Tool to test arbitrary disk surfaces

[schmidtd <schmidtd@my-deja.com>]

I was looking for a tool to do disk surface stress testing of
arbitrary disks (not necessarily just floppies) and didn't come up
with anything beyond testers for the 5-1/4" drive.  Rich Dreher had
asked me to do long-run stress testing on the filesystems supported by
his new CFFA3000 card.  I needed to fill some time on vacation anyway,
so I went ahead and cooked a simple one up.  And so SPF (Stress ProDOS
Filesystem) was born.

I hacked up the ADTPro platform to offer services to do ProDOS
formatting of volumes, and what I call low-level testing of volumes.
The low-level test goes as follows:

0) Pick a volume to test, answer a couple of "are you sure's"
1) Write $AA to all bytes of the volume via WriteBlock calls
2) Read back all bytes a block at a time, verify $AA is there
3) Keep a count of write/read/verify loops
4) Repeat steps 1-2 with byte $55
5) Repeat indefinitely, or until you hit escape

If it encounters any errors (ProDOS read, write, or comparison) the
last one it hits is left on the screen.  The idea is that it writes
alternating pattens of 10101010 and 01010101, and verifies that every
bit makes a transition and is verified in both states on the disk
"surface."

Just so we're clear, this is a destructive test - if I were smarter,
or more careful, I could probably stash the block I was writing/
reading/verifying, then put it back when done.  But I'm not.

In case anyone but me is ever interested in such a thing... it's
available on Asimov:
ftp://ftp.apple.asimov.net/pub/apple_II/images/disk_utils/StressProDOSFileSystem_001.zip