Contents of the CHGTYPE.DOC file
This program installs a new drive table for the ST1144A for
systems that don't have a BIOS that allows a user defined drive
type. The drive type was defined as a type 45 which has the same
number of heads, and sectors/track that we want, just not enough
cylinders. Drive type 9 should also work. The only other thing
changed was the landing zone to make it the last cylinder. This
program should run as the first thing in your AUTOEXEC.BAT file.
Loading it before any SET commands will reduce the environment
size and save a few bytes of memory. The same holds true for any
TSR -- they all should be loaded before SET commands to save
First set the drive type to 45. Don't attempt a low level format
on an ST1144A, you will destroy the bad track information. It is
already low level formated at the factory. Next do an FDISK and
set up drive the bootable drive -- drive C:. Don't do the
extended DOS partition just yet. Format C: and transfer the
system to it with:
FORMAT C: /S
Add a /V for volume label if you desire. Make a DOS directory
and transfer your DOS files to it. Then create your CONFIG.SYS
and AUTOEXEC.BAT files. The first line in your AUTOEXEC.BAT file
should run CHGTYPE. Put it in the any directory you desire but
if it is not in the root directory of C:, add the drive and path
to it. Once this is done, boot the system. Now run FDISK again
and it should know you have 1000 cylinders (it starts counting a
zero so will be one less than the 1,001 you told it). Now create
the extended DOS partition and create drives D: - F:. Now format
these drives and drive F: should be 29 megs. That's all there is
While this method should work with other drives as well as long
as the number of cylinders are the only thing different, I don't
guarantee it (in fact I don't anyway).
Mapmem says this table it taking 160 bytes of memory on my system.
This method should work on drives other than the ST1144A as long
as you can define a drive type that only the number of cylinders
need to be changed. I am including the source code along with
CHGTYPE. You can modify it and reassemble if you have an
assembler or use debug to modify the table if you don't have one.
Use this program at your own risk! It is working fine on my
system for me with the ST1144A but you are on your own should you
decide to use this program.