diff --git a/.gitattributes b/.gitattributes
index a94eab432ae..7ac57617c6c 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1017,6 +1017,8 @@ src/emu/bus/msx_cart/rtype.c svneol=native#text/plain
 src/emu/bus/msx_cart/rtype.h svneol=native#text/plain
 src/emu/bus/msx_cart/superloderunner.c svneol=native#text/plain
 src/emu/bus/msx_cart/superloderunner.h svneol=native#text/plain
+src/emu/bus/msx_cart/yamaha.c svneol=native#text/plain
+src/emu/bus/msx_cart/yamaha.h svneol=native#text/plain
 src/emu/bus/msx_slot/bunsetsu.c svneol=native#text/plain
 src/emu/bus/msx_slot/bunsetsu.h svneol=native#text/plain
 src/emu/bus/msx_slot/cartridge.c svneol=native#text/plain
diff --git a/src/emu/bus/bus.mak b/src/emu/bus/bus.mak
index 8c3140d1a7f..e736f1c7a0e 100644
--- a/src/emu/bus/bus.mak
+++ b/src/emu/bus/bus.mak
@@ -420,6 +420,7 @@ BUSOBJS += $(BUSOBJ)/msx_cart/msxdos2.o
 BUSOBJS += $(BUSOBJ)/msx_cart/nomapper.o
 BUSOBJS += $(BUSOBJ)/msx_cart/rtype.o
 BUSOBJS += $(BUSOBJ)/msx_cart/superloderunner.o
+BUSOBJS += $(BUSOBJ)/msx_cart/yamaha.o
 endif
 
 
diff --git a/src/emu/bus/msx_cart/cartridge.c b/src/emu/bus/msx_cart/cartridge.c
index 905fb25d136..3111e72275e 100644
--- a/src/emu/bus/msx_cart/cartridge.c
+++ b/src/emu/bus/msx_cart/cartridge.c
@@ -12,6 +12,7 @@
 #include "nomapper.h"
 #include "rtype.h"
 #include "superloderunner.h"
+#include "yamaha.h"
 
 
 SLOT_INTERFACE_START(msx_cart)
@@ -44,6 +45,7 @@ SLOT_INTERFACE_END
 
 msx_cart_interface::msx_cart_interface(const machine_config &mconfig, device_t &device)
 	: device_slot_card_interface(mconfig, device)
+	, m_out_irq_cb(*this)
 {
 }
 
@@ -61,3 +63,12 @@ void msx_cart_interface::sram_alloc(UINT32 size)
 {
 	m_sram.resize(size);
 }
+
+
+// Several yamaha machines had 60 pin expansion slots. The pinouts of these slots was
+// exactly the same as the regular 50 pin cartridge slots. The lowest 10 pins are simply
+// not connected.
+SLOT_INTERFACE_START(msx_yamaha_60pin)
+	SLOT_INTERFACE("sfg01", MSX_CART_SFG01)
+SLOT_INTERFACE_END
+
diff --git a/src/emu/bus/msx_cart/cartridge.h b/src/emu/bus/msx_cart/cartridge.h
index bcd51c263a7..7df0dc662a4 100644
--- a/src/emu/bus/msx_cart/cartridge.h
+++ b/src/emu/bus/msx_cart/cartridge.h
@@ -3,6 +3,7 @@
 
 
 SLOT_INTERFACE_EXTERN(msx_cart);
+SLOT_INTERFACE_EXTERN(msx_yamaha_60pin);   // 60 pin expansion slots as found in yamaha machines
 
 
 class msx_cart_interface : public device_slot_card_interface
@@ -10,6 +11,8 @@ class msx_cart_interface : public device_slot_card_interface
 public:
 	msx_cart_interface(const machine_config &mconfig, device_t &device);
 
