(MESS) astrocade: converted the expansion bus to be a slot

device, and converted RAM expansions to be slot cards. As a
result you now specify the expansion you want by using e.g.
    mess astrocde -exp blue_ram_32k
or the Slot Devices menu of the internal UI, instead of using the
DipSwitches menu. Check the -lslot output for a list of available
expansions. [Fabio Priuli]

src/emu/bus/astrocde/exp.c

@@ -0,0 +1,82 @@
+// license:BSD-3-Clause
+// copyright-holders:etabeta
+/***********************************************************************************************************
+
+    Bally Astrocade Expansion port
+
+ ***********************************************************************************************************/
+
+
+#include "emu.h"
+#include "exp.h"
+
+//**************************************************************************
+//  GLOBAL VARIABLES
+//**************************************************************************
+
+const device_type ASTROCADE_EXP_SLOT = &device_creator<astrocade_exp_device>;
+
+
+device_astrocade_card_interface::device_astrocade_card_interface(const machine_config &mconfig, device_t &device)
+	: device_slot_card_interface(mconfig, device)
+{
+}
+
+
+device_astrocade_card_interface::~device_astrocade_card_interface()
+{
+}
+
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+//  astrocade_exp_device - constructor
+//-------------------------------------------------
+astrocade_exp_device::astrocade_exp_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+						device_t(mconfig, ASTROCADE_EXP_SLOT, "Bally Astrocade expansion", tag, owner, clock, "astrocde_exp", __FILE__),
+						device_slot_interface(mconfig, *this)
+{
+}
+
+
+//-------------------------------------------------
+//  astrocade_exp_device - destructor
+//-------------------------------------------------
+
+astrocade_exp_device::~astrocade_exp_device()
+{
+}
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void astrocade_exp_device::device_start()
+{
+	m_card = dynamic_cast<device_astrocade_card_interface *>(get_card_device());
+}
+
+/*-------------------------------------------------
+ read
+ -------------------------------------------------*/
+
+READ8_MEMBER(astrocade_exp_device::read)
+{
+	if (m_card)
+		return m_card->read(space, offset);
+	else
+		return 0xff;
+}
+
+/*-------------------------------------------------
+ write
+ -------------------------------------------------*/
+
+WRITE8_MEMBER(astrocade_exp_device::write)
+{
+	if (m_card)
+		m_card->write(space, offset, data);
+}

src/emu/bus/astrocde/exp.h

@@ -0,0 +1,55 @@
+// license:BSD-3-Clause
+// copyright-holders:etabeta
+#ifndef __ASTROCADE_EXP_H
+#define __ASTROCADE_EXP_H
+
+// ======================> device_astrocade_card_interface
+
+class device_astrocade_card_interface : public device_slot_card_interface
+{
+public:
+	// construction/destruction
+	device_astrocade_card_interface(const machine_config &mconfig, device_t &device);
+	virtual ~device_astrocade_card_interface();
+
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read) { return 0; }
+	virtual DECLARE_WRITE8_MEMBER(write) {}
+
+protected:
+};
+
+
+// ======================> astrocade_exp_device
+
+class astrocade_exp_device : public device_t,
+								public device_slot_interface
+{
+public:
+	// construction/destruction
+	astrocade_exp_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	virtual ~astrocade_exp_device();
+
+	// device-level overrides
+	virtual void device_start();
+
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read);
+	virtual DECLARE_WRITE8_MEMBER(write);
+
+protected:
+
+	device_astrocade_card_interface* m_card;
+};
+
+
+
+// device type definition
+extern const device_type ASTROCADE_EXP_SLOT;
+
+
+#define MCFG_ASTROCADE_EXPANSION_SLOT_ADD(_tag, _slot_intf, _def_slot) \
+	MCFG_DEVICE_ADD(_tag, ASTROCADE_EXP_SLOT, 0) \
+	MCFG_DEVICE_SLOT_INTERFACE(_slot_intf, _def_slot, false)
+
+#endif

