void vSPO2Meas(void const * argument)
{
    uint16_t i=0;
  for(;;)
  {
      for(i=0;i<n_ir_buffer_length;i++)
          {
              while(HAL_GPIO_ReadPin(MAX30102_INT_GPIO_Port, MAX30102_INT_Pin)==1);   //wait until the interrupt pin asserts

              maxim_max30102_read_fifo(hi2c1, (aun_red_buffer+i), (aun_ir_buffer+i));  //read from MAX30102 FIFO

              if(un_min>aun_red_buffer[i])
                  un_min=aun_red_buffer[i];    //update signal min
              if(un_max<aun_red_buffer[i])
                  un_max=aun_red_buffer[i];    //update signal max
          }
          un_prev_data=aun_red_buffer[i];
          //calculate heart rate and SpO2 after 500 samples
          saturation=maxim_heart_rate_and_oxygen_saturation(aun_ir_buffer, n_ir_buffer_length, aun_red_buffer, &n_sp02, &ch_spo2_valid, &n_heart_rate, &ch_hr_valid);
          //sp02toUART(huart3, n_sp02, ch_spo2_valid);

          osDelay(10000);
  }
}