1. Introduction to Digital Design Lab Project
PC/CP 120

2. Digital circuits design
Detector
Detector a
))) a F F b b
System Switch
Digital Fire alarm system
Combinational circuit:
A digital circuit whose outputs depends solely on the present combination of the circuit inputs’ values.
Turn on alarm (F=1) when smoke sensed (a=1) and system switch is on (b = 1)
F = a AND b
Build using logic gates  AND

3. Project Design Steps Step 1: Define the problem Step 2: Logic design
Describe the problem to be solved by the circuit (i.e. what it is supposed to do). What are the inputs and outputs.
Step 2: Logic design
Capture the function
Create a truth table or equations, whichever is most natural for the given problem, to describe the desired behavior of the combinational logic.
Convert to equations
If you capture the function with a truth table you will need to do this step.
Simplification
Boolean Algebra, Karnaugh Map, ..etc
If any errors appear at any stage, revise earlier phases.

4. Project Design Steps Step 3: Implementation Step 4: Circuit Simulation
Create a circuit corresponding to the output's equation. Use logic gates – AND, OR, NAND, NOR, XOR …etc
Draw a circuit diagram (or diagrams) of the circuit showing all connections and gates to be used.
You will use Altera Quartus II to draw your circuit.
Step 4: Circuit Simulation
Demonstrate that the circuit performs as expected.
Choices made regarding what to simulate.
You will be using Altera Quartus II for the simulation.
If any errors appear at any stage, revise earlier phases.

5. Project Design Steps Step 5: Prototype Test Results
Download your circuit to the CPLD board
Wire the input and output to demo your circuit.
Step 6: Demonstration
Demo your circuit to other groups in the class
Produce a poster showing your project steps .
Poster should contain a brief description of your testing procedure, outlining any significant problems encountered along the way.
Peer-to-Peer evaluation, 3% of project mark.
If any errors appear at any stage, revise earlier phases.

12. Propagation delay
The time required for any signal transition to travel between pins and/or nodes in a device.
The total propagation delay time through a logic circuit is a major consideration.
Propagation delays are additive, so the more gates or inverters between input and output, the greater the propagation delay time.

13. Choose lab topic by next week. No duplicates First come, first serve!
Projects can be found on the CP/PC120 lab page.