I can not read text messages with Siemens tc35

Other Hardware Home Automation
1

I'm trying to read a text message but the content is missing.

at
OK
AT+CPIN=5134
OK
AT+CMGF=1
OK
AT+CMGR=1
+CMGR: "REC READ","+3598833485**",,"13/04/03,17:07:

char gsm_char=0; //Stores character from the gsmSerial

void setup()
{
//Initialize serial ports for communication.
Serial.begin(9600);
Serial1.begin(9600);
Serial.println("Starting TC35 and debug Communication...");
}

void loop() {
//If a character comes in from the cellular module...
if(Serial1.available() > 0){
gsm_char=Serial1.read(); //Store the char in gsm_char.
Serial.print(gsm_char); //Print it to debug serial
}
//Read serial input
if(Serial.available() > 0){
gsm_char=Serial.read(); //Store char in gsm_char (Not really from the gsm, just saving some memory)
//Evaluate input.
if(gsm_char=='t'){
Serial1.print("AT\r"); //Send test command
} else if(gsm_char=='p'){
Serial1.print("AT+CPIN=5134\r"); //Enter pin, hardcoded
} else if(gsm_char=='g'){
Serial1.print("AT+CMGF=1\r"); //Set text mode.
} else if(gsm_char=='s'){
//Send sms!
Serial1.print("AT+CMGR=1\r"); //AT command to send SMS
} else if(gsm_char=='z'){

}
}
}

Is it possible to buffer overflows?

2

I found that the problem is communication between Arduino and GSM module because when I connect GSM module to the serial port of the computer, the message is read. Where is the error in my program?

3

I've the same problem. Have you a solution? My program read only 31 bytes.
Thanks you

4

Hi!

The voltage level of TC35 UART TTL is 2.65v.
The minimum value for detecting a logic high is VDD*0.6. For a 5v Arduino that is 3V.

Maybe that is your problem.

I have a TC35 module and convert the voltage to 5v with two transistors.
Reading SMS works fine for me.

/Olof

5

I have link arduino and a TC35 module by an MAX232 adapter. Serial comunication work fine but I don't understand why sms is truncated. I think that serial overflow is the real cause

6

I checked my code and I use the AltSoftSerial library.
http://www.pjrc.com/teensy/td_libs_AltSoftSerial.html

I remember that the normal softwareserial gave me some problem (do not remember what problem).

7

FRIENDS Hello, my name Elnur Qulamov, I am from Azerbaijan
about two days I'm working on a project, I, too, was impossible to read the sms TC35, and finally I thought, I realized that the TC35 does not have its memory to store SMS, connect the terminal to the TC35 and clean memory SIM card then see it will work if you have questions please contact us by email