// license:BSD-3-Clause
// copyright-holders:Wilbert Pol
/**********************************************************************

    Motorola MC6845 and compatible CRT controller emulation

    The following variations exist that are different in
    functionality and not just in speed rating(1):
        * Motorola 6845, 6845-1
        * Hitachi 46505
        * Rockwell 6545, 6545-1 (= Synertek SY6545-1)
        * MOS Technology 6545-1

    (1) as per the document at
    http://www.6502.org/users/andre/hwinfo/crtc/diffs.html

    The various speed rated devices are identified by a letter,
    for example M68A45, M68B45, etc.

    The chip is originally designed by Hitachi, not by Motorola.

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

/*

    TODO:

    - Change device video emulation x/y offsets when "show border color"
      is true
    - Support 'interlace and video' mode

    - mos8563

        - horizontal scroll
        - vertical scroll
        - bitmap modes
        - display enable begin/end

*/

#include "emu.h"
#include "mc6845.h"


#define LOG     (0)


const device_type MC6845 = &device_creator<mc6845_device>;
const device_type MC6845_1 = &device_creator<mc6845_1_device>;
const device_type R6545_1 = &device_creator<r6545_1_device>;
const device_type C6545_1 = &device_creator<c6545_1_device>;
const device_type H46505 = &device_creator<h46505_device>;
const device_type HD6845 = &device_creator<hd6845_device>;
const device_type SY6545_1 = &device_creator<sy6545_1_device>;
const device_type SY6845E = &device_creator<sy6845e_device>;
const device_type HD6345 = &device_creator<hd6345_device>;
const device_type AMS40041 = &device_creator<ams40041_device>;
const device_type AMS40489 = &device_creator<ams40489_device>;
const device_type MOS8563 = &device_creator<mos8563_device>;
const device_type MOS8568 = &device_creator<mos8568_device>;


/* mode macros */
#define MODE_TRANSPARENT            ((m_mode_control & 0x08) != 0)
#define MODE_TRANSPARENT_PHI2       ((m_mode_control & 0x88) == 0x88)
/* FIXME: not supported yet */
#define MODE_TRANSPARENT_BLANK      ((m_mode_control & 0x88) == 0x08)
#define MODE_UPDATE_STROBE          ((m_mode_control & 0x40) != 0)
#define MODE_CURSOR_SKEW            ((m_mode_control & 0x20) != 0)
#define MODE_DISPLAY_ENABLE_SKEW    ((m_mode_control & 0x10) != 0)
#define MODE_ROW_COLUMN_ADDRESSING  ((m_mode_control & 0x04) != 0)
#define MODE_INTERLACE_AND_VIDEO    ((m_mode_control & 0x03) == 3)

#define VSS_CBRATE                  BIT(m_vert_scroll, 5)
#define VSS_RVS                     BIT(m_vert_scroll, 6)
#define VSS_COPY                    BIT(m_vert_scroll, 7)

#define HSS_DBL                     BIT(m_horiz_scroll, 4)
#define HSS_SEMI                    BIT(m_horiz_scroll, 5)
#define HSS_ATTR                    BIT(m_horiz_scroll, 6)
#define HSS_TEXT                    BIT(m_horiz_scroll, 7)

#define ATTR_COLOR                  (attr & 0x0f)
#define ATTR_BACKGROUND             (attr & 0x0f)
#define ATTR_FOREGROUND             (attr >> 4)
#define ATTR_BLINK                  BIT(attr, 4)
#define ATTR_UNDERLINE              BIT(attr, 5)
#define ATTR_REVERSE                BIT(attr, 6)
#define ATTR_ALTERNATE_CHARSET      BIT(attr, 7)


mc6845_device::mc6845_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source)
	: device_t(mconfig, type, name, tag, owner, clock, shortname, source),
		device_video_interface(mconfig, *this, false),
		m_show_border_area(true),
		m_interlace_adjust(0),
		m_visarea_adjust_min_x(0),
		m_visarea_adjust_max_x(0),
		m_visarea_adjust_min_y(0),
		m_visarea_adjust_max_y(0),
		m_hpixels_per_column(0),
		m_out_de_cb(*this),
		m_out_cur_cb(*this),
		m_out_hsync_cb(*this),
		m_out_vsync_cb(*this)
{
}

mc6845_device::mc6845_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: device_t(mconfig, MC6845, "MC6845 CRTC", tag, owner, clock, "mc6845", __FILE__),
		device_video_interface(mconfig, *this, false),
		m_show_border_area(true),
		m_interlace_adjust(0),
		m_visarea_adjust_min_x(0),
		m_visarea_adjust_max_x(0),
		m_visarea_adjust_min_y(0),
		m_visarea_adjust_max_y(0),
		m_hpixels_per_column(0),
		m_out_de_cb(*this),
		m_out_cur_cb(*this),
		m_out_hsync_cb(*this),
		m_out_vsync_cb(*this)
{
}


void mc6845_device::device_post_load()
{
	recompute_parameters(true);
}


void mc6845_device::call_on_update_address(int strobe)
{
	if (!m_on_update_addr_changed_cb.isnull())
		m_upd_trans_timer->adjust(attotime::zero, (m_update_addr << 8) | strobe);
	else
		fatalerror("M6845: transparent memory mode without handler\n");
}


WRITE8_MEMBER( mc6845_device::address_w )
{
	m_register_address_latch = data & 0x1f;
}


READ8_MEMBER( mc6845_device::status_r )
{
	UINT8 ret = 0;

	/* VBLANK bit */
	if (m_supports_status_reg_d5 && !m_line_enable_ff)
		ret = ret | 0x20;

	/* light pen latched */
	if (m_supports_status_reg_d6 && m_light_pen_latched)
		ret = ret | 0x40;

	/* UPDATE ready */
	if (m_supports_status_reg_d7 && m_update_ready_bit)
		ret = ret | 0x80;

	return ret;
}


READ8_MEMBER( mc6845_device::register_r )
{
	UINT8 ret = 0;

	switch (m_register_address_latch)
	{
		case 0x0c:  ret = m_supports_disp_start_addr_r ? (m_disp_start_addr >> 8) & 0xff : 0; break;
		case 0x0d:  ret = m_supports_disp_start_addr_r ? (m_disp_start_addr >> 0) & 0xff : 0; break;
		case 0x0e:  ret = (m_cursor_addr    >> 8) & 0xff; break;
		case 0x0f:  ret = (m_cursor_addr    >> 0) & 0xff; break;
		case 0x10:  ret = (m_light_pen_addr >> 8) & 0xff; m_light_pen_latched = false; break;
		case 0x11:  ret = (m_light_pen_addr >> 0) & 0xff; m_light_pen_latched = false; break;
		case 0x1f:
			if (m_supports_transparent && MODE_TRANSPARENT)
			{
				if(MODE_TRANSPARENT_PHI2)
				{
					m_update_addr++;
					m_update_addr &= 0x3fff;
					call_on_update_address(0);
				}
				else
				{
					/* MODE_TRANSPARENT_BLANK */
					if(m_update_ready_bit)
					{
						m_update_ready_bit = false;
						update_upd_adr_timer();
					}
				}
			}
			break;

