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' This example uses logical operators to compare each bit of the first
' operand with the corresponding bit in the second operand to compute the bit
' in the result. In these bit-wise comparisons, a 0 bit is equivalent to a
' false value (F), while a 1 bit is equivalent to a true value (T).
 
' It is possible to use logical operators to test bytes for a particular bit
' pattern. For example, the AND operator can be used to mask all but one of
' the bits of a status byte, while the OR operator can be used to merge two
' bytes to create a particular binary value.
 
' To try this example:
' 1. Choose New Project from the File menu
' 2. Copy the code example below to the code window
' 3. Press F5 to run the example
 
 CLS                                   ' Clear the screen
 PRINT 63 AND 16
 PRINT -1 AND 8
 PRINT 10 OR 9
 PRINT 10 XOR 10,                      ' Always 0
 PRINT NOT 10, NOT 11, NOT 0           ' NOT X = -(X + 1)
 
' The first PRINT statement uses AND to combine 63 (111111 binary) and 16
' (10000). When Visual Basic calculates the result of an AND, it combines the
' numbers bit by bit, producing a 1 only when both bits are 1. Because the
' only bit that is a 1 in both numbers is the fifth bit, only the fifth bit
' in the result is a 1. The result is 16, or 10000 in binary.
 
' In the second PRINT statement, the numbers -1 (binary 1111111111111111) and
' 8 (binary 1000) are combined using another AND operation. The only bit that
' is a 1 in both numbers is the fourth bit, so the result is 8 decimal or
' 1000 binary.
 
' The third PRINT statement uses an OR to combine 10 (binary 1010) and 9
' (binary 1001). An OR produces a 1 bit whenever either bit is a 1, so the
' result of the OR in the third PRINT is 11 (binary 1011). The XOR in the
' fourth PRINT statement combines the number 10 (1010 binary) with itself.
' The result is a 0 because an XOR produces a 1 only when either, but not
' both, bits are 1.
 
' Performing a NOT on a number changes all 1s to 0s and all 0s to 1s. Because
' of the way two's complement numbers work, taking the NOT of a value is the
' same as adding one to the number and then negating the number. In the final
' PRINT statement, the expression NOT 10 yields a result of -11.
 
 STATIC SUB TruthTable (X, Y)
  PRINT X; "     "; Y; "     "; NOT X; "     "; X AND Y; "     "; X OR Y;
  PRINT "     "; X XOR Y; "     "; X EQV Y; "     "; X IMP Y
  PRINT
 END SUB