diff --git a/src/emu/cpu/tms34010/tms34010.c b/src/emu/cpu/tms34010/tms34010.c
index 5479f76d8dd..5cfd4aabdfd 100644
--- a/src/emu/cpu/tms34010/tms34010.c
+++ b/src/emu/cpu/tms34010/tms34010.c
@@ -1224,50 +1224,57 @@ WRITE16_MEMBER( tms34010_device::io_register_w )
 
 		case REG_HSTCTLH:
 			/* if the CPU is halting itself, stop execution right away */
-			if ((data & 0x8000) && !tms->external_host_access)
-				tms->icount = 0;
-			tms->device->set_input_line(INPUT_LINE_HALT, (data & 0x8000) ? ASSERT_LINE : CLEAR_LINE);
+			if (mem_mask & 0xff00)
+			{
+				if ((data & 0x8000) && !tms->external_host_access)
+					tms->icount = 0;
 
-			/* NMI issued? */
-			if (data & 0x0100)
-				tms->device->machine().scheduler().synchronize(FUNC(internal_interrupt_callback), 0, tms);
+				tms->device->set_input_line(INPUT_LINE_HALT, (data & 0x8000) ? ASSERT_LINE : CLEAR_LINE);
+
+				/* NMI issued? */
+				if (data & 0x0100)
+					tms->device->machine().scheduler().synchronize(FUNC(internal_interrupt_callback), 0, tms);
+			}
 			break;
 
 		case REG_HSTCTLL:
-			/* the TMS34010 can change MSGOUT, can set INTOUT, and can clear INTIN */
-			if (!tms->external_host_access)
+			if (mem_mask & 0x00ff)
 			{
-				newreg = (oldreg & 0xff8f) | (data & 0x0070);
-				newreg |= data & 0x0080;
-				newreg &= data | ~0x0008;
-			}
+				/* the TMS34010 can change MSGOUT, can set INTOUT, and can clear INTIN */
+				if (!tms->external_host_access)
+				{
+					newreg = (oldreg & 0xff8f) | (data & 0x0070);
+					newreg |= data & 0x0080;
+					newreg &= data | ~0x0008;
+				}
 
-			/* the host can change MSGIN, can set INTIN, and can clear INTOUT */
-			else
-			{
-				newreg = (oldreg & 0xfff8) | (data & 0x0007);
-				newreg &= data | ~0x0080;
-				newreg |= data & 0x0008;
-			}
-			IOREG(tms, offset) = newreg;
+				/* the host can change MSGIN, can set INTIN, and can clear INTOUT */
+				else
+				{
+					newreg = (oldreg & 0xfff8) | (data & 0x0007);
+					newreg &= data | ~0x0080;
+					newreg |= data & 0x0008;
+				}
+				IOREG(tms, offset) = newreg;
 
-			/* the TMS34010 can set output interrupt? */
-			if (!(oldreg & 0x0080) && (newreg & 0x0080))
-			{
-				if (tms->config->output_int)
-					(*tms->config->output_int)(&space.device(), 1);
-			}
-			else if ((oldreg & 0x0080) && !(newreg & 0x0080))
-			{
-				if (tms->config->output_int)
-					(*tms->config->output_int)(&space.device(), 0);
-			}
+				/* the TMS34010 can set output interrupt? */
+				if (!(oldreg & 0x0080) && (newreg & 0x0080))
+				{
+					if (tms->config->output_int)
+						(*tms->config->output_int)(&space.device(), 1);
+				}
+				else if ((oldreg & 0x0080) && !(newreg & 0x0080))
+				{
+					if (tms->config->output_int)
+						(*tms->config->output_int)(&space.device(), 0);
+				}
 
