z80/ym2612 reset handling improved
[picodrive.git] / Pico / PicoFrameHints.c
... / ...
CommitLineData
1// common code for Pico.c and cd/Pico.c
2// (c) Copyright 2007,2008 Grazvydas "notaz" Ignotas
3
4#define CYCLES_M68K_LINE 488 // suitable for both PAL/NTSC
5#define CYCLES_M68K_VINT_LAG 68
6#define CYCLES_M68K_ASD 148
7#define CYCLES_S68K_LINE 795
8#define CYCLES_S68K_ASD 241
9
10// pad delay (for 6 button pads)
11#define PAD_DELAY \
12 if (PicoOpt&POPT_6BTN_PAD) { \
13 if(Pico.m.padDelay[0]++ > 25) Pico.m.padTHPhase[0]=0; \
14 if(Pico.m.padDelay[1]++ > 25) Pico.m.padTHPhase[1]=0; \
15 }
16
17// CPUS_RUN
18#ifndef PICO_CD
19#define CPUS_RUN(m68k_cycles,s68k_cycles) \
20 SekRunM68k(m68k_cycles);
21#else
22#define CPUS_RUN(m68k_cycles,s68k_cycles) \
23{ \
24 if ((PicoOpt&POPT_EN_MCD_PSYNC) && (Pico_mcd->m.busreq&3) == 1) { \
25 SekRunPS(m68k_cycles, s68k_cycles); /* "better/perfect sync" */ \
26 } else { \
27 SekRunM68k(m68k_cycles); \
28 if ((Pico_mcd->m.busreq&3) == 1) /* no busreq/no reset */ \
29 SekRunS68k(s68k_cycles); \
30 } \
31}
32#endif
33
34// Accurate but slower frame which does hints
35static int PicoFrameHints(void)
36{
37 struct PicoVideo *pv=&Pico.video;
38 int lines, y, lines_vis = 224, line_sample, skip, vcnt_wrap;
39 int hint; // Hint counter
40
41 pv->v_counter = Pico.m.scanline = 0;
42
43 if ((PicoOpt&POPT_ALT_RENDERER) && !PicoSkipFrame && (pv->reg[1]&0x40)) { // fast rend., display enabled
44 // draw a frame just after vblank in alternative render mode
45 // yes, this will cause 1 frame lag, but this is inaccurate mode anyway.
46 PicoFrameFull();
47#ifdef DRAW_FINISH_FUNC
48 DRAW_FINISH_FUNC();
49#endif
50 skip = 1;
51 }
52 else skip=PicoSkipFrame;
53
54 if (Pico.m.pal) {
55 line_sample = 68;
56 if (pv->reg[1]&8) lines_vis = 240;
57 } else {
58 line_sample = 93;
59 }
60
61 SekCyclesReset();
62 z80_resetCycles();
63#ifdef PICO_CD
64 SekCyclesResetS68k();
65#endif
66 PsndDacLine = 0;
67
68 pv->status&=~0x88; // clear V-Int, come out of vblank
69
70 hint=pv->reg[10]; // Load H-Int counter
71 //dprintf("-hint: %i", hint);
72
73 // This is to make active scan longer (needed for Double Dragon 2, mainly)
74 CPUS_RUN(CYCLES_M68K_ASD, CYCLES_S68K_ASD);
75
76 for (y = 0; y < lines_vis; y++)
77 {
78 pv->v_counter = Pico.m.scanline = y;
79 if ((pv->reg[12]&6) == 6) { // interlace mode 2
80 pv->v_counter <<= 1;
81 pv->v_counter |= pv->v_counter >> 8;
82 pv->v_counter &= 0xff;
83 }
84
85 // VDP FIFO
86 pv->lwrite_cnt -= 12;
87 if (pv->lwrite_cnt <= 0) {
88 pv->lwrite_cnt=0;
89 Pico.video.status|=0x200;
90 }
91
92 PAD_DELAY
93#ifdef PICO_CD
94 check_cd_dma();
95#endif
96
97 // H-Interrupts:
98 if (--hint < 0) // y <= lines_vis: Comix Zone, Golden Axe
99 {
100 hint=pv->reg[10]; // Reload H-Int counter
101 pv->pending_ints|=0x10;
102 if (pv->reg[0]&0x10) {
103 elprintf(EL_INTS, "hint: @ %06x [%i]", SekPc, SekCycleCnt);
104 SekInterrupt(4);
105 }
106 }
107
108 // decide if we draw this line
109 if (!skip && (PicoOpt & POPT_ALT_RENDERER))
110 {
111 // find the right moment for frame renderer, when display is no longer blanked
112 if ((pv->reg[1]&0x40) || y > 100) {
113 PicoFrameFull();
114#ifdef DRAW_FINISH_FUNC
115 DRAW_FINISH_FUNC();
116#endif
117 skip = 1;
118 }
119 }
120
121#ifndef PICO_CD
122 // get samples from sound chips
123 if (y == 32 && PsndOut)
124 emustatus &= ~1;
125 else if ((y == 224 || y == line_sample) && PsndOut)
