SVIPrinterPort.cc

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// $Id:$

#include "SVIPrinterPort.hh"
#include "DummyPrinterPortDevice.hh"
#include "checked_cast.hh"
#include "serialize.hh"
#include "unreachable.hh"
#include <memory>

// Centronics interface
//
// DAT0-DAT7   Printer data write port, output (10H)
// /STB        Printer strobe port,     output (11H)
// BUSY        Printer status port,     input  (12H)

namespace openmsx {

SVIPrinterPort::SVIPrinterPort(const DeviceConfig& config)
        : MSXDevice(config)
        , Connector(MSXDevice::getPluggingController(), "printerport",
                    std::make_unique<DummyPrinterPortDevice>())
{
        data = 255;     // != 0;
        strobe = false; // != true;
        reset(getCurrentTime());
}

void SVIPrinterPort::reset(EmuTime::param time)
{
        writeData(0, time);    // TODO check this
        setStrobe(true, time); // TODO check this
}

byte SVIPrinterPort::readIO(word port, EmuTime::param time)
{
        return peekIO(port, time);
}

byte SVIPrinterPort::peekIO(word /*port*/, EmuTime::param time) const
{
        // bit 1 = status / other bits always 1
        return getPluggedPrintDev().getStatus(time) ? 0xFF : 0xFE;
}

void SVIPrinterPort::writeIO(word port, byte value, EmuTime::param time)
{
        switch (port & 0x01) {
        case 0:
                writeData(value, time);
                break;
        case 1:
                setStrobe(value & 1, time); // bit 0 = strobe
                break;
        default:
                UNREACHABLE;
        }
}

void SVIPrinterPort::setStrobe(bool newStrobe, EmuTime::param time)
{
        if (newStrobe != strobe) {
                strobe = newStrobe;
                getPluggedPrintDev().setStrobe(strobe, time);
        }
}
void SVIPrinterPort::writeData(byte newData, EmuTime::param time)
{
        if (newData != data) {
                data = newData;
                getPluggedPrintDev().writeData(data, time);
        }
}

string_view SVIPrinterPort::getDescription() const
{
        return "Spectravideo SVI-328 Printer port";
}

string_view SVIPrinterPort::getClass() const
{
        return "Printer Port";
}

void SVIPrinterPort::plug(Pluggable& dev, EmuTime::param time)
{
        Connector::plug(dev, time);
        getPluggedPrintDev().writeData(data, time);
        getPluggedPrintDev().setStrobe(strobe, time);
}

PrinterPortDevice& SVIPrinterPort::getPluggedPrintDev() const
{
        return *checked_cast<PrinterPortDevice*>(&getPlugged());
}

template<typename Archive>
void SVIPrinterPort::serialize(Archive& ar, unsigned /*version*/)
{
        ar.template serializeBase<MSXDevice>(*this);
        ar.template serializeBase<Connector>(*this);
        ar.serialize("strobe", strobe);
        ar.serialize("data", data);
        // TODO force writing data to port??
}
INSTANTIATE_SERIALIZE_METHODS(SVIPrinterPort);
REGISTER_MSXDEVICE(SVIPrinterPort, "SVI-328 PrinterPort");

} // namespace openmsx