Category Archives: PC history

EXEPACK and the A20-Gate

Posted on March 23, 2018 by Michal Necasek

In 1991, DOS 5.0 brought about what’s perhaps the most common manifestation of A20 control trouble… Packed file is corrupt Microsoft published a KB article about this infamous error, but its author clearly did not understand the true cause of the … Continue reading →

Posted in Bugs, Microsoft, PC history | 19 Comments

The A20-Gate: It Wasn’t WordStar

Posted on March 16, 2018 by Michal Necasek

Although WordStar was long suspected to be the reason (or at least one of the major reasons) for implementing the A20 gate hardware on the PC/AT and all the associated problems later on, it is now all but certain that … Continue reading →

Posted in 286, IBM, Microsoft, PC history, WordStar | 37 Comments

Pascal Out Of Memory

Posted on February 23, 2018 by Michal Necasek

Suppose you want to run the original 1981 vintage IBM Pascal 1.0 (supplied by Microsoft) on a PC that is less than 30 years old. Upon execution, PAS1.EXE may well fail with the following error: Error: Compiler Out Of Memory … Continue reading →

Posted in Bugs, Corrections, IBM, Microsoft, PC history | 40 Comments

WordStar Again

Posted on January 26, 2018 by Michal Necasek

While trying to work on my DOS 5.0 article, I looked at DOS 5.0 build 224 from June 1990, which is the oldest surviving beta of DOS 5.0. And the README contains the following intriguing text, which reminded me of … Continue reading →

Posted in DOS, PC history, WordStar | 74 Comments

DOS 5: TMI

Posted on January 19, 2018 by Michal Necasek

For several years now I’ve been trying to continue the DOS history series and write (or rather finish) a DOS 5 page. While tracing the history of DOS 1.0 or 2.0 is quite difficult and the amount of source material … Continue reading →

Posted in DOS, PC history, Random Thoughts | 14 Comments

About That Warranty…

Posted on January 19, 2018 by Michal Necasek

Readers have been wondering what kind of valuable warranty users of Microsoft’s Quick Pascal 1.0 (and other products) might be voiding by running it on top of DR DOS 3.3x or 3.40. I don’t have the original Quick Pascal 1.0 … Continue reading →

Posted in Digital Research, Microsoft, PC history, Undocumented | 16 Comments

How Apple Created Hackintosh, Part II

Posted on December 20, 2017 by Michal Necasek

There is every indication that throughout the early 2000s, Apple internally built and ran all of OS X on x86 PCs (it’s also something Steve Jobs himself mentioned in 2005). Otherwise why would Apple have x86 drivers for AC’97 audio … Continue reading →

Posted in Apple, Intel, OS X, PC history, Pre-release | 10 Comments

How Apple Created Hackintosh, Part I

Posted on November 29, 2017 by Michal Necasek

At a developer conference in June 2005, Apple announced that OS X will transition from PowerPC to Intel processors. The first Intel Macs (sometimes nicknamed “Mactels”) were introduced several months later, in January 2006. The announcement generated significant interest in … Continue reading →

Posted in Apple, Intel, PC history, Pre-release | 10 Comments

MS KB Articles

Posted on October 17, 2017 by Michal Necasek

A recent blog post over at pcjs.org explores some of the mysteries surrounding information that at one point or another was published as a Microsoft KnowledgeBase article (or a KB article for short). It’s not entirely clear where the KB … Continue reading →

Posted in Documentation, Microsoft, PC history | 17 Comments

Audio Frequency Data Acquisition

Posted on August 23, 2017 by Michal Necasek

Readers of this blog may have noticed that besides OS/2 software, I have interested in PC sound cards. I thought I had a decent idea about the major milestones in PC sound history, but I had to perform a few … Continue reading →

Posted in IBM, MCA, PC hardware, PC history, PS/2, Sound, Sound Blaster | 17 Comments