Signal boosting (For me, Eric's post landed in the naughty corner) On 16 November 2016 at 00:19, Eric Smith <space...@gmail.com> wrote:
> Has anyone determined what 48-bit and 56-bit ECC polynomials are used by > the National Semiconductor hard disk controllers? The DP8496/97 allows > choice of hard-wired 16-bit CRC, or 32-bit, 48-bit, or 56-bit ECC. The > 32-bit ECC is a common polynomial known as the Glover polynomial, and it's > the same one used by WD and others. However, National was apparently > extremely proud of the 48-bit and 56-bit polynomials they chose, and the > data sheets say that they require a license agreement with National. > > The more common DP8466 supports 32-bit 48-bit, but allows the user to > configure the polynomial. The data sheet states that National's 48-bit > polynomial is available under license. > > WD wasn't as proud of their 56-bit polynomial; it's given in the WD42C22 > data sheet. It doesn't seem to match National Semicondutor's 56-bit > polynomial. >