NEC NDA-30115-001 User Manual
Page 16
NDA-30115 Revision 1.0
Architecture
Property Management System - Communication Interface
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.
Table 2-8 Data Transmission Sequence (2 of 2)
Status
EOT
TTD
WACK
(Timeouts)
(Transmis-
sion Request)
Neutral (A)
ENQ -> (D)
Waiting for
STX (B)
STX (B)
-> (A)
d: NAK ->
(B)
e: EOT ->
(A)
(B)
e: EOT ->
(A)
EOT -> (A)
(25 sec)
(25 sec)
Waiting for
ETX, CRC
(C)
ETX, CRC
(C)
-> (A)
EOT -> (A)
(25 sec)
(25 sec)
Waiting for
ACK after
start
sequence
(D)
ACK after
start
sequence
(D)
-> (A)
d: ENQ ->
(D)
e: EOT ->
(A)
(D)
e: EOT ->
(A)
d: ENQ ->
(D)
e: EOT ->
(A)
(D)
e: EOT ->
(A)
f: ENQ ->
(D)
g: EOT ->
(A)
(D)
g: EOT ->
(A)
Waiting for
ACK after
message (E)
ACK after
message (E)
-> (A)
d: ENQ ->
(D)
e: EOT ->
(A)
(D)
e: EOT ->
(A)
d: ENQ ->
(D)
e: EOT ->
(A)
(D)
e: EOT ->
(A)
f: ENQ ->
(D)
g: EOT ->
(A)
(3 sec)
(D)
g: EOT ->
(A)
(3 sec)