Campbell CR9000, Инструкция по эксплуатации

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Section 8. Processing and Math Instructions
8-15
NOT (-1) = 0
NOT (0) = -1
NOT (NAN) = NAN
(NAN= Not A Number)
OR Operator
Used to perform a bit-wise disjunction on two numbers.
Syntax
result = number1
Or
number2
The
Or operator performs a bit-wise comparison of identically positioned bits in
two numeric expressions and sets the corresponding bit in result according to the
following truth table:
If bit in And bit in The result
expr1 is expr2 is is
0 0 0
0 1 1
1 0 1
1 1 1
Although OR is a bit wise operator, it is often used to test Boolean
(True/False) conditions. The CR200 decides if something is true or false on the
criteria that 0 is false and any non-zero number is true (Section 4.5). In the
CR200, the pre-defined constant, True = -1.The binary representation of –1 has
all bits equal 1. Thus any number OR -1 returns -1. Any number AND -1
returns the original number.
The predefined constant True = -1
The predefined constant False = 0
If number 1 is: Number 2 is: The result is:
-1 Any Number -1
-1 NAN (not a number) NAN
0 Any Number Number 2
0 NAN NAN
Expressions are evaluated to a number (Section 4.5) and can be used in place
of one or both of the numbers. Comparison expressions evaluate as True (-1)
or False (0) For example:
If Temp(1) > 50 OR Temp(3) < 20 Then
X = True
Else
X = False
EndIf
and
X = Temp(1) > 50 OR Temp(3) < 20