Start Mapper 197 (based on MMC3) and sort out the use of this vs Mapper 91.

BizHawk.Emulation/BizHawk.Emulation.csproj

@@ -200,6 +200,7 @@
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper191.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper192.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper194.cs" />
+    <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper197.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper205.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\Mapper245.cs" />
     <Compile Include="Consoles\Nintendo\NES\Boards\MMC3_family\MMC3.cs" />

BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper091.cs

@@ -8,70 +8,8 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 	class Mapper91 : NES.NESBoardBase
 	{
 		/*
-		*  Here are Disch's original notes:  
+		*Note: Street Fighter III (Unl) is actually mapper 197.  However variations such as Street Fighter III (9 Fighter) and Mari Street Fighter III use this mapper
-		========================
+		//http://wiki.nesdev.com/w/index.php/INES_Mapper_091
-		=  Mapper 091          =
-		========================
- 
- 
-		Example Game:
-		--------------------------
-		Street Fighter 3
- 
- 
-		Notes:
-		---------------------------
-		Regs exist at $6000-7FFF, so this mapper has no SRAM.
- 
- 
-		Registers:
-		---------------------------
- 
-		Range,Mask:   $6000-7FFF, $7003
- 
-		$6000-6003:  CHR Regs
-		$7000-7001:  [.... PPPP]  PRG Regs
- 
-		$7002 [.... ....]  IRQ Stop
-		$7003 [.... ....]  IRQ Start
- 
- 
- 
-		CHR Setup:
-		---------------------------
- 
-		  $0000   $0400   $0800   $0C00   $1000   $1400   $1800   $1C00 
-		+---------------+---------------+---------------+---------------+
-		|     $6000     |     $6001     |     $6002     |     $6003     |
-		+---------------+---------------+---------------+---------------+
- 
-		PRG Setup:
-		---------------------------
- 
-		  $8000   $A000   $C000   $E000  
-		+-------+-------+-------+-------+
-		| $7000 | $7001 | { -2} | { -1} |
-		+-------+-------+-------+-------+
- 
- 
-		IRQs:
-		---------------------------
- 
-		IRQs on this mapper seem to behave exactly like MMC3 -- except it's fixed so that it will only fire after 8
-		scanlines.  This is easily emulatable by using MMC3 logic.
- 
-		Write to $7002/$7003 can translate directly to write(s) to the following MMC3 registers:
- 
-		on $7002 write:
-		a) write to $E000
- 
-		on $7003 write:
-		a) write $07 to $C000
-		b) write to $C001
-		c) write to $E001
- 
- 
-		For details on MMC3 IRQ operation, see mapper 004
 		*/
 
 		ByteBuffer chr_regs_2k = new ByteBuffer(4);
@@ -84,7 +22,6 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 			switch (Cart.board_type)
 			{
 				case "MAPPER091":
-				case "MAPPER197": //GoodNES reports 197 instead of 91
 					break;
 				default:
 					return false;
@@ -164,7 +101,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
 		{
 			if (addr < 0x2000)
 			{
-				int bank_2k = (addr >> 11);
+				int bank_2k = (addr >> 11) - 1;
 				bank_2k = chr_regs_2k[bank_2k];
 				bank_2k &= chr_bank_mask_2k;
 				return VROM[(bank_2k * 0x800) + addr];

BizHawk.MultiClient/output/gamedb.txt

@@ -114,7 +114,6 @@ sha1:6DF9AECF5787C0833B0F05A9A83D0E58A6153977		Rumblestation 15-in-1 (Unl)	NES
 sha1:E4BFD5AB3C3649DBD36B9A7280CF431641BCBCEC		Peek-A-Boo Poker (Unl)	NES		board=NES-CNROM;PRG=32;CHR=24;WRAM=0
 sha1:39294394A0631708F58397371CE14075AE1FB7E6		Peek-A-Boo Poker (Panesian)	NES		board=NES-CNROM;PRG=32;CHR=64;WRAM=0
 sha1:C87E7E6A68DD9C7E24652CD2C7D390A14E8ADF04		Lagrange Point	NES		board=KONAMI-VRC-7;PRG=512;CHR=0;WRAM=8;PRAM=8;PCB=352402
-sha1:E05B0FCA7EA2F6433FA06DD204F7265417B91BBE		Street Fighter III	NES		board=MAPPER091;PRG=128;CHR=512
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