produce a custom circuit board with external 12v power for a 12v buzzer something like [url removed, login to view]
The circuit board should be able to connect to a windows 7 pc via USB.
A simple software is required to activate the buzzer. Poll a file [url removed, login to view] every 500ms. If 1, beep. if 0 no beep.
The software can be an exe. but best if it can be written in perl.
I have a vast experience of working on Embedded projects. I'm an electronicss engineer. I can make this project with efficiency, and deliver on time.