led softblink example with freertos rtc

RE: led softblink example with freertos rtc

inghowe83 — Wed, 28 Nov 2018 08:33:19 GMT

RE: led softblink example with freertos rtc

Susheel Nuguru — Tue, 27 Nov 2018 08:50:48 GMT

you need to understand in detail about what each member in the below config means

nrf_drv_pwm_config_t const config0 =

The below four will decide the tone of your softblink

        .count_mode   = NRF_PWM_MODE_UP,
        .top_value    = m_demo1_top,
        .load_mode    = NRF_PWM_LOAD_INDIVIDUAL,
        .step_mode    = NRF_PWM_STEP_AUTO

RE: led softblink example with freertos rtc

inghowe83 — Mon, 26 Nov 2018 23:30:28 GMT

Thank you Susheel Nuguru

May I know which is the parameters to affect the blink interval and pwm freq in this sample code?

Thanks

RE: led softblink example with freertos rtc

Susheel Nuguru — Fri, 23 Nov 2018 11:54:27 GMT

There is no problem using freeRTOS + softdevice. I think the problem for you is to use simulated PWM using app_timer.

You need to use real PWM instead of a simulated one to solve . I have edited your example to use PWM instead of app_timer and i can see the softblink now. If you want to understand how PWM works, I would recommend you to read its spec from the product specification.

devzone.nordicsemi.com/.../blinky_5F00_PWM_5F00_freertos.rar

RE: led softblink example with freertos rtc

inghowe83 — Fri, 23 Nov 2018 07:52:12 GMT

Hi Susheel Nuguru

Thanks for your input. I still very new to softdevice and FreeRTOS, the pain part is our customer needs FreeRTOS while supporting softdevices api. Do nordic have any other solutions to make softblink workable under freertos rtc environment?

RE: led softblink example with freertos rtc

Susheel Nuguru — Thu, 22 Nov 2018 14:16:53 GMT

[quote user="inghowe83"]What are the main difference between non freertos vs freertos app timer?[/quote]

This is a good question.The app_timer_freertos and app_timer does not exactly behave similar.

The timers scheduling mechanism is completely different and the way they are queued and their linked list nature is completely different. But I am very surprised by the difference in behavior here. I did not expect them to show this big different. But there seems to be a huge difference.

In FreeRTOS it is not possible to restart an already running timer (without stopping and restarting) but in app_timer we can do that easily. This difference could be explain a bit of this weird behavior.

RE: led softblink example with freertos rtc

inghowe83 — Thu, 22 Nov 2018 00:38:04 GMT

Thanks Susheel Nuguru, I tested the solutions on my DK board. The led blink too fast(don't looks like a softblink) and it will stop blinking intermittently before it start blink again. Was it related to the FreeRTOS timer conflict with the softblink? Do you know whereI could look into? What are the main difference between non freertos vs freertos app timer? Is the nordic softbolink mechanism based on different rtc timer from freertos?

I tried use debug-break during the part when the led stop blinking and it stopped at the below code (port_cmsis_systick.c), tickless idle seem to interfere with the softblink feature.

devzone.nordicsemi.com/.../VID_5F00_20181122_5F00_074427.mp4

RE: led softblink example with freertos rtc

Susheel Nuguru — Wed, 21 Nov 2018 12:41:49 GMT

You main function is not complete. You are depending to use freeRTOS timers without actually starting the kernel. Change your main() function to below

int main(void)
{
    ret_code_t err_code;
    lfclk_init();

    // Start APP_TIMER to generate timeouts.
    err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    const led_sb_init_params_t led_sb_init_param = LED_SB_INIT_DEFAULT_PARAMS(LEDS_MASK);

    err_code = led_softblink_init(&led_sb_init_param);
    APP_ERROR_CHECK(err_code);

    err_code = led_softblink_start(LEDS_MASK);
    APP_ERROR_CHECK(err_code);

    
    /* Activate deep sleep mode */
    SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;

    /* Start FreeRTOS scheduler. */
    vTaskStartScheduler();
    
    while (true)
    {
        __WFE();
    }
}

RE: led softblink example with freertos rtc

inghowe83 — Mon, 19 Nov 2018 01:41:36 GMT

Hi There,

I have attached my example, what I did is tried to use the softblink main.c directly on the Blink RTC FreeRTOS example, mind help me review is what I have broken? Thanks.

devzone.nordicsemi.com/.../blinky_5F00_rtc_5F00_freertos.zip

RE: led softblink example with freertos rtc

inghowe83 — Fri, 16 Nov 2018 08:29:36 GMT

Hi Susheel Nuguru

Thanks for the quick reply. I did try migrate the soft_blink example into the blinky rtc freertos example. Tried and found out the softblink doesn't work, all the led is turn on but it never have softblink effect. I not sure does it related to using app_timer_freertos.c? My custom board works perfectly using the default softblink example which is based on non freertos app_timer.c.

RE: led softblink example with freertos rtc

Susheel Nuguru — Thu, 15 Nov 2018 12:05:49 GMT

Ideally, you need to delete app_timer.c file from your project.

You only should be using app_timer_freertos.c only. Both of them are API compatible, so you should not have problems removing app_timer.c from your project and soft_blink example will then use app_timer_freertos API correctly