[NES] fix broken scroll and shaky statusbars regression

BizHawk.Emulation/Consoles/Nintendo/NES/Boards/ExROM.cs

@@ -403,6 +403,8 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 		{
 			if (NES.ppu.ppur.status.cycle != 336)
 				return;
+			if (!NES.ppu.reg_2001.PPUON)
+				return;
 
 			int sl = NES.ppu.ppur.status.sl + 1;
 

BizHawk.Emulation/Consoles/Nintendo/NES/PPU.cs

@@ -25,8 +25,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			//when the ppu issues a read it goes through here and into the game board
 			public byte ppubus_read(int addr, bool ppu)
 			{
-				//speculative -- hardware doesnt touch the bus when the PPU is disabled
+				//hardware doesnt touch the bus when the PPU is disabled
-				//(without this, smb3 title screen creates garbage when skipped)
 				if (!reg_2001.PPUON && ppu)
 					return 0xFF;
 
@@ -155,7 +154,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			//hack
 			public bool PAL = false;
 			bool SPRITELIMIT = true;
-			const int MAXSPRITES = 8;
 
 	
 		}

BizHawk.Emulation/Consoles/Nintendo/NES/PPU.regs.cs

@@ -20,7 +20,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 	{
 		partial class PPU
 		{
-			class Reg_2001
+			public class Reg_2001
 			{
 				public Bit color_disable; //Color disable (0: normal color; 1: AND all palette entries with 110000, effectively producing a monochrome display)
 				public Bit show_bg_leftmost; //Show leftmost 8 pixels of background
@@ -298,7 +298,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			bool Reg2002_vblank_clear_pending; //ppu's clear of vblank flag is pending
 			public PPUREGS ppur;
 			public Reg_2000 reg_2000;
-			Reg_2001 reg_2001;
+			public Reg_2001 reg_2001;
 			byte reg_2003;
 			void regs_reset()
 			{
@@ -387,11 +387,13 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 				{
 					ppur._ht= value >> 3;
 					ppur.fh = value & 7;
+					//nes.LogLine("scroll wrote ht = {0} and fh = {1}", ppur._ht, ppur.fh);
 				}
 				else
 				{
 					ppur._vt = value >> 3;
 					ppur._fv = value & 7;
+					//nes.LogLine("scroll wrote vt = {0} and fv = {1}", ppur._vt, ppur._fv);
 				}
 				vtoggle ^= true;
 			}
@@ -407,6 +409,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					ppur._h = (value >> 2) & 1;
 					ppur._v = (value >> 3) & 1;
 					ppur._fv = (value >> 4) & 3;
+					//nes.LogLine("scroll wrote fv = {0}", ppur._fv);
 				}
 				else
 				{
@@ -414,6 +417,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					ppur._vt |= (value >> 5);
 					ppur._ht = value & 31;
 					ppur.install_latches();
+					//nes.LogLine("scroll wrote vt = {0}, ht = {1}", ppur._vt, ppur._ht);
 
 					nes.board.AddressPPU(ppur.get_2007access());
 				}

BizHawk.Emulation/Consoles/Nintendo/NES/PPU.run.cs

@@ -119,12 +119,11 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 				//render 241 scanlines (including 1 dummy at beginning)
 				for (int sl = 0; sl < 241; sl++)
 				{
-					//TODO - correctly emulate PPU OFF state
+					//if (!reg_2001.PPUON)
-					if (!reg_2001.PPUON)
+					//{
-					{
+					//    runppu(kLineTime);
-						runppu(kLineTime);
+					//    continue;
-						continue;
+					//}
-					}
 
 					ppur.status.sl = sl;
 
@@ -211,10 +210,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 											//1. is it sprite#0?
 											//2. is the bg pixel nonzero?
 											//then, it is spritehit.
-											if (oam->index == 0)
-											{
-												int zzz = 9;
-											}
 											if (oam->index == 0 && pixel != 0 && rasterpos < 255)
 											{
 												Reg2002_objhit = true;
@@ -239,7 +234,9 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 
 								}//oamcount loop
 
+								if (reg_2001.PPUON)
 									xbuf[target] = PaletteAdjustPixel(pixelcolor);
+
 								target++;
 
 							} //loop across 8 pixels
@@ -292,17 +289,20 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 					ppuphase = PPUPHASE.OBJ;
 
 					//fetch sprite patterns
-					for (int s = 0; s < MAXSPRITES; s++)
+					int oam_todo = oamcount;
+					if (oam_todo < 8)
+						oam_todo = 8;
+					for (int s = 0; s < oam_todo; s++)
 					{
-						//if we have hit our eight sprite pattern and we dont have any more sprites, then bail
-						if (s == oamcount && s >= 8)
-							break;
-
 						//if this is a real sprite sprite, then it is not above the 8 sprite limit.
 						//this is how we support the no 8 sprite limit feature.
 						//not that at some point we may need a virtual CALL_PPUREAD which just peeks and doesnt increment any counters
 						//this could be handy for the debugging tools also
 						bool realSprite = (s < 8);
+						bool junksprite = (s >= oamcount);
+
+						if (!reg_2001.PPUON)
+							junksprite = true;
 
 						TempOAM* oam = &oams[(scanslot << 6) + s];
 						{
@@ -369,7 +369,17 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 							//TODO - fake sprites should not come through ppubus_read but rather peek it
 							//(at least, they should not probe it with AddressPPU. maybe the difference between peek and read is not necessary)
 
-							//pattern table fetches
+							if (junksprite)
+							{
+								if (realSprite)
+								{
+									ppubus_read(patternAddress, true);
+									ppubus_read(patternAddress, true);
+									runppu(kFetchTime * 2);
+								}
+							}
+							else
+							{
 								int addr = patternAddress;
 								oam->patterns[0] = ppubus_read(addr, true);
 								if (realSprite) runppu(kFetchTime);
@@ -384,6 +394,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 									oam->patterns[0] = BITREV.byte_8[oam->patterns[0]];
 									oam->patterns[1] = BITREV.byte_8[oam->patterns[1]];
 								}
+							}
 						} //c# fixed oam
 					
 					} //sprite pattern fetch loop