src/emu/bus/astrocde/ram.c

@@ -0,0 +1,213 @@
+// license:BSD-3-Clause
+// copyright-holders:etabeta
+/***********************************************************************************************************
+
+
+  Bally Astrocade RAM expansion emulation
+
+      RAM Expansions (info below courtesy of Paul Thacker)
+
+      Several third party RAM expansions have been made for the Astrocade.  These
+      allow access to various ranges of the expansion memory ($5000 to $FFFF).
+      A RAM expansion is required to use extended BASIC programs like Blue RAM BASIC
+      and VIPERSoft BASIC.  All of the expansions also have a RAM protect switch, which
+      can be flipped at any time to make the RAM act like ROM.  Extended BASIC
+      programs need access to the RAM and won't work with RAM protect enabled, but
+      this can be useful with Bally and Astrocade BASIC.  They also have a range switch
+      (not implemented).  The default position is 6K, but it can be switched to
+      2K.  This means that the expanded memory starting at $6000 will instead be
+      mapped to the cartridge memory starting at $2000.  So it would be possible to
+      load a cartridge program from tape into the expansion memory, then flip the range
+      switch and run it as a cartridge.  This is useful for cartridge development.
+     
+      Blue RAM -- available in 4K, 16K, and 32K.  These also use an INS8154 chip,
+      (not yet implemented) which has an additional $80 bytes of RAM mapped
+      immediately after the end of the expansion address space.  This memory
+      can't be write protected.  The INS8154 has I/O features needed for loading
+      tape programs into Blue RAM BASIC, as well as running the Blue RAM Utility cart.
+      4K:  $6000 to $6FFF (can't run VIPERSoft BASIC, because this program needs memory
+      past this range)
+      16K:  $6000 to $9FFF
+      32K:  $6000 to $DFFF
+     
+      VIPER System 1 -- This is available in 16K only.  It also includes a keyboard (not implemented).
+      16K:  $6000 to $9FFF
+     
+      Lil' WHITE RAM -- This is available in 32K only.  Attempts to read and write
+      to memory outside of its address range ($D000 to $FFFF) are mapped to the expansion
+      memory $5000 to $7FFF.  The current implementation won't allow the shadow RAM area
+      to be accessed when RAM protect is on, but there is no known software that will
+      access the upper range of the expansion RAM when RAM protect is enabled.
+      32K:  $5000 to $CFFF
+     
+      R&L 64K RAM Board -- This is a highly configurable kit.  RAM can be installed in
+      2K increments.  So, the entire 44K expansion memory can be filled.  It is also
+      possible to override the rest of the memory map with RAM (not implemented).
+      There are 32 switches allowing users to activate and deactivate each 2K block (not implemented).
+      RAM write protection can be implemented in three ranges through jumpers or by
+      installing switches.  The ranges are $0000 to $0FFF (first 4K), $0000 to $3FFF (first 16K),
+      and $0000 to $FFFF (all 64K).  The current implementation is for 44K expansion memory mapped from
+      $5000 to $FFFF, with only a single write protect covering this entire range.
+ 
+ ***********************************************************************************************************/
+
+
+#include "emu.h"
+#include "ram.h"
+
+
+//-------------------------------------------------
+//  astrocade_rom_device - constructor
+//-------------------------------------------------
+
+const device_type ASTROCADE_BLUERAM_4K  = &device_creator<astrocade_blueram_4k_device>;
+const device_type ASTROCADE_BLUERAM_16K = &device_creator<astrocade_blueram_16k_device>;
+const device_type ASTROCADE_BLUERAM_32K = &device_creator<astrocade_blueram_32k_device>;
+const device_type ASTROCADE_VIPER_SYS1  = &device_creator<astrocade_viper_sys1_device>;
+const device_type ASTROCADE_WHITERAM    = &device_creator<astrocade_whiteram_device>;
+const device_type ASTROCADE_RL64RAM     = &device_creator<astrocade_rl64ram_device>;
+
+
+astrocade_blueram_4k_device::astrocade_blueram_4k_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source)
+					: device_t(mconfig, type, name, tag, owner, clock, shortname, source),
