There are something I want to say sorry.
1. I posted this topic on other page, then I find that it maybe in a wrong place, so I copy it to here. When I back to delete the original post, a reply was there in that few minutes, so I had no authority to remove the original topic. You can click the following link to see it. http://arduino.cc/forum/index.php/topic,65160.msg476148.html#msg476148
2. My English is really poor, because English is not our mother language. Hope it will be better in the future by our hard working.
3. Thanks the two friends below, your any kindly suggestions are greatly appreciated.