Toshiba T2N instruction manual Rclos

6 F 3 B 0 3 6 2

8.4 Socket Interface Information

The information for the eight socket interface sockets held by the Ethernet Port can be read out with the T2N READ instruction. (See Section 6.3 Socket Interface Information.) The Ethernet Port holds five words of socket status information for each socket.

∙Remote port TCP/UDP port number

∙Remote port IP address

∙TCP/UDP port number for this socket

∙Socket status

Table 8.7 lists the structure of the socket interface information and the extended memory area addresses.

Table 8.7 Socket Interface Information

	Socket identifier
	1	2	3	4	5	6	7	8
Remote port number (TCP only)	0F4BH	0F53H	0F5BH	0F63H	0F6BH	0F73H	0F7BH	0F83H
Remote port IP address (TCP only)	0F4CH	0F54H	0F5CH	0F64H	0F6CH	0F74H	0F7CH	0F84H
	0F4DH	0F55H	0F5DH	0F65H	0F6DH	0F75H	0F7DH	0F85H
Local port TCP/UDP port number	0F4EH	0F56H	0F5EH	0F66H	0F6EH	0F76H	0F7EH	0F86H
Socket status	0F4FH	0F57H	0F5FH	0F67H	0F6FH	0F77H	0F7FH	0F87H

For UDP sockets, the remote port number and IP address data are invalid.

The socket status has the following structure.

			F E D C B A 9 8 7 6 5 4 3 2 1 0
			TCP		AOPEN		CONN	RCLOSE
				UDP		POPEN RCV			NOACK
Bit no.	Bit	Condition under which the bit is set to 1								Condition under which the bit is reset to 0
F	TCP	TCP used by the socket								The socket closed in response to a close request
E	UDP	UDP used by the socket								The socket closed in response to a close request
D	AOPEN	TCP socket in active open state								The socket closed in response to a close request
C	POPEN	TCP socket in passive open state or UDP								The socket closed in response to a close request
		socket in open state
B	CONN	TCP connection established								Disconnected by the local port with a close request
										Disconnected by the remote port
A	RCV	Received text present								No received text
9	RCLOS	An established TCP connection disconnected								The socket closed in response to a close request
	E	by the remote port
8	NOACK	No response received from the remote port for								The socket closed in response to a close request
		a local port send operation in a state where a
		TCP connection was established, and the TCP
		resend function resulted in a timeout (because
		the remote port was down, etc.).
		If the wait time exceeds the set value during a								When a TCP active open request is reissued.
		TCP active open request.
		This state does not occur for TCP passive
		open requests.

A socket status in which neither AOPEN nor POPEN is set to 1 indicates that the socket is in the closed state.

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