I'm not sure why you crossed out your first answer. It is correct; the way to change between big and little endian packed IEEE floats is to use reverse: 
    $ perl -le 'print unpack "H*", reverse pack "f", 440'
    43dc0000

    $ perl -le 'print unpack "H*",         pack "f", 440'
    0000dc43

[download]

--
John.

In reply to Re^2: Stumped by a pack/unpack problem by jmcnamara
in thread Stumped by a pack/unpack problem by crenz

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