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path: root/src/mame/drivers/cxgz80.cpp
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// license:BSD-3-Clause
// copyright-holders:hap
// thanks-to:Berger
/******************************************************************************

    CXG* generic Z80 based chess computer driver
    *later known as CXG Newcrest Technology Ltd.

    NOTE: MAME doesn't include a generalized implementation for boardpieces yet,
    greatly affecting user playability of emulated electronic board games.
    As workaround for the chess games, use an external chess GUI on the side,
    such as Arena(in editmode).

    TODO:
    - nothing

******************************************************************************

Chess 2001:
- Zilog Z8400APS @ 4 MHz (8MHz XTAL)
- 2KB RAM HM6116, 16KB ROM D27128D
- TTL, piezo, 8*8+9 LEDs, magnetic sensors

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

#include "emu.h"
#include "cpu/z80/z80.h"
#include "machine/timer.h"
#include "sound/dac.h"
#include "sound/volt_reg.h"
#include "speaker.h"

// internal artwork
#include "cxg_ch2001.lh" // clickable


class cxgz80_state : public driver_device
{
public:
	cxgz80_state(const machine_config &mconfig, device_type type, const char *tag)
		: driver_device(mconfig, type, tag),
		m_maincpu(*this, "maincpu"),
		m_dac(*this, "dac"),
		m_speaker_off_timer(*this, "speaker_off"),
		m_inp_matrix(*this, "IN.%u", 0),
		m_out_x(*this, "%u.%u", 0U, 0U),
		m_out_a(*this, "%u.a", 0U),
		m_out_digit(*this, "digit%u", 0U),
		m_display_wait(33),
		m_display_maxy(1),
		m_display_maxx(0)
	{ }

	// devices/pointers
	required_device<cpu_device> m_maincpu;
	required_device<dac_bit_interface> m_dac;
	required_device<timer_device> m_speaker_off_timer;
	optional_ioport_array<10> m_inp_matrix; // max 10
	output_finder<0x20, 0x20> m_out_x;
	output_finder<0x20> m_out_a;
	output_finder<0x20> m_out_digit;

	TIMER_DEVICE_CALLBACK_MEMBER(irq_on) { m_maincpu->set_input_line(INPUT_LINE_IRQ0, ASSERT_LINE); }
	TIMER_DEVICE_CALLBACK_MEMBER(irq_off) { m_maincpu->set_input_line(INPUT_LINE_IRQ0, CLEAR_LINE); }

	// misc common
	u16 m_inp_mux;                  // multiplexed keypad mask
	u16 m_led_select;
	u16 m_led_data;

	u16 read_inputs(int columns);

	// display common
	int m_display_wait;             // led/lamp off-delay in milliseconds (default 33ms)
	int m_display_maxy;             // display matrix number of rows
	int m_display_maxx;             // display matrix number of columns (max 31 for now)

	u32 m_display_state[0x20];      // display matrix rows data (last bit is used for always-on)
	u16 m_display_segmask[0x20];    // if not 0, display matrix row is a digit, mask indicates connected segments
	u8 m_display_decay[0x20][0x20]; // (internal use)

	TIMER_DEVICE_CALLBACK_MEMBER(display_decay_tick);
	void display_update();
	void set_display_size(int maxx, int maxy);
	void display_matrix(int maxx, int maxy, u32 setx, u32 sety, bool update = true);

	// Chess 2001
	TIMER_DEVICE_CALLBACK_MEMBER(speaker_off_callback);
	DECLARE_WRITE8_MEMBER(ch2001_speaker_on_w);
	DECLARE_WRITE8_MEMBER(ch2001_leds_w);
	DECLARE_READ8_MEMBER(ch2001_input_r);
	void ch2001_map(address_map &map);
	void ch2001(machine_config &config);

protected:
	virtual void machine_start() override;
	virtual void machine_reset() override;
};


// machine start/reset

void cxgz80_state::machine_start()
{
	// resolve handlers
	m_out_x.resolve();
	m_out_a.resolve();
	m_out_digit.resolve();

	// zerofill
	memset(m_display_state, 0, sizeof(m_display_state));
	memset(m_display_decay, 0, sizeof(m_display_decay));
	memset(m_display_segmask, 0, sizeof(m_display_segmask));

	m_inp_mux = 0;
	m_led_select = 0;
	m_led_data = 0;

