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How to send SAADC output to BLE device via SPI protocol?

I am trying to share ADC output to Bluetooth device. But issue is as I am getting SAADC output via SPI protocol. 

Now i have added SAADC+SPI in BLE app uart example, So when i call SPI function in main program  Bluetooth stops advertising again when i comment SPI function call then Bluetooth starts advertising. So please look after the code i have attached.

Why Bluetooth stops advertising when SPI function is called? Even  different TIMER i have defined, TIMER 2 but still I am finding issue.

Please suggest as I am trying to resolve this issue from 1week and its urgent.

#define SPI_INSTANCE  1 /**< SPI instance index. */
static const nrf_drv_spi_t spi = NRF_DRV_SPI_INSTANCE(SPI_INSTANCE);  /**< SPI instance. */
static volatile bool spi_xfer_done;  /**< Flag used to indicate that SPI instance completed the transfer. */

//#define TEST_STRING "Nordic"
static uint8_t       m_tx_buf[2];           /**< TX buffer. */
static uint8_t       m_rx_buf[40];    /**< RX buffer. */
//static const uint8_t m_length = sizeof(m_tx_buf);        /**< Transfer length. */


/**
 * @brief SPI user event handler.
 * @param event
 */
void spi_event_handler(nrf_drv_spi_evt_t const * p_event)
{
   spi_xfer_done = true;
	
		NRF_LOG_INFO(" Sent %d bytes: ", p_event->data.done.tx_length);
		for(int i=0; i< p_event->data.done.tx_length;i++)
		{
				NRF_LOG_INFO(" ;(0x%x); ",p_event->data.done.p_tx_buffer[i], p_event->data.done.p_tx_buffer[i]);
		}
		//NRF_LOG_INFO("\r\n");
		NRF_LOG_INFO(" Received %d bytes: ", p_event->data.done.rx_length);
		 for(int i=0; i< p_event->data.done.rx_length;i++)
		{
				NRF_LOG_INFO(" ;(0x%x); ",p_event->data.done.p_rx_buffer[i], p_event->data.done.p_rx_buffer[i]);
			nrf_delay_ms(5);
		}
		//NRF_LOG_INFO("\r\n\n");
}


void spi_con(void)
{
	
 nrf_gpio_cfg_output(18); //Configure pin 18 as output

 NRF_CLOCK->TASKS_HFCLKSTART = 1; //Start high frequency clock
 while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
 {
      //Wait for HFCLK to start
 }
 NRF_CLOCK->EVENTS_HFCLKSTARTED = 0; //Clear event
 
 
 //Configure GPIOTE to toggle pin 18 
 NRF_GPIOTE->CONFIG[0] = GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos |
                         GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos |
                         18 << GPIOTE_CONFIG_PSEL_Pos | 
                         GPIOTE_CONFIG_OUTINIT_Low << GPIOTE_CONFIG_OUTINIT_Pos;
 
 //Configure timer
 NRF_TIMER1->PRESCALER = 3;
 NRF_TIMER1->CC[0] = 1;  // Adjust the output frequency by adjusting the CC.
 NRF_TIMER1->SHORTS = TIMER_SHORTS_COMPARE0_CLEAR_Enabled << TIMER_SHORTS_COMPARE0_CLEAR_Pos;
 NRF_TIMER1->TASKS_START = 1;
 
 //Configure PPI
 NRF_PPI->CH[0].EEP = (uint32_t) &NRF_TIMER1->EVENTS_COMPARE[0];
 NRF_PPI->CH[0].TEP = (uint32_t) &NRF_GPIOTE->TASKS_OUT[0];
 
 NRF_PPI->CHENSET = PPI_CHENSET_CH0_Enabled << PPI_CHENSET_CH0_Pos;
	
    LEDS_CONFIGURE(BSP_LED_0_MASK);
    LEDS_OFF(BSP_LED_0_MASK);
	