		/* all other registers are write only and return 0 */
		default: break;
	}

	return ret;
}


WRITE8_MEMBER( mc6845_device::register_w )
{
	if (LOG)  logerror("%s:M6845 reg 0x%02x = 0x%02x\n", machine().describe_context(), m_register_address_latch, data);

	switch (m_register_address_latch)
	{
		case 0x00:  m_horiz_char_total =   data & 0xff; break;
		case 0x01:  m_horiz_disp       =   data & 0xff; break;
		case 0x02:  m_horiz_sync_pos   =   data & 0xff; break;
		case 0x03:  m_sync_width       =   data & 0xff; break;
		case 0x04:  m_vert_char_total  =   data & 0x7f; break;
		case 0x05:  m_vert_total_adj   =   data & 0x1f; break;
		case 0x06:  m_vert_disp        =   data & 0x7f; break;
		case 0x07:  m_vert_sync_pos    =   data & 0x7f; break;
		case 0x08:  m_mode_control     =   data & 0xff; break;
		case 0x09:  m_max_ras_addr     =   data & 0x1f; break;
		case 0x0a:  m_cursor_start_ras =   data & 0x7f; break;
		case 0x0b:  m_cursor_end_ras   =   data & 0x1f; break;
		case 0x0c:  m_disp_start_addr  = ((data & 0x3f) << 8) | (m_disp_start_addr & 0x00ff); break;
		case 0x0d:  m_disp_start_addr  = ((data & 0xff) << 0) | (m_disp_start_addr & 0xff00); break;
		case 0x0e:  m_cursor_addr      = ((data & 0x3f) << 8) | (m_cursor_addr & 0x00ff); break;
		case 0x0f:  m_cursor_addr      = ((data & 0xff) << 0) | (m_cursor_addr & 0xff00); break;
		case 0x10: /* read-only */ break;
		case 0x11: /* read-only */ break;
		case 0x12:
			if (m_supports_transparent)
			{
				m_update_addr = ((data & 0x3f) << 8) | (m_update_addr & 0x00ff);
				if(MODE_TRANSPARENT_PHI2)
					call_on_update_address(0);
			}
			break;
		case 0x13:
			if (m_supports_transparent)
			{
				m_update_addr = ((data & 0xff) << 0) | (m_update_addr & 0xff00);
				if(MODE_TRANSPARENT_PHI2)
					call_on_update_address(0);
			}
			break;
		case 0x1f:
			if (m_supports_transparent && MODE_TRANSPARENT)
			{
				if(MODE_TRANSPARENT_PHI2)
				{
					m_update_addr++;
					m_update_addr &= 0x3fff;
					call_on_update_address(0);
				}
				else
				{
					/* MODE_TRANSPARENT_BLANK */
					if(m_update_ready_bit)
					{
						m_update_ready_bit = false;
						update_upd_adr_timer();
					}
				}
			}
			break;
		default: break;
	}

	/* display message if the Mode Control register is not zero */
	if ((m_register_address_latch == 0x08) && (m_mode_control != 0))
		if (!m_supports_transparent)
			logerror("M6845: Mode Control %02X is not supported!!!\n", m_mode_control);

	recompute_parameters(false);
}


WRITE8_MEMBER( mos8563_device::address_w )
{
	m_register_address_latch = data & 0x3f;
}


READ8_MEMBER( mos8563_device::status_r )
{
	UINT8 ret = m_revision;

	/* VBLANK bit */
	if (!m_line_enable_ff)
		ret = ret | 0x20;

	/* light pen latched */
	if (m_light_pen_latched)
		ret = ret | 0x40;

	/* UPDATE ready */
	if (m_update_ready_bit)
		ret = ret | 0x80;

	return ret;
}


READ8_MEMBER( mos8563_device::register_r )
{
	UINT8 ret = 0xff;

	switch (m_register_address_latch)
	{
		case 0x00:  ret = m_horiz_char_total; break;
		case 0x01:  ret = m_horiz_disp; break;
		case 0x02:  ret = m_horiz_sync_pos; break;
		case 0x03:  ret = m_sync_width; break;
		case 0x04:  ret = m_vert_char_total; break;
		case 0x05:  ret = m_vert_total_adj | 0xc0; break;
		case 0x06:  ret = m_vert_disp; break;
		case 0x07:  ret = m_vert_sync_pos; break;
		case 0x08:  ret = m_mode_control | 0xfc; break;
		case 0x09:  ret = m_max_ras_addr | 0xe0; break;
		case 0x0a:  ret = m_cursor_start_ras | 0x80; break;
		case 0x0b:  ret = m_cursor_end_ras | 0xe0; break;
		case 0x0c:  ret = (m_disp_start_addr >> 8) & 0xff; break;
		case 0x0d:  ret = (m_disp_start_addr >> 0) & 0xff; break;
		case 0x0e:  ret = (m_cursor_addr     >> 8) & 0xff; break;
		case 0x0f:  ret = (m_cursor_addr     >> 0) & 0xff; break;
		case 0x10:  ret = (m_light_pen_addr  >> 8) & 0xff; m_light_pen_latched = false; break;
		case 0x11:  ret = (m_light_pen_addr  >> 0) & 0xff; m_light_pen_latched = false; break;
		case 0x12:  ret = (m_update_addr     >> 8) & 0xff; break;
		case 0x13:  ret = (m_update_addr     >> 0) & 0xff; break;
		case 0x14:  ret = (m_attribute_addr  >> 8) & 0xff; break;
		case 0x15:  ret = (m_attribute_addr  >> 0) & 0xff; break;
		case 0x16:  ret = m_horiz_char; break;
		case 0x17:  ret = m_vert_char_disp | 0xe0; break;
		case 0x18:  ret = m_vert_scroll; break;
		case 0x19:  ret = m_horiz_scroll; break;
		case 0x1a:  ret = m_color; break;
		case 0x1b:  ret = m_row_addr_incr; break;
		case 0x1c:  ret = m_char_base_addr | 0x1f; break;
		case 0x1d:  ret = m_underline_ras | 0xe0; break;
		case 0x1e:  ret = m_word_count; break;
		case 0x1f:  ret = read_videoram(m_update_addr++); break;
		case 0x20:  ret = (m_block_addr      >> 8) & 0xff; break;
		case 0x21:  ret = (m_block_addr      >> 0) & 0xff; break;
		case 0x22:  ret = (m_de_begin        >> 8) & 0xff; break;
		case 0x23:  ret = (m_de_begin        >> 0) & 0xff; break;
		case 0x24:  ret = m_dram_refresh | 0xf0; break;
		case 0x25:  ret = m_sync_polarity | 0x3f; break;
	}

