Number of Simultaneous Connections
The maximum number of simultaneous TCP/IP connections to a TSX ETY 5103 is:
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32 if the high byte of the INTE is set to 00;16 can be connected (client) sockets and 16 can be listening (server) sockets.
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64 if the high byte of the INTE parameter is set to 01. The 64 socket can be used as listening (server) sockets or connected (client) sockets in any combination with one exception—in a server application, at least 1 socket must be a listening socket.
The maximum chunk of data that can be sent in one PLC cycle is 240 bytes. This limitation is due to the X-bus mechanism for data transfer between the module and the processor.
If you wish to transfer a message of 8 Kbytes, you must break down your message into blocks of 240 bytes. If you want to guarantee the order in which the blocks are sent so as to be able to reconstitute the whole message, you must send one block for each cycle. That means that 35 PLC cycles (8*1024/240) would be required. A PLC cycle of 50 ms would take 1.75 s.
NOTE: These calculations are based on the use of a single socket. If you are managing several clients, you must take into account the number of connected sockets.
For a message oriented protocol, a lower level interface has to manage the fragmentation process. Here performance depends on the number of
FCT_SEND or
FCT_RECEIVE functions executed in the same PLC cycle.
Performance can be reduced depending on the degree to which the TSX ETY 5103 module is used for other communications tasks (IO Scanning, Global Data, etc.).
