Nano + esp8266-01

Forgive bad English.I am using an arduino nano and a esp 01 as wifi shield. I know that there are several topics here and everything but I have tested them all and none of them worked, I also tested the most diverse physical links and also all of the same error. the code compiles porem when I open the serial port at the time that connect the esp does not connect to the wifi … I do not know what can be …I tested all the schemas I found on the net. but I used as the code blynk suggests, rx, tx (pin 2, 3)


And yet others do eventually get this combo to work…

Not sure what more we can do to assist… anything and everything that can be suggested has been in all the other topics. This really shouldn’t need to be run through yet again.

  • Separate 3.3v, 800mA - 1A power for ESP… share the GND with the Arduino. Be sure you have 3.3v to both the VCC (pin8) & CH_PD (pin 4) pins on the ESP-01

  • Always cross the RX from one device with the TX on the other, visa versa. (e.g. from mouth to ear between to people)

  • Use a TTL-USB adapter to first confirm or flash a recent AT firmware to the ESP-01, and preset it for 9600 BAUD if using SoftSerial



  • NOTE that the Arduino’s designated TX pin is at 5v level… and may or may not damage (or even just confuse) the ESP-01’s RX pin, which only expects 3.3v Use level shifter, voltage divider or take your chances.

  • In most cases the designated RX & TX pins used on the Arduino are NOT the actual silkscreened RX/TX pins (depending on board type). Generally one uses Softserial on the Arduino UNO & Nano. Pick your digital pins according to the availability on the device, and confirm they are assigned properly in the sketch.


  • When using SoftSerial, use only 9600 BAUD for best results with Blynk. And again, make sure you have pre-programmed the ESP-01 (with AT commands) for the same 9600 BAUD

  • Load a test script onto the Arduino, set the Softserial pins and BAUD rate properly for your Hardware. NOTE: Default sketch is preset for Hardware Serial, using Serial1 for Mega, Leonardo, Micro… and uses built in Serial for IDE serial monitor… these default configs will NOT work for UNO, Nano… adjust as required for SoftSerial.

// Hardware Serial on Mega, Leonardo, Micro...
// #define EspSerial Serial1

// or Software Serial on Uno, Nano...
#include <SoftwareSerial.h>
SoftwareSerial EspSerial(2, 3); // these are the alternate RX, TX pins used on the Arduino (DON'T use the silk screened RX/TX ones)

// Your ESP8266 baud rate:
#define ESP8266_BAUD 9600
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