ESP8266, prints ready at start but no response to AT command I have been using ESP8266 wifi module with Arduino as FTDI. The power for ESP8266 comes from LM317 5V - 3.3v regulated supply(I am sure 5V is powerful enough to give upto 1A of current).

The RX of ESP8266 is connected to RX of Arduino via a voltage divider to ensure 3.3V logic level. But still, I am not getting any response to AT command, though my laptop and phone wifi have successfully connected to AI-Thinker... SSID(which is an open hotspot from ESP8266).

I am also having some garbage values on the serial port immediately after I turn on the power supply to ESP8266. I have tested all baud rates available in Arduino IDE v1.0.5 with no results.

The resistor values for lm317 are R1 = 125 Ohm, R2 = 225 Ohm with which I am getting around 3.2 Volts.

The connections are as follows:-



-----Arduino UNO-----

RESET ------------ GND



Arduino UNO ----- ESP8266

TX ------------------- TX

RX ---5V to 3.3v--- RX

GND ----------------- GND



ESP8266 --------- LM317(5V to 3.3V)

VCC --------------- 3.3V

GND --------------- GND

CH_PD ------------ 3.3V





EDIT - 1: I have bought a new ESP8266, and even it doesn't responds to any AT commands, thought there is some difference in the previous ESP8266 output and this new ESP8266 output.

The difference is a sort of good news to me, it sends ready after sending some garbage at 115200 baud on boot which never happened with previous one(ESP8266).

Is anyone having some clue why there is no response to AT commands?
May it be a issue with TX line?



EDIT - 2: I have also used another Arduino with same connections doubting the TX pin on Arduino, but with same luck, bad luck. Still, nothing got changed.



EDIT - 3: I am shifting 5v to 3.3v by using three 100 ohm resistors.
Connect TX of arduino to esp8266 RX, and arduino RX to esp8266 TX. 

See this link for more info.