ESP8826 programming using Arduino Uno as FTDI breakout:

Hello forum!

I'm trying to use my Arduino as a programmer for the ESP8266 module but it doesn't really seem to work. When I choose the correct port (The port that says "COM3 (Arduino Uno)") in the Arduino software and open the Serial Monitor it doesn't output anything at all.

I removed the ATMega328P from the Arduino, and plugged RESET into GND.
I connected the wires like this: (NOTE: I have tried to switch around the tx and rx cables lots of times)

ESP8266 - TX -> Arduino TX (pin 1)
ESP8266 - RX -> Arduino RX (pin 0)
ESP8266 - CH_PD -> 3.3v (Ext)
ESP8266 - VCC -> 3.3v (Ext)
ESP8266 - GND -> GND (Ext)

The only thing the ESP8266 does is sit there with the little lit red power led. The blue led is not blinking unless i switch around the RX and TX pins. Then it's lit up constantly.

I just want to see som output from the ESP8266 and be able to send commands to it from the serial monitor in the arduino software. But all the Serial Monitor shows is a blank white screen...

Hope someone can help me with problem as i want to build cool things this summer aswell :slight_smile:

Did you set the line ending of the Serial Monitor to "Both NL & CR"?
Did you connect the grounds?
Did you pull up GPIO0 and RST?
Are you sure that you have the AT firmware installed?

You might be interested in my Beginner's guide to the ESP8266.


For just a few dollars, I don't know why people refuse to buy a proper USB-TTL adapter to communicate with their ESP8266 module.

In addition, a good 3.3V power supply capable of providing 1 A max is also important to have.

For just a few dollars, I don’t know why people refuse to buy a proper USB-TTL adapter to communicate with their ESP8266 module.


I really like these red FT232RL modules. You can find them all over Ebay etc. for around $1.80. You can easily switch between 5V and 3.3V (without accidentally hitting a switch and blowing up your 3.3V chip) and if you solder some male headers to it, you can fit it on a breadboard, and you have access to both RTS and DTR, allowing for easy auto-reset of the ESP8266.

So I’d definitely recommend to get one of those, but while you wait for it to arrive, you can use an Arduino as USB-TTL adapter.

I’ve used an RS232-TTL adapter, a Teensy 3.2, and an Arduino Leonardo to program it, but I’ve never tried an Uno.