| 1 | // PicoDrive\r |
| 2 | \r |
| 3 | // (c) Copyright 2004 Dave, All rights reserved.\r |
| 4 | // (c) Copyright 2006-2008, Grazvydas "notaz" Ignotas\r |
| 5 | // Free for non-commercial use.\r |
| 6 | \r |
| 7 | // For commercial use, separate licencing terms must be obtained.\r |
| 8 | \r |
| 9 | \r |
| 10 | #include "pico_int.h"\r |
| 11 | #include "cd/gfx_cd.h"\r |
| 12 | \r |
| 13 | extern const unsigned char hcounts_32[];\r |
| 14 | extern const unsigned char hcounts_40[];\r |
| 15 | \r |
| 16 | #ifndef UTYPES_DEFINED\r |
| 17 | typedef unsigned char u8;\r |
| 18 | typedef unsigned short u16;\r |
| 19 | typedef unsigned int u32;\r |
| 20 | #define UTYPES_DEFINED\r |
| 21 | #endif\r |
| 22 | \r |
| 23 | int (*PicoDmaHook)(unsigned int source, int len, unsigned short **srcp, unsigned short **limitp) = NULL;\r |
| 24 | \r |
| 25 | static __inline void AutoIncrement(void)\r |
| 26 | {\r |
| 27 | Pico.video.addr=(unsigned short)(Pico.video.addr+Pico.video.reg[0xf]);\r |
| 28 | }\r |
| 29 | \r |
| 30 | static void VideoWrite(u16 d)\r |
| 31 | {\r |
| 32 | unsigned int a=Pico.video.addr;\r |
| 33 | \r |
| 34 | switch (Pico.video.type)\r |
| 35 | {\r |
| 36 | case 1: if(a&1) d=(u16)((d<<8)|(d>>8)); // If address is odd, bytes are swapped (which game needs this?)\r |
| 37 | Pico.vram [(a>>1)&0x7fff]=d;\r |
| 38 | if (a - ((unsigned)(Pico.video.reg[5]&0x7f) << 9) < 0x400)\r |
| 39 | rendstatus |= PDRAW_DIRTY_SPRITES;\r |
| 40 | break;\r |
| 41 | case 3: Pico.m.dirtyPal = 1;\r |
| 42 | Pico.cram [(a>>1)&0x003f]=d; break; // wraps (Desert Strike)\r |
| 43 | case 5: Pico.vsram[(a>>1)&0x003f]=d; break;\r |
| 44 | //default:elprintf(EL_ANOMALY, "VDP write %04x with bad type %i", d, Pico.video.type); break;\r |
| 45 | }\r |
| 46 | \r |
| 47 | AutoIncrement();\r |
| 48 | }\r |
| 49 | \r |
| 50 | static unsigned int VideoRead(void)\r |
| 51 | {\r |
| 52 | unsigned int a=0,d=0;\r |
| 53 | \r |
| 54 | a=Pico.video.addr; a>>=1;\r |
| 55 | \r |
| 56 | switch (Pico.video.type)\r |
| 57 | {\r |
| 58 | case 0: d=Pico.vram [a&0x7fff]; break;\r |
| 59 | case 8: d=Pico.cram [a&0x003f]; break;\r |
| 60 | case 4: d=Pico.vsram[a&0x003f]; break;\r |
| 61 | default:elprintf(EL_ANOMALY, "VDP read with bad type %i", Pico.video.type); break;\r |
| 62 | }\r |
| 63 | \r |
| 64 | AutoIncrement();\r |
| 65 | return d;\r |
| 66 | }\r |
| 67 | \r |
| 68 | static int GetDmaLength(void)\r |
| 69 | {\r |
| 70 | struct PicoVideo *pvid=&Pico.video;\r |
| 71 | int len=0;\r |
| 72 | // 16-bit words to transfer:\r |
| 73 | len =pvid->reg[0x13];\r |
| 74 | len|=pvid->reg[0x14]<<8;\r |
| 75 | // Charles MacDonald:\r |
| 76 | if(!len) len = 0xffff;\r |
| 77 | return len;\r |
| 78 | }\r |
| 79 | \r |
| 80 | static void DmaSlow(int len)\r |
| 81 | {\r |
| 82 | u16 *pd=0, *pdend, *r;\r |
| 83 | unsigned int a=Pico.video.addr, a2, d;\r |
