diff --git a/src/mame/drivers/cbuster.c b/src/mame/drivers/cbuster.c
index ea67e5a0312..5f15c26da01 100644
--- a/src/mame/drivers/cbuster.c
+++ b/src/mame/drivers/cbuster.c
@@ -291,9 +291,6 @@ static const deco16ic_interface twocrude_deco16ic_tilegen2_intf =
 
 void cbuster_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	save_item(NAME(m_prot));
 	save_item(NAME(m_pri));
 }
diff --git a/src/mame/drivers/dblewing.c b/src/mame/drivers/dblewing.c
index a04c1e1d64c..f6615335ed5 100644
--- a/src/mame/drivers/dblewing.c
+++ b/src/mame/drivers/dblewing.c
@@ -36,7 +36,8 @@ public:
 		m_spriteram(*this, "spriteram"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -81,7 +82,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_WRITE_LINE_MEMBER(sound_irq);
 	DECLARE_READ16_MEMBER(dblewing_prot_r);
 	DECLARE_WRITE16_MEMBER(dblewing_prot_w);
@@ -562,8 +563,6 @@ static const deco16ic_interface dblewing_deco16ic_tilegen1_intf =
 
 void dblewing_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-
 	save_item(NAME(m_008_data));
 	save_item(NAME(m_104_data));
 	save_item(NAME(m_406_data));
diff --git a/src/mame/drivers/dietgo.c b/src/mame/drivers/dietgo.c
index 64384a76bd4..40f94e7a9c8 100644
--- a/src/mame/drivers/dietgo.c
+++ b/src/mame/drivers/dietgo.c
@@ -184,7 +184,6 @@ static const deco16ic_interface dietgo_deco16ic_tilegen1_intf =
 
 void dietgo_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
 }
 
 static MACHINE_CONFIG_START( dietgo, dietgo_state )
diff --git a/src/mame/drivers/dreambal.c b/src/mame/drivers/dreambal.c
index 68eda3cb991..99696aebca2 100644
--- a/src/mame/drivers/dreambal.c
+++ b/src/mame/drivers/dreambal.c
@@ -33,14 +33,15 @@ public:
 	dreambal_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag),
 		m_eeprom(*this, "eeprom"),
-		m_maincpu(*this, "maincpu")
+		m_maincpu(*this, "maincpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	required_device<eeprom_device> m_eeprom;
 
 	/* devices */
 	required_device<cpu_device> m_maincpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 
 	DECLARE_DRIVER_INIT(dreambal);
 	virtual void machine_start();
@@ -283,9 +284,6 @@ static const deco16ic_interface dreambal_deco16ic_tilegen1_intf =
 
 void dreambal_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-
-
 }
 
 void dreambal_state::machine_reset()
diff --git a/src/mame/drivers/funkyjet.c b/src/mame/drivers/funkyjet.c
index cf1f9c050ae..d8f29408cec 100644
--- a/src/mame/drivers/funkyjet.c
+++ b/src/mame/drivers/funkyjet.c
@@ -288,8 +288,6 @@ static const deco16ic_interface funkyjet_deco16ic_tilegen1_intf =
 
 void funkyjet_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-
 	decoprot_reset(machine());
 }
 
diff --git a/src/mame/drivers/pktgaldx.c b/src/mame/drivers/pktgaldx.c
index 6ca0b64591f..27987765e3c 100644
--- a/src/mame/drivers/pktgaldx.c
+++ b/src/mame/drivers/pktgaldx.c
@@ -314,8 +314,6 @@ static const deco16ic_interface pktgaldx_deco16ic_tilegen1_intf =
 
 void pktgaldx_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-
 	decoprot_reset(machine());
 }
 
diff --git a/src/mame/drivers/supbtime.c b/src/mame/drivers/supbtime.c
index 5791dae740e..6103e89d31e 100644
--- a/src/mame/drivers/supbtime.c
+++ b/src/mame/drivers/supbtime.c
@@ -320,7 +320,6 @@ static const deco16ic_interface supbtime_deco16ic_tilegen1_intf =
 
 void supbtime_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
 }
 
 static MACHINE_CONFIG_START( supbtime, supbtime_state )
diff --git a/src/mame/drivers/tumblep.c b/src/mame/drivers/tumblep.c
index 467131c0f1b..55349187ad6 100644
--- a/src/mame/drivers/tumblep.c
+++ b/src/mame/drivers/tumblep.c
@@ -285,7 +285,6 @@ static const deco16ic_interface tumblep_deco16ic_tilegen1_intf =
 
 void tumblep_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
 }
 
 static MACHINE_CONFIG_START( tumblep, tumblep_state )
diff --git a/src/mame/drivers/vaportra.c b/src/mame/drivers/vaportra.c
index 09432122206..2fbd2684565 100644
--- a/src/mame/drivers/vaportra.c
+++ b/src/mame/drivers/vaportra.c
@@ -230,9 +230,6 @@ static const deco16ic_interface vaportra_deco16ic_tilegen2_intf =
 
 void vaportra_state::machine_start()
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	save_item(NAME(m_priority));
 }
 
diff --git a/src/mame/includes/cbuster.h b/src/mame/includes/cbuster.h
index 0419857c558..b3ff8f52a00 100644
--- a/src/mame/includes/cbuster.h
+++ b/src/mame/includes/cbuster.h
@@ -5,6 +5,7 @@
 *************************************************************************/
 
