Protocol; Header; Command Data - Hitachi CP-WX625 - WXGA LCD Projector Technical Manual

Decreasing the projector setting value (Decrement command)
(1) The PC sends the following decrement code to the projector.
Header + Command data ('05H' + '00H' + type (2 bytes) + '00H' + '00H')
(2) The projector decreases the setting value on the above setting code.
(3) The projector returns the response code '06H' to the PC.
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 PC.
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 PC. 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 PC.
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 PC.
When authentication error occurred.
When authentication error occurred, the error code the '1FH' + '0400H' is sent
back to the PC.
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.
• Commands are not accepted during warm-up.
[TCP #9715]

1. Protocol

Consist of header (1 byte) + data length (1 byte) + command data (13 bytes) +
check sum (1 bytes) + connection ID (1 byte).

2. Header

02, Fixed
3. Data Length
Network control commands byte length (0D, Fixed)

4. Command data

Network control commands that start with BE EF (13bytes).
5. Check Sum
This is the value to make zero on the addition of the lower 8 bits from the header
to the checksum.
6. Connection ID
Random value from 0 to 255 (This value is attached to the reply data).
CPWX625(ED3WX40N)
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