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Please use code tags for your code snippets.

Is the above statement correct ????

That depends on what you want $clock to contain. If you want it to simply be the string FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF05, then the following should be sufficient:

$clock = 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF05';
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If you try to print out the value of $clock in your code, you might get:

use warnings;
use strict;

my $clock = pack('H34','FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF05');
print "clock:$clock:\n";
for (split //, $clock) {
    print "$_:", ord $_, ":\n";
}
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outputs (unprintable characters):

clock:\uffff\uffff\uffff\uffff\uffff\uffff\uffff\uffff\uffff\uffff\uff
+ff\uffff\uffff\uffff\uffff\uffff:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
\uffff:255:
:5:
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Take a look at pack.

Update: By the way, a more compact way to assign a value to $clock uses the "repetition operator" (see perlop). These 2 lines are equivalent:

$clock = 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF05';
$clock = 'F' x 32 . '05';
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