Service manual
4-
6
1i....-
DOUBLE-DENSITY
DISK
CONTROLLER
STARTING THE DIAGNOSTIC PROGRAMS
To start
the
diagnostic programs, boot
up
the
system using
either
the
hard- or soft-
sectored Diagnostic
and
Conversion Utilities diskette.
The
part
number
for
the
hard-
sectored diskette is
HE
890-156.
The
part
number
for
the
soft-sectored diskette is
HE
890-157.
Greater centering accuracy is
required
when
you
are
using
96 TPI drives. Therefore,
it
is
imperative
that
the
diskettes
you
use
with
your
high
capacity
5-1/4/1
floppy
disk
system
have factory-installed mylar
hub
reinforcing rings. All of
the
diskettes
supplied
by
Zenith
Data Systems have
these
rings, as well as Verbatim Datalife diskettes
and
several
other brands.
Do not
use
any
diskettes
that
do
not
have these rings.
The
following procedure
outlines
how
you
should
boot
up
your
Computer.
1.
Turn
on
the
power
to
the
Computer. You will
hear
one
or
two
beeps
and
see
an
H:
in
the
upper
left-hand corner of
the
screen.
2.
Insert
the
Diagnostic
and
Conversion Utilities diskette
into
the
drive.
• Soft-sectored disk goes
into
drive 0 if
you
are using
only
the
Z-3 7 (or compara-
ble
drives
outside
your
Computer)
and
no
drive
in
your
Computer.
• Hard-sectored disk goes
into
drive 2
if
you
are
using
the
Z-89-37 controller
board
with
a Z-89 Computer,
and
drive 2 is connected
to
a hard-sectored floppy
disk
interface (H-88-1). Or,
use
drive 2
if
you
are
using
the
H-88-1 interface
board
with
a Z-90-82 Computer.
• For all others, refer to "Reconfiguration"
on
Page 2-1. Define drive 0
and
insert
the
soft-sectored disk.
3.
Close
the
drive door.