diff --git a/src/emu/cpu/m6502/m4510.c b/src/emu/cpu/m6502/m4510.c
index 65c59280b29..2a7eb10ee1e 100644
--- a/src/emu/cpu/m6502/m4510.c
+++ b/src/emu/cpu/m6502/m4510.c
@@ -95,12 +95,12 @@ m4510_device::mi_4510_nd::mi_4510_nd(m4510_device *_base) : mi_4510_normal(_base
 
 UINT8 m4510_device::mi_4510_nd::read_sync(UINT16 adr)
 {
-	return program->read_byte(base->map(adr));
+	return sprogram->read_byte(base->map(adr));
 }
 
 UINT8 m4510_device::mi_4510_nd::read_arg(UINT16 adr)
 {
-	return sprogram->read_byte(base->map(adr));
+	return program->read_byte(base->map(adr));
 }
 
 #include "cpu/m6502/m4510.inc"
diff --git a/src/mame/drivers/mitchell.c b/src/mame/drivers/mitchell.c
index aac45ebe430..432166aa12c 100644
--- a/src/mame/drivers/mitchell.c
+++ b/src/mame/drivers/mitchell.c
@@ -278,12 +278,13 @@ static ADDRESS_MAP_START( mitchell_map, AS_PROGRAM, 8, mitchell_state )
 	AM_RANGE(0xc000, 0xc7ff) AM_READWRITE(pang_paletteram_r,pang_paletteram_w) /* Banked palette RAM */
 	AM_RANGE(0xc800, 0xcfff) AM_READWRITE(pang_colorram_r,pang_colorram_w) AM_SHARE("colorram") /* Attribute RAM */
 	AM_RANGE(0xd000, 0xdfff) AM_READWRITE(pang_videoram_r,pang_videoram_w) AM_SHARE("videoram")/* Banked char / OBJ RAM */
-	AM_RANGE(0xe000, 0xffff) AM_RAM /* Work RAM */
+	AM_RANGE(0xe000, 0xffff) AM_RAM AM_SHARE("ram") /* Work RAM */
 ADDRESS_MAP_END
 
 static ADDRESS_MAP_START( decrypted_opcodes_map, AS_DECRYPTED_OPCODES, 8, mitchell_state )
 	AM_RANGE(0x0000, 0x7fff) AM_ROMBANK("bank0d")
 	AM_RANGE(0x8000, 0xbfff) AM_ROMBANK("bank1d")
+	AM_RANGE(0xe000, 0xffff) AM_RAM AM_SHARE("ram") /* Work RAM */
 ADDRESS_MAP_END
 
 static ADDRESS_MAP_START( mitchell_io_map, AS_IO, 8, mitchell_state )
diff --git a/src/mame/drivers/suna8.c b/src/mame/drivers/suna8.c
index 2761d97955b..6c587027dae 100644
--- a/src/mame/drivers/suna8.c
+++ b/src/mame/drivers/suna8.c
@@ -73,16 +73,15 @@ DRIVER_INIT_MEMBER(suna8_state,hardhead)
 			rom[i] = BITSWAP8(rom[i], 7,6,5,3,4,2,1,0) ^ 0x58;
 	}
 
-	membank("bank0d")->set_base(memregion("maincpu")->base());
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
-	membank("bank1d")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank0d->set_base(memregion("maincpu")->base());
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 /* Non encrypted bootleg */
 DRIVER_INIT_MEMBER(suna8_state,hardhedb)
 {
-	membank("bank0d")->set_base(memregion("maincpu")->base() + 0x48000);
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank0d->set_base(memregion("maincpu")->base() + 0x48000);
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 /***************************************************************************
@@ -138,13 +137,13 @@ DRIVER_INIT_MEMBER(suna8_state, brickzn_common)
 	m_decrypt = brickzn_decrypt();
 
 	// Non-banked opcodes
-	membank("bank0d")->set_base(m_decrypt);
+	m_bank0d->set_base(m_decrypt);
 
 	// Data banks: 00-0f normal data decryption, 10-1f alternate data decryption:
-	membank("bank1")->configure_entries(0, 16*2, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16*2, memregion("maincpu")->base() + 0x10000, 0x4000);
 	// Opcode banks: 00-1f normal opcode decryption:
-	membank("bank1d")->configure_entries(0, 16, m_decrypt + 0x10000, 0x4000);
-	membank("bank1d")->configure_entries(16, 16, m_decrypt + 0x10000, 0x4000);
+	m_bank1d->configure_entries(0, 16, m_decrypt + 0x10000, 0x4000);
+	m_bank1d->configure_entries(16, 16, m_decrypt + 0x10000, 0x4000);
 }
 
