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6.4.1 The number of TCP-IP connections
The MSD can connect up to eight connections (8 ports) simultaneously. If the MSD is controlled from nine or
more PCs, they may not be connected to the MSD.
For nine or more connections, use your software to establish and close TCP-IP connections for each sending
and receiving communication commands. By doing so, connections are occupied and released in the MSD
side so that logically eight or more connections (eight or more ports) can be connected.
Your PC software
MSD-5404
TCP-IP
connection
→
(1 port is occupied
→
7 ports free)
Sending command
(@xxx)
→
←
Sending reply command (@xxx)
TCP-IP close
→
(1 port is released
→
8 ports are free)
[Figure 6.6] Increasing connections
Note:
If any command is not sent from the PC side to the MSD for 30 seconds, the MSD disconnects the connection
to avoid the limitation problem on the number of connections. As a result, the 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 MDS-54 series is eight, if the PC is turned off while it is connected, ports are occupied
permanently. To prevent this, the connection is disconnected if no communication command is sent from the
PC side.)