Hitachi CP-X809W User Manual page 217

RS-232C Communication (continued)
Requesting projector status (Get command)
Changing the projector settings (Set command)
Using the projector default settings (Reset Command)
Increasing the projector setting value (Increment command)
Decreasing the projector setting value (Decrement command)
When the projector cannot understand the received command
When the projector cannot execute the received command.
NOTE
8