// license:BSD-3-Clause
// copyright-holders:David Haywood

#include "emu.h"
#include "includes/megadriv.h"
#include "sound/sn76496.h"

#include "imagedev/chd_cd.h"

#include "bus/generic/slot.h"
#include "bus/generic/carts.h"

#include "formats/imageutl.h"
#include "softlist.h"

/*************************************
 *
 *  Input handlers
 *
 *************************************/

/* These overwrite the MAME ones in DRIVER_INIT */
/* They're needed to give the users the choice between different controllers */
READ8_MEMBER(md_cons_state::mess_md_io_read_data_port)
{
	int portnum = offset;

	UINT8 retdata;
	int controller;
	UINT8 helper_6b = (m_megadrive_io_ctrl_regs[portnum] & 0x3f) | 0xc0; // bits 6 & 7 always come from megadrive_io_data_regs
	UINT8 helper_3b = (m_megadrive_io_ctrl_regs[portnum] & 0x7f) | 0x80; // bit 7 always comes from megadrive_io_data_regs

	switch (portnum)
	{
		case 0:
			controller = (m_io_ctrlr->read() & 0x0f);
			break;

		case 1:
			controller = (m_io_ctrlr->read() & 0xf0);
			break;

		default:
			controller = 0;
			break;
	}

	/* Are we using a 6 buttons Joypad? */
	if (controller)
	{
		if (m_megadrive_io_data_regs[portnum] & 0x40)
		{
			if (m_io_stage[portnum] == 2)
			{
				/* here we read B, C & the additional buttons */
				retdata = (m_megadrive_io_data_regs[portnum] & helper_6b) |
							((((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0x30) |
								((m_io_pad6b[1][portnum] ? m_io_pad6b[1][portnum]->read() : 0) & 0x0f)) & ~helper_6b);
			}
			else
			{
				/* here we read B, C & the directional buttons */
				retdata = (m_megadrive_io_data_regs[portnum] & helper_6b) |
							(((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0x3f) & ~helper_6b);
			}
		}
		else
		{
			if (m_io_stage[portnum] == 1)
			{
				/* here we read ((Start & A) >> 2) | 0x00 */
				retdata = (m_megadrive_io_data_regs[portnum] & helper_6b) |
							((((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0xc0) >> 2) & ~helper_6b);
			}
			else if (m_io_stage[portnum]==2)
			{
				/* here we read ((Start & A) >> 2) | 0x0f */
				retdata = (m_megadrive_io_data_regs[portnum] & helper_6b) |
							(((((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0xc0) >> 2) | 0x0f) & ~helper_6b);
			}
			else
			{
				/* here we read ((Start & A) >> 2) | Up and Down */
				retdata = (m_megadrive_io_data_regs[portnum] & helper_6b) |
							(((((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0xc0) >> 2) |
								((m_io_pad6b[0][portnum] ? m_io_pad6b[0][portnum]->read() : 0) & 0x03)) & ~helper_6b);
			}
		}

	//  osd_printf_debug("read io data port stage %d port %d %02x\n",mess_io_stage[portnum],portnum,retdata);

		retdata |= (retdata << 8);
	}
	/* Otherwise it's a 3 buttons Joypad */
	else
	{
		UINT8 svp_test = 0;
		if (m_cart)
			svp_test = m_cart->read_test();

		// handle test input for SVP test
		if (portnum == 0 && svp_test)
		{
			retdata = (m_megadrive_io_data_regs[0] & 0xc0);
		}
		else if (m_megadrive_io_data_regs[portnum] & 0x40)
		{
			/* here we read B, C & the directional buttons */
			retdata = (m_megadrive_io_data_regs[portnum] & helper_3b) |
						((((m_io_pad3b[portnum] ? m_io_pad3b[portnum]->read() : 0) & 0x3f) | 0x40) & ~helper_3b);
		}
		else
		{
			/* here we read ((Start & A) >> 2) | Up and Down */
			retdata = (m_megadrive_io_data_regs[portnum] & helper_3b) |
						(((((m_io_pad3b[portnum] ? m_io_pad3b[portnum]->read() : 0) & 0xc0) >> 2) |
							((m_io_pad3b[portnum] ? m_io_pad3b[portnum]->read() : 0) & 0x03) | 0x40) & ~helper_3b);
		}
	}

	return retdata;
}


WRITE16_MEMBER(md_cons_state::mess_md_io_write_data_port)
{
	int portnum = offset;
	int controller;

	switch (portnum)
	{
		case 0:
			controller = (m_io_ctrlr->read() & 0x0f);
			break;

		case 1:
			controller = (m_io_ctrlr->read() & 0xf0);
			break;

		default:
			controller = 0;
			break;
	}

	if (controller)
	{
		if (m_megadrive_io_ctrl_regs[portnum] & 0x40)
		{
			if (((m_megadrive_io_data_regs[portnum] & 0x40) == 0x00) && ((data & 0x40) == 0x40))
			{
				m_io_stage[portnum]++;
				m_io_timeout[portnum]->adjust(m_maincpu->cycles_to_attotime(8192));
			}

		}
	}
	m_megadrive_io_data_regs[portnum] = data;
	//osd_printf_debug("Writing IO Data Register #%d data %04x\n",portnum,data);
}


/*************************************
 *
 *  Input ports
 *
 *************************************/


static INPUT_PORTS_START( md )
	PORT_START("CTRLSEL")   /* Controller selection */
	PORT_CONFNAME( 0x0f, 0x00, "Player 1 Controller" )
	PORT_CONFSETTING( 0x00, "Joystick 3 Buttons" )
	PORT_CONFSETTING( 0x01, "Joystick 6 Buttons" )
//  PORT_CONFSETTING( 0x02, "Sega Mouse" )
/* there exists both a 2 buttons version of the Mouse (Jpn ver, to be used with RPGs, it
    can aslo be used as trackball) and a 3 buttons version (US ver, no trackball feats.) */
//  PORT_CONFSETTING( 0x03, "Sega Menacer" )
//  PORT_CONFSETTING( 0x04, "Konami Justifier" )
//  PORT_CONFSETTING( 0x05, "Team Player (Sega Multitap)" )
//  PORT_CONFSETTING( 0x06, "4-Play (EA Multitap)" )
//  PORT_CONFSETTING( 0x07, "J-Cart" )
	PORT_CONFNAME( 0xf0, 0x00, "Player 2 Controller" )
	PORT_CONFSETTING( 0x00, "Joystick 3 Buttons" )
	PORT_CONFSETTING( 0x10, "Joystick 6 Buttons" )

