NEC NDA-30115-001 manual Syn, Stx, Etx, ACK0, ACK1 NAK, Wack, Ttd, Rvi, Pad-L, Pad-T

Architecture Property Management System - Communication Interface

The control codes used for the message texts are:

		Table 2-6 Control Codes
Control Code	Hexadecimal	Function
	Value
SYN	32	Synchronization code.
STX	02	Indicates the start of a block.
ETX	03	Indicates the end of a block.
ENQ	2D	Used as the start sequence code. It indicates a reception
		request to the other side and a request to answer an infor-
		mation block just sent.
EOT	04	Indicates the end of transmission of a block or release of
		the data link by the sender.
ACK0	10, 70	Used alternately, these indicate the positive acknowledg-
		ment of an information block or a start sequence.
ACK1	10, 61
NAK	3D	Indicates the negative acknowledgment of an informa-
		tion block or a start sequence.
WACK	10, 6B	Used as the positive acknowledgment of an information
		block or start sequence and indicates that the receiver
		temporarily cannot receive data from the sender.
TTD	02, 2D	Indicates that the sender cannot transmit the next infor-
		mation block after the receipt of the answer to the previ-
		ous information block sent from the receiver.
RVI	10, 7C	Indicates the positive acknowledgment of an information
		block and asks the sender for sending rights.
PAD-L	55	Indicates the absolute beginning of the entire informa-
		tion block.
PAD-T	FF	Indicates the absolute ending of the entire information
		block.

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