Analog input refactoring and improvements

* Lazily update readout circuit simulation as soon as the pin
      changes
    * Always assume that "max resistance" means "connected to ground"
    * Minor accuracy improvements

src/emucore/AmigaMouse.cxx

@@ -36,9 +36,6 @@ AmigaMouse::AmigaMouse(Jack jack, const Event& event, const System& system)
 
   myTrakBallLeft = myTrakBallDown = myScanCountV = myScanCountH =
     myCountV = myCountH = 0;
-
-  // Analog pins are never used by the trakball controller
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/AtariMouse.cxx

@@ -36,9 +36,6 @@ AtariMouse::AtariMouse(Jack jack, const Event& event, const System& system)
 
   myTrakBallLeft = myTrakBallDown = myScanCountV = myScanCountH =
     myCountV = myCountH = 0;
-
-  // Analog pins are never used by the Atari ST mouse controller
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/AtariVox.cxx

@@ -39,8 +39,6 @@ AtariVox::AtariVox(Jack jack, const Event& event, const System& system,
 
   myDigitalPinState[One] = myDigitalPinState[Two] =
   myDigitalPinState[Three] = myDigitalPinState[Four] = true;
-
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Booster.cxx

@@ -61,10 +61,14 @@ void BoosterGrip::update()
 
   // The CBS Booster-grip has two more buttons on it.  These buttons are
   // connected to the inputs usually used by paddles.
-  myAnalogPinValue[Five] = (myEvent.get(myTriggerEvent) != 0) ?
+  updateAnalogPin(
-                            minimumResistance : maximumResistance;
+    Five,
-  myAnalogPinValue[Nine] = (myEvent.get(myBoosterEvent) != 0) ?
+    (myEvent.get(myTriggerEvent) != 0) ? minimumResistance : maximumResistance
-                            minimumResistance : maximumResistance;
+  );
+  updateAnalogPin(
+    Nine,
+    (myEvent.get(myBoosterEvent) != 0) ? minimumResistance : maximumResistance
+  );
 
   // Axis events (usually generated by the Stelladaptor)
   int xaxis = myEvent.get(myXAxisValue);
@@ -117,7 +121,7 @@ void BoosterGrip::update()
     if(myEvent.get(Event::MouseButtonLeftValue))
       myDigitalPinState[Six] = false;
     if(myEvent.get(Event::MouseButtonRightValue))
-      myAnalogPinValue[Nine] = minimumResistance;
+      updateAnalogPin(Nine, minimumResistance);
   }
 }
 

src/emucore/CompuMate.cxx

@@ -32,10 +32,10 @@ CompuMate::CompuMate(const Console& console, const Event& event,
   myLeftController  = make_ptr<CMControl>(*this, Controller::Left, event, system);
   myRightController = make_ptr<CMControl>(*this, Controller::Right, event, system);
 
-  myLeftController->myAnalogPinValue[Controller::Nine] = Controller::maximumResistance;
+  myLeftController->updateAnalogPin(Controller::Nine, Controller::maximumResistance);
-  myLeftController->myAnalogPinValue[Controller::Five] = Controller::minimumResistance;
+  myLeftController->updateAnalogPin(Controller::Five, Controller::minimumResistance);
-  myRightController->myAnalogPinValue[Controller::Nine] = Controller::minimumResistance;
+  myRightController->updateAnalogPin(Controller::Nine, Controller::minimumResistance);
-  myRightController->myAnalogPinValue[Controller::Five] = Controller::maximumResistance;
+  myRightController->updateAnalogPin(Controller::Five, Controller::maximumResistance);
 
   enableKeyHandling(false);
 }
@@ -61,6 +61,7 @@ void CompuMate::update()
   Controller& lp = myConsole.leftController();
   Controller& rp = myConsole.rightController();
 
