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

Konami Battlantis Hardware

Supports:
 GX765 - Rack 'em Up/The Hustler (c) 1987 Konami
 GX777 - Battlantis (c) 1987 Konami

Preliminary driver by: Manuel Abadia <manu@teleline.es>

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

#include "driver.h"
#include "cpu/hd6309/hd6309.h"
#include "cpu/z80/z80.h"
#include "video/konamiic.h"
#include "sound/3812intf.h"

/* from video */
WRITE8_HANDLER( battlnts_spritebank_w );
VIDEO_START( battlnts );
VIDEO_UPDATE( battlnts );

static INTERRUPT_GEN( battlnts_interrupt )
{
	if (K007342_is_INT_enabled())
		cpu_set_input_line(device, HD6309_IRQ_LINE, HOLD_LINE);
}

static WRITE8_HANDLER( battlnts_sh_irqtrigger_w )
{
	cpu_set_input_line_and_vector(space->machine->cpu[1], 0, HOLD_LINE, 0xff);
}

static WRITE8_HANDLER( battlnts_bankswitch_w )
{
	UINT8 *RAM = memory_region(space->machine, "maincpu");
	int bankaddress;

	/* bits 6 & 7 = bank number */
	bankaddress = 0x10000 + ((data & 0xc0) >> 6) * 0x4000;
	memory_set_bankptr(space->machine, 1,&RAM[bankaddress]);

	/* bits 4 & 5 = coin counters */
	coin_counter_w(0,data & 0x10);
	coin_counter_w(1,data & 0x20);

	/* other bits unknown */
}

static ADDRESS_MAP_START( battlnts_map, ADDRESS_SPACE_PROGRAM, 8 )
	AM_RANGE(0x0000, 0x1fff) AM_READWRITE(K007342_r, K007342_w)	/* Color RAM + Video RAM */
	AM_RANGE(0x2000, 0x21ff) AM_READWRITE(K007420_r, K007420_w)	/* Sprite RAM */
	AM_RANGE(0x2200, 0x23ff) AM_READWRITE(K007342_scroll_r, K007342_scroll_w)		/* Scroll RAM */
	AM_RANGE(0x2400, 0x24ff) AM_RAM_WRITE(paletteram_xBBBBBGGGGGRRRRR_be_w) AM_BASE(&paletteram)/* palette */
	AM_RANGE(0x2600, 0x2607) AM_WRITE(K007342_vreg_w) 			/* Video Registers */
	AM_RANGE(0x2e00, 0x2e00) AM_READ_PORT("DSW1")
	AM_RANGE(0x2e01, 0x2e01) AM_READ_PORT("P2")
	AM_RANGE(0x2e02, 0x2e02) AM_READ_PORT("P1")
	AM_RANGE(0x2e03, 0x2e03) AM_READ_PORT("DSW3")				/* coinsw, testsw, startsw */
	AM_RANGE(0x2e04, 0x2e04) AM_READ_PORT("DSW2")
	AM_RANGE(0x2e08, 0x2e08) AM_WRITE(battlnts_bankswitch_w)	/* bankswitch control */
	AM_RANGE(0x2e0c, 0x2e0c) AM_WRITE(battlnts_spritebank_w)	/* sprite bank select */
	AM_RANGE(0x2e10, 0x2e10) AM_WRITE(watchdog_reset_w)			/* watchdog reset */
	AM_RANGE(0x2e14, 0x2e14) AM_WRITE(soundlatch_w)				/* sound code # */
	AM_RANGE(0x2e18, 0x2e18) AM_WRITE(battlnts_sh_irqtrigger_w)	/* cause interrupt on audio CPU */
	AM_RANGE(0x4000, 0x7fff) AM_ROMBANK(1)						/* banked ROM */
	AM_RANGE(0x8000, 0xffff) AM_ROM								/* ROM 777e02.bin */
ADDRESS_MAP_END

static ADDRESS_MAP_START( battlnts_sound_map, ADDRESS_SPACE_PROGRAM, 8 )
	AM_RANGE(0x0000, 0x7fff) AM_ROM							/* ROM 777c01.rom */
	AM_RANGE(0x8000, 0x87ff) AM_RAM							/* RAM */
	AM_RANGE(0xa000, 0xa001) AM_DEVREADWRITE("ym1", ym3812_r, ym3812_w)		/* YM3812 (chip 1) */
	AM_RANGE(0xc000, 0xc001) AM_DEVREADWRITE("ym2", ym3812_r, ym3812_w)		/* YM3812 (chip 2) */
	AM_RANGE(0xe000, 0xe000) AM_READ(soundlatch_r)			/* soundlatch_r */
ADDRESS_MAP_END

