Cypress Semiconductor Corporation

Avago Technologies International Sales Pte. Limited

Netlogic Microsystems, Inc

Rochan Sankar

Christopher W Jones

Haneef D Mohammed

Mohan V Kalkunte

Srinivasan Venkatachary

Eric H Voelkel

Andrew J Wright

Surendra Anubolu

A network switch for network communications includes an embedded programmable state machine to monitor data flows through the switch. The programmable state machine is configured to retain selectable states of selectable data packet fields. Programmable switch logic operative with the programmable state machine is configured to output one or more potential actions to be taken based on a selectable computation of detected selectable states. The programmable state machine can be implemented with either table lookups or flexible logic.

Flexible flow table with programmable state machine

A CAM and method for operating a CAM are presented. Copies of a CAM database are duplicated and placed in a first set of CAM locations and a second set of CAM locations. An error detector is used to determine false matches in the case of soft errors within the entries producing those false matches. While the entries producing a match should have the same index location, errors might cause those match lines to have an offset. If so, the present CAM, through use of duplicative sets of CAM locations, will detect the offset and thereafter the values in each index location that produces a match, along with the corresponding parity or error detection encoding bit(s). If the parity or error detection encoding bit(s) indicate an error in a particular entry, then that error is located and the corresponding entry at the same index within the other, duplicative set of CAM locations is copied into the that erroneous entry. Since duplicative copies are by design placed into the first and second sets of CAM locations, whatever value exists in the opposing entry can be written into the erroneous entry to correct errors in that search location. The first and second sets of CAM locations are configurable to be duplicative or distinct in content, allowing error detection and correction to be performed at multiple user-specified granularities. The error detection and correction during search is backward compatible to interim parity scrubbing and ECC scan, as well as use of FNH bits set by a user or provider.

Error correcting content addressable memory

A method for computing a sum or difference and a carry-out of numbers in product-term based programmable logic comprising the steps of: (A) generating (i) a portion of the sum or difference and (ii) a lookahead carry output in each of a plurality of logic blocks; (B) communicating the lookahead carry output of each of the logic blocks to a carry input of a next logic block; (C) presenting the lookahead carry output of a last logic block as the carry-out.

High performance carry chain with reduced macrocell logic and fast carry lookahead

A programmable logic block in an integrated circuit comprising a plurality of macrocells, an AND-array, an OR-array, and a logic circuit. The plurality of macrocells may comprise logic that may be configured to (i) generate and propagate an inverted carry-input signal and (ii) generate a sum bit. The AND-array may comprise at least two product terms per macrocell. The OR-array may be configured to generate a sum-of-products term for each macrocell in response to the two product terms. The logic circuit may be configured to (a) receive (i) the product terms and (ii) the carry-input signal generated by a first macrocell of the plurality of macrocells and (b) generate (i) a block carry-propagate signal, (ii) a block carry-generate signal, and (iii) a block carry-output signal.

A logic section of a programmable logic device comprising a first circuit and a second circuit. The first circuit may be configured to (i) implement user defined programmable logic and (ii) generate an output in response to a first input and a second input. The second circuit may be configured to generate the second input in response to the output, a third input, and a fourth input.

Multiplexers for efficient PLD logic blocks

A logic section of a programmable logic device comprising a first circuit and a second circuit. The first circuit may be configured to generate a first output in response to a first input, a second input and a third input. The second circuit may be configured to generate a second output and a third output in response to a fourth input and a fifth input. The second output may be coupled to the second input and the first output may be coupled to the fifth input.

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San Jose, CA, United States of America

Rochan Sankar