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Codiode/Problems/Sequential Logic

SISO: Wrong D-to-Q Wiring Debug

MediumLogic CircuitDebug

A 4-bit Serial-In Serial-Out (SISO) shift register delays an incoming data stream by four clock cycles.

Expected behavior:

Data applied at D_in propagates through four sequential flip-flop stages and appears at Q_out exactly four clock cycles later.

| Clock Edge | D_in (before edge) | Q_out (after edge) | |------------|----------------------|----------------------| | 1 | 1 | 0 | | 2 | 0 | 0 | | 3 | 0 | 0 | | 4 | 0 | 1 | | 5 | 0 | 0 |

Simulation shows that a logic 1 entered at D_in exits at Q_out after 3 cycles instead of 4. The overall latency of the shift register is incorrect. Inspect the circuit and correct the fault.

Constraints

  • Do not add or remove any flip-flops.
  • Only modify the incorrect wire connection.

Topics

shift-registerdebugsiso

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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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