nodemcu doesnt response in at command mode I want to sent AT command into node mcu esp8266 module with arduino IDE  through serial monitor.
I connect the node mcu to arduino uno board in following sequence:
RX to pin 2 of arduino
TX to pin 3 of arduino
Vin of node mcu to 3.3V of arduino
GND to GND 
EN of node mcu to 3.3V of arduino
I send at commands in serial monitor but dont get any response.
I also checked different baud rates.
what is the problem? what thing I'm doing wrong?

    #include &lt;SoftwareSerial.h&gt;
SoftwareSerial esp8266(2,3); //2 --&gt;rx  ,3 --&gt;tx

void setup() {
  Serial.begin(115200);
  esp8266.begin(115200);
}

void loop() {
  if (esp8266.available()&gt;0)
  {
      char c = esp8266.read();
      Serial.write(c);
  }
  if (Serial.available()&gt;0)
  {
    delay(1000);
    String cmd = "";
    while (Serial.available())
    {
      cmd += (char)Serial.read();
    }
    esp8266.println(cmd);
  }
}
Some points to note:


VIN should connect to 5V (it goes through the on-board 5V -> 3.3V regulator). If you connect VIN to 3.3V you will be starving the device of power.
The NodeMCU doesn't come with AT firmware installed. You will have to install it first before it will respond. 
If you have a NodeMCU why are you bothering with an Arduino? The NodeMCU can do everything (and more) that the Arduino can do (except it lacks IO).