Converting m_p_chargen into a required_region, part 1

src/mame/drivers/argo.cpp

@@ -39,6 +39,7 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
 		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
 	DECLARE_WRITE8_MEMBER(argo_videoram_w);
@@ -50,7 +51,7 @@ public:
 private:
 	required_device<cpu_device> m_maincpu;
 	required_shared_ptr<uint8_t> m_p_videoram;
-	const uint8_t *m_p_chargen;
+	required_region_ptr<u8> m_p_chargen;
 	uint8_t m_framecnt;
 	uint8_t m_cursor_pos[3];
 	uint8_t m_p_cursor_pos;
@@ -58,8 +59,6 @@ private:
 	uint8_t m_scroll_ctrl;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-
-protected:
 	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 };
 
@@ -287,7 +286,6 @@ DRIVER_INIT_MEMBER(argo_state,argo)
 
 void argo_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t argo_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/beehive.cpp

@@ -31,6 +31,7 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
 		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
 	DECLARE_READ8_MEMBER(beehive_60_r);
@@ -39,8 +40,8 @@ public:
 
 private:
 	required_device<cpu_device> m_maincpu;
-	const uint8_t *m_p_chargen;
 	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 	uint8_t m_keyline;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
@@ -234,7 +235,6 @@ void beehive_state::machine_reset()
 
 void beehive_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 /* This system appears to have inline attribute bytes of unknown meaning.

src/mame/drivers/c10.cpp

@@ -28,14 +28,15 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
 		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
 	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
 	DECLARE_DRIVER_INIT(c10);
 private:
 	required_device<cpu_device> m_maincpu;
-	const uint8_t *m_p_chargen;
 	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
 
@@ -83,7 +84,6 @@ void c10_state::machine_reset()
 
 void c10_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 /* This system appears to have inline attribute bytes of unknown meaning.

src/mame/drivers/cdc721.cpp

@@ -20,6 +20,7 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_p_videoram(*this, "videoram")
 		, m_maincpu(*this, "maincpu")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
 	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
@@ -27,11 +28,9 @@ public:
 
 private:
 	virtual void machine_reset() override;
-	const uint8_t *m_p_chargen;
 	required_shared_ptr<uint8_t> m_p_videoram;
 	required_device<cpu_device> m_maincpu;
-
+	required_region_ptr<u8> m_p_chargen;
-
 };
 
 static ADDRESS_MAP_START( cdc721_mem, AS_PROGRAM, 8, cdc721_state )
@@ -49,7 +48,6 @@ INPUT_PORTS_END
 
 void cdc721_state::machine_reset()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 /* F4 Character Displayer */

src/mame/drivers/grfd2301.cpp

@@ -41,17 +41,16 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_p_videoram(*this, "videoram")
 		, m_maincpu(*this, "maincpu")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
-public:
-	virtual void machine_reset() override;
-	const uint8_t *m_p_chargen;
 	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	required_shared_ptr<uint8_t> m_p_videoram;
+
 private:
+	virtual void machine_reset() override;
+	required_shared_ptr<uint8_t> m_p_videoram;
 	required_device<cpu_device> m_maincpu;
-
+	required_region_ptr<u8> m_p_chargen;
-
 };
 
 static ADDRESS_MAP_START( grfd2301_mem, AS_PROGRAM, 8, grfd2301_state )
@@ -69,7 +68,6 @@ INPUT_PORTS_END
 
 void grfd2301_state::machine_reset()
 {
-	m_p_chargen = memregion("chargen")->base();
 	m_maincpu->set_pc(0xe000);
 }
 

src/mame/drivers/h19.cpp

@@ -85,34 +85,35 @@ public:
 	};
 
