App Timer not run with PWM driver simultaneously

[Giang]

Hello,

I use NRF52832 with SDK 17.0.2.

I run app timer and pwm driver independently ok.

I merged App timer with PWM Driver. But only PWM run, I can't make app timer app run. If I comment PWM driver so app timer run.

This my code

APP_TIMER_DEF(m_repeated_timer_id); 

/**@brief Timeout handler for the repeated timer.
 */
static void repeated_timer_handler(void * p_context)
{
    nrf_gpio_pin_toggle(LED_2);
}

/**@brief Function starting the internal LFCLK oscillator.
 *
 * @details This is needed by RTC1 which is used by the Application Timer
 *          (When SoftDevice is enabled the LFCLK is always running and this is not needed).
 */
static void lfclk_request(void)
{
    ret_code_t err_code = nrf_drv_clock_init();
    APP_ERROR_CHECK(err_code);
    nrf_drv_clock_lfclk_request(NULL);
}

static void create_timers()
{
    ret_code_t err_code;

    // Create timers
    err_code = app_timer_create(&m_repeated_timer_id,
                                APP_TIMER_MODE_REPEATED,
                                repeated_timer_handler);
    APP_ERROR_CHECK(err_code);
}

int main(void)
{
		lfclk_request();
    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
    NRF_LOG_DEFAULT_BACKENDS_INIT();

    pwm_init(LED_1, LED_3);
		
		nrf_gpio_cfg_output(LED_2);

		APP_ERROR_CHECK(app_timer_init());
		create_timers();
		int err_code = app_timer_start(m_repeated_timer_id, APP_TIMER_TICKS(200), NULL);
		APP_ERROR_CHECK(err_code); 
    for (;;)
    {
        // Wait for an event.
        __WFE();

        // Clear the event register.
        __SEV();
        __WFE();

        NRF_LOG_FLUSH();
    }
}

and my PWM Init

static nrf_drv_pwm_t m_pwm0 = NRF_DRV_PWM_INSTANCE(0);

// This is for tracking PWM instances being used, so we can unintialize only
// the relevant ones when switching from one demo to another.
#define USED_PWM(idx) (1UL << idx)
static uint8_t m_used = 0;

static uint16_t const              m_pwm_top  = 255;
static uint16_t const              m_pwm_step = 1;
static nrf_pwm_values_individual_t channel;
int count = 0;

static nrf_pwm_sequence_t const    m_pwm_seq =
{
    .values.p_individual = &channel,
    .length              = NRF_PWM_VALUES_LENGTH(channel),
    .repeats             = 0,
    .end_delay           = 0
};

static void pwm_handler(nrf_drv_pwm_evt_type_t event_type)
{
	if (event_type == NRF_DRV_PWM_EVT_FINISHED)
	{
				static bool down = false; 
				int value = channel.channel_0;
        if (down)
        {
            value -= m_pwm_step;
            if (value == 0)
            {
                down = false;
            }
        }
        else
        {
            value += m_pwm_step;
            if (value >= m_pwm_top)
            {
                down = true;
            }
        }
        channel.channel_0 = value;
				channel.channel_1 = value;
				nrf_delay_ms(10);
	}
}

void pwm_init(int pin1, int pin2)
{
    nrf_drv_pwm_config_t const config0 =
    {
        .output_pins =
        {
            pin1 | NRF_DRV_PWM_PIN_INVERTED, // channel 0
            pin2 | NRF_DRV_PWM_PIN_INVERTED, // channel 1
        },
        .irq_priority = _PRIO_APP_LOWEST,
        .base_clock   = NRF_PWM_CLK_1MHz,
        .count_mode   = NRF_PWM_MODE_UP,
        .top_value    = m_pwm_top,
        .load_mode    = NRF_PWM_LOAD_INDIVIDUAL,
        .step_mode    = NRF_PWM_STEP_AUTO
    };
    APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, pwm_handler));

    channel.channel_0 = 0;
    channel.channel_1 = 0;

    (void)nrf_drv_pwm_simple_playback(&m_pwm0, &m_pwm_seq, 1,
                                      NRFX_PWM_FLAG_LOOP);
}

Please show me why and how to fix.

Thank you

[Mttrinh]

Hi,

Can you try debug the code and see if you are getting any error codes when running both at the same time? Do you have any logs?

[Giang]

Hi,

If I change 

APP_ERROR_CHECK(app_timer_init());
create_timers();
int err_code = app_timer_start(m_repeated_timer_id, APP_TIMER_TICKS(200), NULL);
APP_ERROR_CHECK(err_code);
pwm_init(LED_1, LED_3);

It run PWM and Timer but 

pwm_init(LED_1, LED_3);
APP_ERROR_CHECK(app_timer_init());
create_timers();
int err_code = app_timer_start(m_repeated_timer_id, APP_TIMER_TICKS(200), NULL);
APP_ERROR_CHECK(err_code);

It only run PWM.

And I don't understand why.

[Mttrinh]

Hi,

Seems like you worked it out?

Not too sure why the order would be an issue. When you get initiate the PWM first, what do you get as return code on app_timer_init() and app_timer_start()? Are they called successfully?

[Giang]

yes, it success, if it error, program will hang. But it run PWM normal, it only not run timer.

[Giang]

This my code: 

PROJECT

[Mttrinh]

Just to clarify:

If you call pwm_init() after app_timer_init() and app_timer_start, then both PWM and app timer works fine. But when it is called before then only PWM works. Is this correct? What kinda error do you get when program hang?