Problem sending SMS with Wavecom modem

Hi,
I’m having trouble to sending sms with a Wavecom modem.
I tested with the Hyperterminal and works great.
It’s possible that the MAX3232 has burned? Can I test it?

The power supply of the modem are independent of the Arduino.

It’s possible that the MAX3232 has burned? Can I test it?

It’s not impossible but not very likely to be that.
Do you have a common ground right?
Some years ago I develop a class to deal with Siemens mc35i modems.
My method to send a SMS is like this:

void GSM::sendSMS(char * destination, char * message)
	{
 		Serial.println("AT+CMGF=1"); //Set the modem in SMS mode
 		delay(modemDelay);                   //Waits for 500ms important!!!
 		Serial.print("AT+CMGS=");    //AT command for start the SMS send
 		Serial.print(destination);//Insert the destination number
 		Serial.println();            //Give a new line
 		delay(modemDelay);       //Waits for 500ms
 		Serial.print(message);//Seends the message
 		Serial.write(0x1a);    //Seend a CTRL-Z for end the text insertion
 	}

It should work as well with the Wavecom
Apart from that you problem could be wrong pins (swapped TX and RX) so I would recommend you to test it with putty to be sure your modem is working fine with the MAX3232

Thank you for the reply, i will test it.
I connected the gnd of the arduino to the MAX3232 and then to the pin 5 of the DB9 (Wavecom).

PS: Se somos os dois portugueses porque estamos a escrever em inglês???? :stuck_out_tongue_closed_eyes:

I tested with the hyperterminal (COM port where arduino is connected) and don't receive the "OK" from de modem..... Try connect directly with a RS232 converter to the modem and works fine. Then I connect the MAX3232 to RS232 converter and don't see any msg on the hyperterminal.
Probably my MAX3232 is burned. :frowning:

Probably my MAX3232 is burned. smiley-sad

Could be, why not test it correctly to be sure of that.
A simple way of doing the test is making an echo from one Serial port to another ,connecting the RS232 signal in one side of the converter and listen the other side using the arduino.
Then open 2 serial ports (putty) and what you send in one side must be output on the other Serial port.
Repeat the test in both directions and you will have your answer.

PS: Se somos os dois portugueses porque estamos a escrever em inglês???? smiley-yell

Simples porque tu vieste perguntar no fórum na secçao em Inglês, relembro-te que existe uma secçao em Português no forum :grin: :grin:

Good news!!!
Finally I can send the sms.
I tested the max3232 connected to the rs232 converter and I see the messages in Hyperterminal, then I connect the max3232 to the modem and then sms has been sent.
I don´t no what I do, but it works now. :grin:

thank you!

Excusme sir, I have same problem with you. My arduino don't send message, can you help me sir please. Sorry my English very bad :frowning: