diff --git a/src/mame/drivers/laserbat.c b/src/mame/drivers/laserbat.c
index 992edf5ba16..8b051288f9d 100644
--- a/src/mame/drivers/laserbat.c
+++ b/src/mame/drivers/laserbat.c
@@ -29,7 +29,6 @@ TODO:
 
 WRITE8_MEMBER(laserbat_state::laserbat_videoram_w)
 {
-
 	if (m_video_page == 0)
 	{
 		m_videoram[offset] = data;
@@ -44,7 +43,6 @@ WRITE8_MEMBER(laserbat_state::laserbat_videoram_w)
 
 WRITE8_MEMBER(laserbat_state::video_extra_w)
 {
-
 	m_video_page = (data & 0x10) >> 4;
 	m_sprite_enable = (data & 1) ^ 1;
 	m_sprite_code = (data & 0xe0) >> 5;
@@ -53,7 +51,6 @@ WRITE8_MEMBER(laserbat_state::video_extra_w)
 
 WRITE8_MEMBER(laserbat_state::sprite_x_y_w)
 {
-
 	if (offset == 0)
 		m_sprite_x = 256 - data;
 	else
@@ -62,7 +59,6 @@ WRITE8_MEMBER(laserbat_state::sprite_x_y_w)
 
 WRITE8_MEMBER(laserbat_state::laserbat_input_mux_w)
 {
-
 	m_input_mux = (data & 0x30) >> 4;
 
 	flip_screen_set_no_update(data & 0x08);
@@ -185,6 +181,7 @@ static ADDRESS_MAP_START( laserbat_io_map, AS_IO, 8, laserbat_state )
 	AM_RANGE(0x06, 0x06) AM_WRITE(laserbat_input_mux_w)
 	AM_RANGE(0x07, 0x07) AM_WRITE(laserbat_csound2_w)
 	AM_RANGE(S2650_SENSE_PORT, S2650_SENSE_PORT) AM_READ_PORT("SENSE")
+	AM_RANGE(S2650_FO_PORT, S2650_FO_PORT) AM_RAM AM_SHARE("fo_state")
 ADDRESS_MAP_END
 
 
@@ -197,6 +194,7 @@ static ADDRESS_MAP_START( catnmous_io_map, AS_IO, 8, laserbat_state )
 	AM_RANGE(0x06, 0x06) AM_WRITE(laserbat_input_mux_w)
 	AM_RANGE(0x07, 0x07) AM_WRITENOP // unknown
 	AM_RANGE(S2650_SENSE_PORT, S2650_SENSE_PORT) AM_READ_PORT("SENSE")
+	AM_RANGE(S2650_FO_PORT, S2650_FO_PORT) AM_RAM AM_SHARE("fo_state")
 ADDRESS_MAP_END
 
 // the same as in zaccaria.c ?
@@ -256,10 +254,10 @@ static INPUT_PORTS_START( laserbat )
 	PORT_DIPSETTING(    0x10, "3" )
 	PORT_DIPSETTING(    0x20, "5" )
 	PORT_DIPSETTING(    0x30, "6" )
-	PORT_DIPSETTING(    0x40, "Infinites" )
-//  PORT_DIPSETTING(    0x50, "Infinites" )
-//  PORT_DIPSETTING(    0x60, "Infinites" )
-//  PORT_DIPSETTING(    0x70, "Infinites" )
+	PORT_DIPSETTING(    0x40, "Infinite" )
+//  PORT_DIPSETTING(    0x50, "Infinite" )
+//  PORT_DIPSETTING(    0x60, "Infinite" )
+//  PORT_DIPSETTING(    0x70, "Infinite" )
 	PORT_DIPNAME( 0x80, 0x80, "Collision Detection" )
 	PORT_DIPSETTING(    0x00, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x80, DEF_STR( On ) )
@@ -409,10 +407,10 @@ static INPUT_PORTS_START( catnmous )
 	PORT_DIPSETTING(    0x10, "3" )
 	PORT_DIPSETTING(    0x20, "4" )
 	PORT_DIPSETTING(    0x30, "5" )
-	PORT_DIPSETTING(    0x40, "Infinites" )
-//  PORT_DIPSETTING(    0x50, "Infinites" )
-//  PORT_DIPSETTING(    0x60, "Infinites" )
-//  PORT_DIPSETTING(    0x70, "Infinites" )
+	PORT_DIPSETTING(    0x40, "Infinite" )
+//  PORT_DIPSETTING(    0x50, "Infinite" )
+//  PORT_DIPSETTING(    0x60, "Infinite" )
+//  PORT_DIPSETTING(    0x70, "Infinite" )
 	PORT_DIPNAME( 0x80, 0x80, "Game Over Melody" )
 	PORT_DIPSETTING(    0x00, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x80, DEF_STR( On ) )
@@ -698,7 +696,6 @@ static MACHINE_START( laserbat )
 {
 	laserbat_state *state = machine.driver_data<laserbat_state>();
 
-	state->m_audiocpu = machine.device("audiocpu");
 	state->m_s2636_1 = machine.device("s2636_1");
 	state->m_s2636_2 = machine.device("s2636_2");
 	state->m_s2636_3 = machine.device("s2636_3");
diff --git a/src/mame/includes/laserbat.h b/src/mame/includes/laserbat.h
index ab1fc02733a..82b6e8026f8 100644
--- a/src/mame/includes/laserbat.h
+++ b/src/mame/includes/laserbat.h
@@ -10,7 +10,15 @@ class laserbat_state : public driver_device
 {
 public:
 	laserbat_state(const machine_config &mconfig, device_type type, const char *tag)
-		: driver_device(mconfig, type, tag) { }
+		: driver_device(mconfig, type, tag),
+		m_maincpu(*this, "maincpu"),
+		m_audiocpu(*this, "audiocpu"),
+		m_fo_state(*this, "fo_state")
+	{ }
+
+	required_device<cpu_device> m_maincpu;
+	optional_device<cpu_device> m_audiocpu;
+	required_shared_ptr<UINT8> m_fo_state;
 
 	/* video-related */
 	tilemap_t    *m_bg_tilemap;
@@ -42,7 +50,6 @@ public:
 	int        m_bit14;
 
 	/* device */
-	device_t *m_audiocpu;
 	device_t *m_s2636_1;
 	device_t *m_s2636_2;
 	device_t *m_s2636_3;