Kablow!

Logic gates and Boolean logic

Apprends en jouant

Réponds à ces questions pour gagner de l'énergie, puis pêche et explore. Sans compte.

Pour les enseignants : diapos de leçon, notes de révision prêts à l'emploi pour Logic gates and Boolean logic (Computer Science, Computer Systems) — utilise-les en cours, ou lance le thème en activité de classe interactive que tes apprenants jouent en direct.

Notes de leçon

Boolean logic

  • Boolean logic works with values True (1) and False (0). Computer circuits are built from logic gates that process binary inputs.

The main gates

  • NOT (inverter): output is the opposite of the input. NOT 0 = 1; NOT 1 = 0.
  • AND: output is 1 only if both inputs are 1.
  • OR: output is 1 if at least one input is 1.
  • (Some courses also use XOR: output 1 if the inputs are different; and NAND, NOR.)

AND requires both inputs

AND requires both inputsABANDQABQ000010100111

Truth tables

  • A truth table lists all input combinations and the output. For two inputs there are 4 rows (00, 01, 10, 11).
  • AND: 0 0 0 1 (for 00, 01, 10, 11). OR: 0 1 1 1. XOR: 0 1 1 0.

All four input combinations

All four input combinationsABORQABQ000011101111

Combining gates

  • Gates can be combined into logic diagrams. Q = (A AND B) OR C. For three inputs there are 8 rows.
  • Write a Boolean expression (A AND B, NOT A) and work out each output step by step.

Q = (A AND B) OR C

Q = (A AND B) OR CABCANDORQABCQ00000011010001111000101111011111

Uses

  • Logic gates are the basis of processors, memory, alarms and decision circuits, e.g. a car alarm sounding if (door open AND ignition off).

Diapos

Sign up free to view the lesson slides

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

Questions d'entraînement

Aperçu gratuit — 8 sur 34 questions. Inscris-toi pour toutes les voir.
  1. 1.What is Boolean logic?

    Easy
    • Alogic using True and False values
    • Blogic using text
    • Clogic using colour
    • Dlogic using hardware
  2. 2.What does a NOT gate do?

    Easy
    • Ainverts the input
    • Badds inputs
    • Cchooses the larger
    • Dstores a bit
  3. 3.What is the output of OR with inputs 0 and 0?

    Easy
    • A0
    • B1
    • C10
    • Dundefined
  4. 4.What is the output of OR with inputs 1 and 0?

    Easy
    • A1
    • B0
    • C10
    • Dundefined
  5. 5.What is the output of AND with inputs 1 and 1?

    Easy
    • A1
    • B0
    • C2
    • D11
  6. 6.What is NOT 1?

    Easy
    • A0
    • B1
    • C2
    • Dundefined
  7. 7.What is the output of XOR with inputs 1 and 1?

    Easy
    • A0
    • B1
    • C2
    • Dundefined
  8. 8.What is the output of XOR with inputs 1 and 0?

    Easy
    • A1
    • B0
    • C2
    • Dundefined

Unlock all 34 questions & more

Crée un compte gratuit pour voir toutes les questions, les diapos, les cartes mémo et les notes de révision de ce thème.

Annales

Les annales d'entraînement pour ce thème arrivent bientôt.
Bientôt disponible