% Author: Ian! D. Allen - idallen@idallen.ca - www.idallen.com % Date: Fall 2011 - September to December 2011 - Updated 2011-10-19 06:32 EDT % Title: Week 06 Notes for CST8281 - Fall 2011 - [Course Home Page] - [Course Outline] - [All Weeks] - [Plain Text] Midterm Test #1 - 15% ====================== - In class on Friday, October 14. Short answer and multiple choice. - For full mark credit, read the [Test Instructions] for important directions on how to enter your answers on the mark-sense forms. - Calculators are not permitted during the first midterm test. You will benefit from knowing the powers of two from 2\^(-4) to 2\^16 and the decimal and binary values of the hexadecimal digits from zero to fifteen. Of course you can work them out; however, having at least some of them memorized will make things go faster for you on the test. (Remember that hexadecimal “A” = decimal 10 = binary 1010.) Lecture Notes for This Week =========================== From the Class Notes link on the Course Home Page ------------------------------------------------- - [Course Home Page] - [All Weeks] - [120_CharacterEncoding.html] - Character Encoding / Line Ends - know these Seven Famous ASCII Characters: 0D 0A 20 30 41 61 7F - do not memorize any EBCDIC - [130_big_picture.txt] - The Big Picture on Bit Patterns - [140_attack.txt] - Remote Attack Script uses hexadecimal obfuscation - [145_textbook_secrets.txt] - Alcatel-Lucent Traning Manual containing secret messages in hexadecimal - [200_DEBUGbasics.html] - [200_DEBUGhelp.txt] ### Assignments - [Assignment #05] - In-lab assignment on character decoding. No upload needed. - [000_self_mark.txt] - Self-mark of Assignment NN (participation mark) From Blackboard Course Documents -------------------------------- These documents have restricted distribution and cannot be put on the [Course Home Page]. - [02.ppt] - Data Representation - Character encoding: ASCII, Unicode, Line Endings - [06.ppt][02.ppt] - Memory - only read memory speeds on slide 7 this week - omit the rest of this slide set for this week From the Internet ----------------- - - - - - - a joint ISO and IEC series of standards for 8-bit character encodings - - The ISO 8859 Alphabet Soup - From the Classroom Whiteboard/Chalkboard ---------------------------------------- - Your in-class notes go here. ### Character Encoding - Character codes: ASCII, extended ASCII, EBCDIC, Unicode, UTF-8 - ASCII Control Characters (unprintable) - line ends for text files on Unix/Mac/Windows - reading character tables - compare ASCII & EBCDIC for sort order and common printable characters - ASCII puts ‘A’ before ‘a’; EBCDIC does the reverse - tabs vs. spaces - know the Seven Famous ASCII Characters - 0D 0A 20 30 41 61 7F - do not memorize any EBCDIC - how to print the decimal value of 00001111(2) on the screen in ASCII? - decimal value is 15: send 31h and 35h (“1” and “5”) - Problems with all the 8-bit extended-ASCII character sets - can’t have Latin1 French and Latin2 Polish in the same text file: why? - UTF-8 advantages and disadvantages - same as ASCII, no endian-ness, multi-byte, full Unicode, may require more bytes than Unicode - Fonts vs. Character codes - codes only say what letter, not what it looks like - Why can’t French (Latin1) and Polish (Latin2) exist in the same text file? - same problem for all the 8-bit extended-ASCII character sets - Memory speeds (latencies) ([06.ppt][02.ppt] #7) - 1ns-2ns - registers - 3ns-10ns - Level 1 Cache - 25ns-50ns - Level 2 Cache - 30ns-90ns - main memory - 5ms-20ms - fixed hard disk - Source: [06.ppt][02.ppt] slide 7 (under \[Blackboard\] Course Content - Slides) -- | Ian! D. Allen - idallen@idallen.ca - Ottawa, Ontario, Canada | Home Page: http://idallen.com/ Contact Improv: http://contactimprov.ca/ | College professor (Free/Libre GNU+Linux) at: http://teaching.idallen.com/ | Defend digital freedom: http://eff.org/ and have fun: http://fools.ca/ [Plain Text] - plain text version of this page in [Pandoc Markdown] format [Course Home Page]: .. [Course Outline]: course_outline.pdf [All Weeks]: indexcgi.cgi [Plain Text]: week06notes.txt [Test Instructions]: 000_test_instructions.html [120_CharacterEncoding.html]: 120_CharacterEncoding.html [130_big_picture.txt]: 130_big_picture.txt [140_attack.txt]: 140_attack.txt [145_textbook_secrets.txt]: 145_textbook_secrets.txt [200_DEBUGbasics.html]: 200_DEBUGbasics.html [200_DEBUGhelp.txt]: 200_DEBUGhelp.txt [Assignment #05]: assignment05.txt [000_self_mark.txt]: 000_self_mark.txt [02.ppt]: http://blackboard.algonquincollege.com/ [Pandoc Markdown]: http://johnmacfarlane.net/pandoc/