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Codiode/Problems/Sequential Logic

SR NOR Latch: Q_bar Polarity and Active Level

MediumLogic CircuitBuild

Alarm systems and power controllers use cross-coupled logic to retain state after a trigger event is removed. The SR NOR latch provides this fundamental storage behavior: two inputs command the state, while two outputs provide the stored value and its complement.

A strict inverse relationship between the outputs is not guaranteed. During the forbidden state where both inputs are asserted, both outputs are driven LOW. Downstream logic must use the true Q output for status indicators to avoid false positives during this state.

| S | R | Q | Q_bar | |-----|-----|-----|---------| | 0 | 0 | Hold| Hold | | 0 | 1 | 0 | 1 | | 1 | 0 | 1 | 0 | | 1 | 1 | 0 | 0 |

Constraints

  • Implement the circuit using exactly two NOR gates.
  • Do not use NOT gates to derive Q_bar from Q or vice versa.

Topics

LatchesSequential LogicSR LatchNOR Gates

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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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