Nordic Thingy 52 - external I2C sensor device driver implementation

Question

Hello everyone, 
 
 i'm trying to hook up an external i2C sensor to P5 connector (TWI_SCL_EXT, TWI_SDA_EXT) and created a device driver template ( from drv_gas_sensor.c example) . 
 to start with i have created this function in m_environment.c: 
 /**@brief Function for initializing the MY sensor */ static uint32_t my_sensor_init(const nrf_drv_twi_t * p_twi_instance) { uint32_t err_code; drv_my_init_t init_params; static const nrf_drv_twi_config_t twi_config = { .scl = TWI_SCL_EXT, .sda = TWI_SDA_EXT, .frequency = NRF_TWI_FREQ_400K, .interrupt_priority = APP_IRQ_PRIORITY_LOW }; init_params.p_twi_instance = p_twi_instance; init_params.p_twi_cfg = &twi_config; init_params.twi_addr = MY_ADDR; init_params.data_handler = drv_my_data_handler; err_code = drv_my_init(&init_params); RETURN_IF_ERROR(err_code); return NRF_SUCCESS; } 
 
 //and calling this function in m_environment_init() function as below 
 err_code = my_sensor_init(p_params->p_twi_instance); APP_ERROR_CHECK(err_code); 
 
 let me know if this is right.

Simon · Accepted Answer

Why are you starting and stopping the timer? Isn't it possible to create a repeated timer that fires every 1 second? 
 I have not tested this myself, and I am not sure if this is the best way to go about it, but here I will present an approach that might work 
 In drv_mysensor.c 
 
 Create an enable function ( similar to drv_humidity_enable(..) where you create and start a repeated timer that triggers idle_timer_evt_scheduler() 
 Inside idle_timer_evt_scheduler() run app_sched_event_put(NULL, NULL, reset_idle_timer_event) 
 In the function reset_idle_timer_event() only run m_drv_pm.evt_handler(DRV_MYSENSOR_EVT_DATA); 
 Create in init function (similar to drv_humidity_init(..) )
 
 Here you can create the repeated timer (not start it) 
 In addition you set your event handler m_drv_pm.evt_handler here

In m_environment.c 
 
 Create the event handler (similar to humidity_timeout_handler() ) 
 Run the init and enable function that you created in drv_mysensor.c 
 
 Best regards, 
 Simon

Nordic Thingy 52 - external I2C sensor device driver implementation

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