Tom Kelliher, CS 240
Apr. 6, 2012
Exam on 4/13, covering 4.1-5.4, including material covered in class on addition.
Flip-Flops and waveforms.
Sequential circuit design.
Analysis = reverse engineering.
One doesn't ordinarily do this, but doing so will help with sequential circuit design.
Consider the following sequential circuit:
What does it do -- high level?
What happens if we use !Q as the input to the NEXOR rather than Q?
Mealy (this circuit) vs. Moore machines.
What are the equations for
D (input equation)?
Do these differ that much from anything we've already seen?
State tables are similar to truth tables, with two additions:
|Present State||I||Next State||O|
Conveys same information as state table, in a visual form.
State diagram for our example (Mealy):
How do I read this?
Moore machine example:
Determine input and output equations, state table, and state diagram for this circuit:
Is this Mealy or Moore?