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Codiode/Problems/Sequential Logic

SR NOR Latch: Forbidden State Behavior

MediumLogic CircuitTiming Diagram

An SR latch typically avoids simultaneous input assertion, but in this specific logic model the forbidden state S=1 and R=1 forces both Q and Q_bar HIGH.

Four signals are shown: S (set input), R (reset input), Q (primary output, initially 0) and Q_bar (complement output, initially 1).

Trace Q and Q_bar across all 8 time steps.

Constraints

  • The outputs must reflect the exact rule given for the forbidden state, temporarily violating the complement property.
  • When the forbidden state ends, the outputs must resolve immediately based on the remaining asserted input.

Topics

Combinational LogicLatchesFlip-FlopsForbidden State

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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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