diff --git a/scripts/src/bus.lua b/scripts/src/bus.lua
index 0587a63ad1d..4196c80050b 100644
--- a/scripts/src/bus.lua
+++ b/scripts/src/bus.lua
@@ -201,6 +201,8 @@ if (BUSES["ADB"]~=null) then
 		MAME_DIR .. "src/devices/bus/adb/adb.h",
 		MAME_DIR .. "src/devices/bus/adb/adbhle.cpp",
 		MAME_DIR .. "src/devices/bus/adb/adbhle.h",
+		MAME_DIR .. "src/devices/bus/adb/a9m0330.cpp",
+		MAME_DIR .. "src/devices/bus/adb/a9m0330.h",
 		MAME_DIR .. "src/devices/bus/adb/a9m0331.cpp",
 		MAME_DIR .. "src/devices/bus/adb/a9m0331.h",
 	}
diff --git a/src/devices/bus/adb/a9m0330.cpp b/src/devices/bus/adb/a9m0330.cpp
new file mode 100644
index 00000000000..c4d8db34b4e
--- /dev/null
+++ b/src/devices/bus/adb/a9m0330.cpp
@@ -0,0 +1,266 @@
+// license:BSD-3-Clause
+// copyright-holders: R. Belmont
+/*********************************************************************
+
+    a9m0330.cpp
+    Apple model A9M0330 ADB keyboard for the Apple IIgs
+    by R. Belmont, with hints from pluskbd.cpp by Vas Crabb
+
+    Port 1: Row selects 0-7
+    Port 2: Bit 0: row select bit 8
+            Bit 1: row select bit 9
+            Bit 2: Shift
+            Bit 3: Caps Lock
+            Bit 4: Option
+            Bit 5: Command
+            Bit 6: Reset/Power? Control?
+            Bit 7: ADB out
+    Bus: Matrix read input
+    T1: ADB in
+
+*********************************************************************/
+
+#include "emu.h"
+#include "a9m0330.h"
+
+DEFINE_DEVICE_TYPE(ADB_A9M0330, a9m0330_device, "a9m0330", "Apple IIgs ADB Keyboard (A9M0330)");
+
+ROM_START(a9m0330)
+	ROM_REGION(0x400, "mcu", 0)
+	// early 1986 version
+	ROM_LOAD("341-0232a.bin", 0x000000, 0x000400, CRC(6a158b9f) SHA1(e8744180075182849d431fd8023a52a062a6da76))
+	// later 1987 version
+	ROM_LOAD("341-0124a.bin", 0x000000, 0x000400, CRC(2a3576bf) SHA1(58fbf770d3801a02d0944039829f9241b5279013))
+ROM_END
+
+// matrix is believed to be the same as the Mac Plus keyboard at the moment
+static INPUT_PORTS_START(a9m0330)
+	PORT_START("ROW0")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_ASTERISK)   PORT_CHAR(UCHAR_MAMEKEY(ASTERISK))   PORT_NAME("Keypad *")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_8_PAD)      PORT_CHAR(UCHAR_MAMEKEY(8_PAD))      PORT_NAME("Keypad 8")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_P)          PORT_CHAR('p')   PORT_CHAR('P')
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_D)          PORT_CHAR('d')   PORT_CHAR('D')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_W)          PORT_CHAR('w')   PORT_CHAR('W')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_2)          PORT_CHAR('2')   PORT_CHAR('@')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_V)          PORT_CHAR('v')   PORT_CHAR('V')
+
+	PORT_START("ROW1")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSLASH)  PORT_CHAR('\\')  PORT_CHAR('|')
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_SLASH_PAD)  PORT_CHAR(UCHAR_MAMEKEY(SLASH_PAD))  PORT_NAME("Keypad /")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_9_PAD)      PORT_CHAR(UCHAR_MAMEKEY(9_PAD))      PORT_NAME("Keypad 9")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_OPENBRACE)  PORT_CHAR('[')   PORT_CHAR('{')
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_F)          PORT_CHAR('f')   PORT_CHAR('F')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_E)          PORT_CHAR('e')   PORT_CHAR('E')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_3)          PORT_CHAR('3')   PORT_CHAR('#')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_B)          PORT_CHAR('b')   PORT_CHAR('B')
+
+	PORT_START("ROW2")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_LEFT)       PORT_CHAR(UCHAR_MAMEKEY(LEFT))