	PORT_START("PAD1_3B")       /* Joypad 1 (3 button + start) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_JOYSTICK_UP ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0010, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(1) PORT_NAME("P1 B") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_BUTTON3 ) PORT_PLAYER(1) PORT_NAME("P1 C") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(1) PORT_NAME("P1 A") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)
	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_START ) PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x00)

	PORT_START("PAD2_3B")       /* Joypad 2 (3 button + start) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_JOYSTICK_UP ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0010, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(2) PORT_NAME("P2 B") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_BUTTON3 ) PORT_PLAYER(2) PORT_NAME("P2 C") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(2) PORT_NAME("P2 A") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)
	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_START ) PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x00)

	PORT_START("PAD1_6B")       /* Joypad 1 (6 button + start + mode) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_JOYSTICK_UP ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0010, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(1) PORT_NAME("P1 B") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_BUTTON3 ) PORT_PLAYER(1) PORT_NAME("P1 C") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(1) PORT_NAME("P1 A") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_START ) PORT_PLAYER(1) PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)

	PORT_START("EXTRA1")    /* Extra buttons for Joypad 1 (6 button + start + mode) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_BUTTON6 ) PORT_PLAYER(1) PORT_NAME("P1 Z") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_BUTTON5 ) PORT_PLAYER(1) PORT_NAME("P1 Y") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_BUTTON4 ) PORT_PLAYER(1) PORT_NAME("P1 X") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_BUTTON7 ) PORT_PLAYER(1) PORT_NAME("P1 Mode") PORT_CONDITION("CTRLSEL", 0x0f, EQUALS, 0x01)

	PORT_START("PAD2_6B")       /* Joypad 2 (6 button + start + mode) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_JOYSTICK_UP ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0010, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(2) PORT_NAME("P2 B") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_BUTTON3 ) PORT_PLAYER(2) PORT_NAME("P2 C") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(2) PORT_NAME("P2 A") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_START ) PORT_PLAYER(2) PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)

	PORT_START("EXTRA2")    /* Extra buttons for Joypad 2 (6 button + start + mode) NOT READ DIRECTLY */
	PORT_BIT( 0x0001, IP_ACTIVE_LOW, IPT_BUTTON6 ) PORT_PLAYER(2) PORT_NAME("P2 Z") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_BUTTON5 ) PORT_PLAYER(2) PORT_NAME("P2 Y") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_BUTTON4 ) PORT_PLAYER(2) PORT_NAME("P2 X") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)
	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_BUTTON7 ) PORT_PLAYER(2) PORT_NAME("P2 Mode") PORT_CONDITION("CTRLSEL", 0xf0, EQUALS, 0x10)

	PORT_START("RESET")     /* Buttons on Genesis Console */
	PORT_BIT( 0x0001, IP_ACTIVE_HIGH, IPT_SERVICE1 ) PORT_NAME("Reset Button") PORT_IMPULSE(1) // reset, resets 68k (and..?)
INPUT_PORTS_END



/*************************************
 *
 *  Machine driver
 *
 *************************************/

MACHINE_START_MEMBER(md_cons_state, md_common)
{
	static const char *const pad6names[2][4] = {
		{ "PAD1_6B", "PAD2_6B", "UNUSED", "UNUSED" },
		{ "EXTRA1", "EXTRA2", "UNUSED", "UNUSED" }
	};
	static const char *const pad3names[4] = { "PAD1_3B", "PAD2_3B", "UNUSED", "UNUSED" };

	m_io_ctrlr = ioport("CTRLSEL");

	for (int i = 0; i < 4; i++)
	{
		m_io_pad3b[i] = ioport(pad3names[i]);
		m_io_pad6b[0][i] = ioport(pad6names[0][i]);
		m_io_pad6b[1][i] = ioport(pad6names[1][i]);
	}

	// setup timers for 6 button pads
	for (int i = 0; i < 3; i++)
		m_io_timeout[i] = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(md_base_state::io_timeout_timer_callback),this), (void*)(FPTR)i);

	m_vdp->stop_timers();

	if (m_cart)
		m_cart->save_nvram();
}

void md_cons_state::install_cartslot()
{
	// for now m_cartslot is only in MD and not 32x and SegaCD
	m_maincpu->space(AS_PROGRAM).install_readwrite_handler(0x000000, 0x7fffff, read16_delegate(FUNC(base_md_cart_slot_device::read),(base_md_cart_slot_device*)m_cart), write16_delegate(FUNC(base_md_cart_slot_device::write),(base_md_cart_slot_device*)m_cart));
	m_maincpu->space(AS_PROGRAM).install_readwrite_handler(0xa13000, 0xa130ff, read16_delegate(FUNC(base_md_cart_slot_device::read_a13),(base_md_cart_slot_device*)m_cart), write16_delegate(FUNC(base_md_cart_slot_device::write_a13),(base_md_cart_slot_device*)m_cart));
	m_maincpu->space(AS_PROGRAM).install_readwrite_handler(0xa15000, 0xa150ff, read16_delegate(FUNC(base_md_cart_slot_device::read_a15),(base_md_cart_slot_device*)m_cart), write16_delegate(FUNC(base_md_cart_slot_device::write_a15),(base_md_cart_slot_device*)m_cart));
//  m_maincpu->space(AS_PROGRAM).install_write_handler(0xa14000, 0xa14003, write16_delegate(FUNC(base_md_cart_slot_device::write_tmss_bank),(base_md_cart_slot_device*)m_cart));
}

READ16_MEMBER( md_cons_state::tmss_r )
{
	if (offset < 0x4000 / 2)
		return m_tmss[offset];

	return 0xffff;
}

WRITE16_MEMBER( md_cons_state::tmss_swap_w )
{
	if (data & 0x0001)
	{
		install_cartslot();
		m_maincpu->space(AS_PROGRAM).install_write_handler(0xa14100, 0xa14101, write16_delegate(FUNC(md_cons_state::tmss_swap_w),this));
	}
	else
	{
		install_tmss();
	}
}


void md_cons_state::install_tmss()
{
	m_maincpu->space(AS_PROGRAM).unmap_readwrite(0x000000, 0x7fffff);
	m_maincpu->space(AS_PROGRAM).install_read_handler(0x000000, 0x7fffff, read16_delegate(FUNC(md_cons_state::tmss_r),this));

	m_maincpu->space(AS_PROGRAM).install_write_handler(0xa14100, 0xa14101, write16_delegate(FUNC(md_cons_state::tmss_swap_w),this));

