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Concept & Teaching Approach

Draft

Test version of this page - content is basic for now and will be expanded.

Learning by operating the hardware yourself

On every level, the player directly sets the control signals for that tick: which path a multiplexer should select, which operation the ALU should perform, whether a given register's write-enable is on or off. The game does not infer any of this automatically from the instruction - if you set a signal wrong, the computed result is wrong, and you see it immediately.

Hint

Immediate, concrete feedback loop is the core teaching mechanic.

For example, on a single-cycle level executing an addi instruction, the player has to recognize that the second ALU operand should come from the sign-extended immediate (not the register file), and set the corresponding multiplexer path accordingly - the game won't do that inference for you.

Why this specific progression

  1. Isolated components first - understand what a register, an ALU, or a multiplexer does on its own, with no other moving parts to worry about.
  2. Subsets of processor - understand how components are combined into blocks and what functions they can perform.
  3. Single-cycle processor - the same components, now wired together into something that actually executes instructions, but simplified so each instruction fully completes in one tick.
  4. Multi-cycle processor - the same hardware, reused across multiple ticks per instruction - introduces the idea that hardware is a shared, reusable resource, not duplicated per instruction.
  5. Pipelined processor - the payoff and the hardest section: multiple instructions overlap in flight, which is faster, but introduces real hazards that a naive pipeline gets wrong:
  6. Data hazards, solved via forwarding - bypassing a not-yet-committed result directly to where it's needed, instead of waiting for it to reach the register file.
  7. Control hazards, solved via flushing - when a branch is taken, the instructions that were speculatively fetched right behind it turn out to be wrong and have to be discarded.