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path: root/src/mame/drivers/beezer.cpp
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// license: BSD-3-Clause
// copyright-holders: Mathis Rosenhauer, Dirk Best
// thanks-to: Jonathan Gevaryahu
/***************************************************************************

    Beezer

    (c) 1982 Tong Electronic

    Notes:
    - To enter test mode, hold down 1P Start and 2P Start, then reset
    - One of the ROMs contains a message that this game was created
      by "Pacific Polytechnical Corporation, Santa Cruz"

    TODO:
    - Improve sound (filters? A reference recording would be nice)
    - Schematics in the sound area seem incomplete, there are
      several unknown connections
    - Watchdog timing (controlled by a 555)
    - Figure out differences between the two sets (test mode isn't
      working in beezer1, instruction screen is different)
    - Verify accuracy of colors

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

#include "emu.h"
#include "cpu/m6809/m6809.h"
#include "machine/input_merger.h"
#include "machine/timer.h"
#include "machine/watchdog.h"
#include "machine/bankdev.h"
#include "machine/6522via.h"
#include "machine/6840ptm.h"
#include "sound/mm5837.h"
#include "sound/dac76.h"
#include "video/resnet.h"
#include "screen.h"
#include "speaker.h"


//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************

class beezer_state : public driver_device
{
public:
	beezer_state(const machine_config &mconfig, device_type type, const char *tag)
		: driver_device(mconfig, type, tag),
		m_maincpu(*this, "maincpu"),
		m_sysbank(*this, "sysbank"),
		m_banked_roms(*this, "banked"),
		m_rombank{ {*this, "rombank_f1"}, {*this, "rombank_f3"}, {*this, "rombank_e1"}, {*this, "rombank_e3"}, {*this, "rombank_e5"}, {*this, "rombank_f5"}, {*this, "rombank_f7"} },
		m_via_system(*this, "via_u6"),
		m_screen(*this, "screen"),
		m_palette(*this, "palette"),
		m_videoram(*this, "videoram"),
		m_audiocpu(*this, "audiocpu"),
		m_via_audio(*this, "via_u18"),
		m_ptm(*this, "ptm"),
		m_dac(*this, "dac"),
		m_timer_count(nullptr),
		m_count(0), m_noise(0),
		m_pbus(0xff), m_x(0), m_y(0), m_z(0)
	{
		m_ch_sign[0] = m_ch_sign[1] = m_ch_sign[2] = m_ch_sign[3] = 0;
		m_dac_data[0] = m_dac_data[1] = m_dac_data[2] = m_dac_data[3] = 0;
	}

	TIMER_DEVICE_CALLBACK_MEMBER(scanline_cb);
	uint32_t screen_update_beezer(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
	DECLARE_PALETTE_INIT(beezer);
	DECLARE_WRITE8_MEMBER(palette_w);
	DECLARE_READ8_MEMBER(line_r);

	DECLARE_WRITE_LINE_MEMBER(noise_w);
	DECLARE_WRITE8_MEMBER(dac_w);
	DECLARE_READ8_MEMBER(via_audio_pa_r);
	DECLARE_WRITE8_MEMBER(via_audio_pa_w);
	DECLARE_WRITE8_MEMBER(via_audio_pb_w);
	DECLARE_WRITE_LINE_MEMBER(ptm_o1_w);
	DECLARE_WRITE_LINE_MEMBER(ptm_o2_w);
	DECLARE_WRITE_LINE_MEMBER(ptm_o3_w);
	DECLARE_WRITE_LINE_MEMBER(dmod_clr_w);
	DECLARE_WRITE_LINE_MEMBER(dmod_data_w);

