diff --git a/scripts/src/bus.lua b/scripts/src/bus.lua
index 0d98c3da1f7..bebcde91fae 100644
--- a/scripts/src/bus.lua
+++ b/scripts/src/bus.lua
@@ -3306,6 +3306,8 @@ if (BUSES["EINSTEIN_USERPORT"]~=null) then
 	files {
 		MAME_DIR .. "src/devices/bus/einstein/userport/userport.cpp",
 		MAME_DIR .. "src/devices/bus/einstein/userport/userport.h",
+		MAME_DIR .. "src/devices/bus/einstein/userport/mouse.cpp",
+		MAME_DIR .. "src/devices/bus/einstein/userport/mouse.h",
 		MAME_DIR .. "src/devices/bus/einstein/userport/speech.cpp",
 		MAME_DIR .. "src/devices/bus/einstein/userport/speech.h",
 	}
diff --git a/src/devices/bus/einstein/userport/mouse.cpp b/src/devices/bus/einstein/userport/mouse.cpp
new file mode 100644
index 00000000000..945bff5d37c
--- /dev/null
+++ b/src/devices/bus/einstein/userport/mouse.cpp
@@ -0,0 +1,106 @@
+// license: GPL-2.0+
+// copyright-holders: Dirk Best
+/***************************************************************************
+
+    Einstein Mouse
+
+    TODO: Verify implementation (mouse directions are digital only?)
+
+***************************************************************************/
+
+#include "emu.h"
+#include "mouse.h"
+
+
+//**************************************************************************
+//  DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(EINSTEIN_MOUSE, einstein_mouse_device, "einstein_mouse", "Einstein Mouse")
+
+//-------------------------------------------------
+//  input_ports - device-specific input ports
+//-------------------------------------------------
+
+static INPUT_PORTS_START( mouse )
+	PORT_START("mouse_b")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_BUTTON1) PORT_PLAYER(1) PORT_NAME("Mouse Left Button")
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_BUTTON2) PORT_PLAYER(1) PORT_NAME("Mouse Right Button")
+
+	PORT_START("mouse_x")
+	PORT_BIT(0xff, 0x00, IPT_MOUSE_X) PORT_PLAYER(1) PORT_SENSITIVITY(100) PORT_KEYDELTA(5)
+
+	PORT_START("mouse_y")
+	PORT_BIT(0xff, 0x00, IPT_MOUSE_Y) PORT_PLAYER(1) PORT_SENSITIVITY(100) PORT_KEYDELTA(5)
+INPUT_PORTS_END
+
+ioport_constructor einstein_mouse_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME( mouse );
+}
+
+
+//**************************************************************************
+//  LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+//  einstein_speech_device - constructor
+//-------------------------------------------------
+
+einstein_mouse_device::einstein_mouse_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+	device_t(mconfig, EINSTEIN_MOUSE, tag, owner, clock),
+	device_einstein_userport_interface(mconfig, *this),
+	m_mouse_b(*this, "mouse_b"),
+	m_mouse_x(*this, "mouse_x"),
+	m_mouse_y(*this, "mouse_y"),
+	m_x(0), m_y(0)
+{
+}
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void einstein_mouse_device::device_start()
+{
+	// register for save states
+	save_item(NAME(m_x));
+	save_item(NAME(m_y));
+}
+
+
+//**************************************************************************
+//  IMPLEMENTATION
+//**************************************************************************
+
+// 7-------  not used
+// -6------  not used
+// --5-----  right button
+// ---4----  left button
+// ----3---  right
+// -----2--  left
+// ------1-  down
+// -------0  up
+
+uint8_t einstein_mouse_device::read()
+{
+	uint8_t data = 0;
+
+	uint8_t x = m_mouse_x->read();
+	uint8_t y = m_mouse_y->read();
+
+	int dx = m_x - x;
+	int dy = m_y - y;
+
+	data |= m_mouse_b->read() << 4;
+	data |= (dx < 0) ? 0 : 1 << 3;
+	data |= (dx > 0) ? 0 : 1 << 2;
+	data |= (dy < 0) ? 0 : 1 << 1;
+	data |= (dy > 0) ? 0 : 1 << 0;
+
+	m_x = x;
+	m_y = y;
+
+	return data;
+}
diff --git a/src/devices/bus/einstein/userport/mouse.h b/src/devices/bus/einstein/userport/mouse.h
new file mode 100644
index 00000000000..dad8200d06b
--- /dev/null
+++ b/src/devices/bus/einstein/userport/mouse.h
@@ -0,0 +1,47 @@
+// license: GPL-2.0+
+// copyright-holders: Dirk Best
+/***************************************************************************
+
+    Einstein Mouse
+
+***************************************************************************/
+
+#ifndef MAME_BUS_EINSTEIN_USERPORT_MOUSE_H
+#define MAME_BUS_EINSTEIN_USERPORT_MOUSE_H
+
+#pragma once
+
+#include "userport.h"
+
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+// ======================> einstein_mouse_device
+
+class einstein_mouse_device : public device_t, public device_einstein_userport_interface
+{
+public:
+	// construction/destruction
+	einstein_mouse_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+protected:
+	virtual ioport_constructor device_input_ports() const override;
+	virtual void device_start() override;
+
+	virtual uint8_t read() override;
+
+private:
+	required_ioport m_mouse_b;
+	required_ioport m_mouse_x;
+	required_ioport m_mouse_y;
+
+	int m_x;
+	int m_y;
+};
+
+// device type definition
+DECLARE_DEVICE_TYPE(EINSTEIN_MOUSE, einstein_mouse_device)
+
+#endif // MAME_BUS_EINSTEIN_USERPORT_MOUSE_H
diff --git a/src/devices/bus/einstein/userport/userport.cpp b/src/devices/bus/einstein/userport/userport.cpp
index 853fbd8777a..d38dba12af9 100644
--- a/src/devices/bus/einstein/userport/userport.cpp
+++ b/src/devices/bus/einstein/userport/userport.cpp
@@ -10,6 +10,7 @@
 #include "userport.h"
 
 // supported devices
+#include "mouse.h"
 #include "speech.h"
 
 
@@ -118,5 +119,6 @@ device_einstein_userport_interface::~device_einstein_userport_interface()
 //**************************************************************************
 
 SLOT_INTERFACE_START( einstein_userport_cards )
+	SLOT_INTERFACE("mouse", EINSTEIN_MOUSE)
 	SLOT_INTERFACE("speech", EINSTEIN_SPEECH)
 SLOT_INTERFACE_END