A handy use for DEBUG; and a standard that should be used!
- DEBUG and your Ports -

               Load DEBUG from DOS and enter the following command(s) at the "-" prompt:
                -D 40:0 L E    (NOT case sensitive)
           It will display the following information:

                0040:0000  F8 03   F8 02   E8 03   E802   -   78 03   78 02   BC 03

             This means:  COM   COM   COM   COM       LPT     LPT    LPT
                                        1           2           3            4              1           2        3

                Interrupt:      4           3            4           3              7          5         -

                The above shows all of the devices in use (unlikely), so the line could look something like:

                0049:0000  F8 03   00 00   00 00   0000   -    78 03   00 00   00 00

                                    COM                                              LPT
                                       1                                                      1

                This would be a more realistic view of what you would see... this is also a quick & dirty way
                to see what your BIOS thinks is in use.  Remember that these pairs are shown in reverse
                of the way we read them, so  F8 03 is really  3F8
                                                                                                                                                -Ted Mieske

Here is how to CLEAR an IDE Drive!
NO need to remove Partition(s) first.

        Here is another approach that won't touch the MBR; it just zero's out the drive. This is equivalent to a drive from the Factory:
                Load DEBUG from DOS and enter the following command(s) at the "-" prompt:
        (NOT case sensitive)

            -A CS:100  <enter>
            xxxx:0100   MOV AX,330      <enter>
           xxxx:0103    MOV CX,1        <enter>
           xxxx:0106    MOV DX,80     <enter>
           xxxx:0109    MOV BX,3800  <enter>
           xxxx:010C   MOV ES,BX      <enter>
           xxxx:010E   INT 13               <enter>
           xxxx:0110   INT 3                  <enter>
           xxxx:0111   <enter>
             -G  <enter>
             -Q  <enter>
                                                                                                                                              - unknown

Here is how to HOSE an IDE Drive when
you can't get rid of the Boot Record!

            (NOT case sensitive)

              -A CS:100   <enter>
           xxxx:0100     MOV   AX,301  <enter>
           xxxx:0103     MOV   BX,200  <enter>
           xxxx:0106     MOV   CX,1     <enter>
           xxxx:0109     MOV   DX,80   <enter>     ( 80=hd0   81=hd1   etc.)
           xxxx:010C     INT     13  <enter>
           xxxx:010E     INT     20  <enter>
           xxxx:0110     <enter>
                -G  <enter>
                -Q  <enter>
                Program should terminate normally.  If it DOES NOT, you entered something WRONG!
             NOTE: This will REMOVE all information from the Boot Record!!

             I have used this many times when a High-Level format would not work, or running FDISK or FDISK /MBR won't work!
            I know your told NOT to do this, but I have never had a problem with this trick when a drive just WON'T configure.

                                                                                                                                                - Ted Mieske

Need a copy of DEBUG?
This Version is from DOS v6.22

I'm BUGGED about 'DEBUG' Scripts!

     Why are we using .SCR for Debug Scripts?  This had been used in previous years for: Basic
   (CP/M) Source code, Screen shots, and Windows screen savers!  So I say, why not use .DBG?
    This has NEVER been used for anything, and it seems to be the logical choice!!  SO I say let's
 drop a lame extension that PC Magazine started in the '80's, and let's use a logical choice...your
input to zines WILL make a difference!

Copyright © 2000-2009  Ted J. Mieske
All Rights Reserved.