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author Curt Coder <curtcoder@mail.com>2008-11-04 11:52:42 +0000
committer Curt Coder <curtcoder@mail.com>2008-11-04 11:52:42 +0000
commit7d4023e2c48e5a84d41110698d0f60d287ca190f (patch)
tree1cc7a425863cf7fdc42f053a422d443c6b3a056b /src
parent6fb55dfbf7c8d8f00b0c67c1631e34dc31f54c64 (diff)
[MC6845] Reverted all changes.
Diffstat (limited to 'src')
-rw-r--r--src/emu/video/mc6845.c60
1 files changed, 10 insertions, 50 deletions
diff --git a/src/emu/video/mc6845.c b/src/emu/video/mc6845.c
index a91090d4253..a7fd139895a 100644
--- a/src/emu/video/mc6845.c
+++ b/src/emu/video/mc6845.c
@@ -44,18 +44,6 @@ enum
};
-/* mode control bits */
-
-#define MODE_INTERLACED 0x01 /* not supported */
-#define MODE_VIDEO 0x02 /* not supported */
-#define MODE_ROW_COLUMN_ADDRESSING 0x04 /* not supported */
-#define MODE_TRANSPARENT_ADDRESSING 0x08 /* not supported */
-#define MODE_DISPLAY_ENABLE_SKEW 0x10
-#define MODE_CURSOR_SKEW 0x20
-#define MODE_RA4_IS_UPDATE_STROBE 0x40 /* not supported */
-#define MODE_INTERLEAVED_UPDATES 0x80 /* not supported */
-
-
/* tags for state saving */
static const char * const device_tags[NUM_TYPES] = { "mc6845", "mc6845-1", "c6545-1", "r6545-1", "h46505", "hd6845", "sy6545-1" };
@@ -64,7 +52,6 @@ static const int supports_disp_start_addr_r[NUM_TYPES] = { TRUE, TRUE,
static const int supports_vert_sync_width[NUM_TYPES] = { FALSE, TRUE, TRUE, TRUE, FALSE, TRUE, TRUE };
static const int supports_status_reg_d5[NUM_TYPES] = { FALSE, FALSE, TRUE, TRUE, FALSE, FALSE, TRUE };
static const int supports_status_reg_d6[NUM_TYPES] = { FALSE, FALSE, TRUE, TRUE, FALSE, FALSE, TRUE };
-static const int supports_status_reg_d7[NUM_TYPES] = { FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE };
typedef struct _mc6845_t mc6845_t;
@@ -90,7 +77,6 @@ struct _mc6845_t
UINT16 disp_start_addr; /* 0x0c/0x0d */
UINT16 cursor_addr; /* 0x0e/0x0f */
UINT16 light_pen_addr; /* 0x10/0x11 */
- UINT16 update_addr; /* 0x12/0x13 */
/* other internal state */
UINT64 clock;
@@ -118,7 +104,6 @@ struct _mc6845_t
UINT16 vsync_off_pos;
UINT16 current_disp_addr; /* the display address currently drawn */
UINT8 light_pen_latched;
- int update_ready;
int has_valid_parameters;
};
@@ -174,10 +159,6 @@ READ8_DEVICE_HANDLER( mc6845_status_r )
if (supports_status_reg_d6[mc6845->device_type] && mc6845->light_pen_latched)
ret = ret | 0x40;
- /* update ready */
- if (supports_status_reg_d7[mc6845->device_type] && mc6845->update_ready)
- ret = ret | 0x80;
-
return ret;
}
@@ -195,7 +176,6 @@ READ8_DEVICE_HANDLER( mc6845_register_r )
case 0x0f: ret = (mc6845->cursor_addr >> 0) & 0xff; break;
case 0x10: ret = (mc6845->light_pen_addr >> 8) & 0xff; mc6845->light_pen_latched = FALSE; break;
case 0x11: ret = (mc6845->light_pen_addr >> 0) & 0xff; mc6845->light_pen_latched = FALSE; break;
- case 0x1f: mc6845->update_ready = 0; mc6845->update_addr = (mc6845->update_addr + 1) & 0x3fff; break;
/* all other registers are write only and return 0 */
default: break;
@@ -231,14 +211,11 @@ WRITE8_DEVICE_HANDLER( mc6845_register_w )
case 0x0f: mc6845->cursor_addr = ((data & 0xff) << 0) | (mc6845->cursor_addr & 0xff00); break;
case 0x10: /* read-only */ break;
case 0x11: /* read-only */ break;
- case 0x12: mc6845->update_addr = ((data & 0x3f) << 8) | (mc6845->update_addr & 0x00ff); break;
- case 0x13: mc6845->update_addr = ((data & 0xff) << 0) | (mc6845->update_addr & 0xff00); break;
- case 0x1f: mc6845->update_ready = 0; mc6845->update_addr = (mc6845->update_addr + 1) & 0x3fff; break;
default: break;
}
- /* display message if the Mode Control register has unsupported bits active */
- if ((mc6845->register_address_latch == 0x08) && (mc6845->mode_control & ~(MODE_DISPLAY_ENABLE_SKEW | MODE_CURSOR_SKEW)))
