diff --git a/scripts/src/bus.lua b/scripts/src/bus.lua
index 2c708f35b4d..14e6b6187f6 100644
--- a/scripts/src/bus.lua
+++ b/scripts/src/bus.lua
@@ -2198,6 +2198,23 @@ if (BUSES["WANGPC"]~=null) then
 end
 
 
+---------------------------------------------------
+--
+--@src/devices/bus/z29_kbd/keyboard.h,BUSES["Z29_KBD"] = true
+---------------------------------------------------
+
+if (BUSES["Z29_KBD"]~=null) then
+	files {
+		MAME_DIR .. "src/devices/bus/z29_kbd/keyboard.cpp",
+		MAME_DIR .. "src/devices/bus/z29_kbd/keyboard.h",
+		MAME_DIR .. "src/devices/bus/z29_kbd/he191_3425.cpp",
+		MAME_DIR .. "src/devices/bus/z29_kbd/he191_3425.h",
+		MAME_DIR .. "src/devices/bus/z29_kbd/md_kbd.cpp",
+		MAME_DIR .. "src/devices/bus/z29_kbd/md_kbd.h",
+	}
+end
+
+
 ---------------------------------------------------
 --
 --@src/devices/bus/z88/z88.h,BUSES["Z88"] = true
diff --git a/scripts/target/mame/mess.lua b/scripts/target/mame/mess.lua
index 396ed5572b6..db3a00a065b 100644
--- a/scripts/target/mame/mess.lua
+++ b/scripts/target/mame/mess.lua
@@ -918,6 +918,7 @@ BUSES["VTECH_MEMEXP"] = true
 BUSES["WANGPC"] = true
 BUSES["WSWAN"] = true
 BUSES["X68K"] = true
+BUSES["Z29_KBD"] = true
 BUSES["Z88"] = true
 BUSES["ZORRO"] = true
 
@@ -4179,6 +4180,7 @@ createMESSProjects(_target, _subtarget, "zenith")
 files {
 	MAME_DIR .. "src/mame/drivers/mdt60.cpp",
 	MAME_DIR .. "src/mame/drivers/z100.cpp",
+	MAME_DIR .. "src/mame/drivers/z22.cpp",
 	MAME_DIR .. "src/mame/drivers/z29.cpp",
 }
 