}

MACHINE_START_MEMBER(md_cons_state, ms_megadriv)
{
	MACHINE_START_CALL_MEMBER( md_common );

	// the SVP introduces some kind of DMA 'lag', which we have to compensate for, this is obvious even on gfx DMAd from ROM (the Speedometer)
	if (m_cart->get_type() == SEGA_SVP)
		m_vdp->set_dma_delay(2);

	if (m_tmss)
	{
		install_tmss();
	}
	else
	{
		install_cartslot();
	}


}

MACHINE_START_MEMBER(md_cons_state, ms_megacd)
{
	MACHINE_START_CALL_MEMBER( md_common );

	// the segaCD introduces some kind of DMA 'lag', which we have to compensate for,
	// at least when reading wordram? we might need to check what mode we're in the DMA...
	m_vdp->set_dma_delay(2);
}

MACHINE_RESET_MEMBER(md_cons_state, ms_megadriv)
{
	m_maincpu->reset();
	MACHINE_RESET_CALL_MEMBER( megadriv );

	// if the system has a 32x, pause the extra CPUs until they are actually turned on
	if (m_32x)
		m_32x->pause_cpu();
}

// same as screen_eof_megadriv but with addition of 32x and SegaCD/MegaCD pieces
void md_cons_state::screen_eof_console(screen_device &screen, bool state)
{
	if (m_io_reset.read_safe(0) & 0x01)
		m_maincpu->set_input_line(INPUT_LINE_RESET, PULSE_LINE);

	// rising edge
	if (state)
	{
		if (!m_vdp->m_use_alt_timing)
		{
			bool mode3 = (m_vdp->get_imode() == 3);
			m_vdp->vdp_handle_eof();
			m_vdp->m_megadriv_scanline_timer->adjust(attotime::zero);

			if (m_32x)
			{
				m_32x->m_32x_vblank_flag = 0;
				m_32x->m_32x_hcount_compare_val = -1;
				m_32x->update_total_scanlines(mode3);
			}
			if (m_segacd)
				m_segacd->update_total_scanlines(mode3);
		}
	}
}

static MACHINE_CONFIG_START( ms_megadriv, md_cons_state )
	MCFG_FRAGMENT_ADD( md_ntsc )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megadriv)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	MCFG_MD_CARTRIDGE_ADD("mdslot", md_cart, nullptr)
	MCFG_SOFTWARE_LIST_ADD("cart_list","megadriv")
MACHINE_CONFIG_END

static MACHINE_CONFIG_START( ms_megadpal, md_cons_state )
	MCFG_FRAGMENT_ADD( md_pal )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megadriv)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	MCFG_MD_CARTRIDGE_ADD("mdslot", md_cart, nullptr)
	MCFG_SOFTWARE_LIST_ADD("cart_list","megadriv")
MACHINE_CONFIG_END

static MACHINE_CONFIG_DERIVED( genesis_tmss, ms_megadriv )
	MCFG_SOFTWARE_LIST_FILTER("cart_list","TMSS")
MACHINE_CONFIG_END



/*************************************
 *
 *  ROM definition(s)
 *
 *************************************/


/* we don't use the bios rom (it's not needed and only provides security on early models) */

ROM_START(genesis)
	ROM_REGION(MD_CPU_REGION_SIZE, "maincpu", ROMREGION_ERASEFF)
	ROM_REGION( 0x10000, "soundcpu", ROMREGION_ERASEFF)
ROM_END

ROM_START(megadriv)
	ROM_REGION(MD_CPU_REGION_SIZE, "maincpu", ROMREGION_ERASEFF)
	ROM_REGION( 0x10000, "soundcpu", ROMREGION_ERASEFF)
ROM_END

ROM_START(megadrij)
	ROM_REGION(MD_CPU_REGION_SIZE, "maincpu", ROMREGION_ERASEFF)
	ROM_REGION( 0x10000, "soundcpu", ROMREGION_ERASEFF)
ROM_END

ROM_START(genesis_tmss)
	ROM_REGION(MD_CPU_REGION_SIZE, "maincpu", ROMREGION_ERASEFF)
	ROM_REGION( 0x10000, "soundcpu", ROMREGION_ERASEFF)

	ROM_REGION16_BE(0x4000, "tmss", ROMREGION_ERASEFF)
	ROM_LOAD( "tmss_usa.bin", 0x0000,  0x4000, CRC(5f5e64eb) SHA1(453fca4e1db6fae4a10657c4451bccbb71955628) )
ROM_END

/*************************************
 *
 *  Driver initialization
 *
 *************************************/

DRIVER_INIT_MEMBER(md_cons_state, mess_md_common)
{
	m_megadrive_io_read_data_port_ptr = read8_delegate(FUNC(md_cons_state::mess_md_io_read_data_port),this);
	m_megadrive_io_write_data_port_ptr = write16_delegate(FUNC(md_cons_state::mess_md_io_write_data_port),this);
}

DRIVER_INIT_MEMBER(md_cons_state, genesis)
{
	DRIVER_INIT_CALL(megadriv);
	DRIVER_INIT_CALL(mess_md_common);

	if (m_32x)
	{
		m_32x->set_32x_pal(FALSE);
		m_32x->set_framerate(60);
		m_32x->set_total_scanlines(262);
	}
	if (m_segacd)
	{
		m_segacd->set_framerate(60);
		m_segacd->set_total_scanlines(262);
	}

	m_version_hi_nibble = 0x80; // Export NTSC
	if (!m_segacd)
		m_version_hi_nibble |= 0x20;
}

DRIVER_INIT_MEMBER(md_cons_state, md_eur)
{
	DRIVER_INIT_CALL(megadrie);
	DRIVER_INIT_CALL(mess_md_common);

	if (m_32x)
	{
		m_32x->set_32x_pal(TRUE);
		m_32x->set_framerate(50);
		m_32x->set_total_scanlines(313);
	}
	if (m_segacd)
	{
		m_segacd->set_framerate(50);
		m_segacd->set_total_scanlines(313);
	}

	m_version_hi_nibble = 0xc0; // Export PAL
	if (!m_segacd)
		m_version_hi_nibble |= 0x20;
}

DRIVER_INIT_MEMBER(md_cons_state, md_jpn)
{
	DRIVER_INIT_CALL(megadrij);
	DRIVER_INIT_CALL(mess_md_common);

	if (m_32x)
	{
		m_32x->set_32x_pal(FALSE);
		m_32x->set_framerate(60);
		m_32x->set_total_scanlines(262);
	}
	if (m_segacd)
	{
		m_segacd->set_framerate(60);
		m_segacd->set_total_scanlines(262);
	}

	m_version_hi_nibble = 0x00; // JPN NTSC
	if (!m_segacd)
		m_version_hi_nibble |= 0x20;
}

