COURIER HIGH SPEED MODEMS
• Follow
the
operating
instructions in
Appendix
E,
Dedi-
cated
Line
and
Leased
Line Operation,
if
your
phone
line is
user-installed
or
if it is leased from the
telephone
company.
Also referred to as private, these lines
are
used
for a direct,
continuous
connection
between
two
modems.
The connection is
made
without
dialing.
•
If
your
modem
is installed
in
a
Hewlett
Packard
system
that
uses
the Ack/Enq
communications
protocol,
be
sure
to follow
the
instructions
at
the
end
of
Appendix
E.
•
If
the
modem
is
attached
to a
computer
instead
of a
terminal,
you
need
communications
software. The
software
uses
the
modem's
AT
command
set to control
many
communications
functions,
including
configuring
the
modem,
dialing,
and
answering
calls,
and
also
enables
the
transfer of files
and
other
operations.
Some
users
prefer
their
communications
software
to take
control of
the
modem,
and
are
more
comfortable
with
a
program
that
makes
the
modem
almost
transparent.
Others
prefer
a
program
that
allows
them
to
use
the
modem's
AT
command
set sometimes,
and
their soft-
ware
at
other
times,
depending
on
the
task
at
hand.
Whichever
you
prefer,
review
at
least
the
Quick
Start
(Chapter
3)
so
that
you
have
a basic
understanding
of
the
modem's
requirements
and
operation.
RS-232 Requirements
You'll
need
an
RS-232 cable to connect
the
modem
to
your
com-
puter
or
terminal.
Use
a
shielded
cable
to
ensure
minimal
inter-
ference
with
radio
and
television reception.
The
modem
takes a DB-25P (25-pin
plug,
or
male) connector
at
one
end
of
the
cable.
Computer
equipment
varies, however.
Check
the
serial
port
at
the
rear
of
your
machine,
which
may
be
labeled SERIAL, COMM PORT,
or
some
other
term
(e.g., RS-232).
If
there
are
no
labels,
review
your
machine
documentation
to find
out
which
is the serial port. (There
may
be
more
than
one.)
Don't
use
a
port
marked
PARALLEL, PRINTER
or
AUX.
The physical serial
port
on
the
computer
or
terminal
will
be
either a socket (female)
or
plug
(male)
that
typically accom-
modates
25
or
9 pins. For example,
the
port
on
the
IBM PC,
PC/XT
and
most
compatibles requires a DB-25S (socket) con-
2-2 Set-up and Testing
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
To Next Page
Loading...