	// register for savestates
	save_item(NAME(m_display_maxy));
	save_item(NAME(m_display_maxx));
	save_item(NAME(m_display_wait));

	save_item(NAME(m_display_state));
	save_item(NAME(m_display_decay));
	save_item(NAME(m_display_segmask));

	save_item(NAME(m_inp_mux));
	save_item(NAME(m_led_select));
	save_item(NAME(m_led_data));
}

void cxgz80_state::machine_reset()
{
}



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

  Helper Functions

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

// The device may strobe the outputs very fast, it is unnoticeable to the user.
// To prevent flickering here, we need to simulate a decay.

void cxgz80_state::display_update()
{
	for (int y = 0; y < m_display_maxy; y++)
	{
		u32 active_state = 0;

		for (int x = 0; x <= m_display_maxx; x++)
		{
			// turn on powered segments
			if (m_display_state[y] >> x & 1)
				m_display_decay[y][x] = m_display_wait;

			// determine active state
			u32 ds = (m_display_decay[y][x] != 0) ? 1 : 0;
			active_state |= (ds << x);

			// output to y.x, or y.a when always-on
			if (x != m_display_maxx)
				m_out_x[y][x] = ds;
			else
				m_out_a[y] = ds;
		}

		// output to digity
		if (m_display_segmask[y] != 0)
			m_out_digit[y] = active_state & m_display_segmask[y];
	}
}

TIMER_DEVICE_CALLBACK_MEMBER(cxgz80_state::display_decay_tick)
{
	// slowly turn off unpowered segments
	for (int y = 0; y < m_display_maxy; y++)
		for (int x = 0; x <= m_display_maxx; x++)
			if (m_display_decay[y][x] != 0)
				m_display_decay[y][x]--;

	display_update();
}

void cxgz80_state::set_display_size(int maxx, int maxy)
{
	m_display_maxx = maxx;
	m_display_maxy = maxy;
}

void cxgz80_state::display_matrix(int maxx, int maxy, u32 setx, u32 sety, bool update)
{
	set_display_size(maxx, maxy);

	// update current state
	u32 mask = (1 << maxx) - 1;
	for (int y = 0; y < maxy; y++)
		m_display_state[y] = (sety >> y & 1) ? ((setx & mask) | (1 << maxx)) : 0;

	if (update)
		display_update();
}


// generic input handlers

u16 cxgz80_state::read_inputs(int columns)
{
	u16 ret = 0;

	// read selected input rows
	for (int i = 0; i < columns; i++)
		if (m_inp_mux >> i & 1)
			ret |= m_inp_matrix[i]->read();

	return ret;
}



// Devices, I/O

/******************************************************************************
    Chess 2001
******************************************************************************/

// TTL

TIMER_DEVICE_CALLBACK_MEMBER(cxgz80_state::speaker_off_callback)
{
	m_dac->write(0);
}

WRITE8_MEMBER(cxgz80_state::ch2001_speaker_on_w)
{
	// 74ls109 clock pulse to speaker
	m_dac->write(1);
	m_speaker_off_timer->adjust(attotime::from_usec(200)); // not accurate
}

WRITE8_MEMBER(cxgz80_state::ch2001_leds_w)
{
	// d0-d7: 74ls273 (WR to CLK)
	// 74ls273 Q1-Q4: 74ls145 A-D
	// 74ls145 0-9: input mux/led select
	m_inp_mux = 1 << (data & 0xf) & 0x3ff;

	// 74ls273 Q5-Q8: MC14028 A-D
	// MC14028 Q0-Q7: led data, Q8,Q9: N/C
	u8 led_data = 1 << (data >> 4 & 0xf) & 0xff;
	display_matrix(8, 10, led_data, m_inp_mux);
}

READ8_MEMBER(cxgz80_state::ch2001_input_r)
{
	// d0-d7: multiplexed inputs
	return ~read_inputs(10);
}



