COMPLETELY UTILIZING HAMMING DISTANCE FOR SECDED BASED ECC DIMMS

摘要

In an Error Correction Code (ECC)-based memory, a Single Error Correction Double Error Detection (SECDED) scheme is used with data aggregation to correct more than one error in a memory word received in a memory burst. By completely utilizing the Hamming distance of the SECDED (128,120) code, 8 ECC bits can potentially correct one error in 120 data bits. Each memory burst is effectively “expanded” from its actual 64 data bits to 120 data bits by “sharing” additional 56 data bits from all of the other related bursts. When a cache line of 512 bits is read, the SECDED (128,120) code is used in conjunction with all the received 64 ECC bits to correct more than one error in the actual 64 bits of data in a memory word. The data mapping of the present disclosure translates to a higher rate of error correction than the existing (72,64) SECDED code.

主权项

1. A method comprising:
receiving a burst-specific content from each burst in a plurality of bursts from a memory module, wherein the burst-specific content includes a first pre-determined number of bits of burst-specific data along with corresponding bits of burst-specific Error Correcting Code (ECC); storing the burst-specific content from each burst in the plurality of bursts; and using all received ECC bits as part of a Single Error Correction Double Error Detection (SECDED) code to correct more than one error in the first pre-determined number of bits of burst-specific data from at least one of the plurality of bursts.