Learn how calculators work by making your own with Arduino

Although at first glance, you might think "Why would I make my own calculator?" ... but why not? One of the great benefits of the Arduino platform is the ability to recreate various devices - and during that process, gain a much deeper understanding of how they work. 

An interesting example of this has been published by Don van der Drift, who shows us how to make a simple calculator with some inexpensive parts.

Don uses a common 16-button numeric keypad, and we really like how he has simplified reading the keypad by using resistors across various outputs so the whole thing can be read by one analog input.