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fpga-debugging

Testing & Quality
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On-chip debugging skill with ILA, VIO, and related FPGA debug tools

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How to use this skill

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  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/a5c-ai/babysitter/blob/HEAD/library/specializations/fpga-programming/skills/fpga-debugging/SKILL.md

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

FPGA Debugging Skill

Overview

Expert skill for on-chip debugging using Integrated Logic Analyzer (ILA), Virtual I/O (VIO), and related debug infrastructure for FPGA designs.

Capabilities

  • Insert Integrated Logic Analyzer (ILA) probes
  • Configure trigger conditions and capture depth
  • Design Virtual I/O (VIO) debug interfaces
  • Analyze captured waveforms
  • Use ChipScope/SignalTap for debugging
  • Debug timing and functional issues in hardware
  • Remove debug logic for production builds
  • Configure JTAG and debug hub

Target Processes

  • fpga-on-chip-debugging.js
  • functional-simulation.js
  • design-for-testability.js

Usage Guidelines

ILA Insertion

  • Identify critical signals to probe
  • Consider capture depth vs. resource usage
  • Group related signals in single ILA
  • Use mark_debug attribute for HDL signals
  • Configure appropriate data and trigger widths

Trigger Configuration

  • Use basic triggers for simple conditions
  • Apply advanced triggers for complex patterns
  • Combine triggers with AND/OR logic
  • Configure trigger position in capture window
  • Use storage qualification for efficient capture

VIO Usage

  • Create debug control interfaces
  • Inject test patterns dynamically
  • Override internal signals
  • Monitor status in real-time
  • Useful for bring-up and characterization

Debug Infrastructure

  • Connect debug hub to JTAG
  • Configure clock domain for debug logic
  • Plan for multiple ILA instances
  • Consider debug access port routing
  • Document debug signal mapping

Production Considerations

  • Use ifdef guards for debug logic
  • Create debug and release build flows
  • Minimize debug impact on timing
  • Remove debug before final release
  • Maintain debug build configurations

Dependencies

  • Debug tool CLI (hw_server, etc.)
  • JTAG connectivity
  • Vendor debug IP knowledge