HP LD4235 41.92-inch LED Digital Signage Display - Manual (Page 111)

[j][o][ ][Set ID][ ][Data][Cr]
Data
00 to FE: Blue Gain 0 to 254
Acknowledgement
[o][ ][Set ID][ ][OK/NG][Data][x]
56. Backlight (Command: m g)
To adjust the screen backlight.
Transmission
[m][g][ ][Set ID][ ][Data][Cr]
Data
00 to 64: Backlight 0 to 100
Acknowledgement
[g][][set ID][][OK/NG][Data][x]
** It may not be supported depending on the model.
Transmission / Receiving protocol 101