9. XOR Gate Using Basic Gates

How do you plan to solve it?

Take the Boolean equation, break it down in the circuit and directly implement it by instantiating.

// ============================================================
// Basic Gates (given)
// ============================================================
module and_gate(input a, b, output y);
    assign y = a & b;
endmodule

module or_gate(input a, b, output y);
    // write code here for or gate
    assign y = a | b;

endmodule

module not_gate(input a, output y);
    // write code here for not gate
    assign y = ~a;

endmodule

// ============================================================
// XOR Gate
// ============================================================
module xor_gate (
    input  a, b,
    output y
);
    // TODO: declare intermediate wires
    wire and_o_0, and_o_1;
    wire not_o_0, not_o_1;

    // TODO: instantiate required gates
    not_gate DUT0 (.a(a),
                   .y(not_o_0)
                   );

    not_gate DUT1 (.a(b),
                   .y(not_o_1)
                   );

    and_gate DUT2 (.a(a),
                   .b(not_o_1),
                   .y(and_o_0)
                   );

    and_gate DUT3 (.a(b),
                   .b(not_o_0),
                   .y(and_o_1)
                   );

    or_gate DUT4 (.a(and_o_0),
                  .b(and_o_1),
                  .y(y)
                  );

endmodule