nRF52-DK automatic reconnect to android with Nordic nRF Connect App

[NAM_HongJae]

Hi,

   I'm using nRF52-DK evaluation board, and ble_app_template_pca10040_s132 (from examples of nRF5_SDK_17.00.9d13099)

I'm designing an android smartphone as a central,  nRF52-DK EV board as a peripheral

,and using "nRF Connect for Mobile" App form Nordic to connect the EV board. 

  What I want to do is that

if terminate nRF App and turn it back on, my EV board will automatically reconnect. 

  nRF Connect App already support a function "Connect with autoConnect", but

this autoConnect is executed when EV board turns off & on again.

 if I terminate nRF App, I should touch "connect" button to confirm reconnection.

  Is there any way to operate auto-reconnection between nRF52 & android without external confirm 

, like commercial Bluetooth earphones ?

Thanks,

[Karl Ylvisaker]

Hello,

What awneil is saying is correct - it is the central that will need to initiate the connection by sending a connection request to the peripheral.
If you are making your own Android application, or using the nRF Connect application then you may have these use AutoConnect to automatically reconnect with your device when they receive an advertisement from it.

In your original ticket I see that you specifically mention the ability to automatically reconnect without running a particular application and without having to confirm the reconnection ( if I have understood you correctly ), like the user-experience with headphones, for example.
To my knowledge, the Android OS only does this for devices with the GATT HOGP profile - you can read more about this as part of the "link loss reconnection" section of the HOGP specification.

It is here important to beware of the difference between the "Bluetooth classic" profiles, and the GATT profiles used for Bluetooth Low-Energy, as @awneil also mentions.

Please do not hesitate to ask if you should encounter any issues or questions!

Best regards,
Karl