Monthly Archives: August 2013

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 | 21 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 | 7 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 | 10 Comments