Category Archives: IBM

IBM XENIX: Two Steps Forward

Posted on March 16, 2017 by Michal Necasek

There are reasons to revisit an old topic. Very old, considering that IBM Xenix 1.0 was released in 1984, well over 30 years ago. To recap, this version of Xenix is unique in that it runs only on 286 processors. It … Continue reading →

Posted in 286, IBM, VirtualBox, Xenix | 22 Comments

Deskpro 386 at 30

Posted on September 26, 2016 by Michal Necasek

30 years ago, in September 1986, Compaq announced the Deskpro 386, a PC as revolutionary as it was conservative. Compaq decided to forge its own path and not wait for IBM to introduce a 386-based PC. At the same time, Compaq … Continue reading →

Posted in 386, Compaq, IBM, PC history, PC press | 19 Comments

More Wobbles

Posted on August 24, 2016 by Michal Necasek

This is a follow-up to a previous post. I’ve had a chance to spend more time recovering the two dead PS/2 Model 80s. The first step was replacing the CMOS batteries because without a functioning backup battery, a PS/2 is … Continue reading →

Posted in Floppies, IBM, PS/2 | 10 Comments

Wobbly Floppy Drive?

Posted on July 12, 2016 by Michal Necasek

Over the weekend I tried to revive a PS/2 Model 80 whose CMOS battery died (after 25 years!). Finding a replacement battery fortunately isn’t difficult (6V lithium “photo” battery), but recreating the configuration information of course requires a reference floppy and … Continue reading →

Posted in Floppies, IBM, Plug and Play, PS/2 | 30 Comments

IBM OS/2 1.x Programming Documentation Added

Posted on April 15, 2016 by Michal Necasek

IBM’s programming documentation (Programming Tools and Information, aka PTI) for OS/2 versions 1.2 and 1.3 has been added. Big thanks to Bob Eager who scanned the originals and converted them to PDF. The documents have been added to the OS/2 … Continue reading →

Posted in Development, Documentation, IBM, OS/2 | 2 Comments

Playing Football

Posted on February 19, 2016 by Michal Necasek

The Super Bowl is long over and it’s time to look at different kind of football. In Winter 1986/1987, Microsoft initiated a small skunkworks project called “Football”. The objective was to take “Sizzle”, a development branch of proto-OS/2 that would eventually … Continue reading →

Posted in 386, IBM, Microsoft, OS/2, PC history | 21 Comments

Before OS/2 Was OS/2

Posted on February 5, 2016 by Michal Necasek

After almost 30 years, several disks with ancient builds of OS/2 surfaced. In this context, “ancient” means older than the May 1987 release of the first MS OS/2 SDK. In fact these disks are so old that the one thing … Continue reading →

Posted in IBM, Microsoft, OS/2, PC history, Undocumented | 39 Comments

More ISA VGA Benchmarks

Posted on November 6, 2015 by Michal Necasek

After establishing that Trident VGA cards are indeed very slow, the natural follow-up question is: Are there cards even slower than that? But not some 8-bit VGA card from the 1980s (or a Realtek from the 1990s), and not some … Continue reading →

Posted in Cirrus Logic, IBM, S3, VGA | 9 Comments

IBM XENIX: One Step Forward, One Step Back

Posted on March 29, 2015 by Michal Necasek

A while ago I wrote about why IBM PC XENIX 1.0 can’t work on any CPU other than a 286. But not content to leave well enough alone, I attempted to patch this version of XENIX so that it would … Continue reading →

Posted in 286, 386, IBM, VirtualBox, Xenix | 5 Comments

The DOS 4.0 Shell Mouse Mystery

Posted on March 21, 2015 by Michal Necasek

Several years ago, I noticed that in some virtual and physical environments, the DOS Shell in both IBM’s and Microsoft’s DOS 4.0x has a very odd glitch: the mouse pointer moves, but does not register any clicks… except on scroll … Continue reading →

Posted in DOS, IBM, PC hardware, PC history | 28 Comments