MPI Serial Communication Protocol

[Jay Anthony 118]

Anyone have any idea about the similarity between the TI and Siemens HMI serial communication protocols? They are both called MPI. Are they the same?

[Guest Roy Robbins]

Not even close. The TI communication was RS232 or RS485 and ASCII protocol. The MPI used by the S7 line is Profibus protocol and you have to purchase ProDavi to get the protocol.

[Seppo Alanen 0]

MPI is Multi Point Interface. In S7, MPI not use Profibus protocol? When using Profibus-DB for programming, it uses MPI-protocol inside the ProfibusDB protocol. ?? PPI is point to point Interface for RS232C ? So is it the same ? Could be ?

[Guest The MPI protocol is still a myst]

However I am very familiar with the TI protocols. Actually there are two TI protocols. The ASCII protocol is call NITP (non intelligent terminal protocol). The binary and newer protocol is called TBP ( transparent byte protocol). What is interesting about the TBP is that it uses the fletcher checksum which is a interesting and one of the best forms of checksum. With the NITP and TBP, I have been able to two write my own interfaces to the TI but that was long ago. The little I do know about MPI is close to what Roy has said. It is just a Profibus type of interface with a application layer on it.