Computer System Architecture: Understanding State Tables/Diagrams

[EEhokie13]

Hey,
My textbook, Computer System Architecture, by M. Morris Mano, describes state tables/diagrams. After reading over them a few times I am still struggling to understand the concept or actually how they work. For example if you have two flip flops, Da and Db with two inputs, x and y, with one output z how would your make the table?

Da = x(not)y + xA
Db = x(not)B + xA
z = B

I do know that the table starts with a present state, which i think means Da? but I get lost from there. Any help will be great. Thank you!

 

[anorlunda]

When you have a stateful object, the previous state is usually shown as an independent input. Therefore you have three inputs, x, y, and previous state.