4.2.5.1.2 Immediate Alert Service
This service exposes a control point to allow a peer device to cause the device to alert immediately.
The proximity monitor will calculate the path loss:
Path Loss = Tx Power Level – RSSI
If the path loss exceeds a certain threshold, the monitor may write the Alert Level characteristic of the IAS, thereby prompting the user to perform appropriate action to avoid disconnection.
The Alert Level characteristic can be written using the GATT Write Without Response sub-procedure with an alert level of “No Alert,” “Mild Alert,” “High Alert,” to set the written alert level.
|
Characteristic |
Mandatory/Optional |
Characteristics Property |
|---|---|---|
Alert Level | Mandatory | Write, Without Response |
When the Alert Level characteristic is written the device shall start alerting to the written alert level.
If the written alert level is “No Alert,” no alerting shall be done on this device.
If the written alert level is “Mild Alert,” the device shall alert.
If the written alert level is “High Alert,” the device shall alert in the strongest possible way.
The specific action that occurs in the device for the mild and high alerts is implementation specific. For example, this could include flashing lights, making noises, moving, or other methods to alert the user.