+						device_astrocade_card_interface(mconfig, *this),
+						m_write_prot(*this, "RAM_PROTECT")
+{
+}
+
+astrocade_blueram_4k_device::astrocade_blueram_4k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: device_t(mconfig, ASTROCADE_BLUERAM_4K, "Bally Astrocade Blue RAM 4K", tag, owner, clock, "astrocade_br4", __FILE__),
+						device_astrocade_card_interface(mconfig, *this),
+						m_write_prot(*this, "RAM_PROTECT")
+{
+}
+
+astrocade_blueram_16k_device::astrocade_blueram_16k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: astrocade_blueram_4k_device(mconfig, ASTROCADE_BLUERAM_16K, "Bally Astrocade Blue RAM 16K", tag, owner, clock, "astrocade_br16", __FILE__)
+{
+}
+
+astrocade_blueram_32k_device::astrocade_blueram_32k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: astrocade_blueram_4k_device(mconfig, ASTROCADE_BLUERAM_32K, "Bally Astrocade Blue RAM 32K", tag, owner, clock, "astrocade_br32", __FILE__)
+{
+}
+
+astrocade_viper_sys1_device::astrocade_viper_sys1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: device_t(mconfig, ASTROCADE_VIPER_SYS1, "Bally Astrocade Viper System 1", tag, owner, clock, "astrocade_vs1", __FILE__),
+						device_astrocade_card_interface(mconfig, *this),
+						m_write_prot(*this, "RAM_PROTECT")
+{
+}
+
+astrocade_whiteram_device::astrocade_whiteram_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: device_t(mconfig, ASTROCADE_WHITERAM, "Bally Astrocade Lil' White RAM 32K", tag, owner, clock, "astrocade_lwr", __FILE__),
+						device_astrocade_card_interface(mconfig, *this),
+						m_write_prot(*this, "RAM_PROTECT")
+{
+}
+
+astrocade_rl64ram_device::astrocade_rl64ram_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+					: device_t(mconfig, ASTROCADE_RL64RAM, "Bally Astrocade R&L RAM 64K", tag, owner, clock, "astrocade_rl64", __FILE__),
+						device_astrocade_card_interface(mconfig, *this),
+						m_write_prot(*this, "RAM_PROTECT")
+{
+}
+
+
+//-------------------------------------------------
+//  RAM Write protect switch
+//-------------------------------------------------
+
+static INPUT_PORTS_START( exp_switches )
+	PORT_START("RAM_PROTECT")
+	PORT_CONFNAME( 0x01, 0x00, "Write Protect RAM")
+	PORT_CONFSETTING( 0x00, DEF_STR(Off))
+	PORT_CONFSETTING( 0x01, DEF_STR(On))
+INPUT_PORTS_END
+
+
+ioport_constructor astrocade_blueram_4k_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( exp_switches );
+}
+
+ioport_constructor astrocade_viper_sys1_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( exp_switches );
+}
+
+ioport_constructor astrocade_whiteram_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( exp_switches );
+}
+
+ioport_constructor astrocade_rl64ram_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( exp_switches );
+}
+
+/*-------------------------------------------------
+ specific handlers
+ -------------------------------------------------*/
+
+// Blue RAM expansions have RAM starting at 0x6000, up to the RAM size
+READ8_MEMBER(astrocade_blueram_4k_device::read)
+{
+	if (offset >= 0x1000 && offset < 0x1000 + m_ram.bytes())
+		return m_ram[offset - 0x1000];
+	else
+		return 0;
+}
+
+WRITE8_MEMBER(astrocade_blueram_4k_device::write)
+{
+	if (offset >= 0x1000 && offset < 0x1000 + m_ram.bytes() && !m_write_prot->read())
+		m_ram[offset - 0x1000] = data;
+}
+
+
+
+// Viper System 1 expansion has RAM in 0x6000-0x9fff
+READ8_MEMBER(astrocade_viper_sys1_device::read)
+{
+	if (offset >= 0x1000 && offset < 0xa000)
+		return m_ram[offset - 0x1000];
+	else
+		return 0;
+}
+
+WRITE8_MEMBER(astrocade_viper_sys1_device::write)
+{
+	if (offset >= 0x1000 && offset < 0xa000 && !m_write_prot->read())
+		m_ram[offset - 0x1000] = data;
+}
+
+
+
+// Lil' WHITE RAM expansion has RAM in 0x5000-0xcfff + a mirror of the first 0x3000 bytes up to 0xffff
+READ8_MEMBER(astrocade_whiteram_device::read)
+{
+	return m_ram[offset % 0x8000];
+}
+
+WRITE8_MEMBER(astrocade_whiteram_device::write)
+{
+	if (!m_write_prot->read())
+		m_ram[offset % 0x8000] = data;
+}
+
+
+
+// R&L 64K RAM Board (44KB installed) has RAM in 0x5000-0xffff
+READ8_MEMBER(astrocade_rl64ram_device::read)
+{
+	return m_ram[offset];
+}
+
+WRITE8_MEMBER(astrocade_rl64ram_device::write)
+{
+	if (!m_write_prot->read())
+		m_ram[offset] = data;
+}
+
+

