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Topic: Assistance with connecting ESP8266 to my arduino uno (Read 832 times) previous topic - next topic



I am trying to connect my ESP8266 serial wifi to my Arduino Uno and am having difficulties.  (I think this is the correct forum to ask this question.)   I am hoping someone with experience using the ESP8266 with an Uno can assist me.

I have an Arduino Uno, ESP8266 with an ESP01 adaptor.  At this point I am simply trying to get the ESP8266 to communicate with the serial monitor.  (I am not trying to flash the device.)

Here is my wiring:

Arduino    ESP8266
5V             VCC
gnd            gnd
TX 1           RX
RX 0           TX

My arduino is connected to my computer via USB.

I downloaded a BareMinimum sketch into the Arduino microprocessor.  At this point should I be able to see some signs of life from the ESP8266 using my Arduino serial monitor if set to "Both NL & CR" and with a baud rate of either 9600 or 115200?  I see nothing.

Thank you,


if you use the Uno board only as USB-to-TTL-Serial adapter, then wire RX to RX, TX to TX
(the pin labels are for the pins of the ATmega, which are wired to pins of the USB chip TX to RX)


Hi Juraj,
Thank you very much.  When I repositioned the RX and TX wires and typed "AT" I got an "OK".  This is a good sign.

I would like to know what BAUD rate the unit is currently operating at now.  (It is my understanding I can reset the baud rate by "flashing" the device.)  When I typed "AT+CIOBAUD?" I got an ERROR.  Do you know why this error occurred?

Again, thanks so much.


Be aware to use level converters where necassary, the Esp not 5 volt tolerant.


if you can communicate the baud rate is same as in Serial Monitor
the command is AT+UART?
to set the baud rate AT+UART_DEF=9600,8,1,0,0

it is 5 V tolerant for pull-up current levels


Thank you two for the help!
Best regards,

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