	return ret;
}


WRITE8_MEMBER( mos8563_device::register_w )
{
	if (LOG)  logerror("%s:MOS8563 reg 0x%02x = 0x%02x\n", machine().describe_context(), m_register_address_latch, data);

	switch (m_register_address_latch)
	{
		case 0x00:  m_horiz_char_total =   data & 0xff; break;
		case 0x01:  m_horiz_disp       =   data & 0xff; break;
		case 0x02:  m_horiz_sync_pos   =   data & 0xff; break;
		case 0x03:  m_sync_width       =   data & 0xff; break;
		case 0x04:  m_vert_char_total  =   data & 0xff; break;
		case 0x05:  m_vert_total_adj   =   data & 0x1f; break;
		case 0x06:  m_vert_disp        =   data & 0xff; break;
		case 0x07:  m_vert_sync_pos    =   data & 0xff; break;
		case 0x08:  m_mode_control     =   data & 0x03; break;
		case 0x09:  m_max_ras_addr     =   data & 0x1f; break;
		case 0x0a:  m_cursor_start_ras =   data & 0x7f; break;
		case 0x0b:  m_cursor_end_ras   =   data & 0x1f; break;
		case 0x0c:  m_disp_start_addr  = ((data & 0xff) << 8) | (m_disp_start_addr & 0x00ff); break;
		case 0x0d:  m_disp_start_addr  = ((data & 0xff) << 0) | (m_disp_start_addr & 0xff00); break;
		case 0x0e:  m_cursor_addr      = ((data & 0xff) << 8) | (m_cursor_addr & 0x00ff); break;
		case 0x0f:  m_cursor_addr      = ((data & 0xff) << 0) | (m_cursor_addr & 0xff00); break;
		case 0x10: /* read-only */ break;
		case 0x11: /* read-only */ break;
		case 0x12:  m_update_addr      = ((data & 0xff) << 8) | (m_update_addr & 0x00ff); break;
		case 0x13:  m_update_addr      = ((data & 0xff) << 0) | (m_update_addr & 0xff00); break;
		case 0x14:  m_attribute_addr   = ((data & 0xff) << 8) | (m_attribute_addr & 0x00ff); break;
		case 0x15:  m_attribute_addr   = ((data & 0xff) << 0) | (m_attribute_addr & 0xff00); break;
		case 0x16:  m_horiz_char       =   data & 0xff; break;
		case 0x17:  m_vert_char_disp   =   data & 0x1f; break;
		case 0x18:  m_vert_scroll      =   data & 0xff; break;
		case 0x19:
			{
			int dbl = HSS_DBL;
			m_horiz_scroll = data & 0xff;
			if (dbl && !HSS_DBL) set_clock(m_clock << 1);
			if (!dbl && HSS_DBL) set_clock(m_clock >> 1);
			break;
			}
		case 0x1a:  m_color            =   data & 0xff; break;
		case 0x1b:  m_row_addr_incr    =   data & 0xff; break;
		case 0x1c:  m_char_base_addr   =   data & 0xe0; break;
		case 0x1d:  m_underline_ras    =   data & 0x1f; break;
		case 0x1e:
			m_word_count = data & 0xff;
			m_update_ready_bit = 0;
			m_block_copy_timer->adjust( attotime::from_ticks( 1, m_clock ) );
			break;
		case 0x1f:
			m_data = data & 0xff;
			write_videoram(m_update_addr++, m_data);
			break;
		case 0x20:  m_block_addr       = ((data & 0xff) << 8) | (m_block_addr & 0x00ff); break;
		case 0x21:  m_block_addr       = ((data & 0xff) << 0) | (m_block_addr & 0xff00); break;
		case 0x22:  m_de_begin         = ((data & 0xff) << 8) | (m_de_begin & 0x00ff); break;
		case 0x23:  m_de_begin         = ((data & 0xff) << 0) | (m_de_begin & 0xff00); break;
		case 0x24:  m_dram_refresh     =   data & 0x0f; break;
		case 0x25:  m_sync_polarity    =   data & 0xc0; break;
	}

	recompute_parameters(false);
}


inline UINT8 mos8563_device::read_videoram(offs_t offset)
{
	return space(AS_0).read_byte(offset);
}

inline void mos8563_device::write_videoram(offs_t offset, UINT8 data)
{
	space(AS_0).write_byte(offset, data);
}


READ_LINE_MEMBER( mc6845_device::de_r )
{
	return m_de;
}


READ_LINE_MEMBER( mc6845_device::cursor_r )
{
	return m_cur;
}


READ_LINE_MEMBER( mc6845_device::hsync_r )
{
	return m_hsync;
}


READ_LINE_MEMBER( mc6845_device::vsync_r )
{
	return m_vsync;
}


void mc6845_device::recompute_parameters(bool postload)
{
	UINT16 hsync_on_pos, hsync_off_pos, vsync_on_pos, vsync_off_pos;

	UINT16 video_char_height = m_max_ras_addr + (MODE_INTERLACE_AND_VIDEO ? m_interlace_adjust : m_noninterlace_adjust);   // fix garbage at the bottom of the screen (eg victor9k)
	// Would be useful for 'interlace and video' mode support...
	// UINT16 frame_char_height = (MODE_INTERLACE_AND_VIDEO ? m_max_ras_addr / 2 : m_max_ras_addr) + 1;

	/* compute the screen sizes */
	UINT16 horiz_pix_total = (m_horiz_char_total + 1) * m_hpixels_per_column;
	UINT16 vert_pix_total = (m_vert_char_total + 1) * video_char_height + m_vert_total_adj;

	/* determine the visible area, avoid division by 0 */
	UINT16 max_visible_x = m_horiz_disp * m_hpixels_per_column - 1;
	UINT16 max_visible_y = m_vert_disp * video_char_height - 1;

	/* determine the syncing positions */
	UINT8 horiz_sync_char_width = m_sync_width & 0x0f;
	UINT8 vert_sync_pix_width = m_supports_vert_sync_width ? (m_sync_width >> 4) & 0x0f : 0x10;

	if (horiz_sync_char_width == 0)
		horiz_sync_char_width = 0x10;

	if (vert_sync_pix_width == 0)
		vert_sync_pix_width = 0x10;

	/* determine the transparent update cycle time, 1 update every 4 character clocks */
	m_upd_time = attotime::from_hz(m_clock) * (4 * m_hpixels_per_column);

	hsync_on_pos = m_horiz_sync_pos * m_hpixels_per_column;
	hsync_off_pos = hsync_on_pos + (horiz_sync_char_width * m_hpixels_per_column);
	vsync_on_pos = m_vert_sync_pos * video_char_height;
	vsync_off_pos = vsync_on_pos + vert_sync_pix_width;

	// the Commodore PET computers have a non-standard 20kHz monitor which
	// requires a wider HSYNC pulse that extends past the scanline width
	if (hsync_off_pos > horiz_pix_total)
		hsync_off_pos = horiz_pix_total;

	if (vsync_on_pos > vert_pix_total)
		vsync_on_pos = vert_pix_total;

	if (vsync_off_pos > vert_pix_total)
		vsync_off_pos = vert_pix_total;