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

    Input Ports

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

static INPUT_PORTS_START( battlnts )
	PORT_START("DSW1")
	PORT_DIPNAME( 0x0f, 0x0f, DEF_STR( Coin_A ) )		PORT_DIPLOCATION("SW1:1,2,3,4")
	PORT_DIPSETTING(	0x02, DEF_STR( 4C_1C ) )
	PORT_DIPSETTING(	0x05, DEF_STR( 3C_1C ) )
	PORT_DIPSETTING(	0x08, DEF_STR( 2C_1C ) )
	PORT_DIPSETTING(	0x04, DEF_STR( 3C_2C ) )
	PORT_DIPSETTING(	0x01, DEF_STR( 4C_3C ) )
	PORT_DIPSETTING(	0x0f, DEF_STR( 1C_1C ) )
	PORT_DIPSETTING(	0x03, DEF_STR( 3C_4C ) )
	PORT_DIPSETTING(	0x07, DEF_STR( 2C_3C ) )
	PORT_DIPSETTING(	0x0e, DEF_STR( 1C_2C ) )
	PORT_DIPSETTING(	0x06, DEF_STR( 2C_5C ) )
	PORT_DIPSETTING(	0x0d, DEF_STR( 1C_3C ) )
	PORT_DIPSETTING(	0x0c, DEF_STR( 1C_4C ) )
	PORT_DIPSETTING(	0x0b, DEF_STR( 1C_5C ) )
	PORT_DIPSETTING(	0x0a, DEF_STR( 1C_6C ) )
	PORT_DIPSETTING(	0x09, DEF_STR( 1C_7C ) )
	PORT_DIPSETTING(	0x00, DEF_STR( Free_Play ) )
	PORT_DIPNAME( 0xf0, 0xf0, DEF_STR( Coin_B ) )		PORT_DIPLOCATION("SW1:5,6,7,8")
	PORT_DIPSETTING(	0x20, DEF_STR( 4C_1C ) )
	PORT_DIPSETTING(	0x50, DEF_STR( 3C_1C ) )
	PORT_DIPSETTING(	0x80, DEF_STR( 2C_1C ) )
	PORT_DIPSETTING(	0x40, DEF_STR( 3C_2C ) )
	PORT_DIPSETTING(	0x10, DEF_STR( 4C_3C ) )
	PORT_DIPSETTING(	0xf0, DEF_STR( 1C_1C ) )
	PORT_DIPSETTING(	0x30, DEF_STR( 3C_4C ) )
	PORT_DIPSETTING(	0x70, DEF_STR( 2C_3C ) )
	PORT_DIPSETTING(	0xe0, DEF_STR( 1C_2C ) )
	PORT_DIPSETTING(	0x60, DEF_STR( 2C_5C ) )
	PORT_DIPSETTING(	0xd0, DEF_STR( 1C_3C ) )
	PORT_DIPSETTING(	0xc0, DEF_STR( 1C_4C ) )
	PORT_DIPSETTING(	0xb0, DEF_STR( 1C_5C ) )
	PORT_DIPSETTING(	0xa0, DEF_STR( 1C_6C ) )
	PORT_DIPSETTING(	0x90, DEF_STR( 1C_7C ) )
//  PORT_DIPSETTING(    0x00, "Invalid" )

