git.maemo.org Git - drnoksnes/blob - seta018.cpp

   1 /*******************************************************************************
   2   Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
   3
   4   (c) Copyright 1996 - 2002 Gary Henderson (gary.henderson@ntlworld.com) and
   5                             Jerremy Koot (jkoot@snes9x.com)
   6
   7   (c) Copyright 2001 - 2004 John Weidman (jweidman@slip.net)
   8
   9   (c) Copyright 2002 - 2004 Brad Jorsch (anomie@users.sourceforge.net),
  10                             funkyass (funkyass@spam.shaw.ca),
  11                             Joel Yliluoma (http://iki.fi/bisqwit/)
  12                             Kris Bleakley (codeviolation@hotmail.com),
  13                             Matthew Kendora,
  14                             Nach (n-a-c-h@users.sourceforge.net),
  15                             Peter Bortas (peter@bortas.org) and
  16                             zones (kasumitokoduck@yahoo.com)
  17
  18   C4 x86 assembler and some C emulation code
  19   (c) Copyright 2000 - 2003 zsKnight (zsknight@zsnes.com),
  20                             _Demo_ (_demo_@zsnes.com), and Nach
  21
  22   C4 C++ code
  23   (c) Copyright 2003 Brad Jorsch
  24
  25   DSP-1 emulator code
  26   (c) Copyright 1998 - 2004 Ivar (ivar@snes9x.com), _Demo_, Gary Henderson,
  27                             John Weidman, neviksti (neviksti@hotmail.com),
  28                             Kris Bleakley, Andreas Naive
  29
  30   DSP-2 emulator code
  31   (c) Copyright 2003 Kris Bleakley, John Weidman, neviksti, Matthew Kendora, and
  32                      Lord Nightmare (lord_nightmare@users.sourceforge.net
  33
  34   OBC1 emulator code
  35   (c) Copyright 2001 - 2004 zsKnight, pagefault (pagefault@zsnes.com) and
  36                             Kris Bleakley
  37   Ported from x86 assembler to C by sanmaiwashi
  38
  39   SPC7110 and RTC C++ emulator code
  40   (c) Copyright 2002 Matthew Kendora with research by
  41                      zsKnight, John Weidman, and Dark Force
  42
  43   S-DD1 C emulator code
  44   (c) Copyright 2003 Brad Jorsch with research by
  45                      Andreas Naive and John Weidman
  46
  47   S-RTC C emulator code
  48   (c) Copyright 2001 John Weidman
  49
  50   ST010 C++ emulator code
  51   (c) Copyright 2003 Feather, Kris Bleakley, John Weidman and Matthew Kendora
  52
  53   Super FX x86 assembler emulator code
  54   (c) Copyright 1998 - 2003 zsKnight, _Demo_, and pagefault
  55
  56   Super FX C emulator code
  57   (c) Copyright 1997 - 1999 Ivar, Gary Henderson and John Weidman
  58
  59
  60   SH assembler code partly based on x86 assembler code
  61   (c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se)
  62
  63
  64   Specific ports contains the works of other authors. See headers in
  65   individual files.
  66
  67   Snes9x homepage: http://www.snes9x.com
  68
  69   Permission to use, copy, modify and distribute Snes9x in both binary and
  70   source form, for non-commercial purposes, is hereby granted without fee,
  71   providing that this license information and copyright notice appear with
  72   all copies and any derived work.
  73
  74   This software is provided 'as-is', without any express or implied
  75   warranty. In no event shall the authors be held liable for any damages
  76   arising from the use of this software.
  77
  78   Snes9x is freeware for PERSONAL USE only. Commercial users should
  79   seek permission of the copyright holders first. Commercial use includes
  80   charging money for Snes9x or software derived from Snes9x.
  81
  82   The copyright holders request that bug fixes and improvements to the code
  83   should be forwarded to them so everyone can benefit from the modifications
  84   in future versions.
