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REGTEST
The
REGTEST
diagnostic
can
be
used
to
verify
that
the
various
registers
on
a
DMAF2 disk
controller
board
are
being
accessed
properly.
REGTEST
assumes
that
the
disk
drives
are
connected
to
the
controller
and
power
is
applied
as
described
in
the
checkout
instructions.
To
use
the
REGTEST
diagnostic,
the
code
must
be
entered
into
the
computer
instruction
by
instruction
using
the
memory
examine
and
change
function
of
the
computer's
monitor.
Program
execution
should
then
be
started
at
hex
location
0100
by
either
setting
the
program
counter
to
0100
and
typing
G
or
by
typing
J
0100
depending
on
your
monitor.
REGTEST
will
then
check
each
register
and
will
alternately
select
drive
0
and
then
drive
1.
Correct
drive
selection
is
indicated
if
the
LED
on
the
front
of
drive
0
lights
briefly
and
if
the
LED
on
drive
1
lights
briefly
when
the
one
on
drive
0
goes
out.
Both
LEDs
should
never
be
on
at
the
same
time.
Both
drive
motors
should
be
running.
If
any
register
errors
are
detected
an
X
will
be
displayed.
If
no
errors
are
detected
a
+
will
be
displayed.
The
diagnostic
should
be
allowed
to
run
until
256+'s
have
been
displayed.
REGTEST
may
be
exited
by
depressing
the
RESET
switch
on
the
computer.
A
diskette
need
not
be
installed
in the
drive.
STEPTEST
The
STEPTEST
diagnostic
can
be
used
to
verify
that
the
track
selection
circuitry
of
the
system
drive
and
the
controller
are
working
properly.
If
desired,
a
blank
diskette
may
be
used
in
place
of
the
supplied
system
diskette.
To
use
the
STEPTEST
diagnostic,
it
should
first
be
entered
into
the
computer
instruction
by
instruction
using
the
memory
examine
and
change
function
of
the
computer's
monitor.
A
diskette
(perferably
blank
or
at
least
write
protected)
should
then
be
installed
in
drive
0
and
the
door
closed.
Program
execution
should
then
be
started
at
hex
location
0100
by
setting
the
program
counter
to
0100
and
typing
Gor
by
typing
J
0100
depending
on
the
computer's
monitor.
STEPTEST
will
then
select
drive
#0
and
check
to
see
if
the
index
hole
sensing
and
motor
control
circuitry
is
working
properly.
If
so,
the
disk
drive
heads
will
be
moved
back
and
forth
between
track
00
and
track
76.
STEPTEST
outputs
no
information
to
the
user--if
the
heads
move
back
and
forth
across
the
diskette,
proper
operation
is
assumed.