-			/* input interrupt? (should really be state-based, but the functions don't exist!) */
-			if (!(oldreg & 0x0008) && (newreg & 0x0008))
-				tms->device->machine().scheduler().synchronize(FUNC(internal_interrupt_callback), TMS34010_HI, tms);
-			else if ((oldreg & 0x0008) && !(newreg & 0x0008))
-				IOREG(tms, REG_INTPEND) &= ~TMS34010_HI;
+				/* input interrupt? (should really be state-based, but the functions don't exist!) */
+				if (!(oldreg & 0x0008) && (newreg & 0x0008))
+					tms->device->machine().scheduler().synchronize(FUNC(internal_interrupt_callback), TMS34010_HI, tms);
+				else if ((oldreg & 0x0008) && !(newreg & 0x0008))
+					IOREG(tms, REG_INTPEND) &= ~TMS34010_HI;
+			}
 			break;
 
 		case REG_CONVSP:
@@ -1588,8 +1595,9 @@ static void tms34010_state_postload(tms34010_state *tms)
     HOST INTERFACE WRITES
 ***************************************************************************/
 
-void tms34010_device::host_w(int reg, int data)
+WRITE16_MEMBER( tms34010_device::host_w )
 {
+	int reg = offset;
 	tms34010_state *tms = get_safe_token(this);
 	unsigned int addr;
 
@@ -1626,8 +1634,8 @@ void tms34010_device::host_w(int reg, int data)
 		{
 			tms->external_host_access = TRUE;
 			address_space &space = tms->device->space(AS_PROGRAM);
-			io_register_w(space, REG_HSTCTLH, data & 0xff00, 0xffff);
-			io_register_w(space, REG_HSTCTLL, data & 0x00ff, 0xffff);
+			if (mem_mask&0xff00) io_register_w(space, REG_HSTCTLH, data & 0xff00, 0xff00);
+			if (mem_mask&0x00ff) io_register_w(space, REG_HSTCTLL, data & 0x00ff, 0x00ff);
 			tms->external_host_access = FALSE;
 			break;
 		}
@@ -1645,12 +1653,13 @@ void tms34010_device::host_w(int reg, int data)
     HOST INTERFACE READS
 ***************************************************************************/
 
-int tms34010_device::host_r(int reg)
+READ16_MEMBER( tms34010_device::host_r )
 {
+	int reg = offset;
 	tms34010_state *tms = get_safe_token(this);
 	unsigned int addr;
 	int result = 0;
-
+	
 	/* swap to the target cpu */
 
 	switch (reg)
diff --git a/src/emu/cpu/tms34010/tms34010.h b/src/emu/cpu/tms34010/tms34010.h
index d3a3cd59cca..cc4f28de5b5 100644
--- a/src/emu/cpu/tms34010/tms34010.h
+++ b/src/emu/cpu/tms34010/tms34010.h
@@ -217,8 +217,8 @@ public:
 	DECLARE_WRITE16_MEMBER( io_register_w );
 	DECLARE_READ16_MEMBER( io_register_r );
 	
-	void  host_w(int reg, int data);
-	int   host_r(int reg);	
+	DECLARE_WRITE16_MEMBER(host_w);
+	DECLARE_READ16_MEMBER(host_r);
 };
 
 extern const device_type TMS34010;
diff --git a/src/mame/drivers/artmagic.c b/src/mame/drivers/artmagic.c
index c06bfa77159..e0fb0e17753 100644
--- a/src/mame/drivers/artmagic.c
+++ b/src/mame/drivers/artmagic.c
@@ -88,25 +88,6 @@ void artmagic_state::machine_reset()
 
 
 
