diff --git a/src/mame/drivers/micro3d.c b/src/mame/drivers/micro3d.c
index f2399554d37..abbca838f52 100644
--- a/src/mame/drivers/micro3d.c
+++ b/src/mame/drivers/micro3d.c
@@ -36,10 +36,10 @@
 
 static INPUT_PORTS_START( micro3d )
 	PORT_START("INPUTS_A_B")
-	PORT_DIPNAME( 0x0001, 0x0000, DEF_STR( Unused ) )
+	PORT_DIPNAME( 0x0001, 0x0001, DEF_STR( Unused ) )
 	PORT_DIPSETTING(      0x0001, DEF_STR( Off ) )
 	PORT_DIPSETTING(      0x0000, DEF_STR( On ) )
-	PORT_DIPNAME( 0x0002, 0x0000, DEF_STR( Unused ) )
+	PORT_DIPNAME( 0x0002, 0x0002, DEF_STR( Unused ) )
 	PORT_DIPSETTING(      0x0002, DEF_STR( Off ) )
 	PORT_DIPSETTING(      0x0000, DEF_STR( On ) )
 	PORT_DIPNAME( 0x0004, 0x0000, "Shared Memory Handshake Test")
@@ -54,7 +54,7 @@ static INPUT_PORTS_START( micro3d )
 	PORT_DIPNAME( 0x0020, 0x0000, "Manufacturing Tests")
 	PORT_DIPSETTING(      0x0000, DEF_STR( Off ) )
 	PORT_DIPSETTING(      0x0020, DEF_STR( On ) )
-	PORT_DIPNAME( 0x0040, 0x0000, DEF_STR( Unused ) )
+	PORT_DIPNAME( 0x0040, 0x0040, DEF_STR( Unused ) )
 	PORT_DIPSETTING(      0x0040, DEF_STR( Off ) )
 	PORT_DIPSETTING(      0x0000, DEF_STR( On ) )
 	PORT_DIPNAME( 0x0080, 0x0000, "Host Monitor Mode")
diff --git a/src/mame/machine/micro3d.c b/src/mame/machine/micro3d.c
index 304e8b01f4d..f20ffcc110a 100644
--- a/src/mame/machine/micro3d.c
+++ b/src/mame/machine/micro3d.c
@@ -736,6 +736,11 @@ DRIVER_INIT( micro3d )
 	memory_write_dword(space, 0x00470000, 0xa5a5a5a5);
 
 	state->mc68901.timer_a = timer_alloc(machine, mfp_timer_a_cb, NULL);
+
+	/* TODO? BOTSS crashes when starting the final stage because the 68000
+	overwrites memory in use by the Am29000. Slowing down the 68000 slightly
+	avoids this */
+	cpu_set_clockscale(devtag_get_device(machine, "maincpu"), 0.945f);
 }
 
 MACHINE_RESET( micro3d )