partitioning with debug

If you’ve ever decided to use a ‘new’ pc for some old OS’s or whatnot, you’ll probably find partition tables that will NOT clear under MS-DOS…

Well after looking around for a ‘quick’ and easy method of wiping a partition table, I found this neat little script for DEBUG to do the trick….

Don’t try it out on any machines you care about…!

Debug Enter Debug Comments
Prompts Commands
– A 100 Assemble from CS:0100.

nnnn:0100 INT 13 Call interrupt 13.

nnnn:0102 press the (nnnn in the segment address).

– RAX Replace AX register.

AX 0000

: 0301 Write on sector.

– RBX Replace BX register.

BX 0000

: 0200 Start from ES:200.

– F 200 L 200 0 We want to write zeros.

– RCX Replace CX register.

CX 0000

: 0001 Cylinder, 0, sector 1.

– RDX Replace DX register.

DX 0000

: 0080 First physical hard disk, head
0. (Substitute 0081 for this
entry if you are clearing the
table on the second physical
hard disk, 0082 if you are
clearing the third physical
hard disk, and so forth).

– P Proceed (Debug will display
several lines of information).

– Q Quit Debug.

This entry was posted in MS-DOS, partition tables by neozeed. Bookmark the permalink.

About neozeed

What is there to tell? I’ve loved UNIX like things since I was first exposed to QNX in highschool (we had the Unisys ICONS!), and spent the better time of my teenage years trying to get my own UNIX… I should have bought Coherent in retrospect.. Anyways latched onto Linux in 1992, and then got some old BSD admin books and have been hooked on the VAX BSD & other big/ancient things since…!

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