PC Adapter is the important tool for working with a PLC instead a PG with Simatic Step 7 Software. It is the interface to communicate with PLC. By this tool we can setup a PLC with all the module connected, transfer a program, download and upload, and also monitoring the states of IO’s, etc.
The old PC Adapter used RS232 interface. But now, many laptop have some USB ports with no serial port. So USB port is the best choice.
When you are using Windows 7, you can’t install this driver.
All simatic software which are released for Windows 7 (like Step 7 5.5, TIA Portal V11) already have PC USB device driver. And will be installed automatically.