ESP8266

After testing the basic Wi-Fi connectivity options of the ESP8266 it is now time to explore some of the more interesting features of the chip. In the sketch below the NodeMCU development board creates a Wi-Fi access point and starts a web-server. A HTML page hosted on the web-server displays analog data from a photocell and allows you to control remotely a LED via Wi-Fi from a web-browser on your phone or PC. As in the previous examples, I am using the Arduino IDE to program the ESP8266 board. ...

Part 1 of this tutorial covers the set-up of the Arduino IDE to support the ESP8266 boards. In part 2 I will go through the steps of loading a slightly modified Blink sketch to the NodeMCU board. First, a couple of things to be aware of when working with the ESP8266 boards: Power: ESP8266 is a 3.3v board The NodeMCU version of the board has an on-board 3.3v voltage regulator and can be powered from the USB port (5V), or through the vin pin (5-7.5v recommended). All GPIO pins work at 3.3v and the board may be damaged, when connected directly to 5v Arduino compatible modules. Additionally, the maximum current that can be sourced from a digital pin is 12 mA. Use a high value resistor for LEDs (1k Ohm) and do not connect servos, motors, or other peripherals that draw large current. ...

I have recently started exploring an ESP8266 based development board I had sitting around. There is a growing number of firmware and development tools for the board, but as I am familiar with the Arduino IDE and syntax, I decided to give it a shot first. If you are familiar with Lua, you might be more comfortable checking out the NodeMCU project. Those guys created an open source hardware development board around the ESP8266 MCU with included USB interface for easy programming and power and custom firmware and development tool-chain to program the ESP8266 module using Lua. ...

ESP8266 Introduction The ESP8266 is a low cost MCU with built in Wi-Fi. It can be paired with another host microcontroller, like an Arduino, to provide WiFi networking capability for a basic IoT development platform. Additionally, the ESP8266 can be used as a stand-alone MCU, as it includes a 32-bit 80Mhz processor, 16 GPIO pins (4 PWM enabled) and a built in Analog-to-Digital converter, SPI and I2C interfaces and more… The MCU has a n operating voltage of 2.5V – 3.6V and average operating current of 80 mA. Here is the official ESP8266 MCU datasheet from the Shangai-based manufacturer of the chip Espressif Systems. The most popular current version is the ESP-12E MCU pictured below. On its own this is not very friendly for prototyping, as the spacing of the pins is not compatible with standard headers and breadboards. ...