Somehow, character code point numbers are always easier for me to grok (and look up on code charts) when shown in hex; also, it can help to put in a "safe" placeholder for the non-printable ones -- otherwise, they can sometimes make the display somewhat confusing:

for (split //, $str) {
    printf( "%s: %02x\n", (/[[:print:]]/) ? $_:".", ord());
}
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