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Foundations of Technology

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Introduction to Computer Science Principles byDesign

Unit 1: Computer Science Principles byDesign

Learning Cycle 3: Logic: If/Else, Loops, AND, OR, NOT (Microbit)

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Big Idea

In this presentation we will learn how to use If/Else, Loops, AND, OR, NOT in programing the microbit to solve engineering problems.

Foundations of Technology

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What is a Logic?

  • In programming a logic refers to statements or expressions that utilize a boolean value. A true or false value is called a boolean or bool.

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Foundations of Technology

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Logic blocks

There are three groups of blocks under the logic:

Conditionals: If/else

The statements inside the if block

will be executed only when the value

inside the hexagon is “TRUE”

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Example: Conditional

if the boolean statement is

true, the LED will appear

in the left,

Otherwise, it stays

in the center

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Logic Blocks

Comparisons:

Use comparator operators

to evaluate whether the

comparison is true or false.

=, >,<, ≥, ≤,≠

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Example: Comparison

The boolean statement

is false so the else is

executed

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Logic Blocks

Boolean:

Using the logical operators AND, OR,

NOT to evaluate expressions (whether

TRUE or FALSE

(Boolean is the technical term for a

data type that can only be true

or false

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Example: Boolean

True and True will return

a true

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Truth tables for AND, OR, NOT

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AND

TRUE

FALSE

TRUE

TRUE

FALSE

FALSE

FALSE

FALSE

OR

TRUE

FALSE

TRUE

TRUE

TRUE

FALSE

TRUE

FALSE

NOT TRUE

FALSE

NOT FALSE

TRUE

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Example: Boolean

True and False will return

a False

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Example: Try this Program

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Initialize the variables

score and Goal

When button A is

pressed, score increases

by 1.

When score equals Goal,

servo moves to 135 and

microbit displays smiley face,

otherwise, servo stays at 90.

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Example: Try this Program

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Initialize the variables

score and Goal

When button A is

pressed, score increases

by 1

When score equals Goal,

servo moves to 135 and

microbit displays smiley face,

otherwise, servo stays at 90

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Loops

Repetition (iteration) of a command/statement or a group of commands/statements

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Loops

Repetition can be

controlled by a boolean

or a number/index

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Loops

Repetition can be

controlled by a boolean

or a number

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Try this:

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  • For movement, use servo (inside the PINS or SERVO)
  • For sound use the ringtone or play tone (inside MUSIC)
  • For LED display use displays in BASIC
  • Scenario: when the room is full, close the gate, sound an alarm, flash a warning
  • Estimate/count people coming in by any trigger (shake, button press, temperature, light).

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Example of Possible Solution

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