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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NDA-30115 Revision 1.0

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