/****************************************** 32X emulation ****************************************/

DEVICE_IMAGE_LOAD_MEMBER( md_cons_state, _32x_cart )
{
	UINT32 length;
	dynamic_buffer temp_copy;
	UINT16 *ROM16;
	UINT32 *ROM32;
	int i;

	if (image.software_entry() == nullptr)
	{
		length = image.length();
		temp_copy.resize(length);
		image.fread(&temp_copy[0], length);
	}
	else
	{
		length = image.get_software_region_length("rom");
		temp_copy.resize(length);
		memcpy(&temp_copy[0], image.get_software_region("rom"), length);
	}

	/* Copy the cart image in the locations the driver expects */
	// Notice that, by using pick_integer, we are sure the code works on both LE and BE machines
	ROM16 = (UINT16 *) memregion("gamecart")->base();
	for (i = 0; i < length; i += 2)
		ROM16[i / 2] = pick_integer_be(&temp_copy[0], i, 2);

	ROM32 = (UINT32 *) memregion("gamecart_sh2")->base();
	for (i = 0; i < length; i += 4)
		ROM32[i / 4] = pick_integer_be(&temp_copy[0], i, 4);

	ROM16 = (UINT16 *) memregion("maincpu")->base();
	for (i = 0x00; i < length; i += 2)
		ROM16[i / 2] = pick_integer_be(&temp_copy[0], i, 2);

	return image_init_result::PASS;
}


void md_cons_state::_32x_scanline_callback(int x, UINT32 priority, UINT16 &lineptr)
{
	if (m_32x)
		m_32x->_32x_render_videobuffer_to_screenbuffer(x, priority, lineptr);
}

void md_cons_state::_32x_interrupt_callback(int scanline, int irq6)
{
	if (m_32x)
		m_32x->_32x_interrupt_cb(scanline, irq6);
}

void md_cons_state::_32x_scanline_helper_callback(int scanline)
{
	if (m_32x)
		m_32x->_32x_render_videobuffer_to_screenbuffer_helper(scanline);
}

static MACHINE_CONFIG_START( genesis_32x, md_cons_state )
	MCFG_FRAGMENT_ADD( md_ntsc )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, md_common)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_DEVICE_MODIFY("gen_vdp")
	MCFG_SEGA315_5313_32X_SCANLINE_CB(md_cons_state, _32x_scanline_callback);
	MCFG_SEGA315_5313_32X_SCANLINE_HELPER_CB(md_cons_state, _32x_scanline_helper_callback);
	MCFG_SEGA315_5313_32X_INTERRUPT_CB(md_cons_state, _32x_interrupt_callback);

	MCFG_DEVICE_ADD("sega32x", SEGA_32X_NTSC, 0)
	MCFG_SEGA_32X_PALETTE("gen_vdp:palette")

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	// we need to remove and re-add the sound system because the balance is different
	// due to MAME / MESS having severe issues if the dac output is > 0.40? (sound is corrupted even if DAC is slient?!)
	MCFG_DEVICE_REMOVE("ymsnd")
	MCFG_DEVICE_REMOVE("snsnd")

	MCFG_SOUND_ADD("ymsnd", YM2612, MASTER_CLOCK_NTSC/7)
	MCFG_SOUND_ROUTE(0, "lspeaker", (0.50)/2)
	MCFG_SOUND_ROUTE(1, "rspeaker", (0.50)/2)

	/* sound hardware */
	MCFG_SOUND_ADD("snsnd", SEGAPSG, MASTER_CLOCK_NTSC/15)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", (0.25)/2)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", (0.25)/2)

	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_MANDATORY
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	MCFG_SOFTWARE_LIST_ADD("cart_list","32x")
	MCFG_SOFTWARE_LIST_FILTER("cart_list","NTSC-U")
MACHINE_CONFIG_END


static MACHINE_CONFIG_START( mdj_32x, md_cons_state )
	MCFG_FRAGMENT_ADD( md_ntsc )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, md_common)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_DEVICE_MODIFY("gen_vdp")
	MCFG_SEGA315_5313_32X_SCANLINE_CB(md_cons_state, _32x_scanline_callback);
	MCFG_SEGA315_5313_32X_SCANLINE_HELPER_CB(md_cons_state, _32x_scanline_helper_callback);
	MCFG_SEGA315_5313_32X_INTERRUPT_CB(md_cons_state, _32x_interrupt_callback);

	MCFG_DEVICE_ADD("sega32x", SEGA_32X_NTSC, 0)
	MCFG_SEGA_32X_PALETTE("gen_vdp:palette")

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	// we need to remove and re-add the sound system because the balance is different
	// due to MAME / MESS having severe issues if the dac output is > 0.40? (sound is corrupted even if DAC is slient?!)
	MCFG_DEVICE_REMOVE("ymsnd")
	MCFG_DEVICE_REMOVE("snsnd")

	MCFG_SOUND_ADD("ymsnd", YM2612, MASTER_CLOCK_NTSC/7)
	MCFG_SOUND_ROUTE(0, "lspeaker", (0.50)/2)
	MCFG_SOUND_ROUTE(1, "rspeaker", (0.50)/2)

	/* sound hardware */
	MCFG_SOUND_ADD("snsnd", SEGAPSG, MASTER_CLOCK_NTSC/15)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", (0.25)/2)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", (0.25)/2)

	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_MANDATORY
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	MCFG_SOFTWARE_LIST_ADD("cart_list","32x")
	MCFG_SOFTWARE_LIST_FILTER("cart_list","NTSC-J")
MACHINE_CONFIG_END


static MACHINE_CONFIG_START( md_32x, md_cons_state )
	MCFG_FRAGMENT_ADD( md_pal )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, md_common)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_DEVICE_MODIFY("gen_vdp")
	MCFG_SEGA315_5313_32X_SCANLINE_CB(md_cons_state, _32x_scanline_callback);
	MCFG_SEGA315_5313_32X_SCANLINE_HELPER_CB(md_cons_state, _32x_scanline_helper_callback);
	MCFG_SEGA315_5313_32X_INTERRUPT_CB(md_cons_state, _32x_interrupt_callback);

	MCFG_DEVICE_ADD("sega32x", SEGA_32X_PAL, 0)
	MCFG_SEGA_32X_PALETTE("gen_vdp:palette")

