Single chip error processor

• US 5,537,421 A
• Filed: 10/07/1988
• Issued: 07/16/1996
• Est. Priority Date: 10/07/1988
• Status: Expired due to Term

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Dujari, Vineet, Copp, Larry A.
• Primary Examiner(s): Baker, Stephen M.
• Application Number:
  US07/255,016
• Time in Patent Office: 2,839 Days
• Field of Search: 371/37.1, 371/40.1
• US Class Current: 714/785
• CPC Class Codes: G06F 11/10 Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's
• CPC Class Codes: G06F 11/267 Reconfiguring circuits for testing, e.g. LSSD, partitioning
• CPC Class Codes: H03M 13/15 Cyclic codes, i.e. cyclic shifts of codewords produce other codewords, e.g. codes defined by a generator polynomial, Bose-Chaudhuri-Hocquenghem [BCH] codes H03M13/17 takes precedence

Abstract

An error processor on a single integrated circuit chip to detect and correct errors in a block of received data. The error processor includes processing hardware for receiving data and for generating syndrome bytes corresponding to the received data. It also includes processing hardware for detecting errors in the received data and for generating correction vectors to indicate the relative locations and error values thereof. An interface is connected to the processing hardware for facilitating data transfer to and from a communications bus.

Claims

1. An error processor for providing hardware syndrome generation and analysis, said error processor being disposed on a single integrated circuit chip to detect errors in a block of received data and to generate an error correction vector, said error processor being in communicative relationship with an external communications bus and comprising:

a) processing hardware means for;

i) receiving data and for generating syndrome bytes corresponding to said received data,

ii) detecting errors in said received data and for generating error correction vectors indicative of the relative locations of said errors and of the values thereof, and

iii) generating checkbytes as a function of the received data; and

b) interface means operatively connected to said processing hardware means and to said external communications bus for facilitating data transfer therebetween,

further comprising dummy vector generating means for generating a predetermined dummy error value in an error correction vector upon occurrence of an uncorrectable error.

2. The error processor in accordance with claim 1 wherein said interface means comprises a high speed data transmission interface and a register interface.

3. An error processor as recited in claim 1, wherein said interface means further comprises:

status indicating means for including in said error correction vectors a status indicator identifying a status of a correction operation.

4. An error processor for providing hardware syndrome generation and analysis, said error processor being disposed on a single integrated circuit chip to detect errors in a block of received data and to generate an error correction vector, said error processor being in communicative relationship with an external communications bus and comprising:

a) processing hardware means for;

i) receiving data and for generating syndrome bytes corresponding to said received data,

ii) detecting errors in said received data and for generating error correction vectors indicative of the relative locations of said errors and of the values thereof, and

iii) generating checkbytes as a function of the received data; and

b) interface means operatively connected to said processing hardware means and to said external communications bus for facilitating data transfer therebetween,

wherein said interface means further comprises;

status indicating means for including in said error correction vectors a status indicator identifying a status of a correction operation,

dummy vector generating means for generating a predetermined dummy error value in an error correction vector when said status indicator thereof identifies an uncorrectable error.

5. An error processor for providing hardware syndrome generation and analysis, Said error processor being disposed on a single integrated circuit chip to detect errors in a block of received data and to generate an error correction vector, said error processor being in communicative relationship with an external communications bus and comprising:

a) processing hardware means for;

i) receiving data and for generating syndrome bytes corresponding to said received data,

ii) detecting errors in said received data and for generating error correction vectors indicative of the relative locations of said errors and of the values thereof, and

iii) generating checkbytes as a function of the received data; and

b) interface means operatively connected to said processing hardware means and to said external communications bus for facilitating data transfer therebetween,

wherein said processing hardware means comprises a vector FIFO register for accepting said error correction vectors generated by said processing hardware means.

6. The error processor in accordance with claim 5, wherein said interface means comprises a record size register for specifying the length of said block of received data.

