apple3: Preliminary support for Microsoft SoftCard /// [Rob Justice, R. Belmont]

scripts/src/bus.lua

@@ -2476,6 +2476,8 @@ if (BUSES["A2BUS"]~=null) then
 		MAME_DIR .. "src/devices/bus/a2bus/ramcard16k.h",
 		MAME_DIR .. "src/devices/bus/a2bus/sider.cpp",
 		MAME_DIR .. "src/devices/bus/a2bus/sider.h",
+		MAME_DIR .. "src/devices/bus/a2bus/softcard3.cpp",
+		MAME_DIR .. "src/devices/bus/a2bus/softcard3.h",
 		MAME_DIR .. "src/devices/bus/a2bus/ssbapple.cpp",
 		MAME_DIR .. "src/devices/bus/a2bus/ssbapple.h",
 		MAME_DIR .. "src/devices/bus/a2bus/ssprite.cpp",

src/devices/bus/a2bus/softcard3.cpp

@@ -0,0 +1,226 @@
+// license:BSD-3-Clause
+// copyright-holders:Rob Justice, R. Belmont
+/*********************************************************************
+
+    softcard3.cpp
+
+    Implementation of the Microsoft SoftCard /// Z-80 card
+
+    Best guess at the moment based on disassembly of the boot disk
+    and some manual checks with the real hardware
+
+*********************************************************************/
+
+#include "emu.h"
+#include "softcard3.h"
+#include "cpu/z80/z80.h"
+
+/***************************************************************************
+    PARAMETERS
+***************************************************************************/
+
+//**************************************************************************
+//  GLOBAL VARIABLES
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(A2BUS_SOFTCARD3, a2bus_softcard3_device, "softcard3", "Microsoft SoftCard ///")
+
+void a2bus_softcard3_device::z80_mem(address_map &map)
+{
+	map(0x0000, 0xffff).rw(FUNC(a2bus_softcard3_device::dma_r), FUNC(a2bus_softcard3_device::dma_w));
+}
+
+ROM_START( softcard3 )
+	ROM_REGION(0x100, "mapping_prom", 0)
+	ROM_LOAD("softcard3.rom", 0x0000, 0x0100, CRC(9d4433b2) SHA1(aff45dd8850641b4616b61750c104e7ee45a99a4))
+ROM_END
+
+void a2bus_softcard3_device::z80_io(address_map &map)
+{
+	map(0x00, 0x00).w(FUNC(a2bus_softcard3_device::z80_io_w));
+}
+
+/***************************************************************************
+    FUNCTION PROTOTYPES
+***************************************************************************/
+
+//-------------------------------------------------
+//  device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void a2bus_softcard3_device::device_add_mconfig(machine_config &config)
+{
+	Z80(config, m_z80, 1021800*2);   // Z80 runs at 2M based on comment in the manual
+	m_z80->set_addrmap(AS_PROGRAM, &a2bus_softcard3_device::z80_mem);
+	m_z80->set_addrmap(AS_IO, &a2bus_softcard3_device::z80_io);
+	TIMER(config, "timer").configure_generic(FUNC(a2bus_softcard3_device::timercallback));
+}
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+a2bus_softcard3_device::a2bus_softcard3_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+	device_t(mconfig, type, tag, owner, clock),
+	device_a2bus_card_interface(mconfig, *this),
+	m_z80(*this, "z80"),
+	m_prom(*this, "mapping_prom"),
+	m_timer(*this, "timer"),
+	m_bEnabled(false),
+	m_reset(false),
+	m_enable_fffx(false)
+{
+}
+
+a2bus_softcard3_device::a2bus_softcard3_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	a2bus_softcard3_device(mconfig, A2BUS_SOFTCARD3, tag, owner, clock)
+{
+}
+
+const tiny_rom_entry *a2bus_softcard3_device::device_rom_region() const
+{
+	return ROM_NAME(softcard3);
+}
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void a2bus_softcard3_device::device_start()
+{
+	save_item(NAME(m_bEnabled));
+	save_item(NAME(m_reset));
+	save_item(NAME(m_enable_fffx));
+}
+
+void a2bus_softcard3_device::device_reset()
+{
+	m_bEnabled = false;
+	m_reset = false;
+	m_enable_fffx = false;
+	m_z80->set_input_line(INPUT_LINE_HALT, ASSERT_LINE);
+	m_timer->adjust(attotime::never);
+}
+
+uint8_t a2bus_softcard3_device::read_c0nx(uint8_t offset)
+{
+	return 0x50; //software is looking for 0x50, needs to be checked if this can return other flags
+}
+
+void a2bus_softcard3_device::write_c0nx(uint8_t offset, uint8_t data)
+{
+	switch (data)
+	{
+		case 0x01: // reset
+			m_reset = true; // flag we need a reset when we enable the Z80
+			break;
+
+		case 0x10: // enable the card fffc & fffd memory mapped address to appear
+			m_enable_fffx = true;
+			break;
+
+		default:
+			//printf("Softcard3: %02x to unhandled c0n%x\n", data, offset);
+			break;
+	}
+}
+
+// read to fffc halts 6502 and enables z80
+uint8_t a2bus_softcard3_device::read_inh_rom(uint16_t offset)
+{
+	if (offset == 0xfffc)
+	{
+		m_bEnabled = true;
+		raise_slot_dma();
+		m_z80->set_input_line(INPUT_LINE_HALT, CLEAR_LINE);
+		if (m_reset)
+		{
+			m_z80->reset();
+		}
+		m_timer->adjust(attotime::from_hz(5.0)); //start supervision timer
+		//printf("timer start\n");
+	}
+
+	if (offset == 0xfffd)
+	{
+		m_timer->adjust(attotime::never); //disable supervision timer
+		//printf("disable timer\n");
+	}
+
+	return 0xff;
+}
+
+// returns if we want to /INH a read or write to a specific address
+bool a2bus_softcard3_device::inh_check(u16 offset, bool bIsWrite)
+{
+	if (!m_enable_fffx)
+	{
+		return false;
+	}
+
+	if (!(bIsWrite) && (offset == 0xfffc)) //only a read to fffc is mapped in
+	{
+		return true;
+	}
+
+	if (!(bIsWrite) && (offset == 0xfffd)) //only a read to fffd is mapped in
+	{
+		return true;
+	}
+
+	return false;
+}
+
+// this io write halts the z80 and returns to the 6502
+void a2bus_softcard3_device::z80_io_w(offs_t offset, uint8_t data)
+{
+	m_z80->set_input_line(INPUT_LINE_HALT, ASSERT_LINE);
+	lower_slot_dma();
+	m_bEnabled = false;
+	m_enable_fffx = false;
+	m_reset = false;
+	m_timer->adjust(attotime::never);
+	//printf("z80 io timer stop\n");
+}
+
+// fires if Z80 has not handed back to the 6502 in this timer period
+// this ensures 6502 can run and service console i/o
+//  actual time to be checked on real hw
+TIMER_DEVICE_CALLBACK_MEMBER(a2bus_softcard3_device::timercallback)
+{
+	m_z80->set_input_line(INPUT_LINE_HALT, ASSERT_LINE);
+	lower_slot_dma();
+	m_bEnabled = false;
+	m_enable_fffx = false;
+	m_reset = false;
+	//printf("timer callback stop\n");
+}
+
+//memory mapping based on a dump of the mapping rom 256x8
+//maps the top 8 address lines
+uint8_t a2bus_softcard3_device::dma_r(offs_t offset)
+{
+	if (m_bEnabled)
+	{
+		return slot_dma_read((offset & 0xff) + (m_prom[offset >> 8] << 8));
+	}
+
+	return 0xff;
+}
+
+//-------------------------------------------------
+//  dma_w -
+//-------------------------------------------------
+
+void a2bus_softcard3_device::dma_w(offs_t offset, uint8_t data)
+{
+	if (m_bEnabled)
+	{
+		slot_dma_write((offset & 0xff) + (m_prom[offset >> 8] << 8), data);
+	}
+}
+
+bool a2bus_softcard3_device::take_c800()
+{
+	return false;
+}