 	h19_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu"),
+		, m_palette(*this, "palette")
-		m_crtc(*this, "crtc"),
+		, m_maincpu(*this, "maincpu")
-		m_ace(*this, "ins8250"),
+		, m_crtc(*this, "crtc")
-		m_beep(*this, "beeper"),
+		, m_ace(*this, "ins8250")
-		m_p_videoram(*this, "videoram"),
+		, m_beep(*this, "beeper")
-		m_palette(*this, "palette")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
-	required_device<cpu_device> m_maincpu;
-	required_device<mc6845_device> m_crtc;
-	required_device<ins8250_device> m_ace;
-	required_device<beep_device> m_beep;
 	DECLARE_READ8_MEMBER(h19_80_r);
 	DECLARE_READ8_MEMBER(h19_a0_r);
 	DECLARE_WRITE8_MEMBER(h19_c0_w);
 	DECLARE_WRITE8_MEMBER(h19_kbd_put);
 	MC6845_UPDATE_ROW(crtc_update_row);
-	required_shared_ptr<uint8_t> m_p_videoram;
+
-	required_device<palette_device> m_palette;
+private:
-	uint8_t *m_p_chargen;
 	uint8_t m_term_data;
+	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-
+	required_device<palette_device> m_palette;
-protected:
+	required_device<cpu_device> m_maincpu;
-	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
+	required_device<mc6845_device> m_crtc;
+	required_device<ins8250_device> m_ace;
+	required_device<beep_device> m_beep;
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -347,7 +348,6 @@ void h19_state::machine_reset()
 
 void h19_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 MC6845_UPDATE_ROW( h19_state::crtc_update_row )

src/mame/drivers/homez80.cpp

@@ -31,12 +31,13 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
 		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 		{ }
 
 	required_device<cpu_device> m_maincpu;
 	DECLARE_READ8_MEMBER( homez80_keyboard_r );
 	required_shared_ptr<uint8_t> m_p_videoram;
-	uint8_t* m_p_chargen;
+	required_region_ptr<u8> m_p_chargen;
 	bool m_irq;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
@@ -220,7 +221,6 @@ void homez80_state::machine_reset()
 
 void homez80_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t homez80_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/ibm6580.cpp

@@ -142,6 +142,7 @@ public:
 		, m_fdc(*this, UPD765_TAG)
 		, m_flop0(*this, UPD765_TAG ":0")
 		, m_flop1(*this, UPD765_TAG ":1")
+		, m_p_chargen(*this, "chargen")
 	{ }
 
 	DECLARE_PALETTE_INIT(ibm6580);
@@ -182,7 +183,6 @@ private:
 	virtual void machine_reset() override;
 	virtual void video_start() override;
 
-	const uint8_t *m_p_chargen;
 	uint8_t m_p40, m_p50, m_e000, m_kb_data, m_ppi_c;
 	bool m_kb_data_bit, m_kb_strobe;
 	util::fifo<uint8_t, 4> m_kb_fifo;
@@ -208,6 +208,7 @@ private:
 	required_device<upd765a_device> m_fdc;
 	required_device<floppy_connector> m_flop0;
 	required_device<floppy_connector> m_flop1;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -839,7 +840,6 @@ PALETTE_INIT_MEMBER( ibm6580_state, ibm6580 )
 void ibm6580_state::machine_start()
 {
 	m_fdc->set_rate(500000);
-	m_p_chargen = memregion("chargen")->base();
 }
 
 void ibm6580_state::machine_reset()

src/mame/drivers/k8915.cpp

@@ -18,25 +18,28 @@ class k8915_state : public driver_device
 {
 public:
 	k8915_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_p_videoram(*this, "videoram")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
-	required_device<cpu_device> m_maincpu;
 	DECLARE_READ8_MEMBER(k8915_52_r);
 	DECLARE_READ8_MEMBER(k8915_53_r);
 	DECLARE_WRITE8_MEMBER(k8915_a8_w);
 	DECLARE_WRITE8_MEMBER(kbd_put);
-	required_shared_ptr<uint8_t> m_p_videoram;
+	DECLARE_DRIVER_INIT(k8915);
-	uint8_t *m_p_chargen;
+	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
+private:
 	uint8_t m_framecnt;
 	uint8_t m_term_data;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	required_device<cpu_device> m_maincpu;
-	DECLARE_DRIVER_INIT(k8915);
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 READ8_MEMBER( k8915_state::k8915_52_r )
@@ -93,7 +96,6 @@ DRIVER_INIT_MEMBER(k8915_state,k8915)
 
 void k8915_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t k8915_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/mes.cpp

@@ -16,16 +16,20 @@ class mes_state : public driver_device
 {
 public:
 	mes_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-	m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-	m_p_videoram(*this, "videoram"){ }
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
+		{ }
 
-	required_device<cpu_device> m_maincpu;
+	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	const uint8_t *m_p_chargen;
+
-	required_shared_ptr<uint8_t> m_p_videoram;
+private:
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	required_device<cpu_device> m_maincpu;
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -51,7 +55,6 @@ void mes_state::machine_reset()
 
 void mes_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 /* This system appears to have 2 screens. Not implemented.

