BB
                                    --
          Documentation for version 2.0, on September 11th, 1991

                              by Bruno Costa



WARNING

  Although  this  program  is freely distributable (see COPYRIGHT below), I
would  appreciate  if  you  take the time to write me a line or two (E-Mail
please)  if  you  are  using  any of my programs or if you have any kind of
ideas  or  suggestions  (This is not too much to ask, is it?).  If you feel
particularly  generous,  I  would  like  to  receive a disk with any useful
programs you have written, preferrably with source.  Thanks!


DESCRIPTION

  BB  is a multi-purpose small utility to manipulate Amiga floppy disk boot
blocks.  Besides being able to read, write, show and install bootblocks, BB
has a couple of unusual features.  It is able to fix the bootblock checksum
of  a  disk, so that you may be able to write your own bootblocks or modify
existing  ones  and  keep them bootable.  It is also able to insert a small
preamble in existing bootblocks that will put the Fatter Agnus in PAL mode,
so  that any programs - including Workbench and even most heavily protected
games - will believe to be running in a PAL machine, with the corresponding
PAL  display.   If  you have any European applications, games or demos that
boot from floppies, this is certainly the easiest way to automatically boot
them in PAL mode.

  BB  is  also useful to install custom bootblocks you have written, and to
backup  bootblocks  to  files, so that if your disks become infected with a
bootblock  virus,  you  will be able to restore the original bootblock from
your backups. It works both under WB1.3 and WB2.0.


OPTIONS

  usage: bb [-acshpd] [-i<filename>] [-r<filename>] <drivename>

  BB  can  operate  in  only  one  of  the following modes, selected by the
respective option:

  i =  install new bootblock.  The given filename is read, and installed in
  the selected drive, with a correct checksum.

  d =  install a DOS bootblock.  An 1.3 standard bootblock is installed  in
  the selected drive, with a correct checksum.

  r = read bootblock.  Reads the bootblock from disk and writes it verbatim
  to  the  given file.  Note that the whole bootblock is written (including
  the header), i.e., a total of 1024 bytes.

  c =  fix  checksum.  Fixes the checksum of the bootblock on  the selected
  drive.

  s =  show bootblock.  Prints the printable characters in the bootblock in
  ASCII format to standard output.

  p =  adds  PAL  booter.   Adds  a  small  PAL  preamble  to the  existing
  bootblock.   Note  that  this may not work with some bootblocks, so it is
  advisable  to  backup the bootblock to a file using the 'r' option.  Note
  also  that  this preamble does not work with an Agnus chip older than the
  Fatter (it will simply boot in NTSC in this case).

  In  any of these modes, an 'a' option may be used to make the program ask
for a disk insertion before proceeding.  This is mostly useful to owners of
single drive systems.

  A drivename may be specified either as "df1:", "DF1:" or simply "1".


EXAMPLES

  To install a PAL booter in df0:, with a prompt for disk insertion:

  > BB -ap 0
  Please insert disk in DF0: and press ENTER ...
  warning: this may make your bootblock unusable!
           remove disk or press ENTER to continue:

  To backup a bootblock to a file:

  > BB -rdh0:bblocks/diska.bb df0:

  To restore that bootblock to the disk:

  > BB -idh0:bblocks/diska.bb df0:

  To show the contents of a bootblock in drive df1:

  > BB df1:


BUGS

  PAL booter does not always work.

  This  kind of program is perfect to be a trojan horse type virus, but you
have the full source code so that you can assure it isn't.


AUTHOR

  The  accompanying  program  and  this documentation were written by Bruno
Costa.  He can be reached in the following ways:

  E-Mail: bruno@brlncc.bitnet (InterNet)
          bruno@BRLNCC        (BitNet)

  Mail:   Bruno Costa
          Rua Almirante Guilhem 454/102 bloco 1
          Leblon - Rio de Janeiro
          RJ 22440
          BRAZIL


COPYRIGHT

  This program is copyrighted by Bruno Costa.  It may be freely distributed
if  and  only if the source code, the documentation and the executables are
provided  in  original form.  It may be included in Public Domain/Shareware
compilations,  like  the  one  organized  by  Fred  Fish, as long as just a
nominal fee is charged for each disk (no more than US$10 per disk), and may
also be uploaded to BBS's or network services like BIX and CompuServe.


DISCLAIMER

  The author makes no warranty of any kind with respect to this product and
explicitly  disclaims  any implied warranties of merchantability or fitness
for  any  particular  purpose.