src/devices/bus/a2bus/softcard3.h

@@ -0,0 +1,66 @@
+// license:BSD-3-Clause
+// copyright-holders:Rob Justice, R. Belmont
+/*********************************************************************
+
+    softcard3.h
+
+    Implementation of the Microsoft SoftCard /// Z-80 card
+
+*********************************************************************/
+
+#ifndef MAME_BUS_A2BUS_SOFTCARD3_H
+#define MAME_BUS_A2BUS_SOFTCARD3_H
+
+#include "a2bus.h"
+#include "machine/timer.h"
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+class a2bus_softcard3_device:
+	public device_t,
+	public device_a2bus_card_interface
+{
+public:
+
+	// construction/destruction
+	a2bus_softcard3_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+	void z80_io_w(offs_t offset, uint8_t data);
+
+protected:
+	a2bus_softcard3_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
+
+	virtual void device_start() override;
+	virtual void device_reset() override;
+	virtual void device_add_mconfig(machine_config &config) override;
+	virtual const tiny_rom_entry *device_rom_region() const override;
+
+	// overrides of standard a2bus slot functions
+	virtual uint8_t read_c0nx(uint8_t offset) override;
+	virtual void write_c0nx(uint8_t offset, uint8_t data) override;
+	virtual bool take_c800() override;
+	virtual u8 read_inh_rom(u16 offset) override;
+	virtual bool inh_check(uint16_t offset, bool bIsWrite) override;
+	TIMER_DEVICE_CALLBACK_MEMBER(timercallback);
+
+private:
+	required_device<cpu_device> m_z80;
+	required_region_ptr<u8> m_prom;
+	required_device<timer_device> m_timer;
+	bool m_bEnabled;
+	bool m_reset;
+	bool m_enable_fffx;
+
+	uint8_t dma_r(offs_t offset);
+	void dma_w(offs_t offset, uint8_t data);
+
+	void z80_io(address_map &map);
+	void z80_mem(address_map &map);
+};
+
+// device type definition
+DECLARE_DEVICE_TYPE(A2BUS_SOFTCARD3, a2bus_softcard3_device)
+
+#endif // MAME_BUS_A2BUS_SOFTCARD3_H

src/mame/drivers/apple3.cpp

@@ -28,6 +28,7 @@
 #include "bus/a2bus/cmsscsi.h"
 #include "bus/a2bus/titan3plus2.h"
 #include "bus/a2bus/a2mockingboard.h"
+#include "bus/a2bus/softcard3.h"
 
 #include "bus/rs232/rs232.h"
 
@@ -50,7 +51,8 @@ static void apple3_cards(device_slot_interface &device)
 	device.option_add("focusdrive", A2BUS_FOCUSDRIVE);  // Focus Drive IDE card
 	device.option_add("cmsscsi", A2BUS_CMSSCSI);        // CMS Apple II SCSI Card
 	device.option_add("titan3plus2", A2BUS_TITAN3PLUS2); // Titan /// Plus 2 card
-	device.option_add("mockingboard", A2BUS_MOCKINGBOARD);
+	device.option_add("mockingboard", A2BUS_MOCKINGBOARD); // Sweet Micro Systems Mockingboard (experimental on ///)
+	device.option_add("softcard3", A2BUS_SOFTCARD3);	// Microsoft SoftCard ///
 }
 
 static void a3_floppies(device_slot_interface &device)