MSXRS232.hh

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#ifndef MSXRS232_HH
#define MSXRS232_HH
 
#include "MSXDevice.hh"
#include "IRQHelper.hh"
#include "RS232Connector.hh"
#include "I8251.hh"
#include "I8254.hh"
#include <memory>
 
namespace openmsx {
 
class Ram;
class Rom;
class BooleanSetting;
 
class MSXRS232 final : public MSXDevice, public RS232Connector
{
public:
        explicit MSXRS232(const DeviceConfig& config);
        ~MSXRS232() override;
 
        void powerUp(EmuTime::param time) override;
        void reset(EmuTime::param time) override;
        [[nodiscard]] byte readIO(word port, EmuTime::param time) override;
        [[nodiscard]] byte peekIO(word port, EmuTime::param time) const override;
        void writeIO(word port, byte value, EmuTime::param time) override;
        [[nodiscard]] byte readMem(word address, EmuTime::param time) override;
        // TODO: implement peekMem, because the default isn't OK anymore
        [[nodiscard]] const byte *getReadCacheLine(word start) const override;
        void writeMem(word address, byte value, EmuTime::param time) override;
        [[nodiscard]] byte* getWriteCacheLine(word start) const override;
        [[nodiscard]] bool allowUnaligned() const override;
 
        // RS232Connector  (input)
        void setDataBits(DataBits bits) override;
        void setStopBits(StopBits bits) override;
        void setParityBit(bool enable, ParityBit parity) override;
        void recvByte(byte value, EmuTime::param time) override;
        [[nodiscard]] bool ready() override;
        [[nodiscard]] bool acceptsData() override;
 
        template<typename Archive>
        void serialize(Archive& ar, unsigned version);
 
private:
        [[nodiscard]] byte readIOImpl(word port, EmuTime::param time);
        void writeIOImpl(word port, byte value, EmuTime::param time);
 
        [[nodiscard]] byte readStatus(EmuTime::param time);
        void setIRQMask(byte value);
        void setRxRDYIRQ(bool status);
        void enableRxRDYIRQ(bool enabled);
 
        struct Counter0 final : ClockPinListener {
                void signal(ClockPin& pin, EmuTime::param time) override;
                void signalPosEdge(ClockPin& pin, EmuTime::param time) override;
        } cntr0; // counter 0 rx clock pin
 
        struct Counter1 final : ClockPinListener {
                void signal(ClockPin& pin, EmuTime::param time) override;
                void signalPosEdge(ClockPin& pin, EmuTime::param time) override;
        } cntr1; // counter 1 tx clock pin
 
        I8254 i8254;
 
        struct Interface final : I8251Interface {
                void setRxRDY(bool status, EmuTime::param time) override;
                void setDTR(bool status, EmuTime::param time) override;
                void setRTS(bool status, EmuTime::param time) override;
                [[nodiscard]] bool getDSR(EmuTime::param time) override;
                [[nodiscard]] bool getCTS(EmuTime::param time) override;
                void setDataBits(DataBits bits) override;
                void setStopBits(StopBits bits) override;
                void setParityBit(bool enable, ParityBit parity) override;
                void recvByte(byte value, EmuTime::param time) override;
                void signal(EmuTime::param time) override;
        } interface;
 
        I8251 i8251;
        const std::unique_ptr<Rom> rom; // can be nullptr
        const std::unique_ptr<Ram> ram; // can be nullptr
 
        IRQHelper rxrdyIRQ;
        bool rxrdyIRQlatch = false;
        bool rxrdyIRQenabled = false;
 
        const bool hasMemoryBasedIo;
        bool ioAccessEnabled;
 
        const std::unique_ptr<BooleanSetting> switchSetting; // can be nullptr
};
SERIALIZE_CLASS_VERSION(MSXRS232, 2);
 
 
} // namespace openmsx
 
#endif