-/*************************************
- *
- *  TMS34010 interface
- *
- *************************************/
-
-READ16_MEMBER(artmagic_state::tms_host_r)
-{
-	return m_tms->host_r(offset);
-}
-
-
-WRITE16_MEMBER(artmagic_state::tms_host_w)
-{
-	m_tms->host_w(offset, data);
-}
-
-
-
 /*************************************
  *
  *  Misc control memory accesses
@@ -439,7 +420,7 @@ static ADDRESS_MAP_START( main_map, AS_PROGRAM, 16, artmagic_state )
 	AM_RANGE(0x300000, 0x300003) AM_WRITE(control_w) AM_SHARE("control")
 	AM_RANGE(0x300004, 0x300007) AM_WRITE(protection_bit_w)
 	AM_RANGE(0x360000, 0x360001) AM_DEVREADWRITE8("oki", okim6295_device, read, write, 0x00ff)
-	AM_RANGE(0x380000, 0x380007) AM_READWRITE(tms_host_r, tms_host_w)
+	AM_RANGE(0x380000, 0x380007) AM_DEVREADWRITE("tms", tms34010_device, host_r, host_w)
 ADDRESS_MAP_END
 
 
@@ -458,7 +439,7 @@ static ADDRESS_MAP_START( stonebal_map, AS_PROGRAM, 16, artmagic_state )
 	AM_RANGE(0x300000, 0x300003) AM_WRITE(control_w) AM_SHARE("control")
 	AM_RANGE(0x300004, 0x300007) AM_WRITE(protection_bit_w)
 	AM_RANGE(0x340000, 0x340001) AM_DEVREADWRITE8("oki", okim6295_device, read, write, 0x00ff)
-	AM_RANGE(0x380000, 0x380007) AM_READWRITE(tms_host_r, tms_host_w)
+	AM_RANGE(0x380000, 0x380007) AM_DEVREADWRITE("tms", tms34010_device, host_r, host_w)
 ADDRESS_MAP_END
 
 READ16_MEMBER(artmagic_state::unk_r)
@@ -484,7 +465,7 @@ static ADDRESS_MAP_START( shtstar_map, AS_PROGRAM, 16, artmagic_state )
 	AM_RANGE(0x300000, 0x300003) AM_WRITE(control_w) AM_SHARE("control")
 	AM_RANGE(0x3c0004, 0x3c0007) AM_WRITE(protection_bit_w)
 	AM_RANGE(0x340000, 0x340001) AM_DEVREADWRITE8("oki", okim6295_device, read, write, 0x00ff)
-	AM_RANGE(0x380000, 0x380007) AM_READWRITE(tms_host_r, tms_host_w)
+	AM_RANGE(0x380000, 0x380007) AM_DEVREADWRITE("tms", tms34010_device, host_r, host_w)
 ADDRESS_MAP_END
 
 
diff --git a/src/mame/drivers/exterm.c b/src/mame/drivers/exterm.c
index 0e15386fd2a..29a3edde38e 100644
--- a/src/mame/drivers/exterm.c
+++ b/src/mame/drivers/exterm.c
@@ -78,13 +78,13 @@
 
 WRITE16_MEMBER(exterm_state::exterm_host_data_w)
 {
-	m_slave->host_w(offset / TOWORD(0x00100000), data);
+	m_slave->host_w(space,offset / TOWORD(0x00100000), data, 0xffff);
 }
 
 
 READ16_MEMBER(exterm_state::exterm_host_data_r)
 {
-	return m_slave->host_r(offset / TOWORD(0x00100000));
+	return m_slave->host_r(space,offset / TOWORD(0x00100000), 0xffff);
 }
 
 
diff --git a/src/mame/drivers/jpmimpct.c b/src/mame/drivers/jpmimpct.c
index 5be5eda9133..e8784e87600 100644
--- a/src/mame/drivers/jpmimpct.c
+++ b/src/mame/drivers/jpmimpct.c
@@ -167,22 +167,6 @@ MACHINE_RESET_MEMBER(jpmimpct_state,jpmimpct)
 }
 
 
-/*************************************
- *
- *  TMS34010 host interface
- *
- *************************************/
-
-WRITE16_MEMBER(jpmimpct_state::m68k_tms_w)
-{
-	m_dsp->host_w(offset, data);
-}
-
-READ16_MEMBER(jpmimpct_state::m68k_tms_r)
-{
-	return m_dsp->host_r(offset);
-}
-
 
