12 SBC-456/456E User Manual132Open Closed Closed 2-3Open Closed Closed 2-31 2 3Setting jumpersYou configure your card to match the needs of your application bysetting jumpers. A jumper is the simplest kind of electric switch. Itconsists of two metal pins and a small metal clip (often protectedby a plastic cover) that slides over the pins to connect them. Toclose a jumper you connect the pins with the clip. To "open" ajumper you remove the clip. Sometimes a jumper will have threepins, labeled 1, 2, and 3. In this case you would connect either pins1 and 2 or 2 and 3.The jumper settings are schematically depicted in this manual asfollows:A pair of needle-nose pliers may be helpful when working withjumpers.If you have any doubts about the best hardware configuration foryour application, contact your local distributor or sales representa-tive before you make any changes.