Radio Shack TRS-80 MICRO - Control Code Programming Examples

**
Line
Feeds
may be
sent
from
Machine-Language
Programs, but
not
from
BASIC'S
LPRINT
STATEMENT. (In
the
model
I
TRS-80, memory
address
14312
is
a
status/output
port
for
the
printer.
In
the
model
III Z-80
port
251
is
a
status/output
port
for the
printer.
For
further information, see
the
Technical
Documentation
for
the
respective
computer.)
*
2
Normally code
13
(Hex
OD)
causes
Carriage
Return
+ Line
Feed.
However,
after the
code
sequence
of
27,
21 (IB,
15),
input
of
13 causes
Carriage
Return
only
;
27,
22
(IB,
16)
causes
return
to
normal.
*
3
Refer
to
"External
Program
Mode"
on
page
18.
EXAMPLES
OF
CODE
PROGRAM
LINES
LPRINT
CHR$
(8)
;
CHR$
(1)
Backspace
1/120"
LPRINT
CHR$
(13)
Returns carriage
with
line
feed
LPRINT CHR$
(15)
"UNDERLINED"
CHR$ (14)
"NO
UNDERLINE"
Demonstrates
underline
function
LPRINT CHR$
(27);
CHR$
(3)
Moves
3/120"
space
LPRINT CHR$
(27);
CHR$
(14)
All
subsequent
characters
will
be
printed
at
1/12"
spacing.
LPRINT CHR$
(27);
CHR$
(17)
All
subsequent
characters
will
be
printed
at
proportional
spacing.
Special Note:
If
you
use
this
printer
with a
Model
I TRS-80 and
have
BASIC
programs
which
use
top-of-form
(I.E.
programs
for
creating
continuous
form
formats),
you
may
require
a
special
driver
program.
This
is
available
free
of
charge
through
your
local
Radio
Shack store
or
Computer
Center
(special
part
number
700-2007).
(Without
this
special
driver
program
your
BASIC
programs
-
-
set up
con-
tinuous
forms
-
-
may
position
improperly
at
the
top
of
each
new
page
of
a
form.)
17