+
   lp.myAnalogPinValue[Controller::Nine] = Controller::maximumResistance;
   lp.myAnalogPinValue[Controller::Five] = Controller::minimumResistance;
   lp.myDigitalPinState[Controller::Six] = true;
@@ -196,4 +197,14 @@ void CompuMate::update()
     default:
       break;
   }
+
+  if (lp.myOnAnalogPinUpdateCallback) {
+    lp.myOnAnalogPinUpdateCallback(Controller::Five);
+    lp.myOnAnalogPinUpdateCallback(Controller::Nine);
+  }
+
+  if (rp.myOnAnalogPinUpdateCallback) {
+    rp.myOnAnalogPinUpdateCallback(Controller::Five);
+    rp.myOnAnalogPinUpdateCallback(Controller::Nine);
+  }
 }

src/emucore/Console.cxx

@@ -855,6 +855,8 @@ void Console::setControllers(const string& rommd5)
     myLeftControl  = std::move(rightC);
     myRightControl = std::move(leftC);
   }
+
+  myTIA->bindToControllers();
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Control.cxx

@@ -26,7 +26,8 @@ Controller::Controller(Jack jack, const Event& event, const System& system,
   : myJack(jack),
     myEvent(event),
     mySystem(system),
-    myType(type)
+    myType(type),
+    myOnAnalogPinUpdateCallback(0)
 {
   myDigitalPinState[One]   =
   myDigitalPinState[Two]   =
@@ -115,8 +116,18 @@ void Controller::set(DigitalPin pin, bool value)
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void Controller::set(AnalogPin pin, Int32 value)
+{
+  updateAnalogPin(pin, value);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void Controller::updateAnalogPin(AnalogPin pin, Int32 value)
 {
   myAnalogPinValue[pin] = value;
+
+  if (myOnAnalogPinUpdateCallback) {
+    myOnAnalogPinUpdateCallback(pin);
+  }
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Control.hxx

@@ -22,6 +22,8 @@ class Controller;
 class Event;
 class System;
 
+#include <functional>
+
 #include "Serializable.hxx"
 #include "bspf.hxx"
 
@@ -92,6 +94,11 @@ class Controller : public Serializable
       Paddles, SaveKey, TrakBall
     };
 
+    /**
+      Callback type for analog pin updates
+    */
+    using onAnalogPinUpdateCallback = std::function<void(AnalogPin)>;
+
   public:
     /**
       Create a new controller plugged into the specified jack
@@ -237,6 +244,13 @@ class Controller : public Serializable
     */
     string name() const override { return myName; }
 
+    /**
+      Inject a callback to be notified on analog pin updates.
+    */
+    void setOnAnalogPinUpdateCallback(onAnalogPinUpdateCallback callback) {
+      myOnAnalogPinUpdateCallback = callback;
+    }
+
   public:
     /// Constant which represents maximum resistance for analog pins
     static constexpr Int32 maximumResistance = 0x7FFFFFFF;
@@ -244,6 +258,9 @@ class Controller : public Serializable
     /// Constant which represents minimum resistance for analog pins
     static constexpr Int32 minimumResistance = 0x00000000;
 
+  protected:
+    void updateAnalogPin(AnalogPin, Int32 value);
+
   protected:
     /// Specifies which jack the controller is plugged in
     const Jack myJack;
@@ -263,6 +280,10 @@ class Controller : public Serializable
     /// The boolean value on each digital pin
     bool myDigitalPinState[5];
 
+    /// The callback that is dispatched whenver an analog pin has changed
+    onAnalogPinUpdateCallback myOnAnalogPinUpdateCallback;
+
+  private:
     /// The analog value on each analog pin
     Int32 myAnalogPinValue[2];
 

src/emucore/Driving.cxx

@@ -49,9 +49,6 @@ Driving::Driving(Jack jack, const Event& event, const System& system)
 
   // Digital pins 3 and 4 are not connected
   myDigitalPinState[Three] = myDigitalPinState[Four] = true;
-
-  // Analog pins are not connected
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Genesis.cxx

