ESP8266 Community Forum

You can use the Arduino Uno as a USB to TTL connector allowing you to communicate with the ESP8266.
BE ADVISED that the ESP8266 is rated at 3.3V and the UNO RX and TX pins are rated as 5V but i've had no issues so far.




I connected them as follows:
UNO --- ESP8266
RX ----- RX
TX ----- TX
GND --- GND
3.3V --- VCC
3.3V --- CH_PD

Breadboard may be required to connect both VCC and CG_PD to 3.3V pin
I loaded the BareMinimum sketch, so that no previous sketch causes issues.

Once Connected open the Serial Monitor and set "Both NL & CR" and Baud to 9600.
Send "AT" to test. If nothing comes up try different baud rates such as 115200 or 57600 and retest.
If you get "OK" reply then all is working.

List of commands can be found here:
AT Command List

Arduino as a webserver example:
How To Use the ESP8266 and Arduino as a Webserver
It works with my setup also just change the RX and TX pins to the same as in the video.

While it might work it might not work for a long time. I would look at a simple voltage divider on the transmit from the arduino and the esp8266 chip.
also the arduino will no reliably run at 57600 or 115200 baud.

Another thing worth the consider, is that arduino uno can only provide 50ma from its 3.3v pin, and the esp is rated at 300ma , so its not a wise idea to supply the voltage directly from the arduino board.

Hi All

This is my first post here, I have some experience in Arduino, but the ESP8266 is new for me.

The wiring is like it should on arduino, with no code loaded on it (bare minimum sketch- 9600baud). The only thing I get after powering the ESP is:
[Vendor:www.ai-thinker.com Version:0.9.2.4]

ready

sending AT or whatever is not doing anything. any idea?

Thx all!