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// license:MAME|LGPL-2.1+
// copyright-holders:Jonathan Gevaryahu
/******************************************************************************
*
*  V-tech Socrates Driver
*  Copyright (C) 2009-2013 Jonathan Gevaryahu AKA Lord Nightmare
*  with dumping help from Kevin 'kevtris' Horton
*
*
*  This source file is dual-licensed under the following licenses:
*  1. The MAME license as of September 2013
*  2. The GNU LGPLv2.1:
*
*  This library is free software; you can redistribute it and/or
*  modify it under the terms of the GNU Lesser General Public
*  License as published by the Free Software Foundation; either
*  version 2.1 of the License, or (at your option) any later version.
*
*  This library is distributed in the hope that it will be useful,
*  but WITHOUT ANY WARRANTY; without even the implied warranty of
*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
*  Lesser General Public License for more details.
*
*  You should have received a copy of the GNU Lesser General Public
*  License along with this library; if not, write to the Free Software
*  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*
*  Please contact the author if you require other licensing.
*
*
TODO:
    * The speech chip is a Toshiba tc8802AF (which is pin and speech
      compatible with the older Toshiba t6803, but adds vsm rom read mode and
      apparently does away with the melody mode); the chip is running at
      800khz clock/10khz output with between 1 and 4 t6684F vsm roms
      attached; create a sound driver for this!
    * fix glitches with keyboard input (double keys still don't work, super painter letter entry still doesn't work)
    * hook up hblank (m_hblankstate is inited 0 right now and never changed)
    * hook up mouse
    * add waitstates for ram access (lack of this causes the system to run
      way too fast)
      This will require some probing with the LA and the fluke to figure out
      how many cycles the waitstates are for for rom/ram/etc access.
    * figure out what bit 6 of the status register actually does; is this an
      ir mcu flag?
    * keyboard IR decoder MCU is HLE'd for now, needs decap and cpu core (it
      is rather tms1000 or CIC-like iirc)


  Socrates Educational Video System
        FFFF|----------------|
            | RAM (window 1) |
            |                |
        C000|----------------|
            | RAM (window 0) |
            |                |
        8000|----------------|
            | ROM (banked)   |
            | *Cartridge     |
        4000|----------------|
            | ROM (fixed)    |
            |                |
        0000|----------------|

    * cartridge lives in banks 10 onward, see below

        Banked rom area (4000-7fff) bankswitching
        Bankswitching is achieved by writing to I/O port 0 (mirrored on 1-7)
    Bank       ROM_REGION        Contents
    0          0x00000 - 0x03fff System ROM page 0
    1          0x04000 - 0x07fff System ROM page 1
    2          0x08000 - 0x0bfff System ROM page 2
        ... etc ...
    E          0x38000 - 0x38fff System ROM page E
    F          0x3c000 - 0x3ffff System ROM page F
       10          0x40000 - 0x43fff Expansion Cartridge page 0 (cart ROM 0x0000-0x3fff)
       11          0x44000 - 0x47fff Expansion Cartridge page 1 (cart ROM 0x4000-0x7fff)
        ... etc ...

        Banked ram area (z80 0x8000-0xbfff window 0 and z80 0xc000-0xffff window 1)
        Bankswitching is achieved by writing to I/O port 8 (mirrored to 9-F), only low nybble
        byte written: 0b****BBAA
        where BB controls ram window 1 and AA controls ram window 0
        hence:
        Write    [window 0]         [window 1]
        0        0x0000-0x3fff      0x0000-0x3fff
        1        0x4000-0x7fff      0x0000-0x3fff
        2        0x8000-0xbfff      0x0000-0x3fff
        3        0xc000-0xffff      0x0000-0x3fff
        4        0x0000-0x3fff      0x4000-0x7fff
        5        0x4000-0x7fff      0x4000-0x7fff
        6        0x8000-0xbfff      0x4000-0x7fff
        7        0xc000-0xffff      0x4000-0x7fff
        8        0x0000-0x3fff      0x8000-0xbfff
        9        0x4000-0x7fff      0x8000-0xbfff
        A        0x8000-0xbfff      0x8000-0xbfff
        B        0xc000-0xffff      0x8000-0xbfff
        C        0x0000-0x3fff      0xc000-0xffff
        D        0x4000-0x7fff      0xc000-0xffff
        E        0x8000-0xbfff      0xc000-0xffff
        F        0xc000-0xffff      0xc000-0xffff

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

/* Core includes */
#include "emu.h"
#include "cpu/z80/z80.h"
#include "audio/socrates.h"
#include "imagedev/cartslot.h"


class socrates_state : public driver_device
{
public:
	enum
	{
		TIMER_CLEAR_SPEECH,
		TIMER_CLEAR_IRQ
	};

	socrates_state(const machine_config &mconfig, device_type type, const char *tag)
		: driver_device(mconfig, type, tag),
		m_maincpu(*this, "maincpu"),
		m_sound(*this, "soc_snd"),
		m_screen(*this, "screen")
		{ }
	required_device<cpu_device> m_maincpu;
	required_device<socrates_snd_device> m_sound;
	required_device<screen_device> m_screen;

	rgb_t m_palette_val[256];

	UINT8 m_data[8];
	UINT8 m_rom_bank;
	UINT8 m_ram_bank;
	UINT16 m_scroll_offset;
	UINT8* m_videoram;
	UINT8 m_kb_latch_low[2];
	UINT8 m_kb_latch_high[2];
	UINT8 m_kb_latch_mouse;
	UINT8 m_kbmcu_rscount; // how many pokes the kbmcu has taken in the last frame
	UINT8 m_io40_latch; // what was last written to speech reg (for open bus)?
	UINT8 m_hblankstate; // are we in hblank?
	UINT8 m_vblankstate; // are we in vblank?
	UINT8 m_speech_running; // is speech synth talking?
	UINT32 m_speech_address; // address in speech space
	UINT8 m_speech_settings; // speech settings (nybble 0: ? externrom ? ?; nybble 1: ? ? ? ?)
	UINT8 m_speech_dummy_read; // have we done a dummy read yet?
	UINT8 m_speech_load_address_count; // number of times load address has happened
	UINT8 m_speech_load_settings_count; // number of times load settings has happened
	DECLARE_READ8_MEMBER(socrates_rom_bank_r);
	DECLARE_WRITE8_MEMBER(socrates_rom_bank_w);
	DECLARE_READ8_MEMBER(socrates_ram_bank_r);
	DECLARE_WRITE8_MEMBER(socrates_ram_bank_w);
	DECLARE_READ8_MEMBER(read_f3);
	DECLARE_WRITE8_MEMBER(kbmcu_strobe);
	DECLARE_READ8_MEMBER(status_and_speech);
	DECLARE_WRITE8_MEMBER(speech_command);
	DECLARE_READ8_MEMBER(socrates_keyboard_low_r);
	DECLARE_READ8_MEMBER(socrates_keyboard_high_r);
	DECLARE_WRITE8_MEMBER(socrates_keyboard_clear);
	DECLARE_WRITE8_MEMBER(reset_speech);
	DECLARE_WRITE8_MEMBER(socrates_scroll_w);
	DECLARE_WRITE8_MEMBER(socrates_sound_w);
	DECLARE_DRIVER_INIT(socrates);
	virtual void machine_reset();
	virtual void video_start();
	DECLARE_PALETTE_INIT(socrates);
	UINT32 screen_update_socrates(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
	INTERRUPT_GEN_MEMBER(assert_irq);
	TIMER_CALLBACK_MEMBER(clear_speech_cb);
	TIMER_CALLBACK_MEMBER(clear_irq_cb);
	void socrates_set_rom_bank();
	void socrates_set_ram_bank();
	void socrates_update_kb();
	void socrates_check_kb_latch();
	rgb_t socrates_create_color(UINT8 color);

protected:
	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr);
};


class iqunlim_state : public socrates_state
{
public:
	iqunlim_state(const machine_config &mconfig, device_type type, const char *tag)
		: socrates_state(mconfig, type, tag),
			m_bank1(*this, "bank1"),
			m_bank2(*this, "bank2"),
			m_bank3(*this, "bank3"),
			m_bank4(*this, "bank4")
		{ }

	required_memory_bank m_bank1;
	required_memory_bank m_bank2;
	required_memory_bank m_bank3;
	required_memory_bank m_bank4;

	UINT32 screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
	DECLARE_WRITE8_MEMBER( colors_w );
	DECLARE_READ8_MEMBER( rombank_r );
	DECLARE_WRITE8_MEMBER( rombank_w );
	DECLARE_READ8_MEMBER( rambank_r );
	DECLARE_WRITE8_MEMBER( rambank_w );
	DECLARE_READ8_MEMBER( keyboard_r );
	DECLARE_WRITE8_MEMBER( keyboard_clear );
	DECLARE_READ8_MEMBER( video_regs_r );
	DECLARE_WRITE8_MEMBER( video_regs_w );
	DECLARE_READ8_MEMBER( status_r );
	DECLARE_INPUT_CHANGED_MEMBER( send_input );

protected:
	virtual void machine_start();
	virtual void machine_reset();
	int get_color(int index, int y);

private:
	UINT8   m_rombank[2];
	UINT8   m_rambank;
	UINT8   m_colors[8];
	UINT8   m_video_regs[4];

	struct
	{
		UINT8   buffer[8];
		int     head;
		int     tail;
	} m_kb_queue;
};

