Pipelined methods and apparatus for weight selection and content addressable memory searches

摘要

When a search key is supplied to a content addressable memory (CAM), the CAM signals indicate which CAM entries have matched the key. These signals are provided to a weight array to select the entry of the highest priority. Each entry's priority is indicated by a weight in the weight array. The weight array processing is pipelined. In pipeline stage 0, the most significant bits (bits 0) of the weights are examined, and the highest priorities are selected based on the most significant bits. At pipeline stage 1, the next most significant bits (bits 1) are examined, and so on.