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Diffstat (limited to 'source/obc1.c')
| -rw-r--r-- | source/obc1.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/source/obc1.c b/source/obc1.c new file mode 100644 index 0000000..763e7cc --- /dev/null +++ b/source/obc1.c @@ -0,0 +1,204 @@ +/**************************************************** + Snes9x - Portable Super Nintendo Entertainment System (TM) emulator. + + (c) Copyright 1996 - 2002 Gary Henderson (gary.henderson@ntlworld.com) and + Jerremy Koot (jkoot@snes9x.com) + + (c) Copyright 2001 - 2004 John Weidman (jweidman@slip.net) + + (c) Copyright 2002 - 2004 Brad Jorsch (anomie@users.sourceforge.net), + funkyass (funkyass@spam.shaw.ca), + Joel Yliluoma (http://iki.fi/bisqwit/) + Kris Bleakley (codeviolation@hotmail.com), + Matthew Kendora, + Nach (n-a-c-h@users.sourceforge.net), + Peter Bortas (peter@bortas.org) and + zones (kasumitokoduck@yahoo.com) + + C4 x86 assembler and some C emulation code + (c) Copyright 2000 - 2003 zsKnight (zsknight@zsnes.com), + _Demo_ (_demo_@zsnes.com), and Nach + + C4 C++ code + (c) Copyright 2003 Brad Jorsch + + DSP-1 emulator code + (c) Copyright 1998 - 2004 Ivar (ivar@snes9x.com), _Demo_, Gary Henderson, + John Weidman, neviksti (neviksti@hotmail.com), + Kris Bleakley, Andreas Naive + + DSP-2 emulator code + (c) Copyright 2003 Kris Bleakley, John Weidman, neviksti, Matthew Kendora, and + Lord Nightmare (lord_nightmare@users.sourceforge.net + + OBC1 emulator code + (c) Copyright 2001 - 2004 zsKnight, pagefault (pagefault@zsnes.com) and + Kris Bleakley + Ported from x86 assembler to C by sanmaiwashi + + SPC7110 and RTC C++ emulator code + (c) Copyright 2002 Matthew Kendora with research by + zsKnight, John Weidman, and Dark Force + + S-DD1 C emulator code + (c) Copyright 2003 Brad Jorsch with research by + Andreas Naive and John Weidman + + S-RTC C emulator code + (c) Copyright 2001 John Weidman + + ST010 C++ emulator code + (c) Copyright 2003 Feather, Kris Bleakley, John Weidman and Matthew Kendora + + Super FX x86 assembler emulator code + (c) Copyright 1998 - 2003 zsKnight, _Demo_, and pagefault + + Super FX C emulator code + (c) Copyright 1997 - 1999 Ivar, Gary Henderson and John Weidman + + + SH assembler code partly based on x86 assembler code + (c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se) + + + Specific ports contains the works of other authors. See headers in + individual files. + + Snes9x homepage: http://www.snes9x.com + + Permission to use, copy, modify and distribute Snes9x in both binary and + source form, for non-commercial purposes, is hereby granted without fee, + providing that this license information and copyright notice appear with + all copies and any derived work. + + This software is provided 'as-is', without any express or implied + warranty. In no event shall the authors be held liable for any damages + arising from the use of this software. + + Snes9x is freeware for PERSONAL USE only. Commercial users should + seek permission of the copyright holders first. Commercial use includes + charging money for Snes9x or software derived from Snes9x. + + The copyright holders request that bug fixes and improvements to the code + should be forwarded to them so everyone can benefit from the modifications + in future versions. + + Super NES and Super Nintendo Entertainment System are trademarks of + Nintendo Co., Limited and its subsidiary companies. +*******************************************************************************/ +#include <string.h> +#include "memmap.h" +#include "obc1.h" + +static uint8 *OBC1_RAM = NULL; + +int OBC1_Address; +int OBC1_BasePtr; +int OBC1_Shift; + +extern "C" +{ +uint8 GetOBC1 (uint16 Address) +{ + switch(Address) { + case 0x7ff0: + return OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2)]; + + case 0x7ff1: + return OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 1]; + + case 0x7ff2: + return OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 2]; + + case 0x7ff3: + return OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 3]; + + case 0x7ff4: + return OBC1_RAM[OBC1_BasePtr + (OBC1_Address >> 2) + 0x200]; + } + + return OBC1_RAM[Address & 0x1fff]; +} + +void SetOBC1 (uint8 Byte, uint16 Address) +{ + switch(Address) { + case 0x7ff0: + { + OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2)] = Byte; + break; + } + + case 0x7ff1: + { + OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 1] = Byte; + break; + } + + case 0x7ff2: + { + OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 2] = Byte; + break; + } + + case 0x7ff3: + { + OBC1_RAM[OBC1_BasePtr + (OBC1_Address << 2) + 3] = Byte; + break; + } + + case 0x7ff4: + { + unsigned char Temp; + + Temp = OBC1_RAM[OBC1_BasePtr + (OBC1_Address >> 2) + 0x200]; + Temp = (Temp & ~(3 << OBC1_Shift)) | ((Byte & 3) << OBC1_Shift); + OBC1_RAM[OBC1_BasePtr + (OBC1_Address >> 2) + 0x200] = Temp; + break; + } + + case 0x7ff5: + { + if (Byte & 1) + OBC1_BasePtr = 0x1800; + else + OBC1_BasePtr = 0x1c00; + + OBC1_RAM[0x1ff5] = Byte; + break; + } + + case 0x7ff6: + { + OBC1_Address = Byte & 0x7f; + OBC1_Shift = (Byte & 3) << 1; + break; + } + + default: + OBC1_RAM[Address & 0x1fff] = Byte; + break; + } +} + +uint8 *GetBasePointerOBC1(uint32 Address) +{ + return Memory.FillRAM; +} + +uint8 *GetMemPointerOBC1(uint32 Address) +{ + return (Memory.FillRAM + (Address & 0xffff)); +} + +void ResetOBC1() +{ + OBC1_Address = 0; + OBC1_BasePtr = 0x1c00; + OBC1_Shift = 0; + OBC1_RAM = &Memory.FillRAM[0x6000]; + + memset(OBC1_RAM, 0x00, 0x2000); +} + +} |