u32 z80ReadBusReq(void)
{
u32 d=Pico.m.z80Run&1;
- if (!d) {
+ if (!d && Pico.m.scanline != -1) {
// needed by buggy Terminator (Sega CD)
int stop_before = SekCyclesDone() - z80stopCycle;
- dprintf("stop before: %i", stop_before);
- if (stop_before > 0 && stop_before <= 32) // Gens uses 16 here
+ //elprintf(EL_BUSREQ, "get_zrun: stop before: %i", stop_before);
+ // note: if we use 20 or more here, Barkley Shut Up and Jam! will purposedly crash itself.
+ // TODO: CD Terminator
+ if (stop_before > 0 && stop_before < 20) // Gens uses 16 here
d = 1; // bus not yet available
}
// |=0x80 for Shadow of the Beast & Super Offroad
+ elprintf(EL_BUSREQ, "get_zrun: %02x [%i] @%06x", d|0x80, SekCyclesDone(), SekPc);
return d|0x80;
}
void z80WriteBusReq(u32 d)
{
d&=1; d^=1;
- if(!d) {
- // this is for a nasty situation where Z80 was enabled and disabled in the same 68k timeslice (Golden Axe III)
- if (Pico.m.z80Run) {
- int lineCycles;
- z80stopCycle = SekCyclesDone();
- if (Pico.m.z80Run&2)
- lineCycles=(488-SekCyclesLeft)&0x1ff;
- else lineCycles=z80stopCycle-z80startCycle; // z80 was started at current line
- if (lineCycles > 0 && lineCycles <= 488) {
- dprintf("zrun: %i/%i cycles", lineCycles, (lineCycles>>1)-(lineCycles>>5));
- lineCycles=(lineCycles>>1)-(lineCycles>>5);
- z80_run(lineCycles);
+ if (Pico.m.scanline != -1)
+ {
+ if(!d) {
+ // this is for a nasty situation where Z80 was enabled and disabled in the same 68k timeslice (Golden Axe III)
+ if (Pico.m.z80Run) {
+ int lineCycles;
+ z80stopCycle = SekCyclesDone();
+ if (Pico.m.z80Run&2)
+ lineCycles=(488-SekCyclesLeft)&0x1ff;
+ else lineCycles=z80stopCycle-z80startCycle; // z80 was started at current line
+ if (lineCycles > 0 && lineCycles <= 488) {
+ //dprintf("zrun: %i/%i cycles", lineCycles, (lineCycles>>1)-(lineCycles>>5));
+ lineCycles=(lineCycles>>1)-(lineCycles>>5);
+ z80_run(lineCycles);
+ }
}
+ } else {
+ if (!Pico.m.z80Run)
+ z80startCycle = SekCyclesDone();
+ else
+ d|=Pico.m.z80Run;
}
- } else {
- z80startCycle = SekCyclesDone();
- //if(Pico.m.scanline != -1)
}
- dprintf("set_zrun: %02x [%i|%i] @%06x", d, Pico.m.scanline, SekCyclesDone(), /*mz80GetRegisterValue(NULL, 0),*/ SekPc);
+ elprintf(EL_BUSREQ, "set_zrun: %i->%i [%i] @%06x", Pico.m.z80Run, d, SekCyclesDone(), SekPc);
Pico.m.z80Run=(u8)d;
}
goto end;
}
- // |=0x80 for Shadow of the Beast & Super Offroad; rotate fakes next fetched instruction for Time Killers
+ // rotate fakes next fetched instruction for Time Killers
if (a==0xa11100) { // z80 busreq
d=(z80ReadBusReq()<<8)|Pico.m.rotate++;
- dprintf("get_zrun: %04x [%i|%i] @%06x", d, Pico.m.scanline, SekCyclesDone(), SekPc);
goto end;
}
if ((a&0x6000)==0x4000) { // 0x4000-0x5fff, Fudge if disabled
if(PicoOpt&1) d=YM2612Read();
else d=Pico.m.rotate++&3;
- dprintf("read ym2612: %04x", d);
+ elprintf(EL_YM2612R, "read ym2612: %02x", d);
goto end;
}
d=0xffff;
}
#endif
if ((a&0xe700e0)==0xc00000) {
+ d&=0xff;
PicoVideoWrite(a,(u16)(d|(d<<8))); // Byte access gets mirrored
return;
}
return;
}
+#ifndef _CD_MEMORY_C
+ if (a >= SRam.start && a <= SRam.end) {
+ if ((a&0x16)==0x10) { // detected, not EEPROM, write not disabled
+ u8 *pm=(u8 *)(SRam.data-SRam.start+a);
+ *pm++=d>>8;
+ *pm++=d;
+ SRam.changed = 1;
+ }
+ else
+ SRAMWrite(a, d); // ??
+ return;
+ }
+#else
OtherWrite8End(a, d>>8, 16);
OtherWrite8End(a+1,d&0xff, 16);
+#endif
}