The parallel port (a.k.a. printer port) may be one of the most crucial types of interfaces on your computer. To be on top of what is happening with it, it is recommended that you download and use Parmon. Parmon is a very useful Windows-based Freeware program which takes up a very little space on your hard disk. It enables you to monitor each and every individual bit/line of the parallel port. It even lets you set up the behavior of the bits/lines. You can view or modify the port registers with the help of an easy to understand graphical interface which shows a representation of the port connector, as individual bits, hex values and decimal values. It also has a setting that produces a beep when a port changes.