15eb0001 |
1 | \r |
2 | #include "PicoInt.h"\r |
3 | \r |
4 | int PicoVer=0x0030;\r |
5 | struct Pico Pico;\r |
6 | int PicoOpt=0;\r |
7 | \r |
8 | int PicoPad[2]; // Joypads, format is SACB RLDU\r |
9 | \r |
10 | int PicoInit()\r |
11 | {\r |
12 | // Blank space for state:\r |
13 | memset(&Pico,0,sizeof(Pico));\r |
14 | memset(&PicoPad,0,sizeof(PicoPad));\r |
15 | Pico.m.dirtyPal=1;\r |
16 | \r |
17 | // Init CPU:\r |
18 | SekInit();\r |
19 | \r |
20 | // Setup memory callbacks:\r |
21 | PicoMemInit();\r |
22 | PsndReset();\r |
23 | \r |
24 | #ifdef MSOUND\r |
25 | YM2612Init(1,7670443,PsndRate,NULL,NULL);\r |
26 | #endif\r |
27 | return 0;\r |
28 | }\r |
29 | \r |
30 | void PicoExit()\r |
31 | {\r |
32 | #ifdef MSOUND\r |
33 | YM2612Shutdown();\r |
34 | #endif\r |
35 | \r |
36 | memset(&Pico,0,sizeof(Pico));\r |
37 | }\r |
38 | \r |
39 | int PicoReset()\r |
40 | {\r |
41 | unsigned int region=0;\r |
42 | int support=0,hw=0,i=0;\r |
43 | unsigned char pal=0;\r |
44 | \r |
45 | if (Pico.romsize<=0) return 1;\r |
46 | \r |
47 | SekReset();\r |
48 | PsndReset();\r |
49 | #ifdef MSOUND\r |
50 | YM2612ResetChip(0);\r |
51 | #endif\r |
52 | \r |
53 | // Read cartridge region data:\r |
54 | region=PicoRead32(0x1f0);\r |
55 | \r |
56 | for (i=0;i<4;i++)\r |
57 | {\r |
58 | int c=0;\r |
59 | \r |
60 | c=region>>(i<<3); c&=0xff;\r |
61 | if (c<=' ') continue;\r |
62 | \r |
63 | if (c=='J') support|=1;\r |
64 | else if (c=='U') support|=4;\r |
65 | else if (c=='E') support|=8;\r |
66 | else\r |
67 | {\r |
68 | // New style code:\r |
69 | char s[2]={0,0};\r |
70 | s[0]=(char)c;\r |
71 | support|=strtol(s,NULL,16);\r |
72 | }\r |
73 | \r |
74 | }\r |
75 | \r |
76 | // Try to pick the best hardware value for English/60hz:\r |
77 | if (support&4) hw=0x80; // USA\r |
78 | else if (support&8) { hw=0xc0; pal=1; } // Europe\r |
79 | else if (support&1) hw=0x00; // Japan NTSC\r |
80 | else if (support&2) { hw=0x40; pal=1; } // Japan PAL\r |
81 | else hw=0x80; // USA\r |
82 | \r |
83 | Pico.m.hardware=(unsigned char)(hw|0x20); // No disk attached\r |
84 | Pico.m.pal=pal;\r |
85 | \r |
86 | return 0;\r |
87 | }\r |
88 | \r |
89 | static int CheckIdle()\r |
90 | {\r |
91 | unsigned char state[0x88];\r |
92 | \r |
93 | memset(state,0,sizeof(state));\r |
94 | \r |
95 | // See if the state is the same after 2 steps:\r |
96 | SekState(state); SekRun(0); SekRun(0); SekState(state+0x44);\r |
97 | if (memcmp(state,state+0x44,0x44)==0) return 1;\r |
98 | \r |
99 | return 0;\r |
100 | }\r |
101 | \r |
102 | // Accurate but slower frame which does hints\r |
103 | static int PicoFrameHints()\r |
104 | {\r |
105 | struct PicoVideo *pv=&Pico.video;\r |
106 | int total=0,aim=0;\r |
107 | int y=0;\r |
108 | int hint=0x400; // Hint counter\r |
109 | \r |
110 | pv->status|=0x08; // Go into vblank\r |