src/mame/drivers/modellot.cpp

@@ -24,9 +24,10 @@ class modellot_state : public driver_device
 {
 public:
 	modellot_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_p_videoram(*this, "videoram"),
+		, m_p_videoram(*this, "videoram")
-		m_maincpu(*this, "maincpu")
+		, m_maincpu(*this, "maincpu")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -34,12 +35,13 @@ public:
 	DECLARE_READ8_MEMBER(portff_r);
 	DECLARE_WRITE8_MEMBER(kbd_put);
 	uint32_t screen_update_modellot(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	required_shared_ptr<uint8_t> m_p_videoram;
+
 private:
 	uint8_t m_term_data;
-	const uint8_t *m_p_chargen;
 	virtual void machine_reset() override;
+	required_shared_ptr<uint8_t> m_p_videoram;
 	required_device<cpu_device> m_maincpu;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 static ADDRESS_MAP_START(modellot_mem, AS_PROGRAM, 8, modellot_state)
@@ -81,7 +83,6 @@ WRITE8_MEMBER( modellot_state::kbd_put )
 void modellot_state::machine_reset()
 {
 	m_term_data = 1;
-	m_p_chargen = memregion("chargen")->base();
 	m_maincpu->set_state_int(Z80_PC, 0xe000);
 }
 

src/mame/drivers/mx2178.cpp

@@ -29,12 +29,13 @@
 class mx2178_state : public driver_device
 {
 public:
-	mx2178_state(const machine_config &mconfig, device_type type, const char *tag) :
+	mx2178_state(const machine_config &mconfig, device_type type, const char *tag)
-		driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_p_videoram(*this, "videoram"),
+		, m_palette(*this, "palette")
-		m_maincpu(*this, "maincpu"),
+		, m_p_videoram(*this, "videoram")
-		m_acia(*this, "acia"),
+		, m_maincpu(*this, "maincpu")
-		m_palette(*this, "palette")
+		, m_acia(*this, "acia")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -43,18 +44,14 @@ public:
 	DECLARE_WRITE_LINE_MEMBER(write_acia_clock);
 	MC6845_UPDATE_ROW(crtc_update_row);
 
-	const uint8_t *m_p_chargen;
-	required_shared_ptr<uint8_t> m_p_videoram;
-
-protected:
-	virtual void machine_reset() override;
-
 private:
 	uint8_t m_term_data;
+	virtual void machine_reset() override;
+	required_device<palette_device> m_palette;
+	required_shared_ptr<uint8_t> m_p_videoram;
 	required_device<z80_device> m_maincpu;
 	required_device<acia6850_device> m_acia;
-public:
+	required_region_ptr<u8> m_p_chargen;
-	required_device<palette_device> m_palette;
 };
 
 static ADDRESS_MAP_START(mx2178_mem, AS_PROGRAM, 8, mx2178_state)
@@ -144,7 +141,6 @@ GFXDECODE_END
 
 void mx2178_state::machine_reset()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 WRITE_LINE_MEMBER(mx2178_state::write_acia_clock)

src/mame/drivers/phunsy.cpp

@@ -41,11 +41,12 @@ class phunsy_state : public driver_device
 {
 public:
 	phunsy_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_speaker(*this, "speaker"),
+		, m_speaker(*this, "speaker")
-		m_cass(*this, "cassette"),
+		, m_cass(*this, "cassette")
-		m_p_videoram(*this, "videoram")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -59,8 +60,8 @@ public:
 	DECLARE_QUICKLOAD_LOAD_MEMBER(phunsy);
 	DECLARE_PALETTE_INIT(phunsy);
 	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
 private:
-	const uint8_t *m_p_chargen;
 	uint8_t       m_data_out;
 	uint8_t       m_keyboard_input;
 	virtual void machine_reset() override;
@@ -69,6 +70,7 @@ private:
 	required_device<speaker_sound_device> m_speaker;
 	required_device<cassette_image_device> m_cass;
 	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -206,7 +208,6 @@ PALETTE_INIT_MEMBER(phunsy_state, phunsy)
 
 void phunsy_state::video_start()
 {
-	m_p_chargen = memregion( "chargen" )->base();
 }
 
