Sending commands to Serial Port(COM1)

[ali_sakar]

Hi all,

I am new to Java and has been assigned a task which seems to be quite an Advanced Java stuff.

I have a GSM modem connected to the serial port(COM1) and I want to send AT commands to the modem(for sending sms). I searched the net but am not able to find an appropriate solution for the same.

A complete and stepwise solution would be greatly appreciable.

Thanking in advance.

Ali.

[wolfcro]

try to read about Java Communications API

Java Communications API
Java(tm) Communications API Users Guide
The Java Communications API: A Working Example - By Rick Proctor

hope it helps you

[rakesh_n_mehta]

i have done same project in my collage but i dont have its code now ...
i am giving you one link that will hepl you ...
if you still not clear then i can give you some code 2moro...


:) but first try this code...


import java.io.*;
import java.util.*;
import javax.comm.*;

public class SimpleRead implements Runnable, SerialPortEventListener {
static CommPortIdentifier portId;
static Enumeration portList;

InputStream inputStream;
SerialPort serialPort;
Thread readThread;

public static void main(String[] args) {
portList = CommPortIdentifier.getPortIdentifiers();

while (portList.hasMoreElements()) {
portId = (CommPortIdentifier) portList.nextElement();
if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
if (portId.getName().equals("COM1")) {
// if (portId.getName().equals("/dev/term/a")) {
SimpleRead reader = new SimpleRead();
}
}
}
}

public SimpleRead() {
try {
serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);
} catch (PortInUseException e) {System.out.println(e);}
try {
inputStream = serialPort.getInputStream();
} catch (IOException e) {System.out.println(e);}
try {
serialPort.addEventListener(this);
} catch (TooManyListenersException e) {System.out.println(e);}
serialPort.notifyOnDataAvailable(true);
try {
serialPort.setSerialPortParams(9600,
SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
} catch (UnsupportedCommOperationException e) {System.out.println(e);}
readThread = new Thread(this);
readThread.start();
}

public void run() {
try {
Thread.sleep(20000);
} catch (InterruptedException e) {System.out.println(e);}
}

public void serialEvent(SerialPortEvent event) {
switch(event.getEventType()) {
case SerialPortEvent.BI:
case SerialPortEvent.OE:
case SerialPortEvent.FE:
case SerialPortEvent.PE:
case SerialPortEvent.CD:
case SerialPortEvent.CTS:
case SerialPortEvent.DSR:
case SerialPortEvent.RI:
case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
break;
case SerialPortEvent.DATA_AVAILABLE:
byte[] readBuffer = new byte[20];

try {
while (inputStream.available() > 0) {
int numBytes = inputStream.read(readBuffer);
}
System.out.print(new String(readBuffer));
} catch (IOException e) {System.out.println(e);}
break;
}
}
}

[ali_sakar]

Hi Rakesh,

Thanx for the update. I tried running the above code but it is not able to import javax.comm and therefore it gives a lot of compilation errors. And I believe this code is to read from the Serial Port whereas I want to send commands to the port. How do I go about?
I have one more piece of code as below. It gets compiled successfully but it does not send the sms. When I try to send the same commands from hyperterminal, it works fine and sms is also sent.

package serialport;

import java.io.BufferedOutputStream;
import java.io.FileOutputStream;

public class SerialTest {
//static byte[] newline[]={(byte)13,(byte)10};

public static void main( String args[]) {
Runtime rt = Runtime.getRuntime();
Process p = null;
String portname = "COM1";
// for Win95 : c:\\windows\\command.com
// c:\\windows\\command\\mode.com
String cmd[] = {
"c:\\windows\\system32\\cmd.exe", "/c",
"start", "/min",
"c:\\windows\\system32\\mode.com", portname,
"baud=9600", "parity=n", "data=8",
"stop=1",
};
try {
p = rt.exec( cmd );
if( p.waitFor() != 0 ) {
System.out.println("Error executing command: " + cmd );
System.exit( -1 );
}
byte data[] =
"AT+CMGS=\"9819143791\",\"Hello there".getBytes();
FileOutputStream fos = new FileOutputStream( portname );
BufferedOutputStream bos = new BufferedOutputStream( fos );
fos.write( data, 0, data.length );
fos.close();
}
catch( Exception e ) {
e.printStackTrace();
}
}
}

I found this code from this forum only. Could you pls. tell me that why SMS is not being sent by this code??