 #include "video/decospr.h"
+#include "video/deco16ic.h"
 
 class cbuster_state : public driver_device
 {
@@ -19,7 +20,9 @@ public:
 		m_spriteram16(*this, "spriteram16"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1"),
+		m_deco_tilegen2(*this, "tilegen2")
 	{ }
 
 	/* memory pointers */
@@ -40,8 +43,8 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
-	device_t *m_deco_tilegen2;
+	required_device<deco16ic_device> m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen2;
 	DECLARE_WRITE16_MEMBER(twocrude_control_w);
 	DECLARE_READ16_MEMBER(twocrude_control_r);
 	DECLARE_WRITE16_MEMBER(twocrude_palette_24bit_rg_w);
diff --git a/src/mame/includes/deco32.h b/src/mame/includes/deco32.h
index 50d7a1ad3cf..55d30214bb1 100644
--- a/src/mame/includes/deco32.h
+++ b/src/mame/includes/deco32.h
@@ -1,6 +1,7 @@
 #include "audio/decobsmt.h"
 #include "video/bufsprite.h"
 #include "video/decospr.h"
+#include "video/deco16ic.h"
 #include "machine/eeprom.h"
 #include "sound/okim6295.h"
 
@@ -24,7 +25,9 @@ public:
 		m_sprgen2(*this, "spritegen2"),
 		m_eeprom(*this, "eeprom"),
 		m_oki1(*this, "oki1"),
-		m_oki2(*this, "oki2")
+		m_oki2(*this, "oki2"),
+		m_deco_tilegen1(*this, "tilegen1"),
+		m_deco_tilegen2(*this, "tilegen2")
 	{ }
 
 	required_device<cpu_device> m_maincpu;
@@ -77,8 +80,8 @@ public:
 	UINT16    m_pf3_rowscroll[0x1000];
 	UINT16    m_pf4_rowscroll[0x1000];
 
-	device_t *m_deco_tilegen1;
-	device_t *m_deco_tilegen2;
+	required_device<deco16ic_device> m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen2;
 	UINT8 m_irq_source;
 	DECLARE_WRITE_LINE_MEMBER(sound_irq_nslasher);
 	DECLARE_READ32_MEMBER(deco32_irq_controller_r);
diff --git a/src/mame/includes/dietgo.h b/src/mame/includes/dietgo.h
index 0b4d9a62926..c7e744ebf2a 100644
--- a/src/mame/includes/dietgo.h
+++ b/src/mame/includes/dietgo.h
@@ -5,6 +5,7 @@
 *************************************************************************/
 
 #include "video/decospr.h"
+#include "video/deco16ic.h"
 
 class dietgo_state : public driver_device
 {
@@ -16,7 +17,8 @@ public:
 		m_spriteram(*this, "spriteram"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -29,7 +31,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_DRIVER_INIT(dietgo);
 	virtual void machine_start();
 	UINT32 screen_update_dietgo(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
diff --git a/src/mame/includes/funkyjet.h b/src/mame/includes/funkyjet.h
index f2db3cef49f..6a8c11c8beb 100644
--- a/src/mame/includes/funkyjet.h
+++ b/src/mame/includes/funkyjet.h
@@ -5,6 +5,7 @@
 *************************************************************************/
 
 #include "video/decospr.h"
+#include "video/deco16ic.h"
 
 class funkyjet_state : public driver_device
 {
@@ -16,7 +17,8 @@ public:
 		m_pf2_rowscroll(*this, "pf2_rowscroll"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -29,7 +31,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_DRIVER_INIT(funkyjet);
 	virtual void machine_start();
 	UINT32 screen_update_funkyjet(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
diff --git a/src/mame/includes/pktgaldx.h b/src/mame/includes/pktgaldx.h
index 44e8a157616..7a9775d180f 100644
--- a/src/mame/includes/pktgaldx.h
+++ b/src/mame/includes/pktgaldx.h
@@ -18,7 +18,8 @@ public:
 		m_pktgaldb_sprites(*this, "pktgaldb_spr"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_oki2(*this, "oki2")
+		m_oki2(*this, "oki2"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -34,7 +35,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<okim6295_device> m_oki2;
-	device_t *m_deco_tilegen1;
+	optional_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_READ16_MEMBER(pckgaldx_unknown_r);
 	DECLARE_READ16_MEMBER(pckgaldx_protection_r);
 	DECLARE_WRITE16_MEMBER(pktgaldx_oki_bank_w);
diff --git a/src/mame/includes/supbtime.h b/src/mame/includes/supbtime.h
index 0979dc2d235..b2f8563fbcd 100644
--- a/src/mame/includes/supbtime.h
+++ b/src/mame/includes/supbtime.h
@@ -16,7 +16,8 @@ public:
 		m_pf2_rowscroll(*this, "pf2_rowscroll"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -31,7 +32,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_READ16_MEMBER(supbtime_controls_r);
 	DECLARE_WRITE16_MEMBER(sound_w);
 	virtual void machine_start();
diff --git a/src/mame/includes/tumblep.h b/src/mame/includes/tumblep.h
index 2318e52fabd..2dbb012aeec 100644
--- a/src/mame/includes/tumblep.h
+++ b/src/mame/includes/tumblep.h
@@ -5,6 +5,7 @@
 *************************************************************************/
 
