The PC parallel port break-out board was developed by James Cullins. James is the owner of Sound Logic in Grapevine Texas. The picture is of Rev level 1.8A.
The question that I get asked once in awhile is: Why do I need a break-out board? The options are, solder directly to a DB25 connector. I have done this and it creates a lot of wiring that is hard to manage. The next option is to buy a DB25 to terminal strip converter board ($35 to $45). The converter board is a lot better than soldering directly to a DB 25 connector.
Both option have their drawbacks which are addressed with the features in a break-out board.
The first and very important feature is isolation. The break-out board provides total optical isolation of the parallel port from the power supply and the equipment being controlled. If high voltage is inadvertently applied to any lead on the parallel, it most likely will burn out something inside the PC. With the break-out board, the parallel port is isolated. Voltage can burn out parts in the break-out board, which can be replaced.
The break-out board was designed to interface to the Gecko drives and inductive proximity sensors or standard micro switches. In the case of the Gecko drives, the board provides the 5 volts needed to power the optical isolators in the Gecko drives. The board also has a switch that will allow it to interface to other drives that want the ground connected to the PC ground.
The break-out board has screw terminal for all signals. In most cases, a led is also present on most lines.
The break-out board contains three power supplies. One 5 volt supply is used to provide 5 volts to power the optical isolators in the Gecko drives. A 12 volt power supply is provided to supply power to the proximity sensors. A second 5 volt supply is provided to convert the output from the proximity sensors back to 5 volts before it is sent back to the PC.
The input connector is a 26 pin duel in-line connector. The 26 pin connector is connected (ribbon cable) to a 25 pin parallel port connector which would mount on the outside of your control box.