	PORT_START("DSW2")
	PORT_DIPNAME( 0x03, 0x02, DEF_STR( Lives ) )		PORT_DIPLOCATION("SW2:1,2")
	PORT_DIPSETTING(	0x03, "2" )
	PORT_DIPSETTING(	0x02, "3" )
	PORT_DIPSETTING(	0x01, "5" )
	PORT_DIPSETTING(	0x00, "7" )
	PORT_DIPNAME( 0x04, 0x00, DEF_STR( Cabinet ) )		PORT_DIPLOCATION("SW2:3")
	PORT_DIPSETTING(	0x00, DEF_STR( Upright ) )
	PORT_DIPSETTING(	0x04, DEF_STR( Cocktail ) )
	PORT_DIPNAME( 0x18, 0x18, DEF_STR( Bonus_Life ) )	PORT_DIPLOCATION("SW2:4,5")
	PORT_DIPSETTING(	0x18, "30k And Every 70k" )
	PORT_DIPSETTING(	0x10, "40k And Every 80k" )
	PORT_DIPSETTING(	0x08, "40k" )
	PORT_DIPSETTING(	0x00, "50k" )
	PORT_DIPNAME( 0x60, 0x40, DEF_STR( Difficulty ) )	PORT_DIPLOCATION("SW2:6,7")
	PORT_DIPSETTING(	0x60, DEF_STR( Easy ) )
	PORT_DIPSETTING(	0x40, DEF_STR( Normal ) )
	PORT_DIPSETTING(	0x20, "Difficult" )
	PORT_DIPSETTING(	0x00, "Very Difficult" )
	PORT_DIPNAME( 0x80, 0x00, DEF_STR( Demo_Sounds ) )	PORT_DIPLOCATION("SW2:8")
	PORT_DIPSETTING(	0x80, DEF_STR( Off ) )
	PORT_DIPSETTING(	0x00, DEF_STR( On ) )

	PORT_START("DSW3")
	PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_COIN1 )
	PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_COIN2 )
	PORT_BIT( 0x04, IP_ACTIVE_LOW, IPT_SERVICE1 )
	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_START1 )
	PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_START2 )
	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Flip_Screen ) )	PORT_DIPLOCATION("SW3:1")
	PORT_DIPSETTING(	0x20, DEF_STR( Off ) )
	PORT_DIPSETTING(	0x00, DEF_STR( On ) )
	PORT_DIPNAME( 0x40, 0x40, "Upright Controls" )		PORT_DIPLOCATION("SW3:2")
	PORT_DIPSETTING(	0x40, DEF_STR( Single ) )
	PORT_DIPSETTING(	0x00, DEF_STR( Dual ) )
	PORT_SERVICE_DIPLOC(0x80, IP_ACTIVE_LOW, "SW3:3" )

	PORT_START("P1")
	PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(1)
	PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(1)
	PORT_BIT( 0x04, IP_ACTIVE_LOW, IPT_JOYSTICK_UP	 ) PORT_8WAY PORT_PLAYER(1)
	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(1)
	PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(1)
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_UNKNOWN )
	PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_UNKNOWN )
	PORT_DIPNAME( 0x80, 0x80, DEF_STR( Allow_Continue ) ) PORT_DIPLOCATION("SW3:4")
	PORT_DIPSETTING(	0x80, "3 Times" )
	PORT_DIPSETTING(	0x00, "5 Times" )

	PORT_START("P2")
	PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT ) PORT_8WAY PORT_PLAYER(2)
	PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT ) PORT_8WAY PORT_PLAYER(2)
	PORT_BIT( 0x04, IP_ACTIVE_LOW, IPT_JOYSTICK_UP	 ) PORT_8WAY PORT_PLAYER(2)
	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN ) PORT_8WAY PORT_PLAYER(2)
	PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_BUTTON1 ) PORT_PLAYER(2)
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_UNUSED )
	PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_UNUSED )
	PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_UNUSED )
INPUT_PORTS_END

static INPUT_PORTS_START( thehustj )
	PORT_INCLUDE( battlnts )

	PORT_MODIFY("DSW2")
	PORT_DIPNAME( 0x03, 0x02, "Balls" )					PORT_DIPLOCATION("SW2:1,2")
	PORT_DIPSETTING(	0x03, "1" )
	PORT_DIPSETTING(	0x02, "2" )
	PORT_DIPSETTING(	0x01, "3" )
	PORT_DIPSETTING(	0x00, "6" )
	PORT_DIPNAME( 0x18, 0x18, "Time To Aim" )			PORT_DIPLOCATION("SW2:4,5")
	PORT_DIPSETTING(	0x18, "25s (Stage 1: 30s)" )
	PORT_DIPSETTING(	0x10, "20s (Stage 1: 25s)" )
	PORT_DIPSETTING(	0x08, "17s (Stage 1: 22s)" )
	PORT_DIPSETTING(	0x00, "15s (Stage 1: 20s)" )