/* Defines */

/* Components */

/* Devices */

void socrates_state::socrates_set_rom_bank(  )
{
	membank( "bank1" )->set_base( memregion("maincpu")->base() + ( m_rom_bank * 0x4000 ));
}

void socrates_state::socrates_set_ram_bank(  )
{
	membank( "bank2" )->set_base( memregion("vram")->base() + ( (m_ram_bank&0x3) * 0x4000 )); // window 0
	membank( "bank3" )->set_base( memregion("vram")->base() + ( ((m_ram_bank&0xC)>>2) * 0x4000 )); // window 1
}

void socrates_state::socrates_update_kb(  )
{
	static const char *const rownames[] = { "keyboard_40", "keyboard_41", "keyboard_42", "keyboard_43", "keyboard_44" };
	int row, keyvalue, powerof2;
	int shift = 0;
	// first check that the kb latch[1] is clear; if it isn't, don't touch it!
	if ((m_kb_latch_low[1] != 0) || (m_kb_latch_high[1] != 1)) return;
	// next check for joypad buttons
	keyvalue = ioport("keyboard_jp")->read();
	if (keyvalue != 0)
	{
		m_kb_latch_low[1] = (keyvalue & 0xFF0)>>4;
		m_kb_latch_high[1] = 0x80 | (keyvalue & 0xF);
		return; // get out of this function; due to the way key priorities work, we're done here.
	}
	// next check for mouse movement.
	// this isn't written yet, so write me please!
	// next check if shift is down
	shift = ioport("keyboard_50")->read();
	// find key low and high byte ok keyboard section
	for (row = 4; row>=0; row--)
	{
		keyvalue = ioport(rownames[row])->read();
		if (keyvalue != 0)
		{
			for (powerof2 = 9; powerof2 >= 0; powerof2--)
			{
				if ((keyvalue&(1<<powerof2)) == (1<<powerof2))
				{
					m_kb_latch_low[1] = (shift?0x50:0x40)+row;
					m_kb_latch_high[1] = (0x80 | powerof2);
					return; // get out of the for loop; due to the way key priorities work, we're done here.
				}
			}
		}
	}
	// no key was pressed... check if shift was hit then?
	if (shift != 0)
	{
		m_kb_latch_low[1] = 0x50;
		m_kb_latch_high[1] = 0x80;
	}
}

void socrates_state::socrates_check_kb_latch(  ) // if kb[1] is full and kb[0] is not, shift [1] to [0] and clear [1]
{
	if (((m_kb_latch_low[1] != 0) || (m_kb_latch_high[1] != 1)) &&
	((m_kb_latch_low[0] == 0) && (m_kb_latch_high[0] == 1)))
	{
		m_kb_latch_low[0] = m_kb_latch_low[1];
		m_kb_latch_low[1] = 0;
		m_kb_latch_high[0] = m_kb_latch_high[1];
		m_kb_latch_high[1] = 1;
	}
}

void socrates_state::machine_reset()
{
	m_rom_bank = 0xF3; // actually set semi-randomly on real console but we need to initialize it somewhere...
	socrates_set_rom_bank();
	m_ram_bank = 0;  // the actual console sets it semi randomly on power up, and the bios cleans it up.
	socrates_set_ram_bank();
	m_kb_latch_low[0] = 0xFF;
	m_kb_latch_high[0] = 0x8F;
	m_kb_latch_low[1] = 0x00;
	m_kb_latch_high[1] = 0x01;
	m_kb_latch_mouse = 0;
	m_kbmcu_rscount = 0;
	m_io40_latch = 0;
	m_hblankstate = 0;
	m_vblankstate = 0;
	m_speech_running = 0;
	m_speech_address = 0;
	m_speech_settings = 0;
	m_speech_dummy_read = 0;
	m_speech_load_address_count = 0;
	m_speech_load_settings_count = 0;
}

void socrates_state::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	switch (id)
	{
	case TIMER_CLEAR_SPEECH:
		clear_speech_cb(ptr, param);
		break;
	case TIMER_CLEAR_IRQ:
		clear_irq_cb(ptr, param);
		break;
	default:
		assert_always(FALSE, "Unknown id in socrates_state::device_timer");
	}
}

DRIVER_INIT_MEMBER(socrates_state,socrates)
{
	UINT8 *gfx = memregion("vram")->base();
	int i;
	/* fill vram with its init powerup bit pattern, so startup has the checkerboard screen */
	for (i = 0; i < 0x10000; i++)
		gfx[i] = (((i&0x1)?0x00:0xFF)^((i&0x100)?0x00:0xff));
// init sound channels to both be on lowest pitch and max volume
	m_maincpu->set_clock_scale(0.45f); /* RAM access waitstates etc. aren't emulated - slow the CPU to compensate */
}

READ8_MEMBER(socrates_state::socrates_rom_bank_r)
{
	return m_rom_bank;
}

WRITE8_MEMBER(socrates_state::socrates_rom_bank_w)
{
	m_rom_bank = data;
	socrates_set_rom_bank();
}

READ8_MEMBER(socrates_state::socrates_ram_bank_r)
{
	return m_ram_bank;
}

WRITE8_MEMBER(socrates_state::socrates_ram_bank_w)
{
	m_ram_bank = data&0xF;
	socrates_set_ram_bank();
}

READ8_MEMBER(socrates_state::read_f3)// used for read-only i/o ports as mame/mess doesn't have a way to set the unmapped area to read as 0xF3
{
	return 0xF3;
}

WRITE8_MEMBER(socrates_state::kbmcu_strobe) // strobe the keyboard MCU
{
	//logerror("0x%04X: kbmcu written with %02X!\n", m_maincpu->pc(), data); //if (m_maincpu->pc() != 0x31D)
	// if two writes happen within one frame, reset the keyboard latches
	m_kbmcu_rscount++;
	if (m_kbmcu_rscount > 1)
	{
		m_kb_latch_low[0] = 0x00;
		m_kb_latch_high[0] = 0x01;
		m_kb_latch_low[1] = 0x00;
		m_kb_latch_high[1] = 0x01;
		m_kb_latch_mouse = 0;
	}
}

READ8_MEMBER(socrates_state::status_and_speech)// read 0x4x, some sort of status reg
{
// bit 7 - speech status: high when speech is playing, low when it is not (or when speech cart is not present)
// bit 6 - unknown, usually set, may involve the writes to 0x30, possibly some sort of fixed-length timer?
// bit 5 - vblank status, high when not in vblank
// bit 4 - hblank status, high when not in hblank
// bit 3 - speech chip bit 3
// bit 2 - speech chip bit 2
// bit 1 - speech chip bit 1
// bit 0 - speech chip bit 0
UINT8 *speechromint = memregion("speechint")->base();
UINT8 *speechromext = memregion("speechext")->base();
	int temp = 0;
	temp |= (m_speech_running)?0x80:0;
	temp |= 0x40; // unknown, possibly IR mcu busy
	temp |= (m_vblankstate)?0:0x20;
	temp |= (m_hblankstate)?0:0x10;
	switch(m_io40_latch&0xF0) // what was last opcode sent?
	{
		case 0x60: case 0xE0:// speech status 'read' register
			if(m_speech_settings&0x04) // external speech roms (outside of speech ic but still in cart) enabled
			{
			logerror("reading external speech rom nybble from nybble address %x (byte address %x)\n",m_speech_address, m_speech_address>>1);
			temp |= ((speechromext[((m_speech_address>>1)&0xffff)]>>((m_speech_address&1)*4))&0xF);
			}
			else
			{
			logerror("reading internal speech rom nybble from nybble address %x (byte address %x)\n",m_speech_address, m_speech_address>>1);
			temp |= ((speechromint[((m_speech_address>>1)&0x1fff)]>>((m_speech_address&1)*4))&0xF);
			}
			if (m_speech_dummy_read == 0) // if we havent done the dummy read yet, do so now
			{
				m_speech_dummy_read++;
			}
			else
			{
				m_speech_address++;
			}
			break;
		default:
			temp |= m_io40_latch&0xF; // read open bus
			break;
	}
	logerror("read from i/o 0x4x of %x\n", temp);
	return temp;
}

TIMER_CALLBACK_MEMBER(socrates_state::clear_speech_cb)
{
	m_speech_running = 0;
	m_speech_load_address_count = 0; // should this be here or in the write functuon subpart which is speak command?
	m_speech_load_settings_count = 0;
}

WRITE8_MEMBER(socrates_state::speech_command) // write 0x4x
{
	/*
	 * 76543210
	 * |||||||\-- SEL0
	 * ||||||\--- SEL1
	 * |||||\---- SEL2
	 * ||||\----- SEL3
	 * |||\------ SEL4
	 * ||\------- SEL5
	 * |\-------- 64UP (if LOW the chip is in 'dumb' mode and can only play 64 fixed phrases; if HIGH the chip is in 'cpu controlled' mode and commands work) (not 100% sure about this but suspect it is correct)
	 * \--------- START (in cpu mode must be toggled from low->high for a cpu command to 'take'; in 'dumb' mode must be toggled low->high to start that 'word')
	 */
	logerror("write to i/o 0x4x of %x\n", data);
/*
// old readback test, probably get rid of this junk:
// 00-0f: readback: 70-7f
// 10-1f: readback: 70-7f
// 20-2f: readback: 70-7f
// 30-3f: readback: 70-7f
// 40-5f: readback: 70-7f
// 50-5f: readback: 70-7f
// 60-6f: readback: ALL 7f
// 70-7f: readback: 50, 71-7f (force vblank?)
// 80-8f: 80 starts speech reads as f0, rest read as 71-7f
// 90-9f: all 70-7f
// a0-af: 70-7f
// b0-bf: 70-7f
// c0-cf: 70-7f
// d0-df: 70-7f
// e0-ef: readback ALL 76
// f0-ff: 70-7f
*/
/* The speech chip is a toshiba tc8802, it is NOT a t6803 since the t6803
   does not have the rom read mode, which the socrates definitely uses! */
/* Commands (tc8802):
SEL 5 4 3 2 1 0
    0 0 n n n n -  ADLD - ADress LoaD - writes one nybble to the address
                          of vsm rom selected (internal or external) starting
                          from the low 4 bits; each subsequent write writes to
                          the next higher 4 bits; resetting the chip resets
                          the position
    0 1 n n n n -  CNDT - CoNDiTion (aka 'setup') - writes one nybble to the
                          setting register, starting from the low 4 bits; the
                          subsequent write will be to the high 4 bits;
                          resetting the chip will reset the position