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_EQUALS_PAD) PORT_CHAR(UCHAR_MAMEKEY(EQUALS_PAD)) PORT_NAME("Keypad =")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS_PAD)  PORT_CHAR(UCHAR_MAMEKEY(MINUS_PAD))  PORT_NAME("Keypad -")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_CLOSEBRACE) PORT_CHAR(']')   PORT_CHAR('}')
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_G)          PORT_CHAR('g')   PORT_CHAR('G')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_R)          PORT_CHAR('r')   PORT_CHAR('R')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_4)          PORT_CHAR('4')   PORT_CHAR('$')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_N)          PORT_CHAR('n')   PORT_CHAR('N')
+
+	PORT_START("ROW3")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_RIGHT)      PORT_CHAR(UCHAR_MAMEKEY(RIGHT))
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_NUMLOCK)    PORT_CHAR(UCHAR_MAMEKEY(NUMLOCK))    PORT_NAME("Keypad Clear")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_UP)         PORT_CHAR(UCHAR_MAMEKEY(UP))
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_QUOTE)      PORT_CHAR('\'')  PORT_CHAR('"')
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_H)          PORT_CHAR('h')   PORT_CHAR('H')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_T)          PORT_CHAR('t')   PORT_CHAR('T')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_5)          PORT_CHAR('5')   PORT_CHAR('%')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_M)          PORT_CHAR('m')   PORT_CHAR('M')
+
+	PORT_START("ROW4")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_DOWN)       PORT_CHAR(UCHAR_MAMEKEY(DOWN))
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_BACKSPACE)  PORT_CHAR(0x08)                      PORT_NAME("Backspace")
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_1_PAD)      PORT_CHAR(UCHAR_MAMEKEY(1_PAD))      PORT_NAME("Keypad 1")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER)      PORT_CHAR(0x0d)                      PORT_NAME("Return")
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_J)          PORT_CHAR('j')   PORT_CHAR('J')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_Y)          PORT_CHAR('y')   PORT_CHAR('Y')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_6)          PORT_CHAR('6')   PORT_CHAR('^')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_COMMA)      PORT_CHAR(',')   PORT_CHAR('<')
+
+	PORT_START("ROW5")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_0_PAD)      PORT_CHAR(UCHAR_MAMEKEY(0_PAD))      PORT_NAME("Keypad 0")
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_EQUALS)     PORT_CHAR('=')   PORT_CHAR('+')
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_2_PAD)      PORT_CHAR(UCHAR_MAMEKEY(2_PAD))      PORT_NAME("Keypad 2")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_4_PAD)      PORT_CHAR(UCHAR_MAMEKEY(4_PAD))      PORT_NAME("Keypad 4")
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_K)          PORT_CHAR('k')   PORT_CHAR('K')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_U)          PORT_CHAR('u')   PORT_CHAR('U')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_7)          PORT_CHAR('7')   PORT_CHAR('&')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_STOP)       PORT_CHAR('.')   PORT_CHAR('>')
+
+	PORT_START("ROW6")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_DEL_PAD)    PORT_CHAR(UCHAR_MAMEKEY(DEL_PAD))    PORT_NAME("Keypad .")
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_MINUS)      PORT_CHAR('-')   PORT_CHAR('_')
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_3_PAD)      PORT_CHAR(UCHAR_MAMEKEY(3_PAD))      PORT_NAME("Keypad 3")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_5_PAD)      PORT_CHAR(UCHAR_MAMEKEY(5_PAD))      PORT_NAME("Keypad 5")
