Using an ideaspark development board, I will try to turn the onboard LED (GPIO2) ON/OFF every second. At the same time, I will output the status to the serial monitor. #include <Arduino.h> #define LED ...

It is a pretty common first project to use an Arduino (or similar) to blink an LED. Which, of course, brings taunts of: you could have used a 555! You can, of course, also use any sort of oscillator, ...