                          CNDT bits (? are from T6803 datasheet, which could be wrong on the tc8802AF here):
                           * 76543210
                           * |||||||\-- ?bits/frame bit 1 (0 = see bit 2; 1 = 98bits/frame (these may be backwards))
                           * ||||||\--- ?melody mode select if high
                           * |||||\---- speech rom select; 0 is internal 8k mask, 1 is external vsm bus
                           * ||||\----- ?voiced source select (0 = A; 1 = B)
                           * |||\------ ?filter stages (0 = lpc-10; 1 = lpc-8)
                           * ||\------- ?always 0
                           * |\-------- ?frame length (0 = 20ms; 1 = 10ms)
                           * \--------- ?bits/frame bit 2 (if bit 1 is not set: 0 = 56 bits/frame; 1 = 50 bits/frame)
                           *
    1 0 x x x x -  DTRD - DaTa ReaD - reads a nybble from the address as loaded
                          and increments the address by one nybble. The first
                          DTRD command after any other commands is a 'dummy
                          read' which serves to reset the bus direction of the
                          low 4 SEL lines, identical to the way the TMS5100
                          does things. it doesn't affect the bus direction of
                          the high two SEL lines.
    1 1 0 x x x - START - Starts speech at the address as loaded.
    1 1 1 x x x - RESET - Resets the internal chip state (clears shifters and
                          counters) and forces speech to end/silence
                          immediately.
*/
	switch(data&0xF8)
	{
		case 0x80: case 0x88: case 0x90: case 0x98: case 0xA0: case 0xA8: case 0xB0: case 0xB8:
			/* 'dumb' mode speech command: write me: start talking */
			m_speech_running = 1;
			timer_set(attotime::from_seconds(4), TIMER_CLEAR_SPEECH); // hack
			break;
		case 0xC0: case 0xC8: // ADLD: load address to vsm
			m_speech_address |= (((int)data&0xF)<<(m_speech_load_address_count*4))<<1;
			m_speech_load_address_count++;
			logerror("loaded address nybble %X, byte address is currently %5X with %d nybbles loaded\n", data&0xF, m_speech_address>>1, m_speech_load_address_count);
			break;
		case 0xD0: case 0xD8: // CNDT: load settings
			m_speech_settings |= ((data&0xF)<<(m_speech_load_settings_count*4));
			m_speech_load_settings_count++;
			break;
		case 0xE0: case 0xE8: // DTRD: read byte, handled elsewhere
			break;
		case 0xF0: // SPEAK
			m_speech_running = 1;
			timer_set(attotime::from_seconds(4), TIMER_CLEAR_SPEECH); // hack
			break;
		case 0xF8: // RESET
			m_speech_running = 0;
			m_speech_address = 0;
			m_speech_settings = 0;
			m_speech_dummy_read = 0;
			m_speech_load_address_count = 0;
			m_speech_load_settings_count = 0;
			m_io40_latch &= 0x0f; // set last command to 0 to prevent problems
			break;
		default: // 00 through 70 are packets without the write bit set, ignore them
			break;
	}
	m_io40_latch = data;
}

READ8_MEMBER(socrates_state::socrates_keyboard_low_r)// keyboard code low
{
	socrates_update_kb();
	socrates_check_kb_latch();
	return m_kb_latch_low[0];
}

READ8_MEMBER(socrates_state::socrates_keyboard_high_r)// keyboard code high
{
	socrates_update_kb();
	socrates_check_kb_latch();
	return m_kb_latch_high[0];
}

WRITE8_MEMBER(socrates_state::socrates_keyboard_clear)// keyboard latch shift/clear
{
	m_kb_latch_low[0] = m_kb_latch_low[1];
	m_kb_latch_high[0] = m_kb_latch_high[1];
	m_kb_latch_low[1] = 0;
	m_kb_latch_high[1] = 1;
}

WRITE8_MEMBER(socrates_state::reset_speech)// i/o 60: reset speech synth
{
	m_speech_running = 0;
	m_speech_address = 0;
	m_speech_settings = 0;
	m_speech_dummy_read = 0;
	m_speech_load_address_count = 0;
	m_speech_load_settings_count = 0;
	m_io40_latch &= 0x0f; // set last command to 0 to prevent problems
logerror("write to i/o 0x60 of %x\n",data);
}

/* stuff below belongs in video/nc.c */

WRITE8_MEMBER(socrates_state::socrates_scroll_w)
{
	if (offset == 0)
	m_scroll_offset = (m_scroll_offset&0x100) | data;
	else
	m_scroll_offset = (m_scroll_offset&0xFF) | ((data&1)<<8);
}

/* NTSC-based Palette stuff */
// max for I and Q
#define M_I 0.5957
#define M_Q 0.5226
	/* luma amplitudes, measured on scope */
#define LUMAMAX 1.420
#define LUMA_COL_0 0.355, 0.139, 0.205, 0, 0.569, 0.355, 0.419, 0.205, 0.502, 0.288, 0.358, 0.142, 0.720, 0.502, 0.571, 0.358,
#define LUMA_COL_COMMON 0.52, 0.52, 0.52, 0.52, 0.734, 0.734, 0.734, 0.734, 0.667, 0.667, 0.667, 0.667, 0.885, 0.885, 0.885, 0.885,
#define LUMA_COL_2 0.574, 0.6565, 0.625, 0.71, 0.792, 0.87, 0.8425, 0.925, 0.724, 0.8055, 0.7825, 0.865, 0.94275, 1.0225, 0.99555, 1.07525,
#define LUMA_COL_5 0.4585, 0.382, 0.4065, 0.337, 0.6715, 0.5975, 0.6205, 0.5465, 0.6075, 0.531, 0.5555, 0.45, 0.8255, 0.7455, 0.774, 0.6985,
#define LUMA_COL_F 0.690, 0.904, 0.830, 1.053, 0.910, 1.120, 1.053, 1.270, 0.840, 1.053, 0.990, 1.202, 1.053, 1.270, 1.202, 1.420
	/* chroma amplitudes, measured on scope */
#define CHROMAMAX 0.42075
#define CHROMA_COL_COMMON 0.148, 0.3125, 0.26475, 0.42075, 0.148, 0.3125, 0.26475, 0.42075, 0.148, 0.3125, 0.26475, 0.42075, 0.148, 0.3125, 0.26475, 0.42075,
#define CHROMA_COL_2 0.125125, 0.27525, 0.230225, 0.384875, 0.125125, 0.27525, 0.230225, 0.384875, 0.125125, 0.27525, 0.230225, 0.384875, 0.125125, 0.27525, 0.230225, 0.384875,
#define CHROMA_COL_5 0.1235, 0.2695, 0.22625, 0.378, 0.1235, 0.2695, 0.22625, 0.378, 0.1235, 0.2695, 0.22625, 0.378, 0.1235, 0.2695, 0.22625, 0.378,
// gamma: this needs to be messed with... may differ on different systems... attach to slider somehow?
#define GAMMA 1.5

rgb_t socrates_state::socrates_create_color(UINT8 color)
{
	rgb_t composedcolor;
	static const double lumatable[256] = {
	LUMA_COL_0
	LUMA_COL_COMMON
	LUMA_COL_2
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_5
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_COMMON
	LUMA_COL_F
	};
	static const double chromaintensity[256] = {
	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
	CHROMA_COL_COMMON
	CHROMA_COL_2
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_5
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	CHROMA_COL_COMMON
	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	};
	/* chroma colors and phases:
	 0: black-through-grey (0 assumed chroma)
	 1: purple (90 chroma seems correct)
	 2: light blue/green (210 or 240 chroma, 210 seems slightly closer)
	 3: bright blue (150 seems correct)
	 4: green (270 seems correct)
	 5: red (30 seems correct, does have some blue in it)
	 6: orange (0 seems correct, does have some red in it)
	 7: yellow/gold (330 is closest but conflicts with color C, hence 315 seems close, and must have its own delay line separate from the other phases which use a standard 12 phase scheme)
	 8: blue with a hint of green in it (180 seems correct)
	 9: blue-green (210 seems correct)
	 A: forest green (240 seems correct)
	 B: yellow-green (300 seems correct)
	 C: yellow-orange (330 is close but this conflicts with color 7, and is not quite the same; color 7 has more green in it than color C)
	 D: magenta (60 is closest)
	 E: blue-purple (more blue than color 1, 120 is closest)
	 F: grey-through-white (0 assumed chroma)
	*/
	static const double phaseangle[16] = { 0, 90, 220, 150, 270, 40, 0, 315, 180, 210, 240, 300, 330, 60, 120, 0 }; // note: these are guessed, not measured yet!
	int chromaindex = color&0x0F;
	int swappedcolor = ((color&0xf0)>>4)|((color&0x0f)<<4);
	double finalY, finalI, finalQ, finalR, finalG, finalB;
	finalY = (1/LUMAMAX) * lumatable[swappedcolor];
	finalI = (M_I * (cos((phaseangle[chromaindex]/180)*3.141592653589793)))* ((1/CHROMAMAX)*chromaintensity[swappedcolor]);
	finalQ = (M_Q * (sin((phaseangle[chromaindex]/180)*3.141592653589793)))* ((1/CHROMAMAX)*chromaintensity[swappedcolor]);
	if (finalY > 1) finalY = 1; // clamp luma
	/* calculate the R, G and B values here, neato matrix math */
	finalR = (finalY*1)+(finalI*0.9563)+(finalQ*0.6210);
	finalG = (finalY*1)+(finalI*-0.2721)+(finalQ*-0.6474);
	finalB = (finalY*1)+(finalI*-1.1070)+(finalQ*1.7046);
	/* scale/clamp to 0-255 range */
	if (finalR<0) finalR = 0;
	if (finalR>1) finalR = 1;
	if (finalG<0) finalG = 0;
	if (finalG>1) finalG = 1;
	if (finalB<0) finalB = 0;
	if (finalB>1) finalB = 1;
	// gamma correction: 1.0 to GAMMA:
	finalR = pow(finalR, 1/GAMMA)*255;
	finalG = pow(finalG, 1/GAMMA)*255;
	finalB = pow(finalB, 1/GAMMA)*255;
composedcolor = rgb_t((int)finalR,(int)finalG,(int)finalB);
return composedcolor;
}


