(After making the USB flash drive, the next step is to crack the bt4. The software we use here is spoonwep2, the download address is my.xwtop/filemy/20090517/679c13d2.1.deb, which is the deb installation under bt4 package, and then manually copy it to the root directory of the U disk, which can be named as a friendly name, such as "wep.deb", which is convenient to find it under bt4.)