The REFSTAMP Utility

Most users of PS/2s will know that reference disks (and certain other maintenance-related disks) have a special property. This property is that they will, barring a major misconfiguration, always boot even if the machine has a configuration or other problem which results in error codes being displayed on power-up or reboot.

This special property is not provided in a very magic way; the BIOS simply looks for three particular bytes that make up a 'signature' in the boot sector of the disk. If these three bytes are found, in the right place, the disk will boot despite any POST errors. As a bonus, if you have a reference partition on the hard disk, you will find that for the duration of that boot, your reference partition will appear as drive C:. This provides a good way of deleting unwanted files without going to the trouble of restoring the reference partition from the original disks.

It is quite useful to be able to 'stamp' a disk with this signature. One reason might be that you are making a utility disk which you want bootable at all times (such as a disk containing IDMCA). Another might be that the 'signature' has been destroyed (this can happen even if you just look at the disk under Windows).

The traditional way of placing the 'signature' on a disk is by using the DOS utility DEBUG. However, this may not be available, and its use is somewhat error prone. REFSTAMP is a utility whose sole purpose is to add that signature to a disk; it touches nothing else on the disk except those three bytes. It is also very small, so it will fit on a disk of emergency tools!

The program can preserve the original boot sector in a file on the disk being altered, and restore its original state if required. It can also report the current state of a disk (i.e. whether or not it has the signature on it).


Content created and/or collected by:
Louis Ohland, Peter Wendt, William Walsh, Kevin Bowling, Jim Shorney, Tim Clarke, David Beem, Tatsuo Sunagawa, Tomáš Slavotínek, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 11 Apr 2021 - Changes & Credits | Legal Info & Contact