Introduction - Tandy DCM212 Operation Manual

Introduction
Tandy's
DCM
212 1200-bps
Intelligent
Modem
has
all
the
features
need-
ed
to
enhance your
data
communications
applications
—
including
a data output
rate
four times
faster
than
that
of
a
300
bits/second
modem.
This
direct-connect, Bell 103/212A
type
modem
is
not only designed
with standard automatic
dial,
answer,
and
disconnect
features,
but
also
with a wide
range of
system configuration
enhancements
as
well. Its
CPU
provides operation
in
both Tandy and Hayes®
protocol
modes
—
each
selectable at the
flip
of a
DIP
switch. In
the
Hayes
protocol
mode, your
Modem
is
AT-compatible and
capable of running with
Hayes
software.
After
dialing a
phone
number,
the
DCM
212
will
monitor
the
call
and
report
its
progress to your computer
over the
serial
RS-232C
link.
You
can
even control the
dialing
method
—
pulse or touch-tone
—
and
the
number
of times
the
phone
should
ring before
being answered.
These
functions
and
others are controlled
by
ASCII
(American
Stan-
dard
Code
for
Information
Interchange) encoded
commands
that
you
program from
your computer keyboard
over the
serial
RS-232C
inter-
face.
Roughly
equivalent to
a telephone operator
making
a
call,
the
DCM
212's features include:
•
Waiting
as
the
phone
rings until
the dialed
number
is
answered
•
Hanging up and
redialing
later
if
the
number
is
busy,
or
if
the
call
has not been answered
after
a
specified
period of time
•
Hanging up
the handset
at
the
end of a completed
call
One
of
the
DCM
212's
more
advanced
features
is
the
ability
to
deter-
mine
your computer's communications parameters
(bit rate,
data
bits
per word,
parity,
and
stop
bits
per word),
and
to adjust
its
own
opera-
tion to
meet
system requirements using a simple
command
code
sequence.
Incorporating a high degree
of
intelligence,
the
DCM
212
allows
you
to operate your computer
virtually
unattended
when
linked
to
a
telephone,
making
possible a
wide
range
of telecommunications
applications.
Used
with the proper
applications software
package, the
Modem
is
capable of performing
operations such
as electronic mail
and
shopping,
central-data-base
access,
home
banking and
remote-
peripheral sharing.