 DRIVER_INIT_MEMBER(suna8_state,brickzn)
@@ -203,14 +202,7 @@ DRIVER_INIT_MEMBER(suna8_state,brickznv4)
 
 DRIVER_INIT_MEMBER(suna8_state,brickzn11)
 {
-	// No encryption
-	UINT8   *decrypt =  memregion("maincpu")->base();
-
-	// Data banks: 00-0f normal data decryption, 10-1f alternate data decryption:
-	membank("bank1")->configure_entries(0, 16*2, memregion("maincpu")->base() + 0x10000, 0x4000);
-	// Opcode banks: 00-1f normal opcode decryption:
-	membank("bank1d")->configure_entries(0, 16, decrypt + 0x10000, 0x4000);
-	membank("bank1d")->configure_entries(16, 16, decrypt + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16*2, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 
@@ -226,7 +218,7 @@ DRIVER_INIT_MEMBER(suna8_state,hardhea2)
 	UINT8 x;
 	int i;
 
-	membank("bank0d")->set_base(decrypt);
+	m_bank0d->set_base(decrypt);
 
 	/* Address lines scrambling */
 	memcpy(decrypt, RAM, size);
@@ -295,7 +287,7 @@ rom13:  0?, 1y, 2n, 3n      ?,?,?,? (palettes)
 			RAM[i] = BITSWAP8(RAM[i], 5,6,7,4,3,2,1,0) ^ 0x41;
 	}
 
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 	membank("bank2")->configure_entries(0, 2, auto_alloc_array(machine(), UINT8, 0x2000 * 2), 0x2000);
 }
 
@@ -312,7 +304,7 @@ DRIVER_INIT_MEMBER(suna8_state,starfigh)
 	UINT8 x;
 	int i;
 
-	membank("bank0d")->set_base(decrypt);
+	m_bank0d->set_base(decrypt);
 
 	/* Address lines scrambling */
 	memcpy(decrypt, RAM, size);
@@ -381,7 +373,7 @@ DRIVER_INIT_MEMBER(suna8_state,starfigh)
 	decrypt[0x2696] = 0xc9; // work ram writes disable, corrupt next routine
 	decrypt[0x4e9a] = 0x00; // work ram writes disable, flip background sprite
 
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 
@@ -397,7 +389,7 @@ DRIVER_INIT_MEMBER(suna8_state,sparkman)
 	UINT8 x;
 	int i;
 
-	membank("bank0d")->set_base(decrypt);
+	m_bank0d->set_base(decrypt);
 
 	/* Address lines scrambling */
 	memcpy(decrypt, RAM, size);
@@ -464,7 +456,7 @@ DRIVER_INIT_MEMBER(suna8_state,sparkman)
 	decrypt[0x1ac4] = 0x00;
 	decrypt[0x1ac5] = 0x00;
 
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 /***************************************************************************
@@ -535,8 +527,7 @@ WRITE8_MEMBER(suna8_state::hardhead_bankswitch_w)
 	int bank = data & 0x0f;
 
 	if (data & ~0xef)   logerror("CPU #0 - PC %04X: unknown bank bits: %02X\n",space.device().safe_pc(),data);
-	membank("bank1")->set_entry(bank);
-	membank("bank1d")->set_entry(bank);
+	m_bank1->set_entry(bank);
 }
 
 
@@ -569,11 +560,6 @@ static ADDRESS_MAP_START( hardhead_map, AS_PROGRAM, 8, suna8_state )
 	AM_RANGE(0xe000, 0xffff) AM_RAM_WRITE(suna8_spriteram_w) AM_SHARE("spriteram")  // Sprites
 ADDRESS_MAP_END
 
-static ADDRESS_MAP_START( decrypted_opcodes_map, AS_DECRYPTED_OPCODES, 8, suna8_state )
-	AM_RANGE(0x0000, 0x7fff) AM_ROMBANK("bank0d")
-	AM_RANGE(0x8000, 0xbfff) AM_ROMBANK("bank1d")
-ADDRESS_MAP_END
-
 static ADDRESS_MAP_START( hardhead_io_map, AS_IO, 8, suna8_state )
 	ADDRESS_MAP_GLOBAL_MASK(0xff)
 	AM_RANGE(0x00, 0x00) AM_READNOP // ? IRQ Ack
@@ -597,8 +583,7 @@ WRITE8_MEMBER(suna8_state::rranger_bankswitch_w)
 
 	if (data & ~0xf7)   logerror("CPU #0 - PC %04X: unknown bank bits: %02X\n",space.device().safe_pc(),data);
 
