In some applications of shift counters, self initialization is an advantage. It eliminates the need for complex initialization and guarantees the return to the original state sequence after a temporary failure. The low operating frequencies and large areas of the available self correcting shift counters, however, impose severe limitations to their use. This poor performance is partially due to a widely used design method. It consists of modifying the state diagram of a counter with the desired modulus until a single cycle is left. Due to the additional hardware required to change state transitions, the final circuit tends to be slow and large. The paper presents a technique for determining self correcting shift counters by selecting the feedback functions from a large set of functions. The set is searched for functions satisfying a minimization criterion. Self correcting shift counters with up to 10 stages have been determined. These counters are faster and smaller than the self correcting shift counters available from the literature. A table of self correcting shift counters with 6 stages is included in the paper.
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