www.pudn.com > Nestopia137src.zip > NstBrd8237.cpp

//////////////////////////////////////////////////////////////////////////////////////// 
// 
// Nestopia - NES/Famicom emulator written in C++ 
// 
// Copyright (C) 2003-2007 Martin Freij 
// 
// This file is part of Nestopia. 
// 
// Nestopia 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 2 of the License, or 
// (at your option) any later version. 
// 
// Nestopia 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 Nestopia; if not, write to the Free Software 
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
// 
//////////////////////////////////////////////////////////////////////////////////////// 
 
#include "../NstMapper.hpp" 
#include "NstBrdMmc3.hpp" 
#include "NstBrd8237.hpp" 
 
namespace Nes 
{ 
	namespace Core 
	{ 
		namespace Boards 
		{ 
			#ifdef NST_MSVC_OPTIMIZE 
			#pragma optimize("s", on) 
			#endif 
 
			void Unl8237::SubReset(const bool hard) 
			{ 
				if (hard) 
				{ 
					exRegs[0] = 0x00; 
					exRegs[1] = 0x00; 
				} 
 
				exRegs[2] = false; 
 
				Mmc3::SubReset( hard ); 
 
				Map( 0x5000U,          &Unl8237::Poke_5000 ); 
				Map( 0x5001U,          &Unl8237::Poke_5001 ); 
				Map( 0x8000U, 0x9FFFU, &Unl8237::Poke_8000 ); 
				Map( 0xA000U, 0xBFFFU, &Unl8237::Poke_A000 ); 
				Map( 0xC000U, 0xDFFFU, &Unl8237::Poke_C000 ); 
				Map( 0xE000U, 0xEFFFU, &Unl8237::Poke_E000 ); 
				Map( 0xF000U, 0xFFFFU, &Unl8237::Poke_F000 ); 
			} 
 
			void Unl8237::SubLoad(State::Loader& state) 
			{ 
				while (const dword chunk = state.Begin()) 
				{ 
					if (chunk == AsciiId<'R','E','G'>::V) 
					{ 
						State::Loader::Data<2> data( state ); 
 
						exRegs[0] = data[0]; 
						exRegs[1] = data[1] << 6 & 0x100; 
						exRegs[2] = data[1] & 0x1; 
					} 
 
					state.End(); 
				} 
			} 
 
			void Unl8237::SubSave(State::Saver& state) const 
			{ 
				const byte data[2] = 
				{ 
					exRegs[0], 
					exRegs[1] >> 6 | exRegs[2], 
				}; 
 
				state.Begin( AsciiId<'R','E','G'>::V ).Write( data ).End(); 
			} 
 
			#ifdef NST_MSVC_OPTIMIZE 
			#pragma optimize("", on) 
			#endif 
 
			void Unl8237::UpdatePrg() 
			{ 
				if (exRegs[0] & 0x80) 
				{ 
					const uint bank = exRegs[0] & 0xF; 
 
					if (exRegs[0] & 0x20) 
						prg.SwapBank( bank >> 1 ); 
					else 
						prg.SwapBanks( bank, bank ); 
				} 
				else 
				{ 
					Mmc3::UpdatePrg(); 
				} 
			} 
 
			void Unl8237::UpdateChr() const 
			{ 
				ppu.Update(); 
 
				const uint swap = (regs.ctrl0 & Regs::CTRL0_XOR_CHR) << 5; 
 
				chr.SwapBanks 
				( 
					0x0000 ^ swap, 
					exRegs[1] >> 1 | banks.chr[0], 
					exRegs[1] >> 1 | banks.chr[1] 
				); 
 
				chr.SwapBanks 
				( 
					0x1000 ^ swap, 
					exRegs[1] | banks.chr[2], 
					exRegs[1] | banks.chr[3], 
					exRegs[1] | banks.chr[4], 
					exRegs[1] | banks.chr[5] 
				); 
			} 
 
			NES_POKE_D(Unl8237,5000) 
			{ 
				if (exRegs[0] != data) 
				{ 
					exRegs[0] = data; 
					UpdatePrg(); 
				} 
			} 
 
			NES_POKE_D(Unl8237,5001) 
			{ 
				data = data << 6 & 0x100; 
 
				if (exRegs[1] != data) 
				{ 
					exRegs[1] = data; 
					UpdateChr(); 
				} 
			} 
 
			NES_POKE_D(Unl8237,8000) 
			{ 
				SetMirroringHV( data >> 7 | data ); 
			} 
 
			NES_POKE_D(Unl8237,A000) 
			{ 
				static const byte lut[8] = {0,2,6,1,7,3,4,5}; 
 
				data = (data & 0xC0) | lut[data & 0x07]; 
				exRegs[2] = true; 
 
				Mmc3::NES_DO_POKE(8000,0x8000,data); 
			} 
 
			NES_POKE_D(Unl8237,C000) 
			{ 
				if (exRegs[2]) 
				{ 
					exRegs[2] = false; 
					Mmc3::NES_DO_POKE(8001,0x8001,data); 
				} 
			} 
 
			NES_POKE_D(Unl8237,F000) 
			{ 
				Mmc3::NES_DO_POKE(E001,0xE001,data); 
				Mmc3::NES_DO_POKE(C000,0xC000,data); 
				Mmc3::NES_DO_POKE(C001,0xC001,data); 
			} 
		} 
	} 
}