Since some time, very cheap WLAN breakout boards with the SoC ESP8266 from China hits the market. Besides the possibility to extend your existing projects with WLAN (WiFi) access (eg. Arduino based ones) you can develop even simple Internet of Things applications without the need of an extra microcontroller.

Specifications:
- ESP8266EX SoC by Espressif Systems (32bit XTENSA LX Core)
- separate Flash memory chip (mostly 512kB)
- 3,3V – not 5V tolerant IO-Pins!
- max. 215mA (in sending mode +19,5 dBm / 802.11b, CCK 1Mbps) (only ESP8266 without other breakoutboard components)
- 802.11 b/g/n with integrated TCP/IP
- TKIP, WEP, WPA/WPA2 PSK, WPS
- WiFi Direct (P2P), Accesspoint (AP) and/or client mode
- SDIO 2.0, SPI, UART, I2S, PWM (different breakout board types!) – 12mA max. per IO-Port
- extern antenna, PCB antenna or ceramic-antenna (different breakoutboard types!)
- different firmware options, standard with AT commands over serial
- some breakout board types with different pin configurations
- own software with Espressif SDK, without other microprocessor
- also programmable with an extra Arduino IDE
Breakoutboard types overview (incomplete):
VCC (3,3V) and GND are additional to the pin lists below.
The pinout can be seen in the pictures – if available – (no responsibility is taken for the correctness of this information – boards with pictures are testet)!
ESP-01:
- 8 pins – 2,54mm pin distance
- RX, TX, CH_PD, GPIO0, GPIO2, RST
- PCB antenna
- dimensions: 24,8×14,2mm
ESP-02:
- 8 pins – 2,54mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO15, RST
- extern antenna over SMA adapter
- dimensions: 14,2×14.2mm
ESP-03:
- 14 pins – 2mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO12, GPIO13, GPIO15, GPIO16, CH_PD, WIFI_ANT
- ceramic antenna and/or over pin WIFI_ANT
- dimensions: 17,3×12.1mm
ESP-04:
- 14 pins – 2mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO12, GPIO13, GPIO15, GPIO16, CH_PD, WIFI_ANT
- extern antenna over pin WIFI_ANT
- dimensions: 14,7×12,1mm
ESP-05:
- 5 pins – 2,54mm pin distance
- RX, TX, RST
- extern antenna over SMA adapter
- dimensions: 14,2×14.2mm
ESP-06:
- 16 pins – surface mount
- extern antenna over pinout
- dimensions: 14,7×12,1mm
ESP-07:
- 16 pins – 2mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO4, GPIO5, GPIO12, GPIO13, GPIO14, GPIO15, GPIO16, ADC, CH_PD, RST, WIFI_ANT
- ceramic antenna and SMA adapter
- dimensions: 22,0×16,0mm
ESP-08:
- 16 pins – 2mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO4, GPIO5, GPIO12, GPIO13, GPIO14, GPIO15, GPIO16, ADC, CH_PD, RST
- dimensions: 17,0×16,0mm
ESP-11:
- 8 pins – 1,27mm Pinabstand
- RX, TX, GPIO0, GPIO1, CH_EN, RST
- PCB antenna
- dimensions: 24,0×16,0mm
ESP-12:
- 16 pins – 2mm pin distance
- RX, TX, GPIO0, GPIO2, GPIO4, GPIO5, GPIO12, GPIO13, GPIO14, GPIO15, GPIO16, ADC, CH_PD, RST
- PCB antenna
- dimensions: 24,0×16,0mm
Good?