+	template<class _Object> void set_out_irq_cb(_Object object) { m_out_irq_cb.set_callback(object); m_out_irq_cb.resolve_safe(); }
+
 	// This is called after loading cartridge contents and allows the cartridge
 	// implementation to perform some additional initialization based on the
 	// cartridge contents.
@@ -36,6 +39,7 @@ protected:
 	dynamic_buffer m_rom;
 	dynamic_buffer m_ram;
 	dynamic_buffer m_sram;
+	devcb_write_line m_out_irq_cb;
 };
 
 
diff --git a/src/emu/bus/msx_cart/msx_audio.c b/src/emu/bus/msx_cart/msx_audio.c
index 0d108be875f..c6fc781feb6 100644
--- a/src/emu/bus/msx_cart/msx_audio.c
+++ b/src/emu/bus/msx_cart/msx_audio.c
@@ -136,11 +136,13 @@ msx_cart_msx_audio_nms1205::msx_cart_msx_audio_nms1205(const machine_config &mco
 
 static MACHINE_CONFIG_FRAGMENT( msx_audio_nms1205 )
 	// This is actually incorrect. The sound output is passed back into the MSX machine where it is mixed internally and output through the system 'speaker'.
+	// At the same time the sound is also output on two output on the nms1205 cartridge itself
 	MCFG_SPEAKER_STANDARD_MONO("mono")
 	MCFG_SOUND_ADD("y8950", Y8950, XTAL_3_579545MHz)
 	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.40)
 	MCFG_Y8950_KEYBOARD_WRITE_HANDLER(DEVWRITE8("kbdc", msx_audio_kbdc_port_device, write))
 	MCFG_Y8950_KEYBOARD_READ_HANDLER(DEVREAD8("kbdc", msx_audio_kbdc_port_device, read))
+	MCFG_Y8950_IRQ_HANDLER(WRITELINE(msx_cart_msx_audio_nms1205, irq_write))
 
 	MCFG_MSX_AUDIO_KBDC_PORT_ADD("kbdc", msx_audio_keyboards, NULL)
 
@@ -174,6 +176,16 @@ const rom_entry *msx_cart_msx_audio_nms1205::device_rom_region() const
 }
 
 
+WRITE_LINE_MEMBER(msx_cart_msx_audio_nms1205::irq_write)
+{
+	// Trigger IRQ on the maincpu
+	// The 8950 seems to trigger an irq on reset, this causes an infinite loop of continuously triggering
+    // the MSX's interrupt handler. The 8950 irq will never be cleared the nms1205's irq handler hook hasn't
+	// been installed yet.
+//	m_out_irq_cb(state);
+}
+
+
 WRITE_LINE_MEMBER(msx_cart_msx_audio_nms1205::midi_in)
 {
 	// MIDI in signals is sent to both the 6850 and the MIDI thru output port
diff --git a/src/emu/bus/msx_cart/msx_audio.h b/src/emu/bus/msx_cart/msx_audio.h
index e7552ad30c2..9d5711c1145 100644
--- a/src/emu/bus/msx_cart/msx_audio.h
+++ b/src/emu/bus/msx_cart/msx_audio.h
@@ -47,6 +47,7 @@ public:
 	virtual DECLARE_READ8_MEMBER(read_cart);
 
 	DECLARE_WRITE_LINE_MEMBER(midi_in);
+	DECLARE_WRITE_LINE_MEMBER(irq_write);
 
