This is really basic stuff everybody involved in electronics should know about.
Dave would have his work cut out to cover it all.
Get a copy of the old yellow TI 74 logic databook (also available as PDF file!), that covers most of it.
Learn how to use truth tables - I find them most helpful.
Get a couple of old 74xx chips and a breadboard and play around with it. I've always preferred learning by doing, we used to do that at school in technology classes.
I don't know if they still do it today, probably all microcontrollers these days. I still think that basic knowledge of logic gates, boolean algebra and how it all works in real hardware is absolutely essential.