When you want to connect the Siemens S/M7-300 you will need to
declare the hmi, you want to use, in the PLC, and vice versa.
In other words you need the proper drivers loaded in each device, plc and hmi, in order for them to be able to communicate.
For more information on hmi's you could take a look at www.esamhi.com. This to to give you an idea on what is possible with hmi's.
On the other hand you could also take a look a the following book, to become an expert on Siemens S/M7-300, and the coupling with an hmi: "STEP 7 in 7 Steps - A Practical Guide to Implementing S7-300/S7-400 Programmable Logic Controllers, 1st Edition " http://www.amazon.com/gp/product/18...=1789&creative=390957&creativeASIN=1889101036