Radio Shack TRS-80 Model III - Page 255

APPENDIX
G
/
Model I
to Model
III
Program
Conversion
Hints
From
a
language
standpoint, Model
III BASIC is fully
compatible
with Model
I
Level II BASIC. In
fact, the two BASIC'S
are identical,
except
that Model
111 BASIC
includes one
more function,
TIMES.
However, because
of Model Ill's many
special features
not
available in
Model I,
there are
some internal differences which
may require
that
you modify any
Model
1
Level II BASIC
programs
you may have.
1
.
For
a
given
TRS-80
(
16K, 32K
or 48K RAM),
the amount of
user memory
in Model
III is
258 bytes less
than the amount in
Model I.
2.
To
load
a
Level
II BASIC program,
you
must
select
the
Low
(500 baud) cassette
speed on
your Model III
.
3. When running
a Level
II BASIC program which
requires
all-capitals
keyboard
entries,
be sure to select
all-caps
mode.
(
SHIFT)
(
TJT
)
is the on/off
toggle for
all-caps.
4. Unlike
the Model
I, Model III lets
you interrupt
a cassette, line
printer,
or
RS-232-C operation
by holding down
the
(
BREAK) key . Some of
your Level
II
programs
may
need
modification
to take this
feature into
account.
5. The
video
display character
sets are
slightly different
in Model
I and Model
III.
Model
III produces
standard ASCII
characters for
codes 32 through
127; Model I
does not. In particular,
there is no
up
arrow,
down arrow,
left arrow
or right
arrow in the Model
III character
set. However,
Model III
has an additional
set
of
96
special
characters from which
you
can
probably find whatever
you need.
See
the table
of Model III
Character
Codes
for
details.
Radio Shack
Applications
Programs
For a list of which
Model I programs will
run on
Model III and which
won't,
see the
Radio
Shack Computer
Catalog. Most Model
I-only programs will
be available
in
Model
III versions.
Check at your local
Radio Shack.
245