The ESP8266 is a small development board that includes a MOD-WIFI-ESP8266-DEV board in a socket, a 250V AC / 10A relay (RAS-0515), a button, a UEXT connector, and a 0.1″-pitch header connector with all ESP8266 signals.

The board must be powered by a regulated 5V supply via its 2.5mm barrel jack. Please see the Powering the Board notes below.

A strip of pin headers is included loose for you to solder to the GPIO header pads if desired.

The button has two uses. It's usually a general-purpose button, but if it's pressed during power up the ESP8266 will go into bootloader mode so you can upload new firmware to the chip. To upload code you will need any USB-to-serial 3.3V converter like the USB-SERIAL-CABLE-F (which you can add using the option checkbox at the bottom of this page). You can plug the leads of that cable into the appropriate UEXT pins of this board.

If you use the new Arduino IDE for ESP8266 released recently, with this board you can have an Arduino-driven WiFi device that is faster and cheaper than an official Arduino board by itself — which doesn't even have WiFi built in!

Espressif ESP8266 Features

• 802.11 b/g/n
• Wi-Fi Direct (P2P), soft-AP
• Integrated TCP/IP protocol stack
• Integrated RF switch, balun, LNA, 24dBm power amplifier and matching network
• Integrated PLLs, regulators, DCXO and power management units
• +19.5dBm output power in 802.11b mode
• Power down leakage current of less than 10µA
• Integrated low-power 32-bit CPU could be used as application processor
• SDIO 1.1/2.0, SPI, UART
• STBC, 1×1 MIMO, 2×1 MIMO
• A-MPDU & A-MSDU aggregation & 0.4ms guard interval
• Wake up and transmit packets in less than 2ms
• Standby power consumption of less than 1.0mW (DTIM3)
• Integrated RISC processor, on-chip memory and external memory interfaces
• Integrated MAC/baseband processors
• Quality of Service management
• I2S interface for high-fidelity audio applications
• On-chip low-dropout linear regulators for all internal supplies
• Proprietary spurious-free clock generation architecture
• Integrated WEP, TKIP, AES, and WAPI engines

Add-on UEXT Modules Available

Powering the Board

ESP8266 Development Board Resources

• ESP8266-EVB Schematic
• ESP8266-EVB Design Files for Eagle
• How to set Flash/UART/SDIO mode on MOD-WIFI-ESP8266-DEV module
• ESP8266 Documentation (refers specifically to a reference design)
• Espressif Systems ESP8266 Datasheet
• ESP8266 Community Forum — includes section about Arduino IDE for ESP8266
• ESP8266 Community Wiki
• Espressif Forum with software and SDK downloads, AT command set, etc.
• Espressif GitHub Page (may not be as up to date as the forum)
• Olimex ESP8266 GitHub Page has more tools and examples; the IoT Firmware implements a JSON-based web server client and includes support for the following UEXT modules: MOD-RGB, MOD-TC-MK2-31855, MOD-IO2, MOD-IRDA+, MOD-LED8x8RGB, and MOD-RFID125-BOX, as well as SNS-FINGERPRINT