126 {
127 if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80))
128 PicoSyncZ80(SekCycleCnt);
129 if (ym2612.dacen && PsndDacLine <= y)
130 PsndDoDAC(y);
131 getSamples(y);
132 }
133#endif
134
135 // Run scanline:
136 if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
137 CPUS_RUN(CYCLES_M68K_LINE, CYCLES_S68K_LINE);
138
139#ifdef PICO_CD
140 update_chips();
141#else
142 if (PicoLineHook) PicoLineHook();
143#endif
144 }
145
146 if (!skip)
147 {
148 if (DrawScanline < y)
149 PicoDrawSync(y - 1, 0);
150#ifdef DRAW_FINISH_FUNC
151 DRAW_FINISH_FUNC();
152#endif
153 }
154
155 // V-int line (224 or 240)
156 Pico.m.scanline = y;
157 pv->v_counter = 0xe0; // bad for 240 mode
158 if ((pv->reg[12]&6) == 6) pv->v_counter = 0xc1;
159
160 // VDP FIFO
161 pv->lwrite_cnt=0;
162 Pico.video.status|=0x200;
163
164 PAD_DELAY
165#ifdef PICO_CD
166 check_cd_dma();
167#endif
168
169 // Last H-Int:
170 if (--hint < 0)
171 {
172 hint=pv->reg[10]; // Reload H-Int counter
173 pv->pending_ints|=0x10;
174 //printf("rhint: %i @ %06x [%i|%i]\n", hint, SekPc, y, SekCycleCnt);
175 if (pv->reg[0]&0x10) SekInterrupt(4);
176 }
177
178 pv->status|=0x08; // go into vblank
179 pv->pending_ints|=0x20;
180
181 // the following SekRun is there for several reasons:
182 // there must be a delay after vblank bit is set and irq is asserted (Mazin Saga)
183 // also delay between F bit (bit 7) is set in SR and IRQ happens (Ex-Mutants)
184 // also delay between last H-int and V-int (Golden Axe 3)
185 SekRunM68k(CYCLES_M68K_VINT_LAG);
186
187 if (pv->reg[1]&0x20) {
188 elprintf(EL_INTS, "vint: @ %06x [%i]", SekPc, SekCycleCnt);
189 SekInterrupt(6);
190 }
191 if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80)) {
192 PicoSyncZ80(SekCycleCnt);
193 elprintf(EL_INTS, "zint");
194 z80_int();
195 }
196
197 // get samples from sound chips
198#ifndef PICO_CD
199 if (y == 224)
200#endif
201 if (PsndOut)
202 {
203 if (ym2612.dacen && PsndDacLine <= y)
204 PsndDoDAC(y);
205 getSamples(y);
206 }
207
208 // Run scanline:
209 if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
210 CPUS_RUN(CYCLES_M68K_LINE - CYCLES_M68K_VINT_LAG - CYCLES_M68K_ASD,
211 CYCLES_S68K_LINE - CYCLES_S68K_ASD);
212
213#ifdef PICO_CD
214 update_chips();
215#else
216 if (PicoLineHook) PicoLineHook();
217#endif
218
219 // PAL line count might actually be 313 according to Steve Snake, but that would complicate things.
220 lines = Pico.m.pal ? 312 : 262;
221 vcnt_wrap = Pico.m.pal ? 0x103 : 0xEB; // based on Gens
222
223 for (y++; y < lines; y++)
224 {
225 pv->v_counter = Pico.m.scanline = y;
226 if (y >= vcnt_wrap)
227 pv->v_counter -= Pico.m.pal ? 56 : 6;
228 if ((pv->reg[12]&6) == 6)
229 pv->v_counter = (pv->v_counter << 1) | 1;
230 pv->v_counter &= 0xff;
231
232 PAD_DELAY
233#ifdef PICO_CD
234 check_cd_dma();
235#endif
236
237 // Run scanline:
238 if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
239 CPUS_RUN(CYCLES_M68K_LINE, CYCLES_S68K_LINE);
240
241#ifdef PICO_CD
242 update_chips();
243#else
244 if (PicoLineHook) PicoLineHook();
245#endif
246 }
247
248 // sync z80
249 if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoOpt&POPT_EN_Z80))
250 PicoSyncZ80(Pico.m.pal ? 151809 : 127671); // cycles adjusted for converter
251 if (PsndOut && ym2612.dacen && PsndDacLine <= lines-1)
252 PsndDoDAC(lines-1);
253
254 timers_cycle();
255
256 return 0;
257}
258
259#undef PAD_DELAY
260#undef CPUS_RUN
261