diff --git a/BizHawk.Client.Common/movie/MnemonicsGenerator.cs b/BizHawk.Client.Common/movie/MnemonicsGenerator.cs
index 835e2ce1d5..2ae68342b5 100644
--- a/BizHawk.Client.Common/movie/MnemonicsGenerator.cs
+++ b/BizHawk.Client.Common/movie/MnemonicsGenerator.cs
@@ -76,7 +76,7 @@ namespace BizHawk.Client.Common
 					case "SAT":
 						return "|.|.............|.............|";
 					case "WSWAN":
-						return "|....|....|...|";
+						return "|....|....|.....|";
 				}
 			}
 		}
diff --git a/BizHawk.Client.Common/movie/MovieMnemonics.cs b/BizHawk.Client.Common/movie/MovieMnemonics.cs
index bcb24ea9ac..d0d44c77f5 100644
--- a/BizHawk.Client.Common/movie/MovieMnemonics.cs
+++ b/BizHawk.Client.Common/movie/MovieMnemonics.cs
@@ -211,6 +211,7 @@ namespace BizHawk.Client.Common
 			new Tuple<string, char>("B", 'B'),
 			new Tuple<string, char>("A", 'A'),
 			new Tuple<string, char>("Power", 'P'),
+			new Tuple<string, char>("Rotate", 'R'),
 			new Tuple<string, char>(null, '|'),
 		};
 	}
diff --git a/BizHawk.Emulation.Cores/Consoles/WonderSwan/BizSwan.cs b/BizHawk.Emulation.Cores/Consoles/WonderSwan/BizSwan.cs
index c20643ac99..e9fee26375 100644
--- a/BizHawk.Emulation.Cores/Consoles/WonderSwan/BizSwan.cs
+++ b/BizHawk.Emulation.Cores/Consoles/WonderSwan/BizSwan.cs
@@ -42,9 +42,10 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 		/// <param name="surface">uint32 video output buffer</param>
 		/// <param name="soundbuff">int16 sound output buffer</param>
 		/// <param name="soundbuffsize">[In] max hold size of soundbuff [Out] number of samples actually deposited</param>
+		/// <param name="IsRotated">(out) true if the screen is rotated left 90</param>
 		/// <returns>true if lagged</returns>
 		[DllImport(dd, CallingConvention = cc)]
-		public static extern bool bizswan_advance(IntPtr core, Buttons buttons, bool novideo, int[] surface, short[] soundbuff, ref int soundbuffsize);
+		public static extern bool bizswan_advance(IntPtr core, Buttons buttons, bool novideo, int[] surface, short[] soundbuff, ref int soundbuffsize, ref bool IsRotated);
 
 		/// <summary>
 		/// load rom
@@ -170,6 +171,7 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 			Start = 0x0100,
 			A = 0x0200,
 			B = 0x0400,
+			Rotate = 0x8000,
 		}
 
 		public enum Language : uint
diff --git a/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs b/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
index bee8490f59..00267f278f 100644
--- a/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
+++ b/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
@@ -19,7 +19,7 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 		public static readonly ControllerDefinition WonderSwanController = new ControllerDefinition
 		{
 			Name = "WonderSwan Controller",
-			BoolButtons = { "Up X", "Down X", "Left X", "Right X", "Up Y", "Down Y", "Left Y", "Right Y", "Start", "B", "A", "Power" }
+			BoolButtons = { "Up X", "Down X", "Left X", "Right X", "Up Y", "Down Y", "Left Y", "Right Y", "Start", "B", "A", "Power", "Rotate" }
 		};
 		public ControllerDefinition ControllerDefinition { get { return WonderSwanController; } }
 		public IController Controller { get; set; }
@@ -38,6 +38,7 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 			if (Controller["Start"]) ret |= BizSwan.Buttons.Start;
 			if (Controller["B"]) ret |= BizSwan.Buttons.B;
 			if (Controller["A"]) ret |= BizSwan.Buttons.A;
+			if (Controller["Rotate"]) ret |= BizSwan.Buttons.Rotate;
 			return ret;
 		}
 
@@ -103,11 +104,13 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 			if (Controller["Power"])
 				BizSwan.bizswan_reset(Core);
 
+			bool rotate = false;
 			int soundbuffsize = sbuff.Length;
-			IsLagFrame = BizSwan.bizswan_advance(Core, GetButtons(), !render, vbuff, sbuff, ref soundbuffsize);
+			IsLagFrame = BizSwan.bizswan_advance(Core, GetButtons(), !render, vbuff, sbuff, ref soundbuffsize, ref rotate);
 			if (soundbuffsize == sbuff.Length)
 				throw new Exception();
 			sbuffcontains = soundbuffsize;
+			InitVideo(rotate);
 
 			if (IsLagFrame)
 				LagCount++;
diff --git a/output/dll/bizswan.dll b/output/dll/bizswan.dll
index a45545bccc..dcbd9d7842 100644
Binary files a/output/dll/bizswan.dll and b/output/dll/bizswan.dll differ
diff --git a/wonderswan/system.cpp b/wonderswan/system.cpp
index e87d24b854..c88e99c51c 100644
--- a/wonderswan/system.cpp
+++ b/wonderswan/system.cpp
@@ -80,6 +80,10 @@ namespace MDFN_IEN_WSWAN
 
 	bool System::Advance(uint16 buttons, bool novideo, uint32 *surface, int16 *soundbuff, int &soundbuffsize)
 	{
+		// we hijack the top bit of the buttons input and use it as a positive edge sensitive toggle to the rotate input
+		rotate ^= (buttons & 0x8000) > (oldbuttons & 0x8000);
+		oldbuttons = buttons;
+
 		memory.WSButtonStatus = rotate ? RotateButtons(buttons) : buttons;
 		memory.Lagged = true;
 		while (!gfx.ExecuteLine(surface, novideo))
@@ -306,6 +310,7 @@ namespace MDFN_IEN_WSWAN
 		SSS(interrupt);
 	
 		NSS(rotate);
+		NSS(oldbuttons);
 	}
 
 	void System::SaveRamClearHacky(const SyncSettings &s)
@@ -330,9 +335,11 @@ namespace MDFN_IEN_WSWAN
 		s->Reset();
 	}
 
-	EXPORT int bizswan_advance(System *s, uint16 buttons, bool novideo, uint32 *surface, int16 *soundbuff, int *soundbuffsize)
+	EXPORT int bizswan_advance(System *s, uint16 buttons, bool novideo, uint32 *surface, int16 *soundbuff, int *soundbuffsize, int *IsRotated)
 	{
-		return s->Advance(buttons, novideo, surface, soundbuff, *soundbuffsize);
+		int ret = s->Advance(buttons, novideo, surface, soundbuff, *soundbuffsize);
+		*IsRotated = s->rotate;
+		return ret;
 	}
 
 	EXPORT int bizswan_load(System *s, const uint8 *data, int length, const SyncSettings *settings, int *IsRotated)
diff --git a/wonderswan/system.h b/wonderswan/system.h
index 875d926f53..fb92d91bfe 100644
--- a/wonderswan/system.h
+++ b/wonderswan/system.h
@@ -57,6 +57,7 @@ public:
 	Interrupt interrupt;
 	
 	bool rotate; // rotate screen and controls left 90
+	uint16 oldbuttons;
 
 	template<bool isReader>void SyncState(NewState *ns);
 };