diff --git a/src/mame/drivers/timeplt.c b/src/mame/drivers/timeplt.c
index 6f9e99c9bf0..65bbd8d47fe 100644
--- a/src/mame/drivers/timeplt.c
+++ b/src/mame/drivers/timeplt.c
@@ -377,10 +377,10 @@ static INPUT_PORTS_START( chkun )
 	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_DIPNAME( 0x40, 0x40, DEF_STR( Unknown ) ) // debug mode
 	PORT_DIPSETTING(    0x40, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )
-	PORT_DIPNAME( 0x80, 0x80, DEF_STR( Unknown ) )
+	PORT_DIPNAME( 0x80, 0x00, DEF_STR( Unknown ) ) // Freeze?
 	PORT_DIPSETTING(    0x80, DEF_STR( Off ) )
 	PORT_DIPSETTING(    0x00, DEF_STR( On ) )