AT commands Send/receive SMS

Question

I am new to AT commands. I am using Nokia E71 to send and receive SMS. I am designing an application for sending SMS, but my code is not working.

using Syste         


        

Answer 1

Try it this way.. You are not opening the connection to the serial port. I have tried it and it is working fine for me.

 private void button1_Click(object sender, EventArgs e)
 {
     this.serialPort = new SerialPort();
     this.serialPort.PortName = "COM5";
     this.serialPort.BaudRate = 9600;
     this.serialPort.Parity = Parity.None;
     this.serialPort.DataBits = 8;
     this.serialPort.StopBits = StopBits.One;
     this.serialPort.Handshake = Handshake.RequestToSend;
     this.serialPort.DtrEnable = true;
     this.serialPort.RtsEnable = true;
     this.serialPort.NewLine = System.Environment.NewLine;
     serialPort.Open();
     send_sms();
 }
 public bool send_sms()
 {
     String SMSMessage = "gsm MESSAGE FROM .NET C#";
     String CellNumber = "+9233333333333";
     String messageToSend = null;
     if (SMSMessage.Length <= 160)
     {
         messageToSend = SMSMessage;
     }
     else
     {
         messageToSend = SMSMessage.Substring(0, 160);
     }
     if (serialPort.IsOpen)
     {
         this.serialPort.WriteLine(@"AT" + (char)(13));
         Thread.Sleep(200);
         this.serialPort.WriteLine("AT+CMGF=1" + (char)(13));
         Thread.Sleep(200);
         this.serialPort.WriteLine(@"AT+CMGS=""" + CellNumber + @"""" + (char)(13));
         Thread.Sleep(200);
         this.serialPort.WriteLine(SMSMessage + (char)(26));
         return true;
         }
     return false;
 }