Re: Disk ][ Drives not working

[Don Bruder <dakidd@sonic.net>]

In article <zLKdna9c6uBl-n7d4p2dnA@comcast.com>,
 "Bill Garber" <willy46pa@comcast DOT net> wrote:

> "Don Bruder" <dakidd@sonic.net> wrote in message
> news:JoJEc.19790$Fo4.263681@typhoon.sonic.net...
> : In article <pan.2004.06.30.23.17.16.824452@alirossdotco.uk>,
> :  Alistair J Ross <mailat@alirossdotco.uk> wrote:
> :
> : > Hello again,
> : >
> : >     Thank you to all of you lovely people who offered to send
> me a disk with
> : >     DOS 3.3 in my recent problem of chicken-and-egg: getting
> DOS to my Apple
> : >     ][ Europlus.
> : >
> : >     Well. I have now recieved said copies of software (thank
> you very *VERY*
> : >     much), so I went about booting the disks (I have two
> copies of the DOS
> : >     master disk, just in case). Unfortunately, the ][ just
> sits there on
> : >     startup with APPLE ][ on screen. Drive 1 moves the head
> back to the rear
> : >     of
> : >     the drive (if not already there) and it tries to move
> it's self back even
> : >     further (is this called calibrating?!) - in doing so, the
> drive gives out
> : >     a
> : >     (what I would call) slightly irregular thud, thud, thud
> sound. About 10
> : >     or
> : >     so of these thuds and the drive head ceases to move
> against it's stopper.
> : >     The drive motor continues to run however, until I hit
> RESET.
> : >
> : >     Both of my drives perform the same issue when they are
> set to be Drive 1.
> : >     I
> : >     have 2 Drive ][ controller cards which both do the same
> thing. I have
> : >     stripped the drive of it's casing to see exactly what is
> happening but
> : >     everything (with exception of the heads simply moving
> back to the rear of
> : >     the drive and hitting against the stopper repeatedly) is
> normal. There
> : >     are
> : >     no immediate signs of wear and I have ran a non-abrasive
> head cleaner
> : >     through the drive just in case.
> : >
> : >     If I manually push the heads to the front of the drive,
> then the drive
> : >     first of all pushes the heads to the back again, before
> resuming the
> : >     normal
> : >     thudding, so it seems to know that its got to go back to
> the bottom to
> : >     seek
> : >     for something.
> : >
> : >     Anyone any ideas as to why this is happening? Should I
> shell out the 20
> : >     or
> : >     so pounds on Ebay to buy a couple of new drives? I don't
> really think
> : >     there
> : >     is that much wrong with these drives. Do you?
> : >
> : > As always, many thanks in advance.
> : >
> : >     Alistair Ross
> :
> :
> : You're describing a drive that's not seeing any startup code on
> the
> : disk. The next thing to wonder is "Is this because the drive is
> damaged,
> : or because the disk doesn't have any boot code?"
> :
> : It's possible that the disk was written, or the drive is, out
> of
> : alignment. Although the recalibrate - the "thud thud thud" you
> describe
> : - should get it lined up over track 0. That may not get the
> head to
> : where the data is if the drive that wrote the disk wasn't in
> good shape.
> :
> : Let's try this:
> : Power off the system. Drop a disk into the drive, and power it
> back up
> : up. Wait until the recalibrate rattle finishes, give it another
> couple
> : of seconds, just to be sure, then hit ctrl-reset. If you're not
> dropped
> : into the monitor (showing a "*" as a prompt) then do a
> CALL -151 to get
> : into it. Once there, take a look at memory from about $0803 on
> to $08FF.
> :
> : If most of the gibberish you see as output from that is a
> pattern of "FF
> : FF"s, alternating with 00s, then nothing is getting from the
> disk to the
> : computer, and it might be the fault of the card, the drive, the
> disk, or
> : all three. More testing is in order to see where the fault
> actually is.
> : If there's proper boot code there, then the disk itself is
> suspect - The
> : drive can read the bootstrap code, but can't proceed beyond
> that point
> : for some reason. Perhaps due to blown/non-standard sector
> marks,
> : corruption of the boot track, or who knows what else.
> :
> : I can't take you much further than that for troubleshooting
> right now,
> : but it's a place to start looking.
> 
> Is it possible that the disk is 16 sector and the
> Disk II controllers are 13 sector?

I'd say that's possible (After all, it's also possible that tomorrow 
morning I'll wake up sneezing one-troy-ounce .999 pure gold ingots :) ) 
but I have no idea how a 16 sector disk in a 13 sector drive would 
behave, or if the given symptoms would indicate that was the case. I 
came into the game well after the 13-->16 sector changeover (1) and it 
was never a concern for me, so I never learned much about it other than 
it existed, and had something to do with the controller card (I'm 
*thinking* a chip-swap, but perhaps it was an outright controller-card 
swap?)

I DO recall for sure that on the DOS 3.3 master disk, right alongside 
the classic ANIMAL and BRICKOUT, there was a program - BOOT13, that 
would boot a 13-sector disk. And of course, MUFFIN and DEMUFFIN, also on 
the master, could handle transferring 13 sector data to 16 sector disks, 
and vice-versa. These lead me to think it was a software change, more 
than hardware. Of course, if the software is in a chip, then I guess it 
automatically becomes a software AND hardware change, huh? :) 

(1) ProDOS was about halfway to being dead center on "The Serious Apple 
User"'s radar screen, while DOS 3.3 was starting to lose its popularity 
except amongst the protectors, who based almost all copy-protection 
schemes on DOS 3.3 variants, and the crackers, who had no choice but to 
follow the protectors' lead. Anything "important" was becoming more and 
more ProDOS based, with DOS 3.3 and the various spinoffs it spawned were 
pretty much "games only". 

When I "got serious" about Apples, I jumped into ProDOS with both feet, 
but then went back and learned the crackers' tricks for working with DOS 
3.3 and protected variants, mainly 'cause I wanted to "find out what was 
under the hood". Came in handy once - A friend had loaned me a 
(commercial, so there was exactly one disk, and copy-protected, of 
course) program that got attacked by a 20-some month old kid with a 
handful of french-fries.

Long story short: Because I could boot-trace DOS 3.3 and the variants, I 
was able to disable the copy-protection (A quarter-tracked spiral 
nybble-count written with altered sector marks and nybblizing table, 
using an oddball skew table and oversized sectors on a drive that was 
probably spinning somewhat faster than normal) and salvage the disk.

-- 
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
I respond to Email as quick as humanly possible. If you Email me and get no 
response, see <http://www.sonic.net/~dakidd/main/contact.html> Short
form: I'm trashing EVERYTHING that doesn't contain a password in the subject.