diff --git a/src/mame/drivers/4roses.c b/src/mame/drivers/4roses.c
index 0abcb0ad2e5..03bba7c4544 100644
--- a/src/mame/drivers/4roses.c
+++ b/src/mame/drivers/4roses.c
@@ -353,19 +353,36 @@ static const ay8910_interface ay8910_intf =
 };
 
 
+/************************
+*    CRTC Interface    *
+************************/
+
+static const mc6845_interface mc6845_intf =
+{
+	"main",		/* screen we are acting on */
+	8,			/* number of pixels per video memory address */
+	NULL,		/* before pixel update callback */
+	NULL,		/* row update callback */
+	NULL,		/* after pixel update callback */
+	NULL,		/* callback for display state changes */
+	NULL,		/* HSYNC callback */
+	NULL		/* VSYNC callback */
+};
+
+
 /**************************
 *     Machine Drivers     *
 **************************/
 
 static MACHINE_DRIVER_START( 4roses )
-    /* basic machine hardware */
+	/* basic machine hardware */
 	MDRV_CPU_ADD("main", M65C02, MASTER_CLOCK/8)	/* 2MHz, guess */
 	MDRV_CPU_PROGRAM_MAP(4roses_map, 0)
 	MDRV_CPU_VBLANK_INT("main", nmi_line_pulse)
 
 //  MDRV_NVRAM_HANDLER(generic_0fill)
 
-    /* video hardware */
+	/* video hardware */
 
 	MDRV_SCREEN_ADD("main", RASTER)
 	MDRV_SCREEN_REFRESH_RATE(60)
@@ -381,9 +398,9 @@ static MACHINE_DRIVER_START( 4roses )
 	MDRV_VIDEO_START(funworld)
 	MDRV_VIDEO_UPDATE(funworld)
 
-	MDRV_MC6845_ADD("crtc", MC6845, 0, mc6845_null_interface)
+	MDRV_MC6845_ADD("crtc", MC6845, MASTER_CLOCK/8, mc6845_intf) /* 2MHz, guess */
 
-    /* sound hardware */
+	/* sound hardware */
 	MDRV_SPEAKER_STANDARD_MONO("mono")
 
 	MDRV_SOUND_ADD("ay8910", AY8910, MASTER_CLOCK/8)	/* 2MHz, guess */
diff --git a/src/mame/drivers/jokrwild.c b/src/mame/drivers/jokrwild.c
index 468feeea516..138aa0f954a 100644
--- a/src/mame/drivers/jokrwild.c
+++ b/src/mame/drivers/jokrwild.c
@@ -331,6 +331,24 @@ static const pia6821_interface pia1_intf =
 	0, 0
 };
 
+
+/************************
+*    CRTC Interface    *
+************************/
+
+static const mc6845_interface mc6845_intf =
+{
+	"main",		/* screen we are acting on */
+	8,			/* number of pixels per video memory address */
+	NULL,		/* before pixel update callback */
+	NULL,		/* row update callback */
+	NULL,		/* after pixel update callback */
+	NULL,		/* callback for display state changes */
+	NULL,		/* HSYNC callback */
+	NULL		/* VSYNC callback */
+};
+
+
 /*************************
 *    Machine Drivers     *
 *************************/
@@ -358,7 +376,7 @@ static MACHINE_DRIVER_START( jokrwild )
 	MDRV_VIDEO_START(jokrwild)
 	MDRV_VIDEO_UPDATE(jokrwild)
 
-	MDRV_MC6845_ADD("crtc", MC6845, 0, mc6845_null_interface)
+	MDRV_MC6845_ADD("crtc", MC6845, MASTER_CLOCK/16, mc6845_intf) /* guess */
 
 MACHINE_DRIVER_END
 
diff --git a/src/mame/drivers/magicfly.c b/src/mame/drivers/magicfly.c
index 35272fb1618..b6fcec21725 100644
--- a/src/mame/drivers/magicfly.c
+++ b/src/mame/drivers/magicfly.c
@@ -730,6 +730,23 @@ static GFXDECODE_START( magicfly )
 GFXDECODE_END
 
 
+/************************
+*    CRTC Interface    *
+************************/
+
+static const mc6845_interface mc6845_intf =
+{
+	"main",		/* screen we are acting on */
+	8,			/* number of pixels per video memory address */
+	NULL,		/* before pixel update callback */
+	NULL,		/* row update callback */
+	NULL,		/* after pixel update callback */
+	NULL,		/* callback for display state changes */
+	NULL,		/* HSYNC callback */
+	NULL		/* VSYNC callback */
+};
+
+
 /*************************
 *    Machine Drivers     *
 *************************/
@@ -758,7 +775,7 @@ static MACHINE_DRIVER_START( magicfly )
 	MDRV_VIDEO_START(magicfly)
 	MDRV_VIDEO_UPDATE(magicfly)
 
