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As promised in comp.sys.cbm, here is Torquemada 1541. Because of its
programming and its intent to bang the #$%%! out of the drive head,
bear in mind THIS PROGRAM CAN CAUSE AS MUCH DAMAGE AS IT MIGHT REPAIR.
YOU USE THIS PROGRAM AT YOUR OWN RISK!

Torquemada 1541 is designed to attempt improving a drive's alignment
with multiple sequential seeks to the drive head's extents, as well as
intermittent BUMPs (slamming the drive head back). This can help with
sticky or uncooperative heads, and may make a drive functional enough to
read data without opening it up. It was written out of desperation when
three drives failed on me within a week, and to my disbelief, Torquemada
cured two of them (the other just had dirty heads). But your mileage
may vary!

An alignment master is ABSOLUTELY REQUIRED. This disk should be formatted
in God's Own Holy 1541 (i.e., a 1541 that's absolutely pristine with
perfect alignment), and it should be write-protected. Torquemada will use
this disk as its calibrated standard. I use the Epyx Vorpal Toolkit disk.

When you start, Torquemada will verify the firmware can respond properly,
and then prompt you for the alignment master and attempt to read it. The
program just makes sure the disk can be initialised, which may or may not
be enough to properly test drive function. You can ignore the warning that
the BAM is (now) readable and force bump'n'seek by typing Y at the prompt.
If the BAM is not readable, Torquemada will automatically start the
bump'n'seek cycle until it becomes readable.

Four cycles of seek 35/bump/seek 1 are run, and then the BAM is rechecked.
On an older 1541, this can cause quite a racket -- this is normal (?). Repeat
as desired. Hold the space bar to cancel a run or quit.

For those interested in how the program works, the subroutine at line 5500
is a general purpose FDC job code dispatcher. See "Inside Commodore DOS" for
an excellent explanation of the process. Some other goodies include proper
values for REVCNT (set to no bumps/no seeks before reading BAM to ensure the
cleanest read possible, and set to max bumps/seeks during bump'n'seek to
give the drive head the most vicious workout possible), and using the write
protect sensor to check for the presence of a disk or tab.

This program is not designed for clone 1541s, 1581s or CMD FDs, and because
1571s rarely go out of alignment, the program offers a special warning to
remind you (which you can, of course, ignore).

This program is also not designed to replace proper alignment with tools and
elbow grease, but as a temporary quick fix to get a drive in working order
quickly. Remember, the head impact techniques used can potentially make a bad
alignment problem worse -- use this program ONLY AS A LAST RESORT, before
opening the drive and aligning it manually.

Cameron Kaiser