	DECLARE_READ8_MEMBER(via_system_pa_r);
	DECLARE_READ8_MEMBER(via_system_pb_r);
	DECLARE_WRITE8_MEMBER(via_system_pa_w);
	DECLARE_WRITE8_MEMBER(via_system_pb_w);
	DECLARE_WRITE8_MEMBER(bankswitch_w);

	void beezer(machine_config &config);
	void banked_map(address_map &map);
	void main_map(address_map &map);
	void sound_map(address_map &map);
protected:
	virtual void machine_start() override;
	virtual void machine_reset() override;
	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;

private:
	required_device<cpu_device> m_maincpu;
	required_device<address_map_bank_device> m_sysbank;
	required_memory_region m_banked_roms;
	required_memory_bank m_rombank[7];
	required_device<via6522_device> m_via_system;
	required_device<screen_device> m_screen;
	required_device<palette_device> m_palette;
	required_shared_ptr<uint8_t> m_videoram;
	required_device<cpu_device> m_audiocpu;
	required_device<via6522_device> m_via_audio;
	required_device<ptm6840_device> m_ptm;
	required_device<dac76_device> m_dac;

	double m_weights_r[3];
	double m_weights_g[3];
	double m_weights_b[2];

	emu_timer *m_timer_count;

	int m_ch_sign[4];
	uint8_t m_dac_data[4];
	int m_count;
	int m_noise;

	uint8_t m_pbus;
	int m_x, m_y, m_z;
};


//**************************************************************************
//  ADDRESS MAPS
//**************************************************************************

void beezer_state::main_map(address_map &map)
{
	map(0x0000, 0xbfff).ram().share("videoram");
	map(0xc000, 0xcfff).m(m_sysbank, FUNC(address_map_bank_device::amap8));
	map(0xd000, 0xdfff).rom().region("maincpu", 0x0000).w(this, FUNC(beezer_state::bankswitch_w)); // g1
	map(0xe000, 0xefff).rom().region("maincpu", 0x1000); // g3
	map(0xf000, 0xffff).rom().region("maincpu", 0x2000); // g5
}

void beezer_state::banked_map(address_map &map)
{
	map(0x0600, 0x0600).mirror(0x1ff).w("watchdog", FUNC(watchdog_timer_device::reset_w));
	map(0x0800, 0x080f).mirror(0x1f0).w(this, FUNC(beezer_state::palette_w));
	map(0x0a00, 0x0a00).mirror(0x1ff).r(this, FUNC(beezer_state::line_r));
	map(0x0e00, 0x0e0f).mirror(0x1f0).rw("via_u6", FUNC(via6522_device::read), FUNC(via6522_device::write));
	map(0x1000, 0x1fff).bankr("rombank_f1");
	map(0x2000, 0x2fff).bankr("rombank_f3");
	map(0x3000, 0x3fff).bankr("rombank_e1");
	map(0x4000, 0x4fff).bankr("rombank_e3");
	map(0x5000, 0x5fff).bankr("rombank_e5");
	map(0x6000, 0x6fff).bankr("rombank_f5");
	map(0x7000, 0x7fff).bankr("rombank_f7");
}

void beezer_state::sound_map(address_map &map)
{
	map(0x0000, 0x07ff).ram(); // 0d
	map(0x0800, 0x0fff).ram(); // 2d, optional (can be rom)
	map(0x1000, 0x1007).mirror(0x07f8).rw(m_ptm, FUNC(ptm6840_device::read), FUNC(ptm6840_device::write));
	map(0x1800, 0x180f).mirror(0x07f0).rw(m_via_audio, FUNC(via6522_device::read), FUNC(via6522_device::write));
	map(0x8000, 0x8003).mirror(0x1ffc).w(this, FUNC(beezer_state::dac_w));
//  AM_RANGE(0xa000, 0xbfff) AM_ROM // 2d (can be ram, unpopulated)
//  AM_RANGE(0xc000, 0xdfff) AM_ROM // 4d (unpopulated)
	map(0xe000, 0xffff).rom().region("audiocpu", 0); // 6d
}


//**************************************************************************
//  INPUTS
//**************************************************************************

static INPUT_PORTS_START( beezer )
	PORT_START("IN0")
	PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_TILT )
	PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_COIN1 )
	PORT_BIT( 0x04, IP_ACTIVE_LOW, IPT_START2 )
	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_START1 )
	PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_UNUSED )
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_UNUSED )
	PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_UNUSED )
	PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNUSED )

	PORT_START("IN1")
	PORT_BIT( 0x0f, 0x00, IPT_TRACKBALL_X ) PORT_SENSITIVITY(20) PORT_KEYDELTA(10) PORT_REVERSE
	PORT_START("IN2")
	PORT_BIT( 0x0f, 0x00, IPT_TRACKBALL_Y ) PORT_SENSITIVITY(20) PORT_KEYDELTA(10) PORT_REVERSE

