stella/src/emucore/CompuMate.hxx

//============================================================================
//
//   SSSS    tt          lll  lll       
//  SS  SS   tt           ll   ll        
//  SS     tttttt  eeee   ll   ll   aaaa 
//   SSSS    tt   ee  ee  ll   ll      aa
//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
//  SS  SS   tt   ee      ll   ll  aa  aa
//   SSSS     ttt  eeeee llll llll  aaaaa
//
// Copyright (c) 1995-2012 by Bradford W. Mott, Stephen Anthony
// and the Stella Team
//
// See the file "License.txt" for information on usage and redistribution of
// this file, and for a DISCLAIMER OF ALL WARRANTIES.
//
// $Id$
//============================================================================

#ifndef COMPUMATE_HXX
#define COMPUMATE_HXX

#include "bspf.hxx"
#include "CartCM.hxx"
#include "Control.hxx"
#include "Event.hxx"

/**
  Handler for SpectraVideo CompuMate bankswitched games.

  The specifics of the CompuMate format can be found in both the Cart side
  (CartCM) and the Controller side (CMControl).  The CompuMate device is
  unique for the 2600 in that it requires close co-operation between the
  cartridge and the left and right controllers.

  This class acts as a 'parent' for cartridge and both the left and right
  CMControl's, taking care of their creation and communication between them.

  @author  Stephen Anthony
  @version $Id$
*/
class CompuMate
{
  public:
    /**
      Create a new CompuMate handler for both left and right ports.
      Note that this class creates CMControl controllers for both ports,
      but does not take responsibility for their deletion.

      @param cart   The CompuMate cartridge
      @param event  The event object to use for events
      @param system The system using this controller
    */
    CompuMate(CartridgeCM& cart, const Event& event, const System& system);

    /**
      Destructor
      Controllers are deleted outside this class
    */
    virtual ~CompuMate() { }

    /**
      Return the left and right CompuMate controllers
    */
    Controller* leftController() { return (Controller*) myLeftController; }
    Controller* rightController() { return (Controller*) myRightController; }

  private:
    /**
      Called by the controller(s) when all pins have been written
      This method keeps track of consecutive calls, and only updates once
    */
    void update();

    // The actual CompuMate controller
    // More information about these scheme can be found in CartCM.hxx
    class CMControl : public Controller
    {
      public:
        /**
          Create a new CMControl controller plugged into the specified jack

          @param handler  Class which coordinates between left & right controllers
          @param jack     The jack the controller is plugged into
          @param event    The event object to use for events
          @param system   The system using this controller
        */
        CMControl(class CompuMate& handler, Controller::Jack jack, const Event& event,
                  const System& system)
          : Controller(jack, event, system, Controller::CompuMate),
            myHandler(handler)
        {
          if(myJack == Left)
          {
            myAnalogPinValue[Five] = minimumResistance;
            myAnalogPinValue[Nine] = maximumResistance;
          }
          else
          {
            myAnalogPinValue[Five] = maximumResistance;
            myAnalogPinValue[Nine] = minimumResistance;
          }
        }

        /**
          Destructor
        */
        virtual ~CMControl() { }

      public:
        /**
          Called after *all* digital pins have been written on Port A.
        */
        void controlWrite() { myHandler.update(); }

        /**
          Update the entire digital and analog pin state according to the
          events currently set.
        */
        void update() { }

      private:
        class CompuMate& myHandler;
    };

  private:
    // Cart, Event and System objects
    CartridgeCM& myCart;
    const Event& myEvent;
    const System& mySystem;

    // Left and right controllers
    CMControl *myLeftController, *myRightController;

    // System cycle at which the update() method is called
    // Multiple calls at the same cycle should be ignored
    uInt32 myCycleAtLastUpdate;

    // Column currently active
    uInt8 myColumn;
};

#endif