diff --git a/src/emu/cpu/mb86233/mb86233.c b/src/emu/cpu/mb86233/mb86233.c
index 8962f93f4bb..c2cc7e1a2c3 100644
--- a/src/emu/cpu/mb86233/mb86233.c
+++ b/src/emu/cpu/mb86233/mb86233.c
@@ -908,7 +908,7 @@ UINT32 mb86233_cpu_device::INDIRECT( UINT32 reg, int source )
 	}
 	else if ( mode == 2 )
 	{
-		UINT32  addr = reg & 0x1f;
+		UINT32  addr = reg & 0x3f;
 
 		if ( source )
 		{
@@ -960,6 +960,13 @@ UINT32 mb86233_cpu_device::INDIRECT( UINT32 reg, int source )
 			else
 				GETGPR(3) += ( reg & 0x1f );
 		}
+		if( mode == 7)
+		{
+			if ( source )
+				GETGPR(2)&=0x3f;
+			else
+				GETGPR(3)&=0x3f;
+		}
 
 		return addr;
 	}
@@ -985,6 +992,8 @@ void mb86233_cpu_device::execute_run()
 		debugger_instruction_hook(this, GETPC());
 
 		opcode = ROPCODE(GETPC());
+		//if(GETPC() != 0x77)
+		//printf("%08x %08x\n",GETPC(),opcode);
 
 		GETFIFOWAIT() = 0;
 
diff --git a/src/mame/drivers/model2.c b/src/mame/drivers/model2.c
index 6d7b53c9404..035ab2f1e37 100644
--- a/src/mame/drivers/model2.c
+++ b/src/mame/drivers/model2.c
@@ -1959,6 +1959,64 @@ static INPUT_PORTS_START( daytona )
 	PORT_BIT( 0xff, 0x00, IPT_PEDAL2 ) PORT_SENSITIVITY(30) PORT_KEYDELTA(10) PORT_PLAYER(1)
 INPUT_PORTS_END
 
+static INPUT_PORTS_START( manxtt )
+	PORT_START("1c00000")
+	PORT_BIT( 0x0000ffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+	PORT_BIT( 0xffff0000, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, model2_state,_1c00000_r, NULL)
+
+	PORT_START("1c00004")
+	PORT_BIT( 0x0000ffff, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, driver_device,custom_port_read, "IN2")
+	PORT_BIT( 0xffff0000, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, driver_device,custom_port_read, "IN3")
+
+	PORT_START("1c0000c")
+	PORT_BIT( 0xffffffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("1c00010")
+	PORT_BIT( 0x0000ffff, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, driver_device,custom_port_read, "IN0")
+	PORT_BIT( 0xffff0000, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, driver_device,custom_port_read, "IN1")
+
+	PORT_START("1c00014")
+	PORT_BIT( 0x0000ffff, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, driver_device,custom_port_read, "IN4")
+	PORT_BIT( 0xffff0000, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("1c0001c")
+	PORT_BIT( 0x0000001a, IP_ACTIVE_HIGH, IPT_SPECIAL ) // these must be high
+	PORT_BIT( 0x0000ffe5, IP_ACTIVE_LOW, IPT_UNKNOWN )
+	PORT_BIT( 0xffff0000, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, model2_state,_1c0001c_r, NULL)
+
+	PORT_START("IN0")
+	PORT_BIT(0x0001, IP_ACTIVE_LOW, IPT_COIN1 )
+	PORT_BIT(0x0002, IP_ACTIVE_LOW, IPT_COIN2 )
+	PORT_SERVICE_NO_TOGGLE( 0x0004, IP_ACTIVE_LOW )
+	PORT_BIT(0x0008, IP_ACTIVE_LOW, IPT_SERVICE1 )
+	PORT_BIT(0x0020, IP_ACTIVE_LOW, IPT_BUTTON3 ) PORT_PLAYER(1) PORT_NAME("VR") // VR
+	PORT_BIT(0x0040, IP_ACTIVE_LOW, IPT_START1 ) PORT_NAME("P1 Start / VR")
+	PORT_BIT(0x0090, IP_ACTIVE_LOW, IPT_UNUSED )
+	PORT_BIT(0xff00, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("IN1")
+	PORT_BIT(0xffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("IN2")
+	PORT_BIT(0x00ff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+	PORT_BIT(0xff00, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("IN3")
+	PORT_BIT(0xffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("IN4")
+	PORT_BIT(0xffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
+
+	PORT_START("ANA0")  // throttle
+	PORT_BIT( 0xff, 0x00, IPT_PEDAL ) PORT_SENSITIVITY(30) PORT_KEYDELTA(10) PORT_PLAYER(1)
+
+	PORT_START("ANA1")  // brake
+	PORT_BIT( 0xff, 0x00, IPT_PEDAL2 ) PORT_SENSITIVITY(30) PORT_KEYDELTA(10) PORT_PLAYER(1)
+
+	PORT_START("ANA2")  // bank
+	PORT_BIT( 0xff, 0x80, IPT_PADDLE ) PORT_SENSITIVITY(30) PORT_KEYDELTA(10) PORT_PLAYER(1) PORT_REVERSE
+INPUT_PORTS_END
+
 static INPUT_PORTS_START( srallyc )
 	PORT_START("1c00000")
 	PORT_BIT( 0x0000ffff, IP_ACTIVE_LOW, IPT_UNKNOWN )
@@ -5867,7 +5925,7 @@ DRIVER_INIT_MEMBER(model2_state,sgt24h)
 	m_protstate = m_protpos = 0;
 
 	ROM[0x56578/4] = 0x08000004;
-	ROM[0x5b3e8/4] = 0x08000004;
+	//ROM[0x5b3e8/4] = 0x08000004;
 }
 
 DRIVER_INIT_MEMBER(model2_state,overrev)
@@ -5911,8 +5969,8 @@ GAME( 1994, vcop,            0, model2o, vcop,    driver_device, 0,       ROT0,
 GAME( 1994, vcopa,           0, model2o, vcop,    driver_device, 0,       ROT0, "Sega",   "Virtua Cop (Revision A)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
 
 // Model 2A-CRX (TGPs, SCSP sound board)
-GAME( 1995, manxtt,          0, manxttdx,model2, driver_device, 0, ROT0, "Sega", "Manx TT Superbike - DX (Revision D)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
-GAME( 1995, manxttc,         0, model2a, model2,  driver_device, 0,       ROT0, "Sega",   "Manx TT Superbike - Twin (Revision C)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
+GAME( 1995, manxtt,          0, manxttdx,manxtt,  driver_device, 0, ROT0, "Sega", "Manx TT Superbike - DX (Revision D)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
+GAME( 1995, manxttc,         0, model2a, manxtt,  driver_device, 0,       ROT0, "Sega",   "Manx TT Superbike - Twin (Revision C)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
 GAME( 1995, srallyc,         0, srallyc, srallyc, model2_state,  srallyc, ROT0, "Sega",   "Sega Rally Championship - TWIN (Revision C)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
 GAME( 1995, srallycb,  srallyc, srallyc, srallyc, model2_state,  srallyc, ROT0, "Sega",   "Sega Rally Championship - TWIN (Revision B)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )
 GAME( 1995, srallyca,  srallyc, srallyc, srallyc, model2_state,  srallyc, ROT0, "Sega",   "Sega Rally Championship - DX (Revision A)", GAME_NOT_WORKING|GAME_IMPERFECT_GRAPHICS )