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	// we need to remove and re-add the sound system because the balance is different
	// due to MAME / MESS having severe issues if the dac output is > 0.40? (sound is corrupted even if DAC is slient?!)
	MCFG_DEVICE_REMOVE("ymsnd")
	MCFG_DEVICE_REMOVE("snsnd")

	MCFG_SOUND_ADD("ymsnd", YM2612, MASTER_CLOCK_NTSC/7)
	MCFG_SOUND_ROUTE(0, "lspeaker", (0.50)/2)
	MCFG_SOUND_ROUTE(1, "rspeaker", (0.50)/2)

	/* sound hardware */
	MCFG_SOUND_ADD("snsnd", SEGAPSG, MASTER_CLOCK_NTSC/15)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "lspeaker", (0.25)/2)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "rspeaker", (0.25)/2)

	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_MANDATORY
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	MCFG_SOFTWARE_LIST_ADD("cart_list","32x")
	MCFG_SOFTWARE_LIST_FILTER("cart_list","PAL")
MACHINE_CONFIG_END



#define _32X_ROMS \
	ROM_REGION16_BE( 0x400000, "gamecart", ROMREGION_ERASE00 ) /* 68000 Code */ \
	ROM_REGION32_BE( 0x400000, "gamecart_sh2", ROMREGION_ERASE00 ) /* Copy for the SH2 */ \
	ROM_REGION16_BE( 0x400000, "32x_68k_bios", 0 ) /* 68000 Code */ \
	ROM_LOAD( "32x_g_bios.bin", 0x000000,  0x000100, CRC(5c12eae8) SHA1(dbebd76a448447cb6e524ac3cb0fd19fc065d944) ) \
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 ) \
	/* temp, rom should only be visible here when one of the regs is set, tempo needs it */ \
	ROM_COPY( "32x_68k_bios", 0x0, 0x0, 0x100) \
	ROM_REGION32_BE( 0x400000, "master", 0 ) /* SH2 Code */ \
	ROM_SYSTEM_BIOS( 0, "retail", "Mars Version 1.0 (retail)" ) \
	ROMX_LOAD( "32x_m_bios.bin", 0x000000,  0x000800, CRC(dd9c46b8) SHA1(1e5b0b2441a4979b6966d942b20cc76c413b8c5e), ROM_BIOS(1) ) \
	ROM_SYSTEM_BIOS( 1, "sdk", "Mars Version 1.0 (early sdk)" ) \
	ROMX_LOAD( "32x_m_bios_sdk.bin", 0x000000,  0x000800, BAD_DUMP CRC(c7102c53) SHA1(ed73a47f186b373b8eff765f84ef26c3d9ef6cb0), ROM_BIOS(2) ) \
	ROM_REGION32_BE( 0x400000, "slave", 0 ) /* SH2 Code */ \
	ROM_LOAD( "32x_s_bios.bin", 0x000000,  0x000400, CRC(bfda1fe5) SHA1(4103668c1bbd66c5e24558e73d4f3f92061a109a) )

ROM_START( 32x )
	_32X_ROMS
ROM_END

ROM_START( 32xe )
	_32X_ROMS
ROM_END

ROM_START( 32xj )
	_32X_ROMS
ROM_END


/****************************************** SegaCD emulation ****************************************/

static MACHINE_CONFIG_START( genesis_scd, md_cons_state )
	MCFG_FRAGMENT_ADD( md_ntsc )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_US, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_SOFTWARE_LIST_ADD("cd_list","segacd")
MACHINE_CONFIG_END

static MACHINE_CONFIG_START( md_scd, md_cons_state )
	MCFG_FRAGMENT_ADD( md_pal )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_EUROPE, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_SOFTWARE_LIST_ADD("cd_list","megacd")
MACHINE_CONFIG_END

static MACHINE_CONFIG_START( mdj_scd, md_cons_state )
	MCFG_FRAGMENT_ADD( md_ntsc )

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)
	MCFG_MACHINE_RESET_OVERRIDE(md_cons_state, ms_megadriv)

	MCFG_SCREEN_MODIFY("megadriv")
	MCFG_SCREEN_VBLANK_DRIVER(md_cons_state, screen_eof_console)

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_JAPAN, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_SOFTWARE_LIST_ADD("cd_list","megacdj")
MACHINE_CONFIG_END

/******************SEGA CD + 32X****************************/

static MACHINE_CONFIG_DERIVED( genesis_32x_scd, genesis_32x )

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_US, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)

	MCFG_DEVICE_REMOVE("cartslot")
	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	//MCFG_QUANTUM_PERFECT_CPU("32x_master_sh2")
	MCFG_SOFTWARE_LIST_ADD("cd_list", "segacd")
MACHINE_CONFIG_END

static MACHINE_CONFIG_DERIVED( md_32x_scd, md_32x )

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_EUROPE, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)

	MCFG_DEVICE_REMOVE("cartslot")
	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	//MCFG_QUANTUM_PERFECT_CPU("32x_master_sh2")
	MCFG_SOFTWARE_LIST_ADD("cd_list", "megacd")
MACHINE_CONFIG_END

static MACHINE_CONFIG_DERIVED( mdj_32x_scd, mdj_32x )

	MCFG_DEVICE_ADD("segacd", SEGA_SEGACD_JAPAN, 0)
	MCFG_GFX_PALETTE("gen_vdp:palette")

	MCFG_CDROM_ADD( "cdrom" )
	MCFG_CDROM_INTERFACE("scd_cdrom")

	MCFG_MACHINE_START_OVERRIDE(md_cons_state, ms_megacd)

	MCFG_DEVICE_REMOVE("cartslot")
	MCFG_GENERIC_CARTSLOT_ADD("cartslot", generic_plain_slot, "_32x_cart")
	MCFG_GENERIC_EXTENSIONS("32x,bin")
	MCFG_GENERIC_LOAD(md_cons_state, _32x_cart)

	//MCFG_QUANTUM_PERFECT_CPU("32x_master_sh2")
	MCFG_SOFTWARE_LIST_ADD("cd_list", "megacdj")
MACHINE_CONFIG_END

/* We need proper names for most of these BIOS ROMs! */
ROM_START( segacd )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v1.10 confirmed dump by dead_screem */
	ROM_LOAD( "mpr-15045b.bin", 0x000000,  0x020000, CRC(c6d10268) SHA1(f4f315adcef9b8feb0364c21ab7f0eaf5457f3ed) )
ROM_END

