diff --git a/src/mess/machine/cmdhd.c b/src/mess/machine/cmdhd.c
index e7b6c1bd9b9..ce01bde8d63 100644
--- a/src/mess/machine/cmdhd.c
+++ b/src/mess/machine/cmdhd.c
@@ -19,6 +19,8 @@
 #define M6522_1_TAG		"m6522_1"
 #define M6522_2_TAG		"m6522_2"
 #define I8255A_TAG		"i8255a"
+#define RTC72421A_TAG	"rtc"
+#define SCSIBUS_TAG		"scsi"
 
 
 
@@ -36,6 +38,11 @@ const device_type CMD_HD = &device_creator<cmd_hd_device>;
 ROM_START( cmd_hd )
 	ROM_REGION( 0x8000, M6502_TAG, 0 )
 	ROM_LOAD( "cmd_hd_bootrom_v280.bin", 0x0000, 0x8000, CRC(da68435d) SHA1(defd8bc04a52904b8a3560f11c82126619513a10) )
+
+	ROM_REGION( 0x104, "plds", 0 )
+	ROM_LOAD( "pal16l8_1", 0x000, 0x001, NO_DUMP )
+	ROM_LOAD( "pal16l8_2", 0x000, 0x001, NO_DUMP )
+	ROM_LOAD( "pal16l8_3", 0x000, 0x001, NO_DUMP )
 ROM_END
 
 
@@ -56,8 +63,11 @@ const rom_entry *cmd_hd_device::device_rom_region() const
 static ADDRESS_MAP_START( cmd_hd_mem, AS_PROGRAM, 8, cmd_hd_device )
 	AM_RANGE(0x0000, 0x7fff) AM_RAM
 	AM_RANGE(0x8000, 0xffff) AM_ROM AM_REGION(M6502_TAG, 0)
-	//AM_RANGE() AM_DEVREADWRITE(M6522_1_TAG, via6522_device, read, write)
-	//AM_RANGE() AM_DEVREADWRITE(M6522_2_TAG, via6522_device, read, write)
+	AM_RANGE(0x8000, 0x800f) AM_MIRROR(0x1f0) AM_DEVREADWRITE(M6522_1_TAG, via6522_device, read, write)
+	AM_RANGE(0x8400, 0x840f) AM_MIRROR(0x1f0) AM_DEVREADWRITE(M6522_2_TAG, via6522_device, read, write)
+	AM_RANGE(0x8800, 0x8803) AM_MIRROR(0x1fc) AM_DEVREADWRITE(I8255A_TAG, i8255_device, read, write)
+	AM_RANGE(0x8c00, 0x8c0f) AM_MIRROR(0x1f0) //AM_DEVREADWRITE(RTC72421A_TAG, rtc72421a_device, read, write)
+	AM_RANGE(0x8f00, 0x8f00) AM_MIRROR(0xff) AM_WRITE(led_w)
 ADDRESS_MAP_END
 
 
@@ -135,8 +145,11 @@ static MACHINE_CONFIG_FRAGMENT( cmd_hd )
 	MCFG_VIA6522_ADD(M6522_1_TAG, 2000000, via1_intf)
 	MCFG_VIA6522_ADD(M6522_2_TAG, 2000000, via2_intf)
 	MCFG_I8255A_ADD(I8255A_TAG, ppi_intf)
+	//MCFG_RTC72421A_ADD(RTC72421A_TAG)
 
-	MCFG_HARDDISK_ADD("harddisk0")
+	MCFG_SCSIBUS_ADD(SCSIBUS_TAG)
+	MCFG_SCSIDEV_ADD(SCSIBUS_TAG ":harddisk0", SCSIHD, SCSI_ID_0)
+	MCFG_SCSICB_ADD(SCSIBUS_TAG ":host")
 MACHINE_CONFIG_END
 
 
@@ -163,7 +176,8 @@ machine_config_constructor cmd_hd_device::device_mconfig_additions() const
 cmd_hd_device::cmd_hd_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
     : device_t(mconfig, CMD_HD, "HD", tag, owner, clock),
 	  device_cbm_iec_interface(mconfig, *this),
-	  m_maincpu(*this, M6502_TAG)
+	  m_maincpu(*this, M6502_TAG),
+	  m_scsibus(*this, SCSIBUS_TAG":host")
 {
 }
 
@@ -224,3 +238,26 @@ void cmd_hd_device::cbm_iec_reset(int state)
 		device_reset();
 	}
 }
+
+
+//-------------------------------------------------
+//  led_w -
+//-------------------------------------------------
+
+WRITE8_MEMBER( cmd_hd_device::led_w )
+{
+	/*
+	
+	    bit     description
+	
+	    0       
+	    1       
+	    2       
+	    3       
+	    4       
+	    5       
+	    6       
+	    7       
+	
+	*/
+}
diff --git a/src/mess/machine/cmdhd.h b/src/mess/machine/cmdhd.h
index b535b40b54c..43e565dc2b4 100644
--- a/src/mess/machine/cmdhd.h
+++ b/src/mess/machine/cmdhd.h
@@ -12,14 +12,15 @@
 #ifndef __CMD_HD__
 #define __CMD_HD__
 
-#define ADDRESS_MAP_MODERN
-
 #include "emu.h"
 #include "cpu/m6502/m6502.h"
 #include "imagedev/harddriv.h"
 #include "machine/6522via.h"
 #include "machine/cbmiec.h"
 #include "machine/i8255.h"
+#include "machine/scsibus.h"
+#include "machine/scsicb.h"
+#include "machine/scsihd.h"
 
 
 
@@ -40,7 +41,6 @@
 class cmd_hd_device :  public device_t,
 					   public device_cbm_iec_interface
 {
-
 public:
     // construction/destruction
     cmd_hd_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
@@ -49,11 +49,13 @@ public:
 	virtual const rom_entry *device_rom_region() const;
 	virtual machine_config_constructor device_mconfig_additions() const;
 
+	DECLARE_WRITE8_MEMBER( led_w );
+
 protected:
     // device-level overrides
+    virtual void device_config_complete() { m_shortname = "cmdhd"; }
     virtual void device_start();
 	virtual void device_reset();
-    virtual void device_config_complete() { m_shortname = "cmdhd"; }
 
 	// device_cbm_iec_interface overrides
 	void cbm_iec_srq(int state);
@@ -62,6 +64,7 @@ protected:
 	void cbm_iec_reset(int state);
 
 	required_device<cpu_device> m_maincpu;
+	required_device<scsicb_device> m_scsibus;
 };