As an example, the string "0x0102" should become two bytes where the MSB byte is 0x01 and LSB byte is 0x02

$string =~ '0x0102';
$output = hex($string);
print($output);  # 258 (0x0102)
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Or did you want "\x01\x02":

$string =~ '0x0102';
$output = pack('H*', substr($string, 2));
print($output);  # "\x01\x02"
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