 #include "video/decospr.h"
+#include "video/deco16ic.h"
 
 class tumblep_state : public driver_device
 {
@@ -16,7 +17,8 @@ public:
 		m_pf2_rowscroll(*this, "pf2_rowscroll"),
 		m_sprgen(*this, "spritegen"),
 		m_maincpu(*this, "maincpu"),
-		m_audiocpu(*this, "audiocpu")
+		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1")
 	{ }
 
 	/* memory pointers */
@@ -29,7 +31,7 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen1;
 	DECLARE_READ16_MEMBER(tumblep_prot_r);
 	DECLARE_WRITE16_MEMBER(tumblep_sound_w);
 	DECLARE_WRITE16_MEMBER(jumppop_sound_w);
diff --git a/src/mame/includes/vaportra.h b/src/mame/includes/vaportra.h
index 6d394596ffb..a656638458c 100644
--- a/src/mame/includes/vaportra.h
+++ b/src/mame/includes/vaportra.h
@@ -13,6 +13,8 @@ public:
 		: driver_device(mconfig, type, tag),
 		m_maincpu(*this, "maincpu"),
 		m_audiocpu(*this, "audiocpu"),
+		m_deco_tilegen1(*this, "tilegen1"),
+		m_deco_tilegen2(*this, "tilegen2"),
 		m_spriteram(*this, "spriteram") { }
 
 	/* memory pointers */
@@ -27,8 +29,8 @@ public:
 	/* devices */
 	required_device<cpu_device> m_maincpu;
 	required_device<cpu_device> m_audiocpu;
-	device_t *m_deco_tilegen1;
-	device_t *m_deco_tilegen2;
+	required_device<deco16ic_device> m_deco_tilegen1;
+	required_device<deco16ic_device> m_deco_tilegen2;
 	required_device<buffered_spriteram16_device> m_spriteram;
 	DECLARE_WRITE16_MEMBER(vaportra_sound_w);
 	DECLARE_READ16_MEMBER(vaportra_control_r);
diff --git a/src/mame/video/deco32.c b/src/mame/video/deco32.c
index 7b032b182f2..9a454b94b66 100644
--- a/src/mame/video/deco32.c
+++ b/src/mame/video/deco32.c
@@ -568,9 +568,6 @@ void dragngun_state::screen_eof_dragngun(screen_device &screen, bool state)
 
 UINT32 deco32_state::screen_update_captaven(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	machine().tilemap().set_flip_all(flip_screen() ? (TILEMAP_FLIPY | TILEMAP_FLIPX) : 0);
 
 	machine().priority_bitmap.fill(0, cliprect);
@@ -604,9 +601,6 @@ UINT32 deco32_state::screen_update_captaven(screen_device &screen, bitmap_ind16
 
 UINT32 dragngun_state::screen_update_dragngun(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	bitmap.fill(get_black_pen(machine()), cliprect);
 
 	deco16ic_pf_update(m_deco_tilegen1, m_pf1_rowscroll, m_pf2_rowscroll);
@@ -643,9 +637,6 @@ UINT32 dragngun_state::screen_update_dragngun(screen_device &screen, bitmap_rgb3
 
 UINT32 deco32_state::screen_update_fghthist(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	machine().priority_bitmap.fill(0, cliprect);
 	bitmap.fill(machine().pens[0x000], cliprect); // Palette index not confirmed
 
@@ -818,9 +809,6 @@ void deco32_state::mixDualAlphaSprites(bitmap_rgb32 &bitmap, const rectangle &cl
 UINT32 deco32_state::screen_update_nslasher(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
 	int alphaTilemap=0;
-	m_deco_tilegen1 = machine().device("tilegen1");
-	m_deco_tilegen2 = machine().device("tilegen2");
-
 	deco16ic_pf_update(m_deco_tilegen1, m_pf1_rowscroll, m_pf2_rowscroll);
 	deco16ic_pf_update(m_deco_tilegen2, m_pf3_rowscroll, m_pf4_rowscroll);