Files

161 lines
4.3 KiB
C
Executable File

/*****************************************************************************
** $Source: /cygdrive/d/Private/_SVNROOT/bluemsx/blueMSX/Src/Memory/romMapperPAC.c,v $
**
** $Revision: 1.7 $
**
** $Date: 2008-03-30 18:38:44 $
**
** More info: http://www.bluemsx.com
**
** Copyright (C) 2003-2006 Daniel Vik
**
** 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 2 of the License, or
** (at your option) 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, write to the Free Software
** Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**
******************************************************************************
*/
#include "romMapperPAC.h"
#include "MediaDb.h"
#include "IoPort.h"
#include "SlotManager.h"
#include "DeviceManager.h"
#include "SaveState.h"
#include "sramLoader.h"
#include <stdlib.h>
#include <string.h>
static char pacHeader[] = "PAC2 BACKUP DATA";
typedef struct {
int deviceHandle;
UInt8 reg1ffe;
UInt8 reg1fff;
UInt8 sram[0x2000];
char sramFilename[512];
int slot;
int sslot;
int startPage;
int sramEnabled;
} RomMapperPAC;
static void saveState(RomMapperPAC* rm)
{
SaveState* state = saveStateOpenForWrite("mapperPAC");
saveStateSetBuffer(state, "sram", rm->sram, sizeof(rm->sram));
saveStateClose(state);
}
static void loadState(RomMapperPAC* rm)
{
SaveState* state = saveStateOpenForRead("mapperPAC");
saveStateGetBuffer(state, "sram", rm->sram, sizeof(rm->sram));
saveStateClose(state);
rm->sramEnabled = rm->sram[0x1ffe] == 0x4d && rm->sram[0x1fff] == 0x69;
if (rm->sramEnabled) {
slotMapPage(rm->slot, rm->sslot, rm->startPage, rm->sram, 1, 0);
}
else {
slotUnmapPage(rm->slot, rm->sslot, rm->startPage);
}
}
static void destroy(RomMapperPAC* rm)
{
sramSave(rm->sramFilename, rm->sram, 0x1ffe, pacHeader, strlen(pacHeader));
slotUnregister(rm->slot, rm->sslot, rm->startPage);
deviceManagerUnregister(rm->deviceHandle);
free(rm);
}
static UInt8 read(RomMapperPAC* rm, UInt16 address)
{
switch (address & 0x3fff) {
case 0x1ffe:
return rm->sram[0x1ffe];
case 0x1fff:
return rm->sram[0x1fff];
}
return 0xff;
}
static void write(RomMapperPAC* rm, UInt16 address, UInt8 value)
{
int update = 0;
address &= 0x3fff;
switch (address) {
case 0x1ffe:
rm->sram[0x1ffe] = value;
rm->sramEnabled = rm->sram[0x1ffe] == 0x4d && rm->sram[0x1fff] == 0x69;
update = 1;
break;
case 0x1fff:
rm->sram[0x1fff] = value;
rm->sramEnabled = rm->sram[0x1ffe] == 0x4d && rm->sram[0x1fff] == 0x69;
update = 1;
break;
default:
if (rm->sramEnabled && address < 0x1ffe) {
rm->sram[address] = value;
}
break;
}
if (update) {
if (rm->sramEnabled) {
slotMapPage(rm->slot, rm->sslot, rm->startPage, rm->sram, 1, 0);
}
else {
slotMapPage(rm->slot, rm->sslot, rm->startPage, NULL, 0, 0);
}
}
}
int romMapperPACCreate(const char* filename, UInt8* romData,
int size, int slot, int sslot, int startPage)
{
DeviceCallbacks callbacks = { destroy, NULL, saveState, loadState };
RomMapperPAC* rm;
rm = malloc(sizeof(RomMapperPAC));
rm->deviceHandle = deviceManagerRegister(ROM_PAC, &callbacks, rm);
slotRegister(slot, sslot, startPage, 2, read, read, write, destroy, rm);
memset(rm->sram, 0xff, 0x2000);
rm->slot = slot;
rm->sslot = sslot;
rm->startPage = startPage;
rm->sramEnabled = 0;
strcpy(rm->sramFilename, sramCreateFilename(filename));
sramLoad(rm->sramFilename, rm->sram, 0x1ffe, pacHeader, strlen(pacHeader));
slotMapPage(rm->slot, rm->sslot, rm->startPage, NULL, 0, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 1, NULL, 0, 0);
return 1;
}