Your value comes from a big-endian system, so you'll need 'd>' to decode it:

$n = pack 'H16', '3f0df9673344c570';;

print unpack 'd>', $n;;
5.71713084433029e-005

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You could also do the byte swapping yourself:

$n = pack 'H16', '3f0df9673344c570';;

print unpack 'd', scalar reverse $n;;
5.71713084433029e-005

[download]
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In reply to Re: Converting binary to double precision (big-endian) by BrowserUk
in thread Converting binary to double precision by ahoriuch

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