RS-232C COMMUNICATION (continued)

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 a command sent by the projector cannot be understood by the computer

When the command sent by the projector cannot be understood, the error command ‘15H’ is returned by the computer. Some times, the projector ignores RS-232C commands during other works. If the error command ‘15H’ is returned, please send the same command again.

When data sent by the projector cannot be practice

When the command sent by the projector cannot be practiced, the the error code ‘1cH’ +‘xxxxH’ is returned.

When the data length is greater than indicated by the data length code, the projector will 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 projector.

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.

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Hitachi EDX-3270A, EDS3170A user manual Requesting projector status Get command, Changing the projector settings Set command