UINT16 crtc6845_get_ma(int which)
{
crtc6845_state *chip = &crtc6845;
UINT16 ret;
if (chip->has_valid_parameters)
{
/* get the current raster positions and clamp them to the visible region */
int y = video_screen_get_vpos(0);
int x = video_screen_get_hpos(0);
/* since the MA counter stops in the blanking regions, if we are in a
VBLANK, both X and Y are at their max */
if ((y > chip->last_max_y) || (x > chip->last_max_x))
x = chip->last_max_x;
if (y > chip->last_max_y)
y = chip->last_max_y;
ret = (chip->start_addr +
(y / (chip->max_ras_addr + 1)) * chip->horiz_disp +
(x / chip->intf->hpixels_per_column)) & 0x3fff;
}
else
ret = 0;
return ret;
}
static int is_display_enabled(crtc6845_state *chip)
{
UINT16 y = video_screen_get_vpos(chip->intf->scrnum);
UINT16 x = video_screen_get_hpos(chip->intf->scrnum);
return (y <= chip->last_max_y) && (x <= chip->last_max_x);
}
int video_screen_get_hblank(int scrnum)
{
int hpos = video_screen_get_hpos(scrnum);
return (hpos < Machine->screen[scrnum].visarea.min_x || hpos > Machine->screen[scrnum].visarea.max_x);
}
static TIMER_CALLBACK( vblank_interrupt_callback )
{
const device_config *upd4990a = devtag_get_device(machine, "upd4990a");
if (LOG_VIDEO_SYSTEM) logerror("+++ VBLANK @ %d,%d\n", video_screen_get_vpos(machine->primary_screen), video_screen_get_hpos(machine->primary_screen));
/* add a timer tick to the pd4990a */
upd4990a_addretrace(upd4990a);
vblank_interrupt_pending = 1;
update_interrupts(machine);
/* set timer for next screen */
timer_adjust_oneshot(vblank_interrupt_timer, video_screen_get_time_until_pos(machine->primary_screen, NEOGEO_VBSTART, 0), 0);
}
static TIMER_CALLBACK( display_position_interrupt_callback )
{
if (LOG_VIDEO_SYSTEM) logerror("--- Scanline @ %d,%d\n", video_screen_get_vpos(machine->primary_screen), video_screen_get_hpos(machine->primary_screen));
if (display_position_interrupt_control & IRQ2CTRL_ENABLE)
{
if (LOG_VIDEO_SYSTEM) logerror("*** Scanline interrupt (IRQ2) *** y: %02x x: %02x\n", video_screen_get_vpos(machine->primary_screen), video_screen_get_hpos(machine->primary_screen));
display_position_interrupt_pending = 1;
update_interrupts(machine);
}
if (display_position_interrupt_control & IRQ2CTRL_AUTOLOAD_REPEAT)
{
if (LOG_VIDEO_SYSTEM) logerror("AUTOLOAD_REPEAT ");
adjust_display_position_interrupt_timer(machine);
}
}
static void adjust_display_position_interrupt_timer(running_machine *machine)
{
if ((display_counter + 1) != 0)
{
attotime period = attotime_mul(ATTOTIME_IN_HZ(NEOGEO_PIXEL_CLOCK), display_counter + 1);
if (LOG_VIDEO_SYSTEM) logerror("adjust_display_position_interrupt_timer current y: %02x current x: %02x target y: %x target x: %x\n", video_screen_get_vpos(machine->primary_screen), video_screen_get_hpos(machine->primary_screen), (display_counter + 1) / NEOGEO_HTOTAL, (display_counter + 1) % NEOGEO_HTOTAL);
timer_adjust_oneshot(display_position_interrupt_timer, period, 0);
}
}
