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computing 64 bit crc on a 32 bit compiler

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  computing 64 bit crc on a 32 bit compiler BING BANG <bing1351@gmail.com> - 2012-03-14 14:52 -0700
    Re: computing 64 bit crc on a 32 bit compiler Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-03-14 23:13 +0000
    Re: computing 64 bit crc on a 32 bit compiler glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-03-15 00:30 +0000
    Re: computing 64 bit crc on a 32 bit compiler "Bill Davy" <Bill@SynectixLtd.com> - 2012-03-15 17:55 +0000

#14930 — computing 64 bit crc on a 32 bit compiler

Any body know where I might find such code?

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#14931

On Wed, 2012-03-14, BING BANG wrote:
> Any body know where I might find such code?

First read the Wikipedia article for "Cyclic redundancy check". Then
you'll notice there are at least two different 64-bit CRCs in use; you
have to decide which one you want.

/Jorgen

-- 
  // Jorgen Grahn <grahn@  Oo  o.   .     .
\X/     snipabacken.se>   O  o   .

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#14933

BING BANG <bing1351@gmail.com> wrote:
> Any body know where I might find such code?

The only 64 bit CRC polynomial that I know of is very easy to
do on 32 bit machines, as it has no terms in the upper half.

Otherwise, it takes a little work to get the shifts to work right, 
but isn't really all that hard to do.

-- glen

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#14942

"BING BANG" <bing1351@gmail.com> wrote in message 
news:f9ff9705-02ea-433b-a827-85a6e5ba6561@g16g2000yqe.googlegroups.com...
> Any body know where I might find such code?


http://www.tty1.net/pycrc/

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