56 lines
1.3 KiB
Markdown
56 lines
1.3 KiB
Markdown
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![](./assets/logic-gates.jpeg)
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# NOT Gate
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A binary NOT gate has a single input, and inverts that input.
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## Truth Table
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| $x$ | $y$ |
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| --- | --- |
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| 0 | 1 |
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| 1 | 0 |
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## Mathematical Expression
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A NOT operation is mathematically expressed using a bar:
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$$ y = \bar{x} $$
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# AND Gate
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An AND gate will only output a 1 if *both* inputs are a one.
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## Truth Table
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| $x_1$ | $x_2$ | $y$ |
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| ----- | ----- | --- |
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| 0 | 0 | 0 |
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| 0 | 1 | 0 |
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| 1 | 0 | 0 |
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| 1 | 1 | 1 |
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## Mathematical Expression
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An AND operation is mathematically expressed using a times symbol, or with no symbol at all:
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$$ y = x_1 \cdot x_2 = x_1x_2$$
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# NAND Gate
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A NAND gate outputs a 1 *unless* both inputs are enabled.
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## Truth Table
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| $x_1$ | $x_2$ | $y$ |
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| ----- | ----- | --- |
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| 0 | 0 | 1 |
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| 0 | 1 | 1 |
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| 1 | 0 | 1 |
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| 1 | 1 | 0 |
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## Mathematical Expression
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A NAND operation is mathematically expressed using a bar over an AND operation:
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$$ y = \overline{x_1 \cdot x_2}$$
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# OR Gate
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An OR gate outputs a 1 if either or both inputs are enabled.
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## Truth Table
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| $x_1$ | $x_2$ | $y$ |
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| ----- | ----- | --- |
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| 0 | 0 | 0 |
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| 0 | 1 | 1 |
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| 1 | 0 | 1 |
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| 1 | 1 | 1 |
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## Mathematical Expression
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A mathematical OR is notated with a $+$ symbol.
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$$ y = x_1 + x_2 $$
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