diff --git a/src/devices/bus/z29_kbd/he191_3425.cpp b/src/devices/bus/z29_kbd/he191_3425.cpp
new file mode 100644
index 00000000000..69ea07f76d1
--- /dev/null
+++ b/src/devices/bus/z29_kbd/he191_3425.cpp
@@ -0,0 +1,240 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+/***************************************************************************
+
+    Heath HE 191-3425 keyboard
+
+    This 91-key detached keyboard is standard issue for the H-29 (Z-29)
+    terminal. It is also specified for the MDT 60 in its schematics.
+
+    Since the 8021 MCU is not dumped, emulation is more or less a stub.
+
+***************************************************************************/
+
+#include "emu.h"
+#include "he191_3425.h"
+
+#include "cpu/mcs48/mcs48.h"
+#include "machine/rescap.h"
+#include "speaker.h"
+
+
+DEFINE_DEVICE_TYPE(HE191_3425, he191_3425_device, "he191_3425", "Heath HE 191-3425 Keyboard")
+
+he191_3425_device::he191_3425_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+	: device_t(mconfig, HE191_3425, tag, owner, clock)
+	, device_z29_keyboard_interface(mconfig, *this)
+	, m_mcu(*this, "mcu")
+	, m_buzzer(*this, "buzzer")
+	, m_matrix(*this, {"B1", "B2", "B3", "B4", "B5", "B6", "B7", "B8", "B9", "B11", "B13", "B14"})
+	, m_modifiers(*this, "MODIFIERS")
+	, m_leds(*this, "led%u", 1U)
+	, m_select(0)
+	, m_recv_data(true)
+{
+}
+
+void he191_3425_device::device_resolve_objects()
+{
+	m_leds.resolve();
+}
+
+void he191_3425_device::device_start()
+{
+	m_leds[0] = 1; // L1: Power
+
+	save_item(NAME(m_select));
+	save_item(NAME(m_recv_data));
+}
+
+void he191_3425_device::receive_data(bool state)
+{
+	machine().scheduler().synchronize(timer_expired_delegate(FUNC(he191_3425_device::receive_data_synced), this), state);
+}
+
+TIMER_CALLBACK_MEMBER(he191_3425_device::receive_data_synced)
+{
+	m_recv_data = param;
+}
+
+u8 he191_3425_device::mcu_pa_r()
+{
+	return m_select < 12 ? m_matrix[m_select]->read() : 0xff;
+}
+
+void he191_3425_device::mcu_pb_w(u8 data)
+{
+	transmit_data(!BIT(data, 3));
+	m_leds[1] = !BIT(data, 4); // L2: Keyboard Lock
+	m_leds[2] = !BIT(data, 5); // L3: Off/Line
+	m_leds[3] = !BIT(data, 6); // L4: Caps Lock
+	m_buzzer->set_state(BIT(data, 7));
+}
+
+void he191_3425_device::mcu_pc_w(u8 data)
+{
+	m_select = data & 0xf;
+}
+
+READ_LINE_MEMBER(he191_3425_device::mcu_t1_r)
+{
+	return m_recv_data;
+}
+
+WRITE_LINE_MEMBER(he191_3425_device::shift_reset)
+{
+	m_mcu->set_input_line(INPUT_LINE_RESET, (m_modifiers->read() & 0x06) != 0x00 ? CLEAR_LINE : ASSERT_LINE);
+	reset_from_keyboard((m_modifiers->read() & 0x06) != 0x00);
+}
+
+
+static INPUT_PORTS_START(he191_3425)
+	PORT_START("B1")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(ENTER_PAD)) PORT_CODE(KEYCODE_ENTER_PAD)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(DEL_PAD)) PORT_CODE(KEYCODE_DEL_PAD)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(0_PAD)) PORT_CODE(KEYCODE_0_PAD)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('`') PORT_CHAR('~') PORT_CODE(KEYCODE_BACKSLASH)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('0') PORT_CHAR(')') PORT_CODE(KEYCODE_0)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('o') PORT_CHAR('O') PORT_CODE(KEYCODE_O)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(';') PORT_CHAR(':') PORT_CODE(KEYCODE_COLON)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('/') PORT_CHAR('?') PORT_CODE(KEYCODE_SLASH)
+
+	PORT_START("B2")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Keypad 3  DL") PORT_CHAR(UCHAR_MAMEKEY(3_PAD)) PORT_CODE(KEYCODE_3_PAD)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(2_PAD)) PORT_CODE(KEYCODE_2_PAD)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Keypad 1  IL") PORT_CHAR(UCHAR_MAMEKEY(1_PAD)) PORT_CODE(KEYCODE_1_PAD)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F9)) PORT_CODE(KEYCODE_F9)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('9') PORT_CHAR('(') PORT_CODE(KEYCODE_9)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('i') PORT_CHAR('I') PORT_CODE(KEYCODE_I)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('l') PORT_CHAR('L') PORT_CODE(KEYCODE_L)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('.') PORT_CHAR('>') PORT_CODE(KEYCODE_STOP)
+
+	PORT_START("B3")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(6_PAD)) PORT_CODE(KEYCODE_6_PAD)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(5_PAD)) PORT_CODE(KEYCODE_5_PAD)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(4_PAD)) PORT_CODE(KEYCODE_4_PAD)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F8)) PORT_CODE(KEYCODE_F8)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('8') PORT_CHAR('*') PORT_CODE(KEYCODE_8)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('u') PORT_CHAR('U') PORT_CODE(KEYCODE_U)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('k') PORT_CHAR('K') PORT_CODE(KEYCODE_K)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(',') PORT_CHAR('<') PORT_CODE(KEYCODE_COMMA)
+
+	PORT_START("B4")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Keypad 9  DC") PORT_CHAR(UCHAR_MAMEKEY(9_PAD)) PORT_CODE(KEYCODE_9_PAD)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(8_PAD)) PORT_CODE(KEYCODE_8_PAD)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Keypad 7  IC") PORT_CHAR(UCHAR_MAMEKEY(7_PAD)) PORT_CODE(KEYCODE_7_PAD)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F7)) PORT_CODE(KEYCODE_F7)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('7') PORT_CHAR('&') PORT_CODE(KEYCODE_7)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('y') PORT_CHAR('Y') PORT_CODE(KEYCODE_Y)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('j') PORT_CHAR('J') PORT_CODE(KEYCODE_J)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('m') PORT_CHAR('M') PORT_CODE(KEYCODE_M)
+
+	PORT_START("B5")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Help") PORT_CODE(KEYCODE_F10)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Line Feed") PORT_CHAR(0x0a) PORT_CODE(KEYCODE_RALT)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Space Bar") PORT_CHAR(' ') PORT_CODE(KEYCODE_SPACE)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F6)) PORT_CODE(KEYCODE_F6)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('6') PORT_CHAR('^') PORT_CODE(KEYCODE_6)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('t') PORT_CHAR('T') PORT_CODE(KEYCODE_T)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('h') PORT_CHAR('H') PORT_CODE(KEYCODE_H)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('n') PORT_CHAR('N') PORT_CODE(KEYCODE_N)
+
+	PORT_START("B6")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('\\') PORT_CHAR('|') PORT_CODE(KEYCODE_RCONTROL) // to right of Return key
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Return") PORT_CHAR(0x0d) PORT_CODE(KEYCODE_ENTER)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('\'') PORT_CHAR('"') PORT_CODE(KEYCODE_QUOTE)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F5)) PORT_CODE(KEYCODE_F5)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('5') PORT_CHAR('%') PORT_CODE(KEYCODE_5)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('r') PORT_CHAR('R') PORT_CODE(KEYCODE_R)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('g') PORT_CHAR('G') PORT_CODE(KEYCODE_G)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('b') PORT_CHAR('B') PORT_CODE(KEYCODE_B)
+
+	PORT_START("B7")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(']') PORT_CHAR('}') PORT_CODE(KEYCODE_CLOSEBRACE)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('[') PORT_CHAR('{') PORT_CODE(KEYCODE_OPENBRACE)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('p') PORT_CHAR('P') PORT_CODE(KEYCODE_P)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F4)) PORT_CODE(KEYCODE_F4)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('4') PORT_CHAR('$') PORT_CODE(KEYCODE_4)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('e') PORT_CHAR('E') PORT_CODE(KEYCODE_E)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('f') PORT_CHAR('F') PORT_CODE(KEYCODE_F)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('v') PORT_CHAR('V') PORT_CODE(KEYCODE_V)
+
+	PORT_START("B8")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Delete") PORT_CHAR(UCHAR_MAMEKEY(DEL)) PORT_CODE(KEYCODE_DEL) // to right of `/~ key
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(HOME)) PORT_CODE(KEYCODE_F11)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(DOWN)) PORT_CODE(KEYCODE_DOWN) // between +/= and Back Space keys
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F3)) PORT_CODE(KEYCODE_F3)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('3') PORT_CHAR('#') PORT_CODE(KEYCODE_3)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('w') PORT_CHAR('W') PORT_CODE(KEYCODE_W)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('d') PORT_CHAR('D') PORT_CODE(KEYCODE_D)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('c') PORT_CHAR('C') PORT_CODE(KEYCODE_C)
+
+	PORT_START("B9")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Back Space") PORT_CHAR(0x08) PORT_CODE(KEYCODE_BACKSPACE)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('=') PORT_CHAR('+') PORT_CODE(KEYCODE_EQUALS)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('-') PORT_CHAR('_') PORT_CODE(KEYCODE_MINUS)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F2)) PORT_CODE(KEYCODE_F2)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('2') PORT_CHAR('@') PORT_CODE(KEYCODE_2)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('q') PORT_CHAR('Q') PORT_CODE(KEYCODE_Q)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('s') PORT_CHAR('S') PORT_CODE(KEYCODE_S)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('x') PORT_CHAR('X') PORT_CODE(KEYCODE_X)
+
+	PORT_START("B11")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(RIGHT)) PORT_CODE(KEYCODE_RIGHT)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(UP)) PORT_CODE(KEYCODE_UP)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(LEFT)) PORT_CODE(KEYCODE_LEFT) // to right of Home key
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F1)) PORT_CODE(KEYCODE_F1)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('1') PORT_CHAR('!') PORT_CODE(KEYCODE_1)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Tab") PORT_CHAR('\t') PORT_CODE(KEYCODE_TAB)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('a') PORT_CHAR('A') PORT_CODE(KEYCODE_A)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('z') PORT_CHAR('Z') PORT_CODE(KEYCODE_Z)
+
+	PORT_START("B13")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(COMMA_PAD)) PORT_CODE(KEYCODE_PLUS_PAD)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(MINUS_PAD)) PORT_CODE(KEYCODE_MINUS_PAD)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("No Scroll") PORT_CODE(KEYCODE_LALT)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Set Up") PORT_CODE(KEYCODE_ESC)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Esc") PORT_CHAR(0x1b) PORT_CODE(KEYCODE_TILDE)
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Erase") PORT_CODE(KEYCODE_F12)
+
+	PORT_START("B14")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(CAPSLOCK)) PORT_CODE(KEYCODE_CAPSLOCK)
+	PORT_BIT(0xfe, IP_ACTIVE_LOW, IPT_UNUSED)
+
+	PORT_START("MODIFIERS")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Ctrl") PORT_CHAR(UCHAR_SHIFT_2) PORT_CODE(KEYCODE_LCONTROL)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Shift") PORT_CHAR(UCHAR_SHIFT_1) PORT_CODE(KEYCODE_LSHIFT) PORT_CODE(KEYCODE_RSHIFT) PORT_WRITE_LINE_MEMBER(he191_3425_device, shift_reset)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Break  Reset") PORT_CODE(KEYCODE_PAUSE) PORT_WRITE_LINE_MEMBER(he191_3425_device, shift_reset) // to right of Back Space key
+	PORT_BIT(0xf8, IP_ACTIVE_LOW, IPT_UNUSED)
+INPUT_PORTS_END
+
+ioport_constructor he191_3425_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME(he191_3425);
+}
+
+void he191_3425_device::device_add_mconfig(machine_config &config)
+{
+	i8021_device &mcu(I8021(config, m_mcu, 3.579545_MHz_XTAL));
+	mcu.bus_in_cb().set(FUNC(he191_3425_device::mcu_pa_r));
+	mcu.p1_in_cb().set_ioport("MODIFIERS");
+	mcu.p1_out_cb().set(FUNC(he191_3425_device::mcu_pb_w));
+	mcu.p2_out_cb().set(FUNC(he191_3425_device::mcu_pc_w));
+	mcu.t1_in_cb().set(FUNC(he191_3425_device::mcu_t1_r));
+
+	SPEAKER(config, "speaker").front_center();
+	BEEP(config, m_buzzer, 1'000'000'000 / PERIOD_OF_555_ASTABLE_NSEC(RES_R(510), RES_R(510), CAP_U(1)));
