Logic gates

You can build and combine the logic gates outlined on the previous chapter inside Minecraft using just redstone wiring.

Theoretically, it’s possible to create even the most complex computer, but also extremely time-consuming and very hard in terms of hardware design. So far, people have built 4-bit computers, calculators capable of performing square roots, trigonometry calculations and graphing, compilers, working mobile telephones and many more impressive creations.

NOT gate

As we saw before, the NOT gate acts as a signal inverter. Below is its “truth table“. A and B are going to be our inputs for studying logic gates, although of course for the other two gates you can have more than 2 inputs. Notice we are using the numerical values instead of the Boolean values, but they signify exactly the same.

A	NOT A
0	1
1	0

The following is the hardware representation of the NOT gate. It’s what you will be using if you ever decide to design and implement a more complicated circuit. It is made up of three elements: the wire, which is the horizontal line, the triangle, which is the symbol for a diode, and a little circle on the right. Note this circle is actually the negation part and can actually be added to other gates as shorthand for not adding the whole NOT gate.

And here is how you make it in Minecraft:

1

2

3

4

5

6

7

8

9

10

The levers are just an example power source, it will work with any of them
The redstone dust on the left acts as the input wire
The orange blocks are orange wool, but you can use any solid block
The redstone torch must be placed on the sides or the top of the block, it cannot be on the block beside it. It must be a redstone torch, as any other power source will not switch off when powered itself.
The redstone dust on the right acts as the output wire

OR gate

OR gates produce an output when any of their inputs are True.

A	B	A OR B
0	0	0
0	1	1
1	0	1
1	1	1

Hardware representation:

The Minecraft version:

1

2

3

Levers act as toggle-able power sources.
This is one of the simplest gates to build in Minecraft – you just have to connect both redstone wires together. If one input wire turns on, so will the output wire.
If both wires turn on, there is no problem – the output will just be on as well.

AND gate

AND gates produce a True output only when all of their inputs are True.

A	B	A AND B
0	0	0
0	1	0
1	0	0
1	1	1

Hardware representation:

The Minecraft version:

1

2

3

4

5

6

7

8

Again, the levers are just an example power source. Each one of them is one input – we will call them A and B. They are connected to the orange wool by redstone dust (barely visible in the image).
The line of solid blocks is only necessary to make sure we have somewhere to place our redstone torches.
Turning on one of the inputs will power off the corresponding redstone torch on the top of the solid blocks.
As you can see if you’re trying this in your own world, the wire on top of the middle block will only turn off once both torches are off, that is, when both inputs are on.
When on, this middle wire is powering the block underneath it – and thus unpowering the torch attached to the side.
The output wire reflects the AND of both levers. It will only turn on if both levers are on, which makes both torches switch off, which unpowers the middle wire, so the output torch has the default behaviour (on).
As an interesting note, by removing the middle torch and taking the output directly from the middle wire we create a NAND gate – in real life, AND gates are also slightly more complex versions of NAND gates and occupy more silicon area, just like in Minecraft.

Previous - Boolean logic

Next - Command blocks

Logic gates

NOT gate

OR gate

AND gate

Address

Map

Contact