Languages of Computing

Languages of Computing

Alan Blackwell

CU Computer Laboratory

Part 1

Languages for storing data

Binary digits (bits)

= 1

= 0

Bits

= 0100100

Bytes

0100000101101100 01100001 0110111000100000 01000010

Encoding text

01000001 = “A”01101100 = “l”01100001 = “a”01101110 = “n”00100000 = “ ”01000010 = “B”etc …

RAM chip

RAM chip(kilobytes (kb) = 1000’s of bytes)

RAM circuit board (c.a. 1980)

Magnetic drum storage

Magnetic drum storage

Magnetic tape storage

IBM mainframe

Cassette tape

Apple II

BBC Micro

5.25 inch floppy disk (200 kb)

IBM PC

3.5 inch floppy disk

Floppy disk drive

1.4 megabytes = 1.4 million bytes= 1,400,000 bytes= 1,400 kilobytes

Hard disk drive

Hard disk drive (gigabytes)

Hard disk drive (gigabytes)

400 gigabytes = 400 billion bytes= 400,000,000,000 bytes= 400,000,000 kilobytes= 400,000 megabytes

External hard drive (terabytes)

External hard drive (terabytes)

1 terabyte = 1 trillion bytes= 1,000,000,000,000 bytes= 1,000,000,000 kilobytes= 1,000,000 megabytes= 1,000 gigabytes

CD-ROM (megabytes)

DVD-ROM (4 gigabytes)

Flash card

SIM card (kilobytes)

USB flash drive (8 gigabytes)

Geek speak checklist

bit, byte, RAM kilobyte (kB) = 1,000 bytes megabyte (MB) = 1,000,000 bytes gigabyte (GB) = 1,000,000,000 bytes terabyte (TB) = 1,000,000,000,000

bytes ASCII

Part 2

Types of data language

Plain text

Numbers

0 = 00000000

1 = 00000001

2 = 00000010

3 = 00000010

…

254 = 11111110

255 = 11111111

Numbers

Encoding colour

11001000(= 200 Red)

01100100(= 100 Green)

11001000(= 200 Blue)

110010000110010011001000

Picture elements (pixels)

900 pixels(30 x 30)

Compression

36,000 pixels (180 x 200)JPEG level 12 (high quality)

File size: 40 kB

36,000 pixels (180 x 200)JPEG level 0 (low quality)

File size: 14 kB

Resolution

A 10 kPixel camera(100 x 100 greyscale)

Encoding sound

0 | 0 | 237 | 10 | 56 | 235 | 12 | 3 | 45 | …

.WAV[e] file or (compressed) MP3

Encoding programs

10100000 00000000 01000010 11101001 01001000

= MOV AX,0x0082E984H

or, “get the data at memory address 4385096”

(in the particular language of Intel microprocessors)

Central Processor Unit

Once millionsof instructionsper second(MIPS)

Now, billionsof clock ticks per second(GigaHertz, GHz)

Geek speak checklist

plain text resolution compression GIF, JPEG, MP3, WAV, MPEG ARM GigaHertz

Part 3

Collecting and presenting data

Input: Keyboard

Input: Sound card

Input: Flatbed scanner

1000 dpi (dots per inch)

Input: Digital camera

4000 x 3000 = 12 Megapixels

Input: Digital video camera

640 x 480 pixels (VGA)

Input: Webcam

352 x 288 pixels (VGA)

Output: Monitor

1024 x 768 pixels (XGA)

Output: Printer

800 dpi (dots per inch)

Output: Powered speakers

Output: Data projector (“beamer”)

800 x 600 pixels (SVGA)

Geek speak checklist

VGA, SVGA, XGA DPI

Part 4

Internal communication

Motherboard

Expansion RAM (SIMM)

Part 5

External communication

VGA connector

HDMI connector

DVI connector

VGA/DVI Adapter (“Dongle”)

RJ-11 connectors

Don’t confuse Ethernet and Phone!

USB connector

No confusion possible – all peripherals are interchangeable!

Practical exercises

HomeworkResearch into file sizesMarket research (Currys, Staples)Specify your own computer