I am still noticing a higher than expected power draw on my nRF52 and I want to make sure I have adopted best practice in turning things off/optimising things before entering sd_app_evt_wait(); It appears to be in the vicinity of 700 uAmps currently.
For this particular device I have a button which I am using with the app_button library in the v11 SDK. As far as I can see this is using GPIOTE port to sense the button which is best practice as I understand it.
I also have a TWI sensor which I power down after each reading by
uint32_t *twim0_power = (uint32_t *)(NRF_TWIM0_BASE+0xFFC);
*twim0_power = 0; //turn off TWIM0
*(volatile uint32_t *)twim0_power; //wait for register to be written (CPU runs faster than the peripherals)
*twim0_power = 1; //turn on TWIM0
nrf_drv_twi_disable(&m_twi_instance);
nrf_drv_twi_uninit(&m_twi_instance);
I have plenty of app_timers that I stop and start but these use the RTC and in any respect I have #define TIMER1_ENABLED 0 in my configurations so I don't think the nRF52 errata regarding the TIMER module should be a problem.
I don't use the UART (I used BLE NUS extensively) so I don't even init it in Main. However I still have #define UART0_ENABLED 1 in configurations.
I use SAADC to take a battery reading but I enable/disable this after each reading.
I do a floating point calculation so my power_manage() function looks like this
static void power_manage(void)
{
uint32_t err_code;
__set_FPSCR(__get_FPSCR() & ~(FPU_EXCEPTION_MASK));
(void) __get_FPSCR();
NVIC_ClearPendingIRQ(FPU_IRQn);
err_code = sd_app_evt_wait();
APP_ERROR_CHECK(err_code);
}
Is there anything else I ought to be doing before entering sd_app_evt_wait()?
