Partial update in a ternary content addressable memory

摘要

A TCAM may have a plurality of rows of cells. Each row may have a match line. Each cell may have elements for storing first and second bits, and compare circuitry associated to determine matches between a bit of a search word and data stored in the cell. For at least one first row of the rows, the TCAM includes a valid row cell having at least one element to store a partial update indication. The valid row cell may cause the match line associated with the first row to signal that the first row does not match a search word when the partial update indication associated with the first row is enabled. When the partial update indication associated with the first row is disabled, the determination of matches with a search word is performed solely by the compare circuitry without influence of the valid row cell.

主权项

1. A ternary content addressable memory (TCAM), comprising:
a plurality of rows of cells, each row having a match line, each cell having elements for storing first and second bits; compare circuitry associated with each cell to determine matches between a bit of a search word and data stored in the cell; and a valid row cell for at least one first row of the rows, the valid row cell having at least one element to store a partial update indication, the valid row cell to cause the match line associated with the first row to signal that the first row does not match a search word when the partial update indication associated with the first row is enabled.