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Codiode/Problems/Sequential Logic

SR NOR Latch: Missing Cross-Coupling Wire Debug

MediumLogic CircuitDebug

An SR NOR latch provides fundamental 1-bit memory storage for sequential state machines.

Expected behavior:

| S | R | Q(t-1) | Q(t) | Q_bar(t) | |-----|-----|----------|--------|------------| | 0 | 0 | 0 | 0 | 1 | | 0 | 0 | 1 | 1 | 0 | | 0 | 1 | X | 0 | 1 | | 1 | 0 | X | 1 | 0 |

Simulation shows that driving S=1 and R=0 correctly sets Q=1. However, when transitioning to the hold state S=0 and R=0, Q immediately falls to 0. The circuit fails to hold its state and acts strictly as combinational logic. Inspect the circuit and correct the fault.

Constraints

  • The circuit must use exactly two NOR gates.
  • The fix must rely entirely on structural routing without adding new logic components.

Topics

debuglatchessequential-logic

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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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