7. The error processor in accordance with claim 5, wherein said interface means comprises a threshold count register for specifying a maximum allowable number of errors to be corrected by an external error correcting means.

8. An error processor as recited in claim 5, wherein said vector FIFO register is internal to said error processor, and said error processor further comprises:

means for indicating a status of a correction operation, for identifying an error location, and for determining an error value;

means for including said status of a correction operation, said error location, and said error value in said error correction vector; and

means for generating a dummy vector when said status of a correction operation indicates a terminating status,

said error processor connected via said external communications bus to an external control means;

said means for including thereby providing to said control means in the dummy vector an indication of uncorrectable error status when an uncorrectable error occurs thus enabling said control means to reset control logic of said vector FIFO register.

9. The error processor in accordance with claim 5, wherein said interface means comprises a register file adapted to retrieve error correction vector data from said vector FIFO register.

10. The error processor in accordance with claim 9, wherein said interface means is adapted to generate a VECTOR BYTE AVAILABLE signal to indicate availability of an error correction vector.

11. The error processor in accordance with claim 5, wherein said interface means comprises a configuration register for specifying a number of subdivisions in said block of received data.

12. The error processor in accordance with claim 11, wherein said interface means further comprises an interleave size register for specifying the length of each of said subdivisions.

13. The error processor in accordance with claim 5, wherein said interface means comprises a status register for indicating completion of tasks and for indicating occurrence of uncorrectable errors.

14. The error processor in accordance with claim 13, wherein said interface means further comprises an interrupt mask register for selectively inhibiting generation of an interrupt signal when said status register is updated.

15. The error processor in accordance with claim 5, wherein said interface means comprises a control register for controlling operation of said processing hardware means.

16. The error processor in accordance with claim 15, wherein predetermined bits stored in said control register determine whether a data transmission (write) or a data reception (read) operation is to be performed.

17. The error processor in accordance with claim 15, wherein predetermined bits stored in said control register enable operation of said processing hardware means.

23. An error correcting system as recited in claim 17 wherein said control means comprises disk controller means for controlling transfer of data sectors between a disk and a storage device, said interface means comprises buffer means for storage of data being transferred, and said error processor comprises means for including data in said error correction vector for indicating relative locations of errors;

said disk controller means operable for computing a location in said buffer means of a byte having an error in accordance with the data provided in said error correction vector, fetching the byte from said location in said buffer means for correction of the error, and restoring the corrected byte to said location in said buffer means.

24. An error correcting system as recited in claim 23 wherein said processing hardware means further comprises means for simultaneously:

i) processing data for a first data sector to generate a syndrome therefor,

ii) processing a syndrome generated for a second data sector preceding said first data sector to generate an error correction vector for said second data sector; and

iii) storing an error correction vector generated for a third data sector preceding said second data sector.

18. An error correcting system, comprising an error processor for providing hardware syndrome generation and analysis, said error processor being disposed on a single integrated circuit chip to detect errors in a block of received data and to generate an error correction vector, said error processor being in communicative relationship with a communications bus and including:

a) processing hardware means for;

i) receiving data and for generating syndrome bytes corresponding to said received data,

ii) detecting errors in said received data and for generating error correction vectors indicative of the relative locations of said errors and of the values thereof, and

iii) generating checkbytes as a function of the received data; and

b) interface means operatively connected to said processing hardware means and to said communications bus for facilitating data transfer therebetween,

said communications bus further connected to a control means for controlling communication among a plurality of data sources;

said control means correcting errors in data transmitted from one of the data sources to another of the data sources,

c) said processing hardware means further comprising queue means for storing said error correction vectors and signal means for outputting a VECTOR BYTE AVAILABLE signal to said control means for informing said control means of availability of one of said error correction vectors thereby eliminating a requirement for polling or interrupts,

d) said control means being responsive to said VECTOR BYTE AVAILABLE signal by correcting an error identified by an error correction vector in said queue means.

