C021TVI1S1 ICN 1 Binary coding 1 Data representation as bits 2 Store images or sounds 3 Compression 4 Data organisation 5 Database Why code information Various and heterogenous ID: 762450
Download Presentation The PPT/PDF document "C021TV-I1-S1 ICN : 1. Binary coding 1..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
C021TV-I1-S1
ICN : 1. Binary coding 1. Data representation as bits2. Store images or sounds3. Compression4. Data organisation5. Database
Why code information? Various and heterogenous information, more or less structuredPicked up by human senses or toolsHow to represent it?Digitalisation and digital coding
At electronics level Either the electrical current passes, or it does notBinary coding with 0 or1Bit = Binary DigitToday’s computers are based on electronicsSoon, photonics or quantics?
Bits operations Transistor = miniature switch A tap to manage the electrical current
Bits operations Transistors create logical gatewaysAND, OR, exclusive OR, …Then bit adders, … OR X Y Z X Y Z 0 0 0 0 1 1 1 0 1 1 1 1
Code numbers Bits are limited to 2 valuesAssemble bits to code higher numbersOne byte = 8 bits = 256 values (from 0 to 255)To code an age, only 7 bits are needed (from 0 to 127)To code temperatures, ilmore is neededNegative numbersAnd also decimals The computer can handle the most common kinds of numbers
Doesn’t matter what’s inside The computer can handle numbersBut it doesn’t care what they meanThe programmer or the user has to enter the numbers the right wayWhat measurement unit?Understand the results correctly
Code text Many ways to store a letterOne bit per box to display?What height and width?What if we add colours?ASCII code8bits numeral = 256 possible charactersExtended by Unicode to manage all languages The font’s drawing ( typeface ) is only needed for display
To sum it up The electrical current codes bits 0 or 1Those bits are assembled to represent numbers,or letters, etc.Electronic circuits perform calculations with those numbersWithout knowing their signification
Illustrations p. 2 : 20050501_1315_2558-Bimetall-Zeigerthermometer.jpg CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/) , via Wikimedia Commonp.2 : Little visuals : https://stocksnap.io/author/401