I have an inventory application (in C#.net) that uses the Modbus protocol to control the locks on a separate cabinet. The application controls the lock and reads the state of the lock. The problem is that I need to connect my computer to the cabinet in order to properly test and potentially debug the application. Is there any way to obtain or develop another application that emulates the cabinet hardware? I was thinking that I could open a cabinet application that would display when a door is unlocked or locked successfully while I am debugging my inventory application. Or is there a hardware device available that could do the same thing?