Tcp/Ip Communications Programming Example; System Configuration - Omron CS CJ1W-ETN21 Operation Manual

Using Socket Services with CMND(490)
6-8-8

TCP/IP Communications Programming Example

System Configuration

■
CLOSE REQUEST during RECEIVE REQUEST
Port Enabled Flag
CMND(490) (RECEIVE REQUEST)
response command
CMND(490) (CLOSE REQUEST)
response command
Receive Flag
Close Flag
Opening Flag
Results storage area for
RECEIVE REQUEST
Results storage area for
CLOSE REQUEST
Note The timing shown in the above diagram occurs if a CLOSE REQUEST com-
mand is executed during SEND REQUEST command execution. The timing
shown in the diagram also applies if a CLOSE REQUEST command is exe-
cuted during OPEN REQUEST command execution, with the exception of the
status of the Opening Flag.
The following programming example illustrates transferring 100 bytes of data
between an Ethernet
communications.
The system configuration for the program example and the Ethernet Unit
system setup are shown below. To establish a TCP connection, the Ethernet
Unit is passively opened and the host computer actively opened.
Host computer
IP address:
Port number: 4096
RECEIVE REQUEST CLOSE REQUEST
command received command received
1
Running
0
Normal response code
1
0
1
0
1
0
Unit and a
Ethernet Unit
196.36.32.55 IP address:
Port number:
FINS network address:
Node address:
Unit number:
Section 6-8
Running
Normal response code
Store error response code
Store normal response code
host computer using
PLC
196.36.32.101
4096
01 Hex
01 Hex
10 Hex
TCP/IP
141