There's no official documentation about this. I think if you inspect the communication using wireshark, you can see many things of what's going on. For S7comm-plus you'll need a plugin dll which I provide here at sourceforge. But with current controllers the communication is encrypted, and you wont't see much of the details.
In this project you'll find no information about the S7 protocols, as it tunnels the Iso-On-TCP payload into the internal S7Online-Interface, whithout processing the details. Only S7comm parts are processed to create debug outputs of the requested memory areas.
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Hello, I need information about the format of S7 frames over TPKT.
There's no official documentation about this. I think if you inspect the communication using wireshark, you can see many things of what's going on. For S7comm-plus you'll need a plugin dll which I provide here at sourceforge. But with current controllers the communication is encrypted, and you wont't see much of the details.
In this project you'll find no information about the S7 protocols, as it tunnels the Iso-On-TCP payload into the internal S7Online-Interface, whithout processing the details. Only S7comm parts are processed to create debug outputs of the requested memory areas.