1 /* FCE Ultra - NES/Famicom Emulator
3 * Copyright notice for this file:
4 * Copyright (C) 2002 Xodnizel
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #define K4buf mapbyte2
24 #define K4IRQ mapbyte1[1]
25 #define K4sel mapbyte1[0]
29 DECLFW(Mapper21_write)
33 if((A&0xF000)==0xA000)
35 else if((A&0xF000)==0x8000)
42 else if(A>=0xb000 && A<=0xefff)
46 int x=((A>>2)&1)|((A-0xB000)>>11);
48 K4buf[x]&=(0xF0)>>((A&2)<<1);
49 K4buf[x]|=(V&0xF)<<((A&2)<<1);
50 VROM_BANK1(x<<10,K4buf[x]);
59 case 0:MIRROR_SET(0);break;
60 case 1:MIRROR_SET(1);break;
61 case 2:onemir(0);break;
62 case 3:onemir(1);break;
67 case 0x9002:if((K4sel&2)!=(V&2))
71 ROM_BANK8(0x8000,PRGBankList[2]);
72 ROM_BANK8(0xc000,swa);
76 case 0xf000:IRQLatch&=0xF0;IRQLatch|=V&0xF;break;
77 case 0xf002:IRQLatch&=0x0F;IRQLatch|=V<<4;break;
78 case 0xf004:IRQCount=IRQLatch;acount=0;
80 X6502_IRQEnd(FCEU_IQEXT);
82 case 0xf006:IRQa=K4IRQ;X6502_IRQEnd(FCEU_IQEXT);break;
85 static void FP_FASTAPASS(1) KonamiIRQHook(int a)
87 #define LCYCS ((227*2)+1)
95 doagainbub:acount-=LCYCS;IRQCount++;
96 if(IRQCount&0x100) {X6502_IRQBegin(FCEU_IQEXT);IRQCount=IRQLatch;}
97 if(acount>=LCYCS) goto doagainbub;
102 void Mapper21_init(void)
104 SetWriteHandler(0x8000,0xffff,Mapper21_write);
105 MapIRQHook=KonamiIRQHook;