Remote controller lock/ key lock (command: k m), Key (command: m c) (not supported), Osd select (command: k l) – HP LD5535 55-inch LED Digital Signage Display User Manual
Page 99: Operating time (command: d l)

35. Remote Controller Lock/ Key Lock (Command: k m)
When the remote control and front keys are locked in standby mode, the power cannot be turned on using
the remote control or front power button.
Transmission
[k][m][ ][Set ID][ ][Data][Cr]
Data
00: Off (Lock Off)
01: On (Lock On)
* Display will not be turned on by power on key of remote controller and front panel control keys, if key is
locked on in standby mode.
Acknowledgement
[m][ ][Set ID][ ][OK/NG][Data][x]
36. Key (Command: m c) (not supported)
To send a key code of the IR remote control.
Transmission
[m][c][ ][Set ID][ ][Data][Cr]
Data
IR_KEY_CODE
Acknowledgement
[c][ ][Set ID][ ][OK/NG][Data][x]
For a key code, see the IR Code.
* Some key codes are not supported depending on the model.
37. OSD Select (Command: k l)
To select OSD (On Screen Display) on/off.
Transmission
[k][l][ ][Set ID][ ][Data][Cr]
Data
00: Off
01: On
Acknowledgement
[l][ ][Set ID][ ][OK/NG][Data][x]
38. Operating time (Command: d l)
To check the panel used time.
Transmission
Transmission / Receiving protocol
89