Link loss Proximity with Android App

[Dragon Lai]

Hi All,

We are develop a BLE device which using Proximity profile. And we are modifying the nRF-Toolbox android apk to implement our application. We would like to change the response time of  link loss event on APK when we power off the ble device. Is it related to the  max GATT conn time in the ble device? or should we change the connection timeout in android side?

best regards,

Dragon

[Hung Bui]

Hi Dragon, 

It's related to the connection timeout. So we notify the the phone when the connection to the device is terminated. If you shorten the connection timeout you can get quicker response when the device power off. 

[Dragon Lai]

Did you mean that there is a parameter for connection timeout. I can not find the related parameter on source code of android . is it assigned on the ble device code ? I found 3 parameters on ble code such as CONN_SUP_TIMEOUT, MIN_CONN_TNTEVAL, MAX_CONN_INTERVAL.

[Hung Bui]

It's the CONN_SUP_TIMEOUT. But it's not guaranteed that the phone would accept any value from that. It's up to the OS to accept that or not, not the mobile app. 

[Dragon Lai]

Hi Bung Bui,

Any method we get faster response if there is link loss? between android/ios and 52832/42840 device?

Best Regards,

Dragon

[Hung Bui]

Hi Dragon,

Have you tried to request shorter CONN_SUP_TIMEOUT ? Could you capture a sniffer trace of the connection so we know what exact connection supervision timeout was used on the connection. 

If the connection timeout can't be reduced what you can think of is to use a notification or a read command to continuously read/notify and if the phone don't see a notification or can't do a read command it can trigger an alarm.