diff --git a/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/HW_Registers.cs b/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/HW_Registers.cs
index 8371173f91..26f57ba2f0 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/HW_Registers.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/HW_Registers.cs
@@ -58,7 +58,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 						ret = (byte)((portB_ret & 0x7F) | (PB7 ? 0x80 : 0x0));
 					}
 
-					if (!dir_ctrl.Bit(5)) { ret |= (byte)(!compare ? 0x0 : 0x20); }
+					if (!dir_ctrl.Bit(5)) { ret |= (byte)(compare ? 0x20 : 0x0); }
 
 					int_fl &= 0xE7;
 					update_int_fl();
@@ -216,26 +216,26 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 					{
 						if (sel1)
 						{
-							if (portA_ret >= joy2_UD) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy2_UD) { compare = false; }
+							else { compare = true; }
 						}
 						else
 						{							
-							if (portA_ret >= joy1_UD) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy1_UD) { compare = false; }
+							else { compare = true; }
 						}
 					}
 					else
 					{
 						if (sel1)
 						{
-							if (portA_ret >= joy2_LR) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy2_LR) { compare = false; }
+							else { compare = true; }
 						}
 						else
 						{
-							if (portA_ret >= joy1_LR) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy1_LR) { compare = false; }
+							else { compare = true; }
 						}
 					}
 
@@ -295,26 +295,26 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 					{
 						if (sel1)
 						{
-							if (portA_ret >= joy2_UD) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy2_UD) { compare = false; }
+							else { compare = true; }
 						}
 						else
-						{								
-							if (portA_ret >= joy1_UD) { compare = true; }
-							else { compare = false; }
+						{
+							if ((byte)(portA_ret ^ 0x80) >= joy1_UD) { compare = false; }
+							else { compare = true; }
 						}
 					}
 					else
 					{
 						if (sel1)
 						{
-							if (portA_ret >= joy2_LR) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy2_LR) { compare = false; }
+							else { compare = true; }
 						}
 						else
 						{
-							if (portA_ret >= joy1_LR) { compare = true; }
-							else { compare = false; }
+							if ((byte)(portA_ret ^ 0x80) >= joy1_LR) { compare = false; }
+							else { compare = true; }
 						}
 					}
 
@@ -459,6 +459,33 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 						ppu.new_draw_line();
 					}
 
+					if (sel0)
+					{
+						if (sel1)
+						{
+							if ((byte)(portA_ret ^ 0x80) >= joy2_UD) { compare = false; }
+							else { compare = true; }
+						}
+						else
+						{
+							if ((byte)(portA_ret ^ 0x80) >= joy1_UD) { compare = false; }
+							else { compare = true; }
+						}
+					}
+					else
+					{
+						if (sel1)
+						{
+							if ((byte)(portA_ret ^ 0x80) >= joy2_LR) { compare = false; }
+							else { compare = true; }
+						}
+						else
+						{
+							if ((byte)(portA_ret ^ 0x80) >= joy1_LR) { compare = false; }
+							else { compare = true; }
+						}
+					}
+
 					int_fl &= 0xFC;
 					update_int_fl();
 					break;
diff --git a/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/VectrexHawk.IEmulator.cs b/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/VectrexHawk.IEmulator.cs
index 438b88e167..eb709dd2f2 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/VectrexHawk.IEmulator.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/VectrexHawk.IEmulator.cs
@@ -42,10 +42,10 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 			if (ControllerDefinition.Name == "Vectrex Analog Controller")
 			{
 				// joystick position is based on pot reading
-				joy1_LR = (byte)(255 - (controller.AxisValue("P1 Stick X") + 128));
-				joy1_UD = (byte)(controller.AxisValue("P1 Stick Y") + 128);
-				joy2_LR = (byte)(255 - (controller.AxisValue("P2 Stick X") + 128));
-				joy2_UD = (byte)(controller.AxisValue("P2 Stick Y") + 128);
+				joy1_LR = (byte)(controller.AxisValue("P1 Stick X") + 128);
+				joy1_UD = (byte)(-(controller.AxisValue("P1 Stick Y") + 1) + 128);
+				joy2_LR = (byte)(controller.AxisValue("P2 Stick X") + 128);
+				joy2_UD = (byte)(-(controller.AxisValue("P2 Stick Y") + 1) + 128);
 			}
 			else
 			{
@@ -54,15 +54,15 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 				// so convention will be up and right dominate
 				joy1_UD = joy1_LR = joy2_UD = joy2_LR = 128;
 
-				if (controller.IsPressed("P1 Down")) { joy1_UD = 0xFF; }
-				if (controller.IsPressed("P1 Up")) { joy1_UD = 0; }
-				if (controller.IsPressed("P1 Left")) { joy1_LR = 0xFF; }
-				if (controller.IsPressed("P1 Right")) { joy1_LR = 0; }
+				if (controller.IsPressed("P1 Down")) { joy1_UD = 0; }
+				if (controller.IsPressed("P1 Up")) { joy1_UD = 0xFF; }
+				if (controller.IsPressed("P1 Left")) { joy1_LR = 0; }
+				if (controller.IsPressed("P1 Right")) { joy1_LR = 0xFF; }
 
-				if (controller.IsPressed("P2 Down")) { joy2_UD = 0xFF; }
-				if (controller.IsPressed("P2 Up")) { joy2_UD = 0; }
-				if (controller.IsPressed("P2 Left")) { joy2_LR = 0xFF; }
-				if (controller.IsPressed("P2 Right")) { joy2_LR = 0; }
+				if (controller.IsPressed("P2 Down")) { joy2_UD = 0; }
+				if (controller.IsPressed("P2 Up")) { joy2_UD = 0xFF; }
+				if (controller.IsPressed("P2 Left")) { joy2_LR = 0; }
+				if (controller.IsPressed("P2 Right")) { joy2_LR = 0xFF; }
 			}
 
 			frame_end = false;