-	MDRV_MC6845_ADD("crtc", MC6845, 0, mc6845_null_interface)
+	MDRV_MC6845_ADD("crtc", MC6845, MASTER_CLOCK/16, mc6845_intf) /* guess */
 
 	/* sound hardware */
 	MDRV_SPEAKER_STANDARD_MONO("mono")
diff --git a/src/mame/drivers/miniboy7.c b/src/mame/drivers/miniboy7.c
index 6f06b9bc2b2..2f1598e0180 100644
--- a/src/mame/drivers/miniboy7.c
+++ b/src/mame/drivers/miniboy7.c
@@ -248,6 +248,23 @@ static GFXDECODE_START( miniboy7 )
 GFXDECODE_END
 
 
+/************************
+*    CRTC Interface    *
+************************/
+
+static const mc6845_interface mc6845_intf =
+{
+	"main",		/* screen we are acting on */
+	8,			/* number of pixels per video memory address */
+	NULL,		/* before pixel update callback */
+	NULL,		/* row update callback */
+	NULL,		/* after pixel update callback */
+	NULL,		/* callback for display state changes */
+	NULL,		/* HSYNC callback */
+	NULL		/* VSYNC callback */
+};
+
+
 /*************************
 *    Machine Drivers     *
 *************************/
@@ -274,7 +291,7 @@ static MACHINE_DRIVER_START( miniboy7 )
 	MDRV_VIDEO_START(miniboy7)
 	MDRV_VIDEO_UPDATE(miniboy7)
 
-	MDRV_MC6845_ADD("crtc", MC6845, 0, mc6845_null_interface)
+	MDRV_MC6845_ADD("crtc", MC6845, MASTER_CLOCK/11, mc6845_intf) /* guess */
 MACHINE_DRIVER_END
 
 
diff --git a/src/mame/drivers/murogem.c b/src/mame/drivers/murogem.c
index 73e1a89b66a..ff6772bf93a 100644
--- a/src/mame/drivers/murogem.c
+++ b/src/mame/drivers/murogem.c
@@ -192,6 +192,18 @@ static VIDEO_UPDATE(murogem)
 	return 0;
 }
 
+static const mc6845_interface mc6845_intf =
+{
+	"main",		/* screen we are acting on */
+	8,			/* number of pixels per video memory address */
+	NULL,		/* before pixel update callback */
+	NULL,		/* row update callback */
+	NULL,		/* after pixel update callback */
+	NULL,		/* callback for display state changes */
+	NULL,		/* HSYNC callback */
+	NULL		/* VSYNC callback */
+};
+
 
 static MACHINE_DRIVER_START( murogem )
 	/* basic machine hardware */
@@ -213,7 +225,7 @@ static MACHINE_DRIVER_START( murogem )
 	MDRV_PALETTE_INIT(murogem)
 	MDRV_VIDEO_UPDATE(murogem)
 
-	MDRV_MC6845_ADD("crtc", MC6845, 0, mc6845_null_interface)
+	MDRV_MC6845_ADD("crtc", MC6845, 750000, mc6845_intf) /* ? MHz */
 MACHINE_DRIVER_END
 
 
diff --git a/src/mame/drivers/raiden2.c b/src/mame/drivers/raiden2.c
index 0705218c049..0133651942a 100644
--- a/src/mame/drivers/raiden2.c
+++ b/src/mame/drivers/raiden2.c
@@ -1871,7 +1871,7 @@ ROM_START( xsedae )
 	ROM_LOAD32_BYTE("2.u025",   0x000001, 0x40000, CRC(a2b052df) SHA1(e8bf9ab3d5d4e601ea9386e1f2d4e017b025407e) )
 	ROM_LOAD32_BYTE("4.u026",   0x000003, 0x40000, CRC(5adf20bf) SHA1(42a0bb5a460c656675b2c432c043fc61a9049276) )
 
-	ROM_REGION( 0x40000, "user2", 0 )	/* COPDX */
+	ROM_REGION( 0x40000, "user2", ROMREGION_ERASEFF )	/* COPDX */
 	/* Not populated */
 
 	ROM_REGION( 0x20000, "audio", 0 ) /* 64k code for sound Z80 */