Before we begin describing any electrical aspects of the mountain, let’s look at the characteristics of the two rivers. River A flows hidden from the left and River B from behind the right side. They combine and flow out the right side together. We cannot see the actual rivers, but just the end result. If either river is flowing the output is visible out the right side of the mountain. If both rivers are flowing, the bank in the middle overflows. The logic Truth table – Wikipedia for these conditions is:
| River A | River B | River A and B | River A or B |
| Not Flowing | Not Flowing | false | false |
| Flowing | Not Flowing | false | true |
| Not Flowing | Flowing | false | true |
| Flowing | Flowing | true (overflow in the middle) | true |
An observer would be able to determine the status of the rivers without seeing the input. Before you scoff at such a trivial computer, complex decision trees have been built using only water gates. Fluidics – Wikipedia
Solar Panel or Piezoelectric Crystal Power Source
To produce digital logic output, we must have a reliable voltage source. Both solar panels and piezoelectric crystals can produce. Two pieces of metal slightly separated can hold the output of a voltage source for a considerable length of time. These Capacitor – Wikipedia devices also smooth out the voltage even when the source is operating. We will discuss capacitors much more deeply when discussing clocked circuits, but all digital circuits require a stable input voltage.
There are many logic gates, but we will only cover a few. Most of the others are combinations of these.
AND GATE
In our river example above, the output Q would only be true if both river A and River B were flowing.
OR GATE
In our river example above, the output Q would be true if either River A or River B was flowing. So the blue output in the middle is an AND circuit and the output on the right is an OR circuit.
EXCLUSIVE OR GATE
This gate is true if either input A or input B is true, but not both. We will use it when we explain adding numbers.
INVERTER GATE
An inverter gate just reversed the input. If A is true then Q is false. If A is false then Q is true.
Additional electrical components are needed for a useful circuit.
Capacitor
A capacitor is a mechanical device that can temporarily store an electrical charge (voltage). The most common type found in nature or manufactured consists of two plates of metal separated by an insulator. The voltage difference between the plates causes electrons to accumulate on one plate and be minimized on the other plate. When the voltage source is removed, the charge will remain for some time. The length of time depends on the load using the stored voltage.
Resistor
A resistor slows down the flow of current causing a difference in voltage between the input and output.
Physical Structure Holding Logic Gates
We will use in our example the output of a silicon volcano. This output is basically liquid glass flowing down the side of the volcano. It consists of silicon with metal impurities. If the mountain bulges like Mount St. Helens did in 1980, it can crack the sheet of silicon (Obsidian – Wikipedia) into thousands of pieces, each capable of becoming a solar cell or silicon logic gate.
This is a type of transistor. It is a silicon base with some positive doping impurities, oxidation on top of that, and a metal coating on top of the oxide layer. Negative doping completes the circuit. Extrinsic semiconductor – Wikipedia. A constant voltage is applied from the left. The data signal is applied to the middle (gate), and the output (drain) will depend upon the voltage applied to the gate. The yellow portion will either constrict or expand depending on the voltage of the gate. That value will apply pressure on the depletion region restricting the voltage present at the drain.
For simplicity, we will say that the voltage at the gate is either 0 or 1 volt. The output will be either 0 or 1 volt corresponding to the input. Two gates one after the other with the output of the first transistor becoming the source of the second transistor is an AND gate. If instead, we connect the output of two transistors together, it becomes an OR gate. This is the implementation of logic in silicon.
Digital Output determined by Input and Logic Gates Used
For example, the following circuit would have a positive output (true) if the first two inputs were true and the third was false. These are dynamic circuits, meaning that as the input changes, the output immediately reflects the new values.
What time is it?
We can now connect our solar cells in the drawing of Mt. Electra to the logic gates we just created.
As the sun rises, the solar cells are illuminated in order. One, then one and two, and finally all three. EET is early earth time. A combination of logic gates allows us to create billions of unique outputs. As we will see later, at some point, it becomes more efficient to minimize the number of logic gates and use software to perform advanced calculations. But before software, it was still possible to produce significant data output using elemental logic gates.
The following is a bit contrived but certainly is possible.
The First TV Transmission
We are going to now build a useful electronic circuit. This could have occurred anytime after volcanoes began coating mountains with Obsidian – Wikipedia or other silicon compounds. A sample mountain has a 35 symmetrical segments arranged in a 5×7 matrix. Each segment acts as a solar cell and also has an output AND gate that allows the reporting of the status of the solar cell. IE – if the solar cell has light input, the output will be on. Here is an image of the letter H projected on the back wall of a cave, which I believe eventually was owned by Plato.
Solar Cell Output
StatusTest Pulse
The output will be + if the solar cell has light at test time
- The status test pulse is applied sequentially to each row of solar cells.
- Each cell would produce an output that reflected whether the cell was receiving light.
- Row 1,2, and 3 output would be 10101
- Row 4 output would be 10001
- Rows 5,6 and 7 would be 10101
- The data output would be 10101101011010110001101011010110101
- This output stream would then be sent down a conductor to Mt. PBS to a MOS-FET transistor that would broadcast the data.
The source would be a million volts created by solar cells, the gate would be the output (digitized letter H), and the drain would be a river of gold acting as an antenna broadcasting the data to the entire universe..
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