MSXAudio.cc

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#include "MSXAudio.hh"
#include "Y8950Periphery.hh"
#include "DACSound8U.hh"
#include "StringOp.hh"
#include "serialize.hh"
#include <memory>
 
namespace openmsx {
 
// MSXAudio
 
MSXAudio::MSXAudio(const DeviceConfig& config)
        : MSXDevice(config)
        , y8950(getName(), config,
                config.getChildDataAsInt("sampleram", 256) * 1024,
                getCurrentTime(), *this)
        , dacValue(0x80), dacEnabled(false)
{
        auto type = config.getChildData("type", "philips");
        StringOp::casecmp cmp;
        if (cmp(type, "philips")) {
                dac = std::make_unique<DACSound8U>(
                        getName() + " 8-bit DAC", "MSX-AUDIO 8-bit DAC",
                        config);
        }
        powerUp(getCurrentTime());
}
 
MSXAudio::~MSXAudio()
{
        // delete soon, because PanasonicAudioPeriphery still uses
        // this object in its destructor
        periphery.reset();
}
 
Y8950Periphery& MSXAudio::createPeriphery(const std::string& soundDeviceName)
{
        periphery = Y8950PeripheryFactory::create(
                *this, getDeviceConfig2(), soundDeviceName);
        return *periphery;
}
 
void MSXAudio::powerUp(EmuTime::param time)
{
        y8950.clearRam();
        reset(time);
}
 
void MSXAudio::reset(EmuTime::param time)
{
        y8950.reset(time);
        periphery->reset();
        registerLatch = 0; // TODO check
}
 
byte MSXAudio::readIO(word port, EmuTime::param time)
{
        if ((port & 0xE8) == 0x08) {
                // read DAC
                return 0xFF;
        } else {
                return (port & 1) ? y8950.readReg(registerLatch, time)
                                  : y8950.readStatus(time);
        }
}
 
byte MSXAudio::peekIO(word port, EmuTime::param time) const
{
        if ((port & 0xE8) == 0x08) {
                // read DAC
                return 0xFF; // read always returns 0xFF
        } else {
                return (port & 1) ? y8950.peekReg(registerLatch, time)
                                  : y8950.peekStatus(time);
        }
}
 
void MSXAudio::writeIO(word port, byte value, EmuTime::param time)
{
        if ((port & 0xE8) == 0x08) {
                dacValue = value;
                if (dacEnabled) {
                        assert(dac);
                        dac->writeDAC(dacValue, time);
                }
        } else if ((port & 0x01) == 0) {
                // 0xC0 or 0xC2
                registerLatch = value;
        } else {
                // 0xC1 or 0xC3
                y8950.writeReg(registerLatch, value, time);
        }
}
 
byte MSXAudio::readMem(word address, EmuTime::param time)
{
        return periphery->readMem(address, time);
}
byte MSXAudio::peekMem(word address, EmuTime::param time) const
{
        return periphery->peekMem(address, time);
}
void MSXAudio::writeMem(word address, byte value, EmuTime::param time)
{
        periphery->writeMem(address, value, time);
}
const byte* MSXAudio::getReadCacheLine(word start) const
{
        return periphery->getReadCacheLine(start);
}
byte* MSXAudio::getWriteCacheLine(word start) const
{
        return periphery->getWriteCacheLine(start);
}
 
void MSXAudio::enableDAC(bool enable, EmuTime::param time)
{
        if ((dacEnabled != enable) && dac) {
                dacEnabled = enable;
                byte value = dacEnabled ? dacValue : 0x80;
                dac->writeDAC(value, time);
        }
}
 
template<typename Archive>
void MSXAudio::serialize(Archive& ar, unsigned /*version*/)
{
        ar.serializePolymorphic("periphery", *periphery);
        ar.serialize("Y8950",         y8950,
                     "registerLatch", registerLatch,
                     "dacValue",      dacValue,
                     "dacEnabled",    dacEnabled);
 
        if constexpr (Archive::IS_LOADER) {
                // restore dac status
                if (dacEnabled) {
                        assert(dac);
                        dac->writeDAC(dacValue, getCurrentTime());
                }
        }
}
INSTANTIATE_SERIALIZE_METHODS(MSXAudio);
REGISTER_MSXDEVICE(MSXAudio, "MSX-Audio");
 
} // namespace openmsx