Radio Shack TRS-80 Model III - Page 51

OPERATION
8
/
Using
the
rs-232-c
Interface
What
is an
Interface?
It' s
a
generalized
means of
communication
between
your TRS-80 and
some external
device,
providing the
necessary
conventions
regarding
data-identification,
transmission
rates,
send-receive
sequences,
error-checking
techniques, etc.
However, an
Interface does not
provide the
programming
necessary to use
any
particular TRS-80/
external
device
system.
For
example,
having the
Interface
installed does not
automatically
enable you to
send
BASIC
programs from one
TRS-80 to
another;
to output
to
a
line
printer via the
Interface;
etc. Such
applications
require
"driver programs"
which must be
custom-designed
for the
equipment you
intend to
use.
The
Radio Shack RS-232-C
Interface is
designed to
meet the
EIA standards.
However, we
cannot
guarantee
that it will
work
with all
so-called "RS-232-C
compatible"
devices. Nor
do we
commit
ourselves to
provide
engineering and
programming support
for such
applications,
or
other special
custom-use
situations.
We
do,
however, guarantee
that
our Interface
will
function
correctly with all
our
own
RS-232-C
equipment.
The term
RS-232-C
refers to
a
specific EIA
(Electronics
Industries Association)
standard
which defines a
widely
accepted
method
for interfacing
data terminal
equipment
with data
communications
equipment. The
RS-232-C
Interface is by
far
the
most
universally used
standard
for
interfacing data
processing
equipment. Most
video
terminals,
modems,
card readers,
line
printers,
mini-microcomputers, etc.
,
utilize
the RS-232-C
standard
for data
interchange
between
devices.
Adding the RS-232-C
to your
Model III TRS-80
opens
up
a
whole new world
of
compatibility. The
Computer
can then be
programmed
to
communicate with a
serial
printer, telephone
modem,
serial
display
terminal
—
almost any
RS 232-C
device.
Note:
The
following
information
applies
only if
your
Model
III
TRS-80
is
equipped
with
the
RS-232-C
Interface.
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