Why does the gpio pin not retain the previously set state when the system is in shutdown mode (PM_STATE_SOFT_OFF)?

[Dinh Son]

Hi!

Specifically when I set pinLdo low before entering system shutdown mode, but in fact pinLdo pulled up after entering that mode. When the chip has not entered the system shutdown state (PM_STATE_SOFT_OFF), I can still set the high or low level of that gpio.

Is there a way to keep gpio's state when the system shuts down without changing gpio state?

[Øyvind]

Hello, 

Could you please provide more details on what you are trying to achieve? With what application are you testing? 

Kind regards,
Øyvind

[Dinh Son]

Hi! 

I am using the nrf5340 raytak board with zephyr sdk, I put the board into system off state and gpio Ldo at low level before entering that state, but when entering system off state, gpio Ldo has been brought to high level. It seems that it cannot maintain the state it was set before the system shutdown. Do you have any way I can keep gpio state while system is off until it is rebooted

Besides, I tried using the vom clock to measure the logic level of the gpio Ldo. After the system turned off, it was pulled at a high level.

The purpose is to save energy 

[Øyvind]

Dinh Son said:

I am using the nrf5340 raytak board with zephyr sdk

So you are not using the nRF Connect SDK? If you are using NCS, what version are you running? I'm not familiar with this board and will need to investigate more. 

Dinh Son said:

Do you have any way I can keep gpio state while system is off until it is rebooted

This should be retained by device itself. Please note that in our latest version of NCS, we have introduced Power Off

Kind regards,
Øyvind