DigitalInput.hpp

/***************************************************************************
  tag: Peter Soetens  Mon Jan 19 14:11:20 CET 2004  DigitalInput.hpp

                        DigitalInput.hpp -  description
                           -------------------
    begin                : Mon January 19 2004
    copyright            : (C) 2004 Peter Soetens
    email                : peter.soetens@mech.kuleuven.ac.be

 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
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 *   version 2 of the License.                                             *
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 ***************************************************************************/

#ifndef DIGITALINPUT_HPP
#define DIGITALINPUT_HPP

#include "DigitalInInterface.hpp"

namespace RTT
{ namespace dev {

    class RTT_API DigitalInput
    {
    public:
        DigitalInput( DigitalInInterface* dig_in, unsigned int bit_nr, bool invert = false )
            :board(dig_in), bitnumber(bit_nr) , minvert(invert), mvalue(invert)
        {
        }

        DigitalInput( const bool& value, bool invert = false )
            :board(0), bitnumber(0), minvert(invert), mvalue(value)
        {
        }

        ~DigitalInput() {};

        bool isOn() const
        {
            // Q: who knew that != is logical xor ?
            return board ? minvert != board->isOn(bitnumber) : minvert != mvalue;
        }

    private:
        DigitalInInterface *board;
        int bitnumber;
        bool minvert;
        const bool& mvalue;
    };
}}

#endif // DIGITALINPUT_HPP