+ /* display message if the Mode Control register is not zero */
+ if ((mc6845->register_address_latch == 0x08) && (mc6845->mode_control != 0))
popmessage("Mode Control %02X is not supported!!!", mc6845->mode_control);
recompute_parameters(mc6845, FALSE);
@@ -301,8 +278,8 @@ static void recompute_parameters(mc6845_t *mc6845, int postload)
visarea.min_x = 0;
visarea.min_y = 0;
- visarea.max_x = hsync_on_pos - 1;
- visarea.max_y = vsync_on_pos - 1;
+ visarea.max_x = max_visible_x;
+ visarea.max_y = max_visible_y;
if (LOG) logerror("M6845 config screen: HTOTAL: 0x%x VTOTAL: 0x%x MAX_X: 0x%x MAX_Y: 0x%x HSYNC: 0x%x-0x%x VSYNC: 0x%x-0x%x Freq: %ffps\n",
horiz_pix_total, vert_pix_total, max_visible_x, max_visible_y, hsync_on_pos, hsync_off_pos - 1, vsync_on_pos, vsync_off_pos - 1, 1 / ATTOSECONDS_TO_DOUBLE(refresh));
@@ -333,18 +310,7 @@ static void recompute_parameters(mc6845_t *mc6845, int postload)
INLINE int is_display_enabled(mc6845_t *mc6845)
{
- int x = video_screen_get_hpos(mc6845->screen);
- int x0 = 0;
- int x1 = mc6845->max_visible_x;
- int y = video_screen_get_vpos(mc6845->screen);
-
- if (mc6845->mode_control & MODE_DISPLAY_ENABLE_SKEW)
- {
- x0 += mc6845->hpixels_per_column;
- x1 += mc6845->hpixels_per_column;
- }
-
- return (x >= x0) && (x <= x1) && (y <= mc6845->max_visible_y);
+ return !video_screen_get_vblank(mc6845->screen) && !video_screen_get_hblank(mc6845->screen);
}
@@ -388,10 +354,6 @@ static void update_de_changed_timer(mc6845_t *mc6845)
next_y = 0;
}
- /* delay display enable for 1 character time if skew is enabled */
- if (mc6845->mode_control & MODE_DISPLAY_ENABLE_SKEW)
- next_x += mc6845->hpixels_per_column;
-
if (next_y != -1)
duration = video_screen_get_time_until_pos(mc6845->screen, next_y, next_x);
else
@@ -416,6 +378,10 @@ static void update_hsync_changed_timers(mc6845_t *mc6845)
else
next_y = (video_screen_get_vpos(mc6845->screen) + 1) % mc6845->vert_pix_total;
+ /* if the next line is not in the visible region, go to the beginning of the screen */
+ if (next_y > mc6845->max_visible_y)
+ next_y = 0;
+
timer_adjust_oneshot(mc6845->hsync_on_timer, video_screen_get_time_until_pos(mc6845->screen, next_y, mc6845->hsync_on_pos) , 0);
timer_adjust_oneshot(mc6845->hsync_off_timer, video_screen_get_time_until_pos(mc6845->screen, next_y, mc6845->hsync_off_pos), 0);
}
@@ -674,7 +640,7 @@ void mc6845_update(const device_config *device, bitmap_t *bitmap, const rectangl
}
/* for each row in the visible region */
- for (y = cliprect->min_y; y <= MIN(cliprect->max_y, mc6845->max_visible_y); y++)
+ for (y = cliprect->min_y; y <= cliprect->max_y; y++)
{
/* compute the current raster line */
UINT8 ra = y % (mc6845->max_ras_addr + 1);
@@ -689,10 +655,6 @@ void mc6845_update(const device_config *device, bitmap_t *bitmap, const rectangl
/* compute the cursor X position, or -1 if not visible */
INT8 cursor_x = cursor_visible ? (mc6845->cursor_addr - mc6845->current_disp_addr) : -1;
- /* delay cursor for 1 character time if skew is enabled */
- if (mc6845->mode_control & MODE_CURSOR_SKEW)
- cursor_x += mc6845->hpixels_per_column;
-
/* call the external system to draw it */
mc6845->intf->update_row(device, bitmap, cliprect, mc6845->current_disp_addr, ra, y, mc6845->horiz_disp, cursor_x, param);
@@ -784,8 +746,6 @@ static device_start_err common_start(const device_config *device, int device_typ
state_save_register_item(unique_tag, 0, mc6845->light_pen_latched);
state_save_register_item(unique_tag, 0, mc6845->cursor_state);
state_save_register_item(unique_tag, 0, mc6845->cursor_blink_count);
- state_save_register_item(unique_tag, 0, mc6845->update_addr);
- state_save_register_item(unique_tag, 0, mc6845->update_ready);
return DEVICE_START_OK;
}