src/emu/bus/astrocde/ram.h

@@ -0,0 +1,135 @@
+// license:BSD-3-Clause
+// copyright-holders:etabeta
+#ifndef __ASTROCADE_RAM_H
+#define __ASTROCADE_RAM_H
+
+#include "exp.h"
+
+
+// ======================> astrocade_blueram_4k_device
+
+class astrocade_blueram_4k_device : public device_t,
+								public device_astrocade_card_interface
+{
+public:
+	// construction/destruction
+	astrocade_blueram_4k_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source);
+	astrocade_blueram_4k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+
+	// device-level overrides
+	virtual void device_start() { m_ram.resize(0x1000); save_item(NAME(m_ram)); }
+	virtual void device_reset() {}
+	virtual ioport_constructor device_input_ports() const;
+
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read);
+	virtual DECLARE_WRITE8_MEMBER(write);
+
+protected:
+	dynamic_buffer m_ram;
+	required_ioport m_write_prot;
+};
+
+// ======================> astrocade_blueram_16k_device
+
+class astrocade_blueram_16k_device : public astrocade_blueram_4k_device
+{
+public:
+	// construction/destruction
+	astrocade_blueram_16k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	
+	virtual void device_start() { m_ram.resize(0x4000); save_item(NAME(m_ram)); }
+};
+
+// ======================> astrocade_blueram_32k_device
+
+class astrocade_blueram_32k_device : public astrocade_blueram_4k_device
+{
+public:
+	// construction/destruction
+	astrocade_blueram_32k_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	
+	virtual void device_start() { m_ram.resize(0x8000); save_item(NAME(m_ram)); }
+};
+
+// ======================> astrocade_viper_sys1_device
+
+class astrocade_viper_sys1_device : public device_t,
+								public device_astrocade_card_interface
+{
+public:
+	// construction/destruction
+	astrocade_viper_sys1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	
+	// device-level overrides
+	virtual void device_start() { m_ram.resize(0x4000); save_item(NAME(m_ram)); }
+	virtual void device_reset() {}
+	virtual ioport_constructor device_input_ports() const;
+
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read);
+	virtual DECLARE_WRITE8_MEMBER(write);
+	
+private:
+	dynamic_buffer m_ram;
+	required_ioport m_write_prot;
+};
+
+// ======================> astrocade_whiteram_device
+
+class astrocade_whiteram_device : public device_t,
+								public device_astrocade_card_interface
+{
+public:
+	// construction/destruction
+	astrocade_whiteram_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	
+	// device-level overrides
+	virtual void device_start() { m_ram.resize(0x8000); save_item(NAME(m_ram)); }
+	virtual void device_reset() {}
+	virtual ioport_constructor device_input_ports() const;
+	
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read);
+	virtual DECLARE_WRITE8_MEMBER(write);
+	
+private:
+	dynamic_buffer m_ram;
+	required_ioport m_write_prot;
+};
+
+// ======================> astrocade_rl64ram_device
+
+class astrocade_rl64ram_device : public device_t,
+							public device_astrocade_card_interface
+{
+public:
+	// construction/destruction
+	astrocade_rl64ram_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+	
+	// device-level overrides
+	virtual void device_start() { m_ram.resize(0xb000); save_item(NAME(m_ram)); }
+	virtual void device_reset() {}
+	virtual ioport_constructor device_input_ports() const;
+	
+	// reading and writing
+	virtual DECLARE_READ8_MEMBER(read);
+	virtual DECLARE_WRITE8_MEMBER(write);
+	
+private:
+	dynamic_buffer m_ram;
+	required_ioport m_write_prot;
+};
+
+
+
+// device type definition
+extern const device_type ASTROCADE_BLUERAM_4K;
+extern const device_type ASTROCADE_BLUERAM_16K;
+extern const device_type ASTROCADE_BLUERAM_32K;
+extern const device_type ASTROCADE_VIPER_SYS1;
+extern const device_type ASTROCADE_WHITERAM;
+extern const device_type ASTROCADE_RL64RAM;
+
+
+#endif