	/* update only if screen parameters changed, unless we are coming here after loading the saved state */
	if (postload ||
		(horiz_pix_total != m_horiz_pix_total) || (vert_pix_total != m_vert_pix_total) ||
		(max_visible_x != m_max_visible_x) || (max_visible_y != m_max_visible_y) ||
		(hsync_on_pos != m_hsync_on_pos) || (vsync_on_pos != m_vsync_on_pos) ||
		(hsync_off_pos != m_hsync_off_pos) || (vsync_off_pos != m_vsync_off_pos))
	{
		/* update the screen if we have valid data */
		if ((horiz_pix_total > 0) && (max_visible_x < horiz_pix_total) &&
			(vert_pix_total > 0) && (max_visible_y < vert_pix_total) &&
			(hsync_on_pos <= horiz_pix_total) && (vsync_on_pos <= vert_pix_total) &&
			(hsync_on_pos != hsync_off_pos))
		{
			rectangle visarea;

			attoseconds_t refresh = HZ_TO_ATTOSECONDS(m_clock) * (m_horiz_char_total + 1) * vert_pix_total;

			// This doubles the vertical resolution, required for 'interlace and video' mode support.
			// Tested and works for super80v, which was designed with this in mind (choose green or monochrome colour in config switches).
			// However it breaks some other drivers (apricot,a6809,victor9k,bbc(mode7)).
			// So, it is commented out for now.
			// Also, the mode-register change needs to be added to the changed-parameter tests above.
			if (MODE_INTERLACE_AND_VIDEO)
			{
				//max_visible_y *= 2;
				//vert_pix_total *= 2;
			}

			if(m_show_border_area)
				visarea.set(0, horiz_pix_total-2, 0, vert_pix_total-2);
			else
				visarea.set(0 + m_visarea_adjust_min_x, max_visible_x + m_visarea_adjust_max_x, 0 + m_visarea_adjust_min_y, max_visible_y + m_visarea_adjust_max_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));

			if ( m_screen != nullptr )
				m_screen->configure(horiz_pix_total, vert_pix_total, visarea, refresh);

			if(!m_reconfigure_cb.isnull())
				m_reconfigure_cb(horiz_pix_total, vert_pix_total, visarea, refresh);

			m_has_valid_parameters = true;
		}
		else
			m_has_valid_parameters = false;

		m_horiz_pix_total = horiz_pix_total;
		m_vert_pix_total = vert_pix_total;
		m_max_visible_x = max_visible_x;
		m_max_visible_y = max_visible_y;
		m_hsync_on_pos = hsync_on_pos;
		m_hsync_off_pos = hsync_off_pos;
		m_vsync_on_pos = vsync_on_pos;
		m_vsync_off_pos = vsync_off_pos;
		if (!postload) // set m_line_counter to 0 on normal operation, but not on postload
			m_line_counter = 0;
	}
}


void mc6845_device::update_counters()
{
	m_character_counter = m_line_timer->elapsed( ).as_ticks( m_clock );

	if ( m_hsync_off_timer ->enabled( ) )
	{
		m_hsync_width_counter = m_hsync_off_timer ->elapsed( ).as_ticks( m_clock );
	}
}


void mc6845_device::set_de(int state)
{
	if (m_de != state)
	{
		m_de = state;

		if (m_de)
		{
			/* If the upd_adr_timer was running, cancel it */
			m_upd_adr_timer->adjust(attotime::never);
		}
		else
		{
			/* if transparent update was requested fire the update timer */
			if(!m_update_ready_bit)
				update_upd_adr_timer();
		}

		m_out_de_cb(m_de);
	}
}


void mc6845_device::set_hsync(int state)
{
	if (m_hsync != state)
	{
		m_hsync = state;
		m_out_hsync_cb(m_hsync);
	}
}


void mc6845_device::set_vsync(int state)
{
	if (m_vsync != state)
	{
		m_vsync = state;
		m_out_vsync_cb(m_vsync);
	}
}


void mc6845_device::set_cur(int state)
{
	if (m_cur != state)
	{
		m_cur = state;
		m_out_cur_cb(m_cur);
	}
}


void mc6845_device::update_upd_adr_timer()
{
	if (! m_de && m_supports_transparent)
		m_upd_adr_timer->adjust(m_upd_time);
}


void mc6845_device::handle_line_timer()
{
	int new_vsync = m_vsync;

	m_character_counter = 0;
	m_cursor_x = -1;

	/* Check if VSYNC is active */
	if ( m_vsync_ff )
	{
		UINT8 vsync_width = m_supports_vert_sync_width ? (m_sync_width >> 4) & 0x0f : 0;

		m_vsync_width_counter = ( m_vsync_width_counter + 1 ) & 0x0F;

		/* Check if we've reached end of VSYNC */
		if ( m_vsync_width_counter == vsync_width )
		{
			m_vsync_ff = 0;

			new_vsync = FALSE;
		}
	}

	// For rudimentary 'interlace and video' support, m_raster_counter increments by 1 rather than the correct 2.
	// The correct test would be:
	// if ( m_raster_counter == (MODE_INTERLACE_AND_VIDEO ? m_max_ras_addr + 1 : m_max_ras_addr) )
	if ( m_raster_counter == m_max_ras_addr + (MODE_INTERLACE_AND_VIDEO ? m_interlace_adjust : m_noninterlace_adjust) - 1 )
	{
		/* Check if we have reached the end of the vertical area */
		if ( m_line_counter == m_vert_char_total )
		{
			m_adjust_counter = 0;
			m_adjust_active = 1;
		}

		m_raster_counter = 0;
		m_line_counter = ( m_line_counter + 1 ) & 0x7F;
		m_line_address = ( m_line_address + m_horiz_disp ) & 0x3fff;

		/* Check if we've reached the end of active display */
		if ( m_line_counter == m_vert_disp )
		{
			m_line_enable_ff = false;
			m_current_disp_addr = m_disp_start_addr;
		}

		/* Check if VSYNC should be enabled */
		if ( m_line_counter == m_vert_sync_pos )
		{
			m_vsync_width_counter = 0;
			m_vsync_ff = 1;

			new_vsync = TRUE;
		}
	}
	else
	{
		// For rudimentary 'interlace and video' support, m_raster_counter increments by 1 rather than the correct 2.
		// m_raster_counter = ( m_raster_counter + (MODE_INTERLACE_AND_VIDEO ? 2 : 1) ) & 0x1F;
		m_raster_counter = ( m_raster_counter + 1 ) & 0x1F;
	}

	if ( m_adjust_active )
	{
		/* Check if we have reached the end of a full cycle */
		if ( m_adjust_counter == m_vert_total_adj )
		{
			m_adjust_active = 0;
			m_raster_counter = 0;
			m_line_counter = 0;
			m_line_address = m_disp_start_addr;
			m_line_enable_ff = true;
			/* also update the cursor state now */
			update_cursor_state();

			if (m_screen != nullptr)
				m_screen->reset_origin();
		}
		else
		{
			m_adjust_counter = ( m_adjust_counter + 1 ) & 0x1F;
		}
	}

	if ( m_line_enable_ff )
	{
		/* Schedule DE off signal change */
		m_de_off_timer->adjust(attotime::from_ticks( m_horiz_disp, m_clock ));

