Dim all dimmer devices on a segment to a specified dim value. 

 | Data byte | Description                                                                             | 
 | :---------: | -----------                                                                             | 
 | 0         | Value (0 – 100) . 0 = off, 100 = full on. 254 dim down one step. 255 dim up one step. | 
 | 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.                      | 
