KonamiUltimateCollection.cc

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#include "KonamiUltimateCollection.hh"
#include "narrow.hh"
#include "ranges.hh"
#include "serialize.hh"
#include <array>
 
/******************************************************************************
 * DOCUMENTATION AS PROVIDED BY MANUEL PAZOS, WHO DEVELOPED THE CARTRIDGE     *
 ******************************************************************************
 
   Konami Ultimate Collection shares some features of MegaFlashROM SCC+ SD
   It uses the same flashROM, SCC/SCC+, Konami and Konami SCC mappers, etc.
 
[OFFSET REGISTER (#7FFE)]
7-0: Bank offset
 
[MAPPER REGISTER (#7FFF)]
7     A21 \
6     A20 / FlashROM address lines to switch 2 MB banks.
5     Mapper mode  :   Select Konami mapper (0=SCC or 1=normal). [1]
4     Flash write enable
3     Disable #4000-#5FFF mapper in Konami mode, Enable DAC (works like the DAC of Synthesizer or Majutsushi)
2     Disable mapper register
1     Disable mapper (bank switching)
0     no function anymore (was mapper limits)
 
[1] bit 5 only changes the address range of the mapper (Konami or Konami SCC)
but the SCC is always available.  This feature is inherited from MFC SCC+ subslot
mode because all subslots share the same mapper type. So to make Konami
combinations (i.e.: Konami ROM with Konami SCC ROM) a "common mapper" is needed
and the SCC must be available. So I made a "Konami mapper" with SCC.  In fact,
all Konami and Konami SCC ROMs should work with "Konami" mapper in KUC.
 
******************************************************************************/
 
namespace openmsx {
 
KonamiUltimateCollection::KonamiUltimateCollection(
                const DeviceConfig& config, Rom&& rom_)
        : MSXRom(config, std::move(rom_))
        , flash(rom, AmdFlashChip::M29W640GB, {}, config)
        , scc("KUC SCC", config, getCurrentTime(), SCC::Mode::Compatible)
        , dac("KUC DAC", "Konami Ultimate Collection DAC", config)
{
        powerUp(getCurrentTime());
}
 
void KonamiUltimateCollection::powerUp(EmuTime::param time)
{
        scc.powerUp(time);
        reset(time);
}
 
void KonamiUltimateCollection::reset(EmuTime::param time)
{
        mapperReg = 0;
        offsetReg = 0;
        sccMode = 0;
        ranges::iota(bankRegs, byte(0));
 
        scc.reset(time);
        dac.reset(time);
 
        invalidateDeviceRWCache(); // flush all to be sure
}
 
unsigned KonamiUltimateCollection::getFlashAddr(unsigned addr) const
{
        unsigned page8kB = (addr >> 13) - 2;
        if (page8kB >= 4) return unsigned(-1); // outside [0x4000, 0xBFFF]
 
        byte bank = bankRegs[page8kB] + offsetReg; // wrap at 8 bit
        return ((mapperReg & 0xC0) << (21 - 6)) | (bank << 13) | (addr & 0x1FFF);
}
 
bool KonamiUltimateCollection::isSCCAccess(word addr) const
{
        if (sccMode & 0x10) return false;
 
        if (addr & 0x0100) {
                // Address bit 8 must be zero, this is different from a real
                // SCC/SCC+. According to Manuel Pazos this is a leftover from
                // an earlier version that had 2 SCCs: the SCC on the left or
                // right channel reacts when address bit 8 is respectively 0/1.
                return false;
        }
 
        if (sccMode & 0x20) {
                // SCC+   range: 0xB800..0xBFFF,  excluding 0xBFFE-0xBFFF
                return  (bankRegs[3] & 0x80)          && (0xB800 <= addr) && (addr < 0xBFFE);
        } else {
                // SCC    range: 0x9800..0x9FFF,  excluding 0x9FFE-0x9FFF
                return ((bankRegs[2] & 0x3F) == 0x3F) && (0x9800 <= addr) && (addr < 0x9FFE);
        }
}
 
byte KonamiUltimateCollection::readMem(word addr, EmuTime::param time)
{
        if (isSCCAccess(addr)) {
                return scc.readMem(narrow_cast<uint8_t>(addr & 0xFF), time);
        }
 
        unsigned flashAddr = getFlashAddr(addr);
        return (flashAddr != unsigned(-1))
                ? flash.read(flashAddr)
                : 0xFF; // unmapped read
}
 
byte KonamiUltimateCollection::peekMem(word addr, EmuTime::param time) const
{
        if (isSCCAccess(addr)) {
                return scc.peekMem(narrow_cast<uint8_t>(addr & 0xFF), time);
        }
 
