heathkit/h19.cpp, heathkit/tlb.cpp: Added Northwest Digital Systems GP-19 terminal (not working). (#11427)

New clones marked not working
--------------------------
Heath Company Heathkit H-19 w/ GP-19

src/emu/xtal.cpp

@@ -179,6 +179,7 @@ const double XTAL::known_xtals[] = {
 	 10'480'000, /* 10.48_MHz_XTAL         System-80 (50 Hz) */
 	 10'500'000, /* 10.5_MHz_XTAL          Agat-7 */
 	 10'595'000, /* 10.595_MHz_XTAL        Mad Alien */
+	 10'644'000, /* 10.644_MHz_XTAL        Northwest Digitial Systems GP-19 */
 	 10'644'500, /* 10.6445_MHz_XTAL       TRS-80 Model I */
 	 10'687'500, /* 10.6875_MHz_XTAL       BBC Bridge Companion */
 	 10'694'250, /* 10.69425_MHz_XTAL      Xerox 820 */
@@ -205,6 +206,7 @@ const double XTAL::known_xtals[] = {
 	 12'057'600, /* 12.0576_MHz_XTAL       Poly 1 (38400 * 314) */
 	 12'096'000, /* 12.096_MHz_XTAL        Some early 80's Atari games */
 	 12'288'000, /* 12.288_MHz_XTAL        Sega Model 3 digital audio board */
+	 12'292'000, /* 12.292_MHz_XTAL        Northwest Digitial Systems GP-19 */
 	 12'324'000, /* 12.324_MHz_XTAL        Otrona Attache */
 	 12'432'000, /* 12.432_MHz_XTAL        Kaneko Fly Boy/Fast Freddie Hardware */
 	 12'472'500, /* 12.4725_MHz_XTAL       Bonanza's Mini Boy 7 */
@@ -317,6 +319,7 @@ const double XTAL::known_xtals[] = {
 	 20'000'000, /* 20_MHz_XTAL            - */
 	 20'160'000, /* 20.16_MHz_XTAL         Nintendo 8080 */
 	 20'275'200, /* 20.2752_MHz_XTAL       TRS-80 Model III */
+	 20'282'000, /* 20.282_MHz_XTAL        Northwest Digitial Systems GP-19 */
 	 20'375'040, /* 20.37504_MHz_XTAL      Apple Lisa dot clock (197-0019A) */
 	 20'625'000, /* 20.625_MHz_XTAL        SM 7238 */
 	 20'790'000, /* 20.79_MHz_XTAL         Blockade-hardware Gremlin games */

src/mame/heathkit/h19.cpp

@@ -24,13 +24,19 @@ public:
 	{
 	}
 
+	// original h19
 	void h19(machine_config &config);
+
+	// replacement ROMs
 	void h19_superh19(machine_config &config);
 	void h19_watzh19(machine_config &config);
 	void h19_ultrah19(machine_config &config);
 
-private:
+	// add-on graphics boards
+	void h19_gp19(machine_config &config);
 
+
+private:
 	required_device<heath_tlb_device> m_tlb;
 
 };
@@ -55,6 +61,11 @@ void h19_state::h19_ultrah19(machine_config &config)
 	HEATH_ULTRA(config, m_tlb);
 }
 
+void h19_state::h19_gp19(machine_config &config)
+{
+	HEATH_GP19(config, m_tlb);
+}
+
 // ROM definition
 ROM_START( h19 )
 ROM_END
@@ -67,6 +78,10 @@ ROM_END
 
 ROM_START( ultra19 )
 ROM_END
+
+ROM_START( gp19 )
+ROM_END
+
 } // anonymous namespace
 
 //    YEAR  NAME     PARENT  COMPAT  MACHINE       INPUT   CLASS      INIT        COMPANY          FULLNAME                         FLAGS
@@ -77,3 +92,5 @@ COMP( 1982, super19, h19,    0,      h19_superh19,    0,   h19_state, empty_init
 COMP( 1982, watz19,  h19,    0,      h19_watzh19,     0,   h19_state, empty_init, "Heath Company", "Heathkit H-19 w/ Watzman ROM",  MACHINE_SUPPORTS_SAVE )
 // ULTRA ROM - Software Wizardry, Inc., (c) 1983 William G. Parrott, III
 COMP( 1983, ultra19, h19,    0,      h19_ultrah19,    0,   h19_state, empty_init, "Heath Company", "Heathkit H-19 w/ ULTRA ROM",    MACHINE_SUPPORTS_SAVE )
+// GP-19 - Northwest Digital Systems, (c) 1983
+COMP( 1983, gp19,    h19,    0,      h19_gp19,        0,   h19_state, empty_init, "Heath Company", "Heathkit H-19 w/ GP-19",        MACHINE_NOT_WORKING | MACHINE_SUPPORTS_SAVE )

src/mame/heathkit/tlb.cpp

@@ -12,15 +12,19 @@
     mask-programmed keyboard controller. The output of this passes
     through a rom.
 
