Lab1: Review of Logic Circuit Design

Lab1: Review of Logic Circuit Design
Introduction
The purpose of this lab is to review digital circuit design concepts from the ECE241 Digital Systems course,
including Verilog, finite state machines, and good design practices like control/datapath separation. It will
also introduce you to the SystemVerilog language extensions to Verilog, which helps make your design experience more productive and less error-prone. See the accompanying SystemVerilog Tutorial before attempting
this lab. We will use the Quartus Prime design software with which you became familiar in ECE241. Make
sure you allocate enough time to review tutorials on how to use the software.
Part I
You will design a “guess the number” game and simulate the game using Modelsim: the circuit chooses
a random 8-bit number, and the player needs to guess it. The player enters their guess and uses “enter”
signal to confirm. The game, then tells the player whether their guess is under, over, or equal to the correct
value. In the initial version of the game, the player has unlimited tries and the game stops responding when
the number is guessed correctly. Random number generation is achieved by simply incrementing a counter
continuously until the user provides the first “enter” signal. The number at which the counter stops counting
might as well be random.
Figure 1 is a block diagram of the overall system. For Part 1, the source code is provided to you in the
starter kit, and you will only need to modify the control module. Another purpose of this first lab is to
(re)familiarize you with good hardware design practices, which include good use of module hierarchy and the
naming and purpose of signals. To make the grading process simpler, the actual number that the user needs
to guess is outputted, but this should not be the case for designing the game in reality.
Figure 1: Top-level block diagram of the guess-the-number game
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ECE342: Computer Hardware Lab1: Review of Logic Circuit Design
Note that game contains a separate control and datapath module, which will be discussed below.
actual
en
areset
D Q
+1
<
==
>
8 8 under
equal
clk over
inc_actual
reset
guess 8
Figure 2: Game datapath
Figure 2 shows the datapath module for the first version of the game. Your control logic should initially
keep the inc actual signal high until the user enters their first guess. This will have the 8-bit actual register
land on an effectively-random value, and it should stay constant throughout the rest of the game.
The control module is a finite state machine responsible for implementing the game logic. The file
provided in the starter kit is a bare template to remind you of the generic structure of every FSM you
will make, with the necessary input and output signals already declared. You will need to add states and
functionality to make the game work.
Part II
Modify the game such that the player only gets a maximum of 7 attempts to guess the number. The remaining
number of tries should be an output of the game as shown in Figure 3. The game ends when the player
either runs out of attempts, or guesses the number correctly, at which point the game stops responding and
must be reset. These new game features will require you to understand and modify the control, datapath,
and top-level modules.
Figure 3: Part 2 top module declaration
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ECE342: Computer Hardware Lab1: Review of Logic Circuit Design
Instructions
Preparation
• Re-familiarize yourself with the Quartus Prime software by reading the Quartus Prime Introduction
Using Verilog Designs document, as well as the SystemVerilog Tutorial.
• Download the starter kit for this lab. Using lab1.sv as the template for part1 and part2
• Complete the provided SystemVerilog code to implement Part I. Name the finished code part1.sv
• Enhance the code for Part I to implement Part II. Name the finished code part2.sv
In-Lab
Go through the provided tester for both part1.sv and part2.sv to make sure that your code is able to be
recognized by the automarker
Submission
Your should submit part1.sv and part2.sv
Frequently Asked Questions
In this section, questions from previous years have been collected and answered. Please check here first before
posting a question on Quercus.
Q1: Does the game need to be reset after ‘winning’ to continue playing?
A1: Yes, as it is designed now the game needs to be reset after winning to play another round. This was
done for ease of implementation only.
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