A program counter circuit is composed of two kinds of registers, a down counter, an up counter, a selector, and a logic circuit. The two kinds of registers hold a pre-jump PC value and a post-jump PC value of a jump that is prescribed by a program. The down counter holds the number of repetitions of...http://www.google.de/patents/US6930931?utm_source=gb-gplus-sharePatent US6930931 - Program counter circuit
