IDE->INTEGRATED DRIVE ELECTRONICS

IDE CONTROLLER WORKS

Most personal computers have one or more of the following storage devices:

• Floppy drive
• Hard drive
• CD-ROM drive

Usually, these devices connect to the computer through an Integrated Drive Electronics (IDE) interface. Essentially, an IDE interface is a standard way for a storage device to connect to a computer. IDE is actually not the true technical name for the interface standard. The original name, AT Attachment (ATA), signified that the interface was initially developed for the IBM AT computer. In this article, you will learn about the evolution of IDE/ATA, what the pinouts are and exactly what "slave" and "master" mean in IDE. 

The Integrated Drive Electronics interface is the most popular way to connect a hard drive to a PC.

Drives that use the interface officially known as AT Attachment or ATA are also often called something else entirely: Integrated Drive Electronics or IDE drives. In fact, the term "IDE" is probably more widely used than the correct name for the interface! (This is changing, however, as new terms such as "Ultra ATA" grow in popularity.) IDE can be considered the unofficial "overall name" for this hard disk interface; it has been used since the earliest days of these drives, and will probably always be used by a large segment of the industry.

The reason for the name, of course, is that the IDE interface was the first where the logic board was integrated on the hard disk itself. As described in some detail in the overview and history of the interface, drives prior to this point had the hard drive control logic on a separate controller card that plugged in a system bus slot. This led to a number of compatibility and reliability problems that were corrected by mating the logic board to the hard disk itself.

The name "IDE" really reflects this design decision and has nothing to do with the interface per se. Today, all drives have integrated logic boards, including those that use interfaces quite different from ATA, such as SCSI or USB. However, habits are hard to break in the computer world, and use of the name persists. This has the potential for confusion, though most people today know that "IDE" refers to the IDE/ATA interface specifically. (One of the reasons that the name "IDE" was never adopted for the formal standards is that the developers of the standards considered it confusing.)

It's important to remember that today, being told that a particular drive is an "IDE drive" tells you only that it uses some variant of the IDE/ATA interface. "IDE" by itself is a generic term that does not tell you anything about the drive, such as what modes it supports or what official standard it adheres to. You need to find out more about the drive to understand the details of its interface.

Posted in: Hardware and Networking