Mesen/Core/SunsoftFme7.h
2017-02-18 12:58:40 -05:00

125 lines
2.9 KiB
C++

#pragma once
#include "stdafx.h"
#include "BaseMapper.h"
#include "CPU.h"
#include "Sunsoft5bAudio.h"
class SunsoftFme7 : public BaseMapper
{
private:
Sunsoft5bAudio _audio;
uint8_t _command;
uint8_t _workRamValue;
bool _irqEnabled;
bool _irqCounterEnabled;
uint16_t _irqCounter;
protected:
virtual uint16_t GetPRGPageSize() override { return 0x2000; }
virtual uint16_t GetCHRPageSize() override { return 0x400; }
virtual uint32_t GetWorkRamSize() override { return 0x8000; }
virtual uint32_t GetWorkRamPageSize() override { return 0x2000; }
virtual uint32_t GetSaveRamSize() override { return 0x8000; }
virtual uint32_t GetSaveRamPageSize() override { return 0x2000; }
void InitMapper() override
{
_command = 0;
_workRamValue = 0;
_irqEnabled = false;
_irqCounterEnabled = false;
_irqCounter = 0;
SelectPRGPage(3, -1);
UpdateWorkRam();
}
void StreamState(bool saving) override
{
BaseMapper::StreamState(saving);
SnapshotInfo audio{ &_audio };
Stream(_command, _workRamValue, _irqEnabled, _irqCounterEnabled, _irqCounter, audio);
if(!saving) {
UpdateWorkRam();
}
}
void ProcessCpuClock() override
{
if(_irqCounterEnabled) {
_irqCounter--;
if(_irqCounter == 0xFFFF) {
if(_irqEnabled) {
CPU::SetIRQSource(IRQSource::External);
}
}
}
_audio.Clock();
}
void UpdateWorkRam()
{
if(_workRamValue & 0x40) {
MemoryAccessType accessType = (_workRamValue & 0x80) ? MemoryAccessType::ReadWrite : MemoryAccessType::NoAccess;
SetCpuMemoryMapping(0x6000, 0x7FFF, _workRamValue & 0x3F, HasBattery() ? PrgMemoryType::SaveRam : PrgMemoryType::WorkRam, accessType);
} else {
SetCpuMemoryMapping(0x6000, 0x7FFF, _workRamValue & 0x3F, PrgMemoryType::PrgRom);
}
}
void WriteRegister(uint16_t addr, uint8_t value) override
{
switch(addr & 0xE000) {
case 0x8000:
_command = value;
break;
case 0xA000:
switch(_command) {
case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
SelectCHRPage(_command, value);
break;
case 8: {
_workRamValue = value;
UpdateWorkRam();
break;
}
case 9: case 0xA: case 0xB:
SelectPRGPage(_command - 9, value & 0x3F);
break;
case 0xC:
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;
}
break;
case 0xD:
_irqEnabled = (value & 0x01) == 0x01;
_irqCounterEnabled = (value & 0x80) == 0x80;
CPU::ClearIRQSource(IRQSource::External);
break;
case 0xE:
_irqCounter = _irqCounter & 0xFF00 | value;
break;
case 0xF:
_irqCounter = _irqCounter & 0xFF | (value << 8);
break;
}
break;
case 0xC000:
case 0xE000:
_audio.WriteRegister(addr, value);
break;
}
}
};