+	m_buzzer->add_route(ALL_OUTPUTS, "speaker", 1.0);
+}
+
+ROM_START(he191_3425)
+	ROM_REGION(0x400, "mcu", ROMREGION_ERASE00)
+	ROM_LOAD("p8021h-2155_444-100.z1", 0x000, 0x400, NO_DUMP)
+ROM_END
+
+const tiny_rom_entry *he191_3425_device::device_rom_region() const
+{
+	return ROM_NAME(he191_3425);
+}
diff --git a/src/devices/bus/z29_kbd/he191_3425.h b/src/devices/bus/z29_kbd/he191_3425.h
new file mode 100644
index 00000000000..cf0129936fb
--- /dev/null
+++ b/src/devices/bus/z29_kbd/he191_3425.h
@@ -0,0 +1,58 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+
+#ifndef MAME_BUS_Z29_KBD_HE191_3425_H
+#define MAME_BUS_Z29_KBD_HE191_3425_H
+
+#pragma once
+
+#include "bus/z29_kbd/keyboard.h"
+#include "sound/beep.h"
+
+
+class he191_3425_device : public device_t, public device_z29_keyboard_interface
+{
+public:
+	// device type constructor
+	he191_3425_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock);
+
+	// miscellanous handlers
+	DECLARE_WRITE_LINE_MEMBER(shift_reset);
+
+protected:
+	// device-level overrides
+	virtual void device_resolve_objects() override;
+	virtual void device_start() override;
+	virtual ioport_constructor device_input_ports() const override;
+	virtual void device_add_mconfig(machine_config &config) override;
+	virtual const tiny_rom_entry *device_rom_region() const override;
+
+	// device_z29_keyboard_interface overrides
+	virtual void receive_data(bool state) override;
+
+private:
+	// MCU port handlers
+	u8 mcu_pa_r();
+	void mcu_pb_w(u8 data);
+	void mcu_pc_w(u8 data);
+	DECLARE_READ_LINE_MEMBER(mcu_t1_r);
+
+	// misc. helpers
+	TIMER_CALLBACK_MEMBER(receive_data_synced);
+
+	// object finders
+	required_device<cpu_device> m_mcu;
+	required_device<beep_device> m_buzzer;
+	required_ioport_array<12> m_matrix;
+	required_ioport m_modifiers;
+	output_finder<4> m_leds;
+
+	// internal state
+	u8 m_select;
+	bool m_recv_data;
+};
+
+// device type declaration
+DECLARE_DEVICE_TYPE(HE191_3425, he191_3425_device)
+
+#endif // MAME_BUS_Z29_KBD_HE191_3425_H
diff --git a/src/devices/bus/z29_kbd/keyboard.cpp b/src/devices/bus/z29_kbd/keyboard.cpp
new file mode 100644
index 00000000000..637bc8d4389
--- /dev/null
+++ b/src/devices/bus/z29_kbd/keyboard.cpp
@@ -0,0 +1,117 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+/***************************************************************************
+
+    Zenith Z-29 keyboard port
+
+    This supports the custom serial interface for the H-29/Z-29 and other
+    early Heath/Zenith terminals with detachable keyboards. (Keyboards for
+    later Zenith terminals such as the Z-49 use a standard asynchronous
+    serial protocol.)
+
+    All printable characters outside of the numeric keypad use standard
+    ASCII codes, as do Back Space, Line Feed, Return, Esc and Del. The
+    following codes are assigned to other keys:
+
+        80              Up
+        81              Down
+        82              Left
+        83              Right
+        84              Home
+        85              Erase
+        86              Help
+        87              No Scroll
+        88              Set Up
+        89              Break
+        8A              Caps Lock
+        8B              Tab
+        8C              Space Bar
+        8F              (Power On)
+        90              0 (Keypad)
+        91              1 (Keypad)
+        92              2 (Keypad)
+        93              3 (Keypad)
+        94              4 (Keypad)
+        95              5 (Keypad)
+        96              6 (Keypad)
+        97              7 (Keypad)
+        98              8 (Keypad)
+        99              9 (Keypad)
+        9A              . (Keypad)
+        9B              Enter (Keypad)
+        9C              - (Keypad)
+        9D              , (Keypad)
+        9F 80           F1
+        9F 81           F2
+        9F 82           F3
+        9F 83           F4
+        9F 84           F5
+        9F 85           F6
+        9F 86           F7
+        9F 87           F8
+        9F 88           F9
+
+    Bit 6 is set in these codes when pressed with Shift, and bit 5 when
+    pressed with Ctrl.
+
+***************************************************************************/
+
+#include "emu.h"
+#include "keyboard.h"
+
+#include "he191_3425.h"
+#include "md_kbd.h"
+
+//**************************************************************************
+//  Z-29 KEYBOARD PORT DEVICE
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(Z29_KEYBOARD, z29_keyboard_port_device, "z29_kbd", "Z-29 Keyboard Port")
+
+z29_keyboard_port_device::z29_keyboard_port_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+	: device_t(mconfig, Z29_KEYBOARD, tag, owner, clock)
+	, device_single_card_slot_interface<device_z29_keyboard_interface>(mconfig, *this)
+	, m_keyin_callback(*this)
+	, m_reset_callback(*this)
+	, m_kbd(nullptr)
+{
+}
+
+void z29_keyboard_port_device::device_config_complete()
+{
+	m_kbd = get_card_device();
+}
+
+void z29_keyboard_port_device::device_resolve_objects()
+{
+	m_keyin_callback.resolve_safe();
+	m_reset_callback.resolve_safe();
+}
+
+void z29_keyboard_port_device::device_start()
+{
+}
+
+//**************************************************************************
+//  Z-29 KEYBOARD INTERFACE
+//**************************************************************************
+
+device_z29_keyboard_interface::device_z29_keyboard_interface(const machine_config &mconfig, device_t &device)
+	: device_interface(device, "z29kbd")
+	, m_port(device, DEVICE_SELF_OWNER)
+{
+}
+
+device_z29_keyboard_interface::~device_z29_keyboard_interface()
+{
+}
+
+//**************************************************************************
+//  KEYBOARD OPTIONS
+//**************************************************************************
+
+void z29_keyboards(device_slot_interface &slot)
+{
+	slot.option_add("heath", HE191_3425);
+	slot.option_add("md", MD_KEYBOARD);
+}
diff --git a/src/devices/bus/z29_kbd/keyboard.h b/src/devices/bus/z29_kbd/keyboard.h
new file mode 100644
index 00000000000..501d8bbe569
--- /dev/null
+++ b/src/devices/bus/z29_kbd/keyboard.h
@@ -0,0 +1,104 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+/***************************************************************************
+
+    Zenith Z-29 keyboard port
+
+***************************************************************************/
+
+#ifndef MAME_BUS_Z29_KBD_KEYBOARD_H
+#define MAME_BUS_Z29_KBD_KEYBOARD_H
+
+#pragma once
+
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+// forward declaration
+class device_z29_keyboard_interface;
+
+// ======================> z29_keyboard_port_device
+
+class z29_keyboard_port_device : public device_t, public device_single_card_slot_interface<device_z29_keyboard_interface>
+{
+	friend class device_z29_keyboard_interface;
+
+public:
+	// construction/destruction
+	z29_keyboard_port_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock);
+	template <typename T>
+	z29_keyboard_port_device(const machine_config &mconfig, const char *tag, device_t *owner, T &&opts, const char *dflt)
+		: z29_keyboard_port_device(mconfig, tag, owner, 0U)
+	{
+		option_reset();
+		opts(*this);
+		set_default_option(dflt);
+		set_fixed(false);
+	}
+
+	// callback configuration
+	auto keyin_callback() { return m_keyin_callback.bind(); }
+	auto reset_callback() { return m_reset_callback.bind(); }
+
+	// line handler
+	inline DECLARE_WRITE_LINE_MEMBER(keyout_w);
+
+protected:
+	// device-level overrides
+	virtual void device_config_complete() override;
+	virtual void device_resolve_objects() override;
+	virtual void device_start() override;
+
+	// called from keyboard
+	void transmit_data(bool state) { m_keyin_callback(state); }
+	void reset_from_keyboard(bool state) { m_reset_callback(state); }
+
+private:
+	// line callbacks
+	devcb_write_line m_keyin_callback;
+	devcb_write_line m_reset_callback;
+
+	// selected keyboard
+	device_z29_keyboard_interface *m_kbd;
+};
+
+// ======================> device_z29_keyboard_interface
+
+class device_z29_keyboard_interface : public device_interface
+{
+	friend class z29_keyboard_port_device;
+
+protected:
+	// construction/destruction
+	device_z29_keyboard_interface(const machine_config &mconfig, device_t &device);
+	virtual ~device_z29_keyboard_interface();
+
+	void transmit_data(bool state) { m_port->transmit_data(state); }
+	void reset_from_keyboard(bool state) { m_port->reset_from_keyboard(state); }
+
+	virtual void receive_data(bool state) = 0;
+
+private:
+	// parent port
+	required_device<z29_keyboard_port_device> m_port;
+};
+
+// device type definition
+DECLARE_DEVICE_TYPE(Z29_KEYBOARD, z29_keyboard_port_device)
+
+// standard options
+extern void z29_keyboards(device_slot_interface &slot);
+
+//**************************************************************************
+//  INLINE FUNCTIONS
+//**************************************************************************
+
+WRITE_LINE_MEMBER(z29_keyboard_port_device::keyout_w)
+{
+	 if (m_kbd != nullptr)
+		m_kbd->receive_data(state);
+}
+
+#endif // MAME_BUS_Z29_KBD_KEYBOARD_H
diff --git a/src/devices/bus/z29_kbd/md_kbd.cpp b/src/devices/bus/z29_kbd/md_kbd.cpp
new file mode 100644
index 00000000000..1a313af10ce
--- /dev/null
+++ b/src/devices/bus/z29_kbd/md_kbd.cpp
@@ -0,0 +1,277 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+/***************************************************************************
+
+    Micro-Decision keyboard
+
+    This 93-key keyboard was obtained with a Morrow MD3-P. The unit part
+    number is unknown, but "DEKU-0224-PHM-B" and "I/F PCB FOR 14515B" are
+    silkscreened on the component board.
+
+    Like the original Z-29 keyboard, it may also have been designed by
+    Heath/Zenith. It is missing the Erase, Set Up and Break keys (though
+    the first two are still recognized by the program), but has five
+    additional function keys instead.
+
+    Some clumsy coding suggests that the program was originally designed
+    for an 8048 operating in single-chip mode, with the 14515B and LS175
+    having being added to latch outputs also sent to the upper half of
+    Port 2.
+
+***************************************************************************/
+
+#include "emu.h"
+#include "md_kbd.h"
+
+#include "machine/rescap.h"
+#include "speaker.h"
+
+
+DEFINE_DEVICE_TYPE(MD_KEYBOARD, md_keyboard_device, "md_kbd", "Micro-Decision Keyboard")
+
+md_keyboard_device::md_keyboard_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+	: device_t(mconfig, MD_KEYBOARD, tag, owner, clock)
+	, device_z29_keyboard_interface(mconfig, *this)
+	, m_mcu(*this, "mcu")
+	, m_buzzer(*this, "buzzer")
+	, m_matrix(*this, "S%u", 0U)
+	, m_leds(*this, "led%u", 1U)
+	, m_14515b_select(0)
+	, m_ls175_clock(true)
+	, m_recv_data(true)
+{
+}
+
+void md_keyboard_device::device_resolve_objects()
+{
+	m_leds.resolve();
+}
+
+void md_keyboard_device::device_start()
+{
+	save_item(NAME(m_14515b_select));
+	save_item(NAME(m_ls175_clock));
+	save_item(NAME(m_recv_data));
+}
+
+void md_keyboard_device::device_reset()
+{
+	ls175_w(0);
+}
+
+void md_keyboard_device::receive_data(bool state)
+{
+	machine().scheduler().synchronize(timer_expired_delegate(FUNC(md_keyboard_device::receive_data_synced), this), state);
+}
+
+TIMER_CALLBACK_MEMBER(md_keyboard_device::receive_data_synced)
+{
+	m_recv_data = param;
+}
+
+void md_keyboard_device::ls175_w(u8 data)
+{
+	m_leds[0] = !BIT(data, 7); // Caps Lock
+	m_leds[1] = !BIT(data, 5); // Keyboard lock?
+	m_buzzer->set_state(BIT(data, 6));
+}
+
+u8 md_keyboard_device::mcu_p1_r()
+{
+	return 0xc0 | m_matrix[m_14515b_select]->read();
+}
+
+void md_keyboard_device::mcu_p1_w(u8 data)
+{
+	transmit_data(!BIT(data, 7));
+	if (!m_ls175_clock && BIT(data, 6))
+		ls175_w(m_mcu->p2_r());
+	m_ls175_clock = BIT(data, 6);
+}
+
+READ_LINE_MEMBER(md_keyboard_device::mcu_t1_r)
+{
+	return m_recv_data;
+}
+
+void md_keyboard_device::mcu_movx_w(u8 data)
+{
+	m_14515b_select = (data >> 4) & 0x0f;
+}
+
+void md_keyboard_device::prog_map(address_map &map)
+{
+	map(0x000, 0xfff).rom().region("program", 0);
+}
+
+void md_keyboard_device::ext_map(address_map &map)
+{
+	map(0x00, 0x00).mirror(0xff).w(FUNC(md_keyboard_device::mcu_movx_w));
+}
+
+
+static INPUT_PORTS_START(md_kbd)
+
