Hi,

I need to implemenmt CRC-32 (with custom poly) in Perl.

I have seen that there is a module called digest::crc that does it.

However, when I compare the result to an online calculator, I dont get the same CRC code.

My poly is "101101" (bin) or "2d" (hex)

My data is "1e5"

The online calc is:

https://ghsi.de/CRC/index.php?Polynom=101101&Message=1e5

The result that I get from the calc is "1010" (bin) or "A" (hex)

This is the perl code I used (found somewhere online...):

use strict;
use warnings;
use Digest::CRC;

my $string = 0x01e5;
my $ctx = Digest::CRC->new(type=>"crc32", poly=>0x2D);

$ctx->add($string);

print "CRC for '$string' is 0x" . $ctx->hexdigest . "\n";

[download]

This is the output of this perl:

CRC for '485' is 0x9d0fec86

I'm pretty sure that the online calculator is correct.

Can someone help me understand what is wrong with my Perl code?

Thx!

Guy

In reply to How to use perl digest module to calculate CRC? by guyra

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