SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

ricardo vasquez rossi — Thu, 21 Feb 2019 00:50:30 GMT

Hi Jørgen

It works perfect!!!

Thanks...

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

Jørgen Holmefjord — Tue, 19 Feb 2019 15:50:58 GMT

In that case there is no need to use ppi to trigger the sample task. My recommendation would be to setup the buffer in the nus_data_handler() and trigger nrf_drv_saadc_sample() once. The SAADC should then fill the buffer and call the saadc_callback when it is done. If you avoid setting up new buffers in the callback, the SAADC should not continue sampling.

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

ricardo vasquez rossi — Tue, 19 Feb 2019 14:21:36 GMT

Hi Jørgen

I configured the continuous Sampling, because I read 1024 datas (with the sample rate of 200.000 Hz), I used it in the FFT (fast furier transfor) to get the sound frequency spectrum...

Could I stop the SAADC execute

"NRF_SAADC->SAMPLERATE = (0 << 12);"

and

"saadc_sampling_event_disable(); "

in the main loop?

0 = Rate is controlled from SAMPLE task

NRF_SAADC->SAMPLERATE = (0 << 12); // 0 = Rate is controlled from SAMPLE task

Thanks for your support..

Ricardo

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

Jørgen Holmefjord — Tue, 19 Feb 2019 09:01:58 GMT

Try removing these two lines from your saadc_init function:

NRF_SAADC->SAMPLERATE  =  (1 << 12);                                          // Timer mode  
NRF_SAADC->SAMPLERATE  |= 80;                                                 // 16MHz / 80 counts = 200 000 triggers per second

These lines will configure the SAADC in continuous sampling mode, overriding the PPI sample task.

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

ricardo vasquez rossi — Tue, 19 Feb 2019 03:29:22 GMT

Hi Jørgen

you are right.. something inside happend of nus_data_handler but the SAADC_CALLBACK doesnt run..

as your recomendation if enable the SAADC outside of nus_data_handler the saadc start working..

Resuming I change the following in the code..

static void nus_data_handler(ble_nus_evt_t * p_evt)
{
  
  if (p_evt->type == BLE_NUS_EVT_RX_DATA)
  {
    Bla.. bla..
    
    bla..  bla...  bla...
    
    
    if(p_evt->params.rx_data.p_data[0] == '!')
    {      
      SAACD_Ultrasound_Enable = true;
                   
    }
  }
}


And in the main loop

for (;;)
  {
    if (SAACD_Ultrasound_Enable)
    {
      Datos_Capturados_Ultrasonido = false;
      Capturar_datos_SAADC = true;
      SAACD_Ultrasound_Enable = false;

      saadc_sampling_event_enable();

      //RealFFT_Instance.fftLenReal= Total_samples;

      
      while (!Datos_Capturados_Ultrasonido){}
      saadc_sampling_event_disable();
      Datos_Capturados_Ultrasonido = false;
      nrf_drv_timer_disable(&m_timer);
      
      nrf_drv_saadc_uninit();
      
      nrf_drv_saadc_channel_uninit(0);
     }
    idle_state_handle();

  }
}

NOW .. I have the following problem..

I enabled the Saadc with " saadc_sampling_event_enable(); "

and the saadc_callback (function) Starting..

Why I cant stop it with saadc_sampling_event_disable(); ?

void saadc_sampling_event_disable(void)
{
  ret_code_t err_code = nrf_drv_ppi_channel_disable(m_ppi_channel);
  
  APP_ERROR_CHECK(err_code);
}

Because when I execute saadc_sampling_event_disable();

the function saadc_callback still in loop...I know because I send a printf a message to terminal..

ONLY i can stop the SAADC when I kill everything.. doing uninit..

nrf_drv_saadc_uninit();
nrf_drv_saadc_channel_uninit(0);

If I execute Saacd_init() the program goes to Hardfault..

is there any simple way to enable and disable again the SAADC?

Thanks

Ricardo

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

ricardo vasquez rossi — Mon, 18 Feb 2019 17:25:06 GMT

Hi Jørgen

Thanks for your fast answer, YES the programs STUCK in ... while (!Datos_Capturados_Ultrasonido){}

I will do it...

thanks

Ricardo

RE: SAADC + BLE UART (NUS), The saadc_callback function doesnt execute.

Jørgen Holmefjord — Mon, 18 Feb 2019 16:26:09 GMT

Hi,

It could be some issue with priorities. Are you stuck at the line where you wait for Datos_Capturados_Ultrasonido? I would recommend that you exit the nus_data_handler while sampling, and disable sampling/ppi channel in saadc_callback or main context.

Best regards,
Jørgen