How to set PWM cycle to 10 seconds ?

[sthuang]

Hi,

I use SDK 10 pwm example (examples\peripheral\pwm) to modify the PWM cycle to 10s and duty cycle to 50%.

Code showed as below:

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int main(void)

{

ret_code_t err_code;

/* 2-channel PWM, 200Hz, output on DK LED pins. */

app_pwm_config_t pwm1_cfg = APP_PWM_DEFAULT_CONFIG_2CH(10000000L, BSP_LED_0, BSP_LED_1);

/* Switch the polarity of the second channel. */

pwm1_cfg.pin_polarity[1] = APP_PWM_POLARITY_ACTIVE_HIGH;

/* Initialize and enable PWM. */

err_code = app_pwm_init(&PWM1,&pwm1_cfg,pwm_ready_callback);

APP_ERROR_CHECK(err_code);

app_pwm_enable(&PWM1);

//uint32_t value;

while(true)

{

for (uint8_t i = 0; i < 40; ++i)

{

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

int main(void)
{
    ret_code_t err_code;
    
    /* 2-channel PWM, 200Hz, output on DK LED pins. */
    app_pwm_config_t pwm1_cfg = APP_PWM_DEFAULT_CONFIG_2CH(10000000L, BSP_LED_0, BSP_LED_1);
    
    /* Switch the polarity of the second channel. */
    pwm1_cfg.pin_polarity[1] = APP_PWM_POLARITY_ACTIVE_HIGH;
    
    /* Initialize and enable PWM. */
    err_code = app_pwm_init(&PWM1,&pwm1_cfg,pwm_ready_callback);
    APP_ERROR_CHECK(err_code);
    app_pwm_enable(&PWM1);
    
    //uint32_t value;
    while(true)
    {
        
        for (uint8_t i = 0; i < 40; ++i)
        {
            //value = (i < 20) ? (i * 5) : (100 - (i - 20) * 5);
            
            ready_flag = false;
            
            /* Set the duty cycle - keep trying until PWM is ready... */
            while (app_pwm_channel_duty_set(&PWM1, 0, 50) == NRF_ERROR_BUSY);
            
            /* ... or wait for callback. */
            while(!ready_flag);
            APP_ERROR_CHECK(app_pwm_channel_duty_set(&PWM1, 1, 50));
            nrf_delay_ms(25);
        }
    }
    
}

But the PWM cycle seem only around 3 seconds. Can it possible change PWM cycle time to 10s ? If can, how to do so?

Thanks.