 /*************************************
  *
@@ -614,7 +598,7 @@ static ADDRESS_MAP_START( m68k_program_map, AS_PROGRAM, 16, jpmimpct_state )
 	AM_RANGE(0x00480082, 0x00480083) AM_WRITE(volume_w)
 	AM_RANGE(0x00480084, 0x00480085) AM_READ(upd7759_r)
 	AM_RANGE(0x004801e0, 0x004801ff) AM_READWRITE(duart_2_r, duart_2_w)
-	AM_RANGE(0x00800000, 0x00800007) AM_READWRITE(m68k_tms_r, m68k_tms_w)
+	AM_RANGE(0x00800000, 0x00800007) AM_DEVREADWRITE("dsp", tms34010_device, host_r, host_w)
 	AM_RANGE(0x00c00000, 0x00cfffff) AM_ROM
 	AM_RANGE(0x00d00000, 0x00dfffff) AM_ROM
 	AM_RANGE(0x00e00000, 0x00efffff) AM_ROM
diff --git a/src/mame/drivers/littlerb.c b/src/mame/drivers/littlerb.c
index f9b490a14b4..e27205c135c 100644
--- a/src/mame/drivers/littlerb.c
+++ b/src/mame/drivers/littlerb.c
@@ -127,9 +127,6 @@ public:
 #if USE_TMS
 	required_shared_ptr<UINT16> m_vram;
 	required_device<palette_device> m_palette;
-
-	DECLARE_READ16_MEMBER(tms_host_r);
-	DECLARE_WRITE16_MEMBER(tms_host_w);
 #else
 	required_shared_ptr<UINT16> m_region4;
 	UINT16 m_vdp_address_low;
@@ -271,7 +268,7 @@ static ADDRESS_MAP_START( littlerb_main, AS_PROGRAM, 16, littlerb_state )
 	AM_RANGE(0x000000, 0x0fffff) AM_ROM
 	AM_RANGE(0x200000, 0x203fff) AM_RAM // main ram?
 #if USE_TMS
-	AM_RANGE(0x700000, 0x700007) AM_READWRITE(tms_host_r, tms_host_w)
+	AM_RANGE(0x700000, 0x700007) AM_DEVREADWRITE("tms", tms34010_device, host_r, host_w)
 #else
 	AM_RANGE(0x700000, 0x700007) AM_READ(littlerb_vdp_r) AM_WRITE(littlerb_vdp_w)
 #endif
@@ -401,15 +398,7 @@ TIMER_DEVICE_CALLBACK_MEMBER(littlerb_state::littlerb_scanline)
 
 
 #if USE_TMS
-READ16_MEMBER(littlerb_state::tms_host_r)
-{
-	return m_tms->host_r(offset);
-}
 
-WRITE16_MEMBER(littlerb_state::tms_host_w)
-{
-	m_tms->host_w(offset, data);
-}
 
 static ADDRESS_MAP_START( littlerb_tms_map, AS_PROGRAM, 16, littlerb_state )
 	AM_RANGE(0x00000000, 0x003fffff) AM_RAM AM_SHARE("vram")
diff --git a/src/mame/drivers/megaphx.c b/src/mame/drivers/megaphx.c
index bf5281abfc7..9b6caaf8442 100644
--- a/src/mame/drivers/megaphx.c
+++ b/src/mame/drivers/megaphx.c
@@ -110,9 +110,6 @@ public:
 
 	DECLARE_CUSTOM_INPUT_MEMBER(megaphx_rand_r);
 
-	DECLARE_READ16_MEMBER(tms_host_r);
-	DECLARE_WRITE16_MEMBER(tms_host_w);
-
 	DECLARE_READ16_MEMBER(megaphx_0x050002_r);
 	DECLARE_WRITE16_MEMBER(megaphx_0x050000_w);
 	DECLARE_READ8_MEMBER(megaphx_sound_sent_r);
@@ -175,16 +172,6 @@ CUSTOM_INPUT_MEMBER(megaphx_state::megaphx_rand_r)
 
 
 
