NUS shut down & restart

RE: NUS shut down & restart

Priyanka — Wed, 22 Oct 2025 11:46:58 GMT

Hi John,

Apologies for the delayed response.

[quote user="John Galvin"] get round this by waiting for the wrong button to be released before going back to sleep. This fixed my problem.[/quote]

This sounds like a good solution and sounds fine.

-Priyanka

RE: NUS shut down & restart

John Galvin — Tue, 07 Oct 2025 08:31:39 GMT

I was able to use the restart option by chaning my software to allow a restart to test the buttons. How I get excellent power off current (~300nA)

One note. If I press the wrong button to wake it up, then realse this & press the correct button, it doesn't wake. I'm guessing I needed to clear the IRQ before going back to sleep after the wrong button press. Howver, I get round this by waiting for the wrong button to be released before going back to sleep. This fixed my problem.

Can you see any reason why this may not be a suitable solution?

RE: NUS shut down & restart

Priyanka — Tue, 02 Sep 2025 13:41:43 GMT

Hi John,

[quote user="John Galvin"]

It seams to reset my code & run from the begining?

Is that correct?

[/quote]

Yes you can see here https://docs.nordicsemi.com/bundle/ps_nrf5340/page/chapters/reset/doc/reset.html that the device resets when waking up from System OFF, so then it starts from the main().

[quote user="John Galvin"]does "sense-edge-mask = <0x01800000>; /* 1<<24 | 1 <<23 */" solve this issue?[/quote]

The higher idle current come from using GPIOTE IN channels for GPIO interrupts. Switching those pins to use the GPIO SENSE/PORT event path usually fixes it. That’s exactly what the sense-edge-mask devicetree property does.

-Priyanka

RE: NUS shut down & restart

John Galvin — Wed, 20 Aug 2025 11:54:35 GMT

Hi Priyanka,

I've now finally got back on to this. I'm using the dk_buttons library

gpio_pin_set_dt(&j3pins[2], 1); //### test probe: set high when enter poweroff
sys_poweroff();
gpio_pin_set_dt(&j3pins[2], 0); //### test probe: set low when exit poweroff

Monitoring my test probe pin it goes high as expected when entering sys_poweroff() & when I press my button my test probe goes low as expected, but it doesn't carry on running from where it left off. I then put a break point at the system start which it hit. It seams to reset my code & run from the begining?

Is that correct?

Also I noticed your comment in the other ticket saying that dk_buttons_and_leds.c library you see a higher IDLE current.

does "sense-edge-mask = <0x01800000>; /* 1<<24 | 1 <<23 */" solve this issue? If so, are this bits related for their GPIO pins (23 & 24)?

RE: NUS shut down & restart

Priyanka — Mon, 04 Aug 2025 12:57:15 GMT

Hi John,

You could use the sys_poweroff() API for the same.

First configure the button GPIO as input and set the sense mechanism (so it can wake the device from System OFF). Then call sys_poweroff() to enter System OFF mode.

This ticket could help you get a idea.

-Priyanka