	PORT_MODIFY("DSW3")
	PORT_DIPUNUSED_DIPLOC( 0x40, 0x40, "SW3:2" )

	PORT_MODIFY("P1")
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(1)
	PORT_DIPUNUSED_DIPLOC( 0x80, 0x80, "SW3:4" )

	PORT_MODIFY("P2")
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_BUTTON2 ) PORT_PLAYER(2)
INPUT_PORTS_END


static const gfx_layout charlayout =
{
	8,8,			/* 8 x 8 characters */
	0x40000/32, 	/* 8192 characters */
	4,				/* 4bpp */
	{ 0, 1, 2, 3 }, /* the four bitplanes are packed in one nibble */
	{ 2*4, 3*4, 0*4, 1*4, 6*4, 7*4, 4*4, 5*4 },
	{ 0*32, 1*32, 2*32, 3*32, 4*32, 5*32, 6*32, 7*32 },
	32*8			/* every character takes 32 consecutive bytes */
};

static const gfx_layout spritelayout =
{
	8,8,			/* 8*8 sprites */
	0x40000/32, /* 8192 sprites */
	4,				/* 4 bpp */
	{ 0, 1, 2, 3 }, /* the four bitplanes are packed in one nibble */
	{ 0*4, 1*4, 2*4, 3*4, 4*4, 5*4, 6*4, 7*4},
	{ 0*32, 1*32, 2*32, 3*32, 4*32, 5*32, 6*32, 7*32 },
	32*8			/* every sprite takes 32 consecutive bytes */
};


static GFXDECODE_START( battlnts )
	GFXDECODE_ENTRY( "gfx1", 0, charlayout,		0, 1 ) /* colors  0-15 */
	GFXDECODE_ENTRY( "gfx2", 0, spritelayout, 4*16, 1 ) /* colors 64-79 */
GFXDECODE_END

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

    Machine Driver

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

static MACHINE_DRIVER_START( battlnts )

	/* basic machine hardware */
	MDRV_CPU_ADD("maincpu", HD6309, 3000000*4)		/* ? */
	MDRV_CPU_PROGRAM_MAP(battlnts_map,0)
	MDRV_CPU_VBLANK_INT("screen", battlnts_interrupt)

	MDRV_CPU_ADD("audiocpu", Z80, 3579545)
	MDRV_CPU_PROGRAM_MAP(battlnts_sound_map,0)

	/* video hardware */
	MDRV_SCREEN_ADD("screen", RASTER)
	MDRV_SCREEN_REFRESH_RATE(60)
	MDRV_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(0))
	MDRV_SCREEN_FORMAT(BITMAP_FORMAT_INDEXED16)
	MDRV_SCREEN_SIZE(32*8, 32*8)
	MDRV_SCREEN_VISIBLE_AREA(0*8, 32*8-1, 2*8, 30*8-1)
	MDRV_GFXDECODE(battlnts)
	MDRV_PALETTE_LENGTH(128)

	MDRV_VIDEO_START(battlnts)
	MDRV_VIDEO_UPDATE(battlnts)

	/* sound hardware */
	MDRV_SPEAKER_STANDARD_MONO("mono")

	MDRV_SOUND_ADD("ym1", YM3812, 3000000)
	MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 1.0)

	MDRV_SOUND_ADD("ym2", YM3812, 3000000)
	MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 1.0)
MACHINE_DRIVER_END


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

  Game ROMs

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

ROM_START( battlnts )
	ROM_REGION( 0x20000, "maincpu", 0 ) /* code + banked roms */
	ROM_LOAD( "777_g02.7e", 0x08000, 0x08000, CRC(dbd8e17e) SHA1(586a22b714011c67a915c4a350ceca19ff875635) ) /* fixed ROM */
	ROM_LOAD( "777_g03.8e", 0x10000, 0x10000, CRC(7bd44fef) SHA1(308ec5246f5537b34e368535672ac687f456750a) ) /* banked ROM */