-READ16_MEMBER(megaphx_state::tms_host_r)
-{
-	return m_tms->host_r(offset);
-}
-
-
-WRITE16_MEMBER(megaphx_state::tms_host_w)
-{
-	m_tms->host_w(offset, data);
-}
 
 READ16_MEMBER(megaphx_state::megaphx_0x050002_r)
 {
@@ -213,7 +200,7 @@ static ADDRESS_MAP_START( megaphx_68k_map, AS_PROGRAM, 16, megaphx_state )
 
 	AM_RANGE(0x000000, 0x03ffff) AM_ROM AM_REGION("roms67", 0x00000) // or the rom doesn't map here? it contains the service mode grid amongst other things..
 
-	AM_RANGE(0x040000, 0x040007) AM_READWRITE(tms_host_r, tms_host_w)
+	AM_RANGE(0x040000, 0x040007) AM_DEVREADWRITE("tms", tms34010_device, host_r, host_w)
 
 	AM_RANGE(0x050000, 0x050001) AM_WRITE(megaphx_0x050000_w) // z80 comms?
 	AM_RANGE(0x050002, 0x050003) AM_READ(megaphx_0x050002_r) // z80 comms?
@@ -735,7 +722,7 @@ static GFXDECODE_START( megaphx )
 	GFXDECODE_ENTRY( "roms67", 0, megaphxlay,     0x0000, 1 )
 GFXDECODE_END
 
-#define FAKE_BOOST 16
+#define FAKE_BOOST 1
 
 static MACHINE_CONFIG_START( megaphx, megaphx_state )
 
diff --git a/src/mame/drivers/micro3d.c b/src/mame/drivers/micro3d.c
index 2ccb27f5b5a..62d6937beaf 100644
--- a/src/mame/drivers/micro3d.c
+++ b/src/mame/drivers/micro3d.c
@@ -204,7 +204,7 @@ static ADDRESS_MAP_START( hostmem, AS_PROGRAM, 16, micro3d_state )
 	AM_RANGE(0x940000, 0x940001) AM_READ_PORT("INPUTS_A_B")
 	AM_RANGE(0x960000, 0x960001) AM_WRITE(micro3d_reset_w)
 	AM_RANGE(0x980000, 0x980001) AM_READWRITE(micro3d_adc_r, micro3d_adc_w)
-	AM_RANGE(0x9a0000, 0x9a0007) AM_READWRITE(micro3d_tms_host_r, micro3d_tms_host_w)
+	AM_RANGE(0x9a0000, 0x9a0007) AM_DEVREADWRITE("vgb", tms34010_device, host_r, host_w)
 	AM_RANGE(0x9c0000, 0x9c0001) AM_NOP                 /* Lamps */
 	AM_RANGE(0x9e0000, 0x9e002f) AM_DEVREADWRITE8("mc68901", mc68901_device, read, write, 0xff00)
 	AM_RANGE(0xa00000, 0xa0003f) AM_DEVREADWRITE8("duart68681", mc68681_device, read, write, 0xff00)
diff --git a/src/mame/drivers/skeetsht.c b/src/mame/drivers/skeetsht.c
index 913d72ff660..053896ffef4 100644
--- a/src/mame/drivers/skeetsht.c
+++ b/src/mame/drivers/skeetsht.c
@@ -131,13 +131,13 @@ WRITE8_MEMBER(skeetsht_state::tms_w)
 	if ((offset & 1) == 0)
 		m_lastdataw = data;
 	else
-		m_tms->host_w(offset >> 1, (m_lastdataw << 8) | data);
+		m_tms->host_w(space, offset >> 1, (m_lastdataw << 8) | data, 0xffff);
 }
 
