void conver_to_voltage(uint16_t sample_value)
{
		uint8_t battery_level = 0;
		uint16_t votage_mv = 0;
	  votage_mv = (uint16_t)((sample_value*0.6/4096)*1000*6);	
		battery_level = battery_level_in_percent(votage_mv);
//	  printf("votage=%d mv battery_level=%d\r\n",votage_mv,battery_level);
		ble_bas_battery_level_update(&m_bas,battery_level);	

}


void saadc_callback(nrf_drv_saadc_evt_t const * p_event)
{
    ret_code_t err_code;
    if (p_event->type == NRF_DRV_SAADC_EVT_DONE)                                                        //Capture offset calibration complete event
    {
        if((m_adc_evt_counter % SAADC_CALIBRATION_INTERVAL) == 0)                                  			//Evaluate if offset calibration should be performed. Configure the SAADC_CALIBRATION_INTERVAL constant to change the calibration frequency
        {
            nrf_drv_saadc_abort();                                                                      // Abort all ongoing conversions. Calibration cannot be run if SAADC is busy
            m_saadc_calibrate = true;                                                                   // Set flag to trigger calibration in main context when SAADC is stopped
				}
        
//        printf("ADC event number: %d\r\n",(int)m_adc_evt_counter);                                //Print the event number on UART

        for (int i = 0; i < p_event->data.done.size; i++)
        {
//            printf("%d\r\n", p_event->data.done.p_buffer[i]);                                     //Print the SAADC result on UART
						conver_to_voltage(p_event->data.done.p_buffer[i]);
				}
				
        
        if(m_saadc_calibrate == false)
        {
            err_code = nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer, SAADC_SAMPLES_IN_BUFFER);             //Set buffer so the SAADC can write to it again. 
            APP_ERROR_CHECK(err_code);
        }
        
        m_adc_evt_counter++;
  
    }
    else if (p_event->type == NRF_DRV_SAADC_EVT_CALIBRATEDONE)
    {
        
        err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAADC_SAMPLES_IN_BUFFER);             //Set buffer so the SAADC can write to it again. 
        APP_ERROR_CHECK(err_code);
        err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1], SAADC_SAMPLES_IN_BUFFER);             //Need to setup both buffers, as they were both removed with the call to nrf_drv_saadc_abort before calibration.
        APP_ERROR_CHECK(err_code);
        
 //       printf("SAADC calibration complete ! \r\n");                                              //Print on UART

        
    }
}
void saadc_init(void)
{
    ret_code_t err_code;
    nrf_drv_saadc_config_t saadc_config;
    nrf_saadc_channel_config_t channel_config;


	
    //Configure SAADC
    saadc_config.low_power_mode = true;                                                   //Enable low power mode.
    saadc_config.resolution = NRF_SAADC_RESOLUTION_12BIT;                                 //Set SAADC resolution to 12-bit. This will make the SAADC output values from 0 (when input voltage is 0V) to 2^12=2048 (when input voltage is 3.6V for channel gain setting of 1/6).
    saadc_config.oversample = SAADC_OVERSAMPLE;                                           //Set oversample to 4x. This will make the SAADC output a single averaged value when the SAMPLE task is triggered 4 times.
    saadc_config.interrupt_priority = APP_IRQ_PRIORITY_LOW;                               //Set SAADC interrupt to low priority.
	
    //Initialize SAADC
    err_code = nrf_drv_saadc_init(&saadc_config, saadc_callback);                         //Initialize the SAADC with configuration and callback function. The application must then implement the saadc_callback function, which will be called when SAADC interrupt is triggered
    APP_ERROR_CHECK(err_code);
		
    //Configure SAADC channel
    channel_config.reference = NRF_SAADC_REFERENCE_INTERNAL;                              //Set internal reference of fixed 0.6 volts
    channel_config.gain = NRF_SAADC_GAIN1_6;                                              //Set input gain to 1/6. The maximum SAADC input voltage is then 0.6V/(1/6)=3.6V. The single ended input range is then 0V-3.6V
    channel_config.acq_time = NRF_SAADC_ACQTIME_10US;                                     //Set acquisition time. Set low acquisition time to enable maximum sampling frequency of 200kHz. Set high acquisition time to allow maximum source resistance up to 800 kohm, see the SAADC electrical specification in the PS. 
    channel_config.mode = NRF_SAADC_MODE_SINGLE_ENDED;                                    //Set SAADC as single ended. This means it will only have the positive pin as input, and the negative pin is shorted to ground (0V) internally.
    channel_config.pin_p = NRF_SAADC_INPUT_AIN7;                                          //Select the input pin for the channel. AIN7 pin maps to physical pin P0.31.
    channel_config.pin_n = NRF_SAADC_INPUT_DISABLED;                                      //Since the SAADC is single ended, the negative pin is disabled. The negative pin is shorted to ground internally.
    channel_config.resistor_p = NRF_SAADC_RESISTOR_DISABLED;                              //Disable pullup resistor on the input pin
    channel_config.resistor_n = NRF_SAADC_RESISTOR_DISABLED;                              //Disable pulldown resistor on the input pin

	
    //Initialize SAADC channel
    err_code = nrf_drv_saadc_channel_init(7, &channel_config);                            //Initialize SAADC channel 7 with the channel configuration
    APP_ERROR_CHECK(err_code);
		
    if(SAADC_BURST_MODE)
    {
        NRF_SAADC->CH[7].CONFIG |= 0x01000000;                                            //Configure burst mode for channel 7. Burst is useful together with oversampling. When triggering the SAMPLE task in burst mode, the SAADC will sample "Oversample" number of times as fast as it can and then output a single averaged value to the RAM buffer. If burst mode is not enabled, the SAMPLE task needs to be triggered "Oversample" number of times to output a single averaged value to the RAM buffer.		
    }

    err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0],SAADC_SAMPLES_IN_BUFFER);    //Set SAADC buffer 1. The SAADC will start to write to this buffer
    APP_ERROR_CHECK(err_code);

    
    err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1],SAADC_SAMPLES_IN_BUFFER);    //Set SAADC buffer 2. The SAADC will write to this buffer when buffer 1 is full. This will give the applicaiton time to process data in buffer 1.
    APP_ERROR_CHECK(err_code);


}