Files

326 lines
9.9 KiB
C
Executable File

/*****************************************************************************
** $Source: /cygdrive/d/Private/_SVNROOT/bluemsx/blueMSX/Src/Memory/romMapperSCCplus.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 "romMapperSCCplus.h"
#include "MediaDb.h"
#include "SlotManager.h"
#include "DeviceManager.h"
#include "SCC.h"
#include "Board.h"
#include "SaveState.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
typedef struct {
int deviceHandle;
UInt8 romData[0x22000];
int slot;
int sslot;
int startPage;
UInt8 modeRegister;
UInt8 mapperMask;
int isMapped[4];
int isRamSegment[4];
int romMapper[4];
SccType sccType;
SccMode sccMode;
SCC* scc;
} RomMapperSCCplus;
static void saveState(RomMapperSCCplus* rm)
{
SaveState* state = saveStateOpenForWrite("mapperSCCplus");
char tag[16];
int i;
for (i = 0; i < 4; i++) {
sprintf(tag, "romMapper%d", i);
saveStateSet(state, tag, rm->romMapper[i]);
sprintf(tag, "isRamSegment%d", i);
saveStateSet(state, tag, rm->isRamSegment[i]);
sprintf(tag, "isMapped%d", i);
saveStateSet(state, tag, rm->isMapped[i]);
}
saveStateSet(state, "modeRegister", rm->modeRegister);
saveStateSet(state, "sccMode", rm->sccMode);
saveStateSetBuffer(state, "romData", rm->romData, sizeof(rm->romData));
saveStateClose(state);
sccSaveState(rm->scc);
}
static void loadState(RomMapperSCCplus* rm)
{
SaveState* state = saveStateOpenForRead("mapperSCCplus");
char tag[16];
int bank;
int i;
for (i = 0; i < 4; i++) {
sprintf(tag, "romMapper%d", i);
rm->romMapper[i] = saveStateGet(state, tag, 0);
sprintf(tag, "isRamSegment%d", i);
rm->isRamSegment[i] = saveStateGet(state, tag, 0);
sprintf(tag, "isMapped%d", i);
rm->isMapped[i] = saveStateGet(state, tag, 0);
}
rm->modeRegister = (UInt8)saveStateGet(state, "modeRegister", 0);
rm->sccMode = saveStateGet(state, "sccMode", 0);
saveStateGetBuffer(state, "romData", rm->romData, sizeof(rm->romData));
saveStateClose(state);
sccLoadState(rm->scc);
for (bank = 0; bank < 4; bank++) {
if (rm->isMapped[bank]) {
slotMapPage(rm->slot, rm->sslot, rm->startPage + bank, rm->romData + 0x2000 * rm->romMapper[bank], 1, 0);
}
else {
slotMapPage(rm->slot, rm->sslot, rm->startPage + bank, rm->romData + 0x20000, 1, 0);
}
}
if (rm->sccMode == SCC_PLUS) {
slotMapPage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 0, 0);
}
else if ((rm->sccMode = SCC_COMPATIBLE)) {
slotMapPage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 0, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 1, 0);
}
else {
slotMapPage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 1, 0);
}
}
static void destroy(RomMapperSCCplus* rm)
{
slotUnregister(rm->slot, rm->sslot, rm->startPage);
deviceManagerUnregister(rm->deviceHandle);
sccDestroy(rm->scc);
free(rm);
}
static void reset(RomMapperSCCplus* rm)
{
sccReset(rm->scc);
}
static UInt8 read(RomMapperSCCplus* rm, UInt16 address)
{
int bank;
address += 0x4000;
if (rm->sccMode == SCC_COMPATIBLE && address >= 0x9800 && address < 0xa000) {
return sccRead(rm->scc, (UInt8)(address & 0xff));
}
if (rm->sccMode == SCC_PLUS && address >= 0xb800 && address < 0xc000) {
return sccRead(rm->scc, (UInt8)(address & 0xff));
}
bank = (address - 0x4000) >> 13;
if (rm->isMapped[bank]) {
return rm->romData[0x2000 * (rm->romMapper[bank] & rm->mapperMask) + (address & 0x1fff)];
}
return 0xff;
}
static UInt8 peek(RomMapperSCCplus* rm, UInt16 address)
{
int bank;
address += 0x4000;
if (rm->sccMode == SCC_COMPATIBLE && address >= 0x9800 && address < 0xa000) {
return sccPeek(rm->scc, (UInt8)(address & 0xff));
}
if (rm->sccMode == SCC_PLUS && address >= 0xb800 && address < 0xc000) {
return sccPeek(rm->scc, (UInt8)(address & 0xff));
}
bank = (address - 0x4000) >> 13;
if (rm->isMapped[bank]) {
return rm->romData[0x2000 * (rm->romMapper[bank] & rm->mapperMask) + (address & 0x1fff)];
}
return 0xff;
}
static void updateEnable(RomMapperSCCplus* rm)
