Proximity detected.

 | Data byte | Description  | 
 | :---------: | -----------   | 
 | 0 | Optional byte that have a meaning given by the issuer of the event. | 
 | 1 | Zone for which event applies to (0-255). 255 is all zones. | 
 | 2 | Sub-zone for which event applies to (0-255). 255 is all sub-zones. | 
 | 3, 4 | Optional uint16 that sets proximity level if present. | 
 