| 84 | unsigned char inc=Pico.video.reg[0xf];\r |
| 85 | unsigned int source;\r |
| 86 | \r |
| 87 | source =Pico.video.reg[0x15]<<1;\r |
| 88 | source|=Pico.video.reg[0x16]<<9;\r |
| 89 | source|=Pico.video.reg[0x17]<<17;\r |
| 90 | \r |
| 91 | elprintf(EL_VDPDMA, "DmaSlow[%i] %06x->%04x len %i inc=%i blank %i [%i] @ %06x",\r |
| 92 | Pico.video.type, source, a, len, inc, (Pico.video.status&8)||!(Pico.video.reg[1]&0x40),\r |
| 93 | SekCyclesDone(), SekPc);\r |
| 94 | \r |
| 95 | Pico.m.dma_xfers += len;\r |
| 96 | if ((PicoAHW & PAHW_MCD) && (PicoOpt & POPT_EN_MCD_PSYNC)) SekCyclesBurn(CheckDMA());\r |
| 97 | else SekEndTimeslice(SekCyclesLeftNoMCD - CheckDMA());\r |
| 98 | \r |
| 99 | if ((source&0xe00000)==0xe00000) { // Ram\r |
| 100 | pd=(u16 *)(Pico.ram+(source&0xfffe));\r |
| 101 | pdend=(u16 *)(Pico.ram+0x10000);\r |
| 102 | }\r |
| 103 | else if (PicoAHW & PAHW_MCD)\r |
| 104 | {\r |
| 105 | elprintf(EL_VDPDMA, "DmaSlow CD, r3=%02x", Pico_mcd->s68k_regs[3]);\r |
| 106 | if(source<0x20000) { // Bios area\r |
| 107 | pd=(u16 *)(Pico_mcd->bios+(source&~1));\r |
| 108 | pdend=(u16 *)(Pico_mcd->bios+0x20000);\r |
| 109 | } else if ((source&0xfc0000)==0x200000) { // Word Ram\r |
| 110 | source -= 2;\r |
| 111 | if (!(Pico_mcd->s68k_regs[3]&4)) { // 2M mode\r |
| 112 | pd=(u16 *)(Pico_mcd->word_ram2M+(source&0x3fffe));\r |
| 113 | pdend=(u16 *)(Pico_mcd->word_ram2M+0x40000);\r |
| 114 | } else {\r |
| 115 | if (source < 0x220000) { // 1M mode\r |
| 116 | int bank = Pico_mcd->s68k_regs[3]&1;\r |
| 117 | pd=(u16 *)(Pico_mcd->word_ram1M[bank]+(source&0x1fffe));\r |
| 118 | pdend=(u16 *)(Pico_mcd->word_ram1M[bank]+0x20000);\r |
| 119 | } else {\r |
| 120 | DmaSlowCell(source, a, len, inc);\r |
| 121 | return;\r |
| 122 | }\r |
| 123 | }\r |
| 124 | } else if ((source&0xfe0000)==0x020000) { // Prg Ram\r |
| 125 | u8 *prg_ram = Pico_mcd->prg_ram_b[Pico_mcd->s68k_regs[3]>>6];\r |
| 126 | pd=(u16 *)(prg_ram+(source&0x1fffe));\r |
| 127 | pdend=(u16 *)(prg_ram+0x20000);\r |
| 128 | } else {\r |
| 129 | elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow[%i] %06x->%04x: FIXME: unsupported src", Pico.video.type, source, a);\r |
| 130 | return;\r |
| 131 | }\r |
| 132 | }\r |
| 133 | else\r |
| 134 | {\r |
| 135 | // if we have DmaHook, let it handle ROM because of possible DMA delay\r |
| 136 | if (PicoDmaHook && PicoDmaHook(source, len, &pd, &pdend));\r |
| 137 | else if (source<Pico.romsize) { // Rom\r |
| 138 | pd=(u16 *)(Pico.rom+(source&~1));\r |
| 139 | pdend=(u16 *)(Pico.rom+Pico.romsize);\r |
| 140 | }\r |
| 141 | else {\r |
| 142 | elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow[%i] %06x->%04x: invalid src", Pico.video.type, source, a);\r |
| 143 | return;\r |
| 144 | }\r |
| 145 | }\r |
| 146 | \r |
| 147 | // overflow protection, might break something..\r |