PALETTE_INIT_MEMBER(socrates_state, socrates)
{
	int i; // iterator
	for (i = 0; i < 256; i++)
	{
		m_palette_val[i] = socrates_create_color(i);
	}
	palette.set_pen_colors(0, m_palette_val, ARRAY_LENGTH(m_palette_val));
}

void socrates_state::video_start()
{
	m_videoram = memregion("vram")->base();
	m_scroll_offset = 0;
}

UINT32 socrates_state::screen_update_socrates(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
	static const UINT8 fixedcolors[8] =
	{
	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0xF7
	};
	int x, y, colidx, color;
	int lineoffset = 0; // if display ever tries to display data at 0xfxxx, offset line displayed by 0x1000
	for (y = 0; y < 228; y++)
	{
		if ((((y+m_scroll_offset)*128)&0xffff) >= 0xf000) lineoffset = 0x1000; // see comment above
		for (x = 0; x < 264; x++)
		{
			if (x < 256)
			{
				colidx = m_videoram[(((y+m_scroll_offset)*128)+(x>>1)+lineoffset)&0xffff];
				if (x&1) colidx >>=4;
				colidx &= 0xF;
				if (colidx > 7) color=m_videoram[0xF000+(colidx<<8)+((y+m_scroll_offset)&0xFF)];
				else color=fixedcolors[colidx];
				bitmap.pix16(y, x) = color;
			}
			else
			{
				colidx = m_videoram[(((y+m_scroll_offset)*128)+(127)+lineoffset)&0xffff];
				colidx >>=4;
				colidx &= 0xF;
				if (colidx > 7) color=m_videoram[0xF000+(colidx<<8)+((y+m_scroll_offset)&0xFF)];
				else color=fixedcolors[colidx];
				bitmap.pix16(y, x) = color;
			}
		}
	}
	return 0;
}

/* below belongs in sound/nc.c */

WRITE8_MEMBER(socrates_state::socrates_sound_w)
{
	switch(offset)
	{
		case 0:
		m_sound->reg0_w(data);
		break;
		case 1:
		m_sound->reg1_w(data);
		break;
		case 2:
		m_sound->reg2_w(data);
		break;
		case 3:
		m_sound->reg3_w(data);
		break;
		case 4: case 5: case 6: case 7: default:
		m_sound->reg4_w(data);
		break;
	}
}



//-----------------------------------------------------------------------------
//
//        IQ Unlimited
//
//-----------------------------------------------------------------------------

int iqunlim_state::get_color(int index, int y)
{
	if (index < 8)
		return m_colors[index];
	else
		return m_videoram[0xf000 + ((index & 0x0f) << 8) + ((m_scroll_offset + y + 1) & 0xff)];
}

UINT32 iqunlim_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
	// bitmap layer
	for (int y=0; y<224; y++)
	{
		if (y >= m_video_regs[0x03])    break;
		for (int x=0; x<128; x++)
		{
			UINT8 data = m_videoram[(m_scroll_offset + y) * 0x80 + x];

			for(int b=0; b<2; b++)
			{
				bitmap.pix16(y, x*2 + b) = get_color(data & 0x0f, y);
				data >>= 4;
			}
		}
	}

	// text layer
	bool mode_80 = m_video_regs[0x02] & 0x02;   // 80 chars mode
	int line_len = mode_80 ? 80 : 40;
	for (int y=0; y<28; y++)
	{
		for (int x=0; x<line_len; x++)
		{
			UINT8 c = m_videoram[0x8400 + (y - 1) * (mode_80 ? 0x80 : 0x40) + x];
			UINT8 *gfx = &m_videoram[0x8000 + (c & 0x7f) * 8];

			for (int cy=0; cy<8; cy++)
			{
				int py = y * 8 + cy;
				if ((m_video_regs[0x02] & 0x01) || py >= m_video_regs[0x03])
				{
					UINT8 col0 = get_color(0x0e, py);
					UINT8 col1 = get_color(0x0f, py);
					UINT8 data = 0;

					if (BIT(m_video_regs[0x02],4) && m_video_regs[0x00] == x && m_video_regs[0x01] == ((y - 1) + (0x400 / (mode_80 ? 0x80 : 0x40)))) // cursor position start at 0x8000
						data = 0xff;
					else if (y > 0 && y < 26)
						data = gfx[cy] ^ (c & 0x80 ? 0xff : 0);

					if (x == 0) bitmap.plot_box(0, py, 8 + line_len*6 + 8, 1, col0);
					for (int cx=0; cx<6; cx++)
					{
						int px = 8 + x*6 + cx;
						bitmap.pix16(py, px) = BIT(data, 7) ? col1 : col0;
						data <<= 1;
					}
				}
			}
		}
	}

	return 0;
}

READ8_MEMBER( iqunlim_state::status_r )
{
	// ---x ----    main battery status
	// --x- ----    backup battery status

	return 0x30;
}

READ8_MEMBER( iqunlim_state::video_regs_r )
{
	return m_video_regs[offset];
}

WRITE8_MEMBER( iqunlim_state::video_regs_w )
{
	if (offset == 2 && ((m_video_regs[offset] ^ data) & 0x02))
	{
		rectangle visarea = m_screen->visible_area();
		visarea.set(0, (data & 0x02 ? 496 : 256) - 1, 0, 224 - 1);
		m_screen->configure(data & 0x02 ? 496 : 256 , 224, visarea, m_screen->frame_period().attoseconds);
	}

	m_video_regs[offset] = data;
}

void iqunlim_state::machine_start()
{
	UINT8 *bios = memregion("bios")->base();
	UINT8 *cart = memregion("cart")->base();
	UINT8 *ram  = memregion("vram")->base();
	m_bank1->configure_entries(0x00, 0x10, bios, 0x4000);
	m_bank1->configure_entries(0x10, 0x10, cart , 0x4000);
	m_bank1->configure_entries(0x20, 0x10, bios + 0x40000, 0x4000);
	m_bank1->configure_entries(0x30, 0x10, cart + 0x40000 , 0x4000);

	m_bank2->configure_entries(0x00, 0x10, bios, 0x4000);
	m_bank2->configure_entries(0x10, 0x10, cart , 0x4000);
	m_bank2->configure_entries(0x20, 0x10, bios + 0x40000, 0x4000);
	m_bank2->configure_entries(0x30, 0x10, cart + 0x40000 , 0x4000);

	m_bank3->configure_entries(0x00, 0x08, ram, 0x4000);
	m_bank4->configure_entries(0x00, 0x08, ram, 0x4000);
}

void iqunlim_state::machine_reset()
{
	socrates_state::machine_reset();

	m_rambank = m_rombank[0] = m_rombank[1] = 0;
	memset(m_colors, 0, 8);
	memset(m_video_regs, 0, 4);
	m_kb_queue.head = m_kb_queue.tail = 0;

	m_bank1->set_entry(0x00);
	m_bank2->set_entry(0x00);
	m_bank3->set_entry(0x00);
	m_bank4->set_entry(0x00);
}

READ8_MEMBER( iqunlim_state::rombank_r )
{
	return m_rombank[offset];
}

WRITE8_MEMBER( iqunlim_state::rombank_w )
{
	memory_bank *bank = offset ? m_bank1 : m_bank2;
	bank->set_entry(data & 0x3f);

	m_rombank[offset] = data;
}

READ8_MEMBER( iqunlim_state::rambank_r )
{
	return m_rambank;
}

WRITE8_MEMBER( iqunlim_state::rambank_w )
{
	m_bank3->set_entry(((data>>2) & 0x0c) | ((data>>0) & 0x03));
	m_bank4->set_entry(((data>>4) & 0x0c) | ((data>>2) & 0x03));
	m_rambank = data;
}

WRITE8_MEMBER( iqunlim_state::colors_w )
{
	m_colors[offset] = data;
}


// IQ Unlimited keyboard MCU simulation

INPUT_CHANGED_MEMBER( iqunlim_state::send_input )
{
	UINT8 data = (UINT8)(FPTR)param;

	if (newval)
	{
		m_kb_queue.buffer[m_kb_queue.tail] = data;
		m_kb_queue.tail = (m_kb_queue.tail + 1) % sizeof(m_kb_queue.buffer);
	}
}

WRITE8_MEMBER( iqunlim_state::keyboard_clear )
{
	if(m_kb_queue.head != m_kb_queue.tail)
		m_kb_queue.head = (m_kb_queue.head + 1) % sizeof(m_kb_queue.buffer);
}