	ROM_REGION( 0x10000, "audiocpu", 0 ) /* 64k for the sound CPU */
	ROM_LOAD( "777_c01.10a",  0x00000, 0x08000, CRC(c21206e9) SHA1(7b133e04be67dc061a186ab0481d848b69b370d7) )

	ROM_REGION( 0x40000, "gfx1", ROMREGION_DISPOSE )
	ROM_LOAD( "777_c04.13a",  0x00000, 0x40000, CRC(45d92347) SHA1(8537b4ccd0a80ea3260ef82fde177f1d65a49c03) ) /* tiles */

	ROM_REGION( 0x40000, "gfx2", ROMREGION_DISPOSE )
	ROM_LOAD( "777_c05.13e",  0x00000, 0x40000, CRC(aeee778c) SHA1(fc58ada9c97361d13439b7b0918c947d48402445) ) /* sprites */
ROM_END

ROM_START( battlntj )
	ROM_REGION( 0x20000, "maincpu", 0 ) /* code + banked roms */
	ROM_LOAD( "777_e02.7e",  0x08000, 0x08000, CRC(d631cfcb) SHA1(7787da0dd8cd218abc27204e517e04d7a1913a3b) ) /* fixed ROM */
	ROM_LOAD( "777_e03.8e",  0x10000, 0x10000, CRC(5ef1f4ef) SHA1(e3e6e1fc5a65328d94c23e2e76eef3504b70e58b) ) /* banked ROM */

	ROM_REGION( 0x10000, "audiocpu", 0 ) /* 64k for the sound CPU */
	ROM_LOAD( "777_c01.10a",  0x00000, 0x08000, CRC(c21206e9) SHA1(7b133e04be67dc061a186ab0481d848b69b370d7) )

	ROM_REGION( 0x40000, "gfx1", ROMREGION_DISPOSE )
	ROM_LOAD( "777_c04.13a",  0x00000, 0x40000, CRC(45d92347) SHA1(8537b4ccd0a80ea3260ef82fde177f1d65a49c03) ) /* tiles */

	ROM_REGION( 0x40000, "gfx2", ROMREGION_DISPOSE )
	ROM_LOAD( "777_c05.13e",  0x00000, 0x40000, CRC(aeee778c) SHA1(fc58ada9c97361d13439b7b0918c947d48402445) ) /* sprites */
ROM_END

ROM_START( rackemup )
	ROM_REGION( 0x20000, "maincpu", 0 ) /* code + banked roms */
	ROM_LOAD( "765_l02.7e",  0x08000, 0x08000, CRC(3dfc48bd) SHA1(9ba98e9f27dd0a6efec145bea2a5ae7df8567437) ) /* fixed ROM */
	ROM_LOAD( "765_j03.8e",  0x10000, 0x10000, CRC(a13fd751) SHA1(27ec66835c85b7ac0221a813d38e9cca0d9be3b8) ) /* banked ROM */

	ROM_REGION( 0x10000, "audiocpu", 0 ) /* 64k for the sound CPU */
	ROM_LOAD( "765_j01.10a", 0x00000, 0x08000, CRC(77ae753e) SHA1(9e463a825d31bb79644b083d24b25670d96441c5) )

	ROM_REGION( 0x40000, "gfx1", ROMREGION_DISPOSE )
	ROM_LOAD( "765_l04.13a", 0x00000, 0x40000, CRC(acfbeee2) SHA1(c2bf750892ba33d4610fa4497170f49c101ed4c1) ) /* tiles */

	ROM_REGION( 0x40000, "gfx2", ROMREGION_DISPOSE )
	ROM_LOAD( "765_l05.13e", 0x00000, 0x40000, CRC(1bb6855f) SHA1(251081564dfede8fa9a422081d58465fe5ca4ed1) ) /* sprites */
ROM_END

ROM_START( thehustl )
	ROM_REGION( 0x20000, "maincpu", 0 ) /* code + banked roms */
	ROM_LOAD( "765_m02.7e",  0x08000, 0x08000, CRC(934807b9) SHA1(84e13a5c1587ee28330f369f9a1180219edbda9d) ) /* fixed ROM */
	ROM_LOAD( "765_j03.8e",  0x10000, 0x10000, CRC(a13fd751) SHA1(27ec66835c85b7ac0221a813d38e9cca0d9be3b8) ) /* banked ROM */