		/* Is cursor visible on this line? */
		if ( m_cursor_state &&
			(m_raster_counter >= (m_cursor_start_ras & 0x1f)) &&
			(m_raster_counter <= m_cursor_end_ras) &&
			(m_cursor_addr >= m_line_address) &&
			(m_cursor_addr < (m_line_address + m_horiz_disp)) )
		{
			m_cursor_x = m_cursor_addr - m_line_address;

			/* Schedule CURSOR ON signal */
			m_cur_on_timer->adjust( attotime::from_ticks( m_cursor_x, m_clock ) );
		}
	}

	/* Schedule HSYNC on signal */
	m_hsync_on_timer->adjust( attotime::from_ticks( m_horiz_sync_pos, m_clock ) );

	/* Schedule our next callback */
	m_line_timer->adjust( attotime::from_ticks( m_horiz_char_total + 1, m_clock ) );

	/* Set VSYNC and DE signals */
	set_vsync( new_vsync );
	set_de( m_line_enable_ff ? TRUE : FALSE );
}


void mc6845_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	switch (id)
	{
	case TIMER_LINE:
		handle_line_timer();
		break;

	case TIMER_DE_OFF:
		set_de( FALSE );
		break;

	case TIMER_CUR_ON:
		set_cur( TRUE );

		/* Schedule CURSOR off signal */
		m_cur_off_timer->adjust( attotime::from_ticks( 1, m_clock ) );
		break;

	case TIMER_CUR_OFF:
		set_cur( FALSE );
		break;

	case TIMER_HSYNC_ON:
		{
			UINT8 hsync_width = ( m_sync_width & 0x0f ) ? ( m_sync_width & 0x0f ) : 0x10;

			m_hsync_width_counter = 0;
			set_hsync( TRUE );

			/* Schedule HSYNC off signal */
			m_hsync_off_timer->adjust( attotime::from_ticks( hsync_width, m_clock ) );
		}
		break;

	case TIMER_HSYNC_OFF:
		set_hsync( FALSE );
		break;

	case TIMER_LIGHT_PEN_LATCH:
		m_light_pen_addr = get_ma();
		m_light_pen_latched = true;
		break;

	case TIMER_UPD_ADR:
		/* fire a update address strobe */
		call_on_update_address(0);
		break;

	case TIMER_UPD_TRANS:
		{
			int addr = (param >> 8);
			int strobe = (param & 0xff);

			/* call the callback function -- we know it exists */
			m_on_update_addr_changed_cb(addr, strobe);

			if(!m_update_ready_bit && MODE_TRANSPARENT_BLANK)
			{
				m_update_addr++;
				m_update_addr &= 0x3fff;
				m_update_ready_bit = true;
			}
		}
		break;

	}
}


void mos8563_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
{
	switch (id)
	{
	case TIMER_BLOCK_COPY:
	{
		UINT8 data = VSS_COPY ? read_videoram(m_block_addr++) : m_data;

		write_videoram(m_update_addr++, data);

		if (--m_word_count)
		{
			m_block_copy_timer->adjust( attotime::from_ticks( 1, m_clock ) );
		}
		else
		{
			m_update_ready_bit = 1;
		}
		break;
	}
	default:
		mc6845_device::device_timer(timer, id, param, ptr);
		break;
	}
}


UINT16 mc6845_device::get_ma()
{
	update_counters();

	return ( m_line_address + m_character_counter ) & 0x3fff;
}


UINT8 mc6845_device::get_ra()
{
	return m_raster_counter;
}


void mc6845_device::assert_light_pen_input()
{
	/* compute the pixel coordinate of the NEXT character -- this is when the light pen latches */
	/* set the timer that will latch the display address into the light pen registers */
	m_light_pen_latch_timer->adjust(attotime::from_ticks( 1, m_clock ));
}


void mc6845_device::set_clock(int clock)
{
	/* validate arguments */
	assert(clock > 0);

	if (clock != m_clock)
	{
		m_clock = clock;
		recompute_parameters(true);
	}
}


void mc6845_device::set_hpixels_per_column(int hpixels_per_column)
{
	/* validate arguments */
	assert(hpixels_per_column > 0);

	if (hpixels_per_column != m_hpixels_per_column)
	{
		m_hpixels_per_column = hpixels_per_column;
		recompute_parameters(false);
	}
}


void mc6845_device::update_cursor_state()
{
	/* save and increment cursor counter */
	UINT8 last_cursor_blink_count = m_cursor_blink_count;
	m_cursor_blink_count = m_cursor_blink_count + 1;

	/* switch on cursor blinking mode */
	switch (m_cursor_start_ras & 0x60)
	{
		/* always on */
		case 0x00: m_cursor_state = true; break;

		/* always off */
		default:
		case 0x20: m_cursor_state = false; break;

		/* fast blink */
		case 0x40:
			if ((last_cursor_blink_count & 0x10) != (m_cursor_blink_count & 0x10))
				m_cursor_state = !m_cursor_state;
			break;

		/* slow blink */
		case 0x60:
			if ((last_cursor_blink_count & 0x20) != (m_cursor_blink_count & 0x20))
				m_cursor_state = !m_cursor_state;
			break;
	}
}


UINT8 mc6845_device::draw_scanline(int y, bitmap_rgb32 &bitmap, const rectangle &cliprect)
{
	/* compute the current raster line */
	UINT8 ra = y % (m_max_ras_addr + (MODE_INTERLACE_AND_VIDEO ? m_interlace_adjust : m_noninterlace_adjust));

	/* check if the cursor is visible and is on this scanline */
	int cursor_visible = m_cursor_state &&
						(ra >= (m_cursor_start_ras & 0x1f)) &&
						(ra <= m_cursor_end_ras) &&
						(m_cursor_addr >= m_current_disp_addr) &&
						(m_cursor_addr < (m_current_disp_addr + m_horiz_disp));

	/* compute the cursor X position, or -1 if not visible */
	INT8 cursor_x = cursor_visible ? (m_cursor_addr - m_current_disp_addr) : -1;
	int de = (y < m_max_visible_y) ? 1 : 0;
	int vbp = m_vert_pix_total - m_vsync_off_pos;
	if (vbp < 0) vbp = 0;
	int hbp = m_horiz_pix_total - m_hsync_off_pos;
	if (hbp < 0) hbp = 0;

