The REFSTAMP utility
====================

Overview
--------
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's 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!

Using REFSTAMP
--------------
The program is most simply invoked with a single parameter; this
specifies the drive containing the disk to be 'stamped', e.g.:

          REFSTAMP A:

Normally, a copy of the original, 'unstamped' boot sector is saved in a
file named REFSTAMP.SAV, on the same disk.  It is possible to restore
the original disk state by invoking REFSTAMP with the /R option:

          REFSTAMP A: /R

This will also delete the REFSTAMP.SAV file.  To suppress the creation
of REFSTAMP.SAV in the first place, use the /N option:

          REFSTAMP A: /N

To avoid accidental overwriting of REFSTAMP.SAV, the program will refuse
to 'stamp' a disk that already has the right 'signature'. 

Bob Eager
September 1999
rde@tavi.co.uk
http://www.tavi.co.uk/ps2pages/