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authorLouis Burda <quent.burda@gmail.com>2022-06-02 15:28:40 +0200
committerLouis Burda <quent.burda@gmail.com>2022-06-02 15:28:40 +0200
commit5bc16063c29aa4d3d287ebd163ccdbcbf54c4f9f (patch)
treec131f947a37b3af2d14d41e9eda098bdec2d061c /gearboy/src/MBC5MemoryRule.cpp
parent78a5f810b22f0d8cafa05f638b0cb2e889824859 (diff)
downloadcscg2022-gearboy-master.tar.gz
cscg2022-gearboy-master.zip
Added submodule filesHEADmaster
Diffstat (limited to 'gearboy/src/MBC5MemoryRule.cpp')
-rw-r--r--gearboy/src/MBC5MemoryRule.cpp254
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diff --git a/gearboy/src/MBC5MemoryRule.cpp b/gearboy/src/MBC5MemoryRule.cpp
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+/*
+ * Gearboy - Nintendo Game Boy Emulator
+ * Copyright (C) 2012 Ignacio Sanchez
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see http://www.gnu.org/licenses/
+ *
+ */
+
+#include "MBC5MemoryRule.h"
+#include "Video.h"
+#include "Memory.h"
+#include "Processor.h"
+#include "Input.h"
+#include "Cartridge.h"
+
+MBC5MemoryRule::MBC5MemoryRule(Processor* pProcessor,
+ Memory* pMemory, Video* pVideo, Input* pInput,
+ Cartridge* pCartridge, Audio* pAudio) : MemoryRule(pProcessor,
+pMemory, pVideo, pInput, pCartridge, pAudio)
+{
+ m_pRAMBanks = new u8[0x20000];
+ Reset(false);
+}
+
+MBC5MemoryRule::~MBC5MemoryRule()
+{
+ SafeDeleteArray(m_pRAMBanks);
+}
+
+void MBC5MemoryRule::Reset(bool bCGB)
+{
+ m_bCGB = bCGB;
+ m_iCurrentRAMBank = 0;
+ m_iCurrentROMBank = 1;
+ m_iCurrentROMBankHi = 0;
+ m_bRamEnabled = false;
+ for (int i = 0; i < 0x20000; i++)
+ m_pRAMBanks[i] = 0xFF;
+ m_CurrentROMAddress = 0x4000;
+ m_CurrentRAMAddress = 0;
+}
+
+u8 MBC5MemoryRule::PerformRead(u16 address)
+{
+ switch (address & 0xE000)
+ {
+ case 0x4000:
+ case 0x6000:
+ {
+ u8* pROM = m_pCartridge->GetTheROM();
+ return pROM[(address - 0x4000) + m_CurrentROMAddress];
+ }
+ case 0xA000:
+ {
+ if (m_bRamEnabled)
+ {
+ return m_pRAMBanks[(address - 0xA000) + m_CurrentRAMAddress];
+ }
+ else
+ {
+ Log("--> ** Attempting to read from disabled ram %X", address);
+ return 0xFF;
+ }
+ }
+ default:
+ {
+ return m_pMemory->Retrieve(address);
+ }
+ }
+}
+
+void MBC5MemoryRule::PerformWrite(u16 address, u8 value)
+{
+ switch (address & 0xE000)
+ {
+ case 0x0000:
+ {
+ if (m_pCartridge->GetRAMSize() > 0)
+ {
+ bool previous = m_bRamEnabled;
+ m_bRamEnabled = ((value & 0x0F) == 0x0A);
+
+ if (IsValidPointer(m_pRamChangedCallback) && previous && !m_bRamEnabled)
+ {
+ (*m_pRamChangedCallback)();
+ }
+ }
+ break;
+ }
+ case 0x2000:
+ {
+ if (address < 0x3000)
+ {
+ m_iCurrentROMBank = value | (m_iCurrentROMBankHi << 8);
+ }
+ else
+ {
+ m_iCurrentROMBankHi = value & 0x01;
+ m_iCurrentROMBank = (m_iCurrentROMBank & 0xFF) | (m_iCurrentROMBankHi << 8);
+ }
+ m_iCurrentROMBank &= (m_pCartridge->GetROMBankCount() - 1);
+ m_CurrentROMAddress = m_iCurrentROMBank * 0x4000;
+ break;
+ }
+ case 0x4000:
+ {
+ m_iCurrentRAMBank = value & 0x0F;
+ m_iCurrentRAMBank &= (m_pCartridge->GetRAMBankCount() - 1);
+ m_CurrentRAMAddress = m_iCurrentRAMBank * 0x2000;
+ break;
+ }
+ case 0x6000:
+ {
+ Log("--> ** Attempting to write on invalid address %X %X", address, value);
+ break;
+ }
+ case 0xA000:
+ {
+ if (m_bRamEnabled)
+ {
+ m_pRAMBanks[(address - 0xA000) + m_CurrentRAMAddress] = value;
