NOT( 0011 1001 ) == 1100 0110
not Pseudoinstruction| NOR Operation on Bits | ||||
|---|---|---|---|---|
| first operand | 0 | 0 | 1 | 1 |
| second operand | 0 | 1 | 0 | 1 |
| | ||||
| OR | 0 | 1 | 1 | 1 |
| not OR | 1 | 0 | 0 | 0 |
The not pseudoinstruction
changes each bit in a register.
Each 1 is changed to a 0 and each 0 is changed to a 1. (This is sometimes called "flipping" each bit or "reflecting" each bit.)
not d,s # Load register d with the # bitwise not of register s. # All 32 bits are changed. # (pseudoinstruction)
This is a pseudoinstruction.
The assembler translates it
into a single
basic assembly instruction,
a nor
instruction.
The nor operation is given in the table.
The nor of two bits is equivalent to
applying not to the
or of the bits.
The nor
instruction uses two registers as operands
and writes the result to a third register.
nor d,s,t # $d <— bitwise # NOR $s with $t. # (basic instruction)
Look at the first two columns of the table where the first operand is zero. The nor of the two operands is the not of the second operand.