initial import

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@2 be3aeb3a-fb24-0410-a615-afba39da0efa

Pico/cd/Pico.c

@@ -0,0 +1,213 @@
+// This is part of Pico Library
+
+// (c) Copyright 2004 Dave, All rights reserved.
+// (c) Copyright 2006 notaz, All rights reserved.
+// Free for non-commercial use.
+
+// For commercial use, separate licencing terms must be obtained.
+
+
+#include "../PicoInt.h"
+#include "../sound/sound.h"
+
+
+int counter75hz = 0;
+
+
+int PicoInitMCD(void)
+{
+  SekInitS68k();
+  Init_CD_Driver();
+
+  return 0;
+}
+
+
+void PicoExitMCD(void)
+{
+  End_CD_Driver();
+}
+
+int PicoResetMCD(int hard)
+{
+  // clear everything except BIOS
+  memset(Pico_mcd->prg_ram, 0, sizeof(mcd_state) - sizeof(Pico_mcd->bios));
+  PicoMCD |= 2; // s68k reset pending
+  counter75hz = 0;
+
+  LC89510_Reset();
+  Reset_CD();
+
+  return 0;
+}
+
+static __inline void SekRun(int cyc)
+{
+  int cyc_do;
+  SekCycleAim+=cyc;
+  if((cyc_do=SekCycleAim-SekCycleCnt) < 0) return;
+#if defined(EMU_M68K)
+  m68k_set_context(&PicoM68kCPU);
+  SekCycleCnt+=m68k_execute(cyc_do);
+#endif
+}
+
+static __inline void SekRunS68k(int cyc)
+{
+  int cyc_do;
+  SekCycleAimS68k+=cyc;
+  if((cyc_do=SekCycleAimS68k-SekCycleCntS68k) < 0) return;
+#if defined(EMU_M68K)
+  m68k_set_context(&PicoS68kCPU);
+  SekCycleCntS68k+=m68k_execute(cyc_do);
+#endif
+}
+
+// TODO: tidy
+extern unsigned char m68k_regs[0x40];
+extern unsigned char s68k_regs[0x200];
+
+// Accurate but slower frame which does hints
+static int PicoFrameHintsMCD(void)
+{
+  struct PicoVideo *pv=&Pico.video;
+  int total_z80=0,lines,y,lines_vis = 224,z80CycleAim = 0,line_sample;
+  const int cycles_68k=488,cycles_z80=228,cycles_s68k=795; // both PAL and NTSC compile to same values
+  int skip=PicoSkipFrame || (PicoOpt&0x10);
+  int hint; // Hint counter
+
+  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
+    lines  = 312;    // Steve Snake says there are 313 lines, but this seems to also work well
+    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
+    lines  = 262;
+    line_sample = 93;
+  }
+
+  SekCyclesReset();
+  SekCyclesResetS68k();
+  //z80ExtraCycles = 0;
+
+  if(PicoOpt&4)
+    z80CycleAim = 0;
+//    z80_resetCycles();
+
+  pv->status&=~0x88; // clear V-Int, come out of vblank
+
+  hint=pv->reg[10]; // Load H-Int counter
+  //dprintf("-hint: %i", hint);
+
+  for (y=0;y<lines;y++)
+  {
+    Pico.m.scanline=(short)y;
+
+    // pad delay (for 6 button pads)
+    if(PicoOpt&0x20) {
+      if(Pico.m.padDelay[0]++ > 25) Pico.m.padTHPhase[0]=0;
+      if(Pico.m.padDelay[1]++ > 25) Pico.m.padTHPhase[1]=0;
+    }
+
+    // H-Interrupts:
+    if(y <= lines_vis && --hint < 0) // y <= lines_vis: Comix Zone, Golden Axe
+    {
+      //dprintf("rhint:old @ %06x", SekPc);
