cc-05@cory.Berkeley.EDU (Joe Good) (02/28/88)
I have a simple question for all you Apple users out there. It was recently suggested that a computer virus infecting an IBM system had somehow managed to overwrite write-protected disks. I always thought that write protection was a hardware as well as a software protection, and therefore could not be circumvented. My question is this: Can you write on a write protected disk on an Apple, and if so, how? I tried reprogramming the DOS that sensed the write protect, and the drive attempted to write on the disk, but couldn't. I am expecting about 50 replies of "just punch out the write protect!", but I would appreciate any real attempted responses, even if they are negative. You can either mail me or post here, as I'll stay subscribed for a little while to find out. Thanks. ------------------------------------------------------------------------------- Joe "BD" Good, President, BRS movie reviews... ... "We owe it to the brain of our species to stand here and die!" ... just when you thought it was safe to get back in the shower... Mildew Man!!! cc-05@cory.berkeley.edu should work as an address...
malex@cory.Berkeley.EDU (Michael Alexander) (02/28/88)
The write protect is in the hardware, so to try and reprogram the DOS will not work. If you really want to write to a write protected disk, you can break off the notch in the drive itself. This will never sense a write protected disk, hence always writing. I wouldn't suggest this, because the write protect is just what it says: Protection. But, since you asked, that is the scoop.
spike@bu-cs.BU.EDU (Spike) (02/29/88)
In article <1068@pasteur.Berkeley.Edu> cc-05@cory.Berkeley.EDU.UUCP (Joe Good) writes: > My question is this: Can you write on a write protected disk on an <Apple, and if so, how? I tried reprogramming the DOS that sensed the >write protect, and the drive attempted to write on the disk, but <couldn't. An the answer is... Hardware. The write protect is done by the hardward and thus patching DOS will not help. In Disk ][s you can open the drive and loosen the screw (or was it a hex nut?) that holds the 'feeler' of the write protect sensor. The 'feeler' should drop down a bit so that it will be under the disk and therefor disabled. Just push it up and tighten it when you are done. In newer drives (and the //c) a light sensor is used so this will not work. You can, however do a little wiring and make a switch so you can have Normal, Write Always, Read Only mode. Send me mail if you want more details. "Last night I had that dream again. I dreamt I had to take a test, in a Dairy Queen, on another planet." UUCP: ...!harvard!bu-cs!bu-it!spike ARPANET: spike@bu-it.bu.edu CSNET: spike%bu-it@bu-cs BITNET: engemnc@bostonu "VPS sucks" -- ->Spike
medin@cod.NOSC.MIL (Ted Medin) (02/29/88)
In article <1081@pasteur.Berkeley.Edu> malex@cory.Berkeley.EDU.UUCP (Michael Alexander) writes: >The write protect is in the hardware, so to try and reprogram the DOS will >not work. If you really want to write to a write protected disk, you can >break off the notch in the drive itself. This will never sense a write >protected disk, hence always writing. I wouldn't suggest this, because >the write protect is just what it says: Protection. But, since you asked, >that is the scoop. I have a problem with a flakey //e. Prodos wont let me write on a diskette because its write protected (it isnt) but i can use copy //+ to copy files and diettes on the same machine with out any problems. Got any ideas???????
mccarthy@well.UUCP (Patrick McCarthy) (03/02/88)
Regarding writing to write-protected disks, as far as I know, there is *NO WAY* to write to a write protected disk on an unmodified Apple (or totally Apple compatible) drive (also assuming that the drive itself isn't blown up). There is a simple modification you can make to apple-compatible drives to make them ignore write protection (I've done this to my second drive), and one of the most common hardware flames will cause an Apple drive to wipe track 0 clean, write protect or no, but other than that... I'm also not totally convinced that write protection can be software ovveridden on IBM machines, either, but I wouldn't bet my paycheck on it. Pat McCarthy mccarthy@well.uucp
koko@oldhub.toronto.edu (M. Kokodyniak) (03/02/88)
Write protection on the Apple II+ is done by software. The state of the write-protect microswitch is read directly by DOS.
mw22+@andrew.cmu.edu (Michael Alan Wertheim) (03/02/88)
I'm not sure about 3.5-inch drives, but with 5.25-inch drives the write-protect mechanism is in the hardware. You can tell DOS or ProDOS to ignore the write-protect, but it still won't be able to write on the disk. Michael Wertheim Carnegie Mellon University Pittsburgh, PA Arpa: mw22@andrew.cmu.edu Bitnet: mw22@cmuccvma