Apple /// stuff (was: Re: This weekend's haul)

On Wed, 25 Jun 1997, Doug Spence wrote: I've been really lucky in that respect. All my disks seem to be working fine even after 10 years (tap on silicon). I still even have my first two Dysan floppies that my friend gave me for my computer class in 9th grade. Haven't booted them in a while though. I know of a way to fix bad sectors on Apple // disks that requires a little luck. I wrote a sector editor a long time ago that I used for all my hacking. This editor allowed me to read and write sectors very easily. I disabled the checksum verification in DOS so that when it came upon a bad sector it wouldn't barf. It would just read whatever data it found and then throw it up on the screen. I could tell if a sector wasn't right by the look of its bytes in ASCII with relation to sectors around it. I got very good at this. Whenever I found a bad sector on one of my disks, I would run my sector editor, jump to the bad sector then continually read it until I saw what I liked and then wrote it back out. Worked like a charm. This would usually fix the problem, which was caused by acute bit rot. This obviously won't work on disks that have just plum gone bad, but I've had a phenomanol (shit can't spell today) success rate. If anyone wants to do this, you stick an $18 in $B942 (from the monitor B942: 18) which disables the DOS sector checksum verification. Of course you must use a sector editor which uses the DOS in memory. Sam ------------------------------------------------------------------------------- Computer Historian, Programmer, Musician, Philosopher, Athlete, Writer, Jackass