src/emu/bus/bus.mak

@@ -129,6 +129,8 @@ ifneq ($(filter ASTROCADE,$(BUSES)),)
 OBJDIRS += $(BUSOBJ)/astrocde
 BUSOBJS += $(BUSOBJ)/astrocde/slot.o
 BUSOBJS += $(BUSOBJ)/astrocde/rom.o
+BUSOBJS += $(BUSOBJ)/astrocde/exp.o
+BUSOBJS += $(BUSOBJ)/astrocde/ram.o
 endif
 
 

src/mess/drivers/astrocde.c

@@ -14,6 +14,8 @@
 #include "sound/astrocde.h"
 #include "bus/astrocde/slot.h"
 #include "bus/astrocde/rom.h"
+#include "bus/astrocde/exp.h"
+#include "bus/astrocde/ram.h"
 
 class astrocde_mess_state : public astrocde_state
 {
@@ -24,13 +26,10 @@ public:
 		{ }
 
 	required_device<astrocade_cart_slot_device> m_cart;
-	void get_ram_expansion_settings(int &ram_expansion_installed, int &write_protect_on, int &expansion_ram_start, int &expansion_ram_end, int &shadow_ram_end);
 	DECLARE_MACHINE_START(astrocde);
-	DECLARE_MACHINE_RESET(astrocde);
-	DECLARE_INPUT_CHANGED_MEMBER(set_write_protect);
 };
 