READ8_MEMBER( iqunlim_state::keyboard_r )
{
	UINT8 data = 0;

	switch(offset)
	{
		case 0:
			if(m_kb_queue.head != m_kb_queue.tail)
				data = m_kb_queue.buffer[m_kb_queue.head];
			break;
		case 1:
			data = (m_kb_queue.head != m_kb_queue.tail ? 0x80 : 0) | (ioport("IN0")->read() & 0x7f);
			if (m_screen->vblank()) data |= 0x80;   // FIXME
			break;
	}

	return data;
}


/******************************************************************************
 Address Maps
******************************************************************************/

static ADDRESS_MAP_START(z80_mem, AS_PROGRAM, 8, socrates_state )
	ADDRESS_MAP_UNMAP_HIGH
	AM_RANGE(0x0000, 0x3fff) AM_ROM /* system rom, bank 0 (fixed) */
	AM_RANGE(0x4000, 0x7fff) AM_ROMBANK("bank1") /* banked rom space; system rom is banks 0 through F, cartridge rom is banks 10 onward, usually banks 10 through 17. area past the end of the cartridge, and the whole 10-ff area when no cartridge is inserted, reads as 0xF3 */
	AM_RANGE(0x8000, 0xbfff) AM_RAMBANK("bank2") /* banked ram 'window' 0 */
	AM_RANGE(0xc000, 0xffff) AM_RAMBANK("bank3") /* banked ram 'window' 1 */
ADDRESS_MAP_END

static ADDRESS_MAP_START(z80_io, AS_IO, 8, socrates_state )
	ADDRESS_MAP_UNMAP_HIGH
	ADDRESS_MAP_GLOBAL_MASK(0xff)
	AM_RANGE(0x00, 0x00) AM_READWRITE(socrates_rom_bank_r, socrates_rom_bank_w) AM_MIRROR(0x7) /* rom bank select - RW - 8 bits */
	AM_RANGE(0x08, 0x08) AM_READWRITE(socrates_ram_bank_r, socrates_ram_bank_w) AM_MIRROR(0x7) /* ram banks select - RW - 4 low bits; Format: 0b****HHLL where LL controls whether window 0 points at ram area: 0b00: 0x0000-0x3fff; 0b01: 0x4000-0x7fff; 0b10: 0x8000-0xbfff; 0b11: 0xc000-0xffff. HH controls the same thing for window 1 */
	AM_RANGE(0x10, 0x17) AM_READWRITE(read_f3, socrates_sound_w) AM_MIRROR (0x8) /* sound section:
        0x10 - W - frequency control for channel 1 (louder channel) - 01=high pitch, ff=low; time between 1->0/0->1 transitions = (XTAL_21_4772MHz/(512+256) / (freq_reg+1)) (note that this is double the actual frequency since each full low and high squarewave pulse is two transitions)
    0x11 - W - frequency control for channel 2 (softer channel) - 01=high pitch, ff=low; same equation as above
    0x12 - W - 0b***EVVVV enable, volume control for channel 1
    0x13 - W - 0b***EVVVV enable, volume control for channel 2
    0x14-0x17 - 0bE??????? enable, unknown for channel 3; produces well defined dmc waves when bit 7 is set, and one or two other bits
    This may be some sort of debug register for serial-dmc banging out some internal rom from the asic, maybe color data?
    No writes to ram seem to change the waveforms produced, in my limited testing.
    0x80 produces about a very very quiet 1/8 duty cycle wave at 60hz or so
    0xC0 produces a DMC wave read from an unknown address at around 342hz
    0x
    */
	AM_RANGE(0x20, 0x21) AM_READWRITE(read_f3, socrates_scroll_w) AM_MIRROR (0xe) /* graphics section:
    0x20 - W - lsb offset of screen display
    0x21 - W - msb offset of screen display
    resulting screen line is one of 512 total offsets on 128-byte boundaries in the whole 64k ram
    */
	AM_RANGE(0x30, 0x30) AM_READWRITE(read_f3, kbmcu_strobe) AM_MIRROR (0xf) /* resets the keyboard IR decoder MCU */
	AM_RANGE(0x40, 0x40) AM_READWRITE(status_and_speech, speech_command ) AM_MIRROR(0xf) /* reads status register for vblank/hblank/speech, also reads and writes speech module */
	AM_RANGE(0x50, 0x50) AM_READWRITE(socrates_keyboard_low_r, socrates_keyboard_clear) AM_MIRROR(0xE) /* Keyboard keycode low, latched on keypress, can be unlatched by writing anything here */
	AM_RANGE(0x51, 0x51) AM_READWRITE(socrates_keyboard_high_r, socrates_keyboard_clear) AM_MIRROR(0xE) /* Keyboard keycode high, latched as above, unlatches same as above */
	AM_RANGE(0x60, 0x60) AM_READWRITE(read_f3, reset_speech) AM_MIRROR(0xF) /* reset the speech module, or perhaps fire an NMI?  */
	AM_RANGE(0x70, 0xFF) AM_READ(read_f3) // nothing mapped here afaik
ADDRESS_MAP_END

static ADDRESS_MAP_START(iqunlim_mem, AS_PROGRAM, 8, iqunlim_state)
	ADDRESS_MAP_UNMAP_HIGH
	AM_RANGE(0x0000, 0x3fff) AM_ROMBANK("bank1")
	AM_RANGE(0x4000, 0x7fff) AM_ROMBANK("bank2")
	AM_RANGE(0x8000, 0xbfff) AM_RAMBANK("bank3")
	AM_RANGE(0xc000, 0xffff) AM_RAMBANK("bank4")
ADDRESS_MAP_END

static ADDRESS_MAP_START( iqunlim_io , AS_IO, 8, iqunlim_state)
	ADDRESS_MAP_UNMAP_HIGH
	ADDRESS_MAP_GLOBAL_MASK(0xff)
	AM_RANGE(0x00, 0x01) AM_READWRITE(rombank_r, rombank_w) AM_MIRROR(0x06)
	AM_RANGE(0x08, 0x08) AM_READWRITE(rambank_r, rambank_w) AM_MIRROR(0x07)
	AM_RANGE(0x10, 0x17) AM_WRITE(socrates_sound_w) AM_MIRROR (0x08)
	AM_RANGE(0x20, 0x21) AM_WRITE(socrates_scroll_w) AM_MIRROR (0x0e)
	AM_RANGE(0x50, 0x51) AM_READWRITE(keyboard_r, keyboard_clear)
	AM_RANGE(0x70, 0x73) AM_READWRITE(video_regs_r, video_regs_w) AM_MIRROR (0x0c)
	AM_RANGE(0x80, 0x81) AM_WRITENOP // LCD
	AM_RANGE(0xb1, 0xb1) AM_WRITENOP
	AM_RANGE(0xa0, 0xa0) AM_READ(status_r) AM_MIRROR(0x0f)
	AM_RANGE(0xe0, 0xe7) AM_WRITE(colors_w) AM_MIRROR(0x08)
ADDRESS_MAP_END



/******************************************************************************
 Input Ports
******************************************************************************/

/* socrates keyboard codes:
keycode low
|   keycode high
|   |   key name
00  01  No key pressed
// pads on the sides of the kb; this acts like a giant bitfield, both dpads/buttons can send data at once
00  81  left dpad right
00  82  left dpad up
00  84  left dpad left
00  88  left dpad down
01  80  right dpad down
02  80  right dpad left
04  80  right dpad up
08  80  right dpad right
10  80  left red button
20  80  right red button
// top row (right to left)
44  82  ENTER
44  83  MENU
44  84  ANSWER
44  85  HELP
44  86  ERASE
44  87  divide_sign
44  88  multiply_sign
44  89  minus_sign
44  80  plus_sign
//second row (right to left)
43  81  0
43  82  9
43  83  8
43  84  7
43  85  6
43  86  5
43  87  4
43  88  3
43  89  2
43  80  1
// third row (right to left)
42  82  I/La
42  83  H/So
42  84  G/Fa
42  85  F/Mi
42  86  E/Re
42  87  D/Do
42  88  C/Ti.
42  89  B/La.
42  80  A/So.
42  81  hyphen/period
// fourth row (right to left)
41  81  S
41  82  R
41  83  Q/NEW
41  84  P/PLAY
41  85  O/PAUSE
41  86  N/Fa`
41  87  M/Mi`
41  88  L/Re`
41  89  K/Do`
41  80  J/Ti
// fifth row (right to left)
40  82  SPACE
40  83  Z
40  84  Y
40  85  X
40  86  W
40  87  V
40  88  U
40  89  T
50  80  SHIFT
// socrates mouse pad (separate from keyboard)
8x  8y  mouse movement
x: down = 1 (small) through 7 (large), up = 8 (small) through F (large)
y: right = 1 (small) through 7 (large), left = 8 (small) through F (large)
90  80  right click
A0  80  left click
B0  80  both buttons click
90  81  right click (mouse movement in queue, will be in regs after next latch clear)
A0  81  left click (mouse movement in queue, will be in regs after next latch clear)
B0  81  both buttons click (mouse movement in queue, will be in regs after next latch clear)
// socrates touch pad
// unknown yet, but probably uses the 60/70/c0/d0/e0/f0 low reg vals
*/
static INPUT_PORTS_START( socrates )