| 148 | if (len > pdend - pd) {\r |
| 149 | len = pdend - pd;\r |
| 150 | elprintf(EL_VDPDMA|EL_ANOMALY, "DmaSlow overflow");\r |
| 151 | }\r |
| 152 | \r |
| 153 | switch (Pico.video.type)\r |
| 154 | {\r |
| 155 | case 1: // vram\r |
| 156 | r = Pico.vram;\r |
| 157 | if (inc == 2 && !(a&1) && a+len*2 < 0x10000)\r |
| 158 | {\r |
| 159 | // most used DMA mode\r |
| 160 | memcpy16(r + (a>>1), pd, len);\r |
| 161 | a += len*2;\r |
| 162 | }\r |
| 163 | else\r |
| 164 | {\r |
| 165 | for(; len; len--)\r |
| 166 | {\r |
| 167 | d=*pd++;\r |
| 168 | if(a&1) d=(d<<8)|(d>>8);\r |
| 169 | r[a>>1] = (u16)d; // will drop the upper bits\r |
| 170 | // AutoIncrement\r |
| 171 | a=(u16)(a+inc);\r |
| 172 | // didn't src overlap?\r |
| 173 | //if(pd >= pdend) pd-=0x8000; // should be good for RAM, bad for ROM\r |
| 174 | }\r |
| 175 | }\r |
| 176 | rendstatus |= PDRAW_DIRTY_SPRITES;\r |
| 177 | break;\r |
| 178 | \r |
| 179 | case 3: // cram\r |
| 180 | Pico.m.dirtyPal = 1;\r |
| 181 | r = Pico.cram;\r |
| 182 | for(a2=a&0x7f; len; len--)\r |
| 183 | {\r |
| 184 | r[a2>>1] = (u16)*pd++; // bit 0 is ignored\r |
| 185 | // AutoIncrement\r |
| 186 | a2+=inc;\r |
| 187 | // didn't src overlap?\r |
| 188 | //if(pd >= pdend) pd-=0x8000;\r |
| 189 | // good dest?\r |
| 190 | if(a2 >= 0x80) break; // Todds Adventures in Slime World / Andre Agassi tennis\r |
| 191 | }\r |
| 192 | a=(a&0xff00)|a2;\r |
| 193 | break;\r |
| 194 | \r |
| 195 | case 5: // vsram[a&0x003f]=d;\r |
| 196 | r = Pico.vsram;\r |
| 197 | for(a2=a&0x7f; len; len--)\r |
| 198 | {\r |
| 199 | r[a2>>1] = (u16)*pd++;\r |
| 200 | // AutoIncrement\r |
| 201 | a2+=inc;\r |
| 202 | // didn't src overlap?\r |
| 203 | //if(pd >= pdend) pd-=0x8000;\r |
| 204 | // good dest?\r |
| 205 | if(a2 >= 0x80) break;\r |
| 206 | }\r |
| 207 | a=(a&0xff00)|a2;\r |
| 208 | break;\r |
| 209 | \r |
| 210 | default:\r |
| 211 | elprintf(EL_VDPDMA|EL_ANOMALY, "DMA with bad type %i", Pico.video.type);\r |
| 212 | break;\r |
| 213 | }\r |
| 214 | // remember addr\r |
| 215 | Pico.video.addr=(u16)a;\r |
| 216 | }\r |
| 217 | \r |
| 218 | static void DmaCopy(int len)\r |
| 219 | {\r |
| 220 | u16 a=Pico.video.addr;\r |
| 221 | unsigned char *vr = (unsigned char *) Pico.vram;\r |
| 222 | unsigned char *vrs;\r |
| 223 | unsigned char inc=Pico.video.reg[0xf];\r |
| 224 | int source;\r |
| 225 | elprintf(EL_VDPDMA, "DmaCopy len %i [%i]", len, SekCyclesDone());\r |
| 226 | \r |
| 227 | Pico.m.dma_xfers += len;\r |
| 228 | Pico.video.status |= 2; // dma busy\r |
| 229 | \r |
| 230 | source =Pico.video.reg[0x15];\r |
| 231 | source|=Pico.video.reg[0x16]<<8;\r |
| 232 | vrs=vr+source;\r |
| 233 | \r |
| 234 | if (source+len > 0x10000) len=0x10000-source; // clip??\r |
| 235 | \r |
| 236 | for (; len; len--)\r |
| 237 | {\r |
| 238 | vr[a] = *vrs++;\r |
