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Codiode/Problems/Sequential Logic

Gated SR Latch: Enable Connected to Wrong NAND Input Debug

HardLogic CircuitDebug

A gated SR latch stores a single bit of data and only responds to set and reset inputs when the enable signal is active.

Expected behavior:

| EN | S | R | Q | Q_n | |------|-----|-----|-----|-------| | 1 | 1 | 0 | 1 | 0 | | 1 | 0 | 1 | 0 | 1 | | 1 | 0 | 0 | Latch | Latch | | 0 | 0 | 0 | Latch | Latch | | 0 | 1 | 0 | Latch | Latch | | 0 | 0 | 1 | Latch | Latch |

Simulation shows Q changing state when EN=0. Specifically, when transitioning to inputs S=1 and R=0 while EN=0, the output Q incorrectly becomes 1. The latch fails to hold its state and acts as if the enable signal is completely ignored. Inspect the circuit and correct the fault.

Constraints

  • Do not add or remove any logic gates.
  • Only modify the existing wiring to correct the logic fault.
  • Ensure the circuit does not short an output to another output.

Topics

DebugLatchesSequential LogicSR Latch

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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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