 

src/mame/drivers/plan80.cpp

@@ -39,21 +39,22 @@ public:
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
 		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{ }
 
-	required_device<cpu_device> m_maincpu;
 	DECLARE_READ8_MEMBER(plan80_04_r);
 	DECLARE_WRITE8_MEMBER(plan80_09_w);
-	required_shared_ptr<uint8_t> m_p_videoram;
+	DECLARE_DRIVER_INIT(plan80);
-	const uint8_t* m_p_chargen;
+	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
+private:
+	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 	uint8_t m_kbd_row;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	required_device<cpu_device> m_maincpu;
-	DECLARE_DRIVER_INIT(plan80);
+	required_shared_ptr<uint8_t> m_p_videoram;
-
+	required_region_ptr<u8> m_p_chargen;
-protected:
-	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 };
 
 READ8_MEMBER( plan80_state::plan80_04_r )
@@ -176,7 +177,6 @@ DRIVER_INIT_MEMBER(plan80_state,plan80)
 
 void plan80_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t plan80_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/tavernie.cpp

@@ -65,17 +65,18 @@ Z - more scan lines per row (cursor is bigger)
 class tavernie_state : public driver_device
 {
 public:
-	tavernie_state(const machine_config &mconfig, device_type type, const char *tag) :
+	tavernie_state(const machine_config &mconfig, device_type type, const char *tag)
-		driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_p_videoram(*this, "videoram"),
+		, m_p_videoram(*this, "videoram")
-		m_cass(*this, "cassette"),
+		, m_cass(*this, "cassette")
-		m_pia_ivg(*this, "pia_ivg"),
+		, m_pia_ivg(*this, "pia_ivg")
-		m_fdc(*this, "fdc"),
+		, m_fdc(*this, "fdc")
-		m_floppy0(*this, "fdc:0"),
+		, m_floppy0(*this, "fdc:0")
-		m_beep(*this, "beeper"),
+		, m_beep(*this, "beeper")
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_acia(*this, "acia"),
+		, m_acia(*this, "acia")
-		m_palette(*this, "palette")
+		, m_palette(*this, "palette")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -92,12 +93,10 @@ public:
 	DECLARE_WRITE_LINE_MEMBER(write_acia_clock);
 	MC6845_UPDATE_ROW(crtc_update_row);
 
-	const uint8_t *m_p_chargen;
-	optional_shared_ptr<uint8_t> m_p_videoram;
-
 private:
 	uint8_t m_term_data;
 	uint8_t m_pa;
+	optional_shared_ptr<uint8_t> m_p_videoram;
 	required_device<cassette_image_device> m_cass;
 	optional_device<pia6821_device> m_pia_ivg;
 	optional_device<fd1795_t> m_fdc;
@@ -105,8 +104,8 @@ private:
 	optional_device<beep_device> m_beep;
 	required_device<cpu_device> m_maincpu;
 	required_device<acia6850_device> m_acia;
-public:
 	optional_device<palette_device> m_palette;
+	optional_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -176,7 +175,6 @@ MACHINE_RESET_MEMBER( tavernie_state, cpu09)
 
 MACHINE_RESET_MEMBER( tavernie_state, ivg09)
 {
-	m_p_chargen = memregion("chargen")->base();
 	m_beep->set_state(1);
 	m_term_data = 0;
 	m_pia_ivg->cb1_w(1);

src/mame/drivers/ts803.cpp

@@ -71,6 +71,7 @@ public:
 		//, m_sti(*this, "sti")
 		, m_dart(*this, "dart")
 		, m_crtc(*this,"crtc")
+		, m_p_chargen(*this, "chargen")
 	{ }
 
 	DECLARE_READ8_MEMBER( ts803_port_r );
@@ -90,7 +91,6 @@ public:
 	TIMER_DEVICE_CALLBACK_MEMBER(dart_tick);
 
 	uint32_t screen_update_ts803(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	required_device<palette_device> m_palette;
 
 private:
 
@@ -100,11 +100,11 @@ private:
 	uint8_t m_sioarr[256];
 	bool m_graphics_mode;
 	bool m_tick;
-	uint8_t *m_p_chargen;
 
 	virtual void machine_reset() override;
 	virtual void machine_start() override;
 