-    Input can also come from the serial port (a 8250).
+    Input can also come from the serial port.
-    Either device will signal an interrupt to the CPU when a key
-    is pressed/data is received.
 
   TODO:
     - determine why ULTRA ROM's self-diag (ESC |) fails for the ROM and
       scratchpad memory
     - INS8250 needs to implement "Set Break" (LCR, bit 6) before Break key
       will function as expected.
+    - 49/50 row mode does not work when DOT clocks are programmed as documented
+      in the manual. It does work when DOT clock is fixed at the 20.282 MHz
+      rate.
+    - In 49/50 row mode, character descenders are cut off.
+    - fix GP-19 graphics mode only showing the top half of the image (on the
+      visible screen).
 
 ****************************************************************************/
 /***************************************************************************
@@ -56,12 +60,19 @@
 
 #include "tlb.h"
 
+#include <algorithm>
+
 // Clocks
 static constexpr XTAL MASTER_CLOCK = XTAL(12'288'000);
 
-// Standard H19 used a 2.048 MHz clock
+// DOT clocks
+static constexpr XTAL BASE_DOT_CLOCK = MASTER_CLOCK;
+static constexpr XTAL GP19_DOT_CLOCK_1 = XTAL(20'282'000);   // 132 columns
+static constexpr XTAL GP19_DOT_CLOCK_2 = XTAL(12'292'000);   // 80 columns
+static constexpr XTAL GP19_DOT_CLOCK_3 = XTAL(10'644'000);   // Graphics mode
+
+// Standard H19 used a 2.048 MHz clock for Z80
 static constexpr XTAL H19_CLOCK = MASTER_CLOCK / 6;
-static constexpr XTAL MC6845_CLOCK = MASTER_CLOCK / 8;
 static constexpr XTAL INS8250_CLOCK = MASTER_CLOCK / 4;
 
 // Beep Frequency is 1 KHz
@@ -75,6 +86,7 @@ DEFINE_DEVICE_TYPE(HEATH_TLB, heath_tlb_device, "heath_tlb", "Heath Terminal Log
 DEFINE_DEVICE_TYPE(HEATH_SUPER19, heath_super19_tlb_device, "heath_super19_tlb", "Heath Terminal Logic Board w/Super19 ROM");
 DEFINE_DEVICE_TYPE(HEATH_WATZ, heath_watz_tlb_device, "heath_watz_tlb", "Heath Terminal Logic Board w/Watzman ROM");
 DEFINE_DEVICE_TYPE(HEATH_ULTRA, heath_ultra_tlb_device, "heath_ultra_tlb", "Heath Terminal Logic Board w/Ultra ROM");
+DEFINE_DEVICE_TYPE(HEATH_GP19, heath_gp19_tlb_device, "heath_gp19_tlb", "Heath Terminal Logic Board plus Northwest Digital Systems GP-19")
 
 heath_tlb_device::heath_tlb_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
 	heath_tlb_device(mconfig, HEATH_TLB, tag, owner, clock)
@@ -84,14 +96,15 @@ heath_tlb_device::heath_tlb_device(const machine_config &mconfig, const char *ta
 heath_tlb_device::heath_tlb_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
 	device_t(mconfig, type, tag, owner, clock),
 	m_maincpu(*this, "maincpu"),
-	m_write_sd(*this),
+	m_screen(*this, "screen"),
-	m_reset(*this),
 	m_palette(*this, "palette"),
 	m_crtc(*this, "crtc"),
-	m_ace(*this, "ins8250"),
-	m_beep(*this, "beeper"),
 	m_p_videoram(*this, "videoram"),
 	m_p_chargen(*this, "chargen"),
+	m_write_sd(*this),
+	m_reset(*this),
+	m_ace(*this, "ins8250"),
+	m_beep(*this, "beeper"),
 	m_mm5740(*this, "mm5740"),
 	m_kbdrom(*this, "keyboard"),
 	m_kbspecial(*this, "MODIFIERS"),
@@ -227,7 +240,7 @@ void heath_tlb_device::bell_w(uint8_t data)
 ****************************************************************************/
 uint16_t heath_tlb_device::translate_mm5740_b(uint16_t b)
 {
-	return ((b & 0x100) >> 2) | ((b & 0x0c0) << 1) | (b & 0x03f);
+	return bitswap<9>(b, 7, 6, 8, 5, 4, 3, 2, 1, 0);
 }
 