 private:
 	required_device<y8950_device> m_y8950;
diff --git a/src/emu/bus/msx_cart/yamaha.c b/src/emu/bus/msx_cart/yamaha.c
new file mode 100644
index 00000000000..4b5c7ef4230
--- /dev/null
+++ b/src/emu/bus/msx_cart/yamaha.c
@@ -0,0 +1,143 @@
+#include "emu.h"
+#include "yamaha.h"
+
+
+const device_type MSX_CART_SFG01 = &device_creator<msx_cart_sfg01>;
+
+
+msx_cart_sfg01::msx_cart_sfg01(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+	: device_t(mconfig, MSX_CART_SFG01, "MSX Cartridge - SFG01", tag, owner, clock, "msx_cart_sfg01", __FILE__)
+	, msx_cart_interface(mconfig, *this)
+	, m_region_sfg01(*this, "sfg01")
+	, m_ym2151(*this, "ym2151")
+	, m_kbdc(*this, "kbdc")
+	, m_ym2151_irq_state(CLEAR_LINE)
+	, m_ym2148_irq_state(CLEAR_LINE)
+{
+}
+
+
+static MACHINE_CONFIG_FRAGMENT( msx_sfg01 )
+	// YM2151 (OPM)
+	// YM3012 (DAC)
+	// YM2148 (MKS)
+
+	MCFG_SPEAKER_STANDARD_STEREO("lspeaker", "rspeaker")
+	MCFG_YM2151_ADD("ym2151", XTAL_4MHz)
+	MCFG_YM2151_IRQ_HANDLER(WRITELINE(msx_cart_sfg01, ym2151_irq_w))
+//	MCFG_YM2151_PORT_WRITE_HANDLER(WRITE8(msx_cart_sfg01, port_w))
+	MCFG_SOUND_ROUTE(0, "lspeaker", 0.50)
+	MCFG_SOUND_ROUTE(1, "rspeaker", 0.50)
+
+	MCFG_MSX_AUDIO_KBDC_PORT_ADD("kbdc", msx_audio_keyboards, NULL)
+MACHINE_CONFIG_END
+
+
+machine_config_constructor msx_cart_sfg01::device_mconfig_additions() const
+{
+	return MACHINE_CONFIG_NAME( msx_sfg01 );
+}
+
+
+ROM_START( msx_sfg01 )
+	ROM_REGION(0x4000, "sfg01", 0)
+	ROM_LOAD("sfg01.rom", 0x0, 0x4000, CRC(0995fb36) SHA1(434651305f92aa770a89e40b81125fb22d91603d))
+ROM_END
+
+
+const rom_entry *msx_cart_sfg01::device_rom_region() const
+{
+	return ROM_NAME( msx_sfg01 );
+}
+
+
+void msx_cart_sfg01::device_start()
+{
+}
+
+
+void msx_cart_sfg01::initialize_cartridge()
+{
+}
+
+
+WRITE_LINE_MEMBER(msx_cart_sfg01::ym2151_irq_w)
+{
+	m_ym2151_irq_state = state ? ASSERT_LINE : CLEAR_LINE;
+	check_irq();
+}
+
+
+WRITE_LINE_MEMBER(msx_cart_sfg01::ym2148_irq_w)
+{
+	m_ym2148_irq_state = state ? ASSERT_LINE : CLEAR_LINE;
+	check_irq();
+}
+
+
+void msx_cart_sfg01::check_irq()
+{
+	if (m_ym2151_irq_state != CLEAR_LINE || m_ym2148_irq_state != CLEAR_LINE)
+	{
+		m_out_irq_cb(ASSERT_LINE);
+	}
+	else
+	{
+		m_out_irq_cb(CLEAR_LINE);
+	}
+}
+
+
+READ8_MEMBER(msx_cart_sfg01::read_cart)
+{
+	switch (offset)
+	{
+		case 0x3ff0:     // YM-2151 status read
+		case 0x3ff1:	 // YM-2151 status read mirror?
+			return m_ym2151->status_r(space, 0);
+
+		case 0x3ff2:     // YM-2148 keyboard column read
+			return m_kbdc->read(space, 0);
+
+		case 0x3ff3:     // YM-2148 --
+		case 0x3ff4:     // YM-2148 --
+		case 0x3ff5:     // YM-2148 MIDI UART data read register
+		case 0x3ff6:     // YM-2148 MIDI UART status register
+			break;
+	}
+
+	if (offset < 0x8000)
+	{
+		return m_region_sfg01->u8(offset & 0x3fff);
+	}
+
+	return 0xff;
+}
+
+
+WRITE8_MEMBER(msx_cart_sfg01::write_cart)
+{
+	switch (offset)
+	{
+		case 0x3ff0:     // YM-2151 register
+			m_ym2151->register_w(space, 0, data);
+			break;
+
+		case 0x3ff1:    // YM-2151 data
+			m_ym2151->data_w(space, 0, data);
+			break;
+
+		case 0x3ff2:   // YM-2148 write keyboard row
+			m_kbdc->write(space, 0, data);
+			break;
+
+		case 0x3ff3:   // YM-2148 MIDI IRQ vector
+		case 0x3ff4:   // YM-2148 External IRQ vector
+		case 0x3ff5:   // YM-2148 MIDI UART data write register
+		case 0x3ff6:   // YM-2148 MIDI UART command register
+		default:
+			logerror("msx_cart_sfg01::write_cart: write %02x to %04x\n", data, offset);
+			break;
+	}
+}
+
diff --git a/src/emu/bus/msx_cart/yamaha.h b/src/emu/bus/msx_cart/yamaha.h
new file mode 100644
index 00000000000..90e9b1b5f6c
--- /dev/null
+++ b/src/emu/bus/msx_cart/yamaha.h
@@ -0,0 +1,43 @@
+#ifndef __MSX_CART_YAMAHA_H
+#define __MSX_CART_YAMAHA_H
+
+#include "bus/msx_cart/cartridge.h"
+#include "sound/2151intf.h"
+#include "bus/msx_cart/msx_audio_kb.h"
+
+
+extern const device_type MSX_CART_SFG01;
+//extern const device_type MSX_CART_SFG05;
+
+
+class msx_cart_sfg01 : public device_t
+						, public msx_cart_interface
+{
+public:
+	msx_cart_sfg01(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+
+	// device-level overrides
+	virtual machine_config_constructor device_mconfig_additions() const;
+	virtual const rom_entry *device_rom_region() const;
+	virtual void device_start();
+
+	virtual void initialize_cartridge();
+
+	virtual DECLARE_READ8_MEMBER(read_cart);
+	virtual DECLARE_WRITE8_MEMBER(write_cart);
+
+	DECLARE_WRITE_LINE_MEMBER(ym2151_irq_w);
+	DECLARE_WRITE_LINE_MEMBER(ym2148_irq_w);
+
+private:
+	required_memory_region m_region_sfg01;
+	required_device<ym2151_device> m_ym2151;
+	required_device<msx_audio_kbdc_port_device> m_kbdc;
+	int m_ym2151_irq_state;
+	int m_ym2148_irq_state;
+
+	void check_irq();
+};
+
+#endif
+
diff --git a/src/emu/bus/msx_slot/cartridge.c b/src/emu/bus/msx_slot/cartridge.c
index 199d1c8a1b7..c3eabedcb9d 100644
--- a/src/emu/bus/msx_slot/cartridge.c
+++ b/src/emu/bus/msx_slot/cartridge.c
@@ -28,6 +28,7 @@ enum
 