  85
  86   Super NES and Super Nintendo Entertainment System are trademarks of
  87   Nintendo Co., Limited and its subsidiary companies.
  88 *******************************************************************************/
  89 #include "memmap.h"
  90 #include "seta.h"
  91 //#include "port.h"
  92
  93 ST018_Regs ST018;
  94
  95 static int line;        // line counter
  96
  97 extern "C"{
  98 uint8 S9xGetST018(uint32 Address)
  99 {
 100         uint8 t = 0;
 101         uint16 address = (uint16) Address & 0xFFFF;
 102
 103         line++;
 104
 105         // these roles may be flipped
 106         // op output
 107         if (address == 0x3804)
 108         {
 109                 if (ST018.out_count)
 110                 {
 111                         t = (uint8) ST018.output [ST018.out_index];
 112                         ST018.out_index++;
 113                         if (ST018.out_count==ST018.out_index)
 114                                 ST018.out_count=0;
 115                 }
 116                 else
 117                         t = 0x81;
 118         }
 119         // status register
 120         else if (address == 0x3800)
 121                 t = ST018.status;
 122
 123         printf( "ST018 R: %06X %02X\n", Address, t);
 124
 125         return t;
 126 }
 127
 128 void S9xSetST018(uint8 Byte, uint32 Address)
 129 {
 130         uint16 address = (uint16) Address&0xFFFF;
 131         static bool reset = false;
 132
 133         printf( "ST018 W: %06X %02X\n", Address, Byte );
 134
 135         line++;
 136
 137         if (!reset)
 138         {
 139                 // bootup values
 140                 ST018.waiting4command = true;
 141                 ST018.part_command = 0;
 142                 reset = true;
 143         }
 144
 145         Memory.SRAM[address]=Byte;
 146
 147         // default status for now
 148         ST018.status = 0x00;
 149
 150         // op data goes through this address
 151         if (address==0x3804)
 152         {
 153                 // check for new commands: 3 bytes length
 154                 if(ST018.waiting4command && ST018.part_command==2)
 155                 {
 156                         ST018.waiting4command = false;
 157                         ST018.command <<= 8;
 158                         ST018.command |= Byte;
 159                         ST018.in_index = 0;
 160                         ST018.out_index = 0;
 161                         ST018.part_command = 0; // 3-byte commands
 162                         ST018.pass = 0; // data streams into the chip
 163                         switch(ST018.command & 0xFFFFFF)
 164                         {
 165                         case 0x0100: ST018.in_count = 0; break;
 166                         case 0xFF00: ST018.in_count = 0; break;
 167                         default: ST018.waiting4command = true; break;
 168                         }
 169                 }
 170                 else if(ST018.waiting4command)
 171                 {
 172                         // 3-byte commands
 173                         ST018.part_command++;
 174                         ST018.command <<= 8;
 175                         ST018.command |= Byte;
 176                 }
 177         }
 178         // extra parameters
 179         else if (address==0x3802)
 180         {
 181                 ST018.parameters[ST018.in_index] = Byte;
 182                 ST018.in_index++;
 183         }
 184
 185         if (ST018.in_count==ST018.in_index)
 186         {
 187                 // Actually execute the command
 188                 ST018.waiting4command = true;
 189                 ST018.in_index = 0;
 190                 ST018.out_index = 0;
 191                 switch (ST018.command)
 192                 {
 193                 // hardware check?
 194                 case 0x0100:
 195                         ST018.waiting4command = false;
 196                         ST018.pass++;
 197                         if (ST018.pass==1)
 198                         {
 199                                 ST018.in_count = 1;
 200                                 ST018.out_count = 2;
 201
 202                                 // Overload's research
 203                                 ST018.output[0x00] = 0x81;
 204                                 ST018.output[0x01] = 0x81;
 205                         }
 206                         else
 207                         {
 208                                 //ST018.in_count = 1;
 209                                 ST018.out_count = 3;
 210
 211                                 // no reason to change this
 212                                 //ST018.output[0x00] = 0x81;
 213                                 //ST018.output[0x01] = 0x81;
 214                                 ST018.output[0x02] = 0x81;
 215
 216                                 // done processing requests
 217                                 if (ST018.pass==3)
 218                                         ST018.waiting4command = true;
 219                         }
 220                         break;
 221
 222                 // unknown: feels like a security detection
 223                 // format identical to 0x0100
 224                 case 0xFF00:
 225                         ST018.waiting4command = false;
 226                         ST018.pass++;
 227                         if (ST018.pass==1)
 228                         {
 229                                 ST018.in_count = 1;
 230                                 ST018.out_count = 2;
 231
 232                                 // Overload's research
 233                                 ST018.output[0x00] = 0x81;
 234                                 ST018.output[0x01] = 0x81;
 235                         }
 236                         else
 237                         {
 238                                 //ST018.in_count = 1;
 239                                 ST018.out_count = 3;
 240
 241                                 // no reason to change this
 242                                 //ST018.output[0x00] = 0x81;
 243                                 //ST018.output[0x01] = 0x81;
 244                                 ST018.output[0x02] = 0x81;
 245
 246                                 // done processing requests
 247                                 if (ST018.pass==3)
 248                                         ST018.waiting4command = true;
 249                         }
 250                         break;
 251                 }
 252         }
 253 }
 254 }
 255