Creating a Reaction Time Game on the Basys 3 Board

The Basys 3 board, a popular development platform among FPGA enthusiasts, provides an ideal environment for implementing a reaction time game. In the realm of digital design and embedded systems, practical assignments provide invaluable experience, bridging the gap between theory and hands-on application. One such assignment that frequently appears in coursework is the development of a reaction time game using FPGA (Field-Programmable Gate Array) boards, such as the Basys 3. These programming assignments challenge students to leverage their understanding of hardware design, timing, and digital logic to create a functional and engaging game. In this comprehensive guide, we will delve into the steps necessary to successfully complete your VHDL assignments, providing a detailed walkthrough from understanding the requirements to finalizing your submission.

Design Overview and Requirements

Designing a reaction time game on the Basys 3 board involves creating a sequence of LED patterns that serve as a "Start" signal for the player. The player's reaction time is then displayed on the 7-segment display in milliseconds. The game must also keep track of the highest score (i.e., the shortest reaction time) and include some creative features to make it more engaging. Below are the specific design requirements and the breakdown of the necessary functionalities.

Game Initialization and LED Patterns

The game begins by displaying a pattern of LEDs, which acts as the "Start" signal. Players must press a button as quickly as possible after the LEDs light up. The following subsections describe how to implement and manage the LED patterns.

LED Pattern Generation

To create an engaging and challenging experience, the LED pattern should be designed to catch the player's attention and encourage rapid responses. The LED pattern can be a simple sequence or a more complex design, depending on the difficulty level selected by the player.

1. Basic LED Patterns: Implement a simple left-to-right or right-to-left LED chase pattern. This can be achieved using a counter that cycles through the LEDs on the Basys 3 board.
2. Advanced LED Patterns: Create more complex patterns that light up randomly or follow a non-linear sequence. This can be implemented using a pseudo-random number generator to determine which LEDs light up at each step.
3. Pattern Speed and Variation: Adjust the speed of the LED patterns to increase the difficulty level. Slower patterns are easier to react to, while faster patterns provide a greater challenge.

Synchronous Reset and Debouncing

A synchronous reset ensures that all components of the game return to their initial states when the reset button is pressed. This is crucial for maintaining the integrity of the game and providing a consistent starting point for each new round.

1. Implementing a Synchronous Reset: Use a reset signal that is synchronized with the clock signal to reset all game variables and components.
2. Button Debouncing: Debouncing is essential to ensure that the button press is registered accurately without multiple false triggers. Implement a debounce circuit or algorithm to filter out noise and mechanical bounce.
3. Testing and Validation: Create a test bench to simulate button presses and verify that the reset and debounce mechanisms work correctly.

Measuring Reaction Time

The core of the game is measuring how quickly the player reacts to the LED pattern. This involves capturing the time between the LED pattern appearing and the player's button press.

Time Measurement Mechanism

To measure the reaction time accurately, the design needs to count the clock cycles from the moment the LED pattern is displayed until the button is pressed.

1. Clock Counting: Utilize the Basys 3 board's 100MHz clock to count the number of cycles from the start of the LED pattern to the button press. Convert this count into milliseconds for display purposes.
2. Interrupt Handling: Configure an interrupt to detect the button press and stop the clock count, thereby recording the reaction time. Ensure that the interrupt is debounced to avoid false triggers.
3. Display Conversion: Convert the clock count into milliseconds and display it on the 7-segment display. This requires scaling the clock count appropriately and formatting the output for the display.

High Score Tracking

The game should keep track of the lowest reaction time and display it as the high score. If a new high score is achieved, the LEDs should blink to indicate the accomplishment.

1. High Score Logic: Implement logic to compare the current reaction time with the stored high score. If the current time is lower, update the high score.
2. LED Indication: Create a blinking LED pattern to celebrate a new high score. This can be a simple on-off sequence or a more elaborate pattern to add excitement.
3. Persistent High Score Display: Between game rounds, display the high score on the 7-segment display. Ensure that the high score is retained until a new one is achieved.

Adding Creative Features

To make the game more engaging, we can incorporate additional creative features. These features can range from integrating different input methods to enhancing the game's visual and auditory feedback.

USB Control and VGA Display

Integrating USB and VGA capabilities allows for more sophisticated control and output options, enhancing the user experience.

