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Codiode/Problems/Combinational Logic

Debug a Full Adder Where Sum and Carry Outputs Are Swapped at the Output Pins

MediumLogic CircuitDebug

A full adder computes the arithmetic sum of three 1-bit inputs (A, B, and Cin), producing a 1-bit Sum and a 1-bit carry-out (Cout).

Expected behavior:

| A | B | Cin | Sum | Cout | |-----|-----|-------|-------|--------| | 0 | 0 | 0 | 0 | 0 | | 0 | 0 | 1 | 1 | 0 | | 0 | 1 | 0 | 1 | 0 | | 0 | 1 | 1 | 0 | 1 | | 1 | 0 | 0 | 1 | 0 | | 1 | 0 | 1 | 0 | 1 | | 1 | 1 | 0 | 0 | 1 | | 1 | 1 | 1 | 1 | 1 |

Simulation shows Sum = 0 and Cout = 1 for inputs A=1, B=0, Cin=0. The outputs do not match the expected arithmetic result. Inspect the circuit and correct the fault.

Constraints

  • Do not change the internal logic gates.
  • Ensure the final output matches standard full adder behavior.

Topics

AdderDebugWiring

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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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