 
 const device_type MSX_SLOT_CARTRIDGE = &device_creator<msx_slot_cartridge_device>;
+const device_type MSX_SLOT_YAMAHA_EXPANSION = &device_creator<msx_slot_yamaha_expansion_device>;
 
 
 msx_slot_cartridge_device::msx_slot_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
@@ -35,6 +36,19 @@ msx_slot_cartridge_device::msx_slot_cartridge_device(const machine_config &mconf
 	, device_image_interface(mconfig, *this)
 	, device_slot_interface(mconfig, *this)
 	, msx_internal_slot_interface()
+	, m_irq_handler(*this)
+	, m_cartridge(NULL)
+{
+}
+
+
+msx_slot_cartridge_device::msx_slot_cartridge_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source)
+	: device_t(mconfig, type, name, tag, owner, clock, shortname, source)
+	, device_image_interface(mconfig, *this)
+	, device_slot_interface(mconfig, *this)
+	, msx_internal_slot_interface()
+	, m_irq_handler(*this)
+	, m_cartridge(NULL)
 {
 }
 
@@ -81,6 +95,7 @@ static const char *msx_cart_get_slot_option(int type)
 
 void msx_slot_cartridge_device::device_start()
 {
+	m_irq_handler.resolve_safe();
 	m_cartridge = dynamic_cast<msx_cart_interface *>(get_card_device());
 }
 
@@ -133,6 +148,7 @@ bool msx_slot_cartridge_device::call_load()
 			}
 		}
 
+		m_cartridge->set_out_irq_cb(DEVCB_WRITELINE(msx_slot_cartridge_device, irq_out));
 		m_cartridge->initialize_cartridge();
 
 		if (m_cartridge->get_sram_size() > 0)
@@ -163,6 +179,12 @@ bool msx_slot_cartridge_device::call_softlist_load(software_list_device &swlist,
 }
 
 
+WRITE_LINE_MEMBER(msx_slot_cartridge_device::irq_out)
+{
+	m_irq_handler(state);
+}
+
+
 int msx_slot_cartridge_device::get_cart_type(UINT8 *rom, UINT32 length)
 {
 	if (length < 0x2000)
@@ -315,3 +337,23 @@ WRITE8_MEMBER(msx_slot_cartridge_device::write)
 	}
 }
 