	// DSWA isn't populated on the board and is pulled to 0xff with a resistor pack
	PORT_START("DSWA")
	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )

	PORT_START("DSWB")
	PORT_DIPNAME( 0x03, 0x03, DEF_STR( Coinage ) )      PORT_DIPLOCATION("SWB:1,2")
	PORT_DIPSETTING(    0x02, DEF_STR( 2C_1C ) )
	PORT_DIPSETTING(    0x03, DEF_STR( 1C_1C ) )
	PORT_DIPSETTING(    0x00, DEF_STR( Free_Play ) )
	PORT_DIPNAME( 0x04, 0x00, DEF_STR( Lives ) )        PORT_DIPLOCATION("SWB:3")
	PORT_DIPSETTING(    0x04, "3" )
	PORT_DIPSETTING(    0x00, "4" )
	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Demo_Sounds ) )  PORT_DIPLOCATION("SWB:4")
	PORT_DIPSETTING(    0x00, DEF_STR( Off ) )
	PORT_DIPSETTING(    0x08, DEF_STR( On ) )
	PORT_DIPNAME( 0x30, 0x10, DEF_STR( Bonus_Life ) )   PORT_DIPLOCATION("SWB:5,6")
	PORT_DIPSETTING(    0x20, "30000" )
	PORT_DIPSETTING(    0x10, "60000" )
	PORT_DIPSETTING(    0x00, "90000" )
	PORT_DIPSETTING(    0x30, DEF_STR( No ) )
	PORT_DIPNAME( 0xc0, 0xc0, DEF_STR( Difficulty ) )   PORT_DIPLOCATION("SWB:7,8")
	PORT_DIPSETTING(    0xc0, DEF_STR( Easy ) )
	PORT_DIPSETTING(    0x80, DEF_STR( Medium ) )
	PORT_DIPSETTING(    0x40, DEF_STR( Hard ) )
	PORT_DIPSETTING(    0x00, DEF_STR( Hardest ) )
INPUT_PORTS_END


//**************************************************************************
//  VIDEO EMULATION
//**************************************************************************

TIMER_DEVICE_CALLBACK_MEMBER( beezer_state::scanline_cb )
{
	// TDISP, each 32 lines
	m_via_system->write_ca2((param & 32) ? 1 : 0);

	// actually unused by the game (points to a tight loop)
	if (param == 240)
		m_maincpu->set_input_line(M6809_FIRQ_LINE, ASSERT_LINE);
	else
		m_maincpu->set_input_line(M6809_FIRQ_LINE, CLEAR_LINE);
}

uint32_t beezer_state::screen_update_beezer(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
	for (int y = cliprect.min_y; y <= cliprect.max_y; y++)
	{
		for (int x = cliprect.min_x; x <= cliprect.max_x; x += 2)
		{
			bitmap.pix16(y, x + 1) = m_videoram[0x80 * x + y] & 0x0f;
			bitmap.pix16(y, x + 0) = m_videoram[0x80 * x + y] >> 4;
		}
	}

	return 0;
}

PALETTE_INIT_MEMBER(beezer_state, beezer)
{
	const int resistances_rg[3] = { 1200, 560, 330 };
	const int resistances_b[2]  = { 560, 330 };

	// calculate coefficients for later use
	compute_resistor_weights(0, 255, -1.0,
		3, resistances_rg, m_weights_r, 680, 150,
		3, resistances_rg, m_weights_g, 680, 150,
		2, resistances_b,  m_weights_b, 680, 150);
}

WRITE8_MEMBER( beezer_state::palette_w )
{
	int r = combine_3_weights(m_weights_r, BIT(data, 0), BIT(data, 1), BIT(data, 2));
	int g = combine_3_weights(m_weights_g, BIT(data, 3), BIT(data, 4), BIT(data, 5));
	int b = combine_2_weights(m_weights_b, BIT(data, 6), BIT(data, 7));

	m_palette->set_pen_color(offset, rgb_t(r, g, b));
}

READ8_MEMBER( beezer_state::line_r )
{
	// d2 to d7 connected to hex buffer u34
	return m_screen->vpos() & 0xfc;
}


