On-Line - Tandy DCM212 Operation Manual

Tandy
protocol
mode
operation
Analog
self-test
mode
Type
(o)
,
then type
(T)
to
confirm
that the value of
the
ANALOG
LOOP
parameter
is
now
changed
to
Y
Type
®
to
execute the
test
command. The
Modem
displays
CONNECT
and you
are in the
self-
test
mode. Type any
characters
on
the keyboard.
If
the
DCM
212
is
working
properly, the
TRANSMIT DATA
and
RECEIVED DATA
indicators blink
simultaneously
and
the character
you
typed
will
ap-
pear
on
the
display. If not, there are
problems with the
circuit.
Check
all
cables
an
d
conne
ctions
and
run
the
test
again.
To
abort
self-test
mode,
press
f
CTRL
1
(j)
for the abort
character.
ON-LINE
mode
abort
There
are
four conditions
which
will
abort
an
ON-LINE
status
while
you
are in
communications
over the telephone
lines.
•
Loss of
carrier
• Loss of data terminal ready
(DTR)
•
Reception of a long space
• Transmission of
the abort character
Condition
I
—
loss
of carrier
The
carrier
is
the
sound you
hear
if
you
pick
up
the
receiver
while the
DCM
212
is
in
communications with another
modem.
During low
speed
(300 bps) operation, the
carrier
sounds
like
a
steady,
pure
tone.
You
can hear
a change
in the pitch
of
the tone
if
you
type
on
the keyboard.
In
high speed operation
(1200
bps),
the
carrier
sounds
like
running
water,
or
static.
Regardless of the operation speed, the tone
(or noise)
is
the
carrier
signal.
When
the
carrier signal
is
detected,
the
CD
indicator
on
the
front
panel
lights.
If
the
carrier
is
interrupted longer
than
0.3
seconds,
the
Modem
will
begin the disconnect sequence.
The
message
NO
CAR-
RIER
is
displayed
on
your
screen
and
the
Modem
goes
into
the
ON
HOOK
'(off-line) state.
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