Communication S7-300/400 with ControlLogix

Thanks Fritz for your answer.
In that documents the communication related to Ethernet is using ISO Protocol but I want to use TCP/IP protocol on Siemens side.

Thanks

TCP is a stream-oriented protocol. It is permitted to send almost any length IP packet it chooses.
If two messages were passed to a TCP/IP stack, the TCP/IP stack may choose to put both messages in one Ethernet frame.
Alternatively it may choose to place half of the first message in the first Ethernet frame and all the rest in the next Ethernet frame. There is no EOM (end of message) recognition.

H1 (ISO) is a message-oriented protocol. There is EOM recognition. Messages arrive at the destination exactly in the same form they have been sent from the sender. Input block and Output block are identical.

The only thing you need to look out for is that you canNOT configure an"ISO on TCP connection" in NETPROfor the onboard PN port.
They do nonetheless support ISO on TCP (as of firmware 2.4 for S7-300 CPU's from memory), but you need to go the "Open TCP/IP Communication".
There is a wizard available to make the setup of these easier, have a look "Generating the Connection Data for the open TCP/IP Communication using the Open Communication Wizard" for more.

I hope this helps

cheers

fritz