| 239 | // AutoIncrement\r |
| 240 | a=(u16)(a+inc);\r |
| 241 | }\r |
| 242 | // remember addr\r |
| 243 | Pico.video.addr=a;\r |
| 244 | rendstatus |= PDRAW_DIRTY_SPRITES;\r |
| 245 | }\r |
| 246 | \r |
| 247 | // check: Contra, Megaman\r |
| 248 | // note: this is still inaccurate\r |
| 249 | static void DmaFill(int data)\r |
| 250 | {\r |
| 251 | int len;\r |
| 252 | unsigned short a=Pico.video.addr;\r |
| 253 | unsigned char *vr=(unsigned char *) Pico.vram;\r |
| 254 | unsigned char high = (unsigned char) (data >> 8);\r |
| 255 | unsigned char inc=Pico.video.reg[0xf];\r |
| 256 | \r |
| 257 | len=GetDmaLength();\r |
| 258 | elprintf(EL_VDPDMA, "DmaFill len %i inc %i [%i]", len, inc, SekCyclesDone());\r |
| 259 | \r |
| 260 | Pico.m.dma_xfers += len;\r |
| 261 | Pico.video.status |= 2; // dma busy\r |
| 262 | \r |
| 263 | // from Charles MacDonald's genvdp.txt:\r |
| 264 | // Write lower byte to address specified\r |
| 265 | vr[a] = (unsigned char) data;\r |
| 266 | a=(u16)(a+inc);\r |
| 267 | \r |
| 268 | if (!inc) len=1;\r |
| 269 | \r |
| 270 | for (; len; len--) {\r |
| 271 | // Write upper byte to adjacent address\r |
| 272 | // (here we are byteswapped, so address is already 'adjacent')\r |
| 273 | vr[a] = high;\r |
| 274 | \r |
| 275 | // Increment address register\r |
| 276 | a=(u16)(a+inc);\r |
| 277 | }\r |
| 278 | // remember addr\r |
| 279 | Pico.video.addr=a;\r |
| 280 | // update length\r |
| 281 | Pico.video.reg[0x13] = Pico.video.reg[0x14] = 0; // Dino Dini's Soccer (E) (by Haze)\r |
| 282 | \r |
| 283 | rendstatus |= PDRAW_DIRTY_SPRITES;\r |
| 284 | }\r |
| 285 | \r |
| 286 | static void CommandDma(void)\r |
| 287 | {\r |
| 288 | struct PicoVideo *pvid=&Pico.video;\r |
| 289 | int len=0,method=0;\r |
| 290 | \r |
| 291 | if ((pvid->reg[1]&0x10)==0) return; // DMA not enabled\r |
| 292 | \r |
| 293 | len=GetDmaLength();\r |
| 294 | \r |
| 295 | method=pvid->reg[0x17]>>6;\r |
| 296 | if (method< 2) DmaSlow(len); // 68000 to VDP\r |
| 297 | if (method==3) DmaCopy(len); // VRAM Copy\r |
| 298 | }\r |
| 299 | \r |
| 300 | static void CommandChange(void)\r |
| 301 | {\r |
| 302 | struct PicoVideo *pvid=&Pico.video;\r |
| 303 | unsigned int cmd=0,addr=0;\r |
| 304 | \r |
| 305 | cmd=pvid->command;\r |
| 306 | \r |
| 307 | // Get type of transfer 0xc0000030 (v/c/vsram read/write)\r |
| 308 | pvid->type=(unsigned char)(((cmd>>2)&0xc)|(cmd>>30));\r |
| 309 | \r |
| 310 | // Get address 0x3fff0003\r |
| 311 | addr =(cmd>>16)&0x3fff;\r |
| 312 | addr|=(cmd<<14)&0xc000;\r |
| 313 | pvid->addr=(unsigned short)addr;\r |
| 314 | \r |
| 315 | // Check for dma:\r |
| 316 | if (cmd&0x80) CommandDma();\r |
| 317 | }\r |
| 318 | \r |
| 319 | static void DrawSync(int blank_on)\r |
| 320 | {\r |
| 321 | if (Pico.m.scanline < 224 && !(PicoOpt & POPT_ALT_RENDERER) &&\r |
