S7 PLC training manual

Can anyone help explain how S7 PLC are constructed and utilises a profibus connection in industry. Also basic PLC functions such as plugging in a laptop, setting the MPI connections, start stop, cpu key switch.
I have step 7 software but not PLC to practise on. I also need explaining the use of cross reference, data, and program structure.

Thanks

Tom

Hello Paul;
There are many levels of answer possible for your request. I can suggest manuals (either at www.ad.siemens.de or on the computer that Step 7 is installed on [pdf files are installed automatically]).
The manual that seems to answer most of your questions is called "Step 7-Configuring Hardware with Step 7"; it is found in the following directory on my computer:
C:\Siemens\Step7\S7MANUAL\S7HWV5_A\s7hw51_b.pdf
Look for it in the appropriate path on your Step 7 computer. Come back to us with more precise questions as they come around.
Hope this helps,
Daniel Chartier