Commodore Plus 4 - Page 151

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LET I LET | vanab/e expression
The word LET is hardly ever used in programs, since it is not neces
sary, but the statement itself is the heart of all BASIC programs. When
ever a variable is defined or given a value, LET is always implied. The
variable name which is 10 get the result of a calculation is on the left
side of the equal sign, and the number or formula is on the right side.
EXAMPLE;
10 LET A - 5
20 B - 6
30 C = A * B + 3
40D$= "HELLO'1
LOCATE L0CATE ^-coordinate, y-coordinate
The LOCATE command lets you put the pixel cursor (PC) anywhere
on the screen. The PC is the current location of the starting point ol the
next drawing. Unlike the regular cursor, you can't see the PC, but you
can move \\ with the LOCATE command* For example:
LOCATE 160, 100
positions the PC in the center of the high resolution screen. You won't
see anything until you actually draw something. You can find out
where the PC is at any time by using the RDOT(0) function to get the
X-coordmate and RDOT(1) to get the Y-coordinate. The color source
of the dot at the PC can be found by printing RDOT(2). (In all drawing
commands where a color option is available, you may select a value
from 0 to 3, corresponding to the background, foreground, multicolor
1, or multicolor 2 as the color source.)
MONITOR
MONITOR
This command takes you out of BASIC into the built-in machine lan
guage monitor program. The monitor is used to develop, debug, and
execute machine language programs more easily than from BASIC.
See the section on monitor commands for more information. (When
in the monitor, typing an X and hitting >_BETURN i sets you back
to BASIC.)
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