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Codiode/Problems/Sequential Logic

Handshake Protocol Timing Analysis

HardLogic CircuitTiming Diagram

A four-phase handshake coordinates data transfer between two asynchronous clock domains.

Five signals are shown: CLK_A (source clock), CLK_B (destination clock), START (input pulse), REQ (source output, initially 0), and ACK (destination output, initially 0).

REQ updates on every LOW-to-HIGH transition of CLK_A: it is set to 1 if START is 1 and ACK is 0, it is set to 0 if ACK is 1, and otherwise holds its current value. ACK updates on every LOW-to-HIGH transition of CLK_B to match the current value of REQ.

Trace REQ and ACK across all 16 time steps.

Constraints

  • REQ only changes state exactly on the rising edges of CLK_A.
  • ACK only changes state exactly on the rising edges of CLK_B.
  • A signal asserted in one domain is not recognized by the other domain until its next rising clock edge.

Topics

clock-domainssynchronizationhandshaking

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Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.

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