diff --git a/src/mame/drivers/armedf.cpp b/src/mame/drivers/armedf.cpp
index 21c19d4d74f..e2a9dd65b3a 100644
--- a/src/mame/drivers/armedf.cpp
+++ b/src/mame/drivers/armedf.cpp
@@ -1265,6 +1265,10 @@ static MACHINE_CONFIG_START( terrafjb, armedf_state )
 	MCFG_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.80)
 MACHINE_CONFIG_END
 
+static MACHINE_CONFIG_DERIVED( terrafb, terraf )
+	MCFG_DEVICE_REMOVE("nb1414m4")
+MACHINE_CONFIG_END
+
 static MACHINE_CONFIG_START( kozure, armedf_state )
 
 	/* basic machine hardware */
@@ -2190,7 +2194,7 @@ GAME( 1987, terraf,   0,        terraf,   terraf,   armedf_state,   terrafu,  RO
 GAME( 1987, terrafu,  terraf,   terraf,   terraf,   armedf_state,   terrafu,  ROT0,   "Nichibutsu USA",                "Terra Force (US)", MACHINE_SUPPORTS_SAVE )
 GAME( 1987, terrafj,  terraf,   terraf,   terraf,   armedf_state,   terrafu,  ROT0,   "Nichibutsu Japan",              "Terra Force (Japan)", MACHINE_SUPPORTS_SAVE )
 GAME( 1987, terrafjb, terraf,   terrafjb, terraf,   armedf_state,   terrafjb, ROT0,   "bootleg",                       "Terra Force (Japan, bootleg with additional Z80)", MACHINE_SUPPORTS_SAVE )
-GAME( 1987, terrafb,  terraf,   terraf,   terraf,   armedf_state,   terraf,   ROT0,   "bootleg",                       "Terra Force (Japan, bootleg set 2)", MACHINE_SUPPORTS_SAVE )
+GAME( 1987, terrafb,  terraf,   terrafb,  terraf,   armedf_state,   terraf,   ROT0,   "bootleg",                       "Terra Force (Japan, bootleg set 2)", MACHINE_SUPPORTS_SAVE )
 
 GAME( 1987, kozure,   0,        kozure,   kozure,   armedf_state,   kozure,   ROT0,   "Nichibutsu",                    "Kozure Ookami (Japan)", MACHINE_SUPPORTS_SAVE )
 
diff --git a/src/mame/drivers/segas16b.cpp b/src/mame/drivers/segas16b.cpp
index c6cf7a58f63..2a270be05ec 100644
--- a/src/mame/drivers/segas16b.cpp
+++ b/src/mame/drivers/segas16b.cpp
@@ -1127,7 +1127,8 @@ WRITE16_MEMBER( segas16b_state::standard_io_w )
 			//  D0 : Output to coin counter 1
 			//
 			m_segaic16vid->tilemap_set_flip(0, data & 0x40);
-			m_sprites->set_flip(data & 0x40);
+			if (m_sprites.found())
+				m_sprites->set_flip(data & 0x40);
 			if (!m_disable_screen_blanking)
 				m_segaic16vid->set_display_enable(data & 0x20);
 			output().set_led_value(1, data & 0x08);
diff --git a/src/mame/video/sega16sp.cpp b/src/mame/video/sega16sp.cpp
index 4956d5e4398..3629072e2e5 100644
--- a/src/mame/video/sega16sp.cpp
+++ b/src/mame/video/sega16sp.cpp
@@ -869,7 +869,7 @@ void sega_sys16b_sprite_device::draw(bitmap_ind16 &bitmap, const rectangle &clip
 	//
 
 	// render the sprites in order
-	const UINT16 *spritebase = reinterpret_cast<const UINT16 *>(&m_sprite_region_ptr[0]);
+	const UINT16 *spritebase = &m_sprite_region_ptr[0];
 	UINT8 numbanks = m_sprite_region_ptr.bytes() / 0x20000;
 	UINT16 *ramend = spriteram() + spriteram_elements();
 	for (UINT16 *data = spriteram(); data < ramend; data += 8)
diff --git a/src/mame/video/sega16sp.h b/src/mame/video/sega16sp.h
index 34d50676172..f3b462f788a 100644
--- a/src/mame/video/sega16sp.h
+++ b/src/mame/video/sega16sp.h
@@ -203,7 +203,7 @@ protected:
 	virtual void draw(bitmap_ind16 &bitmap, const rectangle &cliprect) override;
 
 	// memory regions
-	optional_region_ptr<UINT8> m_sprite_region_ptr;
+	required_region_ptr<UINT16> m_sprite_region_ptr;
 };