 uint8_t heath_tlb_device::kbd_key_r()
@@ -262,17 +275,17 @@ uint8_t heath_tlb_device::kbd_flags_r()
 
 int heath_tlb_device::mm5740_shift_r()
 {
-	return ((m_kbspecial->read() & 0x120) != 0x120) ? ASSERT_LINE : CLEAR_LINE;
+	return ((m_kbspecial->read() & 0x120) != 0x120) ? 1 : 0;
 }
 
 int heath_tlb_device::mm5740_control_r()
 {
-	return (m_kbspecial->read() & KB_STATUS_CONTROL_KEY_MASK) ? CLEAR_LINE : ASSERT_LINE;
+	return (m_kbspecial->read() & KB_STATUS_CONTROL_KEY_MASK) ? 0 : 1;
 }
 
 void heath_tlb_device::mm5740_data_ready_w(int state)
 {
-	if (state == ASSERT_LINE)
+	if (state)
 	{
 		uint8_t *decode = m_kbdrom->base();
 
@@ -285,7 +298,7 @@ void heath_tlb_device::mm5740_data_ready_w(int state)
 
 void heath_tlb_device::serial_irq_w(int state)
 {
-	m_serial_irq_raised = state != CLEAR_LINE;
+	m_serial_irq_raised = bool(state);
 	set_irq_line();
 }
 
@@ -301,7 +314,7 @@ void heath_tlb_device::check_for_reset()
 	if (m_reset_key && m_right_shift)
 	{
 		m_reset_pending = true;
-		m_reset(ASSERT_LINE);
+		m_reset(1);
 		m_maincpu->set_input_line(INPUT_LINE_RESET, ASSERT_LINE);
 	}
 	else if (m_reset_pending)
@@ -309,7 +322,7 @@ void heath_tlb_device::check_for_reset()
 		m_reset_pending = false;
 		reset();
 		m_maincpu->set_input_line(INPUT_LINE_RESET, CLEAR_LINE);
-		m_reset(CLEAR_LINE);
+		m_reset(0);
 	}
 }
 
@@ -330,7 +343,7 @@ void heath_tlb_device::right_shift_w(int state)
 void heath_tlb_device::repeat_key_w(int state)
 {
 	// when repeat key pressed, set duty cycle to 0.5, else 0.
-	m_repeat_clock->set_duty_cycle(state == CLEAR_LINE ? 0.5 : 0);
+	m_repeat_clock->set_duty_cycle(state == 0 ? 0.5 : 0);
 }
 
 void heath_tlb_device::break_key_w(int state)
@@ -363,31 +376,14 @@ MC6845_UPDATE_ROW(heath_tlb_device::crtc_update_row)
 			uint8_t const gfx = m_p_chargen[(chr<<4) | ra] ^ inv;
 
 			// Display a scanline of a character (8 pixels)
-			*p++ = palette[BIT(gfx, 7)];
+			for (int b = 0; 8 > b; ++b)
-			*p++ = palette[BIT(gfx, 6)];
+				*p++ = palette[BIT(gfx, 7 - b)];
-			*p++ = palette[BIT(gfx, 5)];
-			*p++ = palette[BIT(gfx, 4)];
-			*p++ = palette[BIT(gfx, 3)];
-			*p++ = palette[BIT(gfx, 2)];
-			*p++ = palette[BIT(gfx, 1)];
-			*p++ = palette[BIT(gfx, 0)];
 		}
 	}
 	else
 	{
 		const rgb_t color = palette[0];
-
+		std::fill_n(p, x_count * 8, color);
-		for (uint16_t x = 0; x < x_count; x++)
-		{
-			*p++ = color; // bit 7
-			*p++ = color; // bit 6
-			*p++ = color; // bit 5
-			*p++ = color; // bit 4
-			*p++ = color; // bit 3
-			*p++ = color; // bit 2
-			*p++ = color; // bit 1
-			*p++ = color; // bit 0
-		}
 	}
 }
 