	PORT_START("keyboard_jp") // joypad keys
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_6_PAD) PORT_CHAR(UCHAR_MAMEKEY(6_PAD)) PORT_NAME("Left D-pad Right") // 00 81
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_8_PAD) PORT_CHAR(UCHAR_MAMEKEY(8_PAD)) PORT_NAME("Left D-pad Up") // 00 82
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_4_PAD) PORT_CHAR(UCHAR_MAMEKEY(4_PAD)) PORT_NAME("Left D-pad Left") // 00 84
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_2_PAD) PORT_CHAR(UCHAR_MAMEKEY(2_PAD)) PORT_NAME("Left D-pad Down") // 00 88
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_DOWN) PORT_CHAR(UCHAR_MAMEKEY(DOWN)) PORT_NAME("Right D-pad Down") // 01 80
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_LEFT) PORT_CHAR(UCHAR_MAMEKEY(LEFT)) PORT_NAME("Right D-pad Left") // 02 80
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_UP) PORT_CHAR(UCHAR_MAMEKEY(UP)) PORT_NAME("Right D-pad Up") // 04 80
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_RIGHT) PORT_CHAR(UCHAR_MAMEKEY(RIGHT)) PORT_NAME("Right D-pad Right") // 08 80
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER_PAD) PORT_CHAR(UCHAR_MAMEKEY(ENTER_PAD)) PORT_NAME("Left D-pad Button") // 10 80
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_RALT) PORT_CHAR(UCHAR_MAMEKEY(RALT)) PORT_NAME("Right D-pad Button") // 20 80
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)
	/* alt w/left and right keypad keys swapped
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_RIGHT) PORT_CHAR(UCHAR_MAMEKEY(RIGHT)) PORT_NAME("Left D-pad Right") // 00 81
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_UP) PORT_CHAR(UCHAR_MAMEKEY(UP)) PORT_NAME("Left D-pad Up") // 00 82
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_LEFT) PORT_CHAR(UCHAR_MAMEKEY(LEFT)) PORT_NAME("Left D-pad Left") // 00 84
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_DOWN) PORT_CHAR(UCHAR_MAMEKEY(DOWN)) PORT_NAME("Left D-pad Down") // 00 88
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_2_PAD) PORT_CHAR(UCHAR_MAMEKEY(2_PAD)) PORT_NAME("Right D-pad Down") // 01 80
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_4_PAD) PORT_CHAR(UCHAR_MAMEKEY(4_PAD)) PORT_NAME("Right D-pad Left") // 02 80
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_8_PAD) PORT_CHAR(UCHAR_MAMEKEY(8_PAD)) PORT_NAME("Right D-pad Up") // 04 80
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_6_PAD) PORT_CHAR(UCHAR_MAMEKEY(6_PAD)) PORT_NAME("Right D-pad Right") // 08 80
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_RALT) PORT_CHAR(UCHAR_MAMEKEY(RALT)) PORT_NAME("Left D-pad Button") // 10 80
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER_PAD) PORT_CHAR(UCHAR_MAMEKEY(ENTER_PAD)) PORT_NAME("Right D-pad Button") // 20 80
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)
	*/

	PORT_START("keyboard_50") // lowest 'row' (technically the shift key is on the 5th row but it has its own keycode)
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_LSHIFT) PORT_CODE(KEYCODE_RSHIFT) PORT_CHAR(UCHAR_SHIFT_1) PORT_NAME("SHIFT") // 5x xx
	PORT_BIT(0xfffffffe, IP_ACTIVE_HIGH, IPT_UNUSED)

	PORT_START("keyboard_40") // 5th row
	PORT_BIT(0x00000003, IP_ACTIVE_HIGH, IPT_UNUSED) // 40 80 and 40 81
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_SPACE) PORT_CHAR(' ') PORT_NAME("SPACE") // 40 82
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_Z) PORT_CHAR('Z') PORT_NAME("Z") // 40 83
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_Y) PORT_CHAR('Y') PORT_NAME("Y") // 40 84
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_X) PORT_CHAR('X') PORT_NAME("X") // 40 85
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_W) PORT_CHAR('W') PORT_NAME("W") // 40 86
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_V) PORT_CHAR('V') PORT_NAME("V") // 40 87
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_U) PORT_CHAR('U') PORT_NAME("U") // 40 88
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_T) PORT_CHAR('T') PORT_NAME("T") // 40 89
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)

	PORT_START("keyboard_41") // 4th row
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_J) PORT_CHAR('J') PORT_NAME("J/Ti") // 41 80
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_S) PORT_CHAR('S') PORT_NAME("S") // 41 81
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_R) PORT_CHAR('R') PORT_NAME("R") // 41 82
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_Q) PORT_CHAR('Q') PORT_NAME("Q/NEW") // 41 83
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_P) PORT_CHAR('P') PORT_NAME("P/PLAY") // 41 84
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_O) PORT_CHAR('O') PORT_NAME("O/PAUSE") // 41 85
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_N) PORT_CHAR('N') PORT_NAME("N/Fa'") // 41 86
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_M) PORT_CHAR('M') PORT_NAME("M/Mi'") // 41 87
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_L) PORT_CHAR('L') PORT_NAME("L/Re'") // 41 88
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_K) PORT_CHAR('K') PORT_NAME("K/Do'") // 41 89
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)

	PORT_START("keyboard_42") // 3rd row
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_A) PORT_CHAR('A') PORT_NAME("A/So.") // 42 80
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_STOP) PORT_CHAR('.') PORT_CHAR('-') PORT_NAME("-/.") // 42 81
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_I) PORT_CHAR('I') PORT_NAME("I/La") // 42 82
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_H) PORT_CHAR('H') PORT_NAME("H/So") // 42 83
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_G) PORT_CHAR('G') PORT_NAME("G/Fa") // 42 84
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_F) PORT_CHAR('F') PORT_NAME("F/Mi") // 42 85
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_E) PORT_CHAR('E') PORT_NAME("E/Re") // 42 86
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_D) PORT_CHAR('D') PORT_NAME("D/Do") // 42 87
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_C) PORT_CHAR('C') PORT_NAME("C/Ti.") // 42 88
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_B) PORT_CHAR('B') PORT_NAME("B/La.") // 42 89
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)

	PORT_START("keyboard_43") // 2nd row
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_1) PORT_CHAR('1') PORT_NAME("1") // 43 80
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_0) PORT_CHAR('0') PORT_NAME("0") // 43 81
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_9) PORT_CHAR('9') PORT_NAME("9") // 43 82
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_8) PORT_CHAR('8') PORT_NAME("8") // 43 83
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_7) PORT_CHAR('7') PORT_NAME("7") // 43 84
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_6) PORT_CHAR('6') PORT_NAME("6") // 43 85
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_5) PORT_CHAR('5') PORT_NAME("5") // 43 86
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_4) PORT_CHAR('4') PORT_NAME("4") // 43 87
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_3) PORT_CHAR('3') PORT_NAME("3") // 43 88
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_2) PORT_CHAR('2') PORT_NAME("2") // 43 89
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)

	PORT_START("keyboard_44") // 1st row
	PORT_BIT(0x00000001, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS) PORT_CHAR('+') PORT_NAME("+") // 44 80
	PORT_BIT(0x00000002, IP_ACTIVE_HIGH, IPT_UNUSED) // 44 81
	PORT_BIT(0x00000004, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER) PORT_CHAR(13) PORT_NAME("ENTER") // 44 82
	PORT_BIT(0x00000008, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_HOME) PORT_CHAR(UCHAR_MAMEKEY(HOME)) PORT_NAME("MENU") // 44 83
	PORT_BIT(0x00000010, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_PGUP) PORT_CHAR(UCHAR_MAMEKEY(PGUP)) PORT_NAME("ANSWER") // 44 84
	PORT_BIT(0x00000020, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_PGDN) PORT_CHAR(UCHAR_MAMEKEY(PGDN)) PORT_NAME("HELP") // 44 85
	PORT_BIT(0x00000040, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSPACE) PORT_CHAR(8) PORT_NAME("ERASE") // 44 86
	PORT_BIT(0x00000080, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_SLASH) PORT_CHAR('/') PORT_NAME("/") // 44 87
	PORT_BIT(0x00000100, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_ASTERISK) PORT_CHAR('*') PORT_NAME("*") // 44 88
	PORT_BIT(0x00000200, IP_ACTIVE_HIGH, IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS) PORT_CHAR('-') PORT_NAME("-") // 44 89
	PORT_BIT(0xfffffc00, IP_ACTIVE_HIGH, IPT_UNUSED)

	// mouse goes here
INPUT_PORTS_END


static INPUT_PORTS_START( iqunlimz )
	PORT_START( "IN0" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_LSHIFT )  PORT_CODE( KEYCODE_RSHIFT )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_LCONTROL )  PORT_CODE( KEYCODE_RCONTROL )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_LALT )  PORT_CODE( KEYCODE_RALT )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_CAPSLOCK )
	PORT_BIT( 0xf0, IP_ACTIVE_HIGH, IPT_UNUSED )

	PORT_START( "IN1" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_N ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x10 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_M ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x11 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_COMMA ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x12 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_B ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x13 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_C ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x14 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_Z ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x15 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_V ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x16 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_X ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x17 )

	PORT_START( "IN2" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x20 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_2_PAD ) PORT_CODE( KEYCODE_DOWN ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x21 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_5_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x22 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_DEL_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x23 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_SLASH_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x24 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_8_PAD ) PORT_CODE( KEYCODE_UP ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x25 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_ASTERISK ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x26 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_7_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x27 )

	PORT_START( "IN3" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x30 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x31 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x32 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x33 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_F1 ) PORT_NAME( "Help" ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x34 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_9 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x35 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_BACKSPACE ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x36 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_0 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x37 )

	PORT_START( "IN4" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_H ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x40 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_J ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x41 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_K ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x42 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_G ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x43 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_D ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x44 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_A ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x45 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_F ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x46 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_S ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x47 )

	PORT_START( "IN5" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x50 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x51 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x52 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x53 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_EQUALS ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x54 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_O ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x55 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_NUMLOCK ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x56 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_P ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x57 )

	PORT_START( "IN6" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_Y ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x60 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_U ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x61 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_I ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x62 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_T ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x63 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_E ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x64 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_Q ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x65 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_R ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x66 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_W ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x67 )

	PORT_START( "IN7" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_MINUS ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x70 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_SLASH ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x71 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x72 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_STOP ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x73 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_QUOTE ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x74 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_L ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x75 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_ENTER ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x76 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_COLON ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x77 )

