What is NodeMCU?

The NodeMCU development board is a powerful solution to program microcontrollers and be part of the Internet of Things (IoT). The NodeMCU development board, based on ESP8266EX, is a cute module with a microcontroller, integrated Wi-Fi receiver, and transmitter. NodeMCU supports several programing languages; hence, it is very easy to upload programs from any computer over a micro-USB port. I have been playing with the NodeMCU for quite a while now and, I have to say, it is a lot more fun than the other available IoT modules. When it comes to prototyping — just another perfect, relatively cheap, easy-to-learn, and user-friendly minuscule magic module!



Categories Items Parameters
Protocols 802.11 b/g/n
Frequency Range 2.4G~2.5G (2400M~2483.5M)
Hardware MCU Xtensa L106
Flash 4MB
Peripheral Interface UART/SDIO/SPI/I2C/I2S/IR Remote Control
Power Supply 4.5V~9V(10VMAX),Support USB power supply
Operating Voltage 3.0~3.6V
Operating Current Average: 80mA(200mA MAX)
Standby Current <200uA
Transmission Rate 110-460800bps
Port Driving Capability 15mA
Operating Temperature Range -40℃~+125℃
Storage Temperature Range -40℃~+125℃
Board Size 48mm x 26mm
Weight ~7g
Software Wi-Fi Mode Station/SoftAP/SoftAP+Station
Security WPA/WPA2
Encryption WEP/TKIP/AES
Firmware Upgrade

UART Download/OTA (via network)

Download and Write Firmware via Host


Supports Cloud Server Development/

SDK for Custom Firmware Development

Network Protocols IPv4,TCP/UDP/HTTP/FTP
User Configuration AT Instruction Set,Cloud Server,Android/iOS App

Pin Definition


Note:D0(GPIO16) can only be used as GPIO read/write,no interrupt supported no pwm/i2c/ow supported.

You can see the new GPIO map as below:

IO index ESP8266 pin IO index ESP8266 pin
0 [*] GPIO16 7 GPIO13
1 GPIO4 8 GPIO15
3 GPIO0 10 GPIO1
4 GPIO2 11 GPIO9
5 GPIO14 12 GPIO10
6 GPIO12

Micro USB port – it use for upload the program and update firmware,you can also charge the battery
Reset button – to have a reset
Flash button – it use for update the firmware

Hardware Resource

The NodeMCU is a  fully open–source hardware,you can get more informations at below links:

hardware Resource:

Getting  Started with the Osoyoo NodeMCU Kit

Tutorial and sample projects(Arduino IDE)


You can list you question here or contact with [email protected] for technology support.

When I connect stuff to some of the pins, the NodeMCU stops working. Whats up with that?

The ESP8266 uses some of the pins as ‘boot mode’ pins so on boot they must be set to certain values:

My NodeMCU board keeps crashing and resetting, whats up with that?

The most common reason for crashes is power failure. Make sure you’re powering the NodeMCU with a good ~5V power supply, and if you’re using a USB-Serial cable, that its plugged into the mainboard of your computer or through a powered hub!

I can’t seem to find the Serial port on my computer for the NodeMCU?

Don’t forget to install the Serial port driver(CP2104 driver / CH340 driver) or your computer, they are required!

 I can’t get Lua to respond to my commands

Make sure your terminal software is sending correct line endings! The default PuTTY settings may be wrong when trying to talk to Lua on an ESP8266. Lua expects CRLF “\r\n” line endings, and apparently PuTTY defaults to just LF “\n”!


ESP8266 Datasheet & Other Documents:


NodeMCU office website:

NodeMCU Documentation:

Windows flash tool:

Linux flash tool:

ESPlorer GUI: