EEPROM - Arduino Sketches: Tools and Techniques for Programming Wizardry - page 101

CHAPTER
6
EEPROM
This chapter discusses the read() and write() functions of the EEPROM library.
The hardware needed to run the examples in this chapter are an Arduino Uno
and a USB cable.
You can i nd the code downloads for this chapter at http://www.wiley.com/
go/arduinosketches on the Download Code tab. The code is in the Chapter 6
download and the i lename is chapter6.ino .
Introducing EEPROM
Life would be boring if you had to reinstall software every time you turned
off your computer. In the beginning, that is almost exactly what happened. A
computer was turned on, and if a l oppy disk was not inserted, the computer
did not know what to do and just waited. It had no idea of who used it or what
programs were available. Ironically, little has changed; instead of a l oppy disk,
we have hard drives, storing many times more data, but it still relies on the
same principle.
Computers typically have two types of memory: volatile and nonvolatile.
Volatile memory contains data as long as it is powered. When the power is
removed, all the data is lost. This is how RAM works on your home computer.
It uses a memory module called DDR. Actually; DDR memory is even more