To setup the top limit, open the drape/shade.
Press the back button plus the up button at the same time for 4 seconds, the motor will quiver or the light comes on.
Press the up [button] to make the curtain moving upwards, and stop at the needed upper position.
Press Slight up or Slight down buttons to set upper limit position with slight rotation of the motor.
Press the back button for 4 seconds, the motor quivers.