(MESS) abc80: Emulated a 16KB RAM card. [Curt Coder]

scripts/src/bus.lua

@@ -69,10 +69,11 @@ if (BUSES["ABCBUS"]~=null) then
 		MAME_DIR .. "src/emu/bus/abcbus/lux21056.c",
 		MAME_DIR .. "src/emu/bus/abcbus/lux4105.c",
 		MAME_DIR .. "src/emu/bus/abcbus/memcard.c",
-		MAME_DIR .. "src/emu/bus/abcbus/uni800.c",
+		MAME_DIR .. "src/emu/bus/abcbus/ram.c",
 		MAME_DIR .. "src/emu/bus/abcbus/sio.c",
 		MAME_DIR .. "src/emu/bus/abcbus/slutprov.c",
 		MAME_DIR .. "src/emu/bus/abcbus/turbo.c",
+		MAME_DIR .. "src/emu/bus/abcbus/uni800.c",
 	}
 end
 

src/emu/bus/abcbus/abc890.c

@@ -61,7 +61,7 @@ static MACHINE_CONFIG_FRAGMENT( abc_expansion_unit )
 	MCFG_ABCBUS_SLOT_ADD("io3", abc80_cards, NULL)
 	MCFG_ABCBUS_SLOT_ADD("io4", abc80_cards, NULL)
 	MCFG_ABCBUS_SLOT_ADD("mem1", abc80_cards, "memcard")
-	MCFG_ABCBUS_SLOT_ADD("mem2", abc80_cards, NULL)
+	MCFG_ABCBUS_SLOT_ADD("mem2", abc80_cards, "16k")
 	MCFG_ABCBUS_SLOT_ADD("mem3", abc80_cards, NULL)
 MACHINE_CONFIG_END
 

src/emu/bus/abcbus/abcbus.c

@@ -89,10 +89,11 @@ void abcbus_slot_t::device_start()
 #include "lux21056.h"
 #include "lux4105.h"
 #include "memcard.h"
-#include "uni800.h"
+#include "ram.h"
 #include "sio.h"
 #include "slutprov.h"
 #include "turbo.h"
+#include "uni800.h"
 
 
 
@@ -104,6 +105,7 @@ SLOT_INTERFACE_START( abc80_cards )
 	SLOT_INTERFACE("fd2", ABC_FD2)
 	SLOT_INTERFACE("memcard", ABC_MEMORY_CARD)
 	SLOT_INTERFACE("abcexp", ABC_EXPANSION_UNIT)
+	SLOT_INTERFACE("16k", ABC80_16KB_RAM_CARD)
 	SLOT_INTERFACE("slow", LUXOR_55_10828)
 SLOT_INTERFACE_END
 

src/emu/bus/abcbus/ram.c

@@ -0,0 +1,82 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+    ABC 80 16 KB RAM expansion card emulation
+
+    Copyright MESS Team.
+    Visit http://mamedev.org for licensing and usage restrictions.
+
+*********************************************************************/
+
+#include "ram.h"
+
+
+
+//**************************************************************************
+//  DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type ABC80_16KB_RAM_CARD = &device_creator<abc80_16kb_ram_card_t>;
+
+
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+//  abc80_16kb_ram_card_t - constructor
+//-------------------------------------------------
+
+abc80_16kb_ram_card_t::abc80_16kb_ram_card_t(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+	device_t(mconfig, ABC80_16KB_RAM_CARD, "ABC 80 16KB RAM card", tag, owner, clock, "abc80_16kb", __FILE__),
+	device_abcbus_card_interface(mconfig, *this),
+	m_ram(*this, "ram")
+{
+}
+
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void abc80_16kb_ram_card_t::device_start()
+{
+	m_ram.allocate(0x4000);
+}
+
+
+
+//**************************************************************************
+//  ABC BUS INTERFACE
+//**************************************************************************
+
+//-------------------------------------------------
+//  abcbus_xmemfl -
+//-------------------------------------------------
+
+UINT8 abc80_16kb_ram_card_t::abcbus_xmemfl(offs_t offset)
+{
+	UINT8 data = 0xff;
+
+	if (offset >= 0x8000 && offset < 0xc000)
+	{
+		data = m_ram[offset & 0x3fff];
+	}
+
+	return data;
+}
+
+
+//-------------------------------------------------
+//  abcbus_xmemw -
+//-------------------------------------------------
+
+void abc80_16kb_ram_card_t::abcbus_xmemw(offs_t offset, UINT8 data)
+{
+	if (offset >= 0x8000 && offset < 0xc000)
+	{
+		m_ram[offset & 0x3fff] = data;
+	}
+}

src/emu/bus/abcbus/ram.h

@@ -0,0 +1,54 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+    ABC 80 16 KB RAM expansion card emulation
+
+    Copyright MESS Team.
+    Visit http://mamedev.org for licensing and usage restrictions.
+
+*********************************************************************/
+
+#pragma once
+
+#ifndef __ABC80_16KB_RAM_CARD__
+#define __ABC80_16KB_RAM_CARD__
+
+#include "emu.h"
+#include "abcbus.h"
+
+
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+// ======================> abc80_16kb_ram_card_t
+
+class abc80_16kb_ram_card_t :  public device_t,
+						   	   public device_abcbus_card_interface
+{
+public:
+	// construction/destruction
+	abc80_16kb_ram_card_t(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+
+protected:
+	// device-level overrides
+	virtual void device_start();
+
+	// device_abcbus_interface overrides
+	virtual void abcbus_cs(UINT8 data) { };
+	virtual UINT8 abcbus_xmemfl(offs_t offset);
+	virtual void abcbus_xmemw(offs_t offset, UINT8 data);
+
+private:
+	optional_shared_ptr<UINT8> m_ram;
+};
+
+
+// device type definition
+extern const device_type ABC80_16KB_RAM_CARD;
+
+
+
+#endif

src/mess/drivers/abc80.c

@@ -65,7 +65,6 @@ Notes:
 
     TODO:
 
-	- 8KB RAM card
     - proper keyboard controller emulation
     - MyAB TKN80 80-column card
     - GeJo 80-column card
@@ -481,7 +480,8 @@ QUICKLOAD_LOAD_MEMBER( abc80_state, bac )
 {
 	address_space &space = m_maincpu->space(AS_PROGRAM);
 
-	offs_t address = 0xc000;
+	offs_t address = space.read_byte(BOFA + 1) << 8 | space.read_byte(BOFA);
+	if (LOG) logerror("BOFA %04x\n",address);
 
 	dynamic_buffer data;
 	data.resize(quickload_size);
@@ -492,10 +492,12 @@ QUICKLOAD_LOAD_MEMBER( abc80_state, bac )
 	offs_t eofa = address;
 	space.write_byte(EOFA, eofa & 0xff);
 	space.write_byte(EOFA + 1, eofa >> 8);
+	if (LOG) logerror("EOFA %04x\n",address);
 
 	offs_t head = address + 1;
 	space.write_byte(HEAD, head & 0xff);
 	space.write_byte(HEAD + 1, head >> 8);
+	if (LOG) logerror("HEAD %04x\n",address);
 
 	return IMAGE_INIT_PASS;
 }