| 322 | !PicoSkipFrame && DrawScanline <= Pico.m.scanline) {\r |
| 323 | //elprintf(EL_ANOMALY, "sync");\r |
| 324 | PicoDrawSync(Pico.m.scanline, blank_on);\r |
| 325 | }\r |
| 326 | }\r |
| 327 | \r |
| 328 | PICO_INTERNAL_ASM void PicoVideoWrite(unsigned int a,unsigned short d)\r |
| 329 | {\r |
| 330 | struct PicoVideo *pvid=&Pico.video;\r |
| 331 | \r |
| 332 | //if (Pico.m.scanline < 224)\r |
| 333 | // elprintf(EL_STATUS, "PicoVideoWrite [%06x] %04x", a, d);\r |
| 334 | a&=0x1c;\r |
| 335 | \r |
| 336 | if (a==0x00) // Data port 0 or 2\r |
| 337 | {\r |
| 338 | // try avoiding the sync..\r |
| 339 | if (Pico.m.scanline < 224 && (pvid->reg[1]&0x40) &&\r |
| 340 | !(!pvid->pending &&\r |
| 341 | ((pvid->command & 0xc00000f0) == 0x40000010 && Pico.vsram[pvid->addr>>1] == d))\r |
| 342 | )\r |
| 343 | DrawSync(0);\r |
| 344 | \r |
| 345 | if (pvid->pending) {\r |
| 346 | CommandChange();\r |
| 347 | pvid->pending=0;\r |
| 348 | }\r |
| 349 | \r |
| 350 | // If a DMA fill has been set up, do it\r |
| 351 | if ((pvid->command&0x80) && (pvid->reg[1]&0x10) && (pvid->reg[0x17]>>6)==2)\r |
| 352 | {\r |
| 353 | DmaFill(d);\r |
| 354 | }\r |
| 355 | else\r |
| 356 | {\r |
| 357 | // preliminary FIFO emulation for Chaos Engine, The (E)\r |
| 358 | if (!(pvid->status&8) && (pvid->reg[1]&0x40) && !(PicoOpt&POPT_DIS_VDP_FIFO)) // active display?\r |
| 359 | {\r |
| 360 | pvid->status&=~0x200; // FIFO no longer empty\r |
| 361 | pvid->lwrite_cnt++;\r |
| 362 | if (pvid->lwrite_cnt >= 4) pvid->status|=0x100; // FIFO full\r |
| 363 | if (pvid->lwrite_cnt > 4) {\r |
| 364 | SekCyclesBurn(32); // penalty // 488/12-8\r |
| 365 | if (SekCycleCnt>=SekCycleAim) SekEndRun(0);\r |
| 366 | }\r |
| 367 | elprintf(EL_ASVDP, "VDP data write: %04x [%06x] {%i} #%i @ %06x", d, Pico.video.addr,\r |
| 368 | Pico.video.type, pvid->lwrite_cnt, SekPc);\r |
| 369 | }\r |
| 370 | VideoWrite(d);\r |
| 371 | }\r |
| 372 | return;\r |
| 373 | }\r |
| 374 | \r |
| 375 | if (a==0x04) // Control (command) port 4 or 6\r |
| 376 | {\r |
| 377 | if (pvid->pending)\r |
| 378 | {\r |
| 379 | if (d & 0x80) DrawSync(0); // only need sync for DMA\r |
| 380 | // Low word of command:\r |
| 381 | pvid->command&=0xffff0000;\r |
| 382 | pvid->command|=d;\r |
| 383 | pvid->pending=0;\r |
| 384 | CommandChange();\r |
| 385 | }\r |
| 386 | else\r |
| 387 | {\r |
| 388 | if ((d&0xc000)==0x8000)\r |
| 389 | {\r |
| 390 | // Register write:\r |
| 391 | int num=(d>>8)&0x1f;\r |
| 392 | int dold=pvid->reg[num];\r |
| 393 | int blank_on = 0;\r |
| 394 | pvid->type=0; // register writes clear command (else no Sega logo in Golden Axe II)\r |
| 395 | if (num > 0x0a && !(pvid->reg[1]&4)) {\r |
| 396 | elprintf(EL_ANOMALY, "%02x written to reg %02x in SMS mode @ %06x", d, num, SekPc);\r |
| 397 | return;\r |
| 398 | }\r |
| 399 | \r |