	ROM_REGION( 0x10000, "audiocpu", 0 ) /* 64k for the sound CPU */
	ROM_LOAD( "765_j01.10a", 0x00000, 0x08000, CRC(77ae753e) SHA1(9e463a825d31bb79644b083d24b25670d96441c5) )

	ROM_REGION( 0x40000, "gfx1", ROMREGION_DISPOSE )
	ROM_LOAD( "765_e04.13a", 0x00000, 0x40000, CRC(08c2b72e) SHA1(02d9c690da839d6fee75fffdf66a4d3da35a0263) ) /* tiles */

	ROM_REGION( 0x40000, "gfx2", ROMREGION_DISPOSE )
	ROM_LOAD( "765_e05.13e", 0x00000, 0x40000, CRC(ef044655) SHA1(c8272283eab8fc2899979da398819cb72c92a299) ) /* sprites */
ROM_END

ROM_START( thehustj )
	ROM_REGION( 0x20000, "maincpu", 0 ) /* code + banked roms */
	ROM_LOAD( "765_j02.7e",  0x08000, 0x08000, CRC(2ac14c75) SHA1(b88f6279ab88719f4207e28486a0022554668382) ) /* fixed ROM */
	ROM_LOAD( "765_j03.8e",  0x10000, 0x10000, CRC(a13fd751) SHA1(27ec66835c85b7ac0221a813d38e9cca0d9be3b8) ) /* banked ROM */

	ROM_REGION( 0x10000, "audiocpu", 0 ) /* 64k for the sound CPU */
	ROM_LOAD( "765_j01.10a", 0x00000, 0x08000, CRC(77ae753e) SHA1(9e463a825d31bb79644b083d24b25670d96441c5) )

	ROM_REGION( 0x40000, "gfx1", ROMREGION_DISPOSE )
	ROM_LOAD( "765_e04.13a", 0x00000, 0x40000, CRC(08c2b72e) SHA1(02d9c690da839d6fee75fffdf66a4d3da35a0263) ) /* tiles */

	ROM_REGION( 0x40000, "gfx2", ROMREGION_DISPOSE )
	ROM_LOAD( "765_e05.13e", 0x00000, 0x40000, CRC(ef044655) SHA1(c8272283eab8fc2899979da398819cb72c92a299) ) /* sprites */
ROM_END


/*
    This recursive function doesn't use additional memory
    (it could be easily converted into an iterative one).
    It's called shuffle because it mimics the shuffling of a deck of cards.
*/
static void shuffle(UINT8 *buf,int len)
{
	int i;
	UINT8 t;

	if (len == 2) return;

	if (len % 4) fatalerror("shuffle() - not modulo 4");	/* must not happen */

	len /= 2;

	for (i = 0;i < len/2;i++)
	{
		t = buf[len/2 + i];
		buf[len/2 + i] = buf[len + i];
		buf[len + i] = t;
	}

	shuffle(buf,len);
	shuffle(buf + len,len);
}


static DRIVER_INIT( rackemup )
{
	/* rearrange char ROM */
	shuffle(memory_region(machine, "gfx1"),memory_region_length(machine, "gfx1"));
}



GAME( 1987, battlnts, 0,        battlnts, battlnts, 0,        ROT90, "Konami", "Battlantis", 0 )
GAME( 1987, battlntj, battlnts, battlnts, battlnts, 0,        ROT90, "Konami", "Battlantis (Japan)", 0 )
GAME( 1987, rackemup, 0,        battlnts, thehustj, rackemup, ROT90, "Konami", "Rack 'em Up", GAME_NO_COCKTAIL )
GAME( 1987, thehustl, rackemup, battlnts, thehustj, 0,        ROT90, "Konami", "The Hustler (Japan version M)", GAME_NO_COCKTAIL )
GAME( 1987, thehustj, rackemup, battlnts, thehustj, 0,        ROT90, "Konami", "The Hustler (Japan version J)", GAME_NO_COCKTAIL )