//**************************************************************************
//  AUDIO
//**************************************************************************

void beezer_state::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	// channel multiplexer at u52
	int ch = m_count++ & 3;

	m_dac->update();

	m_dac->b1_w(BIT(m_dac_data[ch], 6));
	m_dac->b2_w(BIT(m_dac_data[ch], 5));
	m_dac->b3_w(BIT(m_dac_data[ch], 4));
	m_dac->b4_w(BIT(m_dac_data[ch], 3));
	m_dac->b5_w(BIT(m_dac_data[ch], 2));
	m_dac->b6_w(BIT(m_dac_data[ch], 1));
	m_dac->b7_w(BIT(m_dac_data[ch], 0));

	m_dac->sb_w(m_ch_sign[ch] ^ BIT(m_dac_data[ch], 7));
}

WRITE_LINE_MEMBER( beezer_state::noise_w )
{
	m_noise = state;
	m_via_audio->write_pb6(m_noise);
}

WRITE8_MEMBER( beezer_state::dac_w )
{
	m_dac_data[offset] = data;
}

READ8_MEMBER( beezer_state::via_audio_pa_r )
{
	return m_pbus;
}

WRITE8_MEMBER( beezer_state::via_audio_pa_w )
{
	m_pbus = data;
}

WRITE8_MEMBER( beezer_state::via_audio_pb_w )
{
	// bit 0 - dmod disable
	// bit 1 - fm or am
	// bit 2 - am
	// bit 3 - fmsel0
	// bit 4 - fmsel1
	// -- above bits not handled and only partially visible on the schematic

	// bit 7 - noise gate on rising edge to ptm c1
	if (m_ch_sign[0] == 0 && (BIT(data, 7) == 1))
		m_ptm->set_c1(m_noise);

	m_ch_sign[0] = BIT(data, 7);
}

WRITE_LINE_MEMBER( beezer_state::ptm_o1_w )
{
	m_ch_sign[1] = state;
}

WRITE_LINE_MEMBER( beezer_state::ptm_o2_w )
{
	// on rising edge, enable noise input to ptm c3
	if (m_ch_sign[2] == 0 && state == 1)
		m_ptm->set_c3(m_noise);

	m_ch_sign[2] = state;
}

WRITE_LINE_MEMBER( beezer_state::ptm_o3_w )
{
	m_ch_sign[3] = state;
}

WRITE_LINE_MEMBER( beezer_state::dmod_clr_w )
{
	// schematics don't show where this is connected
}

WRITE_LINE_MEMBER( beezer_state::dmod_data_w )
{
	// schematics don't show where this is connected
}


//**************************************************************************
//  MACHINE EMULATION
//**************************************************************************

READ8_MEMBER( beezer_state::via_system_pa_r )
{
	uint8_t data = 0;

	data |= 1 << 4; // N/C
	data |= m_z << 5;
	data |= m_y << 6;
	data |= m_x << 7;

	return data;
}

WRITE8_MEMBER(beezer_state::via_system_pa_w)
{
	// bit 3, audio cpu reset line
	m_audiocpu->set_input_line(INPUT_LINE_RESET, BIT(data, 3) ? CLEAR_LINE : ASSERT_LINE);

	// bit 2, enable for ls139
	if (BIT(data, 2) == 0)
	{
		// bit 0-1, input selection
		switch (data & 0x03)
		{
		case 0:
			m_pbus = ioport("IN0")->read();
			break;
		case 1:
			m_pbus = ioport("IN1")->read() | (ioport("IN2")->read() << 4);
			break;
		case 2:
			m_pbus = ioport("DSWB")->read();
			break;
		case 3:
			m_pbus = ioport("DSWA")->read();
			break;
		}
	}
}

