE_C, &config, charge_event_handler); 
    nrf_drv_gpiote_in_event_enable(TYPE_C, true);                  
	APP_ERROR_CHECK(err_code);
}

static void charge_meas_timeout_handler(void * p_context)
{
    UNUSED_PARAMETER(p_context);
	charge_init();
}

///////////////////////////////////////////////////////////////////////////////////
/**@brief Function for the Timer initialization.
 *
 * @details Initializes the timer module. This creates and starts application timers.
 */
static void timers_init(void)
{
    // Initialize timer module.
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    err_code = app_timer_create(&m_charge_timer_id,
                                APP_TIMER_MODE_REPEATED,
                                charge_meas_timeout_handler);
}

/**@brief Function for starting timers.
 */
static void application_timers_start(void)
{
    ret_code_t err_code;

	err_code = app_timer_start(m_charge_timer_id, CHARGE_MEAS_INTERVAL, NULL);
    APP_ERROR_CHECK(err_code);

}

I already checked that timer function is worked by implant the specific event into the charge_event_handler as below:

charge_event_handler(TYPE_C,GPIOTE_CONFIG_POLARITY_LoToHi );

But not sure how to make it switch from different event.

Or there is any smart way to make it?

[Ali Rumane]

Hi,

CY said:

But not sure how to make it switch from different event.

Not sure what you want to achieve or different event as in?

Are you disabling gpiote from some other function? It is being reinitialized every time a timeout occurs.

void charge_check_status(void)
{
    if (!nrf_gpio_pin_read(TYPE_C))
	{
		nrf_gpio_pin_set(LED_2);
	}
	else
	{
	    nrf_gpio_pin_clear(LED_2);
	}
}


static void application_timers_start(void)
{
    ret_code_t err_code;

	err_code = app_timer_start(m_charge_timer_id, CHARGE_MEAS_INTERVAL, NULL);
    APP_ERROR_CHECK(err_code);
}

static void charge_meas_timeout_handler(void * p_context)
{
    UNUSED_PARAMETER(p_context);
	charge_check_status();
}

static void timers_init(void)
{
    // Initialize timer module.
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    err_code = app_timer_create(&m_charge_timer_id,
                                APP_TIMER_MODE_REPEATED,
                                charge_meas_timeout_handler);
}


// Initialise the GPIO
void gpio_init(void)
{
    // LED_2 can be initialised here

    // Initialise TYPE_C as input
    nrf_gpio_cfg_input(TYPE_C , NRF_GPIO_PIN_PULLUP);
}

I have a simple code that reads pin status after a timeout occurs.

You can use gpiote with ppi in case you want it for your application. Do let me know if it works or what do you want to implement.

Regards

[CY]

Hi Ali,

I just tried your suggestion, and it work properly.

I am curious about what is the different between using GPIO and GPIOTE? Will it make power consumption different?

Honestly, I do not familiar with PPI why it could be used with GPIOTE or why it need? Does it have any benefit?

Thanks.

[Ali Rumane]

Hi,

Good to know it works!

If you have a button or wakeup interrupt from button/IC or similar case you can use GPIOTE which is a peripheral that generates events on pin state change or as configured.

You can look at posts and infocenter here to know more

Link Link Link

Peripherals can interact with tasks and events independent of CPU with Programmable peripheral interconnect (PPI). You can learn more about it here and in this post.

Do let us know if it helps or need some understanding.

Regards

(Note: I have sighted nRF52832 as an example. You can refer Product specification of your case.)