@@ -709,6 +705,41 @@ static INPUT_PORTS_START( watz19 )
 
 INPUT_PORTS_END
 
+static INPUT_PORTS_START( gp19 )
+	PORT_INCLUDE( tlb )
+
+	PORT_MODIFY("SW402")
+	PORT_DIPNAME( 0x80, 0x00, "Automatic Holdscreen")    PORT_DIPLOCATION("SW402:8")
+	PORT_DIPSETTING(    0x00, "Disabled (VT100 mode)")
+	PORT_DIPSETTING(    0x80, "Enabled (Z19 mode)")
+
+	PORT_START("SW1")
+	PORT_DIPNAME( 0x03, 0x01, "Trailing Characters for Tektronix Message")   PORT_DIPLOCATION("SW1:1,2")
+	PORT_DIPSETTING(    0x00, "None")
+	PORT_DIPSETTING(    0x01, "CR")
+	PORT_DIPSETTING(    0x02, "None")
+	PORT_DIPSETTING(    0x03, "CR,EOT")
+	PORT_DIPNAME( 0x04, 0x01, "Shift Key")                                   PORT_DIPLOCATION("SW1:3")
+	PORT_DIPSETTING(    0x00, "Normal")
+	PORT_DIPSETTING(    0x04, "Shift key inverts CAPS LOCK")
+	PORT_DIPNAME( 0x08, 0x00, "Terminal Transmission Rate")                  PORT_DIPLOCATION("SW1:4")
+	PORT_DIPSETTING(    0x00, "Only limited by baud rate")
+	PORT_DIPSETTING(    0x08, "One character per 16.7 msec")
+	PORT_DIPNAME( 0x10, 0x10, "Character Set")                               PORT_DIPLOCATION("SW1:5")
+	PORT_DIPSETTING(    0x00, "VT100")
+	PORT_DIPSETTING(    0x10, "Zenith")
+	PORT_DIPNAME( 0x20, 0x00, "ANSI Mode")                                   PORT_DIPLOCATION("SW1:6")
+	PORT_DIPSETTING(    0x00, "Zenith ANSI")
+	PORT_DIPSETTING(    0x20, "EDT compatible")
+	PORT_DIPNAME( 0x40, 0x00, "Tektronix Character Wrap")                    PORT_DIPLOCATION("SW1:7")
+	PORT_DIPSETTING(    0x00, "Column 74")
+	PORT_DIPSETTING(    0x40, "Column 73")
+	PORT_DIPNAME( 0x80, 0x00, "Blank Screen")                                PORT_DIPLOCATION("SW1:8")
+	PORT_DIPSETTING(    0x00, "After 10 mins")
+	PORT_DIPSETTING(    0x80, "Never")
+
+INPUT_PORTS_END
+
 
 ROM_START( h19 )
 	ROM_REGION( 0x2000, "maincpu", ROMREGION_ERASEFF )
@@ -770,6 +801,23 @@ ROM_START( ultra19 )
 	ROM_LOAD( "2716_h19_ultra_keyboard.bin", 0x0000, 0x0800, CRC(76130c92) SHA1(ca39c602af48505139d2750a084b5f8f0e662ff7))
 ROM_END
 
+ROM_START( gp19 )
+	// GP-19 ROMs
+	ROM_REGION( 0x3000, "maincpu", ROMREGION_ERASEFF )
+	ROM_LOAD( "gp19_rom_1_ver_1_1.bin", 0x0000, 0x1000, CRC(7cbe8e0d) SHA1(977df895b067fa4e4646b4518cffb08d4e6bb6e0))
+	ROM_LOAD( "gp19_rom_2_ver_1_1.bin", 0x1000, 0x1000, CRC(a85e3bc4) SHA1(f64e851c5d3ef98a9a48e0fc482baa576773ff43))
+	ROM_LOAD( "gp19_rom_3_ver_1_1.bin", 0x2000, 0x1000, CRC(878f577c) SHA1(0756435914dcfb981de4e40d5f81af3e0f5bb1c5))
+
+	ROM_REGION( 0x1000, "chargen", 0 )
+	// GP-19 font
+	ROM_LOAD( "gp19_char_gen_cg_1.bin", 0x0000, 0x1000, CRC(49ec9242) SHA1(770a8c7b5b15bcfe465fd84326d0ae3dcaa85311))
+
+	ROM_REGION( 0x1000, "keyboard", 0 )
+	// Original dump
+	ROM_LOAD( "2716_444-37_h19keyb.bin", 0x0000, 0x0800, CRC(5c3e6972) SHA1(df49ce64ae48652346a91648c58178a34fb37d3c))
+ROM_END
+
+
 