| 400 | if (num == 1 && !(d&0x40) && SekCyclesLeft > 390) blank_on = 1;\r |
| 401 | DrawSync(blank_on);\r |
| 402 | pvid->reg[num]=(unsigned char)d;\r |
| 403 | switch (num)\r |
| 404 | {\r |
| 405 | case 0x00:\r |
| 406 | elprintf(EL_INTSW, "hint_onoff: %i->%i [%i] pend=%i @ %06x", (dold&0x10)>>4,\r |
| 407 | (d&0x10)>>4, SekCyclesDone(), (pvid->pending_ints&0x10)>>4, SekPc);\r |
| 408 | goto update_irq;\r |
| 409 | case 0x01:\r |
| 410 | elprintf(EL_INTSW, "vint_onoff: %i->%i [%i] pend=%i @ %06x", (dold&0x20)>>5,\r |
| 411 | (d&0x20)>>5, SekCyclesDone(), (pvid->pending_ints&0x20)>>5, SekPc);\r |
| 412 | goto update_irq;\r |
| 413 | case 0x05:\r |
| 414 | //elprintf(EL_STATUS, "spritep moved to %04x", (unsigned)(Pico.video.reg[5]&0x7f) << 9);\r |
| 415 | if (d^dold) rendstatus |= PDRAW_SPRITES_MOVED;\r |
| 416 | break;\r |
| 417 | case 0x0c:\r |
| 418 | // renderers should update their palettes if sh/hi mode is changed\r |
| 419 | if ((d^dold)&8) Pico.m.dirtyPal = 2;\r |
| 420 | break;\r |
| 421 | }\r |
| 422 | return;\r |
| 423 | \r |
| 424 | update_irq:\r |
| 425 | #ifndef EMU_CORE_DEBUG\r |
| 426 | // update IRQ level\r |
| 427 | if (!SekShouldInterrupt) // hack\r |
| 428 | {\r |
| 429 | int lines, pints, irq=0;\r |
| 430 | lines = (pvid->reg[1] & 0x20) | (pvid->reg[0] & 0x10);\r |
| 431 | pints = (pvid->pending_ints&lines);\r |
| 432 | if (pints & 0x20) irq = 6;\r |
| 433 | else if (pints & 0x10) irq = 4;\r |
| 434 | SekInterrupt(irq); // update line\r |
| 435 | \r |
| 436 | if (irq) SekEndRun(24); // make it delayed\r |
| 437 | }\r |
| 438 | #endif\r |
| 439 | }\r |
| 440 | else\r |
| 441 | {\r |
| 442 | // High word of command:\r |
| 443 | pvid->command&=0x0000ffff;\r |
| 444 | pvid->command|=d<<16;\r |
| 445 | pvid->pending=1;\r |
| 446 | }\r |
| 447 | }\r |
| 448 | }\r |
| 449 | }\r |
| 450 | \r |
| 451 | PICO_INTERNAL_ASM unsigned int PicoVideoRead(unsigned int a)\r |
| 452 | {\r |
| 453 | a&=0x1c;\r |
| 454 | \r |
| 455 | if (a==0x04) // control port\r |
| 456 | {\r |
| 457 | struct PicoVideo *pv=&Pico.video;\r |
| 458 | unsigned int d;\r |
| 459 | d=pv->status;\r |
| 460 | //if (PicoOpt&POPT_ALT_RENDERER) d|=0x0020; // sprite collision (Shadow of the Beast)\r |
| 461 | if (SekCyclesLeft < 84+4) d|=0x0004; // H-Blank (Sonic3 vs)\r |
| 462 | \r |
| 463 | d |= ((pv->reg[1]&0x40)^0x40) >> 3; // set V-Blank if display is disabled\r |
| 464 | d |= (pv->pending_ints&0x20)<<2; // V-int pending?\r |
| 465 | if (d&0x100) pv->status&=~0x100; // FIFO no longer full\r |
| 466 | \r |
| 467 | pv->pending = 0; // ctrl port reads clear write-pending flag (Charles MacDonald)\r |
| 468 | \r |
| 469 | elprintf(EL_SR, "SR read: %04x @ %06x", d, SekPc);\r |
| 470 | return d;\r |
| 471 | }\r |
| 472 | \r |
| 473 | // H-counter info (based on Generator):\r |
| 474 | // frame:\r |
| 475 | // | <- hblank? -> |\r |
