The onboard readers on a RKP-2220 do not require addressing, similar to readers attached to a RKP-1300 or RKP-1320. Instead, the reader Type will define its connection to the RKP-2220. Select Type "IDRC Onboard Reader 1" for the first reader and "IDRC Onboard Reader 2" for the second reader. Once these are selected, the Port and Address options will become grayed out.