@@ -41,11 +41,6 @@ Genesis::Genesis(Jack jack, const Event& event, const System& system)
     myFire1Event   = Event::JoystickOneFire;
     myFire2Event   = Event::JoystickOneFire5;
   }
-
-  // Analog pin 9 is not connected to this controller at all
-  // Analog pin 5 corresponds to button 'C' on the gamepad, and corresponds
-  // to the 'booster' button on a BoosterGrip controller
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -61,8 +56,10 @@ void Genesis::update()
   // The Genesis has one more button (C) that can be read by the 2600
   // However, it seems to work opposite to the BoosterGrip controller,
   // in that the logic is inverted
-  myAnalogPinValue[Five] = (myEvent.get(myFire2Event) == 0) ?
+  updateAnalogPin(
-                            minimumResistance : maximumResistance;
+    Five,
+    (myEvent.get(myFire2Event) == 0) ? minimumResistance : maximumResistance
+  );
 
   // Mouse motion and button events
   if(myControlID > -1)
@@ -93,7 +90,7 @@ void Genesis::update()
     if(myEvent.get(Event::MouseButtonLeftValue))
       myDigitalPinState[Six] = false;
     if(myEvent.get(Event::MouseButtonRightValue))
-      myAnalogPinValue[Five] = maximumResistance;
+      updateAnalogPin(Five, maximumResistance);
   }
 }
 

src/emucore/Joystick.cxx

@@ -43,9 +43,6 @@ Joystick::Joystick(Jack jack, const Event& event, const System& system)
     myXAxisValue = Event::SARightAxis0Value;
     myYAxisValue = Event::SARightAxis1Value;
   }
-
-  // Analog pins are never used by the joystick
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Keyboard.cxx

@@ -61,32 +61,39 @@ void Keyboard::write(DigitalPin pin, bool value)
 
   // Set defaults
   myDigitalPinState[Six] = true;
-  myAnalogPinValue[Five] = minimumResistance;
+  Int32 resistanceFive = MIN_RESISTANCE;
-  myAnalogPinValue[Nine] = minimumResistance;
+  Int32 resistanceNine = MIN_RESISTANCE;
 
   // Now scan the rows and columns
   if(!myDigitalPinState[Four])
   {
     myDigitalPinState[Six] = (myEvent.get(myPoundEvent) == 0);
-    if(myEvent.get(myZeroEvent) != 0) myAnalogPinValue[Five] = maximumResistance;
+    if(myEvent.get(myZeroEvent) != 0) resistanceFive = maximumResistance;
-    if(myEvent.get(myStarEvent) != 0) myAnalogPinValue[Nine] = maximumResistance;
+    if(myEvent.get(myStarEvent) != 0) resistanceNine = maximumResistance;
   }
   if(!myDigitalPinState[Three])
   {
     myDigitalPinState[Six] = (myEvent.get(myNineEvent) == 0);
-    if(myEvent.get(myEightEvent) != 0) myAnalogPinValue[Five] = maximumResistance;
+    if(myEvent.get(myEightEvent) != 0) resistanceFive = maximumResistance;
-    if(myEvent.get(mySevenEvent) != 0) myAnalogPinValue[Nine] = maximumResistance;
+    if(myEvent.get(mySevenEvent) != 0) resistanceNine = maximumResistance;
   }
   if(!myDigitalPinState[Two])
   {
     myDigitalPinState[Six] = (myEvent.get(mySixEvent) == 0);
-    if(myEvent.get(myFiveEvent) != 0) myAnalogPinValue[Five] = maximumResistance;
+    if(myEvent.get(myFiveEvent) != 0) resistanceFive = maximumResistance;
-    if(myEvent.get(myFourEvent) != 0) myAnalogPinValue[Nine] = maximumResistance;
+    if(myEvent.get(myFourEvent) != 0) resistanceNine = maximumResistance;
   }
   if(!myDigitalPinState[One])
   {
     myDigitalPinState[Six] = (myEvent.get(myThreeEvent) == 0);
-    if(myEvent.get(myTwoEvent) != 0) myAnalogPinValue[Five] = maximumResistance;
+    if(myEvent.get(myTwoEvent) != 0) resistanceFive = maximumResistance;
-    if(myEvent.get(myOneEvent) != 0) myAnalogPinValue[Nine] = maximumResistance;
+    if(myEvent.get(myOneEvent) != 0) resistanceNine = maximumResistance;
   }
+
+  if (resistanceFive != read(Five)) {
+    updateAnalogPin(Five, resistanceFive);
+  }
+
+  if (resistanceNine != read(Nine))
+    updateAnalogPin(Nine, resistanceNine);
 }

src/emucore/Keyboard.hxx

@@ -65,6 +65,8 @@ class Keyboard : public Controller
                 mySevenEvent, myEightEvent, myNineEvent,
                 myStarEvent, myZeroEvent, myPoundEvent;
 
