Example #1
0
static void PicoLinePico(void)
{
  PicoPicohw.line_counter++;

#if 1
  if ((PicoPicohw.r12 & 0x4003) && PicoPicohw.line_counter - prev_line_cnt_irq3 > 200) {
    prev_line_cnt_irq3 = PicoPicohw.line_counter;
    // just a guess/hack, allows 101 Dalmantians to boot
    elprintf(EL_PICOHW, "irq3");
    SekInterrupt(3);
    return;
  }
#endif

  if (PicoPicohw.fifo_bytes > 0)
  {
    PicoPicohw.fifo_line_bytes += fifo_bytes_line;
    if (PicoPicohw.fifo_line_bytes >= (1<<16)) {
      PicoPicohw.fifo_bytes -= PicoPicohw.fifo_line_bytes >> 16;
      PicoPicohw.fifo_line_bytes &= 0xffff;
      if (PicoPicohw.fifo_bytes < 0)
        PicoPicohw.fifo_bytes = 0;
    }
// Accurate but slower frame which does hints
static int PicoFrameHints(void)
{
  struct PicoVideo *pv=&Pico.video;
  int lines, y, lines_vis = 224, total_z80 = 0, z80CycleAim = 0, line_sample, skip;
  int hint; // Hint counter

  if ((PicoOpt&0x10) && !PicoSkipFrame) {
    // draw a frame just after vblank in alternative render mode
    // yes, this will cause 1 frame lag, but this is inaccurate mode anyway.
    PicoFrameFull();
#ifdef DRAW_FINISH_FUNC
    DRAW_FINISH_FUNC();
#endif
    skip = 1;
  }
  else skip=PicoSkipFrame;

  if (Pico.m.pal) {
    //cycles_68k = (int) ((double) OSC_PAL  /  7 / 50 / 312 + 0.4); // should compile to a constant (488)
    //cycles_z80 = (int) ((double) OSC_PAL  / 15 / 50 / 312 + 0.4); // 228
    line_sample = 68;
    if(pv->reg[1]&8) lines_vis = 240;
  } else {
    //cycles_68k = (int) ((double) OSC_NTSC /  7 / 60 / 262 + 0.4); // 488
    //cycles_z80 = (int) ((double) OSC_NTSC / 15 / 60 / 262 + 0.4); // 228
    line_sample = 93;
  }

  SekCyclesReset();
#ifdef PICO_CD
  SekCyclesResetS68k();
#endif

  pv->status&=~0x88; // clear V-Int, come out of vblank

  hint=pv->reg[10]; // Load H-Int counter
  //dprintf("-hint: %i", hint);

  // This is to make active scan longer (needed for Double Dragon 2, mainly)
  // also trying to adjust for z80 overclock here (due to int line cycle counts)
  z80CycleAim = Pico.m.pal ? -40 : 7;
  CPUS_RUN(CYCLES_M68K_ASD, 0, CYCLES_S68K_ASD);

  for (y=0;y<lines_vis;y++)
  {
    Pico.m.scanline=(short)y;

    // VDP FIFO
    pv->lwrite_cnt -= 12;
    if (pv->lwrite_cnt <= 0) {
      pv->lwrite_cnt=0;
      Pico.video.status|=0x200;
    }

    PAD_DELAY
#ifdef PICO_CD
    check_cd_dma();
#endif

    // H-Interrupts:
    if (--hint < 0) // y <= lines_vis: Comix Zone, Golden Axe
    {
      hint=pv->reg[10]; // Reload H-Int counter
      pv->pending_ints|=0x10;
      if (pv->reg[0]&0x10) {
        elprintf(EL_INTS, "hint: @ %06x [%i]", SekPc, SekCycleCnt);
        SekInterrupt(4);
      }
    }

    // decide if we draw this line
#if CAN_HANDLE_240_LINES
    if(!skip && ((!(pv->reg[1]&8) && y<224) || (pv->reg[1]&8)) )
#else
    if(!skip && y<224)
#endif
      PicoLine(y);

    /*if(PicoOpt&1)
      Psnd_timers_and_dac(y);*/

#ifndef PICO_CD
    // get samples from sound chips
    if(y == 32/* && PsndOut*/)
      emustatus &= ~1;
    else if((y == 224 || y == line_sample)/* && PsndOut*/)
      getSamples(y);
#endif

    // Run scanline:
    if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
    CPUS_RUN(CYCLES_M68K_LINE, CYCLES_Z80_LINE, CYCLES_S68K_LINE);

#ifdef PICO_CD
    update_chips();
#endif
  }

#ifdef DRAW_FINISH_FUNC
  if (!skip)
    DRAW_FINISH_FUNC();
#endif

  // V-int line (224 or 240)
  Pico.m.scanline=(short)y;

  // VDP FIFO
  pv->lwrite_cnt=0;
  Pico.video.status|=0x200;

  PAD_DELAY
#ifdef PICO_CD
  check_cd_dma();
#endif

  // Last H-Int:
  if (--hint < 0)
  {
    hint=pv->reg[10]; // Reload H-Int counter
    pv->pending_ints|=0x10;
    //printf("rhint: %i @ %06x [%i|%i]\n", hint, SekPc, y, SekCycleCnt);
    if (pv->reg[0]&0x10) SekInterrupt(4);
  }

  // V-Interrupt:
  pv->status|=0x08; // go into vblank
  pv->pending_ints|=0x20;

  // the following SekRun is there for several reasons:
  // there must be a delay after vblank bit is set and irq is asserted (Mazin Saga)
  // also delay between F bit (bit 7) is set in SR and IRQ happens (Ex-Mutants)
  // also delay between last H-int and V-int (Golden Axe 3)
  SekRunM68k(CYCLES_M68K_VINT_LAG);
  if (pv->reg[1]&0x20) {
    elprintf(EL_INTS, "vint: @ %06x [%i]", SekPc, SekCycleCnt);
    SekInterrupt(6);
  }
  if (Pico.m.z80Run && (PicoOpt&4))
    z80_int();

  /*if (PicoOpt&1)
    Psnd_timers_and_dac(y);*/

  // get samples from sound chips
#ifndef PICO_CD
  if (y == 224)
#endif
   /* if (PsndOut)
      getSamples(y);*/

  // Run scanline:
  if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
  CPUS_RUN(CYCLES_M68K_LINE - CYCLES_M68K_VINT_LAG - CYCLES_M68K_ASD,
    CYCLES_Z80_LINE - CYCLES_Z80_ASD, CYCLES_S68K_LINE - CYCLES_S68K_ASD);

#ifdef PICO_CD
    update_chips();
#endif

  // PAL line count might actually be 313 according to Steve Snake, but that would complicate things.
  lines = Pico.m.pal ? 312 : 262;

  for (y++;y<lines;y++)
  {
    Pico.m.scanline=(short)y;

    PAD_DELAY
#ifdef PICO_CD
    check_cd_dma();
#endif

    /*if(PicoOpt&1)
      Psnd_timers_and_dac(y);*/

    // Run scanline:
    if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
    CPUS_RUN(CYCLES_M68K_LINE, CYCLES_Z80_LINE, CYCLES_S68K_LINE);

#ifdef PICO_CD
    update_chips();
#endif
  }

  return 0;
}