stella/src/emucore/CartDPCPlus.hxx

284 lines
7.8 KiB
C++

//============================================================================
//
// 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) 1995-2017 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.
//============================================================================
#ifndef CARTRIDGE_DPC_PLUS_HXX
#define CARTRIDGE_DPC_PLUS_HXX
class System;
#ifdef THUMB_SUPPORT
#include "Thumbulator.hxx"
#endif
#ifdef DEBUGGER_SUPPORT
#include "CartDPCPlusWidget.hxx"
#endif
#include "bspf.hxx"
#include "Cart.hxx"
/**
Cartridge class used for DPC+, derived from Pitfall II. There are six 4K
program banks, a 4K display bank, 1K frequency table and the DPC chip.
DPC chip access is mapped to $1000 - $1080 ($1000 - $103F is read port,
$1040 - $107F is write port).
Program banks are accessible by read/write to $1FF6 - $1FFB.
FIXME: THIS NEEDS TO BE UPDATED
For complete details on the DPC chip see David P. Crane's United States
Patent Number 4,644,495.
@authors Darrell Spice Jr, Fred Quimby, Stephen Anthony, Bradford W. Mott
*/
class CartridgeDPCPlus : public Cartridge
{
friend class CartridgeDPCPlusWidget;
friend class CartridgeRamDPCPlusWidget;
public:
/**
Create a new cartridge using the specified image
@param image Pointer to the ROM image
@param size The size of the ROM image
@param settings A reference to the various settings (read-only)
*/
CartridgeDPCPlus(const BytePtr& image, uInt32 size, const Settings& settings);
virtual ~CartridgeDPCPlus() = default;
public:
/**
Reset device to its power-on state
*/
void reset() override;
/**
Notification method invoked by the system when the console type
has changed. We need this to inform the Thumbulator that the
timing has changed.
@param timing Enum representing the new console type
*/
void consoleChanged(ConsoleTiming timing) override;
/**
Install cartridge in the specified system. Invoked by the system
when the cartridge is attached to it.
@param system The system the device should install itself in
*/
void install(System& system) override;
/**
Install pages for the specified bank in the system.
@param bank The bank that should be installed in the system
*/
bool bank(uInt16 bank) override;
/**
Get the current bank.
*/
uInt16 getBank() const override;
/**
Query the number of banks supported by the cartridge.
*/
uInt16 bankCount() const override;
/**
Patch the cartridge ROM.
@param address The ROM address to patch
@param value The value to place into the address
@return Success or failure of the patch operation
*/
bool patch(uInt16 address, uInt8 value) override;
/**
Access the internal ROM image for this cartridge.
@param size Set to the size of the internal ROM image data
@return A pointer to the internal ROM image data
*/
const uInt8* getImage(uInt32& size) const override;
/**
Save the current state of this cart to the given Serializer.
@param out The Serializer object to use
@return False on any errors, else true
*/
bool save(Serializer& out) const override;
/**
Load the current state of this cart from the given Serializer.
@param in The Serializer object to use
@return False on any errors, else true
*/
bool load(Serializer& in) override;
/**
Get a descriptor for the device name (used in error checking).
@return The name of the object
*/
string name() const override { return "CartridgeDPC+"; }
#ifdef DEBUGGER_SUPPORT
/**
Get debugger widget responsible for accessing the inner workings
of the cart.
*/
CartDebugWidget* debugWidget(GuiObject* boss, const GUI::Font& lfont,
const GUI::Font& nfont, int x, int y, int w, int h) override
{
return new CartridgeDPCPlusWidget(boss, lfont, nfont, x, y, w, h, *this);
}
#endif
public:
/**
Get the byte at the specified address.
@return The byte at the specified address
*/
uInt8 peek(uInt16 address) override;
/**
Change the byte at the specified address to the given value
@param address The address where the value should be stored
@param value The value to be stored at the address
@return True if the poke changed the device address space, else false
*/
bool poke(uInt16 address, uInt8 value) override;
private:
/**
Sets the initial state of the DPC pointers and RAM
*/
void setInitialState();
/**
Clocks the random number generator to move it to its next state
*/
void clockRandomNumberGenerator();
/**
Clocks the random number generator to move it to its prior state
*/
void priorClockRandomNumberGenerator();
/**
Updates any data fetchers in music mode based on the number of
CPU cycles which have passed since the last update.
*/
void updateMusicModeDataFetchers();
/**
Call Special Functions
*/
void callFunction(uInt8 value);
private:
// The ROM image and size
uInt8 myImage[32768];
uInt32 mySize;
// Pointer to the 24K program ROM image of the cartridge
uInt8* myProgramImage;
// Pointer to the 4K display ROM image of the cartridge
uInt8* myDisplayImage;
// The DPC 8k RAM image, used as:
// 3K DPC+ driver
// 4K Display Data
// 1K Frequency Data
uInt8 myDPCRAM[8192];
#ifdef THUMB_SUPPORT
// Pointer to the Thumb ARM emulator object
unique_ptr<Thumbulator> myThumbEmulator;
#endif
// Pointer to the 1K frequency table
uInt8* myFrequencyImage;
// The top registers for the data fetchers
uInt8 myTops[8];
// The bottom registers for the data fetchers
uInt8 myBottoms[8];
// The counter registers for the data fetchers
uInt16 myCounters[8];
// The counter registers for the fractional data fetchers
uInt32 myFractionalCounters[8];
// The fractional increments for the data fetchers
uInt8 myFractionalIncrements[8];
// The Fast Fetcher Enabled flag
bool myFastFetch;
// Flags that last byte peeked was A9 (LDA #)
bool myLDAimmediate;
// Parameter for special functions
uInt8 myParameter[8];
// Parameter pointer for special functions
uInt8 myParameterPointer;
// The music mode counters
uInt32 myMusicCounters[3];
// The music frequency
uInt32 myMusicFrequencies[3];
// The music waveforms
uInt16 myMusicWaveforms[3];
// The random number generator register
uInt32 myRandomNumber;
// System cycle count from when the last update to music data fetchers occurred
uInt64 myAudioCycles;
// System cycle count when the last Thumbulator::run() occurred
uInt64 myARMCycles;
// Fractional DPC music OSC clocks unused during the last update
double myFractionalClocks;
// Indicates the offset into the ROM image (aligns to current bank)
uInt16 myBankOffset;
private:
// Following constructors and assignment operators not supported
CartridgeDPCPlus() = delete;
CartridgeDPCPlus(const CartridgeDPCPlus&) = delete;
CartridgeDPCPlus(CartridgeDPCPlus&&) = delete;
CartridgeDPCPlus& operator=(const CartridgeDPCPlus&) = delete;
CartridgeDPCPlus& operator=(CartridgeDPCPlus&&) = delete;
};
#endif