exerion.c

这个是延伸mame的在wince平台下的游戏模拟器的代码

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

Exerion by Jaleco

Exerion is a unique driver in that it has idiosyncracies that are straight
out of Bizarro World. I submit for your approval:

* The mystery reads from $d802 - timer-based protection?
* The freakish graphics encoding scheme, which no other MAME-supported game uses
* The sprite-ram, and all the funky parameters that go along with it
* The unusual parallaxed background. Is it controlled by the 2nd CPU?

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

#include "driver.h"
#include "vidhrdw/generic.h"

void exerion_vh_convert_color_prom(unsigned char *palette, unsigned short *colortable,const unsigned char *color_prom);
int exerion_vh_start (void);
void exerion_vh_stop (void);
void exerion_vh_screenrefresh(struct osd_bitmap *bitmap,int full_refresh);

extern void exerion_videoreg_w (int offset,int data);

/* This is the first of many Exerion "features." No clue if it's */
/* protection or some sort of timer. */
int exerion_porta_r (int offset)
{
	static unsigned char val = 0xbe;

	val ^= 0x40;
	return val;
}



static struct MemoryReadAddress readmem[] =
{
	{ 0x0000, 0x5fff, MRA_ROM },
	{ 0x6000, 0x67ff, MRA_RAM },
	{ 0x8000, 0x8bff, MRA_RAM },
	{ 0xa000, 0xa000, input_port_0_r },
	{ 0xa800, 0xa800, input_port_1_r },
	{ 0xb000, 0xb000, input_port_2_r },
	{ 0xd802, 0xd802, AY8910_read_port_1_r },
	{ -1 }  /* end of table */
};

static struct MemoryWriteAddress writemem[] =
{
	{ 0x0000, 0x5fff, MWA_ROM },
	{ 0x6000, 0x67ff, MWA_RAM },
	{ 0x8000, 0x87ff, videoram_w, &videoram, &videoram_size },
	{ 0x8800, 0x887f, MWA_RAM, &spriteram, &spriteram_size },
	{ 0x8800, 0x8bff, MWA_RAM },
	{ 0xc000, 0xc000, exerion_videoreg_w },
	{ 0xc800, 0xc800, soundlatch_w },
	{ 0xd000, 0xd000, AY8910_control_port_0_w },
	{ 0xd001, 0xd001, AY8910_write_port_0_w },
	{ 0xd800, 0xd800, AY8910_control_port_1_w },
	{ 0xd801, 0xd801, AY8910_write_port_1_w },
	{ -1 }  /* end of table */
};

#ifdef TRY_CPU2
static struct MemoryReadAddress cpu2_readmem[] =
{
	{ 0x0000, 0x1fff, MRA_ROM },
	{ 0x4000, 0x47ff, MRA_RAM },
	{ 0x6000, 0x6000, soundlatch_r },
	{ -1 }  /* end of table */
};

static struct MemoryWriteAddress cpu2_writemem[] =
{
	{ 0x0000, 0x1fff, MWA_ROM },
	{ 0x4000, 0x47ff, MWA_RAM },
	{ -1 }  /* end of table */
};
#endif


/* Exerion triggers NMIs on vblank */
int exerion_interrupt(void)
{
	if (readinputport(3) & 1)
		return nmi_interrupt();
	else return ignore_interrupt();
}

INPUT_PORTS_START( exerion_input_ports )
	PORT_START      /* IN0 */
	PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_JOYSTICK_UP | IPF_8WAY )
	PORT_BIT( 0x02, IP_ACTIVE_LOW, IPT_JOYSTICK_DOWN | IPF_8WAY )
	PORT_BIT( 0x04, IP_ACTIVE_LOW, IPT_JOYSTICK_RIGHT | IPF_8WAY )
	PORT_BIT( 0x08, IP_ACTIVE_LOW, IPT_JOYSTICK_LEFT | IPF_8WAY )
	PORT_BIT( 0x10, IP_ACTIVE_LOW, IPT_BUTTON2 )
	PORT_BIT( 0x20, IP_ACTIVE_LOW, IPT_BUTTON1 )
	PORT_BIT( 0x40, IP_ACTIVE_LOW, IPT_START1 )
	PORT_BIT( 0x80, IP_ACTIVE_LOW, IPT_START2 )