+
+
+
+msx_slot_yamaha_expansion_device::msx_slot_yamaha_expansion_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+    : msx_slot_cartridge_device(mconfig, MSX_SLOT_YAMAHA_EXPANSION, "MSX Yamaha Expansion slot", tag, owner, clock, "msx_slot_yamaha_expansion", __FILE__)
+{
+}
+
+
+void msx_slot_yamaha_expansion_device::device_start()
+{
+	m_irq_handler.resolve_safe();
+	m_cartridge = dynamic_cast<msx_cart_interface *>(get_card_device());
+	if (m_cartridge)
+	{
+		m_cartridge->set_out_irq_cb(DEVCB_WRITELINE(msx_slot_cartridge_device, irq_out));
+	}
+}
+
+
diff --git a/src/emu/bus/msx_slot/cartridge.h b/src/emu/bus/msx_slot/cartridge.h
index 6716dc3ca14..1ca3ebfff61 100644
--- a/src/emu/bus/msx_slot/cartridge.h
+++ b/src/emu/bus/msx_slot/cartridge.h
@@ -6,11 +6,19 @@
 
 
 extern const device_type MSX_SLOT_CARTRIDGE;
+extern const device_type MSX_SLOT_YAMAHA_EXPANSION;
 
 
-#define MCFG_MSX_SLOT_CARTRIDGE_ADD(_tag) \
+#define MCFG_MSX_SLOT_CARTRIDGE_ADD(_tag, _devcb) \
 	MCFG_DEVICE_ADD(_tag, MSX_SLOT_CARTRIDGE, 0) \
-	MCFG_DEVICE_SLOT_INTERFACE(msx_cart, NULL, false)
+	MCFG_DEVICE_SLOT_INTERFACE(msx_cart, NULL, false) \
+	devcb = &msx_slot_cartridge_device::set_irq_handler(*device, DEVCB_##_devcb);
+
+
+#define MCFG_MSX_SLOT_YAMAHA_EXPANSION_ADD(_tag, _devcb) \
+	MCFG_DEVICE_ADD(_tag, MSX_SLOT_YAMAHA_EXPANSION, 0) \
+	MCFG_DEVICE_SLOT_INTERFACE(msx_yamaha_60pin, NULL, false) \
+	devcb = &msx_slot_cartridge_device::set_irq_handler(*device, DEVCB_##_devcb);
 
 
 class msx_slot_cartridge_device : public device_t
@@ -20,8 +28,12 @@ class msx_slot_cartridge_device : public device_t
 {
 public:
 	// construction/destruction
+	msx_slot_cartridge_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source);
 	msx_slot_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
 
+	// static configuration helpers
+	template<class _Object> static devcb_base &set_irq_handler(device_t &device, _Object object) { return downcast<msx_slot_cartridge_device &>(device).m_irq_handler.set_callback(object); }
+
 	// device-level overrides
 	virtual void device_start();
 	virtual void device_config_complete() { update_names(MSX_SLOT_CARTRIDGE, "cartridge", "cart"); }
@@ -47,11 +59,25 @@ public:
 	virtual DECLARE_READ8_MEMBER(read);
 	virtual DECLARE_WRITE8_MEMBER(write);
 
-private:
+	DECLARE_WRITE_LINE_MEMBER(irq_out);
+
+protected:
+	devcb_write_line m_irq_handler;
 	msx_cart_interface *m_cartridge;
 
 	int get_cart_type(UINT8 *rom, UINT32 length);
 };
 
+
+class msx_slot_yamaha_expansion_device : public msx_slot_cartridge_device
+{
+public:
+	// construction/destruction
+	msx_slot_yamaha_expansion_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+
+	virtual void device_start();
+};
+
+
 #endif
 