+	PORT_START("S0")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('q') PORT_CHAR('Q') PORT_CODE(KEYCODE_Q)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('g') PORT_CHAR('G') PORT_CODE(KEYCODE_G)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(';') PORT_CHAR(':') PORT_CODE(KEYCODE_COLON)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(0_PAD)) PORT_CODE(KEYCODE_0_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('0') PORT_CHAR(')') PORT_CODE(KEYCODE_0)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Erase") // not actually on keyboard?
+
+	PORT_START("S1")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('w') PORT_CHAR('W') PORT_CODE(KEYCODE_W)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('b') PORT_CHAR('B') PORT_CODE(KEYCODE_B)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(']') PORT_CHAR('}') PORT_CODE(KEYCODE_CLOSEBRACE)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(9_PAD)) PORT_CODE(KEYCODE_9_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('9') PORT_CHAR('(') PORT_CODE(KEYCODE_9)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Help") PORT_CODE(KEYCODE_F12)
+
+	PORT_START("S2")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('e') PORT_CHAR('E') PORT_CODE(KEYCODE_E)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('n') PORT_CHAR('N') PORT_CODE(KEYCODE_N)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('[') PORT_CHAR('{') PORT_CODE(KEYCODE_OPENBRACE)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(8_PAD)) PORT_CODE(KEYCODE_8_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('8') PORT_CHAR('*') PORT_CODE(KEYCODE_8)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Home  Clear") PORT_CHAR(UCHAR_MAMEKEY(HOME)) PORT_CODE(KEYCODE_F11)
+
+	PORT_START("S3")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('r') PORT_CHAR('R') PORT_CODE(KEYCODE_R)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('m') PORT_CHAR('M') PORT_CODE(KEYCODE_M)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('-') PORT_CHAR('_') PORT_CODE(KEYCODE_MINUS)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(7_PAD)) PORT_CODE(KEYCODE_7_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('7') PORT_CHAR('&') PORT_CODE(KEYCODE_7)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_UNUSED)
+
+	PORT_START("S4")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('f') PORT_CHAR('F') PORT_CODE(KEYCODE_F)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('l') PORT_CHAR('L') PORT_CODE(KEYCODE_L)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('=') PORT_CHAR('+') PORT_CODE(KEYCODE_EQUALS)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(6_PAD)) PORT_CODE(KEYCODE_6_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('6') PORT_CHAR('^') PORT_CODE(KEYCODE_6)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("No Scroll") PORT_CODE(KEYCODE_ESC)
+
+	PORT_START("S5")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('d') PORT_CHAR('D') PORT_CODE(KEYCODE_D)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('k') PORT_CHAR('K') PORT_CODE(KEYCODE_K)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('`') PORT_CHAR('~') PORT_CODE(KEYCODE_BACKSLASH) // to right of +/=
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(5_PAD)) PORT_CODE(KEYCODE_5_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('5') PORT_CHAR('%') PORT_CODE(KEYCODE_5)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Caps Lock") PORT_CHAR(UCHAR_MAMEKEY(CAPSLOCK)) PORT_CODE(KEYCODE_CAPSLOCK)
+
+	PORT_START("S6")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('s') PORT_CHAR('S') PORT_CODE(KEYCODE_S)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('j') PORT_CHAR('J') PORT_CODE(KEYCODE_J)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('\'') PORT_CHAR('"') PORT_CODE(KEYCODE_QUOTE)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(4_PAD)) PORT_CODE(KEYCODE_4_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('4') PORT_CHAR('$') PORT_CODE(KEYCODE_4)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Del") PORT_CHAR(UCHAR_MAMEKEY(DEL)) PORT_CODE(KEYCODE_DEL)
+
+	PORT_START("S7")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('a') PORT_CHAR('A') PORT_CODE(KEYCODE_A)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('h') PORT_CHAR('H') PORT_CODE(KEYCODE_H)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('p') PORT_CHAR('P') PORT_CODE(KEYCODE_P)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(3_PAD)) PORT_CODE(KEYCODE_3_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('3') PORT_CHAR('#') PORT_CODE(KEYCODE_3)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(UP)) PORT_CODE(KEYCODE_UP)
+
+	PORT_START("S8")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('z') PORT_CHAR('Z') PORT_CODE(KEYCODE_Z)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('t') PORT_CHAR('T') PORT_CODE(KEYCODE_T)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('o') PORT_CHAR('O') PORT_CODE(KEYCODE_O)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(2_PAD)) PORT_CODE(KEYCODE_2_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('2') PORT_CHAR('@') PORT_CODE(KEYCODE_2)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(DOWN)) PORT_CODE(KEYCODE_DOWN)
+
+	PORT_START("S9")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('x') PORT_CHAR('X') PORT_CODE(KEYCODE_X)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('y') PORT_CHAR('Y') PORT_CODE(KEYCODE_Y)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('\\') PORT_CHAR('|') PORT_CODE(KEYCODE_RCONTROL)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(1_PAD)) PORT_CODE(KEYCODE_1_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('1') PORT_CHAR('!') PORT_CODE(KEYCODE_1)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(RIGHT)) PORT_CODE(KEYCODE_RIGHT)
+
+	PORT_START("S10")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('c') PORT_CHAR('C') PORT_CODE(KEYCODE_C)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('u') PORT_CHAR('U') PORT_CODE(KEYCODE_U)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(',') PORT_CHAR('<') PORT_CODE(KEYCODE_COMMA)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(COMMA_PAD)) PORT_CODE(KEYCODE_PLUS_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Esc") PORT_CHAR(0x1b) PORT_CODE(KEYCODE_TILDE)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(LEFT)) PORT_CODE(KEYCODE_LEFT)
+
+	PORT_START("S11")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('v') PORT_CHAR('V') PORT_CODE(KEYCODE_V)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('i') PORT_CHAR('I') PORT_CODE(KEYCODE_I)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('.') PORT_CHAR('>') PORT_CODE(KEYCODE_STOP)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(DEL_PAD)) PORT_CODE(KEYCODE_DEL_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Tab") PORT_CHAR('\t') PORT_CODE(KEYCODE_TAB)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR('/') PORT_CHAR('?') PORT_CODE(KEYCODE_SLASH)
+
+	PORT_START("S12")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(' ') PORT_CODE(KEYCODE_SPACE)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Return") PORT_CHAR(0x0d) PORT_CODE(KEYCODE_ENTER)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Keypad Enter  +") PORT_CHAR(UCHAR_MAMEKEY(ENTER_PAD)) PORT_CODE(KEYCODE_ENTER_PAD)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(MINUS_PAD)) PORT_CODE(KEYCODE_MINUS_PAD)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Line Feed") PORT_CHAR(0x0a) PORT_CODE(KEYCODE_RALT)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Back Space") PORT_CHAR(0x08) PORT_CODE(KEYCODE_BACKSPACE)
+
+	PORT_START("S13")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F1)) PORT_CODE(KEYCODE_F1)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F2)) PORT_CODE(KEYCODE_F2)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F3)) PORT_CODE(KEYCODE_F3)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F4)) PORT_CODE(KEYCODE_F4)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F5)) PORT_CODE(KEYCODE_F5)
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F6)) PORT_CODE(KEYCODE_F6)
+
+	PORT_START("S14")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F7)) PORT_CODE(KEYCODE_F7)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F8)) PORT_CODE(KEYCODE_F8)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F9)) PORT_CODE(KEYCODE_F9)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CHAR(UCHAR_MAMEKEY(F10)) PORT_CODE(KEYCODE_F10)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("FA") PORT_CHAR(UCHAR_MAMEKEY(F11))
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("FB") PORT_CHAR(UCHAR_MAMEKEY(F12))
+
+	PORT_START("S15")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Setup") // not actually on keyboard?
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("FD") PORT_CHAR(UCHAR_MAMEKEY(F14))
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("FC") PORT_CHAR(UCHAR_MAMEKEY(F13))
+
+	PORT_START("MODIFIERS")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Ctrl") PORT_CHAR(UCHAR_SHIFT_2) PORT_CODE(KEYCODE_LCONTROL)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_NAME("Shift") PORT_CHAR(UCHAR_SHIFT_1) PORT_CODE(KEYCODE_LSHIFT) PORT_CODE(KEYCODE_RSHIFT)
+INPUT_PORTS_END
+
+ioport_constructor md_keyboard_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME(md_kbd);
+}
+
+void md_keyboard_device::device_add_mconfig(machine_config &config)
+{
+	// U4 is M5L8048-052P (internal ROM likely unused), but location is silkscreened "8035"
+	I8035(config, m_mcu, 3.579545_MHz_XTAL); // "CSA 3 58MT" resonator
+	m_mcu->set_addrmap(AS_PROGRAM, &md_keyboard_device::prog_map);
+	m_mcu->set_addrmap(AS_IO, &md_keyboard_device::ext_map);
+	m_mcu->p1_in_cb().set(FUNC(md_keyboard_device::mcu_p1_r));
+	m_mcu->p1_out_cb().set(FUNC(md_keyboard_device::mcu_p1_w));
+	m_mcu->p2_in_cb().set_ioport("MODIFIERS");
+	m_mcu->t1_in_cb().set(FUNC(md_keyboard_device::mcu_t1_r));
+
+	SPEAKER(config, "speaker").front_center();
+	BEEP(config, m_buzzer, 1'000'000'000 / PERIOD_OF_555_ASTABLE_NSEC(RES_R(510), RES_R(510), CAP_U(1)));
+	m_buzzer->add_route(ALL_OUTPUTS, "speaker", 1.0);
+}
+
+ROM_START(md_kbd)
+	ROM_REGION(0x1000, "program", 0)
+	ROM_LOAD("kb-rom_rev_3.4_27d4.u5", 0x0000, 0x1000, CRC(c34b606b) SHA1(20cf62fc31257b6c3e767152086f2604fead97bd)) // location marked "2716/2732"
+ROM_END
+
+const tiny_rom_entry *md_keyboard_device::device_rom_region() const
+{
+	return ROM_NAME(md_kbd);
+}
diff --git a/src/devices/bus/z29_kbd/md_kbd.h b/src/devices/bus/z29_kbd/md_kbd.h
new file mode 100644
index 00000000000..8a81b9a461d
--- /dev/null
+++ b/src/devices/bus/z29_kbd/md_kbd.h
@@ -0,0 +1,61 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+
+#ifndef MAME_BUS_Z29_KBD_MD_KBD_H
+#define MAME_BUS_Z29_KBD_MD_KBD_H
+
+#pragma once
+
+#include "keyboard.h"
+#include "cpu/mcs48/mcs48.h"
+#include "sound/beep.h"
+
+class md_keyboard_device : public device_t, public device_z29_keyboard_interface
+{
+public:
+	// device type constructor
+	md_keyboard_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock);
+
+protected:
+	// device-level overrides
+	virtual void device_resolve_objects() override;
+	virtual void device_start() override;
+	virtual void device_reset() override;
+	virtual ioport_constructor device_input_ports() const override;
+	virtual void device_add_mconfig(machine_config &config) override;
+	virtual const tiny_rom_entry *device_rom_region() const override;
+
+	// device_z29_keyboard_interface overrides
+	virtual void receive_data(bool state) override;
+
+private:
+	// MCU handlers
+	u8 mcu_p1_r();
+	void mcu_p1_w(u8 data);
+	DECLARE_READ_LINE_MEMBER(mcu_t1_r);
+	void mcu_movx_w(u8 data);
+
+	// misc. helpers
+	TIMER_CALLBACK_MEMBER(receive_data_synced);
+	void ls175_w(u8 data);
+
+	// address maps
+	void prog_map(address_map &map);
+	void ext_map(address_map &map);
+
+	// object finders
+	required_device<mcs48_cpu_device> m_mcu;
+	required_device<beep_device> m_buzzer;
+	required_ioport_array<16> m_matrix;
+	output_finder<2> m_leds;
+
+	// internal state
+	u8 m_14515b_select;
+	bool m_ls175_clock;
+	bool m_recv_data;
+};
+
+// device type declaration
+DECLARE_DEVICE_TYPE(MD_KEYBOARD, md_keyboard_device)
+
+#endif // MAME_BUS_Z29_KBD_MD_KBD_H
diff --git a/src/mame/drivers/mdt60.cpp b/src/mame/drivers/mdt60.cpp
index 493ee5daf07..90ef746f92a 100644
--- a/src/mame/drivers/mdt60.cpp
+++ b/src/mame/drivers/mdt60.cpp
@@ -2,58 +2,41 @@
 // copyright-holders:AJR
 /**************************************************************************
 