-/*************************************
+/*********************************************************************************
  *
  *  Memory maps
  *
@@ -42,58 +41,13 @@ public:
  * by an extended BASIC program.  Bally and Astrocade BASIC can access from
  * $5000 to $7FFF if available.
  *
- *  RAM Expansions
+ *********************************************************************************/
- *
- * Several third party RAM expansions have been made for the Astrocade.  These
- * allow access to various ranges of the expansion memory ($5000 to $FFFF).
- * A RAM expansion is required to use extended BASIC programs like Blue RAM BASIC
- * and VIPERSoft BASIC.  All of the expansions also have a RAM protect switch, which
- * can be flipped at any time to make the RAM act like ROM.  Extended BASIC
- * programs need access to the RAM and won't work with RAM protect enabled, but
- * this can be useful with Bally and Astrocade BASIC.  They also have a range switch
- * (not implemented).  The default position is 6K, but it can be switched to
- * 2K.  This means that the expanded memory starting at $6000 will instead be
- * mapped to the cartridge memory starting at $2000.  So it would be possible to
- * load a cartridge program from tape into the expansion memory, then flip the range
- * switch and run it as a cartridge.  This is useful for cartridge development.
- *
- * NOTE:  If you have any trouble running cartridges with a RAM expansion installed, hit reset.
- *
- * Blue RAM -- available in 4K, 16K, and 32K.  These also use an INS8154 chip,
- * (not yet implemented) which has an additional $80 bytes of RAM mapped
- * immediately after the end of the expansion address space.  This memory
- * can't be write protected.  The INS8154 has I/O features needed for loading
- * tape programs into Blue RAM BASIC, as well as running the Blue RAM Utility cart.
- * 4K:  $6000 to $6FFF (can't run VIPERSoft BASIC, because this program needs memory
- * past this range)
- * 16K:  $6000 to $9FFF
- * 32K:  $6000 to $DFFF
- *
- * VIPER System 1 -- This is available in 16K only.  It also includes a keyboard (not implemented).
- * 16K:  $6000 to $9FFF
- *
- * Lil' WHITE RAM -- This is available in 32K only.  Attempts to read and write
- * to memory outside of its address range ($D000 to $FFFF) are mapped to the expansion
- * memory $5000 to $7FFF.  The current implementation won't allow the shadow RAM area
- * to be accessed when RAM protect is on, but there is no known software that will
- * access the upper range of the expansion RAM when RAM protect is enabled.
- * 32K:  $5000 to $CFFF
- *
- * R&L 64K RAM Board -- This is a highly configurable kit.  RAM can be installed in
- * 2K increments.  So, the entire 44K expansion memory can be filled.  It is also
- * possible to override the rest of the memory map with RAM (not implemented).
- * There are 32 switches allowing users to activate and deactivate each 2K block (not implemented).
- * RAM write protection can be implemented in three ranges through jumpers or by
- * installing switches.  The ranges are $0000 to $0FFF (first 4K), $0000 to $3FFF (first 16K),
- * and $0000 to $FFFF (all 64K).  The current implementation is for 44K expansion memory mapped from
- * $5000 to $FFFF, with only a single write protect covering this entire range.
- *
- *************************************/
 
 static ADDRESS_MAP_START( astrocade_mem, AS_PROGRAM, 8, astrocde_mess_state )
 	AM_RANGE(0x0000, 0x0fff) AM_ROM AM_WRITE(astrocade_funcgen_w)
 	AM_RANGE(0x1000, 0x3fff) AM_ROM /* Star Fortress writes in here?? */
 	AM_RANGE(0x4000, 0x4fff) AM_RAM AM_SHARE("videoram") /* ASG */
+	AM_RANGE(0x5000, 0xffff) AM_DEVREADWRITE("exp", astrocade_exp_device, read, write)
 ADDRESS_MAP_END
 
 
@@ -101,29 +55,6 @@ static ADDRESS_MAP_START( astrocade_io, AS_IO, 8, astrocde_mess_state )
 	AM_RANGE(0x00, 0x1f) AM_MIRROR(0xff00) AM_MASK(0xffff) AM_READWRITE(astrocade_data_chip_register_r, astrocade_data_chip_register_w)
 ADDRESS_MAP_END
 
-INPUT_CHANGED_MEMBER(astrocde_mess_state::set_write_protect)  // run when RAM expansion write protect switch is changed
-{
-	int ram_expansion_installed = 0, write_protect_on = 0, expansion_ram_start = 0, expansion_ram_end = 0, shadow_ram_end = 0;
-	address_space &space = m_maincpu->space(AS_PROGRAM);
-	UINT8 *expram = machine().device<ram_device>("ram_tag")->pointer();
-
-	get_ram_expansion_settings(ram_expansion_installed, write_protect_on, expansion_ram_start, expansion_ram_end, shadow_ram_end);  // passing by reference
-
-	if (ram_expansion_installed == 1)
-	{
-		if (write_protect_on == 0)  // write protect off, so install memory normally
-		{
-			space.install_ram(expansion_ram_start, expansion_ram_end, expram);
-			if (shadow_ram_end > expansion_ram_end)
-				space.install_ram(expansion_ram_end + 1, shadow_ram_end, expram);
-		}
-		else  // write protect on, so make memory read only
-		{
-			space.nop_write(expansion_ram_start, expansion_ram_end);
-		}
-	}
-}
-
 /*************************************
  *
  *  Input ports
@@ -227,21 +158,6 @@ static INPUT_PORTS_START( astrocde )
 
