remote wake up

RE: remote wake up

Karl Ylvisaker — Fri, 08 May 2020 12:09:55 GMT

[quote user="Kosar"]Thank you for your reply Karl.[/quote]

No problem at all, I am happy to help!
Though I would have to share credit with @Awneil in this case - he has been much swifter on the reply than me! 🙂

[quote user="Kosar"]I see in several discussions in devzone that some are suggesting using single shot timer. I need to get periodic advertisement. for example advertise in some minute and then stop for some other minute and so on...[/quote]

For this, you could use the app timer module in repeated mode(not single shot) to have it trigger advertising periodically. App timer usage is demonstrated in many of the examples, for example the Proximity example where it is used to periodically measure battery voltage.
Alternatively, depending on your application, NFC might also be an option for wakeup, as Awneil suggested.

Best regards,
Karl

RE: remote wake up

awneil — Thu, 07 May 2020 13:31:16 GMT

[quote userid="79996" url="~/f/nordic-q-a/61126/remote-wake-up/248729"]I do not want to use any physical pin[/quote]

But does NFC (or similar) remain an option?

[quote userid="79996" url="~/f/nordic-q-a/61126/remote-wake-up/248729"]advertise in some minute and then stop for some other minute and so on[/quote]

Sure, you can do that.

RE: remote wake up

karoun — Thu, 07 May 2020 13:26:49 GMT

Thank you for your reply Karl.

Since the intention is to have an implantable device I do not want to use any physical pin. I see in several discussions in devzone that some are suggesting using single shot timer. I need to get periodic advertisement. for example advertise in some minute and then stop for some other minute and so on...

RE: remote wake up

Karl Ylvisaker — Thu, 07 May 2020 12:59:55 GMT

Hello Kosar,

As awneil said, the central(phone) will not know about the peripherals presence if it is not advertising, but there are many other ways to have the peripheral wake up at different intervals or events.
The chosen wakeup method and advertising parameters will significantly impact the power consumption, but it is also not possible for us to suggest anything in particular without knowing more about the intended application.

If you are looking to go the route of a GPIO wakeup signal, you might be interested in seeing the Pin Change Interrupt example, which demonstrates how to set up an interrupt on pin change. You may also want to have a look at the BLE Blinky app for seeing the basic BLE parts of peripheral implementation.

Best regards,
Karl

RE: remote wake up

awneil — Thu, 07 May 2020 08:46:58 GMT

The Central (eg, phone) cannot see the Peripheral unless it is advertising - so there is no way to do this using BLE alone.

[quote userid="79996" url="~/f/nordic-q-a/61126/remote-wake-up"]Low power consumption is an important consideration[/quote]

How "low", exactly?

Even when advertising, the time that the radio is actually active is only a small fraction of the total time.

Could you use another wakeup signal; eg, NFC, a tap. etc ?

Choose your advertising parameters carefully - it's a tradeoff between how quickly & reliably the Central can find the device, and how much power you use.