The ESP8266 WiFi Module is a self-contained SOC with integrated TCP/IP protocol stack that can give any microcontroller access to your WiFi network. The ESP8266 is capable of either hosting an application or offloading all Wi-Fi networking functions from another application processor. Each ESP8266 module comes pre-programmed with an AT command set firmware, meaning, you can simply hook this up to your Arduino device and get about as much WiFi-ability as a WiFi Shield offers (and that’s just out of the box)! The ESP8266 module is an extremely cost-effective board with a huge, and ever-growing, community.

Features:

• 802.11 b/g/n • Integrated low power 32-bit MCU •
Integrated 10-bit ADC •
Integrated TCP/IP protocol stack •
Integrated TR switch, balun, LNA, power amplifier and matching network •
Integrated PLL, regulators, and power management units •
Supports antenna diversity • Wi-Fi 2.4 GHz, support WPA/WPA2 •
Support STA/AP/STA+AP operation modes •
Support Smart Link Function for both Android and iOS devices •
Support Smart Link Function for both Android and iOS devices • SDIO 2.0, (H) SPI, UART, I2C, I2S, IRDA, PWM, GPIO
 • Deep sleep power <10uA, Power down leakage current < 5uA
•Wake up and transmit packets in < 2ms • Standby power consumption of < 1.0mW (DTIM3)
• +20dBm output power in 802.11b mode
• Operating temperature range -40C ~ 125C

Espressif ESP-8266: minimal configuration for running the ESP-12e module

I am working on a project where I haven't quite decided on some of the details, so I wanted a module that breaks out a lot of the ESP8266's pins, just to have as many options available as possible.


The ESP-12e module seems like a good choice, with the added benefit of having 4MBytes of flash memory.

Odd stuff

A few things are a bit odd about these modules:

• The silkscreen is a very poor print quality
• The ADC pin is labelled ADG
• The GPIO labels are a mess. Eg: There is no GPIO0 (this is labelled GPIO6 instead)

Where's GPOI0?

Todo: try flashing LEDs on all GPIOs to compare against NodeMCUs IO table

Basic configuration

So after a little experimentation, this turned out the most basic configuration:

Basic config for ESP-12e

I plan to run this without a circuit board, so I'll simply shorten GPOI15 to ground and connect the "chip Power Down" Pin (ch_PD) to 3.3V. 

The Module came preinstalled with some AT-firmware, I didn't much care about.

Flashing new firmware

To program new firmware, GPOI0 (which for some reason is GPIO6 here) needs to be connected to ground. I am a huge fan of NodeMCU, so I flashed that to the module.

Ground GPIO6 (=GPIO0) to flash firmware via UART

This goes without saying

Connecting the serial-USB converter is unspectacular. Just the usual RXD-TXD / TXD-RXD thing. And don't forget to connect the ground wires.

Connecting the USB2Serial converter