	/* call the external system to draw it */
	if (MODE_ROW_COLUMN_ADDRESSING)
	{
		UINT8 cc = 0;
		UINT8 cr = y / (m_max_ras_addr + (MODE_INTERLACE_AND_VIDEO ? m_interlace_adjust : m_noninterlace_adjust));
		UINT16 ma = (cr << 8) | cc;

		m_update_row_cb(bitmap, cliprect, ma, ra, y, m_horiz_disp, cursor_x, de, hbp, vbp);
	}
	else
	{
		m_update_row_cb(bitmap, cliprect, m_current_disp_addr, ra, y, m_horiz_disp, cursor_x, de, hbp, vbp);
	}

	/* update MA if the last raster address */
	if (ra == m_max_ras_addr + (MODE_INTERLACE_AND_VIDEO ? m_interlace_adjust : m_noninterlace_adjust) - 1)
		m_current_disp_addr = (m_current_disp_addr + m_horiz_disp) & 0x3fff;

	return ra;
}


UINT32 mc6845_device::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
{
	assert(bitmap.valid());

	if (m_has_valid_parameters)
	{
		assert(!m_update_row_cb.isnull());

		/* call the set up function if any */
		if (!m_begin_update_cb.isnull())
			m_begin_update_cb(bitmap, cliprect);

		if (cliprect.min_y == 0)
		{
			/* read the start address at the beginning of the frame */
			m_current_disp_addr = m_disp_start_addr;
		}

		/* for each row in the visible region */
		for (UINT16 y = cliprect.min_y; y <= cliprect.max_y; y++)
		{
			this->draw_scanline(y, bitmap, cliprect);
		}

		/* call the tear down function if any */
		if (!m_end_update_cb.isnull())
			m_end_update_cb(bitmap, cliprect);
	}
	else
	{
		if (LOG)  logerror("M6845: Invalid screen parameters - display disabled!!!\n");
	}

	return 0;
}


void mc6845_device::device_start()
{
	assert(m_clock > 0);
	assert(m_hpixels_per_column > 0);

	/* resolve callbacks */
	m_out_de_cb.resolve_safe();
	m_out_cur_cb.resolve_safe();
	m_out_hsync_cb.resolve_safe();
	m_out_vsync_cb.resolve_safe();

	/* bind delegates */
	m_reconfigure_cb.bind_relative_to(*owner());
	m_begin_update_cb.bind_relative_to(*owner());
	m_update_row_cb.bind_relative_to(*owner());
	m_end_update_cb.bind_relative_to(*owner());
	m_on_update_addr_changed_cb.bind_relative_to(*owner());

	/* create the timers */
	m_line_timer = timer_alloc(TIMER_LINE);
	m_de_off_timer = timer_alloc(TIMER_DE_OFF);
	m_cur_on_timer = timer_alloc(TIMER_CUR_ON);
	m_cur_off_timer = timer_alloc(TIMER_CUR_OFF);
	m_hsync_on_timer = timer_alloc(TIMER_HSYNC_ON);
	m_hsync_off_timer = timer_alloc(TIMER_HSYNC_OFF);
	m_light_pen_latch_timer = timer_alloc(TIMER_LIGHT_PEN_LATCH);
	m_upd_adr_timer = timer_alloc(TIMER_UPD_ADR);
	m_upd_trans_timer = timer_alloc(TIMER_UPD_TRANS);

	/* Use some large startup values */
	m_horiz_char_total = 0xff;
	m_max_ras_addr = 0x1f;
	m_vert_char_total = 0x7f;

	m_supports_disp_start_addr_r = false;  // MC6845 can not read Display Start (double checked on datasheet)
	m_supports_vert_sync_width = false;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
	m_has_valid_parameters = false;
	m_line_enable_ff = false;
	m_vsync_ff = 0;
	m_raster_counter = 0;
	m_adjust_active = 0;
	m_horiz_sync_pos = 1;
	m_vert_sync_pos = 1;
	m_de = 0;
	m_sync_width = 1;
	m_horiz_pix_total = m_vert_pix_total = 0;
	m_max_visible_x = m_max_visible_y = 0;
	m_hsync_on_pos = m_vsync_on_pos = 0;
	m_hsync_off_pos = m_vsync_off_pos = 0;
	m_vsync = m_hsync = 0;
	m_cur = 0;
	m_line_counter = 0;
	m_horiz_disp = m_vert_disp = 0;
	m_vert_sync_pos = 0;
	m_vert_total_adj = 0;
	m_cursor_start_ras = m_cursor_end_ras = m_cursor_addr = 0;
	m_cursor_blink_count = 0;
	m_cursor_state = 0;
	m_update_ready_bit = 0;
	m_line_address = 0;
	m_current_disp_addr = 0;
	m_disp_start_addr = 0;
	m_noninterlace_adjust = 1;
	m_interlace_adjust = 1;

	save_item(NAME(m_show_border_area));
	save_item(NAME(m_visarea_adjust_min_x));
	save_item(NAME(m_visarea_adjust_max_x));
	save_item(NAME(m_visarea_adjust_min_y));
	save_item(NAME(m_visarea_adjust_max_y));
	save_item(NAME(m_hpixels_per_column));
	save_item(NAME(m_register_address_latch));
	save_item(NAME(m_horiz_char_total));
	save_item(NAME(m_horiz_disp));
	save_item(NAME(m_horiz_sync_pos));
	save_item(NAME(m_sync_width));
	save_item(NAME(m_vert_char_total));
	save_item(NAME(m_vert_total_adj));
	save_item(NAME(m_vert_disp));
	save_item(NAME(m_vert_sync_pos));
	save_item(NAME(m_mode_control));
	save_item(NAME(m_max_ras_addr));
	save_item(NAME(m_cursor_start_ras));
	save_item(NAME(m_cursor_end_ras));
	save_item(NAME(m_disp_start_addr));
	save_item(NAME(m_cursor_addr));
	save_item(NAME(m_light_pen_addr));
	save_item(NAME(m_light_pen_latched));
	save_item(NAME(m_cursor_state));
	save_item(NAME(m_cursor_blink_count));
	save_item(NAME(m_update_addr));
	save_item(NAME(m_update_ready_bit));
	save_item(NAME(m_cur));
	save_item(NAME(m_hsync));
	save_item(NAME(m_vsync));
	save_item(NAME(m_de));
	save_item(NAME(m_character_counter));
	save_item(NAME(m_hsync_width_counter));
	save_item(NAME(m_line_counter));
	save_item(NAME(m_raster_counter));
	save_item(NAME(m_adjust_counter));
	save_item(NAME(m_vsync_width_counter));
	save_item(NAME(m_line_enable_ff));
	save_item(NAME(m_vsync_ff));
	save_item(NAME(m_adjust_active));
	save_item(NAME(m_line_address));
	save_item(NAME(m_cursor_x));
	save_item(NAME(m_has_valid_parameters));
}


void mc6845_1_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = true;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
}


void c6545_1_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
}


void r6545_1_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = true;
	m_supports_transparent = true;
}


void h46505_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = false;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
}


void hd6845_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = true;  // HD6845S can definitely read Display Start (double checked on datasheet)
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;