 	PORT_START("P4_KNOB")
 	PORT_BIT(0xff, 0x00, IPT_PADDLE) PORT_INVERT PORT_SENSITIVITY(85) PORT_KEYDELTA(10) PORT_CENTERDELTA(0) PORT_MINMAX(0,255) PORT_CODE_DEC(KEYCODE_Y) PORT_CODE_INC(KEYCODE_U) PORT_PLAYER(4)
-
-	PORT_START("CFG")   /* machine config */
-	PORT_DIPNAME( 0x3f, 0x00, "RAM Expansion")
-	PORT_DIPSETTING(    0x00, "No RAM Expansion")
-	PORT_DIPSETTING(    0x01, "16KB Viper System 1 RAM Expansion")
-	PORT_DIPSETTING(    0x02, "32KB Lil' WHITE RAM Expansion")
-	PORT_DIPSETTING(    0x04, "R&L 64K RAM Board (44K installed)")
-	PORT_DIPSETTING(    0x08, "4KB Blue RAM Expansion")
-	PORT_DIPSETTING(    0x10, "16KB Blue RAM Expansion")
-	PORT_DIPSETTING(    0x20, "32KB Blue RAM Expansion")
-
-	PORT_START("PROTECT")  /* Write protect RAM */
-	PORT_DIPNAME( 0x01, 0x00, "Write Protect RAM") PORT_CHANGED_MEMBER(DEVICE_SELF, astrocde_mess_state, set_write_protect, 0)
-	PORT_DIPSETTING( 0x00, "Write Protect Off")
-	PORT_DIPSETTING( 0x01, "Write Protect On")
 INPUT_PORTS_END
 
 
@@ -257,6 +173,15 @@ static SLOT_INTERFACE_START(astrocade_cart)
 	SLOT_INTERFACE_INTERNAL("rom_512k",  ASTROCADE_ROM_512K)
 SLOT_INTERFACE_END
 
+static SLOT_INTERFACE_START(astrocade_exp)
+	SLOT_INTERFACE("blue_ram_4k",   ASTROCADE_BLUERAM_4K)
+	SLOT_INTERFACE("blue_ram_16k",  ASTROCADE_BLUERAM_16K)
+	SLOT_INTERFACE("blue_ram_32k",  ASTROCADE_BLUERAM_32K)
+	SLOT_INTERFACE("viper_sys1",    ASTROCADE_VIPER_SYS1)
+	SLOT_INTERFACE("lil_white_ram", ASTROCADE_WHITERAM)
+	SLOT_INTERFACE("rl64_ram",      ASTROCADE_RL64RAM)
+SLOT_INTERFACE_END
+
 
 static MACHINE_CONFIG_START( astrocde, astrocde_mess_state )
 	/* basic machine hardware */
@@ -265,7 +190,6 @@ static MACHINE_CONFIG_START( astrocde, astrocde_mess_state )
 	MCFG_CPU_IO_MAP(astrocade_io)
 
 	MCFG_MACHINE_START_OVERRIDE(astrocde_mess_state, astrocde)
-	MCFG_MACHINE_RESET_OVERRIDE(astrocde_mess_state, astrocde)
 
 	/* video hardware */
 	MCFG_SCREEN_ADD("screen", RASTER)
@@ -281,9 +205,8 @@ static MACHINE_CONFIG_START( astrocde, astrocde_mess_state )
 	MCFG_SOUND_ADD("astrocade1", ASTROCADE, ASTROCADE_CLOCK/4)
 	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 1.00)
 