| 476 | // start <416> hint <36> hdisplay <38> end // CPU cycles\r |
| 477 | // |---------...---------|------------|-------------|\r |
| 478 | // 0 B6 E4 FF // 40 cells\r |
| 479 | // 0 93 E8 FF // 32 cells\r |
| 480 | \r |
| 481 | // Gens (?) v-render\r |
| 482 | // start <hblank=84> hint hdisplay <404> |\r |
| 483 | // |---------------------|--------------------------|\r |
| 484 | // E4 (hc[0x43]==0) 07 B1 // 40\r |
| 485 | // E8 (hc[0x45]==0) 05 91 // 32\r |
| 486 | \r |
| 487 | // check: Sonic 3D Blast bonus, Cannon Fodder, Chase HQ II, 3 Ninjas kick back, Road Rash 3, Skitchin', Wheel of Fortune\r |
| 488 | if ((a&0x1c)==0x08)\r |
| 489 | {\r |
| 490 | unsigned int d;\r |
| 491 | int lineCycles;\r |
| 492 | \r |
| 493 | lineCycles = (488-SekCyclesLeft)&0x1ff;\r |
| 494 | if (Pico.video.reg[12]&1)\r |
| 495 | d = hcounts_40[lineCycles];\r |
| 496 | else d = hcounts_32[lineCycles];\r |
| 497 | \r |
| 498 | elprintf(EL_HVCNT, "hv: %02x %02x (%i) @ %06x", d, Pico.video.v_counter, SekCyclesDone(), SekPc);\r |
| 499 | return d | (Pico.video.v_counter << 8);\r |
| 500 | }\r |
| 501 | \r |
| 502 | if (a==0x00) // data port\r |
| 503 | {\r |
| 504 | return VideoRead();\r |
| 505 | }\r |
| 506 | \r |
| 507 | return 0;\r |
| 508 | }\r |
| 509 | \r |
| 510 | unsigned int PicoVideoRead8(unsigned int a)\r |
| 511 | {\r |
| 512 | unsigned int d;\r |
| 513 | a&=0x1d;\r |
| 514 | \r |
| 515 | switch (a)\r |
| 516 | {\r |
| 517 | case 0: return VideoRead() >> 8;\r |
| 518 | case 1: return VideoRead() & 0xff;\r |
| 519 | case 4: // control port/status reg\r |
| 520 | d = Pico.video.status >> 8;\r |
| 521 | if (d&1) Pico.video.status&=~0x100; // FIFO no longer full\r |
| 522 | Pico.video.pending = 0;\r |
| 523 | elprintf(EL_SR, "SR read (h): %02x @ %06x", d, SekPc);\r |
| 524 | return d;\r |
| 525 | case 5:\r |
| 526 | d = Pico.video.status & 0xff;\r |
| 527 | //if (PicoOpt&POPT_ALT_RENDERER) d|=0x0020; // sprite collision (Shadow of the Beast)\r |
| 528 | d |= ((Pico.video.reg[1]&0x40)^0x40) >> 3; // set V-Blank if display is disabled\r |
| 529 | d |= (Pico.video.pending_ints&0x20)<<2; // V-int pending?\r |
| 530 | if (SekCyclesLeft < 84+4) d |= 4; // H-Blank\r |
| 531 | Pico.video.pending = 0;\r |
| 532 | elprintf(EL_SR, "SR read (l): %02x @ %06x", d, SekPc);\r |
| 533 | return d;\r |
| 534 | case 8: // hv counter\r |
| 535 | elprintf(EL_HVCNT, "vcounter: %02x (%i) @ %06x", Pico.video.v_counter, SekCyclesDone(), SekPc);\r |
| 536 | return Pico.video.v_counter;\r |
| 537 | case 9:\r |
| 538 | d = (488-SekCyclesLeft)&0x1ff;\r |
| 539 | if (Pico.video.reg[12]&1)\r |
| 540 | d = hcounts_40[d];\r |
| 541 | else d = hcounts_32[d];\r |
| 542 | elprintf(EL_HVCNT, "hcounter: %02x (%i) @ %06x", d, SekCyclesDone(), SekPc);\r |
| 543 | return d;\r |
| 544 | }\r |
| 545 | \r |
| 546 | return 0;\r |
| 547 | }\r |