NEC NDA-30115-001 manual Neutral a ENQ D Waiting for NAK EOT a, sec EOT Waiting for EOT a

Architecture Property Management System - Communication Interface

Table 2-8 Data Transmission Sequence (2 of 2)

Status	EOT	TTD	WACK	(Timeouts)	(Transmis-
					sion Request)
Neutral (A)					ENQ -> (D)
Waiting for	-> (A)	d: NAK ->		EOT -> (A)
STX (B)		(B)		(25 sec)
		e: EOT ->
		(A)
Waiting for	-> (A)			EOT -> (A)
ETX, CRC				(25 sec)
(C)
Waiting for	-> (A)	d: ENQ ->	d: ENQ ->	f: ENQ ->
ACK after		(D)	(D)	(D)
start		e: EOT ->	e: EOT ->	g: EOT ->
sequence		(A)	(A)	(A)
(D)
Waiting for	-> (A)	d: ENQ ->	d: ENQ ->	f: ENQ ->
ACK after		(D)	(D)	(D)
message (E)		e: EOT ->	e: EOT ->	g: EOT ->
		(A)	(A)	(A)
				(3 sec)

Notes:

•a: Preparation for reception complete.

•b: Reception impossible.

•c: Requests for preparation for reception (the PMS should not request this).

•d: Transmitted up to 21 times.

•e: Aborted at 22nd time.

•f: Transmitted up to 7 times.

•g: Aborted on the 8th time.

•h: Message is received normally and preparation for next reception is complete.

•i: Error found in message.

•j: Interruption.

•k: Information to be transmitted is present.

•l: Information to be transmitted is absent.

•m: Retransmission of message.

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