esp8266 not responding to the AT commands I am integrating Arduino Uno with the WiFi module ESP8266.  I have already made the connections between the ESP8266 and the Arduino Uno which are :

txd uno -&gt; rxd esp8266 
rxd uno -&gt; txd esp8266  
gnd uno -&gt; gnd esp8266


The VCC and chid pind of ESP8266 are connected to an external supply of voltage 3.3V and 160mA current. The code is getting uploaded onto the Arduino and the ESP8266 is also getting powered on.But i am facing a problem while i send the AT commands on the serial monitor. It is not responding even though the red led is on constantly and when i press enter after sending the command , the blue led blinks for a few seconds.
Do i have to update the firmware of the ESP8266?
I had same problem. It helped to connect GNDs of both power supplies namely the one powering the arduino and the 3.3V one powering the ESP8266.