// ROJIRAKU — Logic Circuit Puzzle
Watch on and off
become computation.
Wire logic gates with your finger, build adders and memory, and finally run a program on a CPU you made yourself. Touch first, read later: it all starts with the click of a lamp lighting up.
$ Screens — SCREENS
$ How to play — HOW TO PLAY
There is more than one right answer. Pass every test to clear a stage, and use fewer gates to earn more stars.
- 01Read the goal.You only get the task, such as "Light the lamp only when both switches are on."
- 02Wire it up.Place gates and drag from pin to pin. Wires that are on fill with glowing red particles.
- 03Check.Every combination of switches is tested. Clear it and you get a short note on the circuit you used.
- 04It becomes a part.Every circuit you clear becomes a single box for later stages. XOR goes into the adder, the adder into the ALU.
$ 5 chapters — CHAPTERS
One straight path from a single gate to a simple CPU. Each chapter's final circuit becomes a part in the next chapter.
Chapter 1 Gates
9 stages
- NOT / AND / OR
- XOR
- Everything from NAND
Chapter 2 Combinational
8 stages
- Binary
- Half and full adders
- Multiplexer and decoder
- 4-bit adder
Chapter 3 Memory
8 stages
- Latches and flip-flops
- Counters
- 4-bit register
Chapter 4 Arithmetic
8 stages
- Two's complement, subtraction
- Shifts, zero detection
- ALU
Chapter 5 CPU
5 stages
- Control unit, program counter
- Run a program on your own CPU
$ Pricing — PRICING
All 5 chapters and 38 stages are free to play. There are no in-app purchases. Each chapter opens when you clear the previous one.
To support the app, a banner ad is shown at the bottom of the home screen and the stage list. No ads appear on the board while you build circuits.
You can choose whether to see ads based on your interests (personalized ads) at any time in the app's Settings.