Category Archives: IDE

IDENTIFY ESDI DRIVE

Posted on May 25, 2022 by Michal Necasek

As previously mentioned on this site, the IDENTIFY DRIVE command in the ATA specification almost certainly first appeared in ESDI controllers supplied to Compaq by Western Digital. Since I have now finally secured a working ESDI hard disk, I could … Continue reading →

Posted in ESDI, IDE, PC hardware, PC history, Western Digital | 19 Comments

Vague Standards are Trouble

Posted on April 7, 2022 by Michal Necasek

Through the course of time I’ve been going over the IDENTIFY data of various old IDE hard disks. Today I happened to come across a Conner CP30254H drive, apparently made in June 1993 or so. This is a circa 250 … Continue reading →

Posted in Conner, IBM, IDE, PC history | 4 Comments

Another Trip to Drive Geometry Hell

Posted on January 24, 2022 by Michal Necasek

Recently I took another close look at the IDE.DSK driver in NetWare 3.12. Among other things, I wanted to know how it differs from ISADISK.DSK. On some systems, the two drivers are interchangeable and either will work. But there are … Continue reading →

Posted in IDE, NetWare, PC history | 8 Comments

First Dual-Channel IDE?

Posted on December 28, 2021 by Michal Necasek

The OS/2 Museum recently came into possession of what may be the first adapter with support for two IDE channels… sort of: The adapter was made by Plus Development Corporation, a subsidiary of the disk maker Quantum. This particular specimen … Continue reading →

Posted in IDE, PC hardware, PC history, Quantum | 29 Comments

Deeper Into ATA History

Posted on October 14, 2021 by Michal Necasek

While looking for something completely unrelated (namely the Rock Ridge extensions to ISO 9660), I came across a cache of old X3T9 committee documents from 1990. In retrospect I’m a little surprised that I hadn’t found these earlier, since the … Continue reading →

Posted in IDE, PC history, Standards | 17 Comments

The Dual-Drive IDE Hell

Posted on August 25, 2021 by Michal Necasek

I have perhaps inaccurate but very strong memories from my PC-building days (in the early to mid-1990s) that one of the most failure-prone and frustrating endeavors was trying to get two IDE drives working together on a single cable as … Continue reading →

Posted in IDE, PC hardware, PC history | 20 Comments

IDENTIFY Ancient DRIVE

Posted on July 22, 2021 by Michal Necasek

This article will attempt to collect IDENTIFY DRIVE dumps from antique IDE drives, with running commentary. For the purposes of this list, “antique” is defined as a drive model released in 1990 or earlier, typically with the drive itself also … Continue reading →

Posted in IDE, PC hardware, PC history, Storage | 9 Comments

Learn Something Old Every Day, Part II

Posted on July 17, 2021 by Michal Necasek

The ultimate reason why I pulled out the old Seagate ST-225 drive was because I wanted to try connecting it to the Western Digital WD1003-IWH board that I recently acquired. The WD1003-IWH is a curious evolutionary half-step between ST506 interface … Continue reading →

Posted in IDE, PC hardware, PC history, Storage | 11 Comments

Recalibration Needed

Posted on June 25, 2021 by Michal Necasek

The OS/2 Museum recently acquired two horribly slow old Western Digital IDE drives model WD93044-A. These were WD’s first foray into IDE hard disks, combining a rather outdated Tandon RLL drive chassis (3.5″ half-height stepper drives) with WD’s own controller … Continue reading →

Posted in Bugs, IDE, Western Digital | 32 Comments

Whence IDENTIFY DRIVE?

Posted on June 4, 2021 by Michal Necasek

As most everyone knows, the AT Attachment standard (informally known as IDE) started by literally bolting the previously standalone AT disk controller onto a MFM drive with a ST506 interface and connecting the assembly to the host system with a … Continue reading →

Posted in Compaq, Documentation, IDE, PC hardware, PC history, Storage | 36 Comments