+	required_device<palette_device> m_palette;
 	required_device<cpu_device> m_maincpu;
 	required_device<fd1793_t> m_fdc;
 	required_device<floppy_connector> m_floppy0;
@@ -112,6 +112,7 @@ private:
 	//required_device<z80sti_device> m_sti;
 	required_device<z80dart_device> m_dart;
 	required_device<sy6545_1_device> m_crtc;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 static ADDRESS_MAP_START(ts803_mem, AS_PROGRAM, 8, ts803_state)
@@ -462,7 +463,6 @@ DRIVER_INIT_MEMBER( ts803_state, ts803 )
 	m_videoram = std::make_unique<uint8_t[]>(0x8000);
 	m_56kram = std::make_unique<uint8_t[]>(0xc000);
 
-	m_p_chargen = memregion("chargen")->base();
 	uint8_t *rom = memregion("roms")->base();
 	membank("bankr0")->configure_entry(0, &rom[0]); // rom
 	membank("bankr0")->configure_entry(1, m_56kram.get()); // ram

src/mame/drivers/unior.cpp

@@ -49,13 +49,15 @@ ToDo:
 class unior_state : public driver_device
 {
 public:
-	unior_state(const machine_config &mconfig, device_type type, const char *tag) :
+	unior_state(const machine_config &mconfig, device_type type, const char *tag)
-		driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_pit(*this, "pit"),
+		, m_pit(*this, "pit")
-		m_dma(*this, "dma"),
+		, m_dma(*this, "dma")
-		m_uart(*this, "uart"),
+		, m_uart(*this, "uart")
-		m_palette(*this, "palette")
+		, m_palette(*this, "palette")
+		, m_p_chargen(*this, "chargen")
+		, m_p_vram(*this, "vram")
 	{
 	}
 
@@ -74,8 +76,6 @@ public:
 	DECLARE_READ8_MEMBER(dma_r);
 	I8275_DRAW_CHARACTER_MEMBER(display_pixels);
 
-	uint8_t *m_p_vram;
-	uint8_t *m_p_chargen;
 private:
 	uint8_t m_4c;
 	uint8_t m_4e;
@@ -85,8 +85,9 @@ private:
 	required_device<pit8253_device> m_pit;
 	required_device<i8257_device> m_dma;
 	required_device<i8251_device> m_uart;
-public:
 	required_device<palette_device> m_palette;
+	required_region_ptr<u8> m_p_chargen;
+	required_region_ptr<u8> m_p_vram;
 };
 
 static ADDRESS_MAP_START( unior_mem, AS_PROGRAM, 8, unior_state )
@@ -383,8 +384,6 @@ void unior_state::machine_reset()
 
 void unior_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
-	m_p_vram = memregion("vram")->base();
 }
 
 static MACHINE_CONFIG_START( unior, unior_state )

src/mame/drivers/unistar.cpp

@@ -18,16 +18,19 @@ class unistar_state : public driver_device
 {
 public:
 	unistar_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag) ,
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu") { }
+		, m_maincpu(*this, "maincpu")
+		, m_p_chargen(*this, "chargen")
+		{ }
 
-	virtual void machine_reset() override;
-	virtual void video_start() override;
 	DECLARE_PALETTE_INIT(unistar);
 	uint32_t screen_update_unistar(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	const uint8_t *m_p_chargen;
+
 private:
+	virtual void machine_reset() override;
+	virtual void video_start() override;
 	required_device<cpu_device> m_maincpu;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -51,7 +54,6 @@ INPUT_PORTS_END
 
 void unistar_state::machine_reset()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 PALETTE_INIT_MEMBER( unistar_state, unistar )

src/mame/drivers/univac.cpp

@@ -39,14 +39,15 @@ public:
 		, m_nvram(*this, "nvram")
 		, m_ctc(*this, "ctc")
 		, m_dart(*this, "dart")
+		, m_p_chargen(*this, "chargen")
 	{ }
 
 	DECLARE_READ8_MEMBER(vram_r);
 	DECLARE_WRITE8_MEMBER(vram_w);
 	DECLARE_WRITE8_MEMBER(port43_w);
 	uint32_t screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
 private:
-	const uint8_t *m_p_chargen;
 	bool m_screen_num;
 	uint8_t m_framecnt;
 	virtual void machine_start() override;
@@ -56,6 +57,7 @@ private:
 	required_device<nvram_device> m_nvram;
 	required_device<z80ctc_device> m_ctc;
 	required_device<z80dart_device> m_dart;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -108,7 +110,6 @@ void univac_state::machine_start()
 void univac_state::machine_reset()
 {
 	m_screen_num = 0;
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t univac_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/v6809.cpp

