AQA A-level Computer Science (7517)Specification point 4.6.4.1

AQA 7517 4.6.4.1: Logic gates

The free BugBot lessons that teach this point, a robot to try it on, and the past-paper questions that test it.

Lessons that teach it

  1. A8.1 Logic gates and notation Boolean algebra and logic circuits
    NOT, AND, OR, XOR, NAND and NOR, the notation each board uses, and why NAND alone can build anything.
  2. A8.2 Circuits, expressions and truth tables Boolean algebra and logic circuits
    Reading and drawing circuits, defining a problem in Boolean logic, and sum of products from a truth table.
  3. A8.7 Half adders and full adders Boolean algebra and logic circuits
    The full adder's expressions, building it from half adders, and chaining full adders into a ripple carry adder.
  4. A8.8 D-type flip-flops and clocks Boolean algebra and logic circuits
    Clock signals, edge triggering, the D-type flip-flop as one bit of memory, registers and a divide-by-two counter.
  5. A8.9 Project: the robot's safety logic Boolean algebra and logic circuits
    From a rule table to a Karnaugh map, a simplified expression, a proof and a robot that stops for the right reasons.

Try it on a robot

The task from A8.1 Logic gates and notation, running here. Change the program and press Run.

The specification is AQA's own document; this page says which of our lessons teach point 4.6.4.1 and is not endorsed by the board.