 READ8_MEMBER(skeetsht_state::tms_r)
 {
 	if ((offset & 1) == 0)
-		m_lastdatar = m_tms->host_r(offset >> 1);
+		m_lastdatar = m_tms->host_r(space, offset >> 1, 0xffff);
 
 	return m_lastdatar >> ((offset & 1) ? 0 : 8);
 }
diff --git a/src/mame/drivers/skimaxx.c b/src/mame/drivers/skimaxx.c
index d226ea02fa4..25e7a8df602 100644
--- a/src/mame/drivers/skimaxx.c
+++ b/src/mame/drivers/skimaxx.c
@@ -66,8 +66,6 @@ public:
 	UINT32 m_blitter_src_dy;
 	DECLARE_WRITE32_MEMBER(skimaxx_blitter_w);
 	DECLARE_READ32_MEMBER(skimaxx_blitter_r);
-	DECLARE_WRITE32_MEMBER(m68k_tms_w);
-	DECLARE_READ32_MEMBER(m68k_tms_r);
 	DECLARE_WRITE32_MEMBER(skimaxx_fpga_ctrl_w);
 	DECLARE_READ32_MEMBER(unk_r);
 	DECLARE_READ32_MEMBER(skimaxx_unk1_r);
@@ -219,22 +217,6 @@ static void skimaxx_scanline_update(screen_device &screen, bitmap_ind16 &bitmap,
 }
 
 
-/*************************************
- *
- *  TMS34010 host interface
- *
- *************************************/
-
-WRITE32_MEMBER(skimaxx_state::m68k_tms_w)
-{
-	m_tms->host_w(offset, data);
-}
-
-READ32_MEMBER(skimaxx_state::m68k_tms_r)
-{
-	return m_tms->host_r(offset);
-}
-
 
 /*************************************
  *
@@ -316,7 +298,7 @@ READ32_MEMBER(skimaxx_state::skimaxx_analog_r)
 static ADDRESS_MAP_START( 68030_1_map, AS_PROGRAM, 32, skimaxx_state )
 	AM_RANGE(0x00000000, 0x001fffff) AM_ROM
 	AM_RANGE(0x10000000, 0x10000003) AM_WRITE(skimaxx_sub_ctrl_w )
-	AM_RANGE(0x10100000, 0x1010000f) AM_READWRITE(m68k_tms_r, m68k_tms_w)//AM_NOP
+	AM_RANGE(0x10100000, 0x1010000f) AM_DEVREADWRITE16("tms", tms34010_device, host_r, host_w, 0x0000ffff)
 //  AM_RANGE(0x10180000, 0x10187fff) AM_RAM AM_SHARE("share1")
 	AM_RANGE(0x10180000, 0x1018ffff) AM_RAM AM_SHARE("share1")  // above 10188000 accessed at level end (game bug?)
 	AM_RANGE(0x20000000, 0x20000003) AM_READNOP // watchdog_r?
diff --git a/src/mame/includes/artmagic.h b/src/mame/includes/artmagic.h
index d3ff346d924..e300ba1cb9b 100644
--- a/src/mame/includes/artmagic.h
+++ b/src/mame/includes/artmagic.h
@@ -47,8 +47,6 @@ public:
 	UINT16 m_blitter_data[8];
 	UINT8 m_blitter_page;
 	attotime m_blitter_busy_until;
-	DECLARE_READ16_MEMBER(tms_host_r);
-	DECLARE_WRITE16_MEMBER(tms_host_w);
 	DECLARE_WRITE16_MEMBER(control_w);
 	DECLARE_READ16_MEMBER(ultennis_hack_r);
 	DECLARE_WRITE16_MEMBER(protection_bit_w);
diff --git a/src/mame/includes/jpmimpct.h b/src/mame/includes/jpmimpct.h
index dfb954db8e2..74e7239f721 100644
--- a/src/mame/includes/jpmimpct.h
+++ b/src/mame/includes/jpmimpct.h
@@ -81,8 +81,6 @@ public:
 	optional_device<roc10937_t> m_vfd;
 	optional_shared_ptr<UINT16> m_vram;
 	struct bt477_t m_bt477;
-	DECLARE_WRITE16_MEMBER(m68k_tms_w);
-	DECLARE_READ16_MEMBER(m68k_tms_r);
 	DECLARE_READ16_MEMBER(duart_1_r);
 	DECLARE_WRITE16_MEMBER(duart_1_w);
 	DECLARE_READ16_MEMBER(duart_2_r);
diff --git a/src/mame/includes/micro3d.h b/src/mame/includes/micro3d.h
index 7ccee52fe94..24318daa57b 100644
--- a/src/mame/includes/micro3d.h
+++ b/src/mame/includes/micro3d.h
@@ -95,8 +95,6 @@ public:
 	DECLARE_READ16_MEMBER(micro3d_ti_uart_r);
 	DECLARE_WRITE32_MEMBER(micro3d_scc_w);
 	DECLARE_READ32_MEMBER(micro3d_scc_r);
-	DECLARE_READ16_MEMBER(micro3d_tms_host_r);
-	DECLARE_WRITE16_MEMBER(micro3d_tms_host_w);
 	DECLARE_WRITE32_MEMBER(micro3d_mac1_w);
 	DECLARE_READ32_MEMBER(micro3d_mac2_r);
 	DECLARE_WRITE32_MEMBER(micro3d_mac2_w);
diff --git a/src/mame/machine/harddriv.c b/src/mame/machine/harddriv.c
index 0061ce74387..66c7ef981a5 100644
--- a/src/mame/machine/harddriv.c
+++ b/src/mame/machine/harddriv.c
@@ -156,7 +156,7 @@ READ16_MEMBER( harddriv_state::hd68k_gsp_io_r )
 	UINT16 result;
 	offset = (offset / 2) ^ 1;
 	m_hd34010_host_access = TRUE;
-	result = m_gsp->host_r(offset);
+	result = m_gsp->host_r(space, offset, 0xffff);
 	m_hd34010_host_access = FALSE;
 	return result;
 }
@@ -166,7 +166,7 @@ WRITE16_MEMBER( harddriv_state::hd68k_gsp_io_w )
 {
 	offset = (offset / 2) ^ 1;
 	m_hd34010_host_access = TRUE;
-	m_gsp->host_w(offset, data);
+	m_gsp->host_w(space, offset, data, 0xffff);
 	m_hd34010_host_access = FALSE;
 }
 
