ما الفرق بين PPI MPI Profibus PA DP

السلام عليكم ورحمة الله وبركاته
ممكن جزاكم الله خيرا توضيح الفرق بين PPI - MPI - Profibus PA - DP لانه اخلتط عليا كل شيء

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Entry type: FAQ, Entry ID: 85669627, Entry date: 04/29/2014 (3) Rate
What should you watch out for with the PPI/MPI/DP interfaces if you want to use the CP 5711 with a SIMATIC S7-200?
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Description
The SIMATIC NET CP 5711 is an onboard PB module in the Field PG M4 and when used for an S7-200 you must note the following system properties with regard to the PPI/MPI/PROFIBUS interfaces.

PPI:
The PPI protocol is not supported by software drivers through the CP 5711.
Note
Use the PROFIBUS setting with the universal profile.
MPI:
Use of the MPI (Multi Point Interface) is possible with restrictions. On the PG side you can set transmission rates of 187.5 kbit/s and 19.2 kbit/s. These baud rates are preset in the S7-200. In the STEP 7-Micro/WIN software the baud rate is to be set to that set on the CPU22x.
Note
For successful communication setup between PG and S7-200, in STEP 7-Micro/WIN you check the option "Only master on the bus".
The baud rate 9.6 kbit/s is not possible with MPI.
DP:
Use of PROFIBUS DP is possible and works with transmission rates of 9.6 to 187.5 kbit/s.
Further information about SIMATIC NET PROFIBUS CP 5711 is available in Entry ID: 34803449.

S7-200 was developed by and for SE&A USA to compete with
other manufacturer's similar products. and S7-300 and 400 by Siemens AG germany to
replace SIMATIC S5, with entirely different target markets and applications.

Yoy are right calling PPI as "Point to Point" is basically a misnomer because in PPI network
also you can have several PLCs and HMIs. It is correct that PPI is basically a glorified RS485
networking. Basically it is meant for slow speed communication for short data packets.

MPI However works on a different principle. It is loosely based on Profibus standard but some additional features like Global data communication etc have been added and DP feature has
beenremoved. I guess this waythere is no need to use costly "Profibus" chips.