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_L)          PORT_CHAR('l')   PORT_CHAR('L')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_I)          PORT_CHAR('i')   PORT_CHAR('I')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_8)          PORT_CHAR('8')   PORT_CHAR('*')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_SLASH)      PORT_CHAR('/')   PORT_CHAR('?')
+
+	PORT_START("ROW7")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_ENTER_PAD)  PORT_CHAR(UCHAR_MAMEKEY(ENTER_PAD))  PORT_NAME("Keypad Enter")
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_0)          PORT_CHAR('0')   PORT_CHAR(')')
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_PLUS_PAD)   PORT_CHAR(UCHAR_MAMEKEY(PLUS_PAD))   PORT_NAME("Keypad +")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_6_PAD)      PORT_CHAR(UCHAR_MAMEKEY(6_PAD))      PORT_NAME("Keypad 6")
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_COLON)      PORT_CHAR(';')   PORT_CHAR(':')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_O)          PORT_CHAR('o')   PORT_CHAR('O')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_9)          PORT_CHAR('9')   PORT_CHAR('(')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_UNUSED)
+
+	PORT_START("ROW8")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_Z)          PORT_CHAR('z')   PORT_CHAR('Z')
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_SPACE)      PORT_CHAR(' ')
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_A)          PORT_CHAR('a')   PORT_CHAR('A')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_TAB)        PORT_CHAR(0x09)                      PORT_NAME("Tab")
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_TILDE)      PORT_CHAR('`')   PORT_CHAR('~')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_X)          PORT_CHAR('x')   PORT_CHAR('X')
+
+	PORT_START("ROW9")
+	PORT_BIT(0x03, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_7_PAD)      PORT_CHAR(UCHAR_MAMEKEY(7_PAD))      PORT_NAME("Keypad 7")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_S)          PORT_CHAR('s')   PORT_CHAR('S')
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_Q)          PORT_CHAR('q')   PORT_CHAR('Q')
+	PORT_BIT(0x40, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_1)          PORT_CHAR('1')   PORT_CHAR('!')
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_C)          PORT_CHAR('c')   PORT_CHAR('C')
+
+	PORT_START("P2")
+	PORT_BIT(0x43, IP_ACTIVE_LOW, IPT_UNUSED)
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_LSHIFT) PORT_CODE(KEYCODE_RSHIFT) PORT_CHAR(UCHAR_SHIFT_1)           PORT_NAME("Shift")
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_CAPSLOCK)                         PORT_CHAR(UCHAR_MAMEKEY(CAPSLOCK)) PORT_NAME("Caps Lock") PORT_TOGGLE
+	PORT_BIT(0x10, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_LALT)   PORT_CODE(KEYCODE_RALT)   PORT_CHAR(UCHAR_SHIFT_2)           PORT_NAME("Option")
+	PORT_BIT(0x20, IP_ACTIVE_LOW, IPT_KEYBOARD) PORT_CODE(KEYCODE_LCONTROL)                                                            PORT_NAME("Command")
+	PORT_BIT(0x80, IP_ACTIVE_LOW, IPT_UNUSED)
+INPUT_PORTS_END
+
+/***************************************************************************
+    DEVICE CONFIGURATION
+***************************************************************************/
+
+/*-------------------------------------------------
+    input_ports - device-specific input ports
+-------------------------------------------------*/
+ioport_constructor a9m0330_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME(a9m0330);
+}
+
+/*-------------------------------------------------
+    device_add_mconfig - device-specific
+    machine configurations
+-------------------------------------------------*/
+void a9m0330_device::device_add_mconfig(machine_config &config)
+{
+	I8048(config, m_mcu, 6_MHz_XTAL);
+	m_mcu->set_addrmap(AS_PROGRAM, &a9m0330_device::program_map);
+	m_mcu->bus_in_cb().set(FUNC(a9m0330_device::bus_r));