+    static constexpr Int32 MIN_RESISTANCE = 5600;
+
   private:
     // Following constructors and assignment operators not supported
     Keyboard() = delete;

src/emucore/KidVid.cxx

@@ -46,10 +46,6 @@ KidVid::KidVid(Jack jack, const Event& event, const System& system,
     myGame = KVSMURFS;    // Smurfs Save the Day
   else
     myEnabled = false;
-
-  // Analog pins are never used by the KidVid controller
-  // (at least not in this implementation)
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/M6532.cxx

@@ -17,6 +17,7 @@
 
 #include <cassert>
 #include <iostream>
+#include <bitset>
 
 #include "Console.hxx"
 #include "Settings.hxx"

src/emucore/MindLink.cxx

@@ -29,9 +29,6 @@ MindLink::MindLink(Jack jack, const Event& event, const System& system)
   myDigitalPinState[Two]   = true;
   myDigitalPinState[Three] = true;
   myDigitalPinState[Four]  = true;
-
-  // Analog pins are never used by the MindLink
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/Paddles.cxx

@@ -28,7 +28,8 @@ Paddles::Paddles(Jack jack, const Event& event, const System& system,
 {
   // We must start with minimum resistance; see commit
   // 38b452e1a047a0dca38c5bcce7c271d40f76736e for more information
-  myAnalogPinValue[Nine] = myAnalogPinValue[Five] = minimumResistance;
+  updateAnalogPin(Five, minimumResistance);
+  updateAnalogPin(Nine, minimumResistance);
 
   // The following logic reflects that mapping paddles to different
   // devices can be extremely complex
@@ -260,12 +261,12 @@ void Paddles::update()
   int sa_yaxis = myEvent.get(myP1AxisValue);
   if(abs(myLastAxisX - sa_xaxis) > 10)
   {
-    myAnalogPinValue[Nine] = Int32(MAX_RESISTANCE * ((32767 - Int16(sa_xaxis)) / 65536.0));
+    updateAnalogPin(Nine, Int32(MAX_RESISTANCE * ((32767 - Int16(sa_xaxis)) / 65536.0)));
     sa_changed = true;
   }
   if(abs(myLastAxisY - sa_yaxis) > 10)
   {
-    myAnalogPinValue[Five] = Int32(MAX_RESISTANCE * ((32767 - Int16(sa_yaxis)) / 65536.0));
+    updateAnalogPin(Five, Int32(MAX_RESISTANCE * ((32767 - Int16(sa_yaxis)) / 65536.0)));
     sa_changed = true;
   }
   myLastAxisX = sa_xaxis;
@@ -352,11 +353,9 @@ void Paddles::update()
 
   // Only change state if the charge has actually changed
   if(myCharge[1] != myLastCharge[1])
-    myAnalogPinValue[Five] =
+    updateAnalogPin(Five, Int32(MAX_RESISTANCE * (myCharge[1] / float(TRIGMAX))));
-        Int32(MAX_RESISTANCE * (myCharge[1] / float(TRIGMAX)));
   if(myCharge[0] != myLastCharge[0])
-    myAnalogPinValue[Nine] =
+    updateAnalogPin(Nine, Int32(MAX_RESISTANCE * (myCharge[0] / float(TRIGMAX))));
-        Int32(MAX_RESISTANCE * (myCharge[0] / float(TRIGMAX)));
 
   myLastCharge[1] = myCharge[1];
   myLastCharge[0] = myCharge[0];

src/emucore/SaveKey.cxx

@@ -27,7 +27,6 @@ SaveKey::SaveKey(Jack jack, const Event& event, const System& system,
   myEEPROM = make_ptr<MT24LC256>(eepromfile, system);
 
   myDigitalPinState[One] = myDigitalPinState[Two] = true;
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/TrakBall.cxx