-	membank("bank1")->set_entry(bank);
-	membank("bank1d")->set_entry(bank);
+	m_bank1->set_entry(bank);
 
 	flip_screen_set(data & 0x20);
 	coin_lockout_w ( machine(), 0,  data & 0x40);
@@ -697,8 +682,9 @@ WRITE8_MEMBER(suna8_state::brickzn_rombank_w)
 
 	if (data & ~0x0f)   logerror("CPU #0 - PC %04X: unknown rom bank bits: %02X\n",space.device().safe_pc(),data);
 
-	membank("bank1")->set_entry(bank + (membank("bank1")->entry() & 0x10));
-	membank("bank1d")->set_entry(membank("bank1")->entry());
+	m_bank1->set_entry(bank + (m_bank1->entry() & 0x10));
+	if(m_bank1d)
+		m_bank1d->set_entry(m_bank1->entry());
 
 	m_rombank = data;
 }
@@ -816,11 +802,11 @@ WRITE8_MEMBER(suna8_state::brickzn_multi_w)
 
 		if (m_prot_opcode_toggle == 0)
 		{
-			membank("bank0d")->set_base(m_decrypt);
+			m_bank0d->set_base(m_decrypt);
 		}
 		else
 		{
-			membank("bank0d")->set_base(memregion("maincpu")->base());
+			m_bank0d->set_base(memregion("maincpu")->base());
 		}
 	}
 }
@@ -840,8 +826,9 @@ WRITE8_MEMBER(suna8_state::brickzn_prot2_w)
 	m_remap_sound = ((m_prot2 ^ data) == 0xf8) ? 1 : 0;
 
 	// Select alternate data decryption, see code at 787e:
-	membank("bank1")->set_entry((membank("bank1")->entry() & 0x0f) + ((m_prot2 == (data | 0xdc)) ? 0x10 : 0));
-	membank("bank1d")->set_entry(membank("bank1")->entry());
+	m_bank1->set_entry((m_bank1->entry() & 0x0f) + ((m_prot2 == (data | 0xdc)) ? 0x10 : 0));
+	if(m_bank1d)
+		m_bank1d->set_entry(m_bank1->entry());
 
 	m_prot2_prev = m_prot2;
 	m_prot2 = data;
@@ -888,6 +875,11 @@ static ADDRESS_MAP_START( brickzn_map, AS_PROGRAM, 8, suna8_state )
 	AM_RANGE(0xe000, 0xffff) AM_READWRITE(suna8_banked_spriteram_r, suna8_banked_spriteram_w)   // Sprites (Banked)
 ADDRESS_MAP_END
 
+static ADDRESS_MAP_START( decrypted_opcodes_map, AS_DECRYPTED_OPCODES, 8, suna8_state )
+	AM_RANGE(0x0000, 0x7fff) AM_ROMBANK("bank0d")
+	AM_RANGE(0x8000, 0xbfff) AM_ROMBANK("bank1d")
+ADDRESS_MAP_END
+
 static ADDRESS_MAP_START( brickzn_io_map, AS_IO, 8, suna8_state )
 	AM_RANGE(0x0000, 0x0000) AM_WRITE(brickzn_disab_palram_w    )   // Disable Palette RAM
 	AM_RANGE(0x00a1, 0x00a1) AM_WRITE(brickzn_enab_palram_w     )   // Enable Palette RAM
@@ -943,8 +935,7 @@ WRITE8_MEMBER(suna8_state::hardhea2_rombank_w)
 
 	if (data & ~0x0f)   logerror("CPU #0 - PC %04X: unknown rom bank bits: %02X\n",space.device().safe_pc(),data);
 
-	membank("bank1")->set_entry(bank);
-	membank("bank1d")->set_entry(bank);
+	m_bank1->set_entry(bank);
 
 	m_rombank = data;
 }
@@ -1083,8 +1074,7 @@ WRITE8_MEMBER(suna8_state::starfigh_leds_w)
 
 	int bank = m_rombank_latch & 0x0f;
 
-	membank("bank1")->set_entry(bank);
-	membank("bank1d")->set_entry(bank);
+	m_bank1->set_entry(bank);
 
 	m_rombank = m_rombank_latch;
 	logerror("CPU #0 - PC %04X: rom bank = %02X\n",space.device().safe_pc(), m_rombank);
@@ -1197,8 +1187,7 @@ WRITE8_MEMBER(suna8_state::sparkman_rombank_w)
 
 	int bank = m_rombank_latch & 0x0f;
 
