Technical Specification: Universal Keyboard Ghosting and Rollover Utility

Overview

A comprehensive, browser-based diagnostic utility designed to visualize physical keyboard hardware performance. It detects ghosting, measures rollover capabilities, and provides real-time latency feedback for mechanical, membrane, and laptop keyboards.

User Interface Design

• Visual Style: Minimalist dark-mode interface. Background color #121212, text colors #E0E0E0 (primary) and #00E676 (active state).
• Key Layouts: Dynamic rendering of standard ANSI and ISO keyboard layouts (Full-size, Tenkeyless, 60%).
• Responsive Structure: Flexbox-based container that adjusts key size relative to screen width.

Core Interactive Features

1. Real-time Key State Mapping:
   • Each key is a visual tile.
   • States: Idle (Gray), Pressed (Lime Green), Ghosted/Error (Warning Red).
2. Simultaneous Key Counter (NKRO Tracker):
   • A prominent header display showing the current number of keys held down.
   • Historical "Max Rollover" counter to track the keyboard's peak performance during a session.
3. Ghosting Detection Algorithm:
   • System compares hardware interrupt events against expected keyboard matrix patterns to flag ghosting (hardware inability to register specific combinations).
4. Input Duration & Latency Logger:
   • A secondary panel that lists every key press with a timestamp, recording how long the key was held, enabling users to check for "chattering" (double-input issues).
5. Keyboard Heatmap Mode:
   • A toggle that overlays a color gradient based on frequency of use (Red for high frequency, Blue for low).
6. Session Logging:
   • Ability to export key press logs as a JSON or CSV file for debugging purposes.

Technical Implementation

• Framework: Vanilla JavaScript (ES6+) for zero-latency event handling; HTML5/CSS3 for layout.
• Event Handling: Utilizes window.addEventListener('keydown') and window.addEventListener('keyup').
• Input Sanitization: Intercepts preventDefault() on browser shortcut keys (like Ctrl+N or Ctrl+W) while the app is active to allow full testing.
• Storage: Use localStorage to save user preferences like layout choice (ANSI vs. ISO) and dark/light mode.

Accessibility & SEO

• ARIA Compliance: All keys are labeled for screen readers.
• Keyboard Control: The app provides a specific 'Focus Mode' where it traps inputs to ensure the browser doesn't interpret navigation keys while testing.
• SEO Focus: Heavy use of descriptive meta tags and semantic HTML5 headers to rank for long-tail search queries related to keyboard hardware troubleshooting.