diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.cs
index e6739e5f16..7de0858b80 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.cs
@@ -166,7 +166,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 				case ControlType.None:
 					return LibGPGX.INPUT_SYSTEM.SYSTEM_NONE;
 				case ControlType.Normal:
-					return LibGPGX.INPUT_SYSTEM.SYSTEM_MD_GAMEPAD;
+					return LibGPGX.INPUT_SYSTEM.SYSTEM_GAMEPAD;
 				case ControlType.Xea1p:
 					return LibGPGX.INPUT_SYSTEM.SYSTEM_XE_A1P;
 				case ControlType.Activator:
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGXControlConverter.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGXControlConverter.cs
index db32f515d9..f439a20d38 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGXControlConverter.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGXControlConverter.cs
@@ -242,7 +242,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 					case LibGPGX.INPUT_DEVICE.DEVICE_PADDLE:
 					case LibGPGX.INPUT_DEVICE.DEVICE_SPORTSPAD:
 					case LibGPGX.INPUT_DEVICE.DEVICE_TEREBI:
-						throw new Exception("Not implemented yet.");
+						throw new NotImplementedException();
 					case LibGPGX.INPUT_DEVICE.DEVICE_ACTIVATOR:
 						AddToController(i, player, Activator);
 						player++;
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs
index f6780b9b57..0dd9a00fc6 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs
@@ -126,19 +126,20 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 
 		public enum INPUT_SYSTEM : byte
 		{
-			SYSTEM_NONE = 0,        // unconnected port	
-			SYSTEM_MD_GAMEPAD = 1,  // single 3-buttons or 6-buttons Control Pad 	
-			SYSTEM_MOUSE = 2,       // Sega Mouse 	
-			SYSTEM_MENACER = 3,     // Sega Menacer -- port B only
-			SYSTEM_JUSTIFIER = 4,   // Konami Justifiers -- port B only
-			SYSTEM_XE_A1P = 5,      // XE-A1P analog controller -- port A only
-			SYSTEM_ACTIVATOR = 6,   // Sega Activator 	
-			SYSTEM_MS_GAMEPAD = 7,  // single 2-buttons Control Pad -- Master System
-			SYSTEM_LIGHTPHASER = 8, // Sega Light Phaser -- Master System
-			SYSTEM_PADDLE = 9,      // Sega Paddle Control -- Master System
-			SYSTEM_SPORTSPAD = 10,  // Sega Sports Pad -- Master System
-			SYSTEM_TEAMPLAYER = 11, // Multi Tap -- Sega TeamPlayer 	
-			SYSTEM_WAYPLAY = 12,    // Multi Tap -- EA 4-Way Play -- use both ports
+			SYSTEM_NONE = 0,          // unconnected port
+			SYSTEM_GAMEPAD = 1,	      // single 2-buttons, 3-buttons or 6-buttons Control Pad
+			SYSTEM_MOUSE = 2,         // Sega Mouse
+			SYSTEM_MENACER = 3,       // Sega Menacer -- port B only
+			SYSTEM_JUSTIFIER = 4,     // Konami Justifiers -- port B only
+			SYSTEM_XE_A1P = 5,        // XE-A1P analog controller -- port A only
+			SYSTEM_ACTIVATOR = 6,     // Sega Activator
+			SYSTEM_LIGHTPHASER = 7,   // Sega Light Phaser -- Master System
+			SYSTEM_PADDLE = 8,        // Sega Paddle Control -- Master System
+			SYSTEM_SPORTSPAD = 9,     // Sega Sports Pad -- Master System
+			SYSTEM_GRAPHIC_BOARD = 10,// Sega Graphic Board
+			SYSTEM_MASTERTAP = 11,    // Multi Tap -- Furrtek's Master Tap (unofficial)
+			SYSTEM_TEAMPLAYER = 12,   // Multi Tap -- Sega TeamPlayer
+			SYSTEM_WAYPLAY = 13,      // Multi Tap -- EA 4-Way Play -- use both ports
 		}
 
 		public enum INPUT_DEVICE : byte