Building a redstone computer? Learn the logic first
A redstone computer is a working processor built inside Minecraft from redstone dust, torches, repeaters and comparators. The Minecraft Wiki's guide describes the same parts a real computer has, an ALU, a control unit, data and instruction memory and buses, and warns that redstone computers are extremely slow: a redstone tick is 0.1 seconds, and even the fastest take seconds to complete one calculation. Every redstone build is digital logic underneath, so the circuits below carry straight over.
How redstone maps to logic gates
The Minecraft Wiki's logic page lists the standard building blocks. A redstone torch with one input is a NOT gate, the most commonly used inverter. A torch fed by two or more inputs is a NOR gate, which makes NOR the basic gate of redstone. OR can be plain wire joining the inputs, and AND is usually built as a NOR with inverted inputs. Each torch adds a delay, and long lines need repeaters, which is why larger redstone computers run slower. (digiwleea is an independent project, not affiliated with Mojang or Microsoft.)
Why it helps to learn the logic first
Redstone is a great place to build, but a slow place to find out why a circuit works. digiwleea teaches the same circuits in a simulator made for it: you build NOT and NAND from CMOS transistors (in real chips NAND, not NOR, is the cheapest gate), then adders, latches, registers, RAM and a control unit, and finally an 8-bit CPU that you program in assembly, with every part checked against its truth table. Once you know exactly what an adder or a register must do, building it in redstone becomes a translation job. The lab and the first act of the course are free in the browser.
| Redstone | digiwleea | |
|---|---|---|
| Basic gate | NOR (a torch with two or more inputs) | NAND and NOR from CMOS transistors |
| Signal speed | Redstone ticks of 0.1 s; torches and repeaters add delay | Settles at once on every change |
| Checks your circuit | No, you test it by hand | Yes, every part against its truth table |
| Path to a CPU | Community tutorials | 40+ level course + theory lessons |
The parts of a redstone computer, built live
- Gates from NOR only, the way redstone makes them: NOT, OR and AND from NOR gates.
- Adders: the half adder, the full adder from NOR gates and the 4-bit ripple-carry adder.
- The ALU: the 1-bit ALU slice and the 4-bit ALU.
- Memory: the SR latch from NOR gates, the D flip-flop and a 4-bit register.
- Addressing and counting: the 3-to-8 decoder that picks a memory cell and the synchronous counter behind a program counter.
- Output: the BCD to 7-segment decoder for number displays.
- The whole CPU: the CPU simulator and the build a CPU from scratch guide.
No sign-up is needed to start: open the lab and place your first transistor, or read the free theory course. The account (and the AI tutor) are optional.
See for yourself: build a logic gate from transistors in the simulator, then follow the path from sand to an 8-bit CPU.
Open the digiwleea lab →Frequently asked
How do you build a computer in Minecraft?
With redstone logic: torches act as NOT and NOR gates, and from those you build adders, an ALU, memory cells, registers, a program counter and control logic, the same parts a real CPU has. Designing each part as a logic circuit first makes the redstone version much easier.
What logic gates can you make with redstone?
All of them. A redstone torch with one input is a NOT gate and with two or more inputs a NOR gate; OR can be plain wire, AND is a NOR with inverted inputs, and XOR is built from several torches or from newer components.
Why are redstone computers so slow?
Redstone updates in ticks of 0.1 seconds, and torches and repeaters each add delay, so a signal crossing a large build takes many ticks. The Minecraft Wiki notes that even the fastest redstone computers take seconds per calculation.
Is NOR or NAND the basic gate?
In redstone it is NOR, a single torch with several inputs. In CMOS chips NAND is the cheapest gate. Both are universal, so either one can build every other gate, as the NOR-only and NAND-only builds here show.