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fceugx/source/fceultra/boards/413.cpp
2025-03-23 14:17:12 -06:00

148 lines
3.1 KiB
C++

/* FCEUmm - NES/Famicom Emulator
*
* Copyright notice for this file:
* Copyright (C) 2024
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "mapinc.h"
#include "../ines.h"
static uint8 reg[4];
static uint8 IRQCount;
static uint8 IRQReload;
static uint8 IRQa;
static uint8 serialControl;
static uint32 serialAddress;
static SFORMAT StateRegs[] = {
{ reg, 4, "REGS" },
{ &IRQCount, 1, "IRQC" },
{ &IRQReload, 1, "IRQR" },
{ &IRQa, 1, "IRQA" },
{ &serialAddress, 4, "ADDR" },
{ &serialControl, 1, "CTRL" },
{ 0 }
};
static void Sync(void) {
setprg4(0x5000, 0x01);
setprg8(0x6000, reg[0]);
setprg8(0x8000, reg[1]);
setprg8(0xA000, reg[2]);
setprg4(0xD000, 0x07);
setprg8(0xE000, 0x04);
setchr4(0x0000, reg[3]);
setchr4(0x1000, ~0x02);
}
static uint64 lreset;
static uint32 laddr;
static DECLFR(M413ReadPCM) {
uint8 ret = X.DB;
if ((A == laddr) && ((timestampbase + timestamp) < (lreset + 4))) {
return ret;
}
if (serialControl & 0x02) {
ret = MiscROM[serialAddress++ & (MiscROM_size - 1)];
} else {
ret = MiscROM[serialAddress & (MiscROM_size - 1)];
}
laddr = A;
lreset = timestampbase + timestamp;
return ret;
}
static DECLFW(M413Write) {
switch (A & 0xF000) {
case 0x8000:
IRQReload = V;
break;
case 0x9000:
IRQCount = 0;
break;
case 0xA000:
case 0xB000:
IRQa = (A & 0x1000) != 0;
if (!IRQa) {
X6502_IRQEnd(FCEU_IQEXT);
}
break;
case 0xC000:
serialAddress = (serialAddress << 1) | (V >> 7);
break;
case 0xD000:
serialControl = V;
break;
case 0xE000:
case 0xF000:
reg[V >> 6] = V & 0x3F;
Sync();
break;
}
}
static void M413Power(void) {
serialAddress = 0;
serialControl = 0;
IRQCount = 0;
IRQReload = 0;
IRQa = 0;
reg[0] = 0;
reg[1] = 0;
reg[2] = 0;
reg[3] = 0;
laddr = 0;
lreset = 0;
Sync();
SetReadHandler(0x4800, 0x4FFF, M413ReadPCM);
SetReadHandler(0x5000, 0x7FFF, CartBR);
SetReadHandler(0x8000, 0xBFFF, CartBR);
SetReadHandler(0xC000, 0xCFFF, M413ReadPCM);
SetReadHandler(0xD000, 0xFFFF, CartBR);
SetWriteHandler(0x8000, 0xFFFF, M413Write);
}
static void M413IRQHook(void) {
if (IRQCount == 0) {
IRQCount = IRQReload;
} else {
IRQCount--;
}
if ((IRQCount == 0) && IRQa) {
X6502_IRQBegin(FCEU_IQEXT);
}
}
static void StateRestore(int version) {
Sync();
}
void Mapper413_Init(CartInfo *info) {
info->Power = M413Power;
GameHBIRQHook = M413IRQHook;
GameStateRestore = StateRestore;
AddExState(&StateRegs, ~0, 0, 0);
}