{"id":31394,"date":"2025-04-28T07:29:02","date_gmt":"2025-04-28T14:29:02","guid":{"rendered":"https:\/\/digilent.com\/blog\/?p=31394"},"modified":"2025-04-28T07:29:02","modified_gmt":"2025-04-28T14:29:02","slug":"learn-state-machines-counters-with-the-basys-3-stopwatch-challenge","status":"publish","type":"post","link":"https:\/\/digilent.com\/blog\/learn-state-machines-counters-with-the-basys-3-stopwatch-challenge\/","title":{"rendered":"Learn State Machines & Counters with the Basys 3 Stopwatch Challenge"},"content":{"rendered":"

Ready to put your digital logic knowledge to the test? We’re excited to share a project that brings fundamental concepts like state machines and counters to life using the popular Basys 3 FPGA development board<\/a>.<\/span>\u00a0<\/span><\/p>\n

This isn’t just about theoretical learning \u2013 it’s about hands-on interaction. Imagine this: you press a button to start a timer displayed on the Basys 3’s 7-segment display. Then, with precise timing, you try to stop it at the exact moment a visual cue \u2013 the Basys 3’s LEDs filling up \u2013 indicates the target.<\/span>\u00a0<\/span><\/p>\n

This project is a good example of the kind of practical exercises students in digital logic courses can undertake. By working through this “Stopwatch Challenge,” learners can gain a deeper understanding of:<\/span>\u00a0<\/span><\/p>\n

State Machines:<\/span><\/b> See how different states control the flow of the game.<\/span>\u00a0<\/span><\/p>\n

Counters:<\/span><\/b> Observe how digital counters track time.<\/span>\u00a0<\/span><\/p>\n

Hardware Description Languages (HDLs):<\/span><\/b> Understand how Verilog is used to implement these core hardware building blocks.<\/span>\u00a0<\/span><\/p>\n

Let\u2019s break it down into steps:\u00a0<\/strong><\/h4>\n
    \n
  1. Design a counter and use it to blink an LED ten times a second.<\/span>\u00a0<\/span><\/li>\n
  2. Design a basic state machine to enable and disable the blinking LED based on button presses.<\/span>\u00a0<\/span><\/li>\n
  3. For bonus points, debounce your buttons.<\/span>\u00a0<\/span><\/li>\n
  4. Modify your counter to count up or down, selected based on an input. Decode this counter and use it to\u00a0drive the Basys\u2019 LEDs.<\/span>\u00a0<\/span><\/li>\n
  5. Design a binary-coded decimal counter.<\/span>\u00a0<\/span><\/li>\n
  6. Design a seven-segment display controller and use it to display decimal numbers.<\/span>\u00a0<\/span><\/li>\n
  7. Modify your state machine to pull together these disparate parts into a game \u2013 enable the decimal counter when the game is started, pick success and fail states based on the state of the up\/down counter when buttons are pressed, and clear counters (or not!) based on success\/fail status.<\/span>\u00a0<\/span><\/li>\n<\/ol>\n

    \"\"<\/p>\n

    Here’s what you’ll need:<\/span><\/b>\u00a0<\/span><\/h4>\n