Chapter 7 Automatic Sending/Receiving function (ASR)
7.2.1 Open connection
The procedure for opening connection is shown as Figure 7.7.
EH-ETH2
(A-2)
Host PC
(A) In case of active open setting
(A-1)
(A-3)
EH-ETH2
(B-1)
Host PC
(B) In case of passive open setting
(B-2)
(B-3)
(A) In case EH-ETH2 is in active open
Description Segment
EH-ETH2
internal status
(A-1)
EH-ETH2 requests active open against host PC of passive
open status.
Sending SYN flag
Sending request to
connect
(SYN-SENT )
(A-2)
Host PC receives the request to connect from
EH-ETH2,
sends a reply of ready to open connection to EH-ETH2, and
waits ACK from EH-ETH2.
Sending SYN ACK
flag
-
(A-3)
EH-ETH2
receives the reply from the host PC, and sends
back ACK.
Sending ACK flag
Connection opened
(ESTABLISHED )
(B) In case EH-ETH2 is in passive open
Description Segment
EH-ETH2
internal status
(B-1)
Host PC requests active open against EH-ETH2 of passive
open status.
Sending SYN flag
(B-2)
EH-ETH2 receives the request to connect from Host PC,
sends a reply of ready to open connection to Host PC, and
waits ACK from Host PC.
Sending SYN ACK
flag
Sending request to
connect
(SYN-RCVD)
(B-3)
Host PC receives the reply from the EH-ETH2, and sends
back ACK.
Sending ACK flag
Connection opened
(ESTABLISHED )
Figure 7.7
Basic procedure to open connection
Caution
- In case of the task code communication, the way to open is fixed as passive open.
- In case of ASR connection, the way to open is selected as active or passive, which can configured in EH-ETH2
Configurator only.
The each ASR parameters are set properly and EH-ETH2 is in active mode to open ASR connection.
In this explanation, EH-ETH2 is own station and the other equipment is other station.
The following items are "
ASR information"
.
(1) Select communication protocol
(2) Select active open or passive open
(3) Configure own logical port number
(4) Select specified or optional other station.
(5) Configure IP address of the other station (Only in case the other station is “specified”.)
(6) Configure Logical port number of the other station. (Only in case the other station is “specified”.)
ASR parameters are set in EH-ETH2 Configurator. Please refer to “Section 5.4” in details.
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