The origin of the phrases ATA and IDE [WAS:RE: formatting MFM drives on a IBM PC]

Tom Gardner t.gardner at
Sun Oct 1 14:46:16 CDT 2017

I've looked for but cannot find any WD or Compaq documents publically using IDE to describe what ultimately issued as ATA-1.  My search included various Compaq maintenance manuals.  The earliest public use of ATA and AT attachment that I can find is March 1969 at the CAM committee draft standard long before IDE was linuga franca for these drives.  The earliest public disclosure of the interface that I can find is revision IV to the Conner CP3022 specification dated Feb 1988; it doesn’t name the interface other than in terms of “task file emulation.”  It is likely that such documents existed from Conner prior to Feb 1988, perhaps as early as shipping the CP344 in 4Q86.  My point is the interface was public before it was named.


My recollection (possibly flawed) is WD tried to have the responsible committee change the name to IDE and failed.


I do have a confidential WD document from 1965 which does use the term IDE for "Integrated Drive Electronics" referring to their chips, a drive built with these chips was called an "Integrated Drive" or an ID.  


The earliest advertisements and specifications for what we would now call ATA-1 drives from Conner, MiniScribe and Quantum did not use either the term IDE or ATA.  I have a list of terms used if anyone cares.


As best I can tell WD began publically using the term IDE for its drives sometime around 1990 - if anyone can find a public usage prior to March 1989 of IDE to describe what became ATA-1  I'd really like to see it.


The CAM and ANSI committees have since March 1969 defined ATA == AT Attachment and NEVER used "Advanced Technology" as an acronym for AT in any standard or draft including the one cited below!  There are 134 possible definitions <>  of “AT,” including for example, “Appropriate Technology”  – sure the connection to IBM’s PC/AT  is obvious, but the authors, editors and reviewers of the standards never meant it to mean “Advanced Technology” so I suggest we respect their definition and not leap to an obvious but incorrect conclusion.




-----Original Message-----
From: Chuck Guzis [mailto:cclist at] 
Sent: Saturday, September 30, 2017 5:58 PM
To: Tom Gardner via cctalk
Subject: Re: formatting MFM drives on a IBM PC


On 09/30/2017 04:12 PM, Tom Gardner via cctalk wrote:

> I think Chuck has it backwards, AT Attachment as defined by the ANSI 

> committee publically predates IDE.  Although IDE was used internally 

> at WD it did not surface publically until well after the ANSI 

> committee adopted AT Attachment, abbreviated ATA.  The AT in AT 

> Attachment or ATA has never stood for "Advanced Technology" although many presume so.


"IDE" was a Western Digital term for drives used in the Compaq PC,

dating from 1986.   I've probably got documents from about that time

talking about IDE, if I look.   Because of Compaq's introduction of the

thing early on, that's what we called it then.


The "ATA Standard" began its work in 1988 by the Common Access Method committee of ANSI X3T10 and eventually came out with a standard in 1994, but that was long after "IDE" was the lingua franca term for these drives.  The ANSI document:




In, you'll read:


"The application environment for the AT Attachment Interface is any computer which uses an AT Bus or 40-pin ATA interface. The PC AT Bus is a widely used and implemented interface for which a variety of peripherals have been manufactured.  As a means of reducing size and cost, a class of products has emerged which embed the controller functionality in the drive.  These new products utilize the AT Bus fixed disk interface protocol, and a subset of the AT bus.  Because of their compatibility with existing AT hardware and software this interface quickly became a de facto industry standard."


So, even ANSI X3 talks about the PC AT bus.  And yes, "AT", according to IBM, stands for "Advanced Technology"


Pretty much, all you need to connect an ATA-1 drive to the 5170 bus is a couple of transceivers and an address decoder.




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