CDC Protocols & Handshakes

Section goal

Async FIFO architecture, handshake protocols, pulse crossing patterns, and protocol-level verification closure.

How to study this section

1. Start with topic hubs to classify problem shapes.

2. Use mechanism and reports pages to connect risk signals to evidence.

3. Practice debug and worked examples before signoff reviews.

4. Close with checklist and silicon impact before approving fixes or waivers.

Topics

1. async-fifo-cdc/ — Async FIFO CDC

2. handshake-protocols/ — Handshake Protocols Across Domains

3. pulse-synchronizers/ — Pulse Synchronizers

4. protocol-verification/ — CDC Protocol Verification

Related topics

• CDC/RDC course hub

CDC/RDC deep dive

Protocol correctness is the bridge between structural clean and functional safe.

Concept diagram

PROTOCOL FLOW

intent -> transport protocol -> synchronization -> destination acceptance

Metric graph

PROTOCOL ISSUE BURNDOWN

open issues: 20 -> 11 -> 5 -> 0

Reports and artifacts

• FIFO pointer proofs

• req/ack liveness

• pulse miss checks

• protocol assertions

Mini case study

Async FIFO empty/full logic looked correct until gray decode mismatch appeared during reset overlap.

Debug branches

• Pointer sync audit

• formal liveness checks

• reset interaction review

Senior review question

Ask: what evidence proves this risk is closed for silicon, not just tool-clean?