A programmable logic array device in which programmable logic regions are arranged in groups of four is provided. The device includes direct connect conductors for carrying signals totally within one group of four regions as well as to certain adjacent programmable logic regions, local conductors for...http://www.google.com/patents/US5537057?utm_source=gb-gplus-sharePatent US5537057 - Programmable logic array device with grouped logic regions and three types of conductors
