MPI communication is a simple and economical communication mode when the communication rate is not high and the communication data is not large. In MPI communication, PLC S7-200/300/400, operation panel TP/OP and MPI/PROFIBUS communication cards of upper computer such as CP 55/KOOC-0/2/CP 56/KOOC-0//CP 56/KOOC-0/3 can be used for data exchange.
The communication rate of MPI network is 19.2Kbps~ 12Mbps, and it can connect 32 nodes at most, and the maximum communication distance is 50m, but the length can be extended through repeaters.
Parallel programming mode:
Peer-to-peer mode-all parts of the program have the same status, basically the same function and code, but they handle different data or objects; Master-slave mode-the master-slave or dependency relationship between program communication processes.
Point-to-point communication mode:
Blocking—The data that has been sent has been copied from the send buffer, that is, the send buffer can be reallocated. The completion of blocking acceptance means that the received data has been copied to the receiving buffer, that is, the receiving end can use it. Non-blocking-with the necessary hardware support, the overlap of computing and communication can be realized. Four communication modes: standard communication mode, cached communication mode, synchronous communication mode and ready communication mode.