Hi,
In my proejct, I am using WFE(); in some while loops because of core low power mode.
For example, waiting for time_out flags like codes below.
I am wondering if it is helpful to use WFE(); in terms of power consumption and if the example usage is proper.
Also, the other question is do I need to set up anything (interrupt pin or timer) to wake device up from the WFE low power mode state? or just call WFE(); anywhere if I use while loop?
int i2c_read(i2c_s *obj, uint8_t devAddr, uint8_t *data, uint8_t length)
{
i2c_xfer_done[obj->instance] = false;
int retry = I2C_RETRY_NUM;
ret_code_t err_code = nrf_drv_twi_rx(obj->i2c_dev, devAddr, data, length);
if (err_code != NRFX_SUCCESS)
{
debug_verbose(NON_CRITICAL_ERROR, SENSOR_CONTROL_CATEGORY, "i2c_read: nrf_drv_twi_init error\r\n");
}
while (i2c_xfer_done[obj->instance] == false && retry--)
{
#ifdef SOFTDEVICE_PRESENT
if(nrf_sdh_is_enabled())
{
sd_app_evt_wait();
}
else
#endif // SOFTDEVICE_PRESENT
{
__WFE();
}
}
if (retry < 0)
{
err_code = NRFX_ERROR_TIMEOUT;
}
return err_code;
}
while(get_interruptPin_level_C() == 0 && !timed_out) // TODO: app timer expired immediately
// while(get_interruptPin_level_C() == 0 && (timeOutTicks > os_getTime() - startTick))
{
#ifdef SOFTDEVICE_PRESENT
if(nrf_sdh_is_enabled())
{
sd_app_evt_wait();
}
else
#endif // SOFTDEVICE_PRESENT
{
__WFE();
}
}
Thanks!
