The only tool that I know of, which is still available is Test Quest. http://www.testquest.com
I guess it depends on the operating system which the POS uses. If it's windows, then there are other tools such as WinRunner which will work. But Test Quest is a semi non-invasive tool which works with POS and ATM systems. X-Runner also used to be such a tool, but I'm not sure it is still on the market. TestRunner by Qronus was the best, but it is no longer available.
Success is the ability to go from one failure to another with no loss of enthusiasm.
~ Winston Churchill ~