Some how perl doesn't allow me to unpack like this (look at H2 H2 H16 H2 A2 ...) ... Any idea how this could be done?

I showed you how. What you're dealing is a text-strings, so if you want bytes, you have to pack them. First pack them to get bytes ( pack 'H*' ) then pack them to get what you're really after ( C An unsigned char (octet) value. ) .....

Commands

perl -le " print unpack q{H*}, q{Y} "
perl -le " print pack q{H*}, q{59} "
perl -le " print ord q{Y}
perl -le " print  pack q{H*}, q{59} "
perl -le " print  unpack q{C}, pack q{H*}, q{59} "
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Session

$ perl -le " print unpack q{H*}, q{Y} "
59

$ perl -le " print pack q{H*}, q{59} "
Y

$ perl -le " print ord q{Y}
89

$ perl -le " print  pack q{H*}, q{59} "
Y

$ perl -le " print  unpack q{C}, pack q{H*}, q{59} "
89
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Y encoded as hex is 59

The numeric value ( ord ) of Y is 89

The C An unsigned char (octet) value, 8-bits, 1-byte of Y is 89