Thanking in advance.

Regards
Ali.

[rakesh_n_mehta]

hey you have to download jar file for communication....
than ur problem will be solved

[rakesh_n_mehta]

have u found comm jar file??
is code working now???:confused::confused::confused:

[ali_sakar]

No buddy,

Still hunting for the same. I am checking on sun.com but till now no luck... could u help in this as well...??

[rakesh_n_mehta]

ok giving u some file ...try it and infor me later

[ali_sakar]

Thanx a lot rakesh... I am using JDeveloper 11g and now its getting compiled and runs w/o errors. Sorry to trouble you more but do you know AT commands that we use in the Hyperterminal. What I need this class to do is send the below command to COM1.

AT+CMGS="9819143791" <CR>
Hi... <Ctrl z>

[rakesh_n_mehta]

your welcome..

i have downloaded some file for at commmand.. here they are...
hope that will help u..

hey its size is too much ... not able too send u..
search at command in google u will find some thing other wise give me ur mail add..

[ali_sakar]

I think you have misunderstood me.. I dont need the AT commands... I want to send the below commands to the modem via serial port.

AT+CMGS="9819143791" <CR>
Hi... <Ctrl z>

I want to know how do i implement this in a class. I have got this code.

******************************
package serialport;

import java.io.*;
import java.util.*;
import javax.comm.*; //for accessing serialport

public class OwnPort {
static CommPortIdentifier portId;
static CommPortIdentifier saveportId;
static Enumeration portList;
static SerialPort serialPort;
static OutputStream outputStream;
static InputStream inputStream;
static boolean outputBufferEmptyFlag = false;
public static void main(String[] args) {
boolean portFound = false;
String defaultPort= "COM1";
System.out.println("Set default port to "+defaultPort);
portList = CommPortIdentifier.getPortIdentifiers();
while (portList.hasMoreElements()) {
portId = (CommPortIdentifier) portList.nextElement();
if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
if (portId.getName().equals(defaultPort)) {
System.out.println("Found port: "+defaultPort);
portFound = true;
// init reader thread
OwnPort op=new OwnPort();
op.initwritetoport();
}
}

}
if (!portFound) {
System.out.println("port " + defaultPort + " not found.");
}
}
public void initwritetoport()
{
System.out.println("inside initwriteport");
String s1="at";
String s2="\r\n";
String s3="at+cmgf=1";
String s4="at+cmgs=\"9819143791\"";
// char[] s5={’"‘,’9',’3',’4',’6',’4',’6',’2',’1',’6',’5',’" ‘};
String s6="32";
// for(int i=0;i<s5.length;i++)
// {
// System.out.println(s5.toString());
// }
// System.out.println("s6="+s6);
String messageString = "hey ee mesage GSM nunchi vachindi!";

// get the outputstream
try {
serialPort = (SerialPort) portId.open("SimpleReadApp", 2000);
} catch (PortInUseException e) {}