111 | \r |
112 | for (y=-38;y<224;y++)\r |
113 | {\r |
114 | if (y==0)\r |
115 | {\r |
116 | hint=pv->reg[10]; // Load H-Int counter\r |
117 | if (pv->reg[1]&0x40) pv->status&=~8; // Come out of vblank if display enabled\r |
118 | }\r |
119 | \r |
120 | // H-Interrupts:\r |
121 | if (hint<0)\r |
122 | {\r |
123 | hint=pv->reg[10]; // Reload H-Int counter\r |
124 | if (pv->reg[0]&0x10) SekInterrupt(4);\r |
125 | }\r |
126 | \r |
127 | // V-Interrupt:\r |
128 | if (y==-37)\r |
129 | {\r |
130 | pv->status|=0x80; // V-Int happened\r |
131 | if (pv->reg[1]&0x20) SekInterrupt(6);\r |
132 | }\r |
133 | \r |
134 | Pico.m.scanline=(short)y;\r |
135 | \r |
136 | // Run scanline:\r |
137 | aim+=489; total+=SekRun(aim-total);\r |
138 | \r |
139 | hint--;\r |
140 | \r |
141 | if (PicoScan && y>=0) PicoLine(y);\r |
142 | }\r |
143 | \r |
144 | SekInterrupt(0); // Cancel interrupt\r |
145 | \r |
146 | return 0;\r |
147 | }\r |
148 | \r |
149 | // Simple frame without H-Ints\r |
150 | static int PicoFrameSimple()\r |
151 | {\r |
152 | int total=0,y=0,aim=0;\r |
153 | \r |
154 | Pico.m.scanline=-64;\r |
155 | \r |
156 | // V-Blanking period:\r |
157 | if (Pico.video.reg[1]&0x20) SekInterrupt(6); // Set IRQ\r |
158 | Pico.video.status|=0x88; // V-Int happened / go into vblank\r |
159 | total+=SekRun(18560);\r |
160 | \r |
161 | // Active Scan:\r |
162 | if (Pico.video.reg[1]&0x40) Pico.video.status&=~8; // Come out of vblank if display is enabled\r |
163 | SekInterrupt(0); // Clear IRQ\r |
164 | \r |
165 | // Run in sections:\r |
166 | for (aim=18560+6839; aim<=18560+6839*16; aim+=6839)\r |
167 | {\r |
168 | int add=0;\r |
169 | if (CheckIdle()) break;\r |
170 | add=SekRun(aim-total);\r |
171 | total+=add;\r |
172 | }\r |
173 | \r |
174 | if (PicoMask&0x100)\r |
175 | if (PicoScan)\r |
176 | {\r |
177 | // Draw the screen\r |
178 | for (y=0;y<224;y++) PicoLine(y);\r |
179 | }\r |
180 | \r |
181 | return 0;\r |
182 | }\r |
183 | \r |
184 | int PicoFrame()\r |
185 | {\r |
186 | int hints=0;\r |
187 | \r |
188 | if (Pico.rom==NULL) return 1; // No Rom plugged in\r |
189 | \r |
190 | \r |
191 | PmovUpdate();\r |
192 | \r |
193 | hints=Pico.video.reg[0]&0x10;\r |
194 | \r |
195 | if (hints) PicoFrameHints();\r |
196 | else PicoFrameSimple();\r |
197 | \r |
198 | PsndRender();\r |
199 | \r |
200 | return 0;\r |
201 | }\r |
202 | \r |
203 | static int DefaultCram(int cram)\r |
204 | {\r |
205 | int high=0x0841;\r |
206 | // Convert 0000bbbb ggggrrrr\r |
207 | // to rrrr1ggg g10bbbb1\r |
208 | high|=(cram&0x00f)<<12; // Red\r |
209 | high|=(cram&0x0f0)<< 3; // Green\r |
210 | high|=(cram&0xf00)>> 7; // Blue\r |
211 | return high;\r |
212 | }\r |
213 | \r |
214 | // Function to convert Megadrive Cram into a native colour:\r |
215 | int (*PicoCram)(int cram)=DefaultCram;\r |