Arduino y SIM900

Hola a todos;bueno Mi problema es el siguente tengo un arduino mega 2560 y trato de comunicarlo con una shield sim900 de geeetech y ya busque informacion y hice los cableados correspondientes al Tx1 y Rx1
y utilice este codigo

#include <SoftwareSerial.h>
#define terminator 10 // DEC value for a LF(line feed) to skip while loop

String IncDataSerial = "";

void setup()
{
delay(1000);
Serial.begin(19200);
Serial1.begin(19200);

// Automatically power up the SIM900.
pinMode(9, OUTPUT);
digitalWrite(9,LOW);
delay(1000);
digitalWrite(9,HIGH);
delay(2500);
digitalWrite(9,LOW);
delay(3500);
// End of SIM900 power up.
}

void loop()
{
if (Serial1.available()>0) // if date is comming from softwareserial port ==> data is comming from gprs shield
{
boolean getLF = false;
while(Serial1.available()>0 && !getLF) // reading data into string if activity is on port and getLF is false ==> no LF have been send
{
char buffer=Serial1.read(); // writing data into char
IncDataSerial += buffer;
if (buffer == terminator) {
getLF = true;
}
}

Serial.print(IncDataSerial); // send string ( char array ) to hardware serial
Serial.print("\r"); // send a CR because it is missing
IncDataSerial = "";
}
if (Serial.available()>0) // if data is available on hardwareserial port ==> data is comming from PC or notebook
Serial1.write(Serial.read()); // write it to the GPRS shield
}

y no me da el mensaje de bienvenida que deveria ser este
RDY

+CFUN: 1

+CPIN: READY
por favor ayudenmeee!!!!!!!!! : '( : '( : '(

sketch_dec31a.ino (1.22 KB)