Some printers have a switch (or function) that allows you to select between the optional and original interface. If you install the C82310* interface card in this type of printer, set the interface card’s DIP switch 2 to ON and also change the setting in the printer to select the optional interface.
Jumpers
A jumper is a small plug used for connecting or disconnecting a circuit. The jumper is on when the jumper plug covers both wires of the terminal. Jumper settings can be changed by either attaching or removing the rectangular jumper plug. If the jumper is to be turned off, connect it to only one of the two terminal pins as shown in the figure below. This prevents your losing the unused jumper plug.
Figure 2. Jumpers
7