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54 lines
950 B
C++
54 lines
950 B
C++
#pragma once
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#include "stdafx.h"
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#include "CPU.h"
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#include "PPU.h"
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#include "Snapshotable.h"
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enum class A12StateChange
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{
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None = 0,
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Rise = 1,
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Fall = 2
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};
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class A12Watcher : public Snapshotable
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{
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private:
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uint32_t _lastCycle = 0;
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uint32_t _cyclesDown = 0;
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public:
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void StreamState(bool saving) override
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{
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Stream(_lastCycle, _cyclesDown);
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}
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A12StateChange UpdateVramAddress(uint16_t addr)
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{
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A12StateChange result = A12StateChange::None;
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uint32_t cycle = PPU::GetFrameCycle();
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if((addr & 0x1000) == 0) {
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if(_cyclesDown == 0) {
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_cyclesDown = 1;
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} else {
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if(_lastCycle > cycle) {
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//We changed frames
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_cyclesDown += (89342 - _lastCycle) + cycle;
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} else {
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_cyclesDown += (cycle - _lastCycle);
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}
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}
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result = A12StateChange::Fall;
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} else if(addr & 0x1000) {
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if(_cyclesDown > 8) {
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result = A12StateChange::Rise;
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}
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_cyclesDown = 0;
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}
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_lastCycle = cycle;
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return result;
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}
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}; |