Date   : Sun, 08 Sep 1991 02:14:41 GMT
From   : cis.ohio-state.edu!zaphod.mps.ohio-state.edu!menudo.uh.edu!mtecv2!tamsun!tamuts!jdb8042@ucbvax.Berkeley.EDU (John Donald Baker)
Subject: QX-10 Hard Disk (Comrex Comfiler) questions

Howdy!  'gratulate me!  'gratulate me!
 
I just bought an Epson QX-10 with a Comrex CR-1510 ComFiler hard disk!!
Unfortunately, the ComFiler flaked out very soon after I got it home.  I
was wondering if there is any chance of resurrecting it.
 
The man I bought it from was one of those "befuddled users" who just
managed to stumble through enough of ValDocs to write letters and never
bothered to become proficient with it or the machine.  Consequently, the
hard disk was not connected when I went to examine the machine nor were
any logical drives assigned to HD1 and HD2.  I decided to hook the disk up
and see what it was all about.  After noting the orientation of the
connector on the interface card in the QX-10, the hard disk was turned on.
 
A directory of the disk (which I assigned to C: and D: via SETUP) appeared
with no hint of trouble.  I had brought FBAD v7.0 with me and it declared
that there were no bad blocks on either C: or D:.  Satisfied with the
performance, I paid the man and took my new play-toy home.  I must note
that I was unable to locate references to any disk-parking software either
in the manuals or on any disks I had immediately at hand.  Thus, I simply
turned the system off (CPU first, then the hard disk--as I _later_ learned
is correct).
 
When I set the system up at home, all appeared to be well at first.  I got
a directory listing of the disk and was satisfied that I had done no serious
damage by not parking the heads.  I then worked with files on floppies
exclusively for about three hours (maintenance and exploration).  I then
attemped to access the hard disk.
 
Lo, and behold!  I was greeted with a 'Not Ready' error.  A retry resulted in
a 'R/W' error and after a few 'Continue' selections, I got only a partial
directory listing with a few more 'R/W' errors (with Bad Sector reports).
As I had chosen a poor orientation for the drive which blocked the outflow
air vents, I assumed that thermal drift (expansion of the disk causing head/
track mis-alignment) had occured thus accounting for the errors.
 
I shut the system down (this time parking the heads) and let it cool off over
night.  I relocated the drive the next morning and started it up.  No dice!
The drive behaved as erratically as it had the night before.  As I worked
with it, it got progressively worse right before my eyes until I got nothing
but error messages ('R/W' errors).
 
I decided that there was nothing left but to reformat the drive.  (I had the
original floppies for anything of consequence to me.)  The manual says that
formating the 10MB disk would take aboout 25 minutes.  It sat there for 3
hours!!  It very slowly counted off the cylinders and heads until it logged
"Cyl 305  Head 3" at which point the program declared:  "Drive Format
Failure--Contact your dealer for service"  Subsequent access to the disk
results in 'R/W' errors on every sectory of cylinder 0, head 0.  I ran
the other diagnostic software that was supplied and the disk passes a random
seek test and the controller passes its diagnostic tests.
 
Examination of the system revealed that the interface card in the CPU appears
to just bring the expansion buss out to the back of the machine.  From
there, a 40-pin ribbon cable runs through the hard disk enclosure and plugs
into a Western Digital 1002 Hard Disk Controller.  The actual disk mechanism
is a 5.25" Full-height MFM drive by Computer Memories, Inc., model CM5412.
Configuration is 306 Cylinders, 4 Heads.  I suspect that this is analogous
to a Seagate ST-412.  The configuration is also the same as the IBM PC-AT
Type 1 drive.

Could anyone help me test the drive mechanism or any other part of the
system for "low cost" (knowwhutahmean?).  Are there any drives matching the
above configuration available (new or used)?  If a larger disk will replace
it, is there a way to use the full capacity?  I would also appreciate some
education on hard disk systems as implemented on CP/M machines as I have
never used a hard disk on any CP/M machine.  (And it may be some time before
I do.)
 
Thanks.
 
John D. Baker ->An Apple ZCPR3 nut// and new Epson QX-10 owner.
              ->I can live with floppies, but the HD would really be nice.

John D. Baker  ->An Apple 3.5", 5.25", 8" PCPI Applicard ZCPR3 nut//
Internet:  JDB8042@{tamuts|rigel|sigma|summa|zeus|venus}.tamu.edu
BBSs:  JOHN BAKER on Z-Node #45 [(713) 937-8886], The Vector Board
[(716) 544-1863], The Black Box (FIDO 1:106/601) [(713) 480-2686]
Karnage: "Fire at will!"
Wil (desperately dodging a hail of automatic weapons fire): "AAAAIYEEEE!!"
Karnage: "No, no.  Do not fire at Wil, he is my Second Mate.
          FIRE AT THE SEA-DUCK!!"