Propeller Manual

2: Spin Language Reference – Operators
Bitwise OR ‘|’, ‘|=’
The Bitwise OR operator performs a bitwise OR of the bits of the first operand with the bits
of the second operand. Bitwise OR can be used in both variable and integer constant
expressions, but not in floating-point constant expressions. Each bit of the two operands is
subject to the following logic:
Table 2-12: Bitwise OR Truth Table
Bit States Result
0 0 0
0 1 1
1 0 1
1 1 1
Example:
X := %00101100 | %00001111
The above example ORs %00101100 with %00001111 and writes the result, %00101111, to
X.
Bitwise OR has an assignment form, |=, that uses the variable to its left as both the first
operand and the result destination. For example,
X |= $F 'Short form of X := X | $F
Here, the value of X is ORed with $F and the result is stored back in X. The assignment form
of Bitwise OR may also be used within expressions for intermediate results; see Intermediate
Assignments, page 147.
Be careful not to get Bitwise OR ‘
|’confused with Boolean OR ‘OR’. Bitwise OR is for bit
manipulation while Boolean OR is for comparison purposes (see page 168).
Bitwise XOR ‘
^’, ‘^=’
The Bitwise XOR operator performs a bitwise XOR of the bits of the first operand with the
bits of the second operand. Bitwise XOR can be used in both variable and integer constant
expressions, but not in floating-point constant expressions.
Each bit of the two operands is subject to the following logic:
Propeller Manual v1.1 · Page 165