-	membank("bank1")->set_entry(bank);
-	membank("bank1d")->set_entry(bank);
+	m_bank1->set_entry(bank);
 
 	m_rombank = m_rombank_latch;
 	logerror("CPU #0 - PC %04X: rom bank = %02X\n",space.device().safe_pc(), m_rombank);
@@ -1929,7 +1918,7 @@ static MACHINE_CONFIG_START( rranger, suna8_state )
 	MCFG_CPU_ADD("maincpu", Z80, SUNA8_MASTER_CLOCK / 4)                    /* ? */
 	MCFG_CPU_PROGRAM_MAP(rranger_map)
 	MCFG_CPU_IO_MAP(rranger_io_map)
-	MCFG_CPU_DECRYPTED_OPCODES_MAP(decrypted_opcodes_map)
+//	MCFG_CPU_DECRYPTED_OPCODES_MAP(decrypted_opcodes_map)
 	MCFG_CPU_VBLANK_INT_DRIVER("screen", suna8_state,  irq0_line_hold)  /* IRQ & NMI ! */
 
 	MCFG_CPU_ADD("audiocpu", Z80, SUNA8_MASTER_CLOCK / 8)   /* verified on pcb */
@@ -1981,8 +1970,9 @@ MACHINE_RESET_MEMBER(suna8_state,brickzn)
 	m_protection_val = m_prot2 = m_prot2_prev = 0xff;
 	m_paletteram_enab = 1;  // for brickzn11
 	m_remap_sound = 0;
-	membank("bank1")->set_entry(0);
-	membank("bank1d")->set_entry(0);
+	m_bank1->set_entry(0);
+	if(m_bank1d)
+		m_bank1d->set_entry(0);
 }
 
 static MACHINE_CONFIG_START( brickzn11, suna8_state )
@@ -1990,7 +1980,6 @@ static MACHINE_CONFIG_START( brickzn11, suna8_state )
 	/* basic machine hardware */
 	MCFG_CPU_ADD("maincpu", Z80, SUNA8_MASTER_CLOCK / 4)        /* SUNA PROTECTION BLOCK */
 	MCFG_CPU_PROGRAM_MAP(brickzn11_map)
-	MCFG_CPU_DECRYPTED_OPCODES_MAP(decrypted_opcodes_map)
 	MCFG_CPU_VBLANK_INT_DRIVER("screen", suna8_state,  irq0_line_hold)  // nmi breaks ramtest but is needed!
 
 	MCFG_CPU_ADD("audiocpu", Z80, SUNA8_MASTER_CLOCK / 4)   /* Z0840006PSC - 6MHz (measured) */
@@ -2045,6 +2034,7 @@ static MACHINE_CONFIG_DERIVED( brickzn, brickzn11 )
 	MCFG_CPU_MODIFY("maincpu")
 	MCFG_CPU_PROGRAM_MAP(brickzn_map)
 	MCFG_CPU_IO_MAP(brickzn_io_map)
+	MCFG_CPU_DECRYPTED_OPCODES_MAP(decrypted_opcodes_map)
 MACHINE_CONFIG_END
 
 
@@ -2928,7 +2918,7 @@ ROM_END
 
 DRIVER_INIT_MEMBER(suna8_state,suna8)
 {
-	membank("bank1")->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
+	m_bank1->configure_entries(0, 16, memregion("maincpu")->base() + 0x10000, 0x4000);
 }
 
 GAME( 1988, sranger,   0,        rranger,  rranger,  suna8_state, suna8,     ROT0,  "SunA",                       "Super Ranger (v2.0)",                0 )
diff --git a/src/mame/includes/suna8.h b/src/mame/includes/suna8.h
index 8b57fd158e3..379250fae09 100644
--- a/src/mame/includes/suna8.h
+++ b/src/mame/includes/suna8.h
@@ -19,7 +19,9 @@ public:
 		m_gfxdecode(*this, "gfxdecode"),
 		m_screen(*this, "screen"),
 		m_palette(*this, "palette"),
-
+		m_bank0d(*this, "bank0d"),
+		m_bank1(*this, "bank1"),
+		m_bank1d(*this, "bank1d"),
 		m_prot_opcode_toggle(0),
 		m_remap_sound(0)
 		{ }
@@ -34,6 +36,9 @@ public:
 	required_device<gfxdecode_device> m_gfxdecode;
 	required_device<screen_device> m_screen;
 	required_device<palette_device> m_palette;
+	optional_memory_bank m_bank0d;
+	required_memory_bank m_bank1;
+	optional_memory_bank m_bank1d;
 
 	UINT8 m_rombank;
 	UINT8 m_rombank_latch;