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Codiode/Problems/Sequential Logic

JK Flip-Flop vs SR Forbidden State

MediumLogic CircuitTiming Diagram

A positive-edge-triggered JK flip-flop toggles its output when both inputs are HIGH, whereas a positive-edge-triggered SR flip-flop enters an indeterminate state when both inputs are HIGH. Five signals are shown: CLK (clock, period 2), IN1 (shared J and S input), IN2 (shared K and R input), Q_JK (JK output, initially 0), and Q_SR (SR output, initially 0). Trace Q_JK and Q_SR across all 12 time steps.

Constraints

  • Evaluate input signals only on the LOW-to-HIGH transitions of CLK.
  • Use the character "X" to represent an indeterminate state for any output.
  • Mid-cycle input changes do not affect the output until the next rising clock edge.

Topics

sequential-logictiming-diagramflip-flops

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