NOR logic
From Wikipedia, the free encyclopedia
- This article is about NOR Logic in the sense of building other logic gates using just NOR gates. For information on NOR Gates, see NOR gate. For NOR in the purely logical sense, see Logical NOR. For logic gates generally, see Logic Gate.
Like NAND gates, NOR gates can be combined to form any other kind of logic gate.
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[edit] NOT
This is made by joining the legs of a NOR gate. This is because A and B are always equal, and the NOR will act as an inverter.
| Desired Gate | NOR Construction |
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[edit] OR
An OR gate is an inverted NOR gate.
| Desired Gate | NOR Construction |
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[edit] AND
Made by connecting two NOT gates to a NOR gate.
| Desired Gate | NOR Construction |
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[edit] NAND
A NAND gate combines an AND gate and a NOT gate.
| Desired Gate | NOR Construction |
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[edit] XOR
An XOR gate is a combined AND gate and NOR gate, of which both outputs are connected to a NOR gate
| Desired Gate | NOR Construction |
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[edit] XNOR
An XNOR gate is simply an XOR gate with an inverted output:
| Desired Gate | NOR Construction |
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Alternately, an XNOR gate can be constructed using only four NOR gates as follows. Call the two inputs A and B. The first NOR gate is connected to A and B. The second NOR gate is connected to A and the output of the first NOR gate. The third NOR gate is connected to B and the output of the first NOR gate. The fourth NOR gate is connected to the outputs of the second and third NOR gates.