	PORT_START      /* DSW0 */
	PORT_DIPNAME( 0x07, 0x02, "Lives", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "1" )
	PORT_DIPSETTING(    0x01, "2" )
	PORT_DIPSETTING(    0x02, "3" )
	PORT_DIPSETTING(    0x03, "4" )
	PORT_DIPSETTING(    0x04, "5" )
	PORT_DIPSETTING(    0x07, "Infinite" )
	PORT_DIPNAME( 0x18, 0x00, "Bonus Life", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "10000" )
	PORT_DIPSETTING(    0x08, "20000" )
	PORT_DIPSETTING(    0x10, "30000" )
	PORT_DIPSETTING(    0x18, "40000" )
	PORT_DIPNAME( 0x20, 0x20, "Coinage", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "2 Coins/1 Credit" )
	PORT_DIPSETTING(    0x20, "1 Coin/1 Credit" )
	PORT_DIPNAME( 0x40, 0x00, "Difficulty", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "Easy" )
	PORT_DIPSETTING(    0x40, "Hard" )
	PORT_DIPNAME( 0x80, 0x00, "Unknown", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "Off" )
	PORT_DIPSETTING(    0x80, "On" )

	PORT_START      /* VBLANK */
	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_VBLANK )
	PORT_DIPNAME( 0x02, 0x00, "Unknown", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "Off" )
	PORT_DIPSETTING(    0x02, "On" )
	PORT_DIPNAME( 0x04, 0x00, "Unknown", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "Off" )
	PORT_DIPSETTING(    0x04, "On" )
	PORT_DIPNAME( 0x08, 0x00, "Unknown", IP_KEY_NONE )
	PORT_DIPSETTING(    0x00, "Off" )
	PORT_DIPSETTING(    0x08, "On" )
	PORT_BIT( 0xf0, IP_ACTIVE_LOW, IPT_UNUSED )

	PORT_START      /* FAKE */
	/* The coin slots are not memory mapped. */
	/* This fake input port is used by the interrupt */
	/* handler to be notified of coin insertions. We use IPF_IMPULSE to */
	/* trigger exactly one interrupt, without having to check when the */
	/* user releases the key. */
	PORT_BITX(0x01, IP_ACTIVE_HIGH, IPT_COIN1 | IPF_IMPULSE,
			IP_NAME_DEFAULT, IP_KEY_DEFAULT, IP_JOY_DEFAULT, 1 )
INPUT_PORTS_END



static struct GfxLayout charlayout =
{
	8,8,            /* 8*8 characters */
	512,          /* total number of chars */
	2,              /* 2 bits per pixel (# of planes) */
	{ 0, 4 },       /* start of every bitplane */
	{ 3, 2, 1, 0, 8+3, 8+2, 8+1, 8+0 },
	{ 16*0, 16*1, 16*2, 16*3, 16*4, 16*5, 16*6, 16*7 },
	16*8            /* every char takes 16 consecutive bytes */
};

static struct GfxLayout bgcharlayout =
{
	32,32,            /* 64*8 characters */
	128,          /* total number of chars */
	2,              /* 2 bits per pixel (# of planes) */
	{ 0, 4 },       /* start of every bitplane */
	{ 3, 2, 1, 0, 8+3, 8+2, 8+1, 8+0,
			2*8+3, 2*8+2, 2*8+1, 2*8+0, 3*8+3, 3*8+2, 3*8+1, 3*8+0,
			4*8+3, 4*8+2, 4*8+1, 4*8+0, 5*8+3, 5*8+2, 5*8+1, 5*8+0,
			6*8+3, 6*8+2, 6*8+1, 6*8+0, 7*8+3, 7*8+2, 7*8+1, 7*8+0 },
	{ 64*0, 64*1, 64*2, 64*3, 64*4, 64*5, 64*6, 64*7,
			64*8, 64*9, 64*10, 64*11, 64*12, 64*13, 64*14, 64*15,
			64*16, 64*17, 64*18, 64*19, 64*20, 64*21, 64*22, 64*23,
			64*24, 64*25, 64*26, 64*27, 64*28, 64*29, 64*30, 64*31 },
	64*32            /* every char takes 16 consecutive bytes */
};