try {
// set port parameters
serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
outputStream =serialPort.getOutputStream();
inputStream = serialPort.getInputStream();
}
catch (Exception e) {
e.printStackTrace();
}
try
{
System.out.println("–1–");
outputStream.write(s1.getBytes()); // AT command
// System.out.println(s1.getBytes());
// outputStream.wait(10000);
outputStream.write(s2.getBytes()); // enter
Thread.sleep(1000); //sleeping thread
System.out.println("–2–");
// outputStream.wait(1000);
outputStream.write(s3.getBytes()); //at+cmgf=1 command
// outputStream.wait(1000);
outputStream.write(s2.getBytes()); //enter
Thread.sleep(1000);// thread sleeping
System.out.println("–3–");
// outputStream.wait(1000);
outputStream.write(s4.getBytes()); //at+cmgs="<mobilenumber>"
// outputStream.wait(1000);
outputStream.write(s2.getBytes()); //enter
Thread.sleep(1000); //thread sleeping
System.out.println("–4–");
// outputStream.wait(1000);
outputStream.write(messageString.getBytes()); // message
// outputStream.wait(1000);
outputStream.write(s2.getBytes());
Thread.sleep(1000);
outputStream.write(s6.getBytes());
Thread.sleep(1000);
System.out.println("–5–");

// outputStream.wait(1000);
byte[] readBuffer = new byte[23];
try
{
while (inputStream.available() > 0) {
int numBytes = inputStream.read(readBuffer);
// System.out.println(numBytes);

// print data

String result = new String(readBuffer);
System.out.println("Read: "+result);
}
}
catch(Exception e)
{
e.printStackTrace();
}
outputStream.close();
serialPort.close();
}
catch(Exception e)
{

}

}
}

******************************
When I run the above code, I get this o/p

Set default port to COM1
port COM1 not found.
Process exited with exit code 0.

but when if I try from hyperterminal, sms goes.
I m unable to understand the problem.

[ali_sakar]

Its not going in the while loop

while (portList.hasMoreElements())
but why its not going that I dont understand.

[rakesh_n_mehta]

hey in this type of project you have to check so much things...
like mobile you r using have internal memory or memory card...
command supported in that or not that typr of error u can get in ur consol area.. but they r that..

[ali_sakar]

Hi rakesh,

I have achieved almost everything except for sending ctrl+z key. Could you help in that??

I am able to send commands and text to the port and then when I connect to hyperterminal and press ctrl+z all the text which i sent from the java class goes in the sms. Are you mumbai based.. is it possible to talk on phone?

Regards
Ali.

[ali_sakar]

Hey Rakesh,

I have done it. Now its working using JDeveloper. Now I am trying to send it using command line. Will bug you if I face issues in achieving it via command line. :)

Thanx a lot for all the replies.

Regards
Ali.

[rakesh_n_mehta]

thats great..

[ibanhoe]

Im new in this forum

I was looking for info about the Java app using AT commands and i found this one

I can send commands to a SMS sender device, but the event thta the Port Commm return back to me is OUTPUT_BUFFER_EMPTY always.

I could run my app a few months ago, but now i don't know why it does not run...

Could you give a suggestion about what can i looking for?

Thank you very much

Regards!!!

[kalu143_2003]

Dear Rakesh and ali

I connected internal modem in my computer and when i see the properties of modem then it display that modem is connected to COM 6.

The main problem is I have already written java code to connect to modem but the code line;

while(portList.hasMoreElements())

always return false. due to this the execution doesnt enter the while loop.

Please write me why is it returning false though there is modem in com port 6.

please reply . I am from nepal

Thank you
dipesh

[jurez]

i used gsm modem with AT command using java net bean which i include three file which in can download by comm.jar in this u find three file u should allocate according by path.


so my project is processing sms from sms modem and send the sms according to the received sms so if u want code of me i will send that u for sending and receiving command from com1 using RS232 with javax.comm header file

[iwonawas]

hi
i'm new in this forum...
i have big problem with sending only two bytes to serial port...
if my device doesn't respond on my these two bytes i must send new two bytes (the same two bytes)...
and unfortunatly this second sending doesn' work...app has blocked...killing this app doesn't work...it is killed when i plug out device...i don't receive error...nothing...
but if i send once this two bytes and device respond it is everything ok...i don't know what i do wrong...maybe i must clear sth?
please help me!!!!!!