        unsigned flashAddr = getFlashAddr(addr);
        return (flashAddr != unsigned(-1))
                ? flash.peek(flashAddr)
                : 0xFF; // unmapped read
}
 
const byte* KonamiUltimateCollection::getReadCacheLine(word addr) const
{
        if (isSCCAccess(addr)) return nullptr;
 
        unsigned flashAddr = getFlashAddr(addr);
        return (flashAddr != unsigned(-1))
                ? flash.getReadCacheLine(flashAddr)
                : unmappedRead.data();
}
 
void KonamiUltimateCollection::writeMem(word addr, byte value, EmuTime::param time)
{
        unsigned page8kB = (addr >> 13) - 2;
        if (page8kB >= 4) return; // outside [0x4000, 0xBFFF]
 
        // There are several overlapping functional regions in the address
        // space. A single write can trigger behaviour in multiple regions. In
        // other words there's no priority amongst the regions where a higher
        // priority region blocks the write from the lower priority regions.
        // This only goes for places where the flash is 'seen', so not for the
        // SCC registers
 
        if (isSCCAccess(addr)) {
                scc.writeMem(narrow_cast<uint8_t>(addr & 0xFF), value, time);
                return; // write to SCC blocks write to other functions
        }
 
        // address is calculated before writes to other regions take effect
        unsigned flashAddr = getFlashAddr(addr);
 
        // Mapper and offset registers
        if (isMapperRegisterEnabled()) {
                if (addr == 0x7FFF) {
                        mapperReg = value;
                } else if (addr == 0x7FFE) {
                        offsetReg = value;
                }
                invalidateDeviceRCache(); // flush all to be sure
        }
 
 
        // DAC
        if (isBank0Disabled() && (addr < 0x6000) && ((addr & 0x0010) == 0)) {
                dac.writeDAC(value, time);
        }
 
        if (areBankRegsEnabled()) {
                // Bank-switching
                if (isKonamiSCCmode()) {
                        // Konami-SCC
                        if ((addr & 0x1800) == 0x1000) {
                                // [0x5000,0x57FF] [0x7000,0x77FF]
                                // [0x9000,0x97FF] [0xB000,0xB7FF]
                                // Masking of the mapper bits is done on write
                                bankRegs[page8kB] = value;
                                invalidateDeviceRCache(0x4000 + 0x2000 * page8kB, 0x2000);
                        }
                } else {
                        // Konami
                        if (isBank0Disabled() && (addr < 0x6000)) {
                                // Switching 0x4000-0x5FFF disabled (only Konami mode).
                        } else {
                                // [0x5000,0x57FF] asymmetric!!!
                                // [0x6000,0x7FFF] [0x8000,0x9FFF] [0xA000,0xBFFF]
                                if (!((addr < 0x5000) || ((0x5800 <= addr) && (addr < 0x6000)))) {
                                        // Masking of the mapper bits is done on write
                                        bankRegs[page8kB] = value;
                                        invalidateDeviceRCache(0x4000 + 0x2000 * page8kB, 0x2000);
                                }
                        }
                }
 
                // SCC mode register
                if ((addr & 0xFFFE) == 0xBFFE) {
                        sccMode = value;
                        scc.setMode((value & 0x20) ? SCC::Mode::Plus
                                                   : SCC::Mode::Compatible);
                        invalidateDeviceRCache(0x9800, 0x800);
                        invalidateDeviceRCache(0xB800, 0x800);
                }
        }
 
        if ((flashAddr != unsigned(-1)) && isFlashRomWriteEnabled()) {
                flash.write(flashAddr, value);
        }
}
 
byte* KonamiUltimateCollection::getWriteCacheLine(word addr)
{
        return ((0x4000 <= addr) && (addr < 0xC000))
               ? nullptr        // [0x4000,0xBFFF] isn't cacheable
               : unmappedWrite.data();
}
 
template<typename Archive>
void KonamiUltimateCollection::serialize(Archive& ar, unsigned /*version*/)
{
        // skip MSXRom base class
        ar.template serializeBase<MSXDevice>(*this);
 
        ar.serialize("flash",     flash,
                     "scc",       scc,
                     "DAC",       dac,
                     "mapperReg", mapperReg,
                     "offsetReg", offsetReg,
                     "sccMode",   sccMode,
                     "bankRegs",  bankRegs);
}
INSTANTIATE_SERIALIZE_METHODS(KonamiUltimateCollection);
REGISTER_MSXDEVICE(KonamiUltimateCollection, "KonamiUltimateCollection");
 
} // namespace openmsx