Digital logic
4-bit CPU from logic gates
Build a simple processor from transistors and gates, to see what is really inside a chip.
What you get
A 4-bit CPU executing instructions step by step, with visible registers, adder and clock.
Parts (simulated)
- Built-in logic lab
- Transistors and gates
- Clock and logic probes
Nothing to buy: every component here is simulated in the browser.
Project steps
- 01Build the basic gates from transistors.
- 02Assemble a flip-flop, then a 4-bit register.
- 03Build a full adder in cascade.
- 04Add the clock and the instruction sequencer.
- 05Run a small program step by step.
What you learn
- From transistor to logic gate
- Storage with flip-flops
- Binary addition
- Instruction cycle
For teachers
Get the teaching pack: 6 ready-to-run sessions
Full progression, objectives, student steps and an assessment grid — printable, free.
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