Radio Shack TRS-80 Quick Reference Manual

Color
Computer
MICRO-
COMPUTER
M
Start-Up
1
.
Turn
the television sel
ON.
2.
Select channel 3 or
4.
3.
Set
the
Antenna
Switch
to
COMPUTER
4. Turn on any accessory equipment
(e.g.,
a
printer).
5.
If
you're using a
Program Pak
"
.
insert
it
now, betore
turning
on
the Computer.
6.
Turn
the
Computer ON.
7.
If
you're not
using a Program
Pak'". the Color
BASIC
or
Extended Color
BASIC
start-up
message
will
appear on the TV.
followed
by:
OK
The Computer
is
now
ready
to use.
Note:
Information pertaining to
Extended
Color
BASIC
only
is
shaded
like this
paragraph. Non-shaded
information perlains
to
both Extended
and
non-Extended
Color
BASIC.
Radio
/hack
The
biggest
name
in little
computers
Copyright 1981 by Radio Shack. A
Division of Tandy Corporalio
1
Video
Control
Codes
Dec Hex
PRINT
CHR$
(code)
8 08 Backspaces and erases
current character.
13
0D
Line feed with carriage
return.
32
20 Space
Operators
Each
operator or
group
of
operators
is
precedent over
the
group below
it.
Exponentiation
-,+
Unary
negative, positive
*,/
Multiplication, division
+ .-
Addition
and
concatenation, subtraction
<,>,
=
,<
=
,>
=
,<>
Relational
tests
NOT
AND
OR
Graphic Character
Codes
Given
the color
(1-8)
and the pattern
(0-15). this
formula
will
generate the correct code:
code = 128 +
16
•
{color
-1)
*
pattern
I
'1
1 I
'I
I I I
IS]
I
12
I
13
I
I 14
I
I
15
I
For example
to print
pattern
9 in blue
(code
3), type:
C=
126+16*
(3-1)
+9
" CHRJ
(C)
m]
Functions
Argument
ranges are indicated by
special
symbols:
numeric:
(-10
3B
.
W
38
)
x:
(0-255)
y:
(0-191)
location: (0-65535)
code: (0-255)
str:
string
argument
var.
variable
name
ABS
(numeric)
Y=ABS(5)
Computes
absolute
value.
Returns ASCII code
of
first
character
of
specified
ASC
(str)
string.
A ..'
i. I.
ATN
(numeric)
Y=ATN(X/3)
CHR$
(code)
code
?
CHR$
(
191
)
II
l
'-"I i
I
COS
(numeric)
Y =
C0S<7)
EOF
(I)
ReturnsFALSE(0)ifthereismoredata:TRUE(-1)if
end
of
file
has been read For cassette,/
1. for
keyboard,
/ 0.
E0F=<-1
)
EOF(fl)
EXP
(numeric)
/—numbtir\
Returns
arctangent
in radians.
Returns character
for
ASCII, control, or graphics
Returns cosine
of
an
angle given
in
radians.
Returns
natural
exponential
of
number
Returns truncated (whole number)
value.
FIX (numeric)
Y * F
I
X
(
7
,
6
I
HEXS
(numeric)
Computes
hexadecimal value.
PRINTHEXt
(30)
Y
=
HEX! (X/16)
INKEYS
Checks
the
keyboard and
returns the
key
being
pressed
(if
any).
A$=INKEY*
INT
(numeric)
X=INT(5.2)
Converts a
number
to
an
integer