Omron V330-F Series Connection Manual page 39

9.1.1. Communications Data Flow
This is the flow from issuing a TCP socket communications command from the PLC (Ethernet
Unit) to the code reader and receiving response data from the code reader. The software part
executes a processing sequence of TCP open to TCP close in a continuous manner. If response
data is divided and arrives as multiple pieces of receive data, receive processing will be repeated.
Also, there are cases where there is no response data depending on the code reader or send
command. In such as case, receive processing can be skipped by setting the receive processing
required/not required setting to "receive processing not required" in advance.
* If the receive processing required/not required setting is set to "receive processing required", in send processing,
the program waits for the arrival of receive data before going to receive processing.
immediately after send processing.
1. TCP Open Processing
2. Command Send Processing
* If "receive processing required" is set, the
Ethernet Unit waits for response data to arrive.
3. Response Receive Processing
* If response data is divided and arrives in
pieces, the Ethernet Unit repeats receive
processing.
* If "receive processing not required" is set,
the Ethernet Unit skips receive processing.
4. Close Processing
If the setting is "receive processing not required", the program goes to close processing
The Ethernet Unit issues a TCP open request to the
code reader to establish a TCP connection.
▼
The Ethernet Unit issues a send message that is set
in the ladder program to the code reader and receives
response data.
▼
The Ethernet Unit stores the response data received
from the code reader in the internal memory of the
specified CPU Unit.
▼
The Ethernet Unit issues a close request to the code
reader to close the TCP connection.
9. Software Part
39