You can download our e-book ‘Learn Arduino’ from this link

Introduction

The Internet of Things is a relatively new concept in the world of electronics. It was also quite expensive and maybe even unreachable by some hobbyists. The introduction of the ESP8266 changed that perception forever. Being first designed as a simple Serial WiFi adapter; today it is the most common IoT device among electronic hobbyists and hackers alike. The ESP is cheap, small, powerful and easy to program as you shall see in a jiffy. This tutorial will focus on the ESP-01 model.

There are many versions and different boards with the ESP8266, in this tutorial we will focus on the most common and cheapest model the ESP-01. This little board comes pre-installed with the original firmware which allows it to act as a Serial WiFi Module, however, this firmware is of little use to us. Together we are going through the process of transforming a WiFi Module into a fully flagged stand alone WiFi enabled Arduino.

First and foremost it is very important to note that the ESP8266 is not 5V tolerant. VCC and all other pins must be fed 3.3V only. Apart from that the ESP-01 cannot be programmed directly because it does not have a USB port and is not even RS232 compatible. We will need an FTDI 3.3V like the one below.

Now all you need are some jumper wires to connect the ESP with the FTDI.

Connections

• ESP-01          FTDI
• VCC                  VCC (remember 3.3V only)
• GND                GND
• RX                    TX
• TX                    RX
• CH_PD           VCC
• GPIO 0           GND (only used to flash the module with new software)

Done that, grab a USB cable and plug it in the FTDI and your PC.

Environment Setup

Prerequisites: Latest Arduino IDE ( link )

• Start Arduino IDE
• Go to File > Preferences.
• Enter http://arduino.esp8266.com/stable/package_esp8266com_index.json in Additional Board Manager URLs field. You can add multiple URLs, separating them with commas.
• Open Boards Manager from Tools > Board menu and find esp8266 platform.
• Select the latest version
• Click install button.
• Go to Tool > Boards and select Generic ESP8266

Testing

All set and ready to code. Make sure your ESP is plugged in. Go to Tools > Port and select the COM port which the ESP is connected to. Then paste the code below. It’s a simple blink program to test our setup.

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the LED_BUILTIN pin as an output
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (Note that LOW is the voltage level
                                    // but actually the LED is on; this is because 
                                    // it is active low on the ESP-01)
  delay(1000);                      // Wait for a second
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH
  delay(2000);                      // Wait for two seconds (to demonstrate the active low LED)
}

If the LED blinks, you’re done. The setup is complete and you can start experimenting with your ESP-01. Stay tuned for Part 2 of this tutorial 🙂