	// Non-interlace Mode, Interlace Sync Mode - When total number of rasters is RN, RN-1 shall be programmed.
	m_noninterlace_adjust = 1;
	// Interlace Sync & Video Mode - When total number of rasters is RN, RN-2 shall be programmed.
	m_interlace_adjust = 2;
}


void sy6545_1_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = true;
	m_supports_transparent = true;
}


void sy6845e_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = true;
	m_supports_transparent = true;
}


void hd6345_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = true;
	m_supports_vert_sync_width = true;
	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = true;
	m_supports_transparent = true;
}


void ams40041_device::device_start()
{
	mc6845_device::device_start();

	m_horiz_char_total =  113;
	m_horiz_disp       =  80;
	m_horiz_sync_pos   =  90;
	m_sync_width       =  10;
	m_vert_char_total  =  127;
	m_vert_total_adj   =  6;
	m_vert_disp        =  100;
	m_vert_sync_pos    =  112;
	m_mode_control     =  2;

	m_supports_disp_start_addr_r = false;
	m_supports_vert_sync_width = false;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
}

void ams40489_device::device_start()
{
	mc6845_device::device_start();

	m_supports_disp_start_addr_r = true;
	m_supports_vert_sync_width = false;
	m_supports_status_reg_d5 = false;
	m_supports_status_reg_d6 = false;
	m_supports_status_reg_d7 = false;
	m_supports_transparent = false;
}


void mos8563_device::device_start()
{
	mc6845_device::device_start();

	/* create the timers */
	m_block_copy_timer = timer_alloc(TIMER_BLOCK_COPY);

	m_supports_status_reg_d5 = true;
	m_supports_status_reg_d6 = true;
	m_supports_status_reg_d7 = true;
	m_update_ready_bit = 1;

	// default update_row delegate
	m_update_row_cb =  mc6845_update_row_delegate(FUNC(mos8563_device::vdc_update_row), this);

	m_char_blink_state = false;
	m_char_blink_count = 0;
	m_attribute_addr = 0;
	m_horiz_char = 0;
	m_vert_char_disp = 0;
	m_vert_scroll = 0;
	m_horiz_scroll = 0;
	m_color = 0;
	m_row_addr_incr = 0;
	m_char_base_addr = 0;
	m_underline_ras = 0;
	m_word_count = 0;
	m_data = 0;
	m_block_addr = 0;
	m_de_begin = 0;
	m_dram_refresh = 0;
	m_sync_polarity = 0;

	m_revision = 1;

	// initialize video RAM
	UINT8 data = 0xff;

	for (offs_t offset = 0; offset < 0x10000; offset++)
	{
		write_videoram(offset, data);
		data ^= 0xff;
	}

	save_item(NAME(m_char_buffer));
	save_item(NAME(m_attr_buffer));
	save_item(NAME(m_attribute_addr));
	save_item(NAME(m_horiz_char));
	save_item(NAME(m_vert_char_disp));
	save_item(NAME(m_vert_scroll));
	save_item(NAME(m_horiz_scroll));
	save_item(NAME(m_color));
	save_item(NAME(m_row_addr_incr));
	save_item(NAME(m_char_base_addr));
	save_item(NAME(m_underline_ras));
	save_item(NAME(m_word_count));
	save_item(NAME(m_data));
	save_item(NAME(m_block_addr));
	save_item(NAME(m_de_begin));
	save_item(NAME(m_dram_refresh));
	save_item(NAME(m_sync_polarity));
	save_item(NAME(m_revision));
}


void mos8568_device::device_start()
{
	mos8563_device::device_start();
}


void mc6845_device::device_reset()
{
	/* internal registers other than status remain unchanged, all outputs go low */
	m_out_de_cb(false);

	m_out_hsync_cb(false);

	m_out_vsync_cb(false);

	if (!m_line_timer->enabled())
		m_line_timer->adjust(attotime::from_ticks(m_horiz_char_total + 1, m_clock));

	m_light_pen_latched = false;

	m_cursor_addr = 0;
	m_line_address = 0;
	m_horiz_disp = 0;
	m_cursor_x = 0;
	m_mode_control = 0;
	m_register_address_latch = 0;
	m_update_addr = 0;
	m_light_pen_addr = 0;
}


void r6545_1_device::device_reset() { mc6845_device::device_reset(); }
void h46505_device::device_reset() { mc6845_device::device_reset(); }
void mc6845_1_device::device_reset() { mc6845_device::device_reset(); }
void hd6845_device::device_reset() { mc6845_device::device_reset(); }
void c6545_1_device::device_reset() { mc6845_device::device_reset(); }
void sy6545_1_device::device_reset() { mc6845_device::device_reset(); }
void sy6845e_device::device_reset() { mc6845_device::device_reset(); }
void hd6345_device::device_reset() { mc6845_device::device_reset(); }
void ams40041_device::device_reset() { mc6845_device::device_reset(); }
void ams40489_device::device_reset() { mc6845_device::device_reset(); }

void mos8563_device::device_reset()
{
	mc6845_device::device_reset();

	m_sync_polarity = 0xc0;
}

void mos8568_device::device_reset() { mos8563_device::device_reset(); }


//-------------------------------------------------
//  memory_space_config - return a description of
//  any address spaces owned by this device
//-------------------------------------------------

const address_space_config *mos8563_device::memory_space_config(address_spacenum spacenum) const
{
	switch (spacenum)
	{
		case AS_0: return &m_videoram_space_config;
		default: return nullptr;
	}
}

// default address maps
static ADDRESS_MAP_START( mos8563_videoram_map, AS_0, 8, mos8563_device )
	AM_RANGE(0x0000, 0xffff) AM_RAM
ADDRESS_MAP_END


r6545_1_device::r6545_1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, R6545_1, "R6545-1 CRTC", tag, owner, clock, "r6545_1", __FILE__)
{
}


h46505_device::h46505_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, H46505, "H46505 CRTC", tag, owner, clock, "h46505", __FILE__)
{
}


mc6845_1_device::mc6845_1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, MC6845_1, "MC6845-1 CRTC", tag, owner, clock, "mc6845_1", __FILE__)
{
}


hd6845_device::hd6845_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, HD6845, "HD6845 CRTC", tag, owner, clock, "hd6845", __FILE__)
{
}


c6545_1_device::c6545_1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, C6545_1, "C6545-1 CRTC", tag, owner, clock, "c6545_1", __FILE__)
{
}


sy6545_1_device::sy6545_1_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, SY6545_1, "SY6545-1 CRTC", tag, owner, clock, "sy6545_1", __FILE__)
{
}


sy6845e_device::sy6845e_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, SY6845E, "SY6845E CRTC", tag, owner, clock, "sy6845e", __FILE__)
{
}


hd6345_device::hd6345_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, HD6345, "HD6345 CRTC", tag, owner, clock, "hd6345", __FILE__)
{
}


