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◆ main openmsx / src / memory / RomMSXDOS2.cc
1.3 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
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#include "RomMSXDOS2.hh"
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#include "CacheLine.hh"
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#include "MSXException.hh"
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#include "one_of.hh"
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#include "unreachable.hh"
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namespace openmsx {
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RomMSXDOS2::RomMSXDOS2(const DeviceConfig& config, Rom&& rom_)
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	: Rom16kBBlocks(config, std::move(rom_))
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	, range(rom[0x94])
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{
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	if (range != one_of(0x00, 0x60, 0x7f)) {
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		throw MSXException(
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			"Invalid rom with for MSXDOS2 mapper: unsupported range 0x",
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			hex_string<2>(range));
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	}
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	reset(EmuTime::dummy());
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}
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void RomMSXDOS2::reset(EmuTime /*time*/)
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{
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	setUnmapped(0);
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	setRom(1, 0);
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	setUnmapped(2);
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	setUnmapped(3);
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}
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void RomMSXDOS2::writeMem(uint16_t address, byte value, EmuTime /*time*/)
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{
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	switch (range) {
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	case 0x00:
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		if (address != 0x7ff0) return;
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		break;
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	case 0x60:
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		if ((address & 0xf000) != 0x6000) return;
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		break;
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	case 0x7f:
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		if (address != 0x7ffe) return;
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		break;
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	default:
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		UNREACHABLE;
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	}
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	setRom(1, value);
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}
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byte* RomMSXDOS2::getWriteCacheLine(uint16_t address)
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{
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	switch (range) {
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	case 0x00:
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		if (address == (0x7ff0 & CacheLine::HIGH)) return nullptr;
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		break;
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	case 0x60:
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		if ((address & 0xf000) == 0x6000) return nullptr;
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		break;
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	case 0x7f:
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		if (address == (0x7ffe & CacheLine::HIGH)) return nullptr;
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		break;
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	default:
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		UNREACHABLE;
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	}
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	return unmappedWrite.data();
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}
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REGISTER_MSXDEVICE(RomMSXDOS2, "RomMSXDOS2");
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} // namespace openmsx