Campbell Scientific CR9000X Measurement and Control System - Manual (Page 290)

Section 8. Processing and Math Instructions
ACOS Function Example
The example uses ACOS to calculate
π . By definition, a full circle is 2 π
radians. ACOS(0) is π /2 radians (90 degrees).
Public Pi 'Declare variables.
Pi = 2 * ACOS ( 0 ) 'Calculate Pi.
AND Operator
Used to perform a bit-wise conjunction on two numbers.
Syntax
result = number1
AND number2
The AND operator performs a bit-wise comparison of identically positioned bits in
two numbers and sets the corresponding bit in result according to the following truth
table:
If bit in
AND bit in The result
number1 is number2 is is
0 0 0
0 1 0
1 0 0
1 1 1
Although AND is a bit wise operator, it is often used to test Boolean
(True/False) conditions. The CR9000X decides if something is true or false on
the criteria that 0 is false and any non-zero number is true (Section 4.5).
Because AND is a bit wise operation it is possible to
AND two non-zero
numbers (e.g., 2 and 4) and get 0. The binary representation of –1 has all bits
equal 1. Thus any number AND –1 returns the original number. That is why
the pre defined constant, True = -1.
The predefined constant True = -1
The predefined constant False = 0
If number1 is: AND number2 is: The result is:
-1 Any number number2
-1 NAN (not a number) NAN
0 Any number 0
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 AND Temp(3) < 20 Then
X = True
Else
X = False
EndIf
and
X = Temp(1) > 50 AND Temp(3) < 20
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