Radio Shack TRS-80

tion
#1023.
This
perhaps strange
sort of numbering
is not so strange at
all when
you
consider
the
problems
we
had very
early
in the graphics
game with the fool
carriage return
scrolling
our
light right
off the
screen.
The PRINT AT
statement
does not
trigger
a scroll
after it
has
done
its printing,
EXCEPT
IN THE LAST
LINE,
between
print
positions
#96(9
and
#1023.
Further,
P.AT can
directly
address
any of the 1023
printing
locations
(not light
block
locations
—
they
are very
different).
Trailing
semicolons
are needed
only
after state-
ments
printed on
that last or
bottom
line
of the video
"page".
You will soon see
how valuable
all this is.
Oh, It's That
Time
Already?
Let's create
a 24-hour
clock. (Why not
this
obscure
print
statement
logic.)
Type:
sounds like
more
fun than digging
through
all
10
CLS
20
PRINT
AT 407,
**H M
S"
30
FOR H
=
TO 23
40
FOR M
=
TO
59
50
FOR S
=
TO 59
60
PRINT
AT
470,
Hi
":";M;
":";
S
70
FOR N
=
1 TO
500:
NEXT
N
80
NEXT
S
90
NEXT M
100
NEXT
H
and RUN .
Nothing to it.
Ahem!
"Hello? Bureau
of
Standards?"
Of
course the
accuracy of
this
timer depends
on
how
closely
you
calibrate
it.
We
know
that
the
TRS-80 with
LEVEL I
BASIC
will
execute
somewhere
around
500
simple
FOR-NEXT
loops
per second when
written
as
shown
in line
70
—
a
multiple
statement line. If
you
really
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