	PORT_START( "IN8" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_6 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x80 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_7 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x81 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_8 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x82 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_5 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x83 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_3 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x84 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_1 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x85 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_4 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x86 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_2 ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x87 )

	PORT_START( "IN9" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_4_PAD ) PORT_CODE( KEYCODE_LEFT ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x90 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_3_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x91 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_6_PAD ) PORT_CODE( KEYCODE_RIGHT ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x92 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_PLUS_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x93 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_0_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x94 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_9_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x95 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_MINUS_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x96 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_1_PAD ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0x97 )

	PORT_START( "INA" )
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa0 )
	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa1 )
	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa2 )
	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_UNUSED ) // PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa3 )
	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_F2 ) PORT_NAME("Answer") PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa4 )
	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_ESC ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa5 )
	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_SPACE ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa6 )
	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE( KEYCODE_TAB ) PORT_CHANGED_MEMBER( DEVICE_SELF, iqunlim_state, send_input, 0xa7 )
INPUT_PORTS_END

/******************************************************************************
 Machine Drivers
******************************************************************************/
TIMER_CALLBACK_MEMBER(socrates_state::clear_irq_cb)
{
	m_maincpu->set_input_line(0, CLEAR_LINE);
	m_vblankstate = 0;
}

INTERRUPT_GEN_MEMBER(socrates_state::assert_irq)
{
	device.execute().set_input_line(0, ASSERT_LINE);
	timer_set(downcast<cpu_device *>(&device)->cycles_to_attotime(44), TIMER_CLEAR_IRQ);
// 44 is a complete and total guess, need to properly measure how many clocks/microseconds the int line is high for.
	m_vblankstate = 1;
	m_kbmcu_rscount = 0; // clear the mcu poke count
}

static MACHINE_CONFIG_START( socrates, socrates_state )
	/* basic machine hardware */
	MCFG_CPU_ADD("maincpu", Z80, XTAL_21_4772MHz/6)  /* Toshiba TMPZ84C00AP @ 3.579545 MHz, verified, xtal is divided by 6 */
	MCFG_CPU_PROGRAM_MAP(z80_mem)
	MCFG_CPU_IO_MAP(z80_io)
	MCFG_QUANTUM_TIME(attotime::from_hz(60))
	MCFG_CPU_VBLANK_INT_DRIVER("screen", socrates_state,  assert_irq)
	//MCFG_MACHINE_START_OVERRIDE(socrates_state,socrates)

	/* video hardware */
	MCFG_SCREEN_ADD("screen", RASTER)
	MCFG_SCREEN_REFRESH_RATE(60)
	MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
	MCFG_SCREEN_SIZE(264, 228) // technically the screen size is 256x228 but super painter abuses what I suspect is a hardware bug to display repeated pixels of the very last pixel beyond this horizontal space, well into hblank
	MCFG_SCREEN_VISIBLE_AREA(0, 263, 0, 219) // the last few rows are usually cut off by the screen bottom but are indeed displayed if you mess with v-hold
	MCFG_SCREEN_UPDATE_DRIVER(socrates_state, screen_update_socrates)
	MCFG_SCREEN_PALETTE("palette")

	MCFG_PALETTE_ADD("palette", 256)
	MCFG_PALETTE_INIT_OWNER(socrates_state, socrates)

	/* sound hardware */
	MCFG_SPEAKER_STANDARD_MONO("mono")
	MCFG_SOUND_ADD("soc_snd", SOCRATES_SOUND, XTAL_21_4772MHz/(512+256)) // this is correct, as strange as it sounds.
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.25)

	MCFG_CARTSLOT_ADD("cart")
	MCFG_CARTSLOT_EXTENSION_LIST("bin")
	MCFG_CARTSLOT_NOT_MANDATORY
	MCFG_CARTSLOT_INTERFACE("socrates_cart")

	/* Software lists */
	MCFG_SOFTWARE_LIST_ADD("cart_list", "socrates")
MACHINE_CONFIG_END

static MACHINE_CONFIG_START( socrates_pal, socrates_state )
	/* basic machine hardware */
	MCFG_CPU_ADD("maincpu", Z80, XTAL_26_601712MHz/6)  /* Toshiba TMPZ84C00AP @ 4.433 MHz? /6 or 7 or 8? TODO: verify divider!*/
	MCFG_CPU_PROGRAM_MAP(z80_mem)
	MCFG_CPU_IO_MAP(z80_io)
	MCFG_QUANTUM_TIME(attotime::from_hz(50))
	MCFG_CPU_VBLANK_INT_DRIVER("screen", socrates_state,  assert_irq)
	//MCFG_MACHINE_START_OVERRIDE(socrates_state,socrates)

	/* video hardware */
	MCFG_SCREEN_ADD("screen", RASTER)
	MCFG_SCREEN_REFRESH_RATE(50)
	MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
	MCFG_SCREEN_SIZE(264, 238) // technically the screen size is 256x228 but super painter abuses what I suspect is a hardware bug to display repeated pixels of the very last pixel beyond this horizontal space, well into hblank
	MCFG_SCREEN_VISIBLE_AREA(0, 263, 0, 229) // the last few rows are usually cut off by the screen bottom but are indeed displayed if you mess with v-hold
	MCFG_SCREEN_UPDATE_DRIVER(socrates_state, screen_update_socrates)
	MCFG_SCREEN_PALETTE("palette")

	MCFG_PALETTE_ADD("palette", 256)
	MCFG_PALETTE_INIT_OWNER(socrates_state, socrates)

	/* sound hardware */
	MCFG_SPEAKER_STANDARD_MONO("mono")
	MCFG_SOUND_ADD("soc_snd", SOCRATES_SOUND, XTAL_26_601712MHz/(512+256)) // TODO: verify divider for pal mode
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.25)

	MCFG_CARTSLOT_ADD("cart")
	MCFG_CARTSLOT_EXTENSION_LIST("bin")
	MCFG_CARTSLOT_NOT_MANDATORY
	MCFG_CARTSLOT_INTERFACE("socrates_cart")

	/* Software lists */
	MCFG_SOFTWARE_LIST_ADD("cart_list", "socrates")
MACHINE_CONFIG_END

/* This doesn't work for some reason.
static MACHINE_CONFIG_DERIVED( socrates_pal, socrates )
    MCFG_CPU_REPLACE("maincpu", Z80, XTAL_26_601712MHz/8)
    MCFG_SCREEN_REPLACE("screen", RASTER)
    MCFG_SCREEN_REFRESH_RATE(50)
    MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500))
    MCFG_SCREEN_SIZE(264, 256) // technically the screen size is 256x228 but super painter abuses what I suspect is a hardware bug to display repeated pixels of the very last pixel beyond this horizontal space, well into hblank
    MCFG_SCREEN_VISIBLE_AREA(0, 263, 0, 256) // the last few rows are usually cut off by the screen bottom but are indeed displayed if you mess with v-hold
    MCFG_SCREEN_UPDATE_DRIVER(socrates_state, screen_update_socrates)
    MCFG_SOUND_REPLACE("soc_snd", SOCRATES_SOUND, XTAL_26_601712MHz/(512+256)) // this is correct, as strange as it sounds.
    MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.25)
MACHINE_CONFIG_END
*/

static MACHINE_CONFIG_START( iqunlimz, iqunlim_state )
	/* basic machine hardware */
	MCFG_CPU_ADD("maincpu", Z80, XTAL_4MHz) /* not accurate */
	MCFG_CPU_PROGRAM_MAP(iqunlim_mem)
	MCFG_CPU_IO_MAP(iqunlim_io)
	MCFG_CPU_VBLANK_INT_DRIVER("screen", iqunlim_state,  assert_irq)

	/* video hardware */
	MCFG_SCREEN_ADD("screen", RASTER)
	MCFG_SCREEN_REFRESH_RATE(60)
	MCFG_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
	MCFG_SCREEN_UPDATE_DRIVER(iqunlim_state, screen_update)
	MCFG_SCREEN_SIZE(256, 224)
	MCFG_SCREEN_VISIBLE_AREA(0, 256-1, 0, 224-1)
	MCFG_SCREEN_PALETTE("palette")

	MCFG_PALETTE_ADD("palette", 256)
	MCFG_PALETTE_INIT_OWNER(socrates_state, socrates)

	/* sound hardware */
	MCFG_SPEAKER_STANDARD_MONO("mono")
	MCFG_SOUND_ADD("soc_snd", SOCRATES_SOUND, XTAL_21_4772MHz/(512+256))
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.25)

	MCFG_CARTSLOT_ADD("cart")
	MCFG_CARTSLOT_EXTENSION_LIST("bin")
	MCFG_CARTSLOT_NOT_MANDATORY
MACHINE_CONFIG_END

/******************************************************************************
 ROM Definitions
******************************************************************************/

ROM_START(socrates)
	ROM_REGION(0x400000, "maincpu", ROMREGION_ERASEVAL(0xF3)) /* can technically address 4mb of rom via bankswitching; open bus area reads as 0xF3 */
	/* Socrates US NTSC */
	/* all cart roms are 28 pin 23c1000/tc531000 128Kx8 roms */
	/* cart port pinout:
	(looking into end of disk-shaped cartridge with label/top side pointing to the right)
	A15 -> 19  18 -- VCC
	A14 -> 20  17 <- A16
	A13 -> 21  16 <- A12
	 A8 -> 22  15 <- A7
	 A9 -> 23  14 <- A6
	A11 -> 24  13 <- A5
	 A3 -> 25  12 <- A4
	 A2 -> 26  11 <- A10
	 D7 <- 27  10 <- A1
	 D6 <- 28  9 <- A0
	 D5 <- 29  8 -> D0
	 D4 <- 30  7 -> D1
	 D3 <- 31  6 -> D2
	  ? ?? 32  5 ?? ?
	A17 -> 33  4 ?? ?
	  ? ?? 34  3 ?? ?
	/CE -> 35  2 ?? ?
	GND -- 36  1 -- GND
	Note that a17 goes to what would be pin 2 on a rom chip if a 32 pin rom were installed, which is not the case. (pins 1, 31 and 32 would be tied to vcc)
	It is likely that at least one of the 6 unknown lines is R/W from the z80, and another may be phi1/m1/clock etc to allow for ram to live in cart space

