system OFF

[tvjz]

We are experiencing some mysterious but very rare events of MCU going into system OFF mode. We are using nRF51822 and S110 v7.3.0. The wake ups are most likely caused by a software bug, but still:

I'd like to know if there is a way to get the MCU to the system OFF state with some other way than calling sd_power_system_off();?

Are there some error states where the MCU would go to system OFF?

Could it happen if the debug wires float?

Or by ESD peak perhaps?

[edit: cleared the question]

[Susheel Nuguru]

That is right, there is no other way. I think there is a memory corruption in your system which is writing to this specific register. If should be easy to set a write access breakpoint and see when it is triggered.(in Keil i know its possible, do not know how you do it in other debuggers)

[Bluesky]

Hi, I would like to ask how can i get the current consumption that was stated in the datasheet which is 0.7uA and the value I get from the reading is about 8-9 uA.

My code is just simple as below,

#include "boards.h"

/**
* @brief Function for application main entry.
*/
int main(void)
{
NRF_POWER->SYSTEMOFF = 1;
}
/** @} */

[Susheel Nuguru]

Please open a new case mentioning which chip version you tested this with and SDK version too.

There are some errata workarounds in the startup files, that might effect your readings, but before we investigate that, please open new case giving us more details on the setup.