mirror of
https://github.com/libretro/Mesen.git
synced 2024-12-13 11:57:09 +00:00
94 lines
2.2 KiB
C++
94 lines
2.2 KiB
C++
#pragma once
|
|
#include "stdafx.h"
|
|
#include "TaitoTc0190.h"
|
|
#include "MMC3.h"
|
|
|
|
class TaitoTc0690 : public MMC3
|
|
{
|
|
private:
|
|
uint8_t _irqDelay;
|
|
bool _isFlintstones;
|
|
|
|
protected:
|
|
virtual void InitMapper() override
|
|
{
|
|
_irqDelay = 0;
|
|
SelectPRGPage(2, -2);
|
|
SelectPRGPage(3, -1);
|
|
|
|
//This cart appears to behave differently (maybe not an identical mapper?)
|
|
//IRQ seems to be triggered at a different timing (approx 100 cpu cycles before regular mapper 48 timings)
|
|
_isFlintstones = _subMapperID == 255;
|
|
}
|
|
|
|
virtual void StreamState(bool saving) override
|
|
{
|
|
MMC3::StreamState(saving);
|
|
Stream(_irqDelay);
|
|
}
|
|
|
|
virtual void TriggerIrq() override
|
|
{
|
|
//"The IRQ seems to trip a little later than it does on MMC3. It looks like about a 4 CPU cycle delay from the normal MMC3 IRQ time."
|
|
//A value of 6 removes the shaking from The Jetsons
|
|
_irqDelay = _isFlintstones ? 19 : 6;
|
|
}
|
|
|
|
void ProcessCpuClock() override
|
|
{
|
|
if(_irqDelay > 0) {
|
|
_irqDelay--;
|
|
if(_irqDelay == 0) {
|
|
CPU::SetIRQSource(IRQSource::External);
|
|
}
|
|
}
|
|
}
|
|
|
|
virtual void WriteRegister(uint16_t addr, uint8_t value) override
|
|
{
|
|
switch(addr & 0xE003) {
|
|
case 0x8000:
|
|
SelectPRGPage(0, value & 0x3F);
|
|
break;
|
|
case 0x8001:
|
|
SelectPRGPage(1, value & 0x3F);
|
|
break;
|
|
case 0x8002:
|
|
SelectCHRPage(0, value * 2);
|
|
SelectCHRPage(1, value * 2 + 1);
|
|
break;
|
|
case 0x8003:
|
|
SelectCHRPage(2, value * 2);
|
|
SelectCHRPage(3, value * 2 + 1);
|
|
break;
|
|
case 0xA000: case 0xA001: case 0xA002: case 0xA003:
|
|
SelectCHRPage(4 + (addr & 0x03), value);
|
|
break;
|
|
|
|
case 0xC000:
|
|
//Flintstones expects either $C000 or $C001 to clear the irq flag
|
|
CPU::ClearIRQSource(IRQSource::External);
|
|
|
|
_irqReloadValue = (value ^ 0xFF) + (_isFlintstones ? 0 : 1);
|
|
break;
|
|
case 0xC001:
|
|
//Flintstones expects either $C000 or $C001 to clear the irq flag
|
|
CPU::ClearIRQSource(IRQSource::External);
|
|
|
|
_irqCounter = 0;
|
|
_irqReload = true;
|
|
break;
|
|
case 0xC002:
|
|
_irqEnabled = true;
|
|
break;
|
|
case 0xC003:
|
|
_irqEnabled = false;
|
|
CPU::ClearIRQSource(IRQSource::External);
|
|
break;
|
|
|
|
case 0xE000:
|
|
SetMirroringType((value & 0x40) == 0x40 ? MirroringType::Horizontal : MirroringType::Vertical);
|
|
break;
|
|
}
|
|
}
|
|
}; |