The invention provides a circuit device for controlling N light-emitting
devices disposed in a sequence on an object, wherein N is an integer
larger than 1, and each light-emitting device includes a respective
light-emitting diode. The circuit device includes a water-proof
enclosure, a motion-actuated switch, a controller, and a battery.
Particularly, the controller is capable of driving the light-emitting
diodes lighting up on the basis of a first predefined sequence and a
consequent second predefined sequence when triggered by the
motion-actuated switch.