diff --git a/src/mess/drivers/msx.c b/src/mess/drivers/msx.c
index 5c3c6d8c961..42f2f3ea235 100644
--- a/src/mess/drivers/msx.c
+++ b/src/mess/drivers/msx.c
@@ -1244,7 +1244,7 @@ static MACHINE_CONFIG_DERIVED( msx_ntsc, msx )
 	/* Video hardware */
 	MCFG_DEVICE_ADD( "tms9928a", TMS9928A, XTAL_10_738635MHz / 2 )
  	MCFG_TMS9928A_VRAM_SIZE(0x4000)
-	MCFG_TMS9928A_OUT_INT_LINE_CB(INPUTLINE("maincpu", INPUT_LINE_IRQ0))
+	MCFG_TMS9928A_OUT_INT_LINE_CB(WRITELINE(msx_state,msx_irq_source0))
 	MCFG_TMS9928A_SCREEN_ADD_NTSC( "screen" )
 	MCFG_SCREEN_UPDATE_DEVICE("tms9928a", tms9928a_device, screen_update)
 MACHINE_CONFIG_END
@@ -1254,7 +1254,7 @@ static MACHINE_CONFIG_DERIVED( msx_pal, msx )
 	/* Video hardware */
 	MCFG_DEVICE_ADD( "tms9928a", TMS9929A, XTAL_10_738635MHz / 2 )
  	MCFG_TMS9928A_VRAM_SIZE(0x4000)
-	MCFG_TMS9928A_OUT_INT_LINE_CB(INPUTLINE("maincpu", INPUT_LINE_IRQ0))
+	MCFG_TMS9928A_OUT_INT_LINE_CB(WRITELINE(msx_state,msx_irq_source0))
 	MCFG_TMS9928A_SCREEN_ADD_PAL( "screen" )
 	MCFG_SCREEN_UPDATE_DEVICE("tms9928a", tms9928a_device, screen_update)
 MACHINE_CONFIG_END
@@ -1285,7 +1285,7 @@ static MACHINE_CONFIG_START( msx2, msx_state )
 
 	/* video hardware */
 	MCFG_V9938_ADD("v9938", "screen", 0x20000)
-	MCFG_V99X8_INTERRUPT_CALLBACK(WRITELINE(msx_state,msx_vdp_interrupt))
+	MCFG_V99X8_INTERRUPT_CALLBACK(WRITELINE(msx_state,msx_irq_source0))
 
 	MCFG_SCREEN_ADD("screen", RASTER)
 	MCFG_SCREEN_VIDEO_ATTRIBUTES(VIDEO_UPDATE_BEFORE_VBLANK)
@@ -1353,7 +1353,7 @@ static MACHINE_CONFIG_START( msx2p, msx_state )
 
 	/* video hardware */
 	MCFG_V9958_ADD("v9958", "screen", 0x20000)
-	MCFG_V99X8_INTERRUPT_CALLBACK(WRITELINE(msx_state,msx_vdp_interrupt))
+	MCFG_V99X8_INTERRUPT_CALLBACK(WRITELINE(msx_state,msx_irq_source0))
 
 	MCFG_SCREEN_ADD("screen", RASTER)
 	MCFG_SCREEN_VIDEO_ATTRIBUTES(VIDEO_UPDATE_BEFORE_VBLANK)
@@ -2774,12 +2774,14 @@ static MACHINE_CONFIG_DERIVED( cx5m, msx_pal )
 	// YM2149
 	// FDC: None, 0 drives
 	// 2 Cartridge slots
+	// 1 Expansion slot (60 pins interface instead of regular 50 pin cartridge interface)
 
 	MCFG_MSX_LAYOUT_ROM("bios", 0, 0, 0, 2, "maincpu", 0x0000)
 	MCFG_MSX_LAYOUT_RAM("ram", 0, 0, 2, 2)   /* 32KB RAM */
 	MCFG_MSX_LAYOUT_CARTRIDGE("cartslot1", 1, 0)
 	MCFG_MSX_LAYOUT_CARTRIDGE("cartslot2", 2, 0)
-	MCFG_MSX_LAYOUT_ROM("sfg", 3, 0, 0, 2, "maincpu", 0x8000)  /* SFG */
+	MCFG_MSX_LAYOUT_YAMAHA_EXPANSION("expansion", 3, 0)
+//	MCFG_MSX_LAYOUT_ROM("sfg", 3, 0, 0, 2, "maincpu", 0x8000)  /* SFG */
 
 	MCFG_FRAGMENT_ADD( msx1_cartlist )
 MACHINE_CONFIG_END
diff --git a/src/mess/includes/msx.h b/src/mess/includes/msx.h
index e910de14676..1facdb7aef4 100644
--- a/src/mess/includes/msx.h
+++ b/src/mess/includes/msx.h
@@ -53,7 +53,11 @@
 	msx_state::install_slot_pages(*owner, _prim, _sec, _page, _numpages, device);
 
