Mesen/Core/TaitoX1005.h
2024-01-29 12:44:24 -05:00

116 lines
2.9 KiB
C++

#pragma once
#include "stdafx.h"
#include "BaseMapper.h"
class TaitoX1005 : public BaseMapper
{
private:
bool _alternateMirroring;
uint8_t _ramPermission;
void UpdateRamAccess()
{
SetCpuMemoryMapping(0x7F00, 0x7FFF, 0, HasBattery() ? PrgMemoryType::SaveRam : PrgMemoryType::WorkRam, _ramPermission == 0xA3 ? MemoryAccessType::ReadWrite : MemoryAccessType::NoAccess);
}
protected:
virtual uint16_t GetPRGPageSize() override { return 0x2000; }
virtual uint16_t GetCHRPageSize() override { return 0x0400; }
virtual uint16_t RegisterStartAddress() override { return 0x7EF0; }
virtual uint16_t RegisterEndAddress() override { return 0x7EFF; }
virtual uint32_t GetWorkRamSize() override { return 0x100; }
virtual uint32_t GetWorkRamPageSize() override { return 0x100; }
virtual uint32_t GetSaveRamSize() override { return 0x100; }
virtual uint32_t GetSaveRamPageSize() override { return 0x100; }
bool ForceSaveRamSize() override { return HasBattery(); }
bool ForceWorkRamSize() override { return !HasBattery(); }
void InitMapper() override
{
_ramPermission = 0;
SelectPRGPage(3, -1);
UpdateRamAccess();
}
void WriteRAM(uint16_t addr, uint8_t value) override
{
if((addr & 0xFF00) == 0x7F00) {
//Mirror writes to the top/bottom - the mapper only has 128 bytes of ram, mirrored once.
//The current BaseMapper code doesn't support mapping blocks smaller than 256 bytes,
//so doing this at least ensures it behaves like a mirrored 128-byte block of ram
BaseMapper::WriteRAM(addr ^ 0x80, value);
}
BaseMapper::WriteRAM(addr, value);
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
switch(addr) {
case 0x7EF0:
SelectCHRPage(0, value);
SelectCHRPage(1, value + 1);
if(_alternateMirroring) {
SetNametable(0, value >> 7);
SetNametable(1, value >> 7);
}
break;
case 0x7EF1:
SelectCHRPage(2, value );
SelectCHRPage(3, value + 1);
if(_alternateMirroring) {
SetNametable(2, value >> 7);
SetNametable(3, value >> 7);
}
break;
case 0x7EF2: SelectCHRPage(4, value); break;
case 0x7EF3: SelectCHRPage(5, value); break;
case 0x7EF4: SelectCHRPage(6, value); break;
case 0x7EF5: SelectCHRPage(7, value); break;
case 0x7EF6: case 0x7EF7:
if(!_alternateMirroring) {
SetMirroringType((value & 0x01) == 0x01 ? MirroringType::Vertical : MirroringType::Horizontal);
}
break;
case 0x7EF8: case 0x7EF9:
_ramPermission = value;
UpdateRamAccess();
break;
case 0x7EFA: case 0x7EFB:
SelectPRGPage(0, value);
break;
case 0x7EFC: case 0x7EFD:
SelectPRGPage(1, value);
break;
case 0x7EFE: case 0x7EFF:
SelectPRGPage(2, value);
break;
}
}
virtual void StreamState(bool saving) override
{
BaseMapper::StreamState(saving);
Stream(_ramPermission);
if(!saving) {
UpdateRamAccess();
}
}
public:
TaitoX1005(bool alternateMirroring) : _alternateMirroring(alternateMirroring)
{
}
};