+      hint=pv->reg[10]; // Reload H-Int counter
+      pv->pending_ints|=0x10;
+      if (pv->reg[0]&0x10) SekInterrupt(4);
+      //dprintf("rhint: %i @ %06x [%i|%i]", hint, SekPc, y, SekCycleCnt);
+      //dprintf("hint_routine: %x", (*(unsigned short*)(Pico.ram+0x0B84)<<16)|*(unsigned short*)(Pico.ram+0x0B86));
+    }
+
+    // V-Interrupt:
+    if (y == lines_vis)
+    {
+      //dprintf("vint: @ %06x [%i|%i]", SekPc, y, SekCycleCnt);
+      pv->status|=0x88; // V-Int happened, go into vblank
+      SekRun(128); SekCycleAim-=128; // there must be a gap between H and V ints, also after vblank bit set (Mazin Saga, Bram Stoker's Dracula)
+      /*if(Pico.m.z80Run && (PicoOpt&4)) {
+        z80CycleAim+=cycles_z80/2;
+        total_z80+=z80_run(z80CycleAim-total_z80);
+        z80CycleAim-=cycles_z80/2;
+      }*/
+      pv->pending_ints|=0x20;
+      if(pv->reg[1]&0x20) SekInterrupt(6);
+      if(Pico.m.z80Run && (PicoOpt&4)) // ?
+        z80_int();
+      //dprintf("zint: [%i|%i] zPC=%04x", Pico.m.scanline, SekCyclesDone(), mz80GetRegisterValue(NULL, 0));
+    }
+
+    // decide if we draw this line
+#if CAN_HANDLE_240_LINES
+    if(!skip && ((!(pv->reg[1]&8) && y<224) || ((pv->reg[1]&8) && y<240)) )
+#else
+    if(!skip && y<224)
+#endif
+      PicoLine(y);
+
+    if(PicoOpt&1)
+      sound_timers_and_dac(y);
+
+    // get samples from sound chips
+    if(y == 32 && PsndOut)
+      emustatus &= ~1;
+    else if((y == 224 || y == line_sample) && PsndOut)
+      ;//getSamples(y);
+
+    // Run scanline:
+      //dprintf("m68k starting exec @ %06x", SekPc);
+    SekRun(cycles_68k);
+    if ((Pico_mcd->m68k_regs[1]&3) == 1) { // no busreq/no reset
+#if 0
+	    int i;
+	    FILE *f = fopen("prg_ram.bin", "wb");
+	    for (i = 0; i < 0x80000; i+=2)
+	    {
+		    int tmp = Pico_mcd->prg_ram[i];
+		    Pico_mcd->prg_ram[i] = Pico_mcd->prg_ram[i+1];
+		    Pico_mcd->prg_ram[i+1] = tmp;
+	    }
+	    fwrite(Pico_mcd->prg_ram, 1, 0x80000, f);
+	    fclose(f);
+	    exit(1);
+#endif
+      //dprintf("s68k starting exec @ %06x", SekPcS68k);
+      SekRunS68k(cycles_s68k);
+    }
+
+    if((PicoOpt&4) && Pico.m.z80Run) {
+      Pico.m.z80Run|=2;
+      z80CycleAim+=cycles_z80;
+      total_z80+=z80_run(z80CycleAim-total_z80);
+    }
+
+    // if cdd is on, counter elapsed and irq4 is not masked, do irq4
+    if ((Pico_mcd->s68k_regs[0x37]&4) && ++counter75hz > 209 && (Pico_mcd->s68k_regs[0x33]&(1<<4))) {
+      counter75hz = 0;
+      Check_CD_Command();
+    }
+  }
+
+  // draw a frame just after vblank in alternative render mode
+  if(!PicoSkipFrame && (PicoOpt&0x10))
+    PicoFrameFull();
+
+  return 0;
+}
+
+
+int PicoFrameMCD(void)
+{
+  if(!(PicoOpt&0x10))
+    PicoFrameStart();
+
+  PicoFrameHintsMCD();
+
+  return 0;
+}
+
+