ams40041_device::ams40041_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, AMS40041, "AMS40041 CRTC", tag, owner, clock, "ams40041", __FILE__)
{
}

ams40489_device::ams40489_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, AMS40489, "AMS40489 ASIC (CRTC)", tag, owner, clock, "ams40489", __FILE__)
{
}


mos8563_device::mos8563_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source)
	: mc6845_device(mconfig, type, name, tag, owner, clock, shortname, source),
		device_memory_interface(mconfig, *this),
		m_videoram_space_config("videoram", ENDIANNESS_LITTLE, 8, 16, 0, nullptr, *ADDRESS_MAP_NAME(mos8563_videoram_map)),
		m_palette(*this, "palette")
{
	set_clock_scale(1.0/8);
}


mos8563_device::mos8563_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mc6845_device(mconfig, MOS8563, "MOS8563", tag, owner, clock, "mos8563", __FILE__),
		device_memory_interface(mconfig, *this),
		m_videoram_space_config("videoram", ENDIANNESS_LITTLE, 8, 16, 0, nullptr, *ADDRESS_MAP_NAME(mos8563_videoram_map)),
		m_palette(*this, "palette")
{
	set_clock_scale(1.0/8);
}


mos8568_device::mos8568_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
	: mos8563_device(mconfig, MOS8568, "MOS8568", tag, owner, clock, "mos8568", __FILE__)
{
}


static MACHINE_CONFIG_FRAGMENT(mos8563)
	MCFG_PALETTE_ADD("palette", 16)
	MCFG_PALETTE_INIT_OWNER(mos8563_device, mos8563)
MACHINE_CONFIG_END

machine_config_constructor mos8563_device::device_mconfig_additions() const
{
		return MACHINE_CONFIG_NAME( mos8563 );
}


// VICE palette
PALETTE_INIT_MEMBER(mos8563_device, mos8563)
{
	palette.set_pen_color(0, rgb_t::black);
	palette.set_pen_color(1, rgb_t(0x55, 0x55, 0x55));
	palette.set_pen_color(2, rgb_t(0x00, 0x00, 0xaa));
	palette.set_pen_color(3, rgb_t(0x55, 0x55, 0xff));
	palette.set_pen_color(4, rgb_t(0x00, 0xaa, 0x00));
	palette.set_pen_color(5, rgb_t(0x55, 0xff, 0x55));
	palette.set_pen_color(6, rgb_t(0x00, 0xaa, 0xaa));
	palette.set_pen_color(7, rgb_t(0x55, 0xff, 0xff));
	palette.set_pen_color(8, rgb_t(0xaa, 0x00, 0x00));
	palette.set_pen_color(9, rgb_t(0xff, 0x55, 0x55));
	palette.set_pen_color(10, rgb_t(0xaa, 0x00, 0xaa));
	palette.set_pen_color(11, rgb_t(0xff, 0x55, 0xff));
	palette.set_pen_color(12, rgb_t(0xaa, 0x55, 0x00));
	palette.set_pen_color(13, rgb_t(0xff, 0xff, 0x55));
	palette.set_pen_color(14, rgb_t(0xaa, 0xaa, 0xaa));
	palette.set_pen_color(15, rgb_t::white);
}


void mos8563_device::update_cursor_state()
{
	mc6845_device::update_cursor_state();

	/* save and increment character blink counter */
	UINT8 last_char_blink_count = m_char_blink_count;
	m_char_blink_count++;

	/* switch on character blinking mode */
	if (VSS_CBRATE)
	{
		if ((last_char_blink_count & 0x20) != (m_char_blink_count & 0x20))
			m_char_blink_state = !m_char_blink_state;
	}
	else
	{
		if ((last_char_blink_count & 0x10) != (m_char_blink_count & 0x10))
			m_char_blink_state = !m_char_blink_state;
	}
}


UINT8 mos8563_device::draw_scanline(int y, bitmap_rgb32 &bitmap, const rectangle &cliprect)
{
	UINT8 ra = mc6845_device::draw_scanline(y, bitmap, cliprect);

	if (ra == m_max_ras_addr)
		m_current_disp_addr = (m_current_disp_addr + m_row_addr_incr) & 0x3fff;

	return ra;
}


MC6845_UPDATE_ROW( mos8563_device::vdc_update_row )
{
	const pen_t *pen = m_palette->pens();

	ra += (m_vert_scroll & 0x0f);
	ra &= 0x0f;

	UINT8 cth = (m_horiz_char >> 4) + (HSS_DBL ? 0 : 1);
	UINT8 cdh = (m_horiz_char & 0x0f) + (HSS_DBL ? 0 : 1);
	UINT8 cdv = m_vert_char_disp;

	for (int column = 0; column < x_count; column++)
	{
		UINT8 code = read_videoram(ma + column);
		UINT8 attr = 0;

		int fg = m_color >> 4;
		int bg = m_color & 0x0f;

		if (HSS_ATTR)
		{
			offs_t attr_addr = m_attribute_addr + ma + column;
			attr = read_videoram(attr_addr);
		}

		if (HSS_TEXT)
		{
			if (HSS_ATTR)
			{
				fg = ATTR_FOREGROUND;
				bg = ATTR_BACKGROUND;
			}

			if (VSS_RVS) code ^= 0xff;

			for (int bit = 0; bit < cdh; bit++)
			{
				int x = (m_horiz_scroll & 0x0f) - cth + (column * cth) + bit;
				if (x < 0) x = 0;
				int color = BIT(code, 7) ? fg : bg;

				bitmap.pix32(vbp + y, hbp + x) = pen[de ? color : 0];
			}
		}
		else
		{
			if (HSS_ATTR)
			{
				fg = ATTR_COLOR;
			}

			offs_t font_addr;

			if (m_max_ras_addr < 16)
			{
				font_addr = ((m_char_base_addr & 0xe0) << 8) | (ATTR_ALTERNATE_CHARSET << 12) | (code << 4) | (ra & 0x0f);
			}
			else
			{
				font_addr = ((m_char_base_addr & 0xc0) << 8) | (ATTR_ALTERNATE_CHARSET << 13) | (code << 5) | (ra & 0x1f);
			}

			UINT8 data = read_videoram(font_addr);

			if (ra >= cdv) data = 0;
			if (ATTR_UNDERLINE && (ra == m_underline_ras)) data = 0xff;
			if (ATTR_BLINK && !m_char_blink_state) data = 0;
			if (ATTR_REVERSE) data ^= 0xff;
			if (column == cursor_x) data ^= 0xff;
			if (VSS_RVS) data ^= 0xff;

			for (int bit = 0; bit < cdh; bit++)
			{
				int x = (m_horiz_scroll & 0x0f) - cth + (column * cth) + bit;
				if (x < 0) x = 0;
				int color = BIT(data, 7) ? fg : bg;

				bitmap.pix32(vbp + y, hbp + x) = pen[de ? color : 0];

				if ((bit < 8) || !HSS_SEMI) data <<= 1;
			}
		}
	}
}
