FDX-16 Command Guide
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2.2.4 The number of TCP-IP connections
The FDX series can connect up to eight connections (eight ports) simultaneously. If the FDX is controlled from
nine or more PCs, they may not be connected to the FDX normally, since the number of connections that can
be used simultaneously is limited.
If you use nine connections or more, TCP-IP connection will be executed/closed every time the
communication command is sent or received from the software of user
’s side. By doing so, FDX’s ports are
occupied or released so that nine or more connections can be connected logically.
[Table 2.3] Increasing connections
Your PC software
FDX-16
TCP-IP connection
→
(1 port occupied)
Send command (@xxx)
→
←
The command (@xxx) replied
TCP-IP close
→
(1 port released)
Note:
If any command is not sent from the PC to the FDX for 30 seconds, the FDX disconnects the
connection to avoid the limitation problem on the number of connections. As a result, connection needs
to be established again from the PC side after the current connection of the PC is disconnected.
(Since the number of ports in the FDX is eight, ports are occupied permanently if the PC is turned off
while connections are valid. To prevent this, the FDX disconnects connections if no communication
command is sent from the PC side.)