/* 16 x 16 sprites -- requires reorganizing characters in exerion_decode() */
static struct GfxLayout spritelayout =
{
	16,16,          /* 16*16 sprites */
	128*2,          /* total number of sprites in the rom */
	2,              /* 2 bits per pixel (# of planes) */
	{ 0, 4 },       /* start of every bitplane */
	{  3, 2, 1, 0, 8+3, 8+2, 8+1, 8+0,
			128+3, 128+2, 128+1, 128+0, 128+8+3, 128+8+2, 128+8+1, 128+8+0 },
	{ 16*0, 16*1, 16*2, 16*3, 16*4, 16*5, 16*6, 16*7,
			256+16*0, 256+16*1, 256+16*2, 256+16*3, 256+16*4, 256+16*5, 256+16*6, 256+16*7 },
	64*8            /* every sprite takes 64 consecutive bytes */
};

/* Quick and dirty way to emulate pixel-doubled sprites. */
static struct GfxLayout bigspritelayout =
{
	32,32,          /* 32*32 sprites */
	128*2,          /* total number of sprites in the rom */
	2,              /* 2 bits per pixel (# of planes) */
	{ 0, 4 },       /* start of every bitplane */
	{ 3, 3, 2, 2, 1, 1, 0, 0, 8+3, 8+3, 8+2, 8+2, 8+1, 8+1, 8+0, 8+0,
			128+3, 128+3, 128+2, 128+2, 128+1, 128+1, 128+0, 128+0,
			128+8+3, 128+8+3, 128+8+2, 128+8+2, 128+8+1, 128+8+1, 128+8+0, 128+8+0 },
	{ 16*0, 16*0, 16*1, 16*1, 16*2, 16*2, 16*3, 16*3,
			16*4, 16*4, 16*5, 16*5, 16*6, 16*6, 16*7, 16*7,
			256+16*0, 256+16*0, 256+16*1, 256+16*1, 256+16*2, 256+16*2, 256+16*3, 256+16*3,
			256+16*4, 256+16*4, 256+16*5, 256+16*5, 256+16*6, 256+16*6, 256+16*7, 256+16*7 },
	64*8            /* every sprite takes 64 consecutive bytes */
};

static struct GfxDecodeInfo gfxdecodeinfo[] =
{
	{ 1, 0x0000, &charlayout,           0, 64 },
	{ 1, 0x2000, &bgcharlayout,      64*4, 64 },
	{ 1, 0xa000, &spritelayout,    2*64*4, 64 },
	{ 1, 0xa000, &bigspritelayout, 2*64*4, 64 },
	{ -1 } /* end of array */
};



static struct AY8910interface ay8910_interface =
{
	2,	/* 2 chips */
	10000000/6,	/* 1.666 MHz */
	{ 0x20ff, 0x20ff },
	{ 0, exerion_porta_r },
	{ 0 },
	{ 0 },
	{ 0 }
};



static struct MachineDriver machine_driver =
{
	/* basic machine hardware */
	{
		{
			CPU_Z80,
			10000000/3,	/* 3.333 MHz */
			0,
			readmem,writemem,0,0,
			exerion_interrupt,1
		},
#ifdef TRY_CPU2
		{
			CPU_Z80,
			10000000/3,	/* 3.333 MHz */
			3,      /* memory region #3 */
			cpu2_readmem,cpu2_writemem,0,0,
			ignore_interrupt,0
		}
#endif
	},
	60, DEFAULT_REAL_60HZ_VBLANK_DURATION,	/* frames per second, vblank duration */
	1,	/* 1 CPU slice per frame - interleaving is forced when a sound command is written */
	0,

	/* video hardware */
	64*8, 32*8, { 12*8, 52*8-1, 2*8, 30*8-1 },
	gfxdecodeinfo,
	32,64*4+64*4+64*4,
	exerion_vh_convert_color_prom,

	VIDEO_TYPE_RASTER|VIDEO_SUPPORTS_DIRTY,
	0,
	exerion_vh_start,
	exerion_vh_stop,
	exerion_vh_screenrefresh,

	/* sound hardware */
	0,0,0,0,
	{
		{
			SOUND_AY8910,
			&ay8910_interface
		}
	}
};



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

  Game driver(s)

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

ROM_START( exerion_rom )
	ROM_REGION(0x10000)     /* 64k for code */
	ROM_LOAD( "exerion.07",   0x0000, 0x2000, 0x4c78d57d )
	ROM_LOAD( "exerion.08",   0x2000, 0x2000, 0xdcadc1df )
	ROM_LOAD( "exerion.09",   0x4000, 0x2000, 0x34cc4d14 )

	ROM_REGION_DISPOSE(0x1c000)     /* temporary space for graphics (disposed after conversion) */
	/* Set aside 0xe000 for the unscrambled graphics */