Why I I got "NRF_DRV_TWI_EVT_DATA_NACK" when try to call "nrf_drv_twi_tx" in another function??

[sosse]

In the main function, this works.

Works ..

err_code = app_timer_start(my_led_timer_id, APP_TIMER_TICKS(4500, APP_TIMER_PRESCALER), NULL);
APP_ERROR_CHECK(err_code); 

err_code = nrf_drv_twi_tx(&m_twi_sht_30, SHT_ADDRESS, reg, sizeof(reg), false);
APP_ERROR_CHECK(err_code);
m_xfer_done = false; 



for (;;)
{
app_sched_execute();
power_manage();
}

Not works, I got NRF_DRV_TWI_EVT_DATA_NACK error..

err_code = app_timer_start(my_led_timer_id, APP_TIMER_TICKS(4500, APP_TIMER_PRESCALER), NULL);
APP_ERROR_CHECK(err_code); 

sht_measurement();


for (;;)
{
app_sched_execute();
power_manage();
}

static void sht_measurement(void){
		 uint32_t err_code;
		 uint8_t reg[2] = {0x2c, 0x06};

		 err_code = nrf_drv_twi_tx(&m_twi_sht_30, SHT_ADDRESS, reg, sizeof(reg), false);
		 APP_ERROR_CHECK(err_code);
		 m_xfer_done = false;							
}

and I cannot call "nrf_drv_twi_tx" in the timer event handler function? When I try to call "nrf_drv_twi_tx" in the timer event handler (for requesting data from SHTx sensor),

I got same error, NRF_DRV_TWI_EVT_DATA_NACK . 

[MartinBL]

That is strange.

Is sht_measurement() defined in the same file? I assume SHT_ADDRESS and the reg buffer is containing the exact same address and buffer?

[sosse]

yes, the sht_measurement() is defined in the same file.  

[MartinBL]

Can you upload the rest of your code?