 ioport_constructor heath_tlb_device::device_input_ports() const
 {
@@ -800,14 +848,16 @@ void heath_tlb_device::device_add_mconfig(machine_config &config)
 
 	// video hardware
 	// TODO: make configurable, Heath offered 2 different CRTs - White, Green
-	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER, rgb_t::green()));
+	SCREEN(config, m_screen, SCREEN_TYPE_RASTER, rgb_t::green());
-	screen.set_raw(MC6845_CLOCK * 45 / 2, 900, 260, 0, 640, 0, 250);
+	// based on the H19 ROM code for 60 Hz
-	screen.set_screen_update("crtc", FUNC(mc6845_device::screen_update));
+	m_screen->set_raw(BASE_DOT_CLOCK, 768, 32, 672, 270, 0, 250);
+	m_screen->set_screen_update("crtc", FUNC(mc6845_device::screen_update));
 
 	GFXDECODE(config, "gfxdecode", m_palette, gfx_h19);
 	PALETTE(config, "palette", palette_device::MONOCHROME);
 
-	MC6845(config, m_crtc, MC6845_CLOCK);
+	// MC 6845 uses a character clock, divide the DOT clock by 8.
+	MC6845(config, m_crtc, BASE_DOT_CLOCK / 8);
 	m_crtc->set_screen("screen");
 	m_crtc->set_show_border_area(true);
 	m_crtc->set_char_width(8);
@@ -839,6 +889,7 @@ void heath_tlb_device::device_add_mconfig(machine_config &config)
 	SPEAKER(config, "mono").front_center();
 	BEEP(config, m_beep, H19_BEEP_FRQ).add_route(ALL_OUTPUTS, "mono", 0.05);
 