ROM_START( megacd )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v1.00, confirmed good dump */
	ROM_LOAD( "megacd_model1_bios_1_00_e.bin", 0x000000,  0x020000, CRC(529ac15a) SHA1(f891e0ea651e2232af0c5c4cb46a0cae2ee8f356) )
ROM_END

ROM_START( megacdj )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_DEFAULT_BIOS("v100g")   // this seems the only revision where the cursor in CD menu works, allowing to boot games
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(0, "v100s", "v1.00S")
	ROMX_LOAD( "mpr-14088h.bin", 0x000000,  0x020000, CRC(3773d5aa) SHA1(bbf729a1aaa1667b783749299e1ad932aaf5f253), ROM_BIOS(1) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(1, "v100g", "v1.00G")
	ROMX_LOAD( "epr-14088b.bin", 0x000000,  0x020000, CRC(69ed6ccd) SHA1(27d11c3836506f01ee81cd142c0cd8b51abebbd2), ROM_BIOS(2) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(2, "v100l", "v1.00L")
	ROMX_LOAD( "mpr-14088c.bin", 0x000000,  0x020000, CRC(03134289) SHA1(d60cb5a53f26d6b13e354bc149217587f2301718), ROM_BIOS(3) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(3, "v100o", "v1.00O")
	ROMX_LOAD( "epr-14088d.bin", 0x000000,  0x020000, CRC(dfa95ee9) SHA1(e13666c76fa0a2e94e2f651b26b0fd625bf55f07), ROM_BIOS(4) | ROM_GROUPWORD | ROM_REVERSE)
	ROM_SYSTEM_BIOS(4, "v100p", "v1.00P")   // CRC: e2e70bc8 when byteswapped
	ROMX_LOAD( "epr-14088e.bin", 0x000000,  0x020000, CRC(9d2da8f2) SHA1(4846f448160059a7da0215a5df12ca160f26dd69), ROM_BIOS(5) )
ROM_END

/* Asia bios, when run in USA region will show :
ERROR!
THIS IS A PAL-COMPATIBLE MEGA CD
FOR EXCLUSIVE USE IN SOUTHEAST ASIA.

Confirmed by Jakovasaur
*/
ROM_START( megacda )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_LOAD( "epr-14536h.bin", 0x000000,  0x020000, CRC(550f30bb) SHA1(e4193c6ae44c3cea002707d2a88f1fbcced664de))
ROM_END

ROM_START( segacd2 )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_SYSTEM_BIOS(0, "v211x", "Model 2 v2.11X")
	ROMX_LOAD( "mpr-15764-t.bin", 0x000000,  0x020000, CRC(2e49d72c) SHA1(328a3228c29fba244b9db2055adc1ec4f7a87e6b), ROM_BIOS(1) )
	ROM_SYSTEM_BIOS(1, "v200", "Model 2 v2.00") /* verified dump */
	ROMX_LOAD( "us_scd2_930314.bin", 0x000000,  0x020000, CRC(8af65f58) SHA1(5a8c4b91d3034c1448aac4b5dc9a6484fce51636), ROM_BIOS(2) )
	/* this is reportedly a bad dump, it has many differences from the verified dump and does not boot in Kega */
	/* ROMX_LOAD( "segacd_model2_bios_2_00_u.bin", 0x000000,  0x020000, CRC(340b4be4) SHA1(bd3ee0c8ab732468748bf98953603ce772612704), ROM_BIOS(2) ) */
	ROM_SYSTEM_BIOS(2, "v200w", "Model 2 v2.00W")
	ROMX_LOAD( "segacd_model2_bios_2_00w_u.bin", 0x000000,  0x020000, CRC(9f6f6276) SHA1(5adb6c3af218c60868e6b723ec47e36bbdf5e6f0), ROM_BIOS(3) )
ROM_END

/* All confirmed good dump by ElBarto */
ROM_START( megacd2 )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_SYSTEM_BIOS(0, "v200w", "v2.00W")
	ROMX_LOAD( "mpr-15512a.bin", 0x000000,  0x020000, CRC(53f1757c) SHA1(67bf3970ca5a05fd5ce3d6c446789c5d971b98a4), ROM_BIOS(1) | ROM_GROUPWORD | ROM_REVERSE )
	ROM_SYSTEM_BIOS(1, "v200", "v2.00")
	ROMX_LOAD( "mpr-15512.bin", 0x000000,  0x020000, CRC(cb76f114) SHA1(939f173cadc41e996a3c34498da1bf55e7e18ff8), ROM_BIOS(2) | ROM_GROUPWORD | ROM_REVERSE )
ROM_END

/* Confirmed good dump by ElBarto */
ROM_START( megacd2j )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_SYSTEM_BIOS(0, "v200c", "v2.00C")
	ROMX_LOAD( "mpr-15398.bin", 0x000000,  0x020000, CRC(1e4344e6) SHA1(4d1251a6973d932e734ae5e8c6b9b55eb40e4143), ROM_BIOS(1) | ROM_GROUPWORD | ROM_REVERSE )
ROM_END

ROM_START( aiwamcd )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v2.11 */
	ROM_LOAD( "mpr-15768-t.bin", 0x000000,  0x020000, CRC(8052c7a0) SHA1(219d284dcf63ce366a4dc6d1ff767a0d2eea283d) )
ROM_END

ROM_START( laseract )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_SYSTEM_BIOS(0, "v104", "v1.04")
	ROMX_LOAD( "laseractive_bios_1_04_u.bin", 0x000000,  0x020000, CRC(50cd3d23) SHA1(aa811861f8874775075bd3f53008c8aaf59b07db), ROM_BIOS(1) )
	ROM_SYSTEM_BIOS(1, "v102", "v1.02")
	ROMX_LOAD( "laseractive_bios_1_02_u.bin", 0x000000,  0x020000, CRC(3b10cf41) SHA1(8af162223bb12fc19b414f126022910372790103), ROM_BIOS(2) )
ROM_END

ROM_START( laseractj )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	ROM_SYSTEM_BIOS(0, "v105", "v1.05")
	ROMX_LOAD( "mega-ld 1.05 bios.bin", 0x000000,  0x020000, CRC(474aaa44) SHA1(b3b1d880e288b6dc79eec0ff1b0480c229ec141d), ROM_BIOS(1) )
	ROM_SYSTEM_BIOS(1, "v102", "v1.02")
	ROMX_LOAD( "laseractive_bios_1_02_j.bin", 0x000000,  0x020000, CRC(00eedb3a) SHA1(26237b333db4a4c6770297fa5e655ea95840d5d9), ROM_BIOS(2) )
ROM_END

