1 //============================================================================
2 //
3 //   SSSS    tt          lll  lll
4 //  SS  SS   tt           ll   ll
5 //  SS     tttttt  eeee   ll   ll   aaaa
6 //   SSSS    tt   ee  ee  ll   ll      aa
7 //      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
8 //  SS  SS   tt   ee      ll   ll  aa  aa
9 //   SSSS     ttt  eeeee llll llll  aaaaa
10 //
11 // Copyright (c) 1995-2021 by Bradford W. Mott, Stephen Anthony
12 // and the Stella Team
13 //
14 // See the file "License.txt" for information on usage and redistribution of
15 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
16 //============================================================================
17 
18 #ifndef MINDLINK_HXX
19 #define MINDLINK_HXX
20 
21 #include "bspf.hxx"
22 #include "Control.hxx"
23 
24 /**
25   The Atari Mindlink was an unreleased video game controller intended for
26   release in 1984.  The Mindlink was unique in that one had to move the
27   muscles in one's head to control the game. These movements would be read by
28   infrared sensors and transferred as movement in the game.  For more
29   information, see the following link:
30 
31     http://www.atarimuseum.com/videogames/consoles/2600/mindlink.html
32 
33   This code was heavily borrowed from z26, and uses conventions defined
34   there.  Specifically, IOPortA is treated as a complete uInt8, whereas
35   the Stella core actually stores this information in boolean arrays
36   addressable by DigitalPin number.
37 
38   @author  Stephen Anthony, Thomas Jentzsch & z26 team
39 */
40 class MindLink : public Controller
41 {
42   public:
43     /**
44       Create a new MindLink controller plugged into the specified jack
45 
46       @param jack   The jack the controller is plugged into
47       @param event  The event object to use for events
48       @param system The system using this controller
49     */
50     MindLink(Jack jack, const Event& event, const System& system);
51     ~MindLink() override = default;
52 
53   public:
54     /**
55       Write the given value to the specified digital pin for this
56       controller.  Writing is only allowed to the pins associated
57       with the PIA.  Therefore you cannot write to pin six.
58 
59       @param pin The pin of the controller jack to write to
60       @param value The value to write to the pin
61     */
write(DigitalPin pin,bool value)62     void write(DigitalPin pin, bool value) override { setPin(pin, value); }
63 
64     /**
65       Called after *all* digital pins have been written on Port A.
66     */
controlWrite(uInt8)67     void controlWrite(uInt8) override { nextMindlinkBit(); }
68 
69     /**
70       Update the entire digital and analog pin state according to the
71       events currently set.
72     */
73     void update() override;
74 
75     /**
76       Returns the name of this controller.
77     */
name() const78     string name() const override { return "MindLink"; }
79 
80     /**
81       Answers whether the controller is intrinsically an analog controller.
82     */
isAnalog() const83     bool isAnalog() const override { return true; }
84 
85     /**
86       Determines how this controller will treat values received from the
87       X/Y axis and left/right buttons of the mouse.  Since not all controllers
88       use the mouse the same way (or at all), it's up to the specific class to
89       decide how to use this data.
90 
91       In the current implementation, the left button is tied to the X axis,
92       and the right one tied to the Y axis.
93 
94       @param xtype  The controller to use for x-axis data
95       @param xid    The controller ID to use for x-axis data (-1 for no id)
96       @param ytype  The controller to use for y-axis data
97       @param yid    The controller ID to use for y-axis data (-1 for no id)
98 
99       @return  Whether the controller supports using the mouse
100     */
101     bool setMouseControl(
102       Controller::Type xtype, int xid, Controller::Type ytype, int yid) override;
103 
104   private:
105     void nextMindlinkBit();
106 
107     // Range of valid values
108     static constexpr int MIN_POS = 0x2700;
109     static constexpr int MAX_POS = 0x3e00;
110     static constexpr int CALIBRATE_FLAG = 0x8000; // this causes a left side calibration
111 
112   private:
113     // Position value in Mindlink controller
114     // Gets transferred bitwise (16 bits)
115     int myMindlinkPos{MIN_POS};
116 
117     // Which bit to transfer next
118     int myMindlinkShift{1};
119 
120     // Whether to use the mouse to emulate this controller
121     int myMouseEnabled{false};
122 
123   private:
124     // Following constructors and assignment operators not supported
125     MindLink() = delete;
126     MindLink(const MindLink&) = delete;
127     MindLink(MindLink&&) = delete;
128     MindLink& operator=(const MindLink&) = delete;
129     MindLink& operator=(MindLink&&) = delete;
130 };
131 
132 #endif
133