mmuhack, 6502 tweaks, fskip
[fceu.git] / mappers / 40.c
CommitLineData
c62d2810 1/* FCE Ultra - NES/Famicom Emulator
2 *
3 * Copyright notice for this file:
4 * Copyright (C) 2002 Ben Parnell
5 *
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.
10 *
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.
15 *
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
19 */
20
21#include "mapinc.h"
22
23
24static DECLFW(Mapper40_write)
25{
26 switch(A&0xe000)
27 {
28 case 0x8000:IRQa=0;IRQCount=0;break;
29 case 0xa000:IRQa=1;break;
30 case 0xe000:ROM_BANK8(0xc000,V&7);break;
31 }
32}
33
34static void FP_FASTAPASS(1) Mapper40IRQ(int a)
35{
36 if(IRQa)
37 {
38 if(IRQCount<4096)
39 IRQCount+=a;
40 else
41 {
42 IRQa=0;
43 TriggerIRQ();
44 }
45 }
46}
47
48void Mapper40_init(void)
49{
50 ROM_BANK8(0x6000,(~0)-1);
51 ROM_BANK8(0x8000,(~0)-3);
52 ROM_BANK8(0xa000,(~0)-2);
53 SetWriteHandler(0x8000,0xffff,Mapper40_write);
54 SetReadHandler(0x6000,0x7fff,CartBR);
55 MapIRQHook=Mapper40IRQ;
56}
57
58