Hitachi CP-S245 User Manual page 100

Requesting projector status (Get command)
(1) Send the request code Header + Command data ('02H'+'00H'+ type (2 bytes)+
'00H' +'00H') from the computer to the projector.
(2) The projector returns the response code '1DH'+ data (2 bytes) to the computer.
Changing the projector settings (Set command)
(1) Send the setting code Header + Command data ('01H'+'00H'+ type (2 bytes) +
setting code (2 bytes)) from the computer to the projector.
(2) The projector changes the setting based on the above setting code.
(3) The projector returns the response code '06H' to the computer.
Using the projector default settings (Reset Command)
(1) The computer sends the default setting code Header + Command data ('06H'+
'00H' + type (2 bytes) +'00H'+'00H') to the projector.
(2) The projector changes the specified setting to the default value.
(3) The projector returns the response code '06H' to the computer.
Increasing the projector setting value (Increment command)
(1) The computer sends the increment code Header + Command data ('04H'+
'00H'+ type (2 bytes) +'00H'+'00H') to the projector.
(2) The projector in creases the setting value on the above setting code.
(3) The projector returns the response code '06H' to the computer.
Decreasing the projector setting value (Decrement command)
(1) The computer sends the decrement code Header + Command data ('05H'+
'00H'+ type (2 bytes) +'00H' + '00H') to the projector.
(2) The projector decreases the setting value on the above setting code.
(3) The projector returns the response code '06H' to the computer.
When the projector cannot understand the received command
When the projector cannot understand the received command, the error code '15H'
is sent back to the computer.
Sometimes the projector cannot properly receive the command. In such a
case, the command is not executed and the error code '15H' is sent back to the
computer. If this error code is returned, send the same command again.
When the projector cannot execute the received command.
When the projector cannot execute the received command, the error code '1cH'
+ 'xxxxH' is sent back to the computer. When the data length is greater than
indicated by the data length code, the projector ignore the excess data code.
Conversely when the data length is shorter than indicated by the data length
code, an error code will be returned to the computer.
NOTE • Operation cannot be guaranteed when the projector receives an undefined
command or data.
• Provide an interval of at least 40ms between the response code and any other code.
• The projector outputs test data when the power supply is switched ON, and when the
lamp is lit. Ignore this data.
• Commands are not accepted during warm-up.
RS-232C Communication (continued)
7