+ }
+ else
+ {
+ Log("--> ** Attempting to write on RAM when ram is disabled %X %X", address, value);
+ }
+ break;
+ }
+ default:
+ {
+ m_pMemory->Load(address, value);
+ break;
+ }
+ }
+}
+
+void MBC5MemoryRule::SaveRam(std::ostream & file)
+{
+ Log("MBC5MemoryRule save RAM...");
+ Log("MBC5MemoryRule saving %d banks...", m_pCartridge->GetRAMBankCount());
+
+ s32 ramSize = m_pCartridge->GetRAMBankCount() * 0x2000;
+
+ for (s32 i = 0; i < ramSize; i++)
+ {
+ u8 ram_byte = m_pRAMBanks[i];
+ file.write(reinterpret_cast<const char*> (&ram_byte), 1);
+ }
+
+ Log("MBC5MemoryRule save RAM done");
+}
+
+bool MBC5MemoryRule::LoadRam(std::istream & file, s32 fileSize)
+{
+ Log("MBC5MemoryRule load RAM...");
+ Log("MBC5MemoryRule loading %d banks...", m_pCartridge->GetRAMBankCount());
+
+ s32 ramSize = m_pCartridge->GetRAMBankCount() * 0x2000;
+
+ if ((fileSize > 0) && (fileSize != ramSize))
+ {
+ Log("MBC5MemoryRule incorrect size. Expected: %d Found: %d", ramSize, fileSize);
+ return false;
+ }
+
+ for (s32 i = 0; i < ramSize; i++)
+ {
+ u8 ram_byte = 0;
+ file.read(reinterpret_cast<char*> (&ram_byte), 1);
+ m_pRAMBanks[i] = ram_byte;
+ }
+
+ Log("MBC5MemoryRule load RAM done");
+
+ return true;
+}
+
+size_t MBC5MemoryRule::GetRamSize()
+{
+ return m_pCartridge->GetRAMBankCount() * 0x2000;
+}
+
+u8* MBC5MemoryRule::GetRamBanks()
+{
+ return m_pRAMBanks;
+}
+
+u8* MBC5MemoryRule::GetCurrentRamBank()
+{
+ return m_pRAMBanks + m_CurrentRAMAddress;
+}
+
+int MBC5MemoryRule::GetCurrentRamBankIndex()
+{
+ return m_iCurrentRAMBank;
+}
+
+u8* MBC5MemoryRule::GetRomBank0()
+{
+ return m_pMemory->GetMemoryMap() + 0x0000;
+}
+
+int MBC5MemoryRule::GetCurrentRomBank0Index()
+{
+ return 0;
+}
+
+u8* MBC5MemoryRule::GetCurrentRomBank1()
+{
+ u8* pROM = m_pCartridge->GetTheROM();
+ return &pROM[m_CurrentROMAddress];
+}
+
+int MBC5MemoryRule::GetCurrentRomBank1Index()
+{
+ return m_iCurrentROMBank;
+}
+
+void MBC5MemoryRule::SaveState(std::ostream& stream)
+{
+ using namespace std;
+
+ stream.write(reinterpret_cast<const char*> (&m_iCurrentRAMBank), sizeof(m_iCurrentRAMBank));
+ stream.write(reinterpret_cast<const char*> (&m_iCurrentROMBank), sizeof(m_iCurrentROMBank));
+ stream.write(reinterpret_cast<const char*> (&m_iCurrentROMBankHi), sizeof(m_iCurrentROMBankHi));
+ stream.write(reinterpret_cast<const char*> (&m_bRamEnabled), sizeof(m_bRamEnabled));
+ stream.write(reinterpret_cast<const char*> (m_pRAMBanks), 0x20000);
+ stream.write(reinterpret_cast<const char*> (&m_CurrentROMAddress), sizeof(m_CurrentROMAddress));
+ stream.write(reinterpret_cast<const char*> (&m_CurrentRAMAddress), sizeof(m_CurrentRAMAddress));
+}
+
+void MBC5MemoryRule::LoadState(std::istream& stream)
+{
+ using namespace std;
+
+ stream.read(reinterpret_cast<char*> (&m_iCurrentRAMBank), sizeof(m_iCurrentRAMBank));
+ stream.read(reinterpret_cast<char*> (&m_iCurrentROMBank), sizeof(m_iCurrentROMBank));
+ stream.read(reinterpret_cast<char*> (&m_iCurrentROMBankHi), sizeof(m_iCurrentROMBankHi));
+ stream.read(reinterpret_cast<char*> (&m_bRamEnabled), sizeof(m_bRamEnabled));
+ stream.read(reinterpret_cast<char*> (m_pRAMBanks), 0x20000);
+ stream.read(reinterpret_cast<char*> (&m_CurrentROMAddress), sizeof(m_CurrentROMAddress));
+ stream.read(reinterpret_cast<char*> (&m_CurrentRAMAddress), sizeof(m_CurrentRAMAddress));
+}