-    Skeleton driver for MDT 60 and related Zenith terminals.
-
     MDT 60 was designed by Zenith for use with Morrow's Micro-Decision
     computers as a low-cost terminal with limited features. It appears
     to be a stripped-down version of some previously designed terminal,
     with the auxiliary port omitted from the Morrow version even though
-    the schematics published by Morrow include it. Morrow's schematics
-    also include the same keyboard used by the Z-29, though the actual
-    keyboard found with one unit was different.
+    the schematics published in its service manual include it. These
+    schematics also include the same keyboard used by the Z-29, though
+    the actual keyboard found with one unit was different.
 
 **************************************************************************/
 
 #include "emu.h"
 #include "bus/rs232/rs232.h"
+#include "bus/z29_kbd/keyboard.h"
 #include "cpu/m6502/m6502.h"
-#include "machine/eepromser.h"
 #include "machine/i8251.h"
-#include "machine/pit8253.h"
 #include "video/mc6845.h"
 #include "screen.h"
 
-class mdt60_base_state : public driver_device
-{
-public:
-	mdt60_base_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag)
-		, m_maincpu(*this, "maincpu")
-		, m_crtc(*this, "crtc")
-		, m_uart(*this, "uart%u", 0U)
-		, m_charram(*this, "charram")
-	{
-	}
-
-protected:
-	MC6845_ON_UPDATE_ADDR_CHANGED(update_cb);
-
-	required_device<cpu_device> m_maincpu;
-	required_device<r6545_1_device> m_crtc;
-	optional_device_array<i8251_device, 2> m_uart;
-	required_shared_ptr<u8> m_charram;
-};
-
-class mdt60_state : public mdt60_base_state
+class mdt60_state : public driver_device
 {
 public:
 	mdt60_state(const machine_config &mconfig, device_type type, const char *tag)
-		: mdt60_base_state(mconfig, type, tag)
+		: driver_device(mconfig, type, tag)
+		, m_maincpu(*this, "maincpu")
+		, m_keyboard(*this, "keyboard")
+		, m_crtc(*this, "crtc")
+		, m_uart(*this, "uart%u", 0U)
+		, m_charram(*this, "charram")
 		, m_charrom(*this, "charrom")
 		, m_attrram(*this, "attrram")
 		, m_dip0(*this, "DIP0")
+		, m_baud_timer(nullptr)
 		, m_keyin(false)
-		, m_reverse(false)
+		, m_output_reg(0x3f)
+		, m_timer_output(false)
 	{
 	}
 
@@ -65,6 +48,8 @@ protected:
 
 private:
 	MC6845_UPDATE_ROW(update_row);
+	MC6845_ON_UPDATE_ADDR_CHANGED(update_cb);
+	TIMER_CALLBACK_MEMBER(baud_timer);
 
 	DECLARE_WRITE_LINE_MEMBER(keyin_w);
 	u8 dip0_r(offs_t offset);
@@ -72,54 +57,30 @@ private:
 
 	void mem_map(address_map &map);
 
+	required_device<cpu_device> m_maincpu;
+	required_device<z29_keyboard_port_device> m_keyboard;
+	required_device<r6545_1_device> m_crtc;
+	optional_device_array<i8251_device, 2> m_uart;
+	required_shared_ptr<u8> m_charram;
 	required_region_ptr<u8> m_charrom;
 	required_shared_ptr<u8> m_attrram;
 	required_ioport m_dip0;
 
+	emu_timer *m_baud_timer;
+
 	bool m_keyin;
-	bool m_reverse;
-};
-
-class z22_state : public mdt60_base_state
-{
-public:
-	z22_state(const machine_config &mconfig, device_type type, const char *tag)
-		: mdt60_base_state(mconfig, type, tag)
-		, m_eeprom(*this, "eeprom")
-		, m_fontram(*this, "fontram")
-		, m_eeprom_clk(false)
-	{
-	}
-
-	void z22(machine_config &config);
-
-protected:
-	virtual void machine_start() override;
-
-private:
-	MC6845_UPDATE_ROW(update_row);
-
-	u8 status_r();
-	void control_w(u8 data);
-	DECLARE_WRITE_LINE_MEMBER(eeprom_clock_w);
-
-	void mem_map(address_map &map);
-
-	required_device<eeprom_serial_93cxx_device> m_eeprom;
-	required_shared_ptr<u8> m_fontram;
-
-	bool m_eeprom_clk;
+	u8 m_output_reg;
+	bool m_timer_output;
 };
 
 void mdt60_state::machine_start()
 {
-	save_item(NAME(m_keyin));
-	save_item(NAME(m_reverse));
-}
+	m_baud_timer = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(mdt60_state::baud_timer), this));
+	m_baud_timer->adjust(attotime::zero);
 
-void z22_state::machine_start()
-{
-	save_item(NAME(m_eeprom_clk));
+	save_item(NAME(m_keyin));
+	save_item(NAME(m_output_reg));
+	save_item(NAME(m_timer_output));
 }
 
 void mdt60_state::machine_reset()
@@ -128,6 +89,23 @@ void mdt60_state::machine_reset()
 }
 
 
+TIMER_CALLBACK_MEMBER(mdt60_state::baud_timer)
+{
+	m_timer_output = !m_timer_output;
+
+	// LS352 multiplexer has inverting outputs
+	m_uart[0]->write_rxc(!m_timer_output);
+	m_uart[0]->write_txc(!m_timer_output);
+
+	constexpr auto time_base = 16.5888_MHz_XTAL / 9;
+	if ((m_output_reg & 0x06) == 0x00)
+		m_baud_timer->adjust(attotime::from_ticks(m_timer_output ? 2 : 4, time_base));
+	else if ((m_output_reg & 0x06) == 0x06)
+		m_baud_timer->adjust(attotime::from_ticks(48, time_base));
+	else
+		m_baud_timer->adjust(attotime::from_ticks(3 * (m_output_reg & 0x06), time_base));
+}
+
 MC6845_UPDATE_ROW(mdt60_state::update_row)
 {
 	u32 *pix = &bitmap.pix32(y);
@@ -147,7 +125,7 @@ MC6845_UPDATE_ROW(mdt60_state::update_row)
 
 		rgb_t fg = BIT(adata, 1) ? rgb_t::white() : rgb_t(0xc0, 0xc0, 0xc0);
 		rgb_t bg = rgb_t::black();
-		if (m_reverse)
+		if (BIT(m_output_reg, 5))
 			std::swap(fg, bg);
 
 		for (int n = 8; n >= 0; n--)
@@ -155,27 +133,7 @@ MC6845_UPDATE_ROW(mdt60_state::update_row)
 	}
 }
 
