Here are two little abstraction I made, one to communicate with an Arduino an another to concatenate a list. Both require Zexy. Arduino.pd also requires comport and the included text file "ascii.txt". Arduino.pd is a preliminary exampe and will be further developped.
http://interactivite.danslchamp.org/fichiers/arduino_pd.zip and http://mrtof.danslchamp.org/pd/list-concat.zip
Tom