diff --git a/src/mame/drivers/alpha68k.c b/src/mame/drivers/alpha68k.c
index f08ef408185..45c693c241b 100644
--- a/src/mame/drivers/alpha68k.c
+++ b/src/mame/drivers/alpha68k.c
@@ -1123,11 +1123,11 @@ static INPUT_PORTS_START( timesold )
 	PORT_DIPSETTING(    0x00, "6" )
 	PORT_BIT( 0xc0, IP_ACTIVE_LOW, IPT_UNUSED )
 
-	PORT_START("IN5")  /* player 1 12-way rotary control */
-	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+	PORT_START("IN5")  /* player 1 12-way rotary control - converted in controls_r() */
+	PORT_BIT( 0x0f, 0x00, IPT_POSITIONAL ) PORT_POSITIONS(12) PORT_WRAPS PORT_SENSITIVITY(15) PORT_KEYDELTA(1) PORT_CODE_DEC(KEYCODE_Z) PORT_CODE_INC(KEYCODE_X) PORT_REVERSE PORT_FULL_TURN_COUNT(12)
 
-	PORT_START("IN6")  /* player 2 12-way rotary control */
-	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+	PORT_START("IN6")  /* player 2 12-way rotary control - converted in controls_r() */
+	PORT_BIT( 0x0f, 0x00, IPT_POSITIONAL ) PORT_POSITIONS(12) PORT_WRAPS PORT_SENSITIVITY(15) PORT_KEYDELTA(1) PORT_CODE_DEC(KEYCODE_N) PORT_CODE_INC(KEYCODE_M) PORT_PLAYER(2) PORT_REVERSE PORT_FULL_TURN_COUNT(12)
 INPUT_PORTS_END
 
 /* Same as 'timesold' but different default settings for the "Language" Dip Switch */
@@ -1173,11 +1173,11 @@ static INPUT_PORTS_START( btlfield )
 	PORT_DIPSETTING(    0x00, "6" )
 	PORT_BIT( 0xc0, IP_ACTIVE_LOW, IPT_UNUSED )
 
-	PORT_START("IN5")  /* player 1 12-way rotary control */
-	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+	PORT_START("IN5")  /* player 1 12-way rotary control - converted in controls_r() */
+	PORT_BIT( 0x0f, 0x00, IPT_POSITIONAL ) PORT_POSITIONS(12) PORT_WRAPS PORT_SENSITIVITY(15) PORT_KEYDELTA(1) PORT_CODE_DEC(KEYCODE_Z) PORT_CODE_INC(KEYCODE_X) PORT_REVERSE PORT_FULL_TURN_COUNT(12)
 
-	PORT_START("IN6")  /* player 2 12-way rotary control */
-	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+	PORT_START("IN6")  /* player 2 12-way rotary control - converted in controls_r() */
+	PORT_BIT( 0x0f, 0x00, IPT_POSITIONAL ) PORT_POSITIONS(12) PORT_WRAPS PORT_SENSITIVITY(15) PORT_KEYDELTA(1) PORT_CODE_DEC(KEYCODE_N) PORT_CODE_INC(KEYCODE_M) PORT_PLAYER(2) PORT_REVERSE PORT_FULL_TURN_COUNT(12)
 INPUT_PORTS_END
 
 static INPUT_PORTS_START( btlfieldb )
@@ -1198,6 +1198,14 @@ static INPUT_PORTS_START( btlfieldb )
 	PORT_DIPSETTING(    0x08, DEF_STR( On ) )
 	PORT_DIPUNKNOWN_DIPLOC( 0x10, 0x10, "SW1:2" )
 	PORT_DIPUNKNOWN_DIPLOC( 0x20, 0x20, "SW1:1" )
+
+	/* Bootleg does not appear to have rotary gun direction movements */
+	PORT_MODIFY("IN5")
+	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+
+	PORT_MODIFY("IN6")
+	PORT_BIT( 0xff, IP_ACTIVE_LOW, IPT_UNUSED )
+
 INPUT_PORTS_END
 
 static INPUT_PORTS_START( skysoldr )