	
	
		nrf_drv_spi_config_t spi_config = NRF_DRV_SPI_DEFAULT_CONFIG;
    spi_config.ss_pin   = SPI_SS_PIN;
    spi_config.miso_pin = SPI_MISO_PIN;
    spi_config.mosi_pin = SPI_MOSI_PIN;
    spi_config.sck_pin  = SPI_SCK_PIN;
    APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, spi_event_handler, NULL));

    NRF_LOG_INFO("SPI example started.");


        // Reset rx buffer and transfer done flag
        memset(m_rx_buf, 0, 40);
        spi_xfer_done = false;

			  m_tx_buf[0]=0x0d;
			
			
        APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, m_tx_buf, 2, m_rx_buf, 40));
	
	
	
        while (!spi_xfer_done)
        {
            __WFE();
        }
	
			
}

#define SAMPLES_IN_BUFFER 20
volatile uint8_t state = 1;
static  int   value;
static const nrf_drv_timer_t m_timer = NRF_DRV_TIMER_INSTANCE(2);
static nrf_saadc_value_t     m_buffer_pool[2][SAMPLES_IN_BUFFER];

static nrf_ppi_channel_t     m_ppi_channel;
static uint32_t              m_adc_evt_counter;


void timer_handler(nrf_timer_event_t event_type, void * p_context)
{

}


void saadc_sampling_event_init(void)
{
    ret_code_t err_code;

    err_code = nrf_drv_ppi_init();
    APP_ERROR_CHECK(err_code);

    nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
    timer_cfg.bit_width = NRF_TIMER_BIT_WIDTH_32;
    err_code = nrf_drv_timer_init(&m_timer, &timer_cfg, timer_handler);
    APP_ERROR_CHECK(err_code);

    /* setup m_timer for compare event every 400ms */
    uint32_t ticks = nrf_drv_timer_ms_to_ticks(&m_timer, 100);
    nrf_drv_timer_extended_compare(&m_timer,
                                   NRF_TIMER_CC_CHANNEL0,
                                   ticks,
                                   NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
                                   false);
    nrf_drv_timer_enable(&m_timer);

    uint32_t timer_compare_event_addr = nrf_drv_timer_compare_event_address_get(&m_timer,
                                                                                NRF_TIMER_CC_CHANNEL0);
    uint32_t saadc_sample_task_addr   = nrf_drv_saadc_sample_task_get();

    /* setup ppi channel so that timer compare event is triggering sample task in SAADC */
    err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_drv_ppi_channel_assign(m_ppi_channel,
                                          timer_compare_event_addr,
                                          saadc_sample_task_addr);
    APP_ERROR_CHECK(err_code);
}


void saadc_sampling_event_enable(void)
{
    ret_code_t err_code = nrf_drv_ppi_channel_enable(m_ppi_channel);

    APP_ERROR_CHECK(err_code);
}


void saadc_callback(nrf_drv_saadc_evt_t const * p_event)
{
    if (p_event->type == NRF_DRV_SAADC_EVT_DONE)
    {
        ret_code_t err_code;
				
        err_code = nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer, SAMPLES_IN_BUFFER);
        APP_ERROR_CHECK(err_code);
      
        int i;
        NRF_LOG_INFO("ADC event number: %d", (int)m_adc_evt_counter);

        for (i = 0; i < SAMPLES_IN_BUFFER; i++)
        {
					
					value= p_event->data.done.p_buffer[i];
          NRF_LOG_INFO("%d ",value);
        }
				//uint16_t length = (uint16_t)index;

			ble_nus_data_send(&m_nus,(uint8_t *)value,NULL,m_conn_handle);
        m_adc_evt_counter++;
    }
}


void saadc_init(void)
{
    ret_code_t err_code;
    nrf_saadc_channel_config_t channel_config =
     NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_AIN0);
    err_code = nrf_drv_saadc_init(NULL, saadc_callback);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_drv_saadc_channel_init(0, &channel_config);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAMPLES_IN_BUFFER);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1], SAMPLES_IN_BUFFER);
    APP_ERROR_CHECK(err_code);
}

I am not getting whats wrong in code please suggest.

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