+	// clock for repeat key
 	CLOCK(config, m_repeat_clock, 40);
 	m_repeat_clock->set_duty_cycle(0);
 	m_repeat_clock->signal_handler().set(m_mm5740, FUNC(mm5740_device::repeat_line_w));
@@ -906,3 +957,167 @@ ioport_constructor heath_ultra_tlb_device::device_input_ports() const
 {
 	return INPUT_PORTS_NAME(ultra19);
 }
+
+/**
+ * Northwest Digital Systems GP-19 add-in board
+ */
+heath_gp19_tlb_device::heath_gp19_tlb_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	heath_tlb_device(mconfig, HEATH_GP19, tag, owner, clock)
+{
+}
+
+void heath_gp19_tlb_device::device_add_mconfig(machine_config &config)
+{
+	heath_tlb_device::device_add_mconfig(config);
+
+	m_maincpu->set_addrmap(AS_PROGRAM, &heath_gp19_tlb_device::mem_map);
+	m_maincpu->set_addrmap(AS_IO, &heath_gp19_tlb_device::io_map);
+
+	m_crtc->set_update_row_callback(FUNC(heath_gp19_tlb_device::crtc_update_row));
+	m_crtc->set_clock(GP19_DOT_CLOCK_2 / 8);
+
+	m_screen->set_raw(GP19_DOT_CLOCK_2, 776, 32, 672, 264, 10, 250);
+
+}
+
+void heath_gp19_tlb_device::device_start()
+{
+	heath_tlb_device::device_start();
+
+	save_item(NAME(m_char_gen_a11));
+	save_item(NAME(m_graphic_mode));
+	save_item(NAME(m_col_132));
+	save_item(NAME(m_reverse_video));
+
+	m_char_gen_a11 = false;
+	m_graphic_mode = false;
+	m_col_132 = false;
+	m_reverse_video = false;
+
+}
+
+void heath_gp19_tlb_device::mem_map(address_map &map)
+{
+	// ROMs 1, 2, 3
+	map(0x0000, 0x02fff).rom();
+
+	// Optional external board - Program ROM 4, external I/O
+	// map(0x3000, 0x03fff).rom();
+
+	map(0x4000, 0x40ff).mirror(0x3f00).ram();
+	map(0x6000, 0x67ff).mirror(0x1800).ram();
+	map(0x8000, 0xbfff).mirror(0x4000).ram().share(m_p_videoram);
+}
+
+
+void heath_gp19_tlb_device::io_map(address_map &map)
+{
+	heath_tlb_device::io_map(map);
+
+	// Latch U5
+	map(0x68, 0x68).mirror(0x07).w(FUNC(heath_gp19_tlb_device::latch_u5_w));
+
+	// Switch on GP-19 board
+	map(0x70, 0x70).mirror(0x07).portr("SW1");
+
+	// Optional Auxiliary I/O connector
+	// map(0x78, 0x78).mirror(0x07);
+}
+
+/**
+ * U5 Latch
+ *
+ *  Q0 Graph/character H
+ *  Q1 132/80 columns H
+ *  Q2 Reverse Screen H
+ *  Q3 Alt Character L
+ *  Q4-Q7 LED indicators (debug LEDs on circuit board)
+ */
+void heath_gp19_tlb_device::latch_u5_w(uint8_t data)
+{
+	m_graphic_mode = bool(BIT(data, 0));
+	m_col_132 = bool(BIT(data, 1));
+	m_reverse_video = bool(BIT(data, 2));
+	m_char_gen_a11 = bool(BIT(data, 3));
+
+	// TODO handle LED indicators
+
+	if (m_graphic_mode)
+	{
+		m_crtc->set_clock(GP19_DOT_CLOCK_3 / 8);
+		m_screen->set_raw(GP19_DOT_CLOCK_3, 672, 50, 560, 264, 0, 250);
+	}
+	else if (m_col_132)
+	{
+		m_crtc->set_clock(GP19_DOT_CLOCK_1 / 8);
+		m_screen->set_raw(GP19_DOT_CLOCK_1, 1280, 1088, 33, 264, 10, 250);
+	}
+	else
+	{
+		m_crtc->set_clock(GP19_DOT_CLOCK_2 / 8);
+		m_screen->set_raw(GP19_DOT_CLOCK_2, 776, 32, 672, 264, 10, 250);
+	}
+}
+
+
+MC6845_UPDATE_ROW(heath_gp19_tlb_device::crtc_update_row)
+{
+	rgb_t const *const palette = m_palette->palette()->entry_list_raw();
+	uint32_t *p = &bitmap.pix(y);
+
+	if (de)
+	{
+		uint8_t screen_inv = m_reverse_video ? 0xff : 0x00;
+
+		if (m_graphic_mode)
+		{
+			for (uint16_t x = 0; x < x_count; x++)
+			{
+				uint8_t const gfx = m_p_videoram[(ma + x) & 0x3fff] ^ screen_inv;
+				for (int b = 0; 8 > b; ++b)
+					*p++ = palette[BIT(gfx, b)];
+			}
+		}
+		else
+		{
+			for (uint16_t x = 0; x < x_count; x++)
+			{
+				uint8_t inv = (x == cursor_x) ? 0xff : 0;
+
+				uint8_t chr = m_p_videoram[(ma + x) & 0x3fff];
+
+				if (chr & 0x80)
+				{
+					inv ^= 0xff;
+					chr &= 0x7f;
+				}
+
+				inv ^= screen_inv;
+
+				// select proper character set
+				uint16_t base = m_char_gen_a11 ? 0x800 : 0x0;
+
+				uint8_t const gfx = m_p_chargen[base | (chr << 4) | ra] ^ inv;
+
+				// Display a scanline of a character (8 pixels)
+				for (int b = 0; 8 > b; ++b)
+					*p++ = palette[BIT(gfx, 7 - b)];
+			}
+		}
+	}
+	else
+	{
+		const rgb_t color = palette[0];
+		std::fill_n(p, x_count * 8, color);
+	}
+}
+
+const tiny_rom_entry *heath_gp19_tlb_device::device_rom_region() const
+{
+	return ROM_NAME(gp19);
+}
+
+ioport_constructor heath_gp19_tlb_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME(gp19);
+}

src/mame/heathkit/tlb.h

@@ -21,6 +21,8 @@
 #include "screen.h"
 #include "speaker.h"
 
