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r8630 Sunday 25th July, 2010 at 21:40:25 UTC by Angelo Salese
[BASIC MASTER LV3]: added mc6845 hook up

[src/mess/drivers]

bml3.c

src/mess/drivers/bml3.c

r8629	r8630
1	1	/***************************************************************************
2
	2
3	3	Hitachi Basic Master Level 3 (MB-6890)
4	4
5	5	13/07/2010 Skeleton driver.
r8629	r8630
8	8
9	9	#include "emu.h"
10	10	#include "cpu/m6809/m6809.h"
	11	#include "video/mc6845.h"
11	12
	13	static VIDEO_START( bml3 )
	14	{
	15	}
	16
	17	static VIDEO_UPDATE( bml3 )
	18	{
	19	return 0;
	20	}
	21
	22	static WRITE8_HANDLER( bml3_6845_w )
	23	{
	24	static int addr_latch;
	25
	26	if(offset == 0)
	27	{
	28	addr_latch = data;
	29	mc6845_address_w(space->machine->device("crtc"), 0,data);
	30	}
	31	else
	32	{
	33	/*if(addr_latch == 0x0a)
	34	cursor_raster = data;
	35	if(addr_latch == 0x0e)
	36	cursor_addr = ((data<<8) & 0x3f00) | (cursor_addr & 0xff);
	37	else if(addr_latch == 0x0f)
	38	cursor_addr = (cursor_addr & 0x3f00) | (data & 0xff);*/
	39
	40	mc6845_register_w(space->machine->device("crtc"), 0,data);
	41	}
	42	}
	43
	44	/* Note: this custom code is there just for simplicity, it'll be nuked in the end */
	45	static READ8_HANDLER( bml3_io_r )
	46	{
	47	static UINT8 *rom = memory_region(space->machine, "maincpu");
	48
	49	if(offset < 0xc0)
	50	{
	51	logerror("I/O read [%02x] at PC=%04x\n",offset,cpu_get_pc(space->cpu));
	52	return 0;
	53	}
	54
	55	if(offset == 0xc8) //this seems the keyboard status
	56	return 0;
	57
	58	/* TODO: pretty sure that there's a bankswitch for this */
	59	return rom[offset+0xff00];
	60	}
	61
	62	static WRITE8_HANDLER( bml3_io_w )
	63	{
	64	if(offset == 0xc6 || offset == 0xc7) { bml3_6845_w(space,offset-0xc6,data); }
	65	else
	66	{
	67	logerror("I/O write %02x -> [%02x] at PC=%04x\n",data,offset,cpu_get_pc(space->cpu));
	68	}
	69	}
	70
12	71	static ADDRESS_MAP_START(bml3_mem, ADDRESS_SPACE_PROGRAM, 8)
13	72	ADDRESS_MAP_UNMAP_HIGH
14		AM_RANGE(0x0000, 0x9FFF) AM_RAM
15		AM_RANGE(0xA000, 0xFFFF) AM_ROM
	73	AM_RANGE(0x0000, 0x9fff) AM_RAM
	74	AM_RANGE(0xff00, 0xffff) AM_READWRITE(bml3_io_r,bml3_io_w)
	75	AM_RANGE(0xa000, 0xffff) AM_ROM
16	76	ADDRESS_MAP_END
17	77
18	78
r8629	r8630
21	81	INPUT_PORTS_END
22	82
23	83
24		static MACHINE_RESET(bml3)
25		{
26		}
27
28		static VIDEO_START( bml3 )
	84	static MACHINE_RESET(bml3)
29	85	{
30	86	}
31	87
32		static VIDEO_UPDATE( bml3 )
	88	static const mc6845_interface mc6845_intf =
33	89	{
34		return 0;
35		}
	90	"screen",   /* screen we are acting on */
	91	8,         /* number of pixels per video memory address */
	92	NULL,      /* before pixel update callback */
	93	NULL,      /* row update callback */
	94	NULL,      /* after pixel update callback */
	95	DEVCB_NULL,   /* callback for display state changes */
	96	DEVCB_NULL,   /* callback for cursor state changes */
	97	DEVCB_NULL,   /* HSYNC callback */
	98	DEVCB_NULL,   /* VSYNC callback */
	99	NULL      /* update address callback */
	100	};
36	101
	102
37	103	static MACHINE_DRIVER_START( bml3 )
38	104	/* basic machine hardware */
39	105	MDRV_CPU_ADD("maincpu",M6809, XTAL_1MHz)
40	106	MDRV_CPU_PROGRAM_MAP(bml3_mem)
41	107
42	108	MDRV_MACHINE_RESET(bml3)
43
	109
44	110	/* video hardware */
45	111	MDRV_SCREEN_ADD("screen", RASTER)
46		MDRV_SCREEN_REFRESH_RATE(50)
	112	MDRV_SCREEN_REFRESH_RATE(60)
47	113	MDRV_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(2500)) /* not accurate */
48	114	MDRV_SCREEN_FORMAT(BITMAP_FORMAT_INDEXED16)
49	115	MDRV_SCREEN_SIZE(640, 480)
r8629	r8630
51	117	MDRV_PALETTE_LENGTH(2)
52	118	MDRV_PALETTE_INIT(black_and_white)
53	119
	120	MDRV_MC6845_ADD("crtc", H46505, XTAL_3_579545MHz, mc6845_intf)   /* unknown clock, hand tuned to get ~60 fps */
	121
	122
54	123	MDRV_VIDEO_START(bml3)
55	124	MDRV_VIDEO_UPDATE(bml3)
56	125	MACHINE_DRIVER_END

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