无法检测到FX3

FX3SDK没有VANDION请求示例，所以，我只想写一个，
但是，当我下载时，无法检测到FX3，
谁给我一些建议？谢谢您。。



     以下为原文
  the fx3 SDK did not have  vend_request sample,so,I just want to write one,
    but,when I download,fx3 can not be detected,,,,
    who just give me some advices?thank you..