when using serial command system I have tried to use a protocol that uses ascii characters either in a tradition command format or as status bits condensed into bytes that can be diplayed by settin a vt100 to show control chars. Where a protocol has been defined that cannot be displayed by a terminal I have used a modified version initally to get the system working then switched to the correct protocol. I used this route in the early days of DMX 512 to get a lighting control system rumnning