ATAPI, also known as Advanced Technology Attachment with Packet Interface, is the standard type of connection that keeps everything in your computer connected to each other. This article will go over all of the different functions of ATA and ATAPI, how it works, devices that use ATAPI, upgraded versions of ATAPI, and competing technologies.


ATAPI is a newer version of the old ATA (Advanced Technology Attachment) connection. Where as ATA was exclusively designed for connecting hard drives to the motherboard, ATAPI is made to connect all portable devices to your motherboard including RAM, hard drives, CD-ROMs, DVD drives, and other devices. ATA and ATAPI were invented by Western Digital and the standard is maintained by X3/INCITS Committee. Western Digital was also the first to create Integrated Drive Electronics (IDE), which was the forerunner of ATA. In 2003, ATA was further upgraded to Serial Advanced Technology Attachment (SATA) and has since been dubbed Parallel ATA. IDE is the main connection in your computer where as ATAPI provides the commands that allow IDE to work with newer devices. ATAPI is included in the wide array of connections and technology known as EIDE (Enhanced Integrated Drive Electronics).

How ATAPI Works

ATAPI cables are made up of 40 separate wires that end in 40 slots on either in that are used to plug into the device on one end and the computer on the other end. Electrical output is transmitted from the device through these wires and into the CPU (central processing unit) where it is converted to information. Naturally, information can also be sent from the CPU to the device. It is a simple idea but time has shown a great struggle in perfecting these wires and improving them over the years to be more accessible and reliable and to make them transfer information faster than ever before. We’ll go over the various upgrades of ATAPI later on.

Devices That Use ATAPI

If you have ever opened up your desktop computer to add an extra hard drive, you already know what ATAPI is. ATAPI is the cable that you plug into your hard drive(s). It usually has at least two connections on it: Drive 0 for the master drive and Drive 1 for the slave drive. Your ATAPI cable may be slightly different and include a Drive 2 or even Drive 3 but the basic structure is the same. The ATAPI cable is also used for your floppy drive and CD-ROM drive. ATAPI cables can be used for a wide variety of devices but most other devices have switched to more modern cable systems such as Firewire or USB to be used externally.


To understand how ATAPI has been upgraded over the years, you must first get a grasp of how the technology started out. First, we had IDE which was then broadened to EIDE. IDE started off using ATA but was then upgraded to ATAPI. ATAPI itself has been through five main versions but the whole system went through IDE, ATA 1, ATA 2, ATA 3, ATAPI 4, ATAPI 5, ATAPI 6, ATAPI 7, and ATAPI 8. ATAPI was then upgraded further to SATA and eSATA, which we’ll go over later. IDE and ATA 1 were considered breakthrough technology at the time but looking back, it still had a lot of improvements to look forward to.

Competing Software & Technologies

Like everything else, many technologies have come out to compete with ATAPI over the years and it becomes up to the manufacturer of what type of connection they are going to include in their computers. Below are a few examples of competing software and hardware that have been introduced to the market.


SATA (Serial Advanced Technology Attachment) is similar to ATA but it has a few major differences. For one, ATA required long cables with many pins to transfer information. SATA, on the other hand, brings this requirement down to seven pins and uses less cable. SATA also brought about the use of “hot swapping” and “hot plugging” which basically just means that you can unplug the device while the computer is still in operation. The “serial” part of SATA means that information is sent over the wires one bit at a time where as the previous PATA version (Parallel Advanced Technology Attachment) transferred information two bits at a time. While PATA may seem better, it requires more cables and equipment. Eventually, other technologies made SATA a better choice than PATA. ESATA (External Serial Advanced Technology Attachment) is the same thing as SATA but made for external use.


USB is probably a more familiar name to you than IDE, ATA, PATA, SATA, or eSATA. While USB has been used for less time than any of these older technologies, it has proved to be a very popular connection method. Many input devices for your computer such as mouses and keyboards now come accessible with USB and many other popular devices such as external hard drives and cameras use USB as well. Some devices such as electronic cigarettes and cell phones can even be charged by plugging a specially adapted charger into your computer’s USB ports.


Firewire is basically the same thing as USB but is made exclusively by Apple. Firewire has been included in all of the latest Mac PC models and the Ipod. Firewire strives to be one of the fastest connection methods in the computer industry and is incredibly efficient at pushing large amounts of information through cables in a very short time span.