AT+MCONFIG="12345|securemode=3,signmethod=hmacsha1,timestamp=789|","test-mqtt&a1VkWHdq1Hl","81a522fb1babee4c9b642f55e31de0ce1e6a4079",1,0,"/a1VkWHdq1Hl/test-mqtt/update","online"\r
发送这个AT指令时一直返回错误
V524以后的版本已解决该问题,关闭问题