-MC6845_UPDATE_ROW(z22_state::update_row)
-{
-	u32 *pix = &bitmap.pix32(y);
-
-	for (unsigned x = 0; x < x_count; x++)
-	{
-		u8 cdata = m_charram[(ma + x) & 0x7ff];
-		u16 dots = m_fontram[(cdata & 0x7f) << 4 | ra] << 1;
-
-		if (x == cursor_x)
-			dots = ~dots;
-
-		rgb_t fg = rgb_t::white();
-		rgb_t bg = rgb_t::black();
-
-		for (int n = 8; n >= 0; n--)
-			*pix++ = BIT(dots, n) ? fg : bg;
-	}
-}
-
-MC6845_ON_UPDATE_ADDR_CHANGED(mdt60_base_state::update_cb)
+MC6845_ON_UPDATE_ADDR_CHANGED(mdt60_state::update_cb)
 {
 }
 
@@ -190,9 +148,9 @@ u8 mdt60_state::dip0_r(offs_t offset)
 {
 	u8 buffer = 0xff;
 	if (!BIT(offset, 0))
-		buffer &= m_dip0->read() | 0x80;
+		buffer &= m_dip0->read() >> 1 | 0x80;
 	if (!BIT(offset, 1))
-		buffer &= m_dip0->read() >> 7 | 0xfe;
+		buffer &= m_dip0->read() | 0xfe;
 	if (!m_keyin)
 		buffer &= 0x7f;
 	return buffer;
@@ -200,29 +158,11 @@ u8 mdt60_state::dip0_r(offs_t offset)
 
 void mdt60_state::reg_w(u8 data)
 {
-	//m_keyboard->keyout_w(BIT(data, 0));
-	m_reverse = BIT(data, 5);
-}
+	if (BIT(data, 0) != BIT(m_output_reg, 0))
+		m_keyboard->keyout_w(BIT(data, 0));
 
-u8 z22_state::status_r()
-{
-	u8 result = 0;
-	if (m_eeprom_clk)
-		result |= 0x02;
-	if (!m_eeprom->do_read())
-		result |= 0x01;
-	return result;
-}
-
-void z22_state::control_w(u8 data)
-{
-	m_eeprom->di_write(!BIT(data, 7));
-	m_eeprom->cs_write(BIT(data, 6));
-}
-
-WRITE_LINE_MEMBER(z22_state::eeprom_clock_w)
-{
-	m_eeprom_clk = state;
+	// Bits 1–2 & 3–4 select 1 of 4 baud rates for each UART; bit 5 selects inverse video
+	m_output_reg = data & 0x3f;
 }
 
 void mdt60_state::mem_map(address_map &map)
@@ -240,23 +180,9 @@ void mdt60_state::mem_map(address_map &map)
 	map(0xe000, 0xefff).mirror(0x1000).rom().region("coderom", 0);
 }
 
-void z22_state::mem_map(address_map &map)
-{
-	map(0x0000, 0x07ff).ram();
-	map(0x2000, 0x27ff).ram().share("charram");
-	map(0x4000, 0x4001).rw(m_uart[1], FUNC(i8251_device::read), FUNC(i8251_device::write));
-	map(0x6000, 0x67ff).ram().share("fontram");
-	map(0x8000, 0x8001).rw(m_uart[0], FUNC(i8251_device::read), FUNC(i8251_device::write));
-	map(0x8800, 0x8800).rw(m_crtc, FUNC(r6545_1_device::status_r), FUNC(r6545_1_device::address_w));
-	map(0x8801, 0x8801).rw(m_crtc, FUNC(r6545_1_device::register_r), FUNC(r6545_1_device::register_w));
-	map(0x9000, 0x9003).w("pit", FUNC(pit8254_device::write));
-	map(0xa000, 0xa000).rw(FUNC(z22_state::status_r), FUNC(z22_state::control_w));
-	map(0xc000, 0xffff).rom().region("program", 0);
-}
-
 
 static INPUT_PORTS_START(mdt60)
-	PORT_START("DIP0") // TODO: verify bit assignments
+	PORT_START("DIP0")
 	PORT_DIPNAME(0x03, 0x01, "Baud Rate") PORT_DIPLOCATION("SW1:1,2")
 	PORT_DIPSETTING(0x03, "300")
 	PORT_DIPSETTING(0x02, "1200")
@@ -284,9 +210,6 @@ static INPUT_PORTS_START(mdt60)
 	PORT_BIT(0xff, 0xff, IPT_UNUSED) // SW2 is unpopulated
 INPUT_PORTS_END
 
-static INPUT_PORTS_START(z22)
-INPUT_PORTS_END
-
 // XTAL frequency is specified as 16.589 MHz on actual parts as well as in MDT 60 schematics.
 // This has been assumed to be a lower-precision specification of the common 16.5888 MHz value.
 
@@ -297,12 +220,15 @@ void mdt60_state::mdt60(machine_config &config)
 
 	I8251(config, m_uart[0], 16.5888_MHz_XTAL / 9); // TMP8251AP (U19)
 	m_uart[0]->rxrdy_handler().set_inputline(m_maincpu, m6512_device::NMI_LINE);
-	m_uart[0]->txd_handler().set("computer", FUNC(rs232_port_device::write_txd));
-	m_uart[0]->dtr_handler().set("computer", FUNC(rs232_port_device::write_dtr));
-	m_uart[0]->rts_handler().set("computer", FUNC(rs232_port_device::write_rts));
+	m_uart[0]->txd_handler().set("comm", FUNC(rs232_port_device::write_txd));
+	m_uart[0]->dtr_handler().set("comm", FUNC(rs232_port_device::write_dtr));
+	m_uart[0]->rts_handler().set("comm", FUNC(rs232_port_device::write_rts));
 
 	// UART 1 (at U28) is unpopulated and not used by code
 
+	Z29_KEYBOARD(config, m_keyboard, z29_keyboards, "md");
+	m_keyboard->keyin_callback().set(FUNC(mdt60_state::keyin_w)).invert();
+
 	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
 	screen.set_color(rgb_t::amber());
 	screen.set_raw(16.5888_MHz_XTAL, 918, 0, 720, 301, 0, 288);
@@ -314,54 +240,10 @@ void mdt60_state::mdt60(machine_config &config)
 	m_crtc->set_char_width(9);
 	m_crtc->set_update_row_callback(FUNC(mdt60_state::update_row));
 	m_crtc->set_on_update_addr_change_callback(FUNC(mdt60_state::update_cb));
+	// LPEN is tied to GND (code uses this to determine CRTC type)
 
-	rs232_port_device &computer(RS232_PORT(config, "computer", default_rs232_devices, nullptr));
-	computer.rxd_handler().set(m_uart[0], FUNC(i8251_device::write_rxd));
-	computer.dsr_handler().set(m_uart[0], FUNC(i8251_device::write_dsr));
-	computer.cts_handler().set(m_uart[0], FUNC(i8251_device::write_cts));
-}
-
-void z22_state::z22(machine_config &config)
-{
-	M6512(config, m_maincpu, 16.5888_MHz_XTAL / 9); // R6512AP
-	m_maincpu->set_addrmap(AS_PROGRAM, &z22_state::mem_map);
-
-	I8251(config, m_uart[0], 16.5888_MHz_XTAL / 9); // NEC D8251AC (U33) + Intel P8251A (U35)
-	m_uart[0]->rxrdy_handler().set_inputline(m_maincpu, m6512_device::NMI_LINE);
-	m_uart[0]->txd_handler().set("comm", FUNC(rs232_port_device::write_txd));
-	m_uart[0]->dtr_handler().set("comm", FUNC(rs232_port_device::write_dtr));
-	m_uart[0]->rts_handler().set("comm", FUNC(rs232_port_device::write_rts));
-
-	I8251(config, m_uart[1], 16.5888_MHz_XTAL / 9);
-
-	EEPROM_93C06_16BIT(config, m_eeprom); // NMC9306 (U27)
-
-	pit8254_device &pit(PIT8254(config, "pit")); // Intel P8254
-	pit.set_clk<0>(16.5888_MHz_XTAL / 9);
-	pit.set_clk<1>(16.5888_MHz_XTAL / 9);
-	pit.set_clk<2>(16.5888_MHz_XTAL / 9);
-	pit.out_handler<0>().set(m_uart[1], FUNC(i8251_device::write_rxc));
-	pit.out_handler<0>().append(m_uart[1], FUNC(i8251_device::write_txc));
-	pit.out_handler<0>().append(m_eeprom, FUNC(eeprom_serial_93cxx_device::clk_write)); // weird synchronous clocking
-	pit.out_handler<0>().append(FUNC(z22_state::eeprom_clock_w));
-	pit.out_handler<1>().set(m_uart[0], FUNC(i8251_device::write_rxc));
-	pit.out_handler<2>().set(m_uart[0], FUNC(i8251_device::write_txc)); // or the other way around?
-
-	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
-	screen.set_color(rgb_t::amber());
-	screen.set_raw(16.5888_MHz_XTAL, 873, 0, 720, 317, 0, 300);
-	screen.set_screen_update(m_crtc, FUNC(r6545_1_device::screen_update));
-
-	R6545_1(config, m_crtc, 16.5888_MHz_XTAL / 9); // R6545-1AP
-	m_crtc->set_screen("screen");
-	m_crtc->set_show_border_area(false);
-	m_crtc->set_char_width(9);
-	m_crtc->set_update_row_callback(FUNC(z22_state::update_row));
-	m_crtc->set_on_update_addr_change_callback(FUNC(z22_state::update_cb));
-
-	// TODO: onboard buzzer
-
-	rs232_port_device &comm(RS232_PORT(config, "comm", default_rs232_devices, nullptr));
+	rs232_port_device &comm(RS232_PORT(config, "comm", default_rs232_devices, "loopback"));
+	// Service Manual suggests shorting pins with a bent paper clip if no DB-25 loopback connector is available ;-)
 	comm.rxd_handler().set(m_uart[0], FUNC(i8251_device::write_rxd));
 	comm.dsr_handler().set(m_uart[0], FUNC(i8251_device::write_dsr));
 	comm.cts_handler().set(m_uart[0], FUNC(i8251_device::write_cts));
@@ -370,17 +252,11 @@ void z22_state::z22(machine_config &config)
 
