OXYGENHUB
◆ main openmsx / src / video / v9990 / V9990VRAM.cc
1.3 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
e8555c89 Andy McCall 1 
#include "V9990.hh"
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#include "V9990VRAM.hh"
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#include "serialize.hh"
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#include <algorithm>
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namespace openmsx {
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V9990VRAM::V9990VRAM(V9990& vdp_, EmuTime /*time*/)
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	: vdp(vdp_)
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	, data(vdp.getDeviceConfig2(), vdp.getName() + " VRAM",
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	       "V9990 Video RAM", VRAM_SIZE)
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{
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}
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void V9990VRAM::clear()
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{
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	// Initialize memory. Alternate 0x00/0xff every 512 bytes.
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	std::span s = data.getWriteBackdoor();
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	assert((s.size() % 1024) == 0);
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	while (!s.empty()) {
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		std::ranges::fill(s.subspan(  0, 512), 0x00);
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		std::ranges::fill(s.subspan(512, 512), 0xff);
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		s = s.subspan(1024);
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	}
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}
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unsigned V9990VRAM::mapAddress(unsigned address) const
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{
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	address &= 0x7FFFF; // change to assert?
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	switch (vdp.getDisplayMode()) {
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	case V9990DisplayMode::P1:
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		return transformP1(address);
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	case V9990DisplayMode::P2:
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		return transformP2(address);
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	default /* Bx */:
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		return transformBx(address);
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	}
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}
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uint8_t V9990VRAM::readVRAMCPU(unsigned address, EmuTime time)
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{
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	// note: used for both normal and debug read
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	sync(time);
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	return data[mapAddress(address)];
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}
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void V9990VRAM::writeVRAMCPU(unsigned address, uint8_t value, EmuTime time)
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{
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	sync(time);
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	data.write(mapAddress(address), value);
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}
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template<typename Archive>
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void V9990VRAM::serialize(Archive& ar, unsigned /*version*/)
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{
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	ar.serialize("data", data);
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}
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INSTANTIATE_SERIALIZE_METHODS(V9990VRAM);
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} // namespace openmsx