$re = '/(.+?CS.{2})/i';
$str = 'HLI6Ch60000Ch500C0Ch46400Ch30000Ch21888Ch10E79CS07LCU3Ch37880Ch27800Ch16480CS8CA00000000000000000000';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php