@@ -64,17 +64,19 @@ class v6809_state : public driver_device
 {
 public:
 	v6809_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_video_address(0),
+		, m_video_address(0)
-		m_pia0(*this, "pia0"),
+		, m_pia0(*this, "pia0")
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_crtc(*this, "crtc"),
+		, m_crtc(*this, "crtc")
-		m_fdc(*this, "fdc"),
+		, m_fdc(*this, "fdc")
-		m_floppy0(*this, "fdc:0"),
+		, m_floppy0(*this, "fdc:0")
-		m_speaker(*this, "speaker"),
+		, m_speaker(*this, "speaker")
-		m_acia0(*this, "acia0"),
+		, m_acia0(*this, "acia0")
-		m_acia1(*this, "acia1"),
+		, m_acia1(*this, "acia1")
-		m_palette(*this, "palette")
+		, m_palette(*this, "palette")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -91,11 +93,8 @@ public:
 	MC6845_UPDATE_ROW(crtc_update_row);
 	MC6845_ON_UPDATE_ADDR_CHANGED(crtc_update_addr);
 
-	uint8_t *m_p_videoram;
-	const uint8_t *m_p_chargen;
-	uint16_t m_video_address;
-
 private:
+	uint16_t m_video_address;
 	bool m_speaker_en;
 	uint8_t m_video_index;
 	uint8_t m_term_data;
@@ -108,8 +107,9 @@ private:
 	required_device<speaker_sound_device> m_speaker;
 	required_device<acia6850_device> m_acia0;
 	required_device<acia6850_device> m_acia1;
-public:
 	required_device<palette_device> m_palette;
+	required_region_ptr<u8> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -142,8 +142,6 @@ INPUT_PORTS_END
 
 MACHINE_RESET_MEMBER( v6809_state, v6809)
 {
-	m_p_chargen = memregion("chargen")->base();
-	m_p_videoram = memregion("videoram")->base();
 	m_term_data = 0;
 	m_pia0->cb1_w(1);
 }

src/mame/drivers/vta2000.cpp

@@ -27,18 +27,20 @@ class vta2000_state : public driver_device
 public:
 	vta2000_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag)
-		, m_p_videoram(*this, "videoram")
 		, m_maincpu(*this, "maincpu")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{ }
 
-	const uint8_t *m_p_chargen;
 	uint32_t screen_update_vta2000(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
-	required_shared_ptr<uint8_t> m_p_videoram;
 	DECLARE_PALETTE_INIT(vta2000);
+
 private:
 	virtual void machine_reset() override;
 	virtual void video_start() override;
 	required_device<cpu_device> m_maincpu;
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 static ADDRESS_MAP_START(vta2000_mem, AS_PROGRAM, 8, vta2000_state)
@@ -64,7 +66,6 @@ void vta2000_state::machine_reset()
 
 void vta2000_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t vta2000_state::screen_update_vta2000(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/z1013.cpp

@@ -61,25 +61,29 @@ class z1013_state : public driver_device
 {
 public:
 	z1013_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-	m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-	m_cass(*this, "cassette"),
+		, m_cass(*this, "cassette")
-	m_p_videoram(*this, "videoram"){ }
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
+		{ }
 
-	required_device<cpu_device> m_maincpu;
-	required_device<cassette_image_device> m_cass;
 	DECLARE_WRITE8_MEMBER(z1013_keyboard_w);
 	DECLARE_READ8_MEMBER(port_b_r);
 	DECLARE_WRITE8_MEMBER(port_b_w);
 	DECLARE_READ8_MEMBER(k7659_port_b_r);
-	required_shared_ptr<uint8_t> m_p_videoram;
+	DECLARE_SNAPSHOT_LOAD_MEMBER(z1013);
-	const uint8_t *m_p_chargen;
+	uint32_t screen_update_z1013(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
+private:
 	uint8_t m_keyboard_line;
 	bool m_keyboard_part;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
-	uint32_t screen_update_z1013(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	required_device<cpu_device> m_maincpu;
-	DECLARE_SNAPSHOT_LOAD_MEMBER( z1013 );
+	required_device<cassette_image_device> m_cass;
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -221,7 +225,6 @@ INPUT_PORTS_END
 
 void z1013_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t z1013_state::screen_update_z1013(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/z9001.cpp

