nRF52832, TWI and low power

[PW]

Hello. I've got issue with TWI and power down mode. I modificated "ble_app_bps" example, prepared own service and characteristic and I added BME280 sensor. And almost everything works fine. Almost.... After read sensor via TWI (perdiodically, one time on 5 sec), nrf52832 doesn't go to sleep. PCA100040 takes high constant current (about 6mA) + tx peaks (measure by PCA63511). NRF_LOG is disabled. Please help, I can't find my mistake :/

Main loop:

while(1)
{
    if (NRF_LOG_PROCESS() == false)
    {
		power_manage();
    }
		
}

Timer handler:

static void sensor_timeout_handler(void * p_context)
{
	UNUSED_PARAMETER(p_context);

	twi_config();

	t = bme280_read_temp();
	p = bme280_read_pressure();
	h = bme280_read_humidity();

	nrf_drv_twi_disable(&m_twi_master);
	
	nrf_drv_twi_uninit(&m_twi_master);
	
	*(volatile uint32_t *)0x40003FFC = 0;
	*(volatile uint32_t *)0x40003FFC;
	*(volatile uint32_t *)0x40003FFC = 1;

}

[MartinBL]

Hi,

Are you using floating point variables? Watch out for this errata: [87] CPU: Unexpected wake from System ON Idle when using FPU. 6mA sounds like the CPU is running and refuses to go to sleep and erratum 87 leaves the CPU running forever if you use floats in your code. 

[PW]

Of cource you have right :). I searched in TWI functions and I forgot about float. Thanks.