Computers use binary and logic gates to make calculations.

Binary is in 1s and 0s. 1 represents ON and 0 represents OFF. You can use these basic inputs/outputs and boolean logic to create system for operations.

Binary is used because circuit only check for two states which are 1 or 0.

You will also need to understand and produce simple logic diagrams using the operations NOT, AND and OR.

Gate | Picture | Function |
---|---|---|

NOT | If the input is 1 this gate will output 0.If the input is 0 this gate will output 1. | |

AND | Outputs 1 ONLY if both A and B are 1. Otherwise outputs 0. | |

OR | Outputs 1 if AT LEAST one of the inputs is 1. Otherwise outputs 0. |

You must also know how to draw out their truth table.

Not truth table

A | Q (Output) |
---|---|

1 | 0 |

0 | 1 |

And truth table

A | B | Q (Output) |
---|---|---|

1 | 1 | 1 |

1 | 0 | 0 |

0 | 1 | 0 |

0 | 0 | 0 |

OR truth table

A | B | Q (Output) |
---|---|---|

1 | 1 | 1 |

1 | 0 | 1 |

0 | 1 | 1 |

0 | 0 | 0 |