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nes-pass 10-even_odd_timing and 05-nmi_timing

This commit is contained in:
zeromus 2012-03-18 18:41:45 +00:00
parent 44daaa0841
commit 1c7fdf7529
3 changed files with 17 additions and 27 deletions
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2
BizHawk.Emulation/Consoles/Nintendo/NES/PPU.cs
View File

@ -147,8 +147,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
for (int i = 0; i < x; i++)
{
ppur.status.cycle++;
if (ppur.status.cycle == ppur.status.end_cycle)
ppur.status.cycle = 0;
//might not actually run a cpu cycle if there are none to be run right now
nes.RunCpuOne();

6
BizHawk.Emulation/Consoles/Nintendo/NES/PPU.regs.cs
View File

@ -66,7 +66,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
{
public int sl;
public bool rendering { get { return sl >= 0 && sl < 241; } }
public int cycle, end_cycle;
public int cycle;
}
//uses the internal counters concept at http://nesdev.icequake.net/PPU%20addressing.txt
@ -94,7 +94,8 @@ namespace BizHawk.Emulation.Consoles.Nintendo
ser.Sync("_ht", ref _ht);
ser.Sync("fh", ref fh);
ser.Sync("status.cycle", ref status.cycle);
ser.Sync("status.end_cycle", ref status.end_cycle);
int junk = 0;
ser.Sync("status.end_cycle", ref junk);
ser.Sync("status.sl", ref status.sl);
}
@ -151,7 +152,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
fh = 0;
_fv = _v = _h = _vt = _ht = 0;
status.cycle = 0;
status.end_cycle = 341;
status.sl = 241;
}

36
BizHawk.Emulation/Consoles/Nintendo/NES/PPU.run.cs
View File

@ -97,11 +97,12 @@ namespace BizHawk.Emulation.Consoles.Nintendo
//NOTE: Not having this here breaks a Super Donkey Kong game.
reg_2003 = 0;
//fceu/fceux had 12 here, but 15 was required to pass blargg's 05-nmi_timing.nes
const int delay = 15;
//this was repeatedly finetuned from the fceux days thrugh the old cpu core and into the new one to pass 05-nmi_timing.nes
//note that there is still some leniency. for instance, 4,2 will pass in addition to 3,3
const int delay = 6;
runppu(3);
bool nmi_destiny = reg_2000.vblank_nmi_gen && Reg2002_vblank_active;
runppu(delay - 3);
runppu(3);
if (nmi_destiny) TriggerNMI();
if (PAL)
runppu(70 * (kLineTime) - delay);
@ -116,6 +117,8 @@ namespace BizHawk.Emulation.Consoles.Nintendo
int oamslot=0;
int oamcount=0;
idleSynch ^= true;
//render 241 scanlines (including 1 dummy at beginning)
for (int sl = 0; sl < 241; sl++)
{
@ -422,35 +425,24 @@ namespace BizHawk.Emulation.Consoles.Nintendo
ppuphase = PPUPHASE.BG;
//I'm unclear of the reason why this particular access to memory is made.
//The nametable address that is accessed 2 times in a row here, is also the
//same nametable address that points to the 3rd tile to be rendered on the
//screen (or basically, the first nametable address that will be accessed when
//the PPU is fetching background data on the next scanline).
//(not implemented yet)
if (sl == 0)
{
if (idleSynch && reg_2001.show_bg && !PAL)
ppur.status.end_cycle = 340;
else
ppur.status.end_cycle = 341;
idleSynch ^= true;
}
else
ppur.status.end_cycle = 341;
//fetch BG: two tiles for next line
for (int xt = 0; xt < 2; xt++)
Read_bgdata(ref bgdata[xt]);
runppu(kFetchTime * 2);
//this sequence is tuned to pass 10-even_odd_timing.nes
runppu(kFetchTime);
bool evenOddDestiny = reg_2001.show_bg;
runppu(kFetchTime);
//After memory access 170, the PPU simply rests for 4 cycles (or the
//equivelant of half a memory access cycle) before repeating the whole
//pixel/scanline rendering process. If the scanline being rendered is the very
//first one on every second frame, then this delay simply doesn't exist.
if (ppur.status.end_cycle == 341)
if (sl == 0 && idleSynch && evenOddDestiny && !PAL)
{ }
else
runppu(1);
ppur.status.cycle = 0;
} //scanline loop