SIM800L change default baud rate I am using an ATmega328P with internal clock (8 MHz) with a SIM800L module. The default baud rate of the SIM800L is 115,200 baud and I can't make them talk to each other correctly. Although I was able to make them talk very easily at a baud rate of 9600 baud. But now, with a new SIM800L I can't. 

Question: 

How to change the default baud rate of a SIM800L?
Is it possible to run an ATmega328P at a baud rate of 115,200 baud?

Thanks in advance!

EDIT:

I know that I can run atmega328p at baud rate of 115200 with different crystal, but is it possible to it using internal crystal.
As you say, SIM800L default baud rate is 115200. So, you have to set that baud rate on arduino side. And yes, it is possible to run an ATmega328P at a baud rate of 115200 baud.

You can use the SoftwareSerial library and define your own tx and rx pin and set baud rate according to your requirement.

#include &lt;SoftwareSerial.h&gt;   // SoftwareSerial library
SoftwareSerial mySerial(2,3); // RX, TX for your module

void setup()
{
   mySerial.begin(115200);      // Set your buad rate
}


And you can also do without this library.

void setup()
{
  Serial.begin(115200);        // Set your baud rate
}