Category Archives: Debugging

Tracking Down a Bug

When I first encountered the Unix vi editor many years ago, I recoiled in horror. It was nothing like the editors I was used to—Borland IDEs, DOS 5.0/6.x EDIT, or OS/2 and Windows editors. But over the years, I learned … Continue reading

Posted in Debugging, Development, DOS, Watcom | 14 Comments

Win16 Retro Development

Several months ago I had a go at producing a high resolution 256-color driver for Windows 3.1. The effort was successful but is not yet complete. Along the way I re-learned many things I had forgotten, and learned several new … Continue reading

Posted in Debugging, Development, Microsoft, Windows | 25 Comments

LAN Manager 2.1/2.2 Registration

Anyone who spent a bit of time archiving software distributed on floppies probably knows this situation: There’s only one disk set of a given software release known to exist, and it’s not clean. That is, it’s been previously used to … Continue reading

Posted in Archiving, Debugging, Microsoft, Software Hacks | 18 Comments

Can This Conner Talk?

As part of research into the IDENTIFY DRIVE command, the OS/2 Museum acquired two old Conner IDE drives, a CP-342 and a CP-341i. These drives look extremely similar at first glance, and they’re both 40 MB IDE drives, but on … Continue reading

Posted in Conner, Debugging, Hardware Hacks, Storage | 19 Comments

WD1007V Commands

While researching material for a previous article, I wanted to examine the only AT-compatible ESDI controller I have, a Western Digital WD1007V-SE2. My board was made in 1990, the firmware is from 1989, and the controller was likely introduced in … Continue reading

Posted in Debugging, Documentation, ESDI, Western Digital | 3 Comments

Booting Windows XP, Or Not

For a number of years now I’ve been using a SATA SSD with a “portable” Windows XP installation on it. Portable in the sense that it was capable of booting on a number of my machines, either in IDE mode … Continue reading

Posted in Debugging, PC hardware, Windows XP | 16 Comments

ANOMALY: meaningless REX prefix used

While trying to get work done, I was confronted by several disturbing messages printed on the console of a 64-bit Windows 7 system: [0x7FEEFEFAAA0] ANOMALY: meaningless REX prefix used [0x7FEEFEE48C0]¬†ANOMALY: meaningless REX prefix used [0x7FEEFEE54B0]¬†ANOMALY: meaningless REX prefix used This … Continue reading

Posted in Bugs, Debugging | 9 Comments


This might save someone a bit of head scratching… Several times, I tried to install Windows NT Advanced Server (NT 3.1 server) straight from CD-ROM (well, ISO) into a clean VM. The installation failed every time, asking for a nonexistent … Continue reading

Posted in Debugging, NT | 33 Comments

Solaris 7 Boot Panic

On some systems, it has been observed that Solaris 7 panics during boot from installation media and reboots the system. At least Solaris 7 U1 (3/99) and U4 (11/99) are affected. Only “fast” systems (definitely including Sandy Bridge 3+ GHz … Continue reading

Posted in Bugs, Debugging, Solaris | 6 Comments

Periscope Manuals

Some time ago I recovered a latter-day Periscope manual from storage. Since some readers might find it useful, I decided to scan the manual and convert it to PDF. It covers the basic Periscope debugger, variants and add-ons (remote Periscope, … Continue reading

Posted in Debugging, Documentation | 7 Comments