1. USB Control: Use the Basys 3 board's USB interface to allow players to control the game with external devices like keyboards or game controllers. This can be implemented by reading input data from the USB port and translating it into game actions.
2. VGA Display: Display the game output on a monitor using the VGA connection. This provides a larger and more immersive display area compared to the onboard LEDs and 7-segment display. The VGA display can show detailed game statistics, scores, and visual effects.

Implementing Difficulty Settings

Adding difficulty settings via the board's switches allows players to customize the game's challenge level.

1. Difficulty Switches: Use the Basys 3 board's switches to select different difficulty levels. Each switch position can correspond to a different game speed or LED pattern complexity.
2. Dynamic Difficulty Adjustment: Implement a feature that dynamically adjusts the difficulty based on the player's performance. For example, if the player consistently achieves low reaction times, the game can increase the speed of the LED patterns.

Multi-Modal Start Signals

Introducing multi-modal start signals enhances the game's sensory feedback and accessibility.

1. Sound Signals: Use the board's audio capabilities to play a sound when the LED pattern appears. This can provide an additional cue for players and make the game more inclusive for visually impaired users.
2. Vibration Feedback: If the Basys 3 board is connected to a device capable of vibration, such as a motor or a haptic actuator, use it to give tactile feedback when the game starts. This adds another layer of sensory interaction.
3. Visual and Auditory Cues: Combine visual and auditory signals to create a more engaging start sequence. For example, synchronize the LED pattern with a sound effect for a more immersive experience.

Game Mechanics and Test Bench Design

Implementing complex game mechanics and creating a comprehensive test bench are critical for ensuring the game's functionality and robustness.

Multi-Player Mode and Rounds

Introducing multi-player mode and game rounds adds depth and competitiveness to the game.

1. Multi-Player Mode: Allow multiple players to compete by taking turns or by using different buttons for each player. Keep track of each player's reaction time and display the winner at the end of each round.
2. Rounds and Score Tracking: Implement multiple rounds of gameplay and keep track of scores across rounds. This adds a layer of strategy as players try to achieve the best overall reaction time.

Test Bench Development

Creating a test bench for each new or significantly modified file ensures that all functionalities are thoroughly tested.

1. Test Bench for LED Patterns: Simulate different LED patterns and verify that they are displayed correctly. Test the patterns at various speeds and ensure they match the expected behavior.
2. Test Bench for Reaction Time Measurement: Verify that the reaction time is measured accurately by simulating different button press timings. Ensure that the time is displayed correctly in milliseconds.
3. High Score Logic Testing: Test the high score logic by simulating multiple rounds of gameplay. Ensure that the high score is updated correctly and that the LEDs blink when a new high score is achieved.

Block Diagrams and Design Documentation

Creating detailed block diagrams and comprehensive design documentation is essential for planning and verifying the design.

1. Top-Level Block Diagram: Create a top-level block diagram that shows the overall structure of the game, including the main components and their interactions.
2. Component Block Diagrams: Create detailed block diagrams for each major component, such as the LED pattern generator, the reaction time counter, and the high score logic.
3. Design Documentation: Document the design process, including the initial planning, design choices, and testing results. This documentation should explain how each component works and how it integrates into the overall game.

Code Submission and Video Walkthrough

Submitting well-commented code and providing a clear video walkthrough are crucial for demonstrating the functionality and completeness of the game.

Code Submission

The submitted code should be complete, synthesize to a bitstream file, and be ready for deployment on the Basys 3 board.

1. File Completeness: Ensure that all code files, including test benches and constraint files, are included in the submission. The constraint file should map correctly to the Basys 3 board's inputs and outputs.
2. Code Comments and Documentation: Include detailed comments in the code to explain the functionality of each section. Provide explanations for complex logic and describe how the code integrates with the hardware.
3. Bitstream File: Generate a bitstream file from the synthesized code that can be uploaded to the Basys 3 board. Verify that the bitstream file creates a playable game.

Conclusion

Tackling programming assignments can be a complex but rewarding task. By following a structured approach and using the tips and techniques outlined in this guide, you can effectively solve similar assignments and build your skills in both software and hardware development. Remember to plan carefully, implement systematically, and test thoroughly to ensure success in your programming assignments. For further assistance or to get help with your programming assignments, feel free to visit programminghomeworkhelp.com. We offer affordable and expert help to guide you through your programming challenges and ensure you achieve the best results in your assignments.