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Codiode/Problems/Sequential Logic

Mealy Output Combinational Loop

HardLogic CircuitDebug

A bus arbiter and requester pair manages shared bus access.

Expected behavior:

| Cycle | Start | Req | Grant | |-------|---------|-------|---------| | 1 | 0 | 0 | 0 | | 2 | 1 | 1 | 0 | | 3 | 0 | 0 | 1 | | 4 | 0 | 0 | 0 |

Simulation halts with a combinational loop error during Cycle 2. The synthesis logs report a zero-delay circular dependency between Req and Grant. Inspect the circuit and correct the fault.

Constraints

  • Ensure the arbiter output is properly registered.
  • Do not alter the requester's combinational logic.
  • Maintain the exact cycle timing shown in the expected behavior table.

Topics

sequential-logicarbitercombinational-loopmealy-machine

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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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