DACSound16S.cc

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#include "DACSound16S.hh"
#include "DeviceConfig.hh"
#include "MSXMotherBoard.hh"
#include "DynamicClock.hh"
#include "serialize.hh"

namespace openmsx {

DACSound16S::DACSound16S(string_ref name, string_ref desc,
                         const DeviceConfig& config)
        : SoundDevice(config.getMotherBoard().getMSXMixer(), name, desc, 1)
        , lastWrittenValue(0)
{
        registerSound(config);
}

DACSound16S::~DACSound16S()
{
        unregisterSound();
}

void DACSound16S::setOutputRate(unsigned sampleRate)
{
        setInputRate(sampleRate);
}

void DACSound16S::reset(EmuTime::param time)
{
        writeDAC(0, time);
}

void DACSound16S::writeDAC(short value, EmuTime::param time)
{
        int delta = value - lastWrittenValue;
        if (delta == 0) return;
        lastWrittenValue = value;

        BlipBuffer::TimeIndex t;
        getHostSampleClock().getTicksTill(time, t);
        blip.addDelta(t, delta);
}

void DACSound16S::generateChannels(int** bufs, unsigned num)
{
        // Note: readSamples() replaces the values in the buffer. It should add
        //       to the existing values in the buffer. But because there is only
        //       one channel this doesn't matter (buffer contains all zeros).
        if (!blip.readSamples<1>(bufs[0], num)) {
                bufs[0] = nullptr;
        }
}

bool DACSound16S::updateBuffer(unsigned length, int* buffer,
                               EmuTime::param /*time*/)
{
        return mixChannels(buffer, length);
}


template<typename Archive>
void DACSound16S::serialize(Archive& ar, unsigned /*version*/)
{
        // Note: It's ok to NOT serialize a DAC object if you call the
        //       writeDAC() method in some other way during de-serialization.
        //       This is for example done in MSXPPI/KeyClick.
        short lastValue = lastWrittenValue;
        ar.serialize("lastValue", lastValue);
        if (ar.isLoader()) {
                writeDAC(lastValue, getHostSampleClock().getTime());
        }
}
INSTANTIATE_SERIALIZE_METHODS(DACSound16S);

} // namespace openmsx