+/* FCE Ultra - NES/Famicom Emulator
+ *
+ * Copyright notice for this file:
+ * Copyright (C) 2005 CaH4e3
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include "mapinc.h"
+
+static uint16 IRQCount;
+static uint8 IRQa;
+static uint8 prg_reg[2];
+static uint8 chr_reg[8];
+
+static SFORMAT StateRegs[]=
+{
+ {&IRQCount, 2, "IRQC"},
+ {&IRQa, 2, "IRQA"},
+ {prg_reg, 2, "PRG"},
+ {chr_reg, 8, "CHR"},
+ {0}
+};
+
+static void M222IRQ(void)
+{
+ if(IRQa)
+ {
+ IRQCount++;
+ if(IRQCount>=240)
+ {
+ X6502_IRQBegin(FCEU_IQEXT);
+ IRQa=0;
+ }
+ }
+}
+
+static void Sync(void)
+{
+ setprg8(0x8000,prg_reg[0]);
+ setprg8(0xA000,prg_reg[1]);
+ int i;
+ for(i=0; i<8; i++)
+ setchr1(i<<10,chr_reg[i]);
+}
+
+static DECLFW(M222Write)
+{
+ switch(A&0xF003)
+ {
+ case 0x8000: prg_reg[0]=V; break;
+ case 0xA000: prg_reg[1]=V; break;
+ case 0xB000: chr_reg[0]=V; break;
+ case 0xB002: chr_reg[1]=V; break;
+ case 0xC000: chr_reg[2]=V; break;
+ case 0xC002: chr_reg[3]=V; break;
+ case 0xD000: chr_reg[4]=V; break;
+ case 0xD002: chr_reg[5]=V; break;
+ case 0xE000: chr_reg[6]=V; break;
+ case 0xE002: chr_reg[7]=V; break;
+ case 0xF000: IRQCount=IRQa=V;
+ X6502_IRQEnd(FCEU_IQEXT);
+ break;
+ }
+ Sync();
+}
+
+static void M222Power(void)
+{
+ setprg16(0xC000,~0);
+ SetReadHandler(0x8000,0xFFFF,CartBR);
+ SetWriteHandler(0x8000,0xFFFF,M222Write);
+}
+
+static void StateRestore(int version)
+{
+ Sync();
+}
+
+void Mapper222_Init(CartInfo *info)
+{
+ info->Power=M222Power;
+ GameHBIRQHook=M222IRQ;
+ GameStateRestore=StateRestore;
+ AddExState(&StateRegs, ~0, 0, 0);
+}