I like it, but i do have a couple of suggestions:

First, please pick an indentation style and stick with it. Check out perltidy.

Second, you are using foreach where you should be using map, and you are using map where you should be using foreach (or for). Try this instead: 
sub convert_hex {
   my @charconv = map { pack "H*", $_ } split(/\s/, $hexval->get);

   $charval->delete(0, 'end');
   $charval->insert(0, $_) for reverse @charconv;
}

sub convert_char {
   my @hexconv = map { unpack "H*", $_ } split(//, $charval->get);

   $hexval->delete(0, 'end');
   $hexval->insert(0, $_) for reverse @hexconv;
}

[download]
Use map when you want to transform one list (array) into another - don't use it in void context, use for (or foreach) instead. Other then that, looks good to me. :)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: Perl/TK hex2char - char2hex convertor by jeffa
in thread Perl/TK hex2char - char2hex convertor by semio

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