How to Program ESP8266 (ESP-01) Module with Arduino UNO

Last Updated on August 25, 2022 by technoreview85

Esp 8266 01 is a popular wifi module.
It can works with AT commands with an Arduino. Also, it can be used as a standalone board like a microcontroller.

esp 8266 01 module — Esp 8266 – 01 Wifi module

Its working voltage is 3.3v & it is very small in size so we can easily make our IoT based project using it.

It is a guide for programming the esp 01 module using an Arduino Uno board with Arduino ide software, sample led blink code & also discuss about some errors & its solution while programming.

How to connect esp8266 – 01 to Arduino Uno for programming

We have to connect the Esp 01 to Arduino Uno. You can make a temporary set-up on a breadboard. but you can’t use it directly on a breadboard so you have to use jumper wires. some times it is the reason for connection error.

I made a shield for Arduino for avoiding every time jumper wire connection so making shield is a better option for programming every time without any problem.

Connection

Esp 01 arduino wiring — connection diagram

The Tx pin of Esp 01 connects to TX of Arduino Rx to Rx of Arduino.

Push switch connects to reset pin & GND pin of Esp 01.

Connect ChPD & VCC & connect to 3.3 volt of Arduino.

Connect ESP 01 GND to Arduino GND

The SPDT switch is connected to GPIO 0, Led + & GND.

To enable flash mode you have to connect Gpio 0 to GND so here I am using a switch to enable flash mode & working mode. This Led is for an indication.

And Arduino Rest pin connect to GND.

You need to make a shield

Male & female header pins
LED
Dotted board
Micro push Switch
Small SPDT switch
ESP 01 module
& Arduino Uno board

Programming Setup on Arduino IDE

Open Arduino Ide, go to – File – preference – paste this additional board
Manager URL.

http://arduino.esp8266.com/stable/package_esp8266com_index.json

Click – ok
Now go to tools – Board – Board manager – search for Esp 8266.
I have already installed the board version 2.5.1 & it is working fine So I am not going to update it. You have to install it & then click on close.

Now connect the ESP 01 & Arduino to computer make sure the switch is on flash mode. If you have made a temporary setup then make sure GPIO 0 is connected to GND.

Now go to tools – select board generic Esp 8266 Module.

Go to tools – select your com port where Arduino is connected

Uploading sample LED blink code to ESP 01

Goto file – Example – Esp 8266 – Blink

Change this built in to 0 .
Our LED is connected to GPIO 0

Now click on upload you can see the code is uploading
& complete.

Now change the switch position & push this reset button once.

Error during programming Esp8266 01 module

Sometimes it shows some connection error.

Solving the problems

1 check your connections
2 chek proper com port
3 chek gpio 0 is connected to GND
4 press the reset button once before showing connecting.
5 use a 220mfd electrolytic capacitor on VCC & GND of ESP 01.