ea971d5a3a48a14046953140e4bbfbbd.ppt
- Количество слайдов: 66
Languages of Computing Alan Blackwell CU Computer Laboratory
Part 1 Languages for storing data
Binary digits (bits) =1 =0
Bits = 0100100
Bytes 01000001 01101100001 01101110 00100000 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 bytes = 400, 000 kilobytes = 400, 000 megabytes
External hard drive (terabytes)
External hard drive (terabytes) 1 terabyte = 1 trillion bytes = 1, 000, 000 kilobytes = 1, 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 (k. B) megabyte (MB) gigabyte (GB) terabyte (TB) ASCII = 1, 000 bytes = 1, 000, 000 bytes
Part 2 Types of data language
Plain text
Numbers 0 = 0000 1 = 00000001 2 = 00000010 3 = 00000010 … 254 = 11111110 255 = 1111
Numbers
Encoding colour 11001000 (= 200 Red) 01100100 (= 100 Green) 11001000 (= 200 Blue) 11001000 011001000
Picture elements (pixels) 900 pixels (30 x 30)
Compression 36, 000 pixels (180 x 200) JPEG level 12 (high quality) File size: 40 k. B 36, 000 pixels (180 x 200) JPEG level 0 (low quality) File size: 14 k. B
Resolution A 10 k. Pixel camera (100 x 100 greyscale)
Encoding sound 0 | 237 | 10 | 56 | 235 | 12 | 3 | 45 | … . WAV[e] file or (compressed) MP 3
Encoding programs 10100000 01000010 11101001000 = MOV AX, 0 x 0082 E 984 H or, “get the data at memory address 4385096” (in the particular language of Intel microprocessors)
Central Processor Unit Once millions of instructions per second (MIPS) Now, billions of clock ticks per second (Giga. Hertz, GHz)
Geek speak checklist plain text ¢ resolution ¢ compression ¢ GIF, JPEG, MP 3, WAV, MPEG ¢ ARM ¢ Giga. Hertz ¢
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 ¢ Homework Research into file sizes l Market research (Currys, Staples) l Specify your own computer l
ea971d5a3a48a14046953140e4bbfbbd.ppt