READ8_MEMBER( beezer_state::via_system_pb_r )
{
	return m_pbus;
}

WRITE8_MEMBER( beezer_state::via_system_pb_w )
{
	m_pbus = data;
}

WRITE8_MEMBER( beezer_state::bankswitch_w )
{
	m_x = BIT(data, 3);
	m_y = BIT(data, 4);
	m_z = BIT(data, 5);

	m_sysbank->set_bank(data & 0x07);

	for (int i = 0; i < 7; i++)
		m_rombank[i]->set_entry(m_x);
}

void beezer_state::machine_start()
{
	// configure rom banks
	for (int i = 0; i < 7; i++)
		m_rombank[i]->configure_entries(0, 2, m_banked_roms->base() + (i * 0x2000), 0x1000);

	// allocate timers
	m_timer_count = timer_alloc(0);

	// register for state saving
	save_pointer(NAME(m_ch_sign), 4);
	save_pointer(NAME(m_dac_data), 4);
	save_item(NAME(m_count));
	save_item(NAME(m_noise));
	save_item(NAME(m_pbus));
	save_item(NAME(m_x));
	save_item(NAME(m_y));
	save_item(NAME(m_z));
}

void beezer_state::machine_reset()
{
	m_pbus = 0xff;

	// initialize memory banks
	bankswitch_w(machine().dummy_space(), 0, 0);

	// start timer
	m_timer_count->adjust(attotime::zero, 0, attotime::from_hz((XTAL(4'000'000) / 4) / 16));
}


//**************************************************************************
//  MACHINE DEFINTIONS
//**************************************************************************

MACHINE_CONFIG_START(beezer_state::beezer)
	// basic machine hardware
	MCFG_DEVICE_ADD("maincpu", MC6809, XTAL(12'000'000) / 3)
	MCFG_DEVICE_PROGRAM_MAP(main_map)

	MCFG_DEVICE_ADD("sysbank", ADDRESS_MAP_BANK, 0)
	MCFG_DEVICE_PROGRAM_MAP(banked_map)
	MCFG_ADDRESS_MAP_BANK_ENDIANNESS(ENDIANNESS_BIG)
	MCFG_ADDRESS_MAP_BANK_DATA_WIDTH(8)
	MCFG_ADDRESS_MAP_BANK_ADDR_WIDTH(15)
	MCFG_ADDRESS_MAP_BANK_STRIDE(0x1000)

	MCFG_TIMER_DRIVER_ADD_SCANLINE("scantimer", beezer_state, scanline_cb, "screen", 0, 1)

	MCFG_DEVICE_ADD("via_u6", VIA6522, XTAL(12'000'000) / 12)
	MCFG_VIA6522_READPA_HANDLER(READ8(*this, beezer_state, via_system_pa_r))
	MCFG_VIA6522_READPB_HANDLER(READ8(*this, beezer_state, via_system_pb_r))
	MCFG_VIA6522_WRITEPA_HANDLER(WRITE8(*this, beezer_state, via_system_pa_w))
	MCFG_VIA6522_WRITEPB_HANDLER(WRITE8(*this, beezer_state, via_system_pb_w))
	MCFG_VIA6522_CB1_HANDLER(WRITELINE("via_u18", via6522_device, write_ca2))
	MCFG_VIA6522_CB2_HANDLER(WRITELINE("via_u18", via6522_device, write_ca1))
	MCFG_VIA6522_IRQ_HANDLER(INPUTLINE("maincpu", M6809_IRQ_LINE))

	MCFG_WATCHDOG_ADD("watchdog")

	// 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(384, 256)
	MCFG_SCREEN_VISIBLE_AREA(16, 304-1, 0, 240-1) // 288 x 240, correct?
	MCFG_SCREEN_UPDATE_DRIVER(beezer_state, screen_update_beezer)
	MCFG_SCREEN_PALETTE("palette")

	MCFG_PALETTE_ADD("palette", 16)
	MCFG_PALETTE_INIT_OWNER(beezer_state, beezer)

	// sound hardware
	MCFG_DEVICE_ADD("audiocpu", MC6809, XTAL(4'000'000))
	MCFG_DEVICE_PROGRAM_MAP(sound_map)

	MCFG_INPUT_MERGER_ANY_HIGH("audio_irqs")
	MCFG_INPUT_MERGER_OUTPUT_HANDLER(INPUTLINE("audiocpu", M6809_IRQ_LINE))

