nRF52840 Demo Sleep Mode

[adragocelestica]

Hi,

I have followed the steps for the 2 demos for nRF52840 DK, the Heart Rate and the Proximity demo. In both cases, when disconnected from the android device, the evaluation board should enter in sleep mode when pressing button 1 or after 3 minutes, according to the readme.txt file in the demo. That is not happening in my board, and I cannot figure out why.

I have waited the 3 minutes, and it hasn't gone into sleep mode, and when pressing button 1 the LED1 lights up instantly for a moment, and then keeps blinking, it doesn't get turned OFF as it should be.

The only thing I can think of is that somehow the chip is always looking for BT devices or something like that, but the LED1 is blinking so it is in "advertising" mode, it should go to sleep mode.

Thanks in advance for your help.

[Bjørn Kvaale]

When you refer to the heart rate and proximity demos, you mean these two applications, right: app 1, app 2? I could not find any info regarding setting the device to sleep by pressing button 1. Are you using SDK 15? Normally, the device will turn off after advertising for 180 seconds to save power. When you press button 1 when the device is sleeping, it normally turns on & continues advertising for 180 seconds & then goes to sleep if no central Bluetooth device connects to it (I am assuming your device is the peripheral device in this instance). 

Basically: I believe the usage you mention is correct. The device will turn off after 180 seconds of advertising, button 1 turns advertising on again once the device is sleeping

[adragocelestica]

Oh, I almost forget. If i try to connect via Bluetooth from my Android device via the nRFTools app and Android has the nRF52840 as a BT linked device, the examples don't work properly and nRFTools disconnects me immediately. When I deleted the device from the BT linked devices, the examples started working again. You should really fix that, or at least write it down somewhere in the documentation, because it is quite frustrating at first to test a first example and not understanding why the connection is not working right.

[Bjørn Kvaale]

I'd say this is quite well documented in all of our sdk examples (see Testing section). Although it might seem intuitive to connect via the Bluetooth settings, it does not say in the testing examples section that you should connect your phone via the Bluetooth settings before using the nrf toolbox app.