@@ -38,9 +38,6 @@ TrakBall::TrakBall(Jack jack, const Event& event, const System& system)
 
   myTrakBallLeft = myTrakBallDown = myScanCountV = myScanCountH =
     myCountV = myCountH = 0;
-
-  // Analog pins are never used by the trakball controller
-  myAnalogPinValue[Five] = myAnalogPinValue[Nine] = maximumResistance;
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

src/emucore/tia/PaddleReader.cxx

@@ -22,10 +22,10 @@
 static constexpr double
   C = 68e-9,
   RPOT = 1e6,
-  R0 = 1.8e3,
+  R0 = 1.5e3,
   USUPP = 5;
 
-static constexpr double TRIPPOINT_LINES = 380;
+static constexpr double TRIPPOINT_LINES = 379;
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 PaddleReader::PaddleReader()
@@ -79,9 +79,18 @@ void PaddleReader::update(double value, double timestamp, ConsoleTiming consoleT
 
   if (value != myValue) {
     myValue = value;
+
+    if (myValue < 0) {
+      // value < 0 signifies either maximum resistance OR analog input connected to
+      // ground (keyboard controllers). As we have no way to tell these apart we just
+      // assume ground and discharge.
+      myU = 0;
+      myTimestamp = timestamp;
+    } else {
       updateCharge(timestamp);
     }
   }
+}
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void PaddleReader::setConsoleTiming(ConsoleTiming consoleTiming)

src/emucore/tia/TIA.cxx

@@ -334,6 +334,45 @@ bool TIA::load(Serializer& in)
   return true;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void TIA::bindToControllers()
+{
+  myConsole.leftController().setOnAnalogPinUpdateCallback(
+    [this] (Controller::AnalogPin pin) {
+      TIA& tia = mySystem->tia();
+
+      switch (pin) {
+        case Controller::AnalogPin::Five:
+          tia.updatePaddle(1);
+          break;
+
+        case Controller::AnalogPin::Nine:
+          tia.updatePaddle(0);
+          break;
+      }
+    }
+  );
+
+  myConsole.rightController().setOnAnalogPinUpdateCallback(
+    [this] (Controller::AnalogPin pin) {
+      TIA& tia = mySystem->tia();
+
+      switch (pin) {
+        case Controller::AnalogPin::Five:
+          tia.updatePaddle(3);
+          break;
+
+        case Controller::AnalogPin::Nine:
+          tia.updatePaddle(2);
+          break;
+      }
+    }
+  );
+
+  for (uInt8 i = 0; i < 4; i++)
+    updatePaddle(i);
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 uInt8 TIA::peek(uInt16 address)
 {
@@ -1032,9 +1071,6 @@ void TIA::onFrameStart()
 {
   myXAtRenderingStart = 0;
 
-  for (uInt8 i = 0; i < 4; i++)
-    updatePaddle(i);
-
   // Check for colour-loss emulation
   if (myColorLossEnabled)
   {
@@ -1452,7 +1488,7 @@ void TIA::updatePaddle(uInt8 idx)
   }
 
   myPaddleReaders[idx].update(
-    (resistance == Controller::maximumResistance ? -1 : double(resistance)) / Paddles::MAX_RESISTANCE,
+    (resistance == Controller::maximumResistance) ? -1 : (double(resistance) / Paddles::MAX_RESISTANCE),
     myTimestamp,
     consoleTiming()
   );

src/emucore/tia/TIA.hxx

@@ -37,6 +37,7 @@
 #include "LatchedInput.hxx"
 #include "PaddleReader.hxx"
 #include "DelayQueueIterator.hxx"
+#include "Control.hxx"
 
 /**
   This class is a device that emulates the Television Interface Adaptor
@@ -146,6 +147,11 @@ class TIA : public Device
     */
     void installDelegate(System& system, Device& device);
 
+    /**
+      Bind to controllers.
+    */
+    void bindToControllers();
+
     /**
       The following are very similar to save() and load(), except they
       do a 'deeper' save of the display data itself.