Setting linkloss alertlevel on device through android application

[balaji]

Hi,

I am working on proximity android application, i implemented immediate alert service, which is working fine. Now i need to set the alert level on the tag for linkloss as same as in the iphone application. how can i do this. what is happening when i set the on tag alert level through iphone applicattion?

Regards, Balaji.

[Balaji Srinivasan]

Hi Balaji,

For Link Loss alerts, your Android application will need to discover 'Link Loss Service' on the tag and write to the 'Alert Level' characteristic which is included in it.

Hope this helps.

Cheers, Balaji

[balaji]

Thank for the reply balaji, What is happening in the iphone proximity application, when we set the on tag alert levels?

[Balaji Srinivasan]

The app will be writing 0x02' (High Alert) or 0x01 (Mild Alert) or 0x00 (No Alert) to the Alert Level characteristic in the Link Loss service as mentioned here -> https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.alert_level.xml

[balaji]

thanks balaji, what about the device side. i can see sd_ble_gatts_value_get(p_lls->alert_level_handles.value_handle, 0, &len, p_alert_level); which is called when the linkloss disconnection happens. But how the alert level value is received and settled in stack when we write through alertlevel characteristics?

[Balaji Srinivasan]

Not sure if I understand you correctly. But the alert level value is sent by the phone using GATT Write Request. This will be received received, stored and responded to by the BLE Stack running on the device. The value thus stored is read using the API sd_ble_gatts_value_get by the application on the device side (as you have mentioned). Is this clear?