diff --git a/control/walle.py b/control/walle.py
index 826d062..314783b 100644
--- a/control/walle.py
+++ b/control/walle.py
@@ -130,4 +130,4 @@ class WallE:
         minmax_rotate = SERVO_MIN_MAX[SERVO_NECK_ROTATE]
         minmax_necktop = SERVO_MIN_MAX[SERVO_NECK_TOP]
         self.set_servo(SERVO_NECK_ROTATE, map_range(left_right, -1.0, 1.0, minmax_rotate.minval, minmax_rotate.maxval))
-        self.set_servo(SERVO_NECK_TOP, map_range(up_down, -1.0, 1.0, minmax_necktop.minval, minmax_necktop.maxval))
+        self.set_servo(SERVO_NECK_TOP, map_range(up_down, 1.0, -1.0, minmax_necktop.minval, minmax_necktop.maxval))