Hello kaushik;
Here is a short example of using Profibus-DP to control a Siemens MicroMaster 4 drive:
http://support.automation.siemens.com/WW/view/en/8894363
Note that thjis example only applies to this specific drive. Even Siemens MasterDrives and Sinamic drives require modifications of this example for the Profibus link to work. And other manufacturers have different implementations of the Profibus connection, so you would hgave to study their communication manuals.
But basically, there are common steps:
-Introduce the gsd file (from the drive manufacturer) into the profibus configurator;
-Insert a drive into the configurator's Profibus network; select a valid Profibus address for the slave drive;
-select input/output modules to exchange data between the master and the slave drive (for the MM4, this would be one of the PPOx telegrams); adapt the master's input/output addresses to match the size of the exchange table selected;
-program the master to read/write to the drive; here you must understand the specific requirements that the drive needs to start, stop, accelerate.... Use the previously selected input/output addressing to exchange the required data.
Study the example provided and then try to understand the steps I just described, you should be able to understad the basics.
Hope this helps,
Daniel Chartier