diff --git a/ChangeLog b/ChangeLog
index b995dfc..1310378 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -11,6 +11,7 @@ Core:
  Additions:
   - Homebrew module (Phil Smith)
   - Support for mapper 31 (rainwarrior)
+  - Support for MMC3 Big CHR-RAM Board
 
 ----------------------------------------------------------------
 1.49
diff --git a/source/core/NstCartridge.cpp b/source/core/NstCartridge.cpp
index c159d97..3dca9a0 100644
--- a/source/core/NstCartridge.cpp
+++ b/source/core/NstCartridge.cpp
@@ -276,7 +276,7 @@ namespace Nes
 
 			if (profile.board.type.empty() || !b.DetectBoard( profile.board.type.c_str(), profile.board.GetWram() ))
 			{
-				if (profile.board.mapper == Profile::Board::NO_MAPPER || (!b.DetectBoard( profile.board.mapper, profile.board.GetWram(), profileEx.wramAuto, profile.board.subMapper ) && board))
+				if (profile.board.mapper == Profile::Board::NO_MAPPER || (!b.DetectBoard( profile.board.mapper, profile.board.subMapper, profile.board.chrRam, profile.board.GetWram(), profileEx.wramAuto ) && board))
 					return RESULT_ERR_UNSUPPORTED_MAPPER;
 
 				if (profile.board.type.empty())
diff --git a/source/core/NstCartridgeInes.cpp b/source/core/NstCartridgeInes.cpp
index 7be67fe..37e6789 100644
--- a/source/core/NstCartridgeInes.cpp
+++ b/source/core/NstCartridgeInes.cpp
@@ -233,6 +233,7 @@ namespace Nes
 				{
 					if (setup.chrRam)
 					{
+						profile.board.chrRam = setup.chrRam / SIZE_1K;
 						log << title
 							<< (setup.chrRam % SIZE_1K ? setup.chrRam : setup.chrRam / SIZE_1K)
 							<< (setup.chrRam % SIZE_1K ? " bytes" : "k")
diff --git a/source/core/api/NstApiCartridge.hpp b/source/core/api/NstApiCartridge.hpp
index 49ae5a6..9ae71f5 100644
--- a/source/core/api/NstApiCartridge.hpp
+++ b/source/core/api/NstApiCartridge.hpp
@@ -810,6 +810,11 @@ namespace Nes
 					* Submapper ID.
 					*/
 					uint subMapper;
+
+					/**
+					* CHR RAM Size.
+					*/
+					uint chrRam;
 				};
 
 				/**
diff --git a/source/core/board/NstBoard.cpp b/source/core/board/NstBoard.cpp
index dab4931..86d30c4 100644
--- a/source/core/board/NstBoard.cpp
+++ b/source/core/board/NstBoard.cpp
@@ -1218,7 +1218,7 @@ namespace Nes
 				return true;
 			}
 
-			bool Board::Context::DetectBoard(const byte mapper,const dword wram,bool wramAuto,const byte submapper)
+			bool Board::Context::DetectBoard(const byte mapper,const byte submapper,const dword chrRam,const dword wram,bool wramAuto)
 			{
 				Type::Id id;
 
@@ -1446,6 +1446,13 @@ namespace Nes
 							break;
 						}
 
+						if (chrRam == 32)
+						{
+							name = "UNL-MMC3BIGCHRRAM";
+							id = Type::UNL_MMC3BIGCHRRAM;
+							break;
+						}
+
 						if (nmt == Type::NMT_FOURSCREEN)
 						{
 							if (prg == SIZE_64K && (chr == SIZE_32K || chr == SIZE_64K) && !wram && !useWramAuto)
@@ -3403,6 +3410,7 @@ namespace Nes
 					case Type::STD_TR1ROM                 :
 					case Type::STD_TSROM                  :
 					case Type::STD_TVROM                  :
+					case Type::UNL_MMC3BIGCHRRAM          :
 					case Type::UNL_TRXROM                 : return new TxRom  (c);
 					case Type::STD_TLSROM                 : return new TlsRom (c);
 					case Type::STD_TKSROM                 : return new TksRom (c);
diff --git a/source/core/board/NstBoard.hpp b/source/core/board/NstBoard.hpp
index f5780e8..2e7ffea 100644
--- a/source/core/board/NstBoard.hpp
+++ b/source/core/board/NstBoard.hpp
@@ -557,6 +557,7 @@ namespace Nes
 						UNL_UXROM_M5               = MakeId<  180, 4096,    8,  8,  0, CRM_0,  NMT_X,  0 >::ID,
 						UNL_TRXROM                 = MakeId<    4,  512,  256,  8,  0, CRM_0,  NMT_4,  0 >::ID,
 						UNL_XZY                    = MakeId<  176, 1024,  256,  8,  0, CRM_0,  NMT_X,  0 >::ID,
+						UNL_MMC3BIGCHRRAM          = MakeId<    4,  512,    0,  0,  0, CRM_32, NMT_X,  0 >::ID,
 						// Waixing
 						WAIXING_PS2_0              = MakeId<   15, 1024,    0,  0,  0, CRM_8,  NMT_V,  0 >::ID,
 						WAIXING_PS2_1              = MakeId<   15, 1024,    0,  8,  0, CRM_8,  NMT_V,  0 >::ID,
@@ -652,7 +653,7 @@ namespace Nes
 					Context(Cpu*,Apu*,Ppu*,Ram&,Ram&,const Ram&,Type::Nmt,bool,bool,Chips&);
 
 					bool DetectBoard(wcstring,dword);
-					bool DetectBoard(byte,dword,bool,byte);
+					bool DetectBoard(byte,byte,dword,dword,bool);
 
 					cstring name;
 					Type type;