
FINS/TCP Method | Section |
FINS/TCP Connection Status (Word n+23)
While a connection with a remote node is established, the bit corresponding to the FINS/TCP connection status turns ON in the section of the CPU Bus Unit words allocated in the CIO Area. The bit turns OFF if the connection is termi- nated by an error in communications with a remote node or a FINS command (i.e., FINS/TCP CONNECTION REMOTE NODE CHANGE REQUEST).
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
n+23
*: Bit 15 corresponds to connection No. 16, bit 00 to connection No. 1, etc.
FINS/TCP | With FINS/TCP, FINS node addresses are exchanged immediately after a |
Communications | connection is established. This makes it possible to determine the FINS node |
Procedure | addresses to which the 16 connection numbers are connected, and to man- |
| age them in an internal table. |
Personal computer
(Client)
Example:
IP address C
FINS node address A
Active open
Ethernet Unit
(Server)
Example:
IP address S
FINS node address B
Passive open
Connection request (C→S)
Connection established
Connection established
Local node address sent
FINS node address A sent
Connection established
Remote node address received
Remote node address received
FINS frame sent
FINS node address B sent
Local node address sent
FINS frame sent
Full duplex communications
FINS node addresses exchanged
Normal data communications
After a connection has been established as a FINS/TCP server, it is termi- nated in the following ways.
•When the connection is closed by the client.
•When a FINS command to close the connection (FINS/TCP CONNEC- TION REMOTE NODE CHANGE REQUEST: command code 27 30 hexa- decimal) is sent by the client.
•When there is no response from the client when the
•If a command other than FINS FRAME SEND is received from the client, the connection will close after the FINS FRAME SEND ERROR NOTIFI- CATION command is sent.
After a connection has been established as a FINS/TCP client, it can be termi- nated in the following ways.
• If the connection is closed by the server.
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