diff --git a/src/mame/drivers/jangou.cpp b/src/mame/drivers/jangou.cpp
index b6f011f0a50..3a0bfc890b8 100644
--- a/src/mame/drivers/jangou.cpp
+++ b/src/mame/drivers/jangou.cpp
@@ -506,22 +506,21 @@ static INPUT_PORTS_START( jangou )
 
 	/* there's a bank of 6 dip-switches in there*/
 	PORT_START("DSW")
-	PORT_DIPNAME( 0x01, 0x01, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:1")
-	PORT_DIPSETTING(    0x01, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x02, 0x02, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:2")
-	PORT_DIPSETTING(    0x02, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:3")
+	PORT_DIPNAME( 0x03, 0x03, DEF_STR( Difficulty ) ) PORT_DIPLOCATION("SW1:1,2")
+	PORT_DIPSETTING(    0x03, DEF_STR( Easy ) )
+	PORT_DIPSETTING(    0x01, DEF_STR( Normal ) )
+	PORT_DIPSETTING(    0x02, DEF_STR( Hard ) )
+	PORT_DIPSETTING(    0x00, DEF_STR( Very_Hard ) )
+	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Unused ) )     PORT_DIPLOCATION("SW1:3")
 	PORT_DIPSETTING(    0x04, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:4")
+	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Unused ) )     PORT_DIPLOCATION("SW1:4")
 	PORT_DIPSETTING(    0x08, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x10, 0x10, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:5")
+	PORT_DIPNAME( 0x10, 0x10, DEF_STR( Unused ) )     PORT_DIPLOCATION("SW1:5")
 	PORT_DIPSETTING(    0x10, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Unknown ) ) PORT_DIPLOCATION("SW1:6")
+	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Unused ) )     PORT_DIPLOCATION("SW1:6")
 	PORT_DIPSETTING(    0x20, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
 	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_CUSTOM ) PORT_VBLANK("screen") // guess
diff --git a/src/mame/drivers/nbmj8891.cpp b/src/mame/drivers/nbmj8891.cpp
index 8789b170c3e..fd21b7534b8 100644
--- a/src/mame/drivers/nbmj8891.cpp
+++ b/src/mame/drivers/nbmj8891.cpp
@@ -1096,31 +1096,9 @@ static INPUT_PORTS_START( mgmen89 )
 	PORT_DIPSETTING(    0x80, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
 
+	/* does not physically exist on PCB */
 	PORT_START("DSWB")
-	PORT_DIPNAME( 0x01, 0x01, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x01, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x02, 0x02, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x02, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x04, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x08, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x10, 0x10, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x10, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x20, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x40, 0x40, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x40, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x80, 0x80, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x80, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
+	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
 
 	PORT_START("SYSTEM")
 	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, nbmj8891_state, nb1413m3_busyflag_r, nullptr)    // DRAW BUSY
diff --git a/src/mame/drivers/nbmj8991.cpp b/src/mame/drivers/nbmj8991.cpp
index 9a956e3090b..f1ff6c70afb 100644
--- a/src/mame/drivers/nbmj8991.cpp
+++ b/src/mame/drivers/nbmj8991.cpp
@@ -473,55 +473,39 @@ INPUT_PORTS_END
 
 static INPUT_PORTS_START( vanilla )
 	PORT_START("DSWA")
-	PORT_DIPNAME( 0x03, 0x03, DEF_STR( Difficulty ) )
+	PORT_DIPNAME( 0x03, 0x03, DEF_STR( Difficulty ) )       PORT_DIPLOCATION("DSWA:1,2")
 	PORT_DIPSETTING(    0x03, "1 (Easy)" )
 	PORT_DIPSETTING(    0x02, "2" )
 	PORT_DIPSETTING(    0x01, "3" )
 	PORT_DIPSETTING(    0x00, "4 (Hard)" )
-	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Coinage ) )
+	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Coinage ) )          PORT_DIPLOCATION("DSWA:3")
 	PORT_DIPSETTING(    0x04, DEF_STR( 1C_1C ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( 1C_2C ) )
-	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Demo_Sounds ) )
+	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Demo_Sounds ) )      PORT_DIPLOCATION("DSWA:4")
 	PORT_DIPSETTING(    0x00, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x08, DEF_STR( On ) )
-	PORT_DIPNAME( 0x10, 0x10, "Game Sounds" )
+	PORT_DIPNAME( 0x10, 0x10, "Game Sounds" )               PORT_DIPLOCATION("DSWA:5")
 	PORT_DIPSETTING(    0x00, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x10, DEF_STR( On ) )
-	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Flip_Screen ) )
+	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Flip_Screen ) )      PORT_DIPLOCATION("DSWA:6")
 	PORT_DIPSETTING(    0x20, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x40, 0x40, "Character Display Test" )
+	PORT_DIPNAME( 0x40, 0x40, "Character Display Test" )    PORT_DIPLOCATION("DSWA:7")
 	PORT_DIPSETTING(    0x40, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x80, 0x80, "Graphic ROM Test" )
+	PORT_DIPNAME( 0x80, 0x80, "Graphic ROM Test" )          PORT_DIPLOCATION("DSWA:8") // Marked as unused in manual
 	PORT_DIPSETTING(    0x80, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
 
 	PORT_START("DSWB")
-	PORT_DIPNAME( 0x01, 0x01, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x01, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x02, 0x02, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x02, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x04, 0x04, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x04, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x08, 0x08, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x08, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x10, 0x10, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x10, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x20, 0x20, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x20, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x40, 0x40, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x40, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x80, 0x80, DEF_STR( Unknown ) )
-	PORT_DIPSETTING(    0x80, DEF_STR( Off ) )
-	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
+	PORT_DIPUNUSED_DIPLOC( 0x01, 0x01, "DSWB:1" )
+	PORT_DIPUNUSED_DIPLOC( 0x02, 0x02, "DSWB:2" )
+	PORT_DIPUNUSED_DIPLOC( 0x04, 0x04, "DSWB:3" )
+	PORT_DIPUNUSED_DIPLOC( 0x08, 0x08, "DSWB:4" )
+	PORT_DIPUNUSED_DIPLOC( 0x10, 0x10, "DSWB:5" )
+	PORT_DIPUNUSED_DIPLOC( 0x20, 0x20, "DSWB:6" )
+	PORT_DIPUNUSED_DIPLOC( 0x40, 0x40, "DSWB:7" )
+	PORT_DIPUNUSED_DIPLOC( 0x80, 0x80, "DSWB:8" )
 
 	PORT_START("SYSTEM")
 	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_SPECIAL ) PORT_CUSTOM_MEMBER(DEVICE_SELF, nbmj8991_state, nb1413m3_busyflag_r, nullptr)    // DRAW BUSY