Mitsubishi Electronics UD740U Control command configuration, Control sequence, Ack/Nak, Ascii

2. Control command configuration

The command consists of the address code, function code, data code, ACK/NAK, and end code. The length of the command varies among the functions.

	Address code		Function code		Data code	ACK/NAK	End code
ASCII		‘30h’ ‘30h’		Function	Data	‘3Ah’ ‘4Eh’	‘0Dh’
Character		00		Function	Data	:N
[Address code]		Fixed to 00. (‘30h’ ‘30h’ in the ASCII code)
[Function code]		Code unique to each control operation.
[Data code]		Data (value) unique to each control operation (Not always indicated.)
[ACK/NAK]		Code indicating the NAK return as described below
		Fixed to :N (‘3Ah’ ‘3Eh’ in the ASCII code. Not added to ACK.)
[End code]		Fixed to		. (‘0Dh’ in the ASCII code)

3. Control sequence

Computer Projector

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	Sequence	Note
1	Send the command from the personal
	computer to the projector.
	The projector will send a return	If the projector does not receive commands
	command after it receives an end code.	normally, that is, if the projector is not connected
		physically or unable to receive commands, it does
2		not send out a return command.
		The projector sends out a return command within
		one second at the latest.
		When the received command cannot be executed,
		NAK is returned (as described below).
	The personal computer checks the
3	command and confirms if the sent
	command has been received or not.
	Use the check command to see if the	This projector sends various codes other than the
4	projector has executed the command.	return code. When having a control sequence by
		RS-232C, reject other codes from the personal
		computer.

∙NAK return

In the following cases, the projector returns the command with “:N” added.

(1)Though the command sent from the computer is received by the projector successfully, it cannot be executed because the projector is in the operation prohibition state.

(2)The data length of the sent command is incorrect or the command is invalid.

∙When a command is sent out during the following operations, it may not be executed.

(1)During signal switching

(2)In the process of the auto position

(3)After the power is turned on.

The projector receives no commands for about 20 seconds (or for 2 minutes at the longest if the lamp does not light up promptly as the life is expiring). In this case, the projector returns the received command with NAK added.

∙The return command is sent out within 1 second at the latest.

∙When sending commands successively, wait to receive the return command of the current command before sending a next command.

∙The projector may not receive a command when the splash screen is being displayed immediately after turning on the power. Use command “00r10” to cancel the splash screen.

∙While using the LAN terminals, the LAN functions take precedence.

∙For the LAN terminals, the same commands as those for connecting with the TCP/IP (port number 63007) are available. Note, however, that the response becomes slightly slower than when using the RS-232C terminals. For the use of LAN terminals, see page 10.

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