54 lines
1.6 KiB
Plaintext
54 lines
1.6 KiB
Plaintext
# beans computing
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non-electronic {digital systems} based on manipulating beans according to simple logical rules.
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inspired by {the beans computer}, but going at a lower level.
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the {computadora de papel} is also related as a beans-based, "higher level" computer.
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# projects and prototypes
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{norpet} is a proof-of-concept for ideas we have about beans computing in an 8x8 grid or board.
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# truth tables
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we have only two classes of beans: black (1), and non-black (0).
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these tables correspond to the NOT and NOR logical operations.
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they show their possible inputs at their left, and their corresponding outputs to the right.
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=> ./img/foto_beans-computing_truth-tables.png photo of the NOT and NOR truth tables, composed of beans in a greenish surface
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## NOT
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NOT: the output is the opposite of the input. (table at the top left)
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+ <table>
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+ <tr><th>input</th><th>output</th></tr>
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+ <tr><td>0</td><td>1</td></tr>
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+ <tr><td>1</td><td>0</td></tr>
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+ </table>
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& * input: 0, output: 1
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& * input: 1, output: 0
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## NOR
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NOR: the output is black only when none of the inputs are black. in any other case, the output is non-black. (table at the center) {nor}
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+ <table>
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+ <tr><th>inputs</th><th>output</th></tr>
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+ <tr><td>00</td><td>1</td></tr>
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+ <tr><td>01</td><td>0</td></tr>
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+ <tr><td>10</td><td>0</td></tr>
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+ <tr><td>11</td><td>0</td></tr>
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+ </table>
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& * inputs: 00, output: 1
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& * inputs: 01, output: 0
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& * inputs: 10, output: 0
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& * inputs: 11, output: 0
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if you look closely you'll see that NOT can be defined the same way as NOR.
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by combining multiple instances of this logic operation, we could build any possible digital behavior.
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