Index: b/src/mame/machine/vectrex.c
===================================================================
--- a/src/mame/machine/vectrex.c	2012-04-28 15:58:31.000000000 -0400
+++ b/src/mame/machine/vectrex.c	2012-04-28 16:03:46.000000000 -0400
@@ -71,6 +71,11 @@
 	if (image.software_entry() == NULL)
 	{
 		image.fread( mem, 0x8000);
+		if (image.length() > 0x8000)
+		{
+			image.fread( mem+0x10000, 0x8000);
+			state->m_64k_cart = 1;
+		}
 	} else {
 		int size = image.get_software_region_length("rom");
 		memcpy(mem, image.get_software_region("rom"), size);
@@ -352,6 +357,7 @@
 	vectrex_state *state = machine.driver_data<vectrex_state>();
 	int i;
 
+	state->m_64k_cart = 0;
 	state->m_imager_angles = unknown_game_angles;
 	state->m_beam_color = RGB_WHITE;
 	for (i=0; i<ARRAY_LENGTH(state->m_imager_colors); i++)
Index: b/src/mame/includes/vectrex.h
===================================================================
--- a/src/mame/includes/vectrex.h	2012-04-28 15:58:31.000000000 -0400
+++ b/src/mame/includes/vectrex.h	2012-04-28 15:59:53.000000000 -0400
@@ -26,6 +26,7 @@
 		m_gce_vectorram(*this, "gce_vectorram"){ }
 
 	required_shared_ptr<UINT8> m_gce_vectorram;
+	int m_64k_cart;
 	int m_imager_status;
 	UINT32 m_beam_color;
 	unsigned char m_via_out[2];
Index: b/src/mame/video/vectrex.c
===================================================================
--- a/src/mame/video/vectrex.c	2012-04-28 15:58:31.000000000 -0400
+++ b/src/mame/video/vectrex.c	2012-04-28 15:59:53.000000000 -0400
@@ -386,6 +386,14 @@
 		}
 	}
 
+	/* Cartridge bank-switching */
+	if (state->m_64k_cart && ((data ^ state->m_via_out[PORTB]) & 0x40))
+	{
+		device_t &root_device = device->machine().root_device();
+
+		root_device.membank("bank1")->set_base(root_device.memregion("maincpu")->base() + ((data & 0x40) ? 0x10000 : 0x0000));
+	}
+
 	/* Sound */
 	if (data & 0x10)
 	{
Index: b/src/mame/drivers/vectrex.c
===================================================================
--- a/src/mame/drivers/vectrex.c	2012-04-28 15:58:31.000000000 -0400
+++ b/src/mame/drivers/vectrex.c	2012-04-28 16:03:46.000000000 -0400
@@ -20,7 +20,7 @@
 
 
 static ADDRESS_MAP_START(vectrex_map, AS_PROGRAM, 8, vectrex_state )
-	AM_RANGE(0x0000, 0x7fff) AM_ROM
+	AM_RANGE(0x0000, 0x7fff) AM_ROMBANK("bank1") AM_REGION("maincpu", 0)
 	AM_RANGE(0xc800, 0xcbff) AM_RAM AM_MIRROR(0x0400) AM_SHARE("gce_vectorram")
 	AM_RANGE(0xd000, 0xd7ff) AM_READWRITE(vectrex_via_r, vectrex_via_w)
 	AM_RANGE(0xe000, 0xffff) AM_ROM
@@ -133,7 +133,7 @@
 MACHINE_CONFIG_END
 
 ROM_START(vectrex)
-	ROM_REGION(0x10000,"maincpu", 0)
+	ROM_REGION(0x18000,"maincpu", 0)
 	ROM_LOAD("system.img", 0xe000, 0x2000, CRC(ba13fb57) SHA1(65d07426b520ddd3115d40f255511e0fd2e20ae7))
 ROM_END