jrubins:
Having multiple machines running at once could be very useful though.
It's just more work for the small Arduino processor to do.
If you are eventually going to send the Mash codes from a PC program you can have the human-readable stuff on the PC but just send short codes to the Arduino. However if using codes with 3, 4 or 6 characters makes the Arduino code easier to understand I would happily use them. A key factor is that the codes all be the same length to make reception by the Arduino easier.
...R