	MCFG_DEVICE_ADD("via_u18", VIA6522, XTAL(4'000'000) / 4)
	MCFG_VIA6522_READPA_HANDLER(READ8(*this, beezer_state, via_audio_pa_r))
	MCFG_VIA6522_WRITEPA_HANDLER(WRITE8(*this, beezer_state, via_audio_pa_w))
	MCFG_VIA6522_WRITEPB_HANDLER(WRITE8(*this, beezer_state, via_audio_pb_w))
	MCFG_VIA6522_CA2_HANDLER(WRITELINE("via_u6", via6522_device, write_cb1))
	MCFG_VIA6522_CB1_HANDLER(WRITELINE(*this, beezer_state, dmod_clr_w))
	MCFG_VIA6522_CB2_HANDLER(WRITELINE(*this, beezer_state, dmod_data_w))
	MCFG_VIA6522_IRQ_HANDLER(WRITELINE("audio_irqs", input_merger_device, in_w<0>))

	MCFG_DEVICE_ADD("ptm", PTM6840, XTAL(4'000'000) / 4)
	MCFG_PTM6840_O1_CB(WRITELINE(*this, beezer_state, ptm_o1_w))
	MCFG_PTM6840_O2_CB(WRITELINE(*this, beezer_state, ptm_o2_w))
	MCFG_PTM6840_O3_CB(WRITELINE(*this, beezer_state, ptm_o3_w))
	MCFG_PTM6840_IRQ_CB(WRITELINE("audio_irqs", input_merger_device, in_w<1>))
	// schematics show an input labeled VCO to channel 2, but the source is unknown

	MCFG_MM5837_ADD("noise")
	MCFG_MM5837_VDD(12)
	MCFG_MM5837_OUTPUT_CB(WRITELINE(*this, beezer_state, noise_w))

	SPEAKER(config, "speaker").front_center();
	MCFG_DEVICE_ADD("dac", DAC76, 0)
	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "speaker", 1.0)
MACHINE_CONFIG_END


//**************************************************************************
//  ROM DEFINITIONS
//**************************************************************************

ROM_START( beezer )
	ROM_REGION(0xc000, "maincpu", 0)
	ROM_LOAD("g1", 0x0000, 0x1000, CRC(3467a0ec) SHA1(0b094a9bf772b101acd26cf09009c67dd4785ed2))
	ROM_LOAD("g3", 0x1000, 0x1000, CRC(9950cdf2) SHA1(b2b59cc1080357de6ba297392881d626157df809))
	ROM_LOAD("g5", 0x2000, 0x1000, CRC(a4b09879) SHA1(69739dd1d3c88ee6ab310ca3c71b3b50d8ec618f))

	// rom type can be either 2732 or 2764 in all locations
	ROM_REGION(0xe000, "banked", 0)
	ROM_LOAD("f1", 0x0000, 0x2000, CRC(ce1b0b8b) SHA1(8ed1d793928bb7afa041a4f61e0c2f78b4442f2f))
	ROM_LOAD("f3", 0x2000, 0x2000, CRC(6a11072a) SHA1(9700beaec669849da4d0e39d6dbf0b872d7f1b7f))
	ROM_LOAD("e1", 0x4000, 0x1000, CRC(21e4ca9b) SHA1(4024678a4006614051675858ba65db655931a539))
	ROM_RELOAD(0x5000, 0x1000)
	ROM_LOAD("e3", 0x6000, 0x1000, CRC(a4f735d7) SHA1(110061d1c63a331384729951f93a31e62744d0d7))
	ROM_RELOAD(0x7000, 0x1000)
	ROM_LOAD("e5", 0x8000, 0x1000, CRC(0485575b) SHA1(c3be070541459fad4da4a71604883b2f3043374a))
	ROM_RELOAD(0x9000, 0x1000)
	ROM_LOAD("f5", 0xa000, 0x1000, CRC(4b11f572) SHA1(4f283c98a7f1bcf534921b4a54cf564335c53e37))
	ROM_RELOAD(0xb000, 0x1000)
	ROM_LOAD("f7", 0xc000, 0x1000, CRC(bef67473) SHA1(5759ceeca0bb677cee97b74f1a1087d53c25463a))
	ROM_RELOAD(0xd000, 0x1000)