	Cartridge check procedure by socrates is, after screen init and check for speech synth,
	bankswitch to bank 0x10 (i.e. first 0x4000 of cart appears at 4000-7fff in z80 space),
	do following tests; if any tests fail, jump to 0x0015 (socrates main menu)
	* read 0x7ff0(0x3ff0 in cart rom) and compare to 0xAA
	* read 0x7ff1(0x3ff1 in cart rom) and compare to 0x55
	* read 0x7ff2(0x3ff2 in cart rom) and compare to 0xE7
	* read 0x7ff3(0x3ff3 in cart rom) and compare to 0x18
	if all tests passed, jump to 0x4000 (0x0000 in cart rom)
	*/
	ROM_LOAD("27-00817-000-000.u1", 0x00000, 0x40000, CRC(80f5aa20) SHA1(4fd1ff7f78b5dd2582d5de6f30633e4e4f34ca8f)) // Label: "(Vtech) 27-00817-000-000 // (C)1987 VIDEO TECHNOLOGY // 8811 D"
	ROM_CART_LOAD( "cart", 0x40000, 0x20000, 0 )

	ROM_REGION(0x10000, "vram", ROMREGION_ERASEFF) /* fill with ff, driver_init changes this to the 'correct' startup pattern */

	ROM_REGION(0x800, "kbmcu", ROMREGION_ERASEFF)
	ROM_LOAD("tmp42c40p1844.u2", 0x000, 0x200, NO_DUMP) /* keyboard IR decoder MCU */

	/* english speech cart has a green QC sticker */
	ROM_REGION(0x2000, "speechint", ROMREGION_ERASE00) // speech data inside of the speech chip; fill with 00, if no speech cart is present socrates will see this
	ROM_LOAD_OPTIONAL("speech_eng_internal.bin", 0x0000, 0x2000, CRC(edc1fb3f) SHA1(78b4631fc3b1c038e14911047f9edd6c4e8bae58)) // 8k on the speech chip itself

	ROM_REGION(0x10000, "speechext", ROMREGION_ERASE00) // speech serial modules outside of the speech chip but still on speech cart
	ROM_LOAD_OPTIONAL("speech_eng_vsm1.bin", 0x0000, 0x4000, CRC(888e3ddd) SHA1(33AF6A21BA6D826071C9D48557B1C9012752570B)) // 16k in serial rom
	ROM_LOAD_OPTIONAL("speech_eng_vsm2.bin", 0x4000, 0x4000, CRC(de4ac89d) SHA1(3DFA853B02DF756A9B72DEF94A39310992EE11C7)) // 16k in serial rom
	ROM_LOAD_OPTIONAL("speech_eng_vsm3.bin", 0x8000, 0x4000, CRC(972384aa) SHA1(FFCB1D633CA6BFFC7F481EC505DA447E5B847F16)) // 16k in serial rom
	ROM_FILL(0xC000, 0x4000, 0xff) // last vsm isn't present, FF fill
ROM_END

ROM_START(socratfc)
	ROM_REGION(0x80000, "maincpu", ROMREGION_ERASEVAL(0xF3))
	/* Socrates SAITOUT (French Canadian) NTSC */
	ROM_LOAD("27-00884-001-000.u1", 0x00000, 0x40000, CRC(042d9d21) SHA1(9ffc67b2721683b2536727d0592798fbc4d061cb)) // Label: "(Vtech) 27-00884-001-000 // (C)1988 VIDEO TECHNOLOGY // 8911 D"
	ROM_CART_LOAD( "cart", 0x40000, 0x20000, 0 )

	ROM_REGION(0x10000, "vram", ROMREGION_ERASEFF) /* fill with ff, driver_init changes this to the 'correct' startup pattern */

	ROM_REGION(0x800, "kbmcu", ROMREGION_ERASEFF)
	ROM_LOAD("tmp42c40p1844.u2", 0x000, 0x200, NO_DUMP) /* keyboard IR decoder MCU */

	ROM_REGION(0x2000, "speechint", ROMREGION_ERASE00) // speech data inside of the speech chip; fill with 00, if no speech cart is present socrates will see this
	ROM_LOAD_OPTIONAL("speech_fra_internal.bin", 0x0000, 0x2000, NO_DUMP)

	ROM_REGION(0x10000, "speechext", ROMREGION_ERASE00) // speech serial modules outside of the speech chip but still on speech cart
	ROM_LOAD_OPTIONAL("speech_fra_vsm1.bin", 0x0000, 0x4000, NO_DUMP) // 16k in serial rom
	ROM_LOAD_OPTIONAL("speech_fra_vsm2.bin", 0x4000, 0x4000, NO_DUMP) // 16k in serial rom
	ROM_LOAD_OPTIONAL("speech_fra_vsm3.bin", 0x8000, 0x4000, NO_DUMP) // 16k in serial rom
	ROM_FILL(0xC000, 0x4000, 0xff) // last vsm isn't present, FF fill
ROM_END

ROM_START(profweis)
	ROM_REGION(0x80000, "maincpu", ROMREGION_ERASEVAL(0xF3))
	/* Yeno Professor Weiss-Alles (German PAL) */
	ROM_SYSTEM_BIOS(0, "89", "1989")
	ROMX_LOAD("lh53216d.u1", 0x00000, 0x40000, CRC(6e801762) SHA1(b80574a3abacf18133dacb9d3a8d9e2916730423), ROM_BIOS(1)) // Label: "(Vtech) LH53216D // (C)1989 VIDEO TECHNOLOGY // 9119 D"
	ROM_SYSTEM_BIOS(1, "88", "1988")
	ROMX_LOAD("27-00885-001-000.u1", 0x00000, 0x40000, CRC(fcaf8850) SHA1(a99011ee6a1ef63461c00d062278951252f117db), ROM_BIOS(2)) // Label: "(Vtech) 27-00884-001-000 // (C)1988 VIDEO TECHNOLOGY // 8911 D"
	ROM_CART_LOAD( "cart", 0x40000, 0x20000, 0 )

	ROM_REGION(0x10000, "vram", ROMREGION_ERASEFF) /* fill with ff, driver_init changes this to the 'correct' startup pattern */

	ROM_REGION(0x800, "kbmcu", ROMREGION_ERASEFF)
	ROM_LOAD("tmp42c40p1844.u2", 0x000, 0x200, NO_DUMP) /* keyboard IR decoder MCU */

	ROM_REGION(0x2000, "speechint", ROMREGION_ERASE00) // speech data inside of the speech chip; fill with 00, if no speech cart is present socrates will see this
	ROM_LOAD_OPTIONAL("speech_ger_internal.bin", 0x0000, 0x2000, CRC(5ff0fdc6) SHA1(8ef128561a846762a20e3fe9513a4a22aaadc7f6))

	ROM_REGION(0x10000, "speechext", ROMREGION_ERASE00) // speech serial modules outside of the speech chip but still on speech cart
	ROM_LOAD_OPTIONAL("speech_ger_vsm1.bin", 0x0000, 0x4000, CRC(a979a00b) SHA1(0290844619dbdf336757003aaab3ffd0a75b7ee9)) // 16k in serial rom
	ROM_FILL(0x4000, 0xc000, 0xff) // last 3 vsms aren't present, FF fill
ROM_END

ROM_START( iqunlimz )
	ROM_REGION( 0x80000, "bios", 0 )
	ROM_LOAD( "vtech.bin", 0x000000, 0x080000, CRC(f100c8a7) SHA1(6ad2a8accae2dd5c5c46ae953eef33cdd1ea3cf9) )

	ROM_REGION( 0x80000, "cart", ROMREGION_ERASEFF )
	ROM_CART_LOAD( "cart", 0, 0x80000, 0 )

	ROM_REGION( 0x20000, "vram", ROMREGION_ERASE )
ROM_END


/******************************************************************************
 Drivers
******************************************************************************/

/*    YEAR  NAME        PARENT      COMPAT  MACHINE     INPUT   INIT       COMPANY                     FULLNAME                            FLAGS */
COMP( 1988, socrates,   0,          0,      socrates,   socrates, socrates_state, socrates, "Video Technology",        "Socrates Educational Video System", GAME_NOT_WORKING | GAME_IMPERFECT_SOUND ) // English NTSC, no title copyright
COMP( 1988, socratfc,   socrates,   0,      socrates,   socrates, socrates_state, socrates, "Video Technology",        "Socrates SAITOUT", GAME_NOT_WORKING | GAME_IMPERFECT_SOUND ) // French Canandian NTSC, 1988 title copyright
COMP( 1988, profweis,   socrates,   0,      socrates_pal,   socrates, socrates_state, socrates, "Video Technology/Yeno",        "Professor Weiss-Alles", GAME_NOT_WORKING | GAME_IMPERFECT_SOUND ) // German PAL, 1988 title copyright
// Yeno Professeur Saitout goes here (french SECAM)
// ? goes here (spanish PAL)

COMP( 1991, iqunlimz, 0,       0,     iqunlimz,  iqunlimz, driver_device, 0,  "Video Technology", "IQ Unlimited (Z80)", GAME_NOT_WORKING | GAME_NO_SOUND)