Author Archives: Michal Necasek

IBM ThinkPad Power Series 850

In the mid-1990s, IBM and Motorola unsuccessfully tried to create a new personal computer platform built around PowerPC RISC processors. Apple was initially a member of the alliance called AIM (Apple/IBM/Motorola) and used PowerPC processors in its own Macintosh systems … Continue reading

Posted in IBM, PowerPC | 48 Comments

Ctrl-Alt-Del Myths

In a recent interview at Harvard University, Bill Gates claimed (around 16:35 mark) that Windows uses Ctrl-Alt-Del as a logon key combination because “IBM didn’t want to give [Microsoft] a single button”. This statement is curious because it takes several facts … Continue reading

Posted in Microsoft, PC hardware | 8 Comments

Taking Screenshots of OS/2 on ThinkPad 850

An article about OS/2 on a PowerPC-based ThinkPad 850 needed a few screenshots for illustration. Once an OS is installed and running a GUI, it’s typically possible to run a screen grab utility and capture screenshots digitally. But that’s not an … Continue reading

Posted in OS/2, PowerPC | 4 Comments

OS/2 on ThinkPad 850

The ThinkPad 850 was no ordinary ThinkPad. It was IBM’s high-end portable multimedia workstation, built around a 100MHz PowerPC 603e processor, with a list price of $12,399 (February 1996). The ThinkPad 850 was originally slated (see IBM announcement letter 195-176) to … Continue reading

Posted in IBM, OS/2, PowerPC | 18 Comments

The Central Point Backup Floppy Format

A reader recently asked about the “native” format of Central Point Backup (CP Backup) floppies. Diskettes formatted in this manner are somewhat tricky to work with as they do not use a standard DOS format. A session with Sydex’s AnaDisk … Continue reading

Posted in DOS, Floppies | 28 Comments

Kids these days…

By sheer accident I stumbled on this document. In summary, it’s about a bunch of school kids working on a computer history preservation project and trying to archive a big box of floppies from George Alistair Sanger, a video game … Continue reading

Posted in DOS, Floppies | 22 Comments

The XDF Diskette Format

In 1994, IBM started shipping software with support for XDF, or eXtended Density Format, first in OS/2 Warp and a few months later in PC DOS 7.0. Some of IBM’s software packages were also distributed on XDF diskettes. XDF allowed … Continue reading

Posted in Floppies, IBM | 24 Comments

Why Won’t IBM’s MSPS201.SYS Load?

Recently a minor mystery resurfaced. When IBM’s OS/2 1.2 SE is installed on any “normal” system (either physical or virtual) and the PS/2 mouse driver is installed (the typical choice), the mouse won’t work: The MSPS201.SYS driver is intended for … Continue reading

Posted in IBM, OS/2 | 8 Comments

Detecting Floppy Drives and Media

Detecting floppy drive types and installed media is a far trickier topic than it should have been. In the ideal world, software could determine how many floppy drives are attached, what their capabilities are, and what media is installed in … Continue reading

Posted in Floppies, IBM, PC hardware | 18 Comments

Detecting an Empty Drive… Or Not

Detecting an empty drive with a NEC uPD765A or compatible FDC is theoretically easy using the ‘drive ready’ signal. In practice, the drive ready mechanism is completely unusable on IBM PCs and compatibles due to the way the FDC is … Continue reading

Posted in OS/2, PC hardware | 16 Comments