On 31/01/11 14:25, alan.b.pearce@stfc.ac.uk wrote:
>> I'm working on implementing the 4-byte (32-bit) ECC code Western Digital
>> used on the WD2010 Winchester HDD Controller IC. This appears to be an
>> implementation of the ECC scheme explained in section 7.6 of National
>> Semiconductor's "Disk Interface Design Guide and User's Manual" (appnote
>> AN-413).
>
> I believe this is the code used on all 5 1/4" and smaller HD units since =
the original 5MB ones.

Similar. The early Seagate ST506 drives used a straight CRC16 with no=20
error correction.

>> Does anyone recognise this polynomial?
>>         x^32 + x^28 + x^26 + x^19 + x^17 + x^10 + x^6 + x^2 + 1
>> aka.  x^32 + x^28 + x^26 + x^19 + x^17 + x^10 + x^6 + x^2 + x^0
>> or:   0x140A0443
>
> I think you will find it is a Reed-Solomon code http://en.wikipedia.org/w=
iki/Reed-Solomon_error_correction

It doesn't look that way to me.. certainly not from the datasheets, anyway.

I've spent all day hacking away on an implementation of the=20
shift-register ECC engine on the WD1100, but it isn't matching up, no=20
matter what I do...

UGH.

--=20
Phil.
piclist@philpem.me.uk
http://www.philpem.me.uk/
--=20
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