 ROM_START(mdt60)
 	ROM_REGION(0x1000, "coderom", 0)
+	// "ROM REV. 1.7 -- Copyright (C) 1983 by Morrow Designs, Inc."
 	ROM_LOAD("vb-rom_1.7_bcfd.u9", 0x0000, 0x1000, CRC(3902f7b3) SHA1(ee0ce7f68efe20efe1ab8a44888e276f08fe2d07))
 
 	ROM_REGION(0x1000, "charrom", 0)
 	ROM_LOAD("char_gen_b207.u6", 0x0000, 0x1000, CRC(b19432da) SHA1(fa73641c08b778f19a17676a7f4074f69b7b55dd))
 ROM_END
 
-ROM_START(z22)
-	ROM_REGION(0x4000, "program", 0)
-	ROM_LOAD("u39.bin", 0x0000, 0x2000, CRC(2f62c1f8) SHA1(448581d987fee6b4303e481e78f46d3255baccbb)) // D2764A-3
-	ROM_LOAD("u38.bin", 0x2000, 0x2000, CRC(f0bfe9b5) SHA1(8807841b28549d0ddf30275fc6035a66093f8768)) // D2764A-3
-ROM_END
-
-SYST(1983, mdt60, 0, 0, mdt60, mdt60, mdt60_state, empty_init, "Morrow", "MDT 60 Video Display Terminal", MACHINE_NOT_WORKING | MACHINE_NO_SOUND)
-SYST(1984, z22, 0, 0, z22, z22, z22_state, empty_init, "Zenith Data Systems", "Z-22 Terminal", MACHINE_NOT_WORKING | MACHINE_NO_SOUND)
+SYST(1983, mdt60, 0, 0, mdt60, mdt60, mdt60_state, empty_init, "Morrow Designs", "MDT 60 Video Display Terminal", MACHINE_SUPPORTS_SAVE)
diff --git a/src/mame/drivers/z22.cpp b/src/mame/drivers/z22.cpp
new file mode 100644
index 00000000000..7421bf9ad16
--- /dev/null
+++ b/src/mame/drivers/z22.cpp
@@ -0,0 +1,215 @@
+// license:BSD-3-Clause
+// copyright-holders:AJR
+/**************************************************************************
+
+    Skeleton driver for Zenith Z-22 terminal.
+
+    Despite featuring much of the same hardware as the MDT 60, with the
+    CPU, CRTC and UART types and even dot clock frequency being identical,
+    much else is different: a serial EEPROM replaces DIP switches, an 8254
+    generates baud rates, fonts are uploaded to RAM, and the serial
+    keyboard protocol is incompatible.
+
+**************************************************************************/
+
+#include "emu.h"
+#include "bus/rs232/rs232.h"
+#include "cpu/m6502/m6502.h"
+#include "machine/eepromser.h"
+#include "machine/i8251.h"
+#include "machine/pit8253.h"
+#include "video/mc6845.h"
+#include "screen.h"
+
+class z22_state : public driver_device
+{
+public:
+	z22_state(const machine_config &mconfig, device_type type, const char *tag)
+		: driver_device(mconfig, type, tag)
+		, m_maincpu(*this, "maincpu")
+		, m_crtc(*this, "crtc")
+		, m_uart(*this, "uart%u", 0U)
+		, m_eeprom(*this, "eeprom")
+		, m_dispram(*this, "dispram")
+		, m_fontram(*this, "fontram")
+		, m_eeprom_clk(false)
+	{
+	}
+
+	void z22(machine_config &config);
+
+protected:
+	virtual void machine_start() override;
+	virtual void machine_reset() override;
+
+private:
+	MC6845_UPDATE_ROW(update_row);
+	MC6845_ON_UPDATE_ADDR_CHANGED(update_cb);
+
+	u8 irq_ack_r();
+	u8 status_r();
+	void control_w(u8 data);
+
+	DECLARE_WRITE_LINE_MEMBER(eeprom_clock_w);
+
+	void mem_map(address_map &map);
+
+	required_device<cpu_device> m_maincpu;
+	required_device<r6545_1_device> m_crtc;
+	optional_device_array<i8251_device, 2> m_uart;
+	required_device<eeprom_serial_93cxx_device> m_eeprom;
+	required_shared_ptr<u8> m_dispram;
+	required_shared_ptr<u8> m_fontram;
+
+	bool m_eeprom_clk;
+};
+
+void z22_state::machine_start()
+{
+	save_item(NAME(m_eeprom_clk));
+}
+
+void z22_state::machine_reset()
+{
+	control_w(0);
+}
+
+
+MC6845_UPDATE_ROW(z22_state::update_row)
+{
+	u32 *pix = &bitmap.pix32(y);
+
+	for (unsigned x = 0; x < x_count; x++)
+	{
+		u8 cdata = m_dispram[(ma + x) & 0x7ff];
+		u16 dots = m_fontram[(cdata & 0x7f) << 4 | ra] << 1;
+
+		if (x == cursor_x)
+			dots = ~dots;
+
+		rgb_t fg = rgb_t::white();
+		rgb_t bg = rgb_t::black();
+
+		for (int n = 8; n >= 0; n--)
+			*pix++ = BIT(dots, n) ? fg : bg;
+	}
+}
+
+MC6845_ON_UPDATE_ADDR_CHANGED(z22_state::update_cb)
+{
+}
+
+
+u8 z22_state::irq_ack_r()
+{
+	if (!machine().side_effects_disabled())
+		m_maincpu->set_input_line(m6512_device::IRQ_LINE, CLEAR_LINE);
+	return 0xff;
+}
+
+u8 z22_state::status_r()
+{
+	u8 result = 0;
+	if (!m_eeprom->do_read())
+		result |= 0x01;
+	if (m_eeprom_clk)
+		result |= 0x02;
+	// TODO: bit 7 = received keyboard data
+	return result;
+}
+
+void z22_state::control_w(u8 data)
+{
+	m_eeprom->di_write(!BIT(data, 7));
+	m_eeprom->cs_write(BIT(data, 6));
+	//m_keyboard->keyout_w(BIT(data, 0));
+}
+
+WRITE_LINE_MEMBER(z22_state::eeprom_clock_w)
+{
+	m_eeprom_clk = state;
+	if (state)
+		m_maincpu->set_input_line(m6512_device::IRQ_LINE, ASSERT_LINE);
+}
+
+void z22_state::mem_map(address_map &map)
+{
+	map(0x0000, 0x07ff).ram();
+	map(0x2000, 0x27ff).ram().share("dispram");
+	map(0x4000, 0x4001).rw(m_uart[1], FUNC(i8251_device::read), FUNC(i8251_device::write));
+	map(0x6000, 0x67ff).ram().share("fontram");
+	map(0x8000, 0x8001).rw(m_uart[0], FUNC(i8251_device::read), FUNC(i8251_device::write));
+	map(0x8800, 0x8800).rw(m_crtc, FUNC(r6545_1_device::status_r), FUNC(r6545_1_device::address_w));
+	map(0x8801, 0x8801).rw(m_crtc, FUNC(r6545_1_device::register_r), FUNC(r6545_1_device::register_w));
+	map(0x9000, 0x9003).w("pit", FUNC(pit8254_device::write));
+	map(0x9800, 0x9800).r(FUNC(z22_state::irq_ack_r));
+	map(0xa000, 0xa000).rw(FUNC(z22_state::status_r), FUNC(z22_state::control_w));
+	map(0xc000, 0xffff).rom().region("program", 0);
+}
+
+
+static INPUT_PORTS_START(z22)
+INPUT_PORTS_END
+
+// XTAL frequency is specified as 16.589 MHz on actual parts. As with the MDT 60, this
+// has been assumed to be a lower-precision specification of the common 16.5888 MHz value.
+
+void z22_state::z22(machine_config &config)
+{
+	M6512(config, m_maincpu, 16.5888_MHz_XTAL / 9); // R6512AP
+	m_maincpu->set_addrmap(AS_PROGRAM, &z22_state::mem_map);
+
+	I8251(config, m_uart[0], 16.5888_MHz_XTAL / 9); // NEC D8251AC (U33) + Intel P8251A (U35)
+	m_uart[0]->rxrdy_handler().set_inputline(m_maincpu, m6512_device::NMI_LINE);
+	m_uart[0]->txd_handler().set("comm", FUNC(rs232_port_device::write_txd));
+	m_uart[0]->dtr_handler().set("comm", FUNC(rs232_port_device::write_dtr));
+	m_uart[0]->rts_handler().set("comm", FUNC(rs232_port_device::write_rts));
+
+	I8251(config, m_uart[1], 16.5888_MHz_XTAL / 9);
+	m_uart[1]->txd_handler().set("printer", FUNC(rs232_port_device::write_txd));
+
+	EEPROM_93C06_16BIT(config, m_eeprom); // NMC9306 (U27)
+
+	pit8254_device &pit(PIT8254(config, "pit")); // Intel P8254
+	pit.set_clk<0>(16.5888_MHz_XTAL / 9);
+	pit.set_clk<1>(16.5888_MHz_XTAL / 9);
+	pit.set_clk<2>(16.5888_MHz_XTAL / 9);
+	pit.out_handler<0>().set(m_eeprom, FUNC(eeprom_serial_93cxx_device::clk_write)); // weird synchronous clocking
+	pit.out_handler<0>().append(FUNC(z22_state::eeprom_clock_w));
+	pit.out_handler<1>().set(m_uart[0], FUNC(i8251_device::write_rxc));
+	pit.out_handler<2>().set(m_uart[0], FUNC(i8251_device::write_txc)); // or the other way around?
+	pit.out_handler<2>().append(m_uart[1], FUNC(i8251_device::write_txc));
+
+	// TODO: Keyboard (asynchronous serial, like Z-49?)
+
+	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
+	screen.set_color(rgb_t::amber());
+	screen.set_raw(16.5888_MHz_XTAL, 873, 0, 720, 317, 0, 300);
+	screen.set_screen_update(m_crtc, FUNC(r6545_1_device::screen_update));
+
+	R6545_1(config, m_crtc, 16.5888_MHz_XTAL / 9); // R6545-1AP
+	m_crtc->set_screen("screen");
+	m_crtc->set_show_border_area(false);
+	m_crtc->set_char_width(9);
+	m_crtc->set_update_row_callback(FUNC(z22_state::update_row));
+	m_crtc->set_on_update_addr_change_callback(FUNC(z22_state::update_cb));
+
+	// TODO: onboard buzzer
+
+	rs232_port_device &comm(RS232_PORT(config, "comm", default_rs232_devices, nullptr));
+	comm.rxd_handler().set(m_uart[0], FUNC(i8251_device::write_rxd));
+	comm.dsr_handler().set(m_uart[0], FUNC(i8251_device::write_dsr));
+	comm.cts_handler().set(m_uart[0], FUNC(i8251_device::write_cts));
+
+	rs232_port_device &printer(RS232_PORT(config, "printer", default_rs232_devices, nullptr));
+	printer.dsr_handler().set(m_uart[1], FUNC(i8251_device::write_dsr));
+}
+
+
+ROM_START(z22)
+	ROM_REGION(0x4000, "program", 0)
+	ROM_LOAD("u39.bin", 0x0000, 0x2000, CRC(2f62c1f8) SHA1(448581d987fee6b4303e481e78f46d3255baccbb)) // D2764A-3
+	ROM_LOAD("u38.bin", 0x2000, 0x2000, CRC(f0bfe9b5) SHA1(8807841b28549d0ddf30275fc6035a66093f8768)) // D2764A-3
+ROM_END
+
+SYST(1984, z22, 0, 0, z22, z22, z22_state, empty_init, "Zenith Data Systems", "Z-22 Terminal", MACHINE_NOT_WORKING | MACHINE_NO_SOUND)
diff --git a/src/mame/drivers/z29.cpp b/src/mame/drivers/z29.cpp
index b491c3abe06..37098f75af6 100644
--- a/src/mame/drivers/z29.cpp
+++ b/src/mame/drivers/z29.cpp
@@ -8,8 +8,8 @@
 
