at命令+ CME错误：4 C＃

Question

请按命令帮助wavecom：

回复：

+ STIN：3 + STGI：0,1,8,8,0，“日期:(例如：12081965）”

行 AT + STGR = 3,1

  

12192011

+ CME错误：4

port.DataBits = 8;
port.StopBits = StopBits.One;
port.Parity = Parity.None;
port.ReadTimeout = 800;
port.WriteTimeout = 800;
port.Encoding = Encoding.GetEncoding("iso-8859-1");
port.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);
port.Open();
port.DiscardOutBuffer();
port.DiscardInBuffer();

port.WriteLine("AT+STGR=3,1\r");

Thread.Sleep(100);

port.WriteLine("12192011" + (char)36);