//============================================================================ // // 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. //============================================================================ #include "System.hxx" #include "Cart2K.hxx" // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Cartridge2K::Cartridge2K(const BytePtr& image, uInt32 size, const Settings& settings) : Cartridge(settings) { // Size can be a maximum of 2K if(size > 2048) size = 2048; // Set image size to closest power-of-two for the given size mySize = 1; while(mySize < size) mySize <<= 1; // We can't use a size smaller than the minimum page size in Stella mySize = std::max(mySize, 1u << System::PAGE_SHIFT); // Initialize ROM with illegal 6502 opcode that causes a real 6502 to jam myImage = make_unique(mySize); memset(myImage.get(), 0x02, mySize); // Copy the ROM image into my buffer memcpy(myImage.get(), image.get(), size); createCodeAccessBase(mySize); // Set mask for accessing the image buffer // This is guaranteed to work, as mySize is a power of two myMask = mySize - 1; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - void Cartridge2K::reset() { myBankChanged = true; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - void Cartridge2K::install(System& system) { mySystem = &system; // Map ROM image into the system // Note that we don't need our own peek/poke methods, since the mapping // takes care of the entire address space System::PageAccess access(this, System::PA_READ); for(uInt32 address = 0x1000; address < 0x2000; address += (1 << System::PAGE_SHIFT)) { access.directPeekBase = &myImage[address & myMask]; access.codeAccessBase = &myCodeAccessBase[address & myMask]; mySystem->setPageAccess(address >> System::PAGE_SHIFT, access); } } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - bool Cartridge2K::patch(uInt16 address, uInt8 value) { myImage[address & myMask] = value; return myBankChanged = true; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - const uInt8* Cartridge2K::getImage(uInt32& size) const { size = mySize; return myImage.get(); } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - bool Cartridge2K::save(Serializer& out) const { try { out.putString(name()); } catch(...) { cerr << "ERROR: Cartridge2K::save" << endl; return false; } return true; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - bool Cartridge2K::load(Serializer& in) { try { if(in.getString() != name()) return false; } catch(...) { cerr << "ERROR: Cartridge2K::load" << endl; return false; } return true; }