+
+// Standard Heath Terminal logic board
 class heath_tlb_device : public device_t
 {
 public:
@@ -50,7 +52,14 @@ protected:
 	void mem_map(address_map &map);
 	void io_map(address_map &map);
 
-	required_device<cpu_device> m_maincpu;
+	virtual MC6845_UPDATE_ROW(crtc_update_row);
+
+	required_device<cpu_device>     m_maincpu;
+	required_device<screen_device>  m_screen;
+	required_device<palette_device> m_palette;
+	required_device<mc6845_device>  m_crtc;
+	required_shared_ptr<uint8_t>    m_p_videoram;
+	required_region_ptr<uint8_t>    m_p_chargen;
 
 private:
 	void set_irq_line();
@@ -70,8 +79,6 @@ private:
 	int mm5740_control_r();
 	void mm5740_data_ready_w(int state);
 
-	MC6845_UPDATE_ROW(crtc_update_row);
-
 	TIMER_CALLBACK_MEMBER(key_click_off);
 	TIMER_CALLBACK_MEMBER(bell_off);
 
@@ -81,12 +88,8 @@ private:
 	devcb_write_line m_write_sd;
 	devcb_write_line m_reset;
 
-	required_device<palette_device> m_palette;
-	required_device<mc6845_device>  m_crtc;
 	required_device<ins8250_device> m_ace;
 	required_device<beep_device>    m_beep;
-	required_shared_ptr<uint8_t>    m_p_videoram;
-	required_region_ptr<uint8_t>    m_p_chargen;
 	required_device<mm5740_device>  m_mm5740;
 	required_memory_region          m_kbdrom;
 	required_ioport                 m_kbspecial;
@@ -104,6 +107,7 @@ private:
 	bool     m_break_key_irq_raised;
 };
 
+// Heath TLB with Super19 ROM
 class heath_super19_tlb_device : public heath_tlb_device
 {
 public:
@@ -114,6 +118,7 @@ protected:
 	virtual ioport_constructor device_input_ports() const override;
 };
 
+// Heath TLB with Watzman (HUG) ROM
 class heath_watz_tlb_device : public heath_tlb_device
 {
 public:
@@ -124,6 +129,7 @@ protected:
 	virtual ioport_constructor device_input_ports() const override;
 };
 
+// Heath TLB with Ultra ROM
 class heath_ultra_tlb_device : public heath_tlb_device
 {
 public:
@@ -137,7 +143,34 @@ protected:
 	void mem_map(address_map &map);
 };
 
+// Heath TLB plus Northwest Digital Systems GP-19
+class heath_gp19_tlb_device : public heath_tlb_device
+{
+public:
+	heath_gp19_tlb_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
+
+protected:
+	virtual const tiny_rom_entry *device_rom_region() const override;
+	virtual ioport_constructor device_input_ports() const override;
+
+	virtual void device_start() override;
+	virtual void device_add_mconfig(machine_config &config) override;
+
+	void mem_map(address_map &map);
+	void io_map(address_map &map);
+
+	void latch_u5_w(uint8_t data);
+
+	virtual MC6845_UPDATE_ROW(crtc_update_row) override;
+
+	bool m_char_gen_a11;
+	bool m_graphic_mode;
+	bool m_col_132;
+	bool m_reverse_video;
+};
+
 DECLARE_DEVICE_TYPE(HEATH_TLB, heath_tlb_device)
+DECLARE_DEVICE_TYPE(HEATH_GP19, heath_gp19_tlb_device)
 DECLARE_DEVICE_TYPE(HEATH_SUPER19, heath_super19_tlb_device)
 DECLARE_DEVICE_TYPE(HEATH_WATZ, heath_watz_tlb_device)
 DECLARE_DEVICE_TYPE(HEATH_ULTRA, heath_ultra_tlb_device)

src/mame/mame.lst

@@ -19171,9 +19171,10 @@ h8                              //
 
 @source:heathkit/h19.cpp
 h19                             // Heath H19 (Zenith Z-19)
+gp19                            // H19 with Northwest Digital Systems GP-19
 super19                         // Super19 replacement ROMS for H19
-watz19                          // Watzman replacement ROMS for H19
 ultra19                         // ULTRA ROM replacement ROMS for H19
+watz19                          // Watzman replacement ROMS for H19
 
 @source:heathkit/h89.cpp
 h89                             //