Many of the programs using this scheme are checking the
      protection with simple drive commands and the kernal routines in
      the computer ROM. Keep in mind that this check can be done with
      Basic programming as well as machine language. Once understood,
      most are fairly easy to unprotect.
      
      Most of the time the programmer will check for the bad sector
      with a block read. It will look something like this: U1:aa bb cc
      dd, or B-R:aa bb cc dd. The aa denotes channel, bb denotes drive
      number, cc denote track, and dd denotes sector. A character or two
      is then returned from the drive, and a comparison is made. If the
      comparison is satisfactory, the program continues operation. If
      not, the program flow is ended or set in an endless loop. Our task
      will be to either give the program the proper characters, or to
      short circuit the program flow around the protection check.
      
      Before starting to work on any of the following programs, please
      do a disk log, an error scan, noting all write errors, and make a
      C-64 Fast Copier backup which will remove all errors. Place a write
      protect on the original disk.
      
      
      
                         TAPPER : BALLY NIDWAY
      
      Procedure:
      
      Loading the original produces a drive rattle twice. An error
      scan shows write errors on the original. A backup made with Three
      Minute Backup produces a non-working copy. Before starting to work
      on this program, make two backup copies.
      
      Working with your backup:
      
      1) In order to look at the boot with our monitor, we must change
         its location in memory. The reason for this is because this boot
         cannot be stopped once it has been started. This is a simple
         procedure. From your utility disk, load DISK DR <> LOAD"DISK
         DR",8,l <>. When the cursor reappears type RUN and hit RETURN.
         Remove the utility disk and insert one of your Tapper backups in
         the drive. Hit RETURN again and you will be shown Track 18,
         Sector 1. Cursor over to position 3 and hit the J key. This will
         take you to the first sector of the Boot file. The first four
         bytes in this sector are the pointer bytes. Bytes 0 and 1 are
         the pointers denoting this as the only sector and the number of
         bytes used in this sector. Bytes 2 and 3 are the program address
         bytes in reverse order.  Place the cursor over the byte in
         position 2 and hit the @ key. Now, type a 1 and hit RETURN. The
         cursor should now be on position 3. Again hit the @ key and type
         an 8 and hit RETURN. To make the changes on the backup, hit the
      
            K.J. REVEALED TRILOGY    PAGE [4]      (C)1990 K.J.P.B.