Hello again... :lol: ....I was wondering if anyone has information about the Class II data systems used on many vehicles.I believe it is the SAE J1850 protocol.I want to know some information about these systems because I like to tinker with my new truck,and I would like to build interfaces like this one...**broken link removed** know that there is ready made units available for this purpose,but I would like to build some just for the fun of it.If someone could point me in the right direction as far as literature on the subject goes,it would be much appreciated,thanks.....