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◆ main openmsx / src / MSXDeviceSwitch.cc
1.9 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
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#include "MSXDeviceSwitch.hh"
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#include "MSXCPUInterface.hh"
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#include "MSXException.hh"
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#include "MSXSwitchedDevice.hh"
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#include "serialize.hh"
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#include <algorithm>
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#include <cassert>
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namespace openmsx {
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MSXDeviceSwitch::MSXDeviceSwitch(const DeviceConfig& config)
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	: MSXDevice(config)
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{
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	std::ranges::fill(devices, nullptr);
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	reset(EmuTime::dummy());
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}
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MSXDeviceSwitch::~MSXDeviceSwitch()
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{
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	// all devices must be unregistered
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	assert(std::ranges::all_of(devices, [](auto* dev) { return dev == nullptr; }));
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	assert(count == 0);
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}
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void MSXDeviceSwitch::registerDevice(byte id, MSXSwitchedDevice* device)
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{
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	if (devices[id]) {
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		// TODO implement multiplexing
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		throw MSXException(
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			"Already have a switched device with id ", int(id));
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	}
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	devices[id] = device;
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	if (count == 0) {
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		getCPUInterface().register_IO_InOut_range(0x40, 16, this);
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	}
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	++count;
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}
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void MSXDeviceSwitch::unregisterDevice(byte id)
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{
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	--count;
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	if (count == 0) {
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		getCPUInterface().unregister_IO_InOut_range(0x40, 16, this);
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	}
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	assert(devices[id]);
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	devices[id] = nullptr;
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}
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void MSXDeviceSwitch::reset(EmuTime /*time*/)
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{
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	selected = 0;
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}
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byte MSXDeviceSwitch::readIO(uint16_t port, EmuTime time)
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{
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	if (devices[selected]) {
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		return devices[selected]->readSwitchedIO(port, time);
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	} else {
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		return 0xFF;
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	}
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}
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byte MSXDeviceSwitch::peekIO(uint16_t port, EmuTime time) const
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{
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	if (devices[selected]) {
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		return devices[selected]->peekSwitchedIO(port, time);
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	} else {
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		return 0xFF;
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	}
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}
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void MSXDeviceSwitch::writeIO(uint16_t port, byte value, EmuTime time)
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{
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	if ((port & 0x0F) == 0x00) {
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		selected = value;
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	} else if (devices[selected]) {
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		devices[selected]->writeSwitchedIO(port, value, time);
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	} else {
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		// ignore
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	}
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}
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template<typename Archive>
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void MSXDeviceSwitch::serialize(Archive& ar, unsigned /*version*/)
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{
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	ar.template serializeBase<MSXDevice>(*this);
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	ar.serialize("selected", selected);
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}
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INSTANTIATE_SERIALIZE_METHODS(MSXDeviceSwitch);
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} // namespace openmsx