139 lines
No EOL
3.6 KiB
C++
139 lines
No EOL
3.6 KiB
C++
#pragma once
|
|
#include "stdafx.h"
|
|
#include "BaseMapper.h"
|
|
#include "CPU.h"
|
|
|
|
class Sunsoft4 : public BaseMapper
|
|
{
|
|
private:
|
|
uint8_t _ntRegs[2];
|
|
bool _useChrForNametables;
|
|
bool _prgRamEnabled;
|
|
uint32_t _licensingTimer;
|
|
bool _usingExternalRom;
|
|
uint8_t _externalPage = 0;
|
|
|
|
void UpdateNametables()
|
|
{
|
|
if(_useChrForNametables) {
|
|
for(int i = 0; i < 4; i++) {
|
|
uint8_t reg = 0;
|
|
switch(GetMirroringType()) {
|
|
case MirroringType::FourScreens: break; //4-screen mirroring is not supported by this mapper
|
|
case MirroringType::Vertical: reg = i & 0x01; break;
|
|
case MirroringType::Horizontal: reg = (i & 0x02) >> 1; break;
|
|
case MirroringType::ScreenAOnly: reg = 0; break;
|
|
case MirroringType::ScreenBOnly: reg = 1; break;
|
|
}
|
|
|
|
SetPpuMemoryMapping(0x2000+i*0x400, 0x2000+i*0x400+0x3FF, ChrMemoryType::Default, _ntRegs[reg] * 0x400, _chrRamSize > 0 ? MemoryAccessType::ReadWrite : MemoryAccessType::Read);
|
|
}
|
|
} else {
|
|
//Reset to default mirroring
|
|
SetMirroringType(GetMirroringType());
|
|
}
|
|
}
|
|
|
|
protected:
|
|
virtual uint16_t GetPRGPageSize() override { return 0x4000; }
|
|
virtual uint16_t GetCHRPageSize() override { return 0x800; }
|
|
|
|
void InitMapper() override
|
|
{
|
|
_useChrForNametables = false;
|
|
_ntRegs[0] = _ntRegs[1] = 0;
|
|
|
|
_licensingTimer = 0;
|
|
_usingExternalRom = false;
|
|
_prgRamEnabled = false;
|
|
|
|
//Bank 0's initial state is undefined, but some roms expect it to be the first page
|
|
SelectPRGPage(0, 0);
|
|
SelectPRGPage(1, 7);
|
|
|
|
UpdateState();
|
|
}
|
|
|
|
void StreamState(bool saving) override
|
|
{
|
|
BaseMapper::StreamState(saving);
|
|
|
|
Stream(_ntRegs[0], _ntRegs[1], _useChrForNametables, _prgRamEnabled, _usingExternalRom, _externalPage);
|
|
}
|
|
|
|
void UpdateState()
|
|
{
|
|
MemoryAccessType access = _prgRamEnabled ? MemoryAccessType::ReadWrite : MemoryAccessType::NoAccess;
|
|
SetCpuMemoryMapping(0x6000, 0x7FFF, 0, HasBattery() ? PrgMemoryType::SaveRam : PrgMemoryType::WorkRam);
|
|
|
|
if(_usingExternalRom) {
|
|
if(_licensingTimer == 0) {
|
|
RemoveCpuMemoryMapping(0x8000, 0xBFFF);
|
|
} else {
|
|
SelectPRGPage(0, _externalPage);
|
|
}
|
|
}
|
|
}
|
|
|
|
void ProcessCpuClock() override
|
|
{
|
|
if(_licensingTimer) {
|
|
_licensingTimer--;
|
|
if(_licensingTimer == 0) {
|
|
UpdateState();
|
|
}
|
|
}
|
|
}
|
|
|
|
void WriteRAM(uint16_t addr, uint8_t value) override
|
|
{
|
|
if(addr >= 0x6000 && addr <= 0x7FFF) {
|
|
_licensingTimer = 1024 * 105;
|
|
UpdateState();
|
|
}
|
|
BaseMapper::WriteRAM(addr, value);
|
|
}
|
|
|
|
void WriteRegister(uint16_t addr, uint8_t value) override
|
|
{
|
|
switch(addr & 0xF000) {
|
|
case 0x8000: SelectCHRPage(0, value); break;
|
|
case 0x9000: SelectCHRPage(1, value); break;
|
|
case 0xA000: SelectCHRPage(2, value); break;
|
|
case 0xB000: SelectCHRPage(3, value); break;
|
|
case 0xC000:
|
|
_ntRegs[0] = value | 0x80;
|
|
UpdateNametables();
|
|
break;
|
|
case 0xD000:
|
|
_ntRegs[1] = value | 0x80;
|
|
UpdateNametables();
|
|
break;
|
|
case 0xE000:
|
|
switch(value & 0x03) {
|
|
case 0: SetMirroringType(MirroringType::Vertical); break;
|
|
case 1: SetMirroringType(MirroringType::Horizontal); break;
|
|
case 2: SetMirroringType(MirroringType::ScreenAOnly); break;
|
|
case 3: SetMirroringType(MirroringType::ScreenBOnly); break;
|
|
}
|
|
_useChrForNametables = (value & 0x10) == 0x10;
|
|
UpdateNametables();
|
|
break;
|
|
case 0xF000:
|
|
bool externalPrg = (value & 0x08) == 0;
|
|
if(externalPrg && GetPRGPageCount() > 8) {
|
|
_usingExternalRom = true;
|
|
_externalPage = 0x08 | ((value & 0x07) % (GetPRGPageCount() - 0x08));
|
|
SelectPRGPage(0, _externalPage);
|
|
} else {
|
|
_usingExternalRom = false;
|
|
SelectPRGPage(0, value & 0x07);
|
|
}
|
|
|
|
_prgRamEnabled = (value & 0x10) == 0x10;
|
|
UpdateState();
|
|
|
|
break;
|
|
}
|
|
}
|
|
}; |