From what I can gather, this isn't the sort of beast you want to learn if you don't know how to program in C/C++. C and C++ take years to learn well enough to do major programming. Not that I'm calling this major, but I would say that at least a few months of reading up would be required. Unless there are already header files, etc. for OBD that someone has already produced that you can link into your code and all that would be required is dumping to the screen. Which can be doine using bitblit'ing or echoing from the terminal.