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Clematrics

Is it possible to bind the output of a sub-module to two different output ports?

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I am trying to make a circuit which computes the carries for an addition.
In this piece of code, I would like to connect the output port rOut of the submodule pg to two output ports (rOut and carries[0]) of the parent module, so both get the same value.

template<>
struct Carries<1> : ::sc_core::sc_module {
    sc_vector<sc_in<bool>> a, b;
    sc_in<bool> rIn;
    sc_out<bool> p, g, rOut;
    sc_vector<sc_out<bool>> carries;

    CarryPropGen pg {"PG"};

    SC_CTOR(Carries)
        :   a {"vectA", 1}, b {"vectB", 1},
            rIn {"rIn"},
            p {"p"}, g {"g"}, rOut {"rOut"},
            carries {"vectCarries", 1} {
        pg.a(a[0]);
        pg.b(b[0]);
        pg.r(rIn);

        pg.p(p);
        pg.g(g);
        pg.rOut(rOut);			// What I would like to do.
        pg.rOut(carries[0]);		// 
    }
};

However, I get the error (E109) complete binding failed: 2 binds exceeds maximum of 1 allowed: port 'Carries.PG.port_5' (sc_out). I also tried with a signal, with and without the writer policy SC_MANY_WRITER, as it was suggested by someone on a forum, but it didn't work either.

I am new to SystemC and while I understand the error, I don't really understand why this can't work and how to do it differently. So, is there a way to bind one sub-module output to multiple sc_out of the parent module, and how?

Edited by Clematrics
The text size was way too high (I still can't edit the text size of the code)

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You need to connect the output port to a signal and attach a method to the signal driving the multiple output ports. So something like this:

template<>
struct Carries<1> : ::sc_core::sc_module {
    sc_vector<sc_in<bool>> a, b;
    sc_in<bool> rIn;
    sc_out<bool> p, g, rOut;
    sc_vector<sc_out<bool>> carries;

    CarryPropGen pg {"PG"};

    SC_CTOR(Carries)
        :   a {"vectA", 1}, b {"vectB", 1},
            rIn {"rIn"},
            p {"p"}, g {"g"}, rOut {"rOut"},
            carries {"vectCarries", 1} {
        pg.a(a[0]);
        pg.b(b[0]);
        pg.r(rIn);

        pg.p(p);
        pg.g(g);
        pg.rOut(rOutS);			// What I would like to do.
        SC_METHOD(propagate);
		sensitive<<rOutS.value_changed();
    }
    sc_core::sc_signal<bool> rOutS;
    void propagate(){
      rOut.write(rOutS.read());
      carries[0].write(rOutS.read();
    }
};

BR

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