i configure the twi after 20 sec and keep it for 10 sec after that disable the twi.but after some time board is restting.

[Prathap Reddy]

if(sensor_en_time==read_time_interval)
{
	sensor_en_flag=true;
	data_store_flag=true;
}	

if((sensor_en_time)>read_time_interval)
{
	sensor_dis_time++; 	
}


if(sensor_en_flag)
{	
	nrf_gpio_cfg_output(13);
	nrf_delay_ms(5);
	nrf_gpio_pin_set(13);
	nrf_delay_ms(5);

	twi_config(); 
	nrf_delay_ms(5);
	sensor_en_flag=false;	
	uint8_t const mode_en_config[] = {0x06,0x0b};
	uint8_t const spo2_en_config[] = {0x07,0x00};//{ 0x07,0x00};//0x03 PULSE WIDTH  
	uint8_t const led_en_config[] =  {0x09,0xff};

	//initialize the max30100 pulse oximetre sensor
	nrf_drv_twi_tx(&m_twi,MAX30100_ADDRESS,mode_en_config,sizeof(mode_en_config),false);
	nrf_drv_twi_tx(&m_twi,MAX30100_ADDRESS,spo2_en_config,sizeof(spo2_en_config),false);
	nrf_drv_twi_tx(&m_twi,MAX30100_ADDRESS,led_en_config,sizeof(led_en_config),false);
}	
//		
if(sensor_dis_time>TIMER_10_SEC)
{
	sensor_dis_flag=true; 
	sensor_en_time=0;
	sensor_dis_time=0;
}

if(sensor_dis_flag)
{
	sensor_dis_flag=false;
	nrf_drv_twi_tx(&m_twi,MAX30100_ADDRESS,mode_dis_config,sizeof(mode_dis_config),false);
	twi_disable();
	nrf_delay_ms(5);
	data_store_flag=false;
	nrf_gpio_pin_clear(13);
	nrf_delay_ms(5);				
}

[MartinBL]

1. How are you initiating the TWI in twi_config()?

2. Are you using the TWI driver in blocking or non-blocking mode?

3. You seem to be using a lot of flags. Are these flags manipulated inside interrupt routines? If so, make sure to declare them using the 'volatile' keyword.

4. Please check the return codes of all your calls to nrf_drv_twi_tx() like this:

   err_code = nrf_drv_twi_tx();

   APP_ERROR_CHECK(err_code);

and then debug your code like this.