ROM_START( xeye )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v2.00 (US), confirmed good with a chip dump */
	ROM_LOAD( "g304.bin", 0x000000,  0x020000, CRC(290f8e33) SHA1(651f14d5a5e0ecb974a60c0f43b1d2006323fb09) )
ROM_END

ROM_START( wmega )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v1.00 (Japan NTSC) Sega BIOS, chip-dumped */
	ROM_LOAD( "g301.bin", 0x000000,  0x020000, CRC(d21fe71d) SHA1(3fc9358072f74bd24e3e297ea11b2bf15a7af891) )
ROM_END

ROM_START( wmegam2 )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v2.00 */
	ROM_LOAD( "wondermega_m2_bios_2_00_j.bin", 0x000000,  0x020000, CRC(2b19972f) SHA1(b3f32e409bd5508c89ed8be33d41a58d791d0e5d) )
ROM_END

ROM_START( cdx )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v2.21X */
	ROM_LOAD( "segacdx_bios_2_21_u.bin", 0x000000,  0x020000, CRC(d48c44b5) SHA1(2b125c0545afa089b617f2558e686ea723bdc06e) )
ROM_END

ROM_START( multmega )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )
	/* v2.21X */
	ROM_LOAD( "opr-16140.bin", 0x000000,  0x020000, CRC(aacb851e) SHA1(75548ac9aaa6e81224499f9a1403b2b42433f5b7) )
	/* the below was marked "confirmed good dump", but 0x72 and 0x73 are 0xFF, indicating a bad dump made from memory */
	/* ROM_LOAD( "multimega_bios_2_21_e.bin", 0x000000,  0x020000, CRC(34d3cce1) SHA1(73fc9c014ad803e9e7d8076b3642a8a5224b3e51) ) */
ROM_END

/* some games use the 32x and SegaCD together to give better quality FMV */
ROM_START( 32x_scd )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )

	ROM_REGION16_BE( 0x400000, "gamecart", 0 ) /* 68000 Code */
	ROM_LOAD( "mpr-15764-t.bin", 0x000000,  0x020000, CRC(2e49d72c) SHA1(328a3228c29fba244b9db2055adc1ec4f7a87e6b) )

	ROM_REGION32_BE( 0x400000, "gamecart_sh2", 0 ) /* Copy for the SH2 */
	ROM_COPY( "gamecart", 0x000000, 0x0, 0x400000)

	ROM_REGION16_BE( 0x400000, "32x_68k_bios", 0 ) /* 68000 Code */
	ROM_LOAD( "32x_g_bios.bin", 0x000000,  0x000100, CRC(5c12eae8) SHA1(dbebd76a448447cb6e524ac3cb0fd19fc065d944) )

	ROM_REGION32_BE( 0x400000, "master", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_m_bios.bin", 0x000000,  0x000800, CRC(dd9c46b8) SHA1(1e5b0b2441a4979b6966d942b20cc76c413b8c5e) )

	ROM_REGION32_BE( 0x400000, "slave", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_s_bios.bin", 0x000000,  0x000400, CRC(bfda1fe5) SHA1(4103668c1bbd66c5e24558e73d4f3f92061a109a) )
ROM_END

ROM_START( 32x_mcd )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )

	ROM_REGION16_BE( 0x400000, "gamecart", 0 ) /* 68000 Code */
	ROM_LOAD( "megacd_model1_bios_1_00_e.bin", 0x000000,  0x020000, CRC(529ac15a) SHA1(f891e0ea651e2232af0c5c4cb46a0cae2ee8f356) )

	ROM_REGION32_BE( 0x400000, "gamecart_sh2", 0 ) /* Copy for the SH2 */
	ROM_COPY( "gamecart", 0x000000, 0x0, 0x400000)

	ROM_REGION16_BE( 0x400000, "32x_68k_bios", 0 ) /* 68000 Code */
	ROM_LOAD( "32x_g_bios.bin", 0x000000,  0x000100, CRC(5c12eae8) SHA1(dbebd76a448447cb6e524ac3cb0fd19fc065d944) )

	ROM_REGION32_BE( 0x400000, "master", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_m_bios.bin", 0x000000,  0x000800, CRC(dd9c46b8) SHA1(1e5b0b2441a4979b6966d942b20cc76c413b8c5e) )

	ROM_REGION32_BE( 0x400000, "slave", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_s_bios.bin", 0x000000,  0x000400, CRC(bfda1fe5) SHA1(4103668c1bbd66c5e24558e73d4f3f92061a109a) )
ROM_END

ROM_START( 32x_mcdj )
	ROM_REGION16_BE( 0x400000, "maincpu", ROMREGION_ERASE00 )

	ROM_REGION16_BE( 0x400000, "gamecart", 0 ) /* 68000 Code */
	ROM_DEFAULT_BIOS("v100g")   // this seems the only revision where the cursor in CD menu works, allowing to boot games
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(0, "v100s", "v1.00S")
	ROMX_LOAD( "mpr-14088h.bin", 0x000000,  0x020000, CRC(3773d5aa) SHA1(bbf729a1aaa1667b783749299e1ad932aaf5f253), ROM_BIOS(1) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(1, "v100g", "v1.00G")
	ROMX_LOAD( "epr-14088b.bin", 0x000000,  0x020000, CRC(69ed6ccd) SHA1(27d11c3836506f01ee81cd142c0cd8b51abebbd2), ROM_BIOS(2) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(2, "v100l", "v1.00L")
	ROMX_LOAD( "mpr-14088c.bin", 0x000000,  0x020000, CRC(03134289) SHA1(d60cb5a53f26d6b13e354bc149217587f2301718), ROM_BIOS(3) | ROM_GROUPWORD | ROM_REVERSE)
	/* Confirmed by ElBarto */
	ROM_SYSTEM_BIOS(3, "v100o", "v1.00O")
	ROMX_LOAD( "epr-14088d.bin", 0x000000,  0x020000, CRC(dfa95ee9) SHA1(e13666c76fa0a2e94e2f651b26b0fd625bf55f07), ROM_BIOS(4) | ROM_GROUPWORD | ROM_REVERSE)
	ROM_SYSTEM_BIOS(4, "v100p", "v1.00P")   // CRC: e2e70bc8 when byteswapped
	ROMX_LOAD( "epr-14088e.bin", 0x000000,  0x020000, CRC(9d2da8f2) SHA1(4846f448160059a7da0215a5df12ca160f26dd69), ROM_BIOS(5) )

