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Codiode/Problems/Sequential Logic

DFF with Active-Low Asynchronous Reset: Construction

EasyLogic CircuitBuild

Microcontrollers and system-on-chip designs rely on reliable initialization states to prevent erratic behavior at power-up. An asynchronous reset forces the storage element to a known state immediately upon assertion, completely independent of the clock signal.

The circuit must capture the input D on the rising edge of CLK when RST_bar is 1. When RST_bar is 0, the output Q must become 0 instantly, overriding any clock or data activity.

| RST_bar | CLK | D | Q | |-----------|-------|-----|-----| | 0 | X | X | 0 | | 1 | 0 -> 1| 0 | 0 | | 1 | 0 -> 1| 1 | 1 | | 1 | 0 | X | Hold| | 1 | 1 | X | Hold|

Constraints

  • Build the circuit using only basic logic gates.
  • Do not use pre-built flip-flop or latch primitives.
  • Implement an asynchronous reset path that bypasses the clock dependency.

Topics

LatchesSequential LogicFlip-FlopsAsynchronous Reset

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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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