-	/* optional expansion ram (installed in machine_reset)*/
+	/* expansion port */
-	MCFG_RAM_ADD("ram_tag")
+	MCFG_ASTROCADE_EXPANSION_SLOT_ADD("exp", astrocade_exp, NULL)
-	MCFG_RAM_DEFAULT_SIZE("32k")
 
 	/* cartridge */
 	MCFG_ASTROCADE_CARTRIDGE_ADD("cartslot", astrocade_cart, NULL)
@@ -331,80 +254,6 @@ MACHINE_START_MEMBER(astrocde_mess_state, astrocde)
 		m_maincpu->space(AS_PROGRAM).install_read_handler(0x2000, 0x3fff, read8_delegate(FUNC(astrocade_cart_slot_device::read_rom),(astrocade_cart_slot_device*)m_cart));
 }
 
-MACHINE_RESET_MEMBER(astrocde_mess_state, astrocde)
-{
-	int ram_expansion_installed = 0, write_protect_on = 0, expansion_ram_start = 0, expansion_ram_end = 0, shadow_ram_end = 0;
-	address_space &space = m_maincpu->space(AS_PROGRAM);
-	UINT8 *expram = machine().device<ram_device>("ram_tag")->pointer();
-	space.unmap_readwrite(0x5000, 0xffff);  // unmap any previously installed expansion RAM
-
-	get_ram_expansion_settings(ram_expansion_installed, write_protect_on, expansion_ram_start, expansion_ram_end, shadow_ram_end);  // passing by reference
-
-	if (ram_expansion_installed == 1)
-	{
-		if (write_protect_on == 0)  // write protect off, so install memory normally
-		{
-			space.install_ram(expansion_ram_start, expansion_ram_end, expram);
-			if (shadow_ram_end > expansion_ram_end)
-				space.install_ram(expansion_ram_end + 1, shadow_ram_end, expram);
-		}
-		else  // write protect on, so make memory read only
-		{
-			space.nop_write(expansion_ram_start, expansion_ram_end);
-		}
-	}
-}
-
-void astrocde_mess_state::get_ram_expansion_settings(int &ram_expansion_installed, int &write_protect_on, int &expansion_ram_start, int &expansion_ram_end, int &shadow_ram_end)
-{
-	if (ioport("PROTECT")->read() == 0x01)
-		write_protect_on = 1;
-	else
-		write_protect_on = 0;
-
-	ram_expansion_installed = 1;
-
-	switch(ioport("CFG")->read())  // check RAM expansion configuration and set address ranges
-	{
-		case 0x00:  // No RAM Expansion
-				ram_expansion_installed = 0;
-				break;
-		case 0x01:  // 16KB Viper System 1 RAM Expansion
-				expansion_ram_start = 0x6000;
-				expansion_ram_end = 0x9fff;
-				shadow_ram_end = 0;
-				break;
-		case 0x02:  // "32KB Lil' WHITE RAM Expansion
-				expansion_ram_start = 0x5000;
-				expansion_ram_end = 0xcfff;
-				shadow_ram_end = 0xffff;
-				break;
-		case 0x04:  // R&L 64K RAM Board (44KB installed)
-				expansion_ram_start = 0x5000;
-				expansion_ram_end = 0xffff;
-				shadow_ram_end = 0;
-				break;
-		case 0x08:  // 4KB Blue RAM Expansion
-				expansion_ram_start = 0x6000;
-				expansion_ram_end = 0x6fff;
-				shadow_ram_end = 0;
-				break;
-		case 0x10:  // 16KB Blue RAM Expansion
-				expansion_ram_start = 0x6000;
-				expansion_ram_end = 0x9fff;
-				shadow_ram_end = 0;
-				break;
-		case 0x20:  // 32KB Blue RAM Expansion
-				expansion_ram_start = 0x6000;
-				expansion_ram_end = 0xdfff;
-				shadow_ram_end = 0;
-				break;
-		default:
-			break;
-	}
-}
-
-
 /*************************************
  *
  *  Driver definitions