Omron CS1W-ETN21 operation manual Executing CMND490 Improved TCP Socket Interface

Overview of Communications Functions Section 1-5

Executing CMND(490)

Improved TCP Socket Interface

A total of eight ports (UDP and TCP combined) can be used for socket ser- vices.

UNIX computer, etc. (node with socket services interface)

		Ethernet
			Ethernet Unit
	TCP/UDP
	protocol
CS/CJ-series
CPU Unit

IP	TCPUDP	Socket	Service request switch
TCP/UDP			Parameters
protocol

Ethernet Unit CS/CJ-series

CPU Unit

Another way to use socket services is to request a UDP or TCP socket ser- vice by sending a FINS command to the Ethernet Unit by executing CMND(490) from the CPU Unit. When the Ethernet Unit receives the socket service request, it returns a response to the CPU Unit to confirm that it received the request, and then begins the requested processing. When the processing is completed, the results are stored in the Results Storage Area in the CPU Unit.

Eight TCP ports and eight UDP ports can be used.

The TCP socket interface has been improved. The size of received data accu- mulated in the reception buffer is now stored, and a Data Received Flag has been added, enabling the TCP socket's receive program to be executed after the required data has been accumulated in the Ethernet Unit's reception buffer. The keep-alive setting has also been enabled for TCP socket services.

UNIX computer, etc. (node with socket services interface)

	Ethernet
TCP/UDP		Ethernet Unit
protocol

CS/CJ-series

CPU Unit

				FINS
		UDPTCP		commands	CMND
			Socket
TCP protocol	IP			FINS	Results Storage
				responses
					Area
UDP protocol				Processing
				results
	Socket interface

Ethernet Unit CS/CJ-series

CPU Unit

19