	ROM_REGION32_BE( 0x400000, "gamecart_sh2", 0 ) /* Copy for the SH2 */
	ROM_COPY( "gamecart", 0x000000, 0x0, 0x400000)

	ROM_REGION16_BE( 0x400000, "32x_68k_bios", 0 ) /* 68000 Code */
	ROM_LOAD( "32x_g_bios.bin", 0x000000,  0x000100, CRC(5c12eae8) SHA1(dbebd76a448447cb6e524ac3cb0fd19fc065d944) )

	ROM_REGION32_BE( 0x400000, "master", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_m_bios.bin", 0x000000,  0x000800, CRC(dd9c46b8) SHA1(1e5b0b2441a4979b6966d942b20cc76c413b8c5e) )

	ROM_REGION32_BE( 0x400000, "slave", 0 ) /* SH2 Code */
	ROM_LOAD( "32x_s_bios.bin", 0x000000,  0x000400, CRC(bfda1fe5) SHA1(4103668c1bbd66c5e24558e73d4f3f92061a109a) )
ROM_END



/***************************************************************************

  Game driver(s)

***************************************************************************/

/*    YEAR  NAME        PARENT     COMPAT  MACHINE          INPUT   INIT       COMPANY   FULLNAME */
CONS( 1989, genesis,    0,         0,      ms_megadriv,     md, md_cons_state,     genesis,   "Sega",   "Genesis (USA, NTSC)",  MACHINE_SUPPORTS_SAVE )
CONS( 1990, megadriv,   genesis,   0,      ms_megadpal,     md, md_cons_state,     md_eur,    "Sega",   "Mega Drive (Europe, PAL)", MACHINE_SUPPORTS_SAVE )
CONS( 1988, megadrij,   genesis,   0,      ms_megadriv,     md, md_cons_state,     md_jpn,    "Sega",   "Mega Drive (Japan, NTSC)", MACHINE_SUPPORTS_SAVE )

// 1990+ models had the TMSS security chip, leave this as a clone, it reduces compatibility and nothing more.
CONS( 1990, genesis_tmss, genesis, 0,      genesis_tmss,    md, md_cons_state,     genesis,   "Sega",   "Genesis (USA, NTSC, with TMSS chip)",  MACHINE_SUPPORTS_SAVE )


// the 32X plugged in the cart slot, games plugged into the 32x.  Maybe it should be handled as an expansion device?
CONS( 1994, 32x,        0,         0,      genesis_32x,     md, md_cons_state,     genesis,   "Sega",   "Genesis with 32X (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1994, 32xe,       32x,       0,      md_32x,          md, md_cons_state,     md_eur,    "Sega",   "Mega Drive with 32X (Europe, PAL)", MACHINE_NOT_WORKING )
CONS( 1994, 32xj,       32x,       0,      mdj_32x,         md, md_cons_state,     md_jpn,    "Sega",   "Mega Drive with 32X (Japan, NTSC)", MACHINE_NOT_WORKING )

// the SegaCD plugged into the expansion port..
CONS( 1992, segacd,     0,         0,      genesis_scd,     md, md_cons_state,     genesis,   "Sega",   "Sega CD (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, megacd,     segacd,    0,      md_scd,          md, md_cons_state,     md_eur,    "Sega",   "Mega-CD (Europe, PAL)", MACHINE_NOT_WORKING )
CONS( 1991, megacdj,    segacd,    0,      mdj_scd,         md, md_cons_state,     md_jpn,    "Sega",   "Mega-CD (Japan, NTSC)", MACHINE_NOT_WORKING ) // this bios doesn't work with our ram interleave needed by a few games?!
CONS( 1991, megacda,    segacd,    0,      md_scd,          md, md_cons_state,     md_eur,    "Sega",   "Mega-CD (Asia, PAL)", MACHINE_NOT_WORKING )
CONS( 1993, segacd2,    0,         0,      genesis_scd,     md, md_cons_state,     genesis,   "Sega",   "Sega CD 2 (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, megacd2,    segacd2,   0,      md_scd,          md, md_cons_state,     md_eur,    "Sega",   "Mega-CD 2 (Europe, PAL)", MACHINE_NOT_WORKING )
CONS( 1993, megacd2j,   segacd2,   0,      mdj_scd,         md, md_cons_state,     md_jpn,    "Sega",   "Mega-CD 2 (Japan, NTSC)", MACHINE_NOT_WORKING )
CONS( 1994, aiwamcd,    segacd2,   0,      mdj_scd,         md, md_cons_state,     md_jpn,    "AIWA",   "Mega-CD CSD-G1M (Japan, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, laseract,   0,         0,      genesis_scd,     md, md_cons_state,     genesis,   "Pioneer","LaserActive (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, laseractj,  laseract,  0,      mdj_scd,         md, md_cons_state,     md_jpn,    "Pioneer","LaserActive (Japan, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, xeye,       0,         0,      genesis_scd,     md, md_cons_state,     genesis,   "JVC",    "X'eye (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1992, wmega,      xeye,      0,      mdj_scd,         md, md_cons_state,     md_jpn,    "Sega",   "Wondermega (Japan, NTSC)", MACHINE_NOT_WORKING )
CONS( 1993, wmegam2,    xeye,      0,      mdj_scd,         md, md_cons_state,     md_jpn,    "Victor", "Wondermega M2 (Japan, NTSC)", MACHINE_NOT_WORKING )
CONS( 1994, cdx,        0,         0,      genesis_scd,     md, md_cons_state,     genesis,   "Sega",   "CDX (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1994, multmega,   cdx,       0,      md_scd,          md, md_cons_state,     md_eur,    "Sega",   "Multi-Mega (Europe, PAL)", MACHINE_NOT_WORKING )

//32X plugged in the cart slot + SegaCD plugged into the expansion port..
CONS( 1994, 32x_scd,    0,         0,      genesis_32x_scd, md, md_cons_state,     genesis,   "Sega",   "Sega CD with 32X (USA, NTSC)", MACHINE_NOT_WORKING )
CONS( 1995, 32x_mcd,    32x_scd,   0,      md_32x_scd,      md, md_cons_state,     md_eur,    "Sega",   "Mega-CD with 32X (Europe, PAL)", MACHINE_NOT_WORKING )
CONS( 1994, 32x_mcdj,   32x_scd,   0,      mdj_32x_scd,     md, md_cons_state,     md_jpn,    "Sega",   "Mega-CD with 32X (Japan, NTSC)", MACHINE_NOT_WORKING )