 #define MCFG_MSX_LAYOUT_CARTRIDGE(_tag, _prim, _sec) \
-	MCFG_MSX_SLOT_CARTRIDGE_ADD(_tag) \
+	MCFG_MSX_SLOT_CARTRIDGE_ADD(_tag, WRITELINE(msx_state, msx_irq_source1)) \
+	msx_state::install_slot_pages(*owner, _prim, _sec, 0, 4, device);
+
+#define MCFG_MSX_LAYOUT_YAMAHA_EXPANSION(_tag, _prim, _sec) \
+	MCFG_MSX_SLOT_YAMAHA_EXPANSION_ADD(_tag, WRITELINE(msx_state, msx_irq_source2)) \
 	msx_state::install_slot_pages(*owner, _prim, _sec, 0, 4, device);
 
 #define MCFG_MSX_LAYOUT_RAM_MM(_tag, _prim, _sec, _total_size) \
@@ -148,6 +152,10 @@ public:
 		}
 		m_mouse[0] = m_mouse[1] = 0;
 		m_mouse_stat[0] = m_mouse_stat[1] = 0;
+		for (int i = 0; i < ARRAY_LENGTH(m_irq_state); i++)
+		{
+			m_irq_state[i] = CLEAR_LINE;
+		}
 	}
 
 	// static configuration helpers
@@ -218,7 +226,10 @@ public:
 	DECLARE_WRITE8_MEMBER(msx_ay8910_w);
 	void msx_memory_init();
 
-	DECLARE_WRITE_LINE_MEMBER(msx_vdp_interrupt);
+	DECLARE_WRITE_LINE_MEMBER(msx_irq_source0) { msx_irq_source(0, state); }  // usually tms9918/v9938/v9958
+	DECLARE_WRITE_LINE_MEMBER(msx_irq_source1) { msx_irq_source(1, state); }  // usually first cartridge slot
+	DECLARE_WRITE_LINE_MEMBER(msx_irq_source2) { msx_irq_source(2, state); }  // usually second cartridge slot
+	DECLARE_WRITE_LINE_MEMBER(msx_irq_source3) { msx_irq_source(3, state); }  // sometimes expansion slot
 
 protected:
 	virtual const address_space_config *memory_space_config(address_spacenum spacenum = AS_0) const { return (spacenum == 0) ? &m_switched_device_as_config : NULL; }
@@ -237,6 +248,12 @@ protected:
 	required_ioport m_io_key3;
 	required_ioport m_io_key4;
 	required_ioport m_io_key5;
+
+private:
+	int m_irq_state[4];
+
+	void msx_irq_source(int source, int level);
+	void check_irq();
 };
 
 
diff --git a/src/mess/machine/msx.c b/src/mess/machine/msx.c
index 9b635c9fb2f..5cc78cfa073 100644
--- a/src/mess/machine/msx.c
+++ b/src/mess/machine/msx.c
@@ -16,15 +16,40 @@
 #define VERBOSE 0
 
 
-WRITE_LINE_MEMBER(msx_state::msx_vdp_interrupt)
+void msx_state::msx_irq_source(int source, int level)
 {
-	m_maincpu->set_input_line(0, (state ? ASSERT_LINE : CLEAR_LINE));
+	assert(source >= 0 && source < ARRAY_LENGTH(m_irq_state));
+
+	m_irq_state[source] = level;
+	check_irq();
 }
 
+
+void msx_state::check_irq()
+{
+	int state = CLEAR_LINE;
+
+	for (int i = 0; i < ARRAY_LENGTH(m_irq_state); i++)
+	{
+		if (m_irq_state[i] != CLEAR_LINE)
+		{
+			state = ASSERT_LINE;
+		}
+	}
+
+	m_maincpu->set_input_line(0, state);
+}
+
+
 void msx_state::msx_ch_reset_core ()
 {
 	msx_memory_reset ();
 	msx_memory_map_all ();
+	for (int i = 0; i < ARRAY_LENGTH(m_irq_state); i++)
+	{
+		m_irq_state[i] = CLEAR_LINE;
+	}
+	check_irq();
 }
 
 MACHINE_START_MEMBER(msx_state,msx)