Specifications
Level
III BASIC
and
TRSDOS
Disk Operating
System
INP and OUT,
which are
no Iongerneeded
Machjne
language subroutines
are
entered
easily using
Model tr's
improved
"DEBUG"
utility, and
previously
"POKED"
values such
as top offorms
are handled
by their
own
rrnidra -^mnan.ic
Vfhile BASIC
programmers Iamitar
with
Model I will feel
right at home,
machine
lan'
gnrage
programmerc
will fiDd a
totally
new
and different architecture
"under
Model
II's
hood." We
think
you
ll agree
it s
quite
an im_
provement
in aUrespect9.
Ilr addition
tothe
commands
listed, Level
IlI
BASIC and
Model II
TRSDOS have
the follow-
ing additiollal
commands,
not
part
ofthe
Model
I system:
ACAIN-Causes
the last command
exe-
cuted to
repeat.
BUILD-Alows
building
a
file for automatic
command
entiy in
place
ofkeyboard
entry
executed
withthe
"Do"
command-
CREATE-Creates
a named
file and
aIIo-
cates disk
storage space
for
lt. Having
pre_
allocated
space
allows faster
file
handling
in
BASIC.
(Space
can
be dynamically
located-)
DO-Executes
a
file created
with
the
"BUILD"
command-
By using "AUTO
DO," a
BASIC
plogram
may be
executect
on
power-
up,
without opelator
ently
ERASE-Cancels
a
dimensioned
artay
ancl
frees
its memory
space.
ERROR-Returns
an explanatioD
of a
specified
error numbel,
FORMS-Formats
the line
printer top of
forms,
length and
width of
forms, aDd
can
send one
characterto
the
ptinter
for
testing
HEX$-Converts
a
decimal
number
to a
hexadecimal
sting.
NULL-Sends
blanks
at the
end of a
line
/^^mm nr^.ri^hel
BASIC
Commands
for Model
I and Model
II TRS-8Os
ABS
APPEND
ASC
ATN
ATTRIB
AUTO
BACI(UP
OCT$-Converts
a
decimal
number to
an
octal stting,
PAUSE
-
lnterrupts
a "DO
file to require
an
operator
action,
such as
inserting
a diskette
wheD
instructed.
PURGE-Automatic
"(ILL'
mode Lists
all
non-system
files
on adisk
and asks
ifthey
are to be
killed.
RENUM-Renumbers
Program
lines
RESET-
Restores
default system
settings
for
all devices.
SETCOM-
Initializes
communicatrons
clnv-
ers for the
se al
ports,
SPACE$-PriDts
a speciJied
number
of blank
spaces.
SPC-Prints
spaces
on
video display
SWAP-Exchanges
the
values of
two named
variables.
WIDTH-Sets
llne width
for v)deo
dlsplay
A-DDITIONAL
OPERATORS:
MOD,
IMP EOV
XOR
(IDteger
Division).
Model II s
new TRSDOS
responds
to
your
commands
with
positiveIeedback. If
you
say
"KILL
'file-name"l
TRSDOS
wiI
respond
with
"'filename'
KILLED'l
or
"
filename
NOT FOUND'I
so
you'll
always
know
what was or
was Dot accomplishedby
your
command.
And backup
(duplicating)
of
a diskette
requires
knowledge
of a master
password, which
gives
you
additionalpro-
gram
and
data secuitY
These examples
are
taken from
version 1.1of
our
Model II system
software.
OI
coulse'
Radio
Shack
will continue
to enhance
the
Level
IIyTRSDOS
Operating
System
for
Modet Ilwithnew
releases.
Additional
laD-
guages
witl also
be made
available and
will
be
announced
as they
ale released
Our
ability
to expand
Model
II's language
capabilities
is enhancedbecause
the system
is
RAM-based,
and
has no
primary
language
inROM.
TRS-80
Model lI
computerc
contain
a
very
small
amount
ofRead'Or
y-Memory
(ROM)'
which
performs
power-on
diagrnostics'
then
automatically
loads
the Operating
System
ftom disk.
The ROM
is
electrically
replaced
byRAM,Ior
a total of
32 or
64K, depending
on
the Model-II
system
you
have.
Model
tr's f_inch
diskettes
contain 76 acces-
sible tracks
of 25 sectors
each-
a sector
contains 256
bytes. A
"glan" is 5
secioG. The
sysiem
diskette
(which
must always
be
present
in Model
II's built-in
disk
d ve) has
65
t6cks, or about
416,000
bytes ofstorage
available
for
your
data and
plograms.
On
non-system
diskettes,
75
tracks
-
about
486,000 bytes
-
are available
to
the use(
Disk rotation
speed
is appro:omately
360
RPM
and
data is transferred
from
disk at
about
62,500
bytes
per
second,
5
times the
speed
ofTRS-80
Model
I's
Mini:Disk
system
Model U's "LevelIIl
BASIC"
-
an expanded
version ofLevel
II-
and a new
command-
compatible
TRSDOS!
Disk Operating
Sys_
teln
occupy
some 70,000
bytes on
the system
diskette,
An overlay
scheme
allows
it to re_
quire
only about
27K of RAM,
leaving
5K free
in a
32K
Model
II ot 37K
in a 64K
system
Command
compatibility
has been
main-
tained
to the
greatest
possible
extent
for
the
colwenience
ofModel
I owners
who
decide
to move
up to the
additional speed
and
capability
of TRS-80
Model
n. The system
uses numbered
erormessages
which
ap-
pear
on
the video
screeD III
a reversed
field.
For convenience,
you
can type
the number
of
the
message and
leceive
a definition
of that
message
on the
screen.
The
commands
listedto the
right are
com-
mon to both
the TRS-80
Model
I and Model
lI
languages. OperatiDg
System
commands
are
in bolder
type.
A few of
these commands
have
a slightly
different
use inModel
U.
For example,
"sYsTEM"
is
usedto enterDOS
and
(option'
ally)
execute
a DOS
command
with
return
to
BASIC.
Anurnber
of
the commands
also
in-
clude
more options
in the Model
II lan$lage
You
will note
the absence
otPEEK,
POKE,
20
DI'MP
EDIT
END
FMI,D
FOR
FORMAT
GOSI'B
IF-TI{EN-ELSE
INKEY$
cI{R$
cLs
DATA
DEFSNG
LEN
LOAD
laD$
MKD$
ON..GOSIJB
ON..GOTO
PUT
READ
BASIC
CLOSE
cvt
DEFINT
CDBL
cLs
cvs
DEFN(X)
CINT
COPY
DATE
DEFSTR
EOF
INPUT
LET
LOC
CLEAR
cos
DATE$
DELETE
ERL
FREE
INSTR
LIB
LOF
MKI$
OPgN
RXM
RND
STOP
CLEAS
CSNG
DEBUG
DIM
ERR
FRx$
INT
!IST
LOG
MKs$
POS
CLOCK
cvD
DAFDBL
DIR
ERROR
GET
KILL
LIST
LPOS
NEW
PRINT
KILL
LLIST
LEFT$
LOA'
LSET
MERGE
NEXT ONERROR
PRINT@
PROT
RESTORE
RESTIME
RETIIAME
RESET
RSET
RUN
RETURN
SIN
TIME
RIGHT$
soR
SAVE
SYSTEM
VAL
SGN
TAB
\'ERIT"I
sTR$
STRING$
TIMES
TROFF
TRON
USR(N)
operating
system
commands
in bolder
tvpe