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1 | /* FCE Ultra - NES/Famicom Emulator |
2 | * |
3 | * Copyright notice for this file: |
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4 | * Copyright (C) 2002 Xodnizel |
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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 |
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18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
19 | * (VRC4 mapper) |
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20 | */ |
21 | |
22 | #include "mapinc.h" |
23 | |
24 | #define K4buf mapbyte2 |
25 | #define K4IRQ mapbyte1[1] |
26 | #define K4sel mapbyte1[0] |
27 | |
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28 | static int acount=0; |
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29 | static int weirdo=0; |
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30 | static DECLFW(Mapper25_write) |
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31 | { |
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32 | if(A==0xC007) |
33 | { |
34 | weirdo=8; // Ganbare Goemon Gaiden does strange things!!! at the end credits |
35 | // quick dirty hack, seems there is no other games with such PCB, so |
36 | // we never know if it will not work for something else lol |
37 | VROM_BANK1(0x0000,0xFC); |
38 | VROM_BANK1(0x0400,0xFD); |
39 | VROM_BANK1(0x0800,0xFF); |
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40 | } |
41 | |
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42 | A=(A&0xF003)|((A&0xC)>>2); |
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43 | |
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44 | if((A&0xF000)==0xA000) |
45 | ROM_BANK8(0xA000,V); |
46 | else if(A>=0xB000 && A<=0xEFFF) |
47 | { |
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48 | int x=(A&1)|((A-0xB000)>>11); |
49 | |
50 | K4buf[x]&=(0xF0)>>((A&2)<<1); |
51 | K4buf[x]|=(V&0xF)<<((A&2)<<1); |
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52 | if(weirdo) |
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53 | weirdo--; |
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54 | else |
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55 | VROM_BANK1(x<<10,K4buf[x]); |
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56 | } |
57 | else if((A&0xF000)==0x8000) |
58 | { |
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59 | if(K4sel&2) |
60 | ROM_BANK8(0xC000,V); |
61 | else |
62 | ROM_BANK8(0x8000,V); |
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63 | } |
64 | else switch(A) |
65 | { |
66 | case 0x9000:switch(V&0x3) |
67 | { |
68 | case 0:MIRROR_SET(0);break; |
69 | case 1:MIRROR_SET(1);break; |
70 | case 2:onemir(0);break; |
71 | case 3:onemir(1);break; |
72 | } |
73 | break; |
74 | case 0x9001:if((K4sel&2)!=(V&2)) |
75 | { |
76 | uint8 swa; |
77 | swa=PRGBankList[0]; |
78 | ROM_BANK8(0x8000,PRGBankList[2]); |
79 | ROM_BANK8(0xc000,swa); |
80 | } |
81 | K4sel=V; |
82 | break; |
83 | case 0xf000:IRQLatch&=0xF0;IRQLatch|=V&0xF;break; |
84 | case 0xf002:IRQLatch&=0x0F;IRQLatch|=V<<4;break; |
85 | case 0xf001:IRQCount=IRQLatch;IRQa=V&2;K4IRQ=V&1;acount=0;X6502_IRQEnd(FCEU_IQEXT);break; |
86 | case 0xf003:IRQa=K4IRQ;X6502_IRQEnd(FCEU_IQEXT);break; |
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87 | } |
88 | } |
89 | |
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90 | static void FP_FASTAPASS(1) KonamiIRQHook(int a) |
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91 | { |
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92 | // #define LCYCS ((227*2)) |
93 | #define LCYCS 341 |
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94 | if(IRQa) |
95 | { |
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96 | acount+=a*3; |
97 | // acount+=a*4; |
98 | if(acount>=LCYCS) |
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99 | { |
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100 | doagainbub:acount-=LCYCS;IRQCount++; |
101 | if(IRQCount&0x100) |
102 | {//acount=0; |
103 | X6502_IRQBegin(FCEU_IQEXT);IRQCount=IRQLatch; |
104 | } |
105 | if(acount>=LCYCS) goto doagainbub; |
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106 | } |
107 | } |
108 | } |
109 | |
110 | void Mapper25_init(void) |
111 | { |
112 | SetWriteHandler(0x8000,0xffff,Mapper25_write); |
113 | MapIRQHook=KonamiIRQHook; |
114 | } |
115 | |