A keycode data structure includes a device type byte, a set of keycodes, system code information, a system data byte, a protocol pointer that points to a protocol table and a number of flagbytes that are used to index a particular key among the keycodes. The keycode data structure also contains a plurality of keycode data structure pointers (KDSPs). Keycode data structures are linked together using KDSPs. A special value in the keycode data structure is used to indicate that the keycode data structure contains multiple KDSPs. The number of pointers is stored in a particular location of the keycode data structure.