Commodore VIC-20 - Logical Operators

LOGICAL OPERATORS '
Logical operators perform tests on multiple relations, bit
manipulation, or Boolean operations. The logical operator returns a
bitwise resuit which is either 'true11 (not zero) or "false" (zero). In an
expression, logical operations are performed after arithmetic and
relational operations. The outcome of a logical operation is
determined as shown in the following table. The operators are listed
in order of precedence.
not ,
X NOT X
1 0 ,
0 1 |
AND [
1
1
0
0
Y
1
0
1
0
X AND Y
1
0
0
0
OR
X
1
1
c
c
Y
1
0
1
0
X OR Y
1
1
1
0
!
Just as the relational operators can be used to make decisions
regarding program flow, logical operators can connect two or more
relations and return a true or false value to be used in a decision.
For example:
IF D<200 AND F<4 THEN 80
IF l>10 OR K<0 THEN 50
IF NOT PTHEN 100
68
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