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90 lines
2.3 KiB
C++
90 lines
2.3 KiB
C++
#pragma once
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#include "stdafx.h"
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#include "BaseMapper.h"
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#include "VrcIrq.h"
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//incomplete - missing audio
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class VRC7 : public BaseMapper
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{
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private:
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VrcIrq _irq;
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uint8_t _controlFlags;
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uint8_t _chrRegisters[8];
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void UpdatePrgRamAccess()
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{
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SetCpuMemoryMapping(0x6000, 0x7FFF, 0, HasBattery() ? PrgMemoryType::SaveRam : PrgMemoryType::WorkRam, (_controlFlags & 0x80) ? MemoryAccessType::ReadWrite : MemoryAccessType::NoAccess);
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}
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protected:
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virtual uint16_t GetPRGPageSize() { return 0x2000; }
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virtual uint16_t GetCHRPageSize() { return 0x0400; }
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void InitMapper()
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{
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_irq.Reset();
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_controlFlags = 0;
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memset(_chrRegisters, 0, sizeof(_chrRegisters));
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SelectPRGPage(3, -1);
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}
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virtual void StreamState(bool saving)
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{
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BaseMapper::StreamState(saving);
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SnapshotInfo irq{ &_irq };
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ArrayInfo<uint8_t> chrRegisters = { _chrRegisters, 8 };
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Stream(_controlFlags, chrRegisters, irq);
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if(!saving) {
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UpdatePrgRamAccess();
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}
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}
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void ProcessCpuClock()
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{
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_irq.ProcessCpuClock();
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}
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void UpdateState()
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{
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switch(_controlFlags & 0x03) {
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case 0: SetMirroringType(MirroringType::Vertical); break;
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case 1: SetMirroringType(MirroringType::Horizontal); break;
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case 2: SetMirroringType(MirroringType::ScreenAOnly); break;
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case 3: SetMirroringType(MirroringType::ScreenBOnly); break;
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}
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UpdatePrgRamAccess();
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}
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void WriteRegister(uint16_t addr, uint8_t value)
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{
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if(addr & 0x10 && (addr & 0xF010) != 0x9010) {
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addr |= 0x08;
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}
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switch(addr & 0xF008) {
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case 0x8000: SelectPRGPage(0, value & 0x3F); break;
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case 0x8008: SelectPRGPage(1, value & 0x3F); break;
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case 0x9000: SelectPRGPage(2, value & 0x3F); break;
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case 0x9010: break; //Audio
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case 0x9030: break; //Audio
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case 0xA000: SelectCHRPage(0, value); break;
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case 0xA008: SelectCHRPage(1, value); break;
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case 0xB000: SelectCHRPage(2, value); break;
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case 0xB008: SelectCHRPage(3, value); break;
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case 0xC000: SelectCHRPage(4, value); break;
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case 0xC008: SelectCHRPage(5, value); break;
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case 0xD000: SelectCHRPage(6, value); break;
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case 0xD008: SelectCHRPage(7, value); break;
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case 0xE000: _controlFlags = value; UpdateState(); break;
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case 0xE008: _irq.SetReloadValue(value); break;
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case 0xF000: _irq.SetControlValue(value); break;
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case 0xF008: _irq.AcknowledgeIrq(); break;
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}
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}
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}; |