Beginning Arduino Programming

Hardware Interrupts

With an idea as to what functions can do for us, we can move on to a different kind of function—one that is driven by specific hardware in the microcontroller. The reasons for using interrupts are many; maybe we have a lot of code in our loop() function and sitting there waiting for a button press would slow things down too much or maybe we might even miss the button press all together. Or instead we might be using a photo sensor or interrupter that triggers when something gets close and it is important to stop a motor right at that exact time. These things are possible with a hardware interrupt that can be configured on one of two digital pins to trigger a unique kind of advanced function called an interrupt service routine ...