Author Archives: Michal Necasek

OS/2 6.304: Finally Complete

Posted on April 29, 2022 by Michal Necasek

Some time ago, I lamented that even though the OS/2 Museum had a good number of disks of the final OS/2 2.0 beta, level 6.304, there wasn’t enough to install the OS, let alone any of the development tools or … Continue reading →

Posted in CD-ROM, IBM, OS/2, PC history, Pre-release | 5 Comments

Page Too Big

Posted on April 22, 2022 by Michal Necasek

The other day I was able to look at an IBM OS/2 pre-release CD-ROM from early 1992. The CD-ROM appears to have been produced by IBM UK under the DAP (Developer Assistance Program) umbrella. The CD-ROM contains about 250 MB … Continue reading →

Posted in Documentation, IBM, OS/2, PC history | 4 Comments

Xenix 2.2 vs. VGA

Posted on April 15, 2022 by Michal Necasek

The other day I started wondering why certain old versions of 286 and 386 XENIX look a bit weird in emulation: The characters are cut off, because XENIX sets up an EGA text mode with 8×14 character matrix but uses … Continue reading →

Posted in 286, 386, PC architecture, PC history, VGA, Xenix | 14 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

FantasyLand on VGA

Posted on April 3, 2022 by Michal Necasek

In 1984, Joel Gould of IBM Cambridge (that is Cambridge, Massachusetts rather than Cambridge, UK) Scientific Center wrote a demo program named FantasyLand. This demo was meant to show off the capabilities of IBM’s brand new Enhanced Graphics Adapter, or … Continue reading →

Posted in IBM, PC hardware, PC history, VGA | 16 Comments

Reconstructing the EGA BIOS

Posted on March 19, 2022 by Michal Necasek

A few weeks ago I had a sudden need to understand certain finer points of the operation of EGA/VGA BIOS. I found common reference materials to be inadequate—they tend to do a good job of documenting the data structures the … Continue reading →

Posted in BIOS, Development, Documentation, Graphics, IBM, PC history | 32 Comments

Learn Something Old Every Day, Part IV: Ctrl+Scroll Lock is Ctrl+Break

Posted on February 26, 2022 by Michal Necasek

The other day I tried running NSNIPES, a multiplayer networked game that came with old versions of NetWare. The game worked fine, but I couldn’t get out of it. Esc did nothing, any “usual” combinations like Alt+X, Alt+Q or similar … Continue reading →

Posted in NetWare, PC architecture, PC history | 3 Comments

KEYBCS2

Posted on February 18, 2022 by Michal Necasek

After writing about the likely origins of IBM code page 852, I thought I should revisit the homegrown Czech alternative solution, the Kamenický brothers encoding and their keyboard driver. Its existence is well documented, and the so-called (somewhat misnamed) KEYBCS2 … Continue reading →

Posted in DOS, I18N, IBM, x86 | 29 Comments

Where Did CP852 Come From?

Posted on February 15, 2022 by Michal Necasek

In the 1990s, a lot of my documents were written in code page 852 (CP852), also known as PC Latin 2. This code page is sometimes called “Eastern European”, which is a bit misleading, given that it does not cover … Continue reading →

Posted in DOS, I18N, IBM, Microsoft, OS/2, PC history | 47 Comments

XMVM Surgery

Posted on February 11, 2022 by Michal Necasek

Last week I was prompted to take a look at the Intel Code Builder compiler from 1991, a 32-bit compiler targeting 386 extended DOS and shipping with its own DOS extender. It is what one might call an extremely obscure … Continue reading →

Posted in 386, Development, Intel, PC history, Software Hacks | 10 Comments