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Codiode/Problems/Sequential Logic

Blocking Assignment Race Condition

MediumLogic CircuitDebug

A two-stage pipeline synchronizer passes data between interconnected modules on the rising clock edge. Assume all registers initialize to 0.

Expected behavior:

| Cycle | D | Q1 | Q2 | |-------|-----|------|------| | 1 | 1 | 1 | 0 | | 2 | 0 | 0 | 1 | | 3 | 1 | 1 | 0 |

Simulation shows Q2 = 1 during cycle 1 when D = 1. The pipeline stage is being bypassed and the outputs are non-deterministic across different simulators. Inspect the circuit and correct the fault.

Constraints

  • Use non-blocking assignments for sequential logic.
  • Do not alter the module interface or port names.

Topics

sequentialdebuggingverilograce-condition

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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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