@@ -43,32 +43,35 @@ class z9001_state : public driver_device
 {
 public:
 	z9001_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_maincpu(*this, "maincpu"),
+		, m_framecnt(0)
-		m_framecnt(0),
+		, m_maincpu(*this, "maincpu")
-		m_beeper(*this, "beeper"),
+		, m_beeper(*this, "beeper")
-		m_cass(*this, "cassette"),
+		, m_cass(*this, "cassette")
-		m_p_colorram(*this, "colorram"),
+		, m_p_colorram(*this, "colorram")
-		m_p_videoram(*this, "videoram")
+		, m_p_videoram(*this, "videoram")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
-	required_device<cpu_device> m_maincpu;
-	uint8_t m_framecnt;
-	required_device<beep_device> m_beeper;
-	required_device<cassette_image_device> m_cass;
-	required_shared_ptr<uint8_t> m_p_colorram;
-	required_shared_ptr<uint8_t> m_p_videoram;
 	DECLARE_WRITE8_MEMBER(kbd_put);
 	DECLARE_WRITE8_MEMBER(port88_w);
 	DECLARE_WRITE_LINE_MEMBER(cass_w);
-	const uint8_t *m_p_chargen;
+	TIMER_DEVICE_CALLBACK_MEMBER(timer_callback);
+	uint32_t screen_update_z9001(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+
+private:
+	uint8_t m_framecnt;
 	bool m_cassbit;
 	virtual void machine_reset() override;
 	//virtual void machine_start();
 	virtual void video_start() override;
-	uint32_t screen_update_z9001(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
+	required_device<cpu_device> m_maincpu;
-	TIMER_DEVICE_CALLBACK_MEMBER(timer_callback);
+	required_device<beep_device> m_beeper;
+	required_device<cassette_image_device> m_cass;
+	required_shared_ptr<uint8_t> m_p_colorram;
+	required_shared_ptr<uint8_t> m_p_videoram;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 static ADDRESS_MAP_START(z9001_mem, AS_PROGRAM, 8, z9001_state)
@@ -128,7 +131,6 @@ void z9001_state::machine_reset()
 
 void z9001_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 uint32_t z9001_state::screen_update_z9001(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)

src/mame/drivers/zrt80.cpp

@@ -32,13 +32,14 @@ public:
 	};
 
 	zrt80_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag),
+		: driver_device(mconfig, type, tag)
-		m_p_videoram(*this, "videoram"),
+		, m_p_videoram(*this, "videoram")
-		m_maincpu(*this, "maincpu"),
+		, m_maincpu(*this, "maincpu")
-		m_crtc(*this, "crtc"),
+		, m_crtc(*this, "crtc")
-		m_8250(*this, "ins8250"),
+		, m_8250(*this, "ins8250")
-		m_beep(*this, "beeper"),
+		, m_beep(*this, "beeper")
-		m_palette(*this, "palette")
+		, m_palette(*this, "palette")
+		, m_p_chargen(*this, "chargen")
 	{
 	}
 
@@ -47,20 +48,19 @@ public:
 	DECLARE_WRITE8_MEMBER(zrt80_38_w);
 	DECLARE_WRITE8_MEMBER(kbd_put);
 	MC6845_UPDATE_ROW(crtc_update_row);
-	const uint8_t *m_p_chargen;
+
-	required_shared_ptr<uint8_t> m_p_videoram;
-protected:
-	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 private:
+	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 	uint8_t m_term_data;
 	virtual void machine_reset() override;
 	virtual void video_start() override;
+	required_shared_ptr<uint8_t> m_p_videoram;
 	required_device<cpu_device> m_maincpu;
 	required_device<mc6845_device> m_crtc;
 	required_device<ins8250_device> m_8250;
 	required_device<beep_device> m_beep;
-public:
 	required_device<palette_device> m_palette;
+	required_region_ptr<u8> m_p_chargen;
 };
 
 
@@ -209,7 +209,6 @@ void zrt80_state::machine_reset()
 
 void zrt80_state::video_start()
 {
-	m_p_chargen = memregion("chargen")->base();
 }
 
 MC6845_UPDATE_ROW( zrt80_state::crtc_update_row )