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Codiode/Problems/Sequential Logic

PISO: Back-to-Back Loading Without Gaps

HardLogic CircuitTiming Diagram

A positive-edge-triggered 4-bit Parallel-In Serial-Out (PISO) shift register captures the parallel data D[3:0] when LOAD is HIGH, and shifts the bits left to output the MSB to SOUT when LOAD is LOW.

Six input signals are provided: CLK (clock, period 2), LOAD (control input), and D3 through D0 (parallel data inputs).

Trace the serial output SOUT across all 16 time steps.

Constraints

  • The shift register state and output only transition on the LOW-to-HIGH edge of CLK.
  • The output SOUT always reflects the current value of the most significant bit (MSB) of the internal register.
  • Assume the initial state of the shift register is all zeros.

Topics

Shift RegistersSPIPISO

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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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