19. An error correcting system as recited in claim 18, wherein said error processor further comprises:

an internal vector FIFO register for accepting said error correction vectors generated by said processing hardware means;

means for indicating a status of a correction operation, for identifying an error location, and for determining an error value;

means for including said status of a correction operation, said error location, and said error value in said error correction vector; and

means for generating a dummy vector when said status of a correction operation indicates a terminating status,

said control means being external to said error processor;

said means for including thereby providing to said control means in the dummy vector an indication of uncorrectable error status when an uncorrectable error occurs thus enabling said control means to reset control logic of said internal vector FIFO responsively thereto.

20. An error correcting system as recited in claim 18, wherein said interface means further comprises:

status indicating means for including in said error correction vectors a status indicator identifying a status of a correction operation.

21. An error correcting system as recited in claim 18, wherein:

said control means being external to said error processor, and

said interface means comprises dummy vector generating means for generating a predetermined dummy error value in an error correction vector upon occurrence of an uncorrectable error,

said dummy error value in said error correction vector providing to said control means an indication of uncorrectable error status when an uncorrectable error occurs in a block of received data.

22. An error correcting system as recited in claim 18 wherein said control means is responsive to assertion of said VECTOR BYTE AVAILABLE signal by:

a) fetching an error correction vector from said queue means;

b) computing a location of a byte having an error;

c) fetching the byte having the error;

d) correcting the error in accordance with data provided in said error correction vector; and

e) replacing the byte with the corrected error.

25. An error processor for providing hardware syndrome generation and analysis, said error processor being disposed on a single integrated circuit chip to detect errors in a sequence of blocks of received data and to generate an error correction vector, said error processor being in communicative relationship with an external communications bus and comprising:

a) processing hardware means for;

i) receiving data and for generating syndrome bytes corresponding to said received data,

ii) detecting errors in said received data and for generating error correction vectors indicative of the relative locations of said errors and of the values thereof, and

iii) generating checkbytes as a function of the received data; and

b) interface means operatively connected to said processing hardware means and to said external communications bus for facilitating data transfer therebetween,

c) said processing hardware means comprising;

means for simultaneously;

i) processing data for a first data block to generate a syndrome therefor,

ii) processing a syndrome generated for a second data block preceding said first data block to generate an error correction vector for said second data block; and

iii) storing an error correction vector generated for a third data block preceding said second data block, and

means for generating a VECTOR BYTE AVAILABLE signal to inform an external communications controller of availability of an error correction vector thus eliminating a requirement for polling or interrupts.

26. An error processor as recited in claim 25 further comprising an external control means connected to said external communications bus, said external control means operating for controlling data transfer among a plurality of data sources;

and wherein

said interface means comprises register means for storing control information for said error correction vectors and buffer means for storage of data being transferred;

said error processor further comprising means for including data in said error correction vector for indicating relative locations in said buffer means of bytes having errors; and

wherein

said control means is operable in response to said VECTOR BYTE AVAILABLE signal for fetching an error correction vector from said queue means;

computing a location in said buffer means of a byte having an error in accordance with the data provided in said error correction vector;

fetching the byte from said location in said buffer means for correction of the error; and

restoring the corrected byte to said location in said buffer means.

27. An error processor as recited in claim 25, wherein said error processor further comprises:

means for indicating a status of a correction operation, for identifying an error location, and for determining an error value;

means for including said status of a correction operation, said error location, and said error value in said error correction vector; and

means for generating a dummy vector when said status of a correction operation indicates a terminating status,

thereby to provide to said external communications controller in the dummy vector an indication of uncorrectable error status error occurs.

28. An error processor as recited in claim 25 further comprising

status indicating means for including in said error correction vectors a status indicator identifying a status of a correction operation.

29. An error processor as recited in claim 25, further comprising

dummy vector generating means for generating a predetermined dummy error value in an error correction vector when said status indicator thereof identifies an uncorrectable error,

thereby providing to said external control means an indication of uncorrectable error status when an uncorrectable error occurs in a block of received data.