 #include "emu.h"
 //#include "bus/rs232/rs232.h"
+#include "bus/z29_kbd/keyboard.h"
 #include "cpu/mcs51/mcs51.h"
-#include "cpu/mcs48/mcs48.h"
 #include "machine/x2212.h"
 #include "video/i8275.h"
 #include "screen.h"
@@ -20,11 +20,14 @@ public:
 	z29_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag)
 		, m_maincpu(*this, "maincpu")
+		, m_keyboard(*this, "keyboard")
 		, m_crtc(*this, "crtc%u", 1U)
 		, m_nvram(*this, "nvram")
 		, m_charmem(*this, "charmem")
 		, m_attrmem(*this, "attrmem")
 		, m_chargen(*this, "chargen")
+		, m_dmatype(true)
+		, m_keyin(true)
 	{
 	}
 
@@ -34,8 +37,10 @@ protected:
 	virtual void machine_start() override;
 
 private:
+	DECLARE_WRITE_LINE_MEMBER(keyin_w);
+	u8 p1_r();
 	void p3_w(u8 data);
-	DECLARE_READ8_MEMBER(bs_24k_r);
+	u8 bs_24k_r(offs_t offset);
 	void crtc_w(offs_t offset, u8 data);
 	void latch_12k_w(u8 data);
 
@@ -43,6 +48,7 @@ private:
 	void ext_map(address_map &map);
 
 	required_device<mcs51_cpu_device> m_maincpu;
+	required_device<z29_keyboard_port_device> m_keyboard;
 	required_device_array<i8276_device, 2> m_crtc;
 	required_device<x2210_device> m_nvram;
 
@@ -51,11 +57,23 @@ private:
 	required_region_ptr<u8> m_chargen;
 
 	bool m_dmatype;
+	bool m_keyin;
 };
 
 void z29_state::machine_start()
 {
 	save_item(NAME(m_dmatype));
+	save_item(NAME(m_keyin));
+}
+
+WRITE_LINE_MEMBER(z29_state::keyin_w)
+{
+	m_keyin = state;
+}
+
+u8 z29_state::p1_r()
+{
+	return m_keyin ? 0xfd : 0xff;
 }
 
 void z29_state::p3_w(u8 data)
@@ -63,7 +81,7 @@ void z29_state::p3_w(u8 data)
 	m_dmatype = BIT(data, 4);
 }
 
-READ8_MEMBER(z29_state::bs_24k_r)
+u8 z29_state::bs_24k_r(offs_t offset)
 {
 	if (!machine().side_effects_disabled())
 	{
@@ -122,11 +140,16 @@ void z29_state::z29(machine_config &config)
 	I8031(config, m_maincpu, 14.784_MHz_XTAL / 2); // Intel P8031AH
 	m_maincpu->set_addrmap(AS_PROGRAM, &z29_state::prg_map);
 	m_maincpu->set_addrmap(AS_IO, &z29_state::ext_map);
-	m_maincpu->port_in_cb<1>().set_constant(0xfd); // hack around keyboard not working
+	m_maincpu->port_in_cb<1>().set(FUNC(z29_state::p1_r));
+	m_maincpu->port_out_cb<1>().set(m_keyboard, FUNC(z29_keyboard_port_device::keyout_w)).bit(0).invert();
 	m_maincpu->port_out_cb<3>().set(FUNC(z29_state::p3_w));
 
 	X2210(config, m_nvram);
 
+	Z29_KEYBOARD(config, m_keyboard, z29_keyboards, /*"heath"*/ "md");
+	m_keyboard->keyin_callback().set(FUNC(z29_state::keyin_w));
+	m_keyboard->reset_callback().set_inputline(m_maincpu, INPUT_LINE_RESET).invert();
+
 	screen_device &screen(SCREEN(config, "screen", SCREEN_TYPE_RASTER));
 	screen.set_raw(14.784_MHz_XTAL, 880, 0, 640, 280, 0, 250);
 	screen.set_screen_update("crtc1", FUNC(i8276_device::screen_update));
@@ -136,8 +159,6 @@ void z29_state::z29(machine_config &config)
 	m_crtc[0]->irq_wr_callback().set_inputline(m_maincpu, MCS51_INT1_LINE);
 
 	I8276(config, m_crtc[1], 14.784_MHz_XTAL / 8).set_character_width(8);
-
-	I8021(config, "kbdmcu", 3.579545_MHz_XTAL).set_disable();
 }
 
 
@@ -148,9 +169,6 @@ ROM_START(z29) // All EPROMs on 85-2835-1 terminal board are HN482732AG-30
 
 	ROM_REGION(0x1000, "chargen", 0)
 	ROM_LOAD("u429.bin", 0x0000, 0x1000, CRC(5e3bc5bf) SHA1(18d73e3d74a9768bee8b063ea45891f955558ae7))
-
-	ROM_REGION(0x400, "kbdmcu", 0)
-	ROM_LOAD("444-100.bin", 0x000, 0x400, NO_DUMP)
 ROM_END
 
 
diff --git a/src/mame/mame.lst b/src/mame/mame.lst
index 89dc8475b88..76cb5890925 100644
--- a/src/mame/mame.lst
+++ b/src/mame/mame.lst
@@ -21873,7 +21873,6 @@ fl100                           // (c) 198? Grundig
 
 @source:mdt60.cpp
 mdt60                           //
-z22                             //
 
 @source:meadows.cpp
 bowl3d                          // [1978?]
@@ -41792,6 +41791,9 @@ z1013k69                        //
 z1013k76                        //
 z1013s60                        //
 
+@source:z22.cpp
+z22                             //
+
 @source:z29.cpp
 z29                             //
 
diff --git a/src/mame/mess.flt b/src/mame/mess.flt
index 147370eecfa..299c05b17c8 100644
--- a/src/mame/mess.flt
+++ b/src/mame/mess.flt
@@ -1075,6 +1075,7 @@ ymtx81z.cpp
 ymvl70.cpp
 z100.cpp
 z1013.cpp
+z22.cpp
 z29.cpp
 z80dev.cpp
 z80ne.cpp