{
if ((rm->modeRegister & 0x20) && (rm->romMapper[3] & 0x80)) {
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 1, 0);
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 0, 0);
sccSetMode(rm->scc, SCC_PLUS);
rm->sccMode = SCC_PLUS;
}
else if (!(rm->modeRegister & 0x20) && (rm->romMapper[2] & 0x3f) == 0x3f) {
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 0, 0);
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 1, 0);
sccSetMode(rm->scc, SCC_COMPATIBLE);
rm->sccMode = SCC_COMPATIBLE;
}
else {
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 2, NULL, 1, 0);
slotUpdatePage(rm->slot, rm->sslot, rm->startPage + 3, NULL, 1, 0);
rm->sccMode = SCC_NONE;
}
}
static void write(RomMapperSCCplus* rm, UInt16 address, UInt8 value)
{
int bank;
address += 0x4000;
if (address < 0x4000 && address >= 0xc000) {
return;
}
if ((address | 1) == 0xbfff) {
rm->modeRegister = value;
rm->isRamSegment[0] = (value & 0x10) | (value & 0x01);
rm->isRamSegment[1] = (value & 0x10) | (value & 0x02);
rm->isRamSegment[2] = (value & 0x10) | ((value & 0x24) == 0x24);
rm->isRamSegment[3] = (value & 0x10);
updateEnable(rm);
return;
}
bank = (address - 0x4000) >> 13;
if (rm->isRamSegment[bank]) {
if (rm->isMapped[bank]) {
rm->romData[0x2000 * (rm->romMapper[bank] & rm->mapperMask) + (address & 0x1fff)] = value;
}
return;
}
if ((address & 0x1800) == 0x1000) {
rm->romMapper[bank] = value;
value &= rm->mapperMask;
rm->isMapped[bank] = (value >= 8 && rm->sccType != SCC_SNATCHER) ||
(value < 8 && rm->sccType != SCC_SDSNATCHER);
if (rm->isMapped[bank]) {
slotMapPage(rm->slot, rm->sslot, rm->startPage + bank, rm->romData + 0x2000 * value, 1, 0);
}
else {
slotMapPage(rm->slot, rm->sslot, rm->startPage + bank, rm->romData + 0x20000, 1, 0);
}
updateEnable(rm);
return;
}
if (rm->sccMode == SCC_COMPATIBLE && address >= 0x9800 && address < 0xa000) {
sccWrite(rm->scc, address & 0xff, value);
}
else if (rm->sccMode == SCC_PLUS && address >= 0xb800 && address < 0xc000) {
sccWrite(rm->scc, address & 0xff, value);
}
}
int romMapperSCCplusCreate(const char* filename, UInt8* romData,
int size, int slot, int sslot, int startPage, SccType sccType)
{
DeviceCallbacks callbacks = { destroy, reset, saveState, loadState };
RomMapperSCCplus* rm;
rm = malloc(sizeof(RomMapperSCCplus));
rm->deviceHandle = deviceManagerRegister(ROM_SCCEXTENDED, &callbacks, rm);
slotRegister(slot, sslot, startPage, 4, read, peek, write, destroy, rm);
memset(rm->romData, 0xff, 0x22000);
if (romData) {
if (size > 0x20000) {
size = 0x20000;
}
memcpy(rm->romData, romData, size);
}
rm->slot = slot;
rm->sslot = sslot;
rm->startPage = startPage;
rm->modeRegister = sccType == SCCP_EXTENDED ? 0x20 : 0;
rm->isRamSegment[0] = 0;
rm->isRamSegment[1] = 0;
rm->isRamSegment[2] = 0;
rm->isRamSegment[3] = 0;
rm->isMapped[0] = sccType != SCC_SDSNATCHER;
rm->isMapped[1] = sccType != SCC_SDSNATCHER;
rm->isMapped[2] = sccType != SCC_SDSNATCHER;
rm->isMapped[3] = sccType != SCC_SDSNATCHER;
rm->mapperMask = sccType == SCC_MIRRORED ? 0x07 : 0x0f;
rm->scc = sccCreate(boardGetMixer());
rm->sccType = sccType;
rm->sccMode = SCC_NONE;
rm->romMapper[0] = 0;
rm->romMapper[1] = 1;
rm->romMapper[2] = 2;
rm->romMapper[3] = 3;
if (sccType != SCC_SDSNATCHER) {
slotMapPage(rm->slot, rm->sslot, rm->startPage, rm->romData + 0x0000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 1, rm->romData + 0x2000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 2, rm->romData + 0x4000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 3, rm->romData + 0x6000, 1, 0);
}
else {
slotMapPage(rm->slot, rm->sslot, rm->startPage, rm->romData + 0x20000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 1, rm->romData + 0x20000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 2, rm->romData + 0x20000, 1, 0);
slotMapPage(rm->slot, rm->sslot, rm->startPage + 3, rm->romData + 0x20000, 1, 0);
}
return 1;
}