由服务器往设备下发控制指令; 控制指令格式如下: ``` 例如:{"dev_id":"9tw3xz","api_id":1,"argv":["115200","1.5","8","1"],"fd":"56","type":""} ``` dev_id:设备号 api_id:指令ID argv:指令参数,如下图所示:当没有参数时:"argv"则未被下发。 ![](https://img.kancloud.cn/e4/4c/e44c1bc238369f7c23f918633a66a62b_749x390.png) ![](https://img.kancloud.cn/60/39/60396f264032a1ec63abec00b57a9d64_747x459.png)