@@ -183,7 +183,7 @@ READ16_MEMBER( harddriv_state::hd68k_msp_io_r )
 	UINT16 result;
 	offset = (offset / 2) ^ 1;
 	m_hd34010_host_access = TRUE;
-	result = (m_msp != NULL) ? m_msp->host_r(offset) : 0xffff;
+	result = (m_msp != NULL) ? m_msp->host_r(space, offset, 0xffff) : 0xffff;
 	m_hd34010_host_access = FALSE;
 	return result;
 }
@@ -195,7 +195,7 @@ WRITE16_MEMBER( harddriv_state::hd68k_msp_io_w )
 	if (m_msp != NULL)
 	{
 		m_hd34010_host_access = TRUE;
-		m_msp->host_w(offset, data);
+		m_msp->host_w(space, offset, data, 0xffff);
 		m_hd34010_host_access = FALSE;
 	}
 }
diff --git a/src/mame/machine/micro3d.c b/src/mame/machine/micro3d.c
index 17aa262aec2..de9d8ece400 100644
--- a/src/mame/machine/micro3d.c
+++ b/src/mame/machine/micro3d.c
@@ -205,22 +205,6 @@ READ32_MEMBER(micro3d_state::micro3d_scc_r)
 }
 
 
-/*************************************
- *
- *  Host<->TMS34010 interface
- *
- *************************************/
-
-READ16_MEMBER(micro3d_state::micro3d_tms_host_r)
-{
-	return m_vgb->host_r(offset);
-}
-
-WRITE16_MEMBER(micro3d_state::micro3d_tms_host_w)
-{
-	m_vgb->host_w(offset, data);
-}
-
 
 /*************************************
  *