Transcript Introduction to Digital Design Lab Project

Introduction to
Digital Design Lab Project
PC/CP 120
Digital circuits design
Detector
Detector
)))
a
F
b
a
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
F
Project Design Steps
Step 1: Define the problem
– 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.
Project Design Steps
Step 3: Implementation
– 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.
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.
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.
Choose lab topic by next week.
No duplicates
First come, first serve!
Projects can be found on the
CP/PC120 lab page.