Low power modes management

RE: Low power modes management

Menon — Tue, 13 May 2025 06:23:01 GMT

Hello,

Please create a new ticket for your issue, as this one is quite old.

Kind regards,
Abhijith

RE: Low power modes management

salmanMaLiKk — Mon, 12 May 2025 14:48:20 GMT

Hello Guys,

Its been a while since you worked on this but i am working on a similar project with a Lis3dh sensor.

But i also add the SMp zerver into the code and it cause issues for the low power any idea what could be causing that?

Salman

RE: Low power modes management

Menon — Fri, 03 Jun 2022 14:00:18 GMT

Hello,

Sorry for the delayed response. I think you got mixed up with periodic advertising and extended advertising, where periodic advertisement is a type of extended advertising which is not connectable, just advertising but in case of extended advertising it is connectable and scannable.

If your end goal is to configure the advertising period make use of the function bt_le_adv_param() and edit the parameters.

Kind Regards,

Abhijith

RE: Low power modes management

V.Lorz — Thu, 19 May 2022 16:41:27 GMT

Hello, Menon,

I've been playing with referenced sample code (periodic_adv), but I don't think it's what I'm looking for, at least not exactly, yet it has been useful for understanding a bit more about this ecosystem.

AFAIK, extended advertisements are not connectable and, indeed, if I specify option BT_LE_ADV_OPT_CONNECTABLE, bt_le_per_adv_set_param() fails with error code EINVAL. My device is required to allow connections.

RE: Low power modes management

Menon — Thu, 19 May 2022 12:56:29 GMT

Hello,

For configuring the advertising period you can actually make use of the periodic advertising function where you can set the parameters in the function bt_le_ext_adv_set_param(). You can refer the sample program in Connect SDK folder ncs\v1.9.1\zephyr\samples\bluetooth\periodic_adv.

And for shutting down the advertising bt_le_adv_stop() works.

Please see our optimizing power on nRf52 page.

Kind Regards,

Abhijith

RE: Low power modes management

V.Lorz — Wed, 18 May 2022 07:02:46 GMT

I'll share some results, for just in case they're useful for anyone else.

There's nothing to do for entering low power, system on, in zephyr. Only thing is to put all threads to sleep and zephyr will do the rest. Trying to enter low power using the combination { __WFE(); __SEV(); __WFE(); } will not work as the CPU will be constantly taken out of low power by events which are controlled by zephyr.

For going to low power, wake-up periodically, then go to low power again, a simple loop in main() does the trick.

    while (true)
	{
		k_sleep(K_SECONDS(1));

		// Do some stuff every one second
		// ... 
	}

Here is a current consumption frame captured with a PPK-II corresponding to the moment an advertisement is sent. Average current seems to be large, but it is due to averaging only 17ms. It goes down to 23.7uA when averaging for a 2min period.

This far, my question "How do I do for properly entering System On low power mode?" is solved, by I still have others.

In the call to bt_le_adv_start(), I specify params as: BT_LE_ADV_PARAM(BT_LE_ADV_OPT_CONNECTABLE, BT_GAP_ADV_SLOW_INT_MIN, BT_GAP_ADV_SLOW_INT_MAX, NULL).

How do I configure for advertising periods longer than 1 second?

How do I do for properly shutting down advertising and updating the advertisement data?

Thanks in advance.