Simple machine-to-machine communication

In the first project of this chapter, we are going to see a very simple case of M2M communication, where one ESP8266 Wi-Fi chip will send a trigger signal to another chip (via the cloud, of course), that will in response toggle the state of an LED. For the trigger, we'll use a simple push button connected to the first ESP8266.

Let's first assemble the hardware for this project. For the LED board, the hardware configuration is really easy: simply place the resistor in series with the LED, just as we already did in earlier chapters. Then, connect the resistor to pin 5 of the ESP8266, and the other pin to the ground.

This is the final result for the LED board:

For the board that will host the push button, first place the push button on the board, as well as the ESP8266. Then, connect the resistor to one side of the push button, and the other side of the resistor to the ground. Also connect pin 5 of this ESP8266 Wi-Fi chip to this side of the push button...