Radio Shack TRS-80 Modem II - Page 15

3/Using
the
Modem
II
with
Videotex
Software
A
Modem that is
connected to a
Computer
running a
TRS-80
Videotex
software package
constitutes one
of the
most
common (and
exciting!)
ways to use
your Modem
II. This
section
will describe
how to use
the
Modem II
with
VIDTEX
(the
Videotex
program) on TRS-80
Model
I, II,
III, and
Color
Computers.
If
you're
interested
in writing
your
own
programs for
the
Modem II,
refer to the
section of this
manual
entitled
Technical
and
Programming
Information.
It
will
give
you
a detailed
account
of
how the
Modem II
works but on
a
technical
level.
Manual vs*
Automatic
Operation
If
you
want
to
dial an
information service
(such as
CompuServe
or Dow Jones) or
communicate
with
another person
whose computer is
also using
VIDTEX,
you can set the
appropriate MODE
Switch to
MAN
(manual). In this mode,
you
control
what the System does by
"manually"
dialing and
answering the phone.
If you
want the
modem to dial a phone
number
(or
answer the phone) for
you, set the appropriate
MODE
Switch to AUTO
(automatic). In this
mode,
the Modem
dials the phone number you
specify or
answers the
phone when someone
calls you.
Automatic
Mode, for instance,
lets you
dial the
information
service number
without picking
up the
phone —just type the
number (along
with the
proper Modem
II programming
commands)
on the
Computer keyboard. (In
other
words,
let
your
fingers do the
walking
—
but on the
keyboard
instead of the
telephone!)
Originate
vs
Answer
Modes
If
you
want to place a
call (to an
information
service or
another
person using
VIDTEX), set the
other
MODE Switch to
ORIGinate. In
this mode,
the
call "originates"
from your
computer.
If
you
want to
receive
a
call (e.g.,
"answer" the
phone),
set the
appropriate MODE
Switch to
ANSwer.
Note
that
Originate and
Answer Modes
can be
used either
manually or
automatically.
That is,
you
can set
the MODE
Switches to
MAN/ORIG,
MAN/ANS,
AUTO/ORIG, or
AUTO/ANS
depending
on your
particular needs.
During
communication,
you can also
change the
MODE
Switch
settings
without interfering
with
communications.
When you
disconnect from the
information
service,
however,
the
Modem
will
automatically go to
the
"new" mode. For
example, if
the
MODE Switches
are
set
to
MAN/ORIG (the
most common
setting
when
communicating
with an information
service) and
you
want to
switch to
AUTO/ANS on
disconnect,
just change
the settings
before you sign
off.
The
Modem
II will begin
waiting for a
call and
automatically
answer
the
phone
after
it
disconnects
from the
service.
If
you set the
TEST
Switch to REMote
while
communicating
with
an
information
service, the
Modem
will simulate
half-duplex
communication and
the Host
system may send
you
1
'double-characters
.
'
'