Service manual
DOUBLE-DENSITY
DISK
CONTROLLER
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4
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INTERNAL·DRIVE
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To perform the diagnostics, you will need at least two blank, 5.25-inch, soft-sectored
diskettes.
It
does not matter
whether
these soft-sectored diskettes are single or double
density, nor
whether
they are signal or
double
sided.
Those
who
have single-sided disk drives
and
are uncertain
whether
they have installed
the Controller or disk drives correctly,
should
boot
up
the diskette labeled
"Hard
Sectored" in a hard-sectored disk drive
connected
to
an
H-88-1, single-density, floppy
disk controller, and
then
run
the diagnostics from the hard-sectored diskette.
The
diagnostic and conversion diskette
supplied
with
the disk controller allows you to
"check
out"
or troubleshoot your disk system
and
move software from the hard-sectored
diskettes used by the single-density controller to the soft-sectored diskettes
used
by the
double-density controller, Z-89-37.
The
diagnostic
routine
is
supplied
on a 5.25-inch bootable diskette labeled "Soft Sec-
tored." Customers also receive a diskette labeled
"Hard
Sectored."
The
only difference
between these diskettes is
the
type of
media
and
the
addition
of the hard-sectored to
soft-sectored conversion
routine
on
the hard-sectored diskette. Otherwise, the programs
that the diskettes
contain
are identical. You can
use
either diskette to perform the
diagnostics, but be
sure
to use the diskette labeled "Soft Sectored" only
in
disk drives
that are connected to the Z-89-37 Controller. You can use the hard-sectored diskettein
an
H-17, H-77, or Z-87
with
an
H-88-1 (hard-sectored) floppy disk interface.
Diagnostic
Routine
BLOCK DIAGRAM