use constant {
    NAME => 0,
    ONBYTE => 1,
    TWOBYTE => 2,
    FOURBYTE => 3,
    TWOBYTE2 => 4,
    TRAILING => 5,
};

my @fields = unpack( "Z16 C1 C2 C4 C1 x400 C*", $data ); 

print $fields[ NAME ];
print $fields[ FOURBYTE ];
print for @fields[ TRAILING .. $#fields ];

##</code><code>##

my @fields = unpack( "Z16 C S L C x400 C*", $data );