	ROM_REGION(0x2000, "audiocpu", 0)
	ROM_LOAD("d7", 0x1000, 0x1000, CRC(23b0782e) SHA1(7751327b84235a2e2700e4bdd21adec205c54f0e))

	ROM_REGION(0x200, "proms", 0)
	ROM_LOAD("d1.cpu", 0x000, 0x100, CRC(8db17a40) SHA1(0e04a4f5f99b302dbbbfda438808d549f8680fe2))
	ROM_LOAD("e1.cpu", 0x100, 0x100, CRC(3c775c5e) SHA1(ac86f45938c0c9d5fec1245bf86718442baf445b))
ROM_END

ROM_START( beezer1 )
	ROM_REGION(0x3000, "maincpu", 0)
	ROM_LOAD("g1.32", 0x0000, 0x1000, CRC(3134cb93) SHA1(7d4a484378b66ccf2fded31885d6dfb2abae9317))
	ROM_LOAD("g3.32", 0x1000, 0x1000, CRC(a3cb2c2d) SHA1(1e17eb0eaf02f86865845a065a5f714fc51aa7d6))
	ROM_LOAD("g5.32", 0x2000, 0x1000, CRC(5e559bf9) SHA1(cd3713f3ed1215ea5c5640474ba6f005242cd093))

	// rom type can be either 2732 or 2764 in all locations
	ROM_REGION(0xe000, "banked", 0)
	ROM_LOAD("f1.64", 0x0000, 0x2000, CRC(b8a78cca) SHA1(4218ef8c4c8e10d7cc47d6de4c4d189ef3c0f0a1))
	ROM_LOAD("f3.32", 0x2000, 0x1000, CRC(bfa023f5) SHA1(56fb15e2db61197e1aec5a5825beff7c788a4ba3))
	ROM_RELOAD(0x3000, 0x1000)
	ROM_LOAD("e1",    0x4000, 0x1000, CRC(21e4ca9b) SHA1(4024678a4006614051675858ba65db655931a539))
	ROM_RELOAD(0x5000, 0x1000)
	ROM_LOAD("e3",    0x6000, 0x1000, CRC(a4f735d7) SHA1(110061d1c63a331384729951f93a31e62744d0d7))
	ROM_RELOAD(0x7000, 0x1000)
	ROM_LOAD("e5",    0x8000, 0x1000, CRC(0485575b) SHA1(c3be070541459fad4da4a71604883b2f3043374a))
	ROM_RELOAD(0x9000, 0x1000)
	ROM_LOAD("f5",    0xa000, 0x1000, CRC(4b11f572) SHA1(4f283c98a7f1bcf534921b4a54cf564335c53e37))
	ROM_RELOAD(0xb000, 0x1000)
	ROM_LOAD("f7",    0xc000, 0x1000, CRC(bef67473) SHA1(5759ceeca0bb677cee97b74f1a1087d53c25463a))
	ROM_RELOAD(0xd000, 0x1000)

	ROM_REGION(0x2000, "audiocpu", 0)
	ROM_LOAD("d7.32", 0x1000, 0x1000, CRC(b11028b5) SHA1(db8958f0bb12e333ce056da3338f1a824dda36e0))

	ROM_REGION(0x200, "proms", 0)
	ROM_LOAD("d1.cpu", 0x000, 0x100, CRC(8db17a40) SHA1(0e04a4f5f99b302dbbbfda438808d549f8680fe2))
	ROM_LOAD("e1.cpu", 0x100, 0x100, CRC(3c775c5e) SHA1(ac86f45938c0c9d5fec1245bf86718442baf445b))
ROM_END


//**************************************************************************
//  SYSTEM DRIVERS
//**************************************************************************

//    YEAR  NAME     PARENT  MACHINE  INPUT   CLASS         INIT        ROTATION  COMPANY            FULLNAME          FLAGS
GAME( 1982, beezer,  0,      beezer,  beezer, beezer_state, empty_init, ROT90,    "Tong Electronic", "Beezer (set 1)", MACHINE_IMPERFECT_SOUND )
GAME( 1982, beezer1, beezer, beezer,  beezer, beezer_state, empty_init, ROT90,    "Tong Electronic", "Beezer (set 2)", MACHINE_IMPERFECT_SOUND )