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

// Chess 2001

void cxgz80_state::ch2001_map(address_map &map)
{
	map(0x0000, 0x3fff).rom();
	map(0x4000, 0x47ff).mirror(0x3800).ram();
	map(0x8000, 0x8000).mirror(0x3fff).rw(this, FUNC(cxgz80_state::ch2001_input_r), FUNC(cxgz80_state::ch2001_leds_w));
	map(0xc000, 0xc000).mirror(0x3fff).w(this, FUNC(cxgz80_state::ch2001_speaker_on_w));
}



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

static INPUT_PORTS_START( cb_magnets )
	PORT_START("IN.0")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.1")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.2")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.3")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.4")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.5")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.6")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")

	PORT_START("IN.7")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_TOGGLE PORT_NAME("Board Sensor")
INPUT_PORTS_END


static INPUT_PORTS_START( ch2001 )
	PORT_INCLUDE( cb_magnets )

	PORT_START("IN.8")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_T) PORT_NAME("Black")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_2) PORT_NAME("King")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_3) PORT_NAME("Queen")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_4) PORT_NAME("Rook")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_W) PORT_NAME("Bishop")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_E) PORT_NAME("Knight")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_R) PORT_NAME("Pawn")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_5) PORT_NAME("White")

	PORT_START("IN.9")
	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_1) PORT_NAME("Set up")
	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_Q) PORT_NAME("New Game")
	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_U) PORT_NAME("Take Back")
	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_Y) PORT_NAME("Forward")
	PORT_BIT(0x10, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_6) PORT_NAME("Hint")
	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_I) PORT_NAME("Move")
	PORT_BIT(0x40, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_8) PORT_NAME("Level")
	PORT_BIT(0x80, IP_ACTIVE_HIGH, IPT_KEYPAD) PORT_CODE(KEYCODE_7) PORT_NAME("Sound")
INPUT_PORTS_END



/******************************************************************************
    Machine Drivers
******************************************************************************/

MACHINE_CONFIG_START(cxgz80_state::ch2001)

	/* basic machine hardware */
	MCFG_DEVICE_ADD("maincpu", Z80, 8_MHz_XTAL/2)
	MCFG_DEVICE_PROGRAM_MAP(ch2001_map)
	MCFG_TIMER_DRIVER_ADD_PERIODIC("irq_on", cxgz80_state, irq_on, attotime::from_hz(484)) // theoretical frequency from 555 timer (22nF, 100K+33K, 1K2), measurement was 568Hz
	MCFG_TIMER_START_DELAY(attotime::from_hz(484) - attotime::from_nsec(18300)) // active for 18.3us
	MCFG_TIMER_DRIVER_ADD_PERIODIC("irq_off", cxgz80_state, irq_off, attotime::from_hz(484))

	MCFG_TIMER_DRIVER_ADD("speaker_off", cxgz80_state, speaker_off_callback)

	MCFG_TIMER_DRIVER_ADD_PERIODIC("display_decay", cxgz80_state, display_decay_tick, attotime::from_msec(1))
	MCFG_DEFAULT_LAYOUT(layout_cxg_ch2001)

	/* sound hardware */
	SPEAKER(config, "speaker").front_center();
	MCFG_DEVICE_ADD("dac", DAC_1BIT, 0) MCFG_SOUND_ROUTE(ALL_OUTPUTS, "speaker", 0.25)
	MCFG_DEVICE_ADD("vref", VOLTAGE_REGULATOR, 0) MCFG_VOLTAGE_REGULATOR_OUTPUT(5.0)
	MCFG_SOUND_ROUTE(0, "dac", 1.0, DAC_VREF_POS_INPUT)
MACHINE_CONFIG_END



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

ROM_START( ch2001 )
	ROM_REGION( 0x10000, "maincpu", 0 )
	ROM_LOAD("ch2001.bin", 0x0000, 0x4000, CRC(b3485c73) SHA1(f405c6f67fe70edf45dcc383a4049ee6bad387a9) ) // D27128D, no label
ROM_END



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

/*    YEAR  NAME    PARENT  COMPAT  MACHINE  INPUT   CLASS         INIT        COMPANY  FULLNAME      FLAGS */
CONS( 1984, ch2001, 0,      0,      ch2001,  ch2001, cxgz80_state, empty_init, "CXG",   "Chess 2001", MACHINE_SUPPORTS_SAVE | MACHINE_CLICKABLE_ARTWORK | MACHINE_IMPERFECT_CONTROLS )