+	m_mcu->p1_out_cb().set(FUNC(a9m0330_device::p1_w));
+	m_mcu->p2_in_cb().set_ioport("P2");
+	m_mcu->p2_out_cb().set(FUNC(a9m0330_device::p2_w));
+	m_mcu->t0_in_cb().set(FUNC(a9m0330_device::t0_r));
+	m_mcu->t1_in_cb().set(FUNC(a9m0330_device::t1_r));
+}
+
+/*-------------------------------------------------
+    rom_region - device-specific ROM region
+-------------------------------------------------*/
+const tiny_rom_entry *a9m0330_device::device_rom_region() const
+{
+	return ROM_NAME(a9m0330);
+}
+
+/***************************************************************************
+    DEVICE IMPLEMENTATION
+***************************************************************************/
+
+a9m0330_device::a9m0330_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) :
+	adb_device(mconfig, ADB_A9M0330, tag, owner, clock),
+	adb_slot_card_interface(mconfig, *this, DEVICE_SELF)
+	, m_mcu(*this, "mcu")
+	, m_rows{ *this, "ROW%u", 0U }
+{
+}
+
+void a9m0330_device::device_start()
+{
+	adb_device::device_start();
+
+	save_item(NAME(m_adb_state));
+	save_item(NAME(m_kbd_row));
+	save_item(NAME(m_our_last_adb_state));
+}
+
+void a9m0330_device::device_reset()
+{
+	adb_device::device_reset();
+
+	m_our_last_adb_state = 1;
+	m_adb_state = 1;
+	m_kbd_row = 0x3ff;
+}
+
+void a9m0330_device::adb_w(int state)
+{
+	m_adb_state = state;
+}
+
+void a9m0330_device::program_map(address_map &map)
+{
+	map(0x0000, 0x03ff).rom().region("mcu", 0);
+}
+
+u8 a9m0330_device::bus_r()
+{
+	u8 result = 0xffU;
+
+	for (unsigned int i = 0U; m_rows.size() > i; i++)
+	{
+		if (!BIT(m_kbd_row, i))
+		{
+			result &= m_rows[i]->read();
+		}
+	}
+
+	return result;
+}
+
+void a9m0330_device::p1_w(u8 data)
+{
+	m_kbd_row &= 0x300;
+	m_kbd_row |= data;
+}
+
+void a9m0330_device::p2_w(u8 data)
+{
+	m_kbd_row &= 0xff;
+	m_kbd_row |= (data & 0x03) << 8;
+
+	// ADB drive is through an inverting transistor
+	int adb_state = (data>>7) ^ 1;
+	if (adb_state != m_our_last_adb_state)
+	{
+		m_adb_cb(adb_state);
+		m_our_last_adb_state = adb_state;
+	}
+}
+
+DECLARE_READ_LINE_MEMBER(a9m0330_device::t0_r)
+{
+	// appears to be a config jumper of some sort
+	return 0;
+}
+
+DECLARE_READ_LINE_MEMBER(a9m0330_device::t1_r)
+{
+	return m_adb_state & 1;
+}
diff --git a/src/devices/bus/adb/a9m0330.h b/src/devices/bus/adb/a9m0330.h
new file mode 100644
index 00000000000..1d44a28bba8
--- /dev/null
+++ b/src/devices/bus/adb/a9m0330.h
@@ -0,0 +1,48 @@
+// license:BSD-3-Clause
+// copyright-holders: R. Belmont
+
+// a9m0330.h - Apple IIgs ADB keyboard
+
+#ifndef MAME_BUS_ADB_A9M0330_H
+#define MAME_BUS_ADB_A9M0330_H
+
+#pragma once
+
+#include "adb.h"
+#include "cpu/mcs48/mcs48.h"
+
+class a9m0330_device : public adb_device, public adb_slot_card_interface
+{
+public:
+	a9m0330_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock);
+
+protected:
+	virtual void device_start() override;
+	virtual void device_reset() override;
+
+	virtual const tiny_rom_entry *device_rom_region() const override;
+	virtual ioport_constructor device_input_ports() const override;
+	virtual void device_add_mconfig(machine_config &config) override;
+
+	virtual void adb_w(int state) override;
+
+	required_device<i8048_device> m_mcu;
+	required_ioport_array<10> m_rows;
+
+	void program_map(address_map &map);
+
+private:
+	u8 bus_r();
+	void p1_w(u8 data);
+	void p2_w(u8 data);
+	DECLARE_READ_LINE_MEMBER(t0_r);
+	DECLARE_READ_LINE_MEMBER(t1_r);
+
+	int m_adb_state;
+	int m_kbd_row;
+	int m_our_last_adb_state;
+};
+
+DECLARE_DEVICE_TYPE(ADB_A9M0330, a9m0330_device)
+
+#endif
diff --git a/src/devices/bus/adb/a9m0331.cpp b/src/devices/bus/adb/a9m0331.cpp
index 73c4240d414..f0178dc4386 100644
--- a/src/devices/bus/adb/a9m0331.cpp
+++ b/src/devices/bus/adb/a9m0331.cpp
@@ -109,17 +109,17 @@ void a9m0331_device::mcu_port_c_w(u8 data)
 	logerror("%02x to port C\n", data);
 }
 
