I was thinking of the difference between the Rev 1 and Rev 2 boards, as outlined here-
http://raspi.tv/2013/rpi-gpio-basics-2-how-to-check-what-pi-board-revision-you-have
I’m new enough to the game that all I have are 2b’s, 3b’s, and Zero’s. This stuff is great fun, and Cayenne keeps me from having to futz with too much code, thank goodness.
Looking forward to a full report on what gets built around your RPi’s, and don’t forget the contest, you could win a trip to Mustang country!
Ian