MSXE6Timer.hh

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/*
 * This class implements a simple timer, used in a TurboR.
 * This is a 16-bit (up) counter running at 255681Hz (3.58MHz / 14).
 * The least significant byte can be read from port 0xE6.
 *     most                                         0xE7.
 * Writing a random value to port 0xE6 resets the counter.
 * Writing to port 0xE7 has no effect.
 */
 
#ifndef MSXE6TIMER_HH
#define MSXE6TIMER_HH
 
#include "MSXDevice.hh"
#include "Clock.hh"
 
namespace openmsx {
 
class MSXE6Timer final : public MSXDevice
{
public:
        explicit MSXE6Timer(const DeviceConfig& config);
 
        void reset(EmuTime::param time) override;
        [[nodiscard]] byte readIO(word port, EmuTime::param time) override;
        void writeIO(word port, byte value, EmuTime::param time) override;
        [[nodiscard]] byte peekIO(word port, EmuTime::param time) const override;
 
        template<typename Archive>
        void serialize(Archive& ar, unsigned version);
 
private:
        Clock<3579545, 14> reference; // (3.58 / 14)MHz
};
 
} // namespace openmsx
 
#endif