-u8 mcu_port_a_r()
+u8 a9m0331_device::mcu_port_a_r()
 {
 	return 0xff;
 }
 
-u8 mcu_port_b_r()
+u8 a9m0331_device::mcu_port_b_r()
 {
 	return 0xff;
 }
 
-u8 mcu_port_c_r()
+u8 a9m0331_device::mcu_port_c_r()
 {
 	return 0xff;
 }
diff --git a/src/devices/bus/adb/adb.cpp b/src/devices/bus/adb/adb.cpp
index d0d329fd741..cdf0810369a 100644
--- a/src/devices/bus/adb/adb.cpp
+++ b/src/devices/bus/adb/adb.cpp
@@ -11,6 +11,7 @@
 #include "adb.h"
 
 #include "adbhle.h"
+#include "a9m0330.h"
 #include "a9m0331.h"
 
 DEFINE_DEVICE_TYPE(ADB_CONNECTOR, adb_connector, "adbslot", "ADB connector")
@@ -51,6 +52,8 @@ adb_device::adb_device(const machine_config &mconfig, device_type type, const ch
 
 void adb_device::device_start()
 {
+	m_adb_cb.resolve_safe();
+	m_poweron_cb.resolve_safe();
 }
 
 void adb_device::device_reset()
@@ -62,5 +65,6 @@ void adb_device::device_reset()
 void adb_device::default_devices(device_slot_interface &device)
 {
 	device.option_add("hle", ADB_HLE);
+	device.option_add("a9m0330", ADB_A9M0330);
 	device.option_add("a9m0331", ADB_A9M0331);
 }
diff --git a/src/devices/bus/adb/adb.h b/src/devices/bus/adb/adb.h
index 8a07986c531..e6b15e8f61d 100644
--- a/src/devices/bus/adb/adb.h
+++ b/src/devices/bus/adb/adb.h
@@ -62,8 +62,9 @@ protected:
 	virtual void device_start() override;
 	virtual void device_reset() override;
 
-private:
 	devcb_write_line m_adb_cb;
+
+private:
 	devcb_write_line m_poweron_cb;
 	bool m_adb_istate, m_adb_ostate;
 };
diff --git a/src/mame/machine/egret.cpp b/src/mame/machine/egret.cpp
index ecd7146251b..e9276c05352 100644
--- a/src/mame/machine/egret.cpp
+++ b/src/mame/machine/egret.cpp
@@ -89,7 +89,7 @@ void egret_device::device_add_mconfig(machine_config &config)
 	m_maincpu->set_addrmap(AS_PROGRAM, &egret_device::egret_map);
 
 	#if USE_BUS_ADB
-	ADB_CONNECTOR(config, "adb1", adb_device::default_devices, "a9m0331", false);
+	ADB_CONNECTOR(config, "adb1", adb_device::default_devices, "a9m0330", false);
 	#endif
 }
 
@@ -371,7 +371,7 @@ egret_device::egret_device(const machine_config &mconfig, const char *tag, devic
 	  write_via_data(*this),
 	  m_maincpu(*this, EGRET_CPU_TAG)
 #if USE_BUS_ADB
-	, m_adb_connector{{*this, ":adb1"}, {*this, finder_base::DUMMY_TAG}}
+	, m_adb_connector{{*this, "adb1"}, {*this, finder_base::DUMMY_TAG}}
 #endif
 {
 }