Communications Procedure; Command Communications Procedure - Omron V780 Series User Manual

7 Modbus/TCP Communications
7-4

Communications Procedure

In the computer, PLC, or other host devices, write the program to communicate with the Reader/Writer
using TCP sockets.
If you use an Modbus/TCP master device, follow the communications procedure for the device you are
using.
7-4-1

Command Communications Procedure

A connection is required between the host device and Reader/Writer to communicate with the
Reader/Writer. After you establish a connection, send commands and receive the responses.
1
Connection Processing: Opening a Socket
Send a request for a connection from the host device to the Reader/Writer and establish a TCP
connection. Monitor for connection timeouts as required.
2
Command Send Processing: Sending Socket Data
Send the command from the host device to the Reader/Writer in a message.
Monitor for send timeouts as required.
3
Response Reception Processing: Receiving Socket Data
At the host device, wait to receive the message from the host device and receive the response.
Monitor for reception timeouts as required.
4
Disconnection Processing: Closing the Socket
Send a request for a disconnection from the host device to the Reader/Writer and disconnect
the TCP connection. Monitor for disconnection timeouts as required.
Host device
(client)
7 - 12
Connection requested.
Connection request acknowledged.
Command sent.
Response returned.
Disconnection requested.
Disconnection request acknowledged.
Reader/Writer
(server)
UHF RFID System V780-series Reader/Writer User's Manual (Z389)