In this post I will show you how to flash your ESP-01 and upload a NodeMCU firmware. In order to do that we will need to setup our development kit.

ESP8266 ESP-01 is a $2 Wifi module, a Microcontroller and a chip with full TCP/IP stack. This hardware is quite old now, but still useful if you want to create some small automation projects.

NodeMCU is an open-source firmware that helps to update your LUA code on your ESP8266. It also embedded a lot of functionalities : MQTT, DHT, PWM, TELNET, GPIO, etc.

ESP8266 ESP-01 Flashing kit

1. Requirements

You can buy the following items on Aliexpress :

2. Let's build our flasher kit

For this example , I will always use the same cable color.

2.1 ESP-01 - Pinout

ESP8266 ESP-01 Pinout

First thing to do is to connect each colored item on the above image with jumpers .

To connect the jumpers with the picture above, I am using two stackable female header. It's easier to plug and unplug your ESP-01 without rewiring everything.

2.2 Breadboard

Plug your FT232RL in your breadboard and your power Supply as shown, then, wire your ESP-01 to the FT232RL.

To enable flash mode, we need to plug GPIO 0 to the GND. You won't need it after when we are going to upload our first program.

Do not forget to plug ESP-01 RXD output to FT232RL TXD input and ESP-01 TXD to FT232RL RXD!

NodeMCU firmware download

2.3 Test it

If you click on your Power Supply white button, your ESP8266 red LED will light. It means you plug it correctly !

Good! You're now ready to flash it ;)

3. Download NodeMCU Firmware

On NodeMCU Github you can download a master or dev firmware. For this example, we are going to use the dev firmware.

Download the firmware here

NodeMCU firmware download

4. ESPTool

For Mac OSX and Linux users, we will use ESPTool.
For Windows users : NodeMCU Flasher

4.1 Installation

pip install esptool


You can do it manually and download the files from Github.

4.2 Flash it

You're now ready to flash it. Switch on your power supply and connect your FT232RL to your computer.

NodeMCU ready to flash it

If you install ESPTool manually :

cd esptool


sudo python2.7 -p /dev/cu.usbserial-A900beEX write_flash 0x000000 nodemcu_builds_dev/nodemcu-dev-8-modules-2016-04-19-19-17-49-float.bin


  • My device is connected to /dev/cu.usbserial-A900beEX. To see your FT232TL, you can easily "ls /dev/cu".
  • Write address is 0x000000
  • The binary I want to upload is nodemcu-dev-8-modules-2016-04-19-19-17-49-float.bin

If everything works as expected, no error will occur :
ESPTool works

Congratulations! You're now ready to write your first program and upload it to your ESP8266.

Next time I'll show you how to write your first program in LUA and how to upload it. If you do not want to wait until my next post. You can use ESPlorer to upload your program.


ESP8266 Official website :
NodeMCU :
ESPTool :
ESP8266 :