Agenda 7

Courses Wayne State University College of Lifelong Learning Interdisciplinary Studies Program Computers and Society courses, Winter 2001 ( http://www.cll.wayne.edu/isp/drbowen/casw01) Mondays, 6 - 9:40 PM in 113 Rackham Computers and Society GST 2710, Section 988, Call Number 95241, 4 credits Computers and Society AGS 3360, Section 983, Call Number 98319, 4 credits Office hours: Mondays 4 - 6 PM in 113 Rackham	Instructor
	David R. Bowen 2311 A/AB Wayne State University Detroit, MI 48202	Daytime tel: (313) 577-1498 Evening tel: (248) 549-8518 FAX: (313) 577-8585 Home Page: http://www.cll.wayne.edu/isp/drbowen Email: d.r.bowen@wayne.edu

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Last updated: 2/26/01
Link back to course Welcome...

Seventh class: Agenda
Monday February 26

Handouts
1. Agenda
2. Worksheet: Doing Binary Arithmetic With Switches
Passbacks
1. Assignments and Labs (as ready).
Reminders:
1. Before you leave tonight, fill in the online Attendance (Signin) form on the course web site.
2. If you miss a class, before the next class you should go to the course web site (the URL is in the upper left-hand corner of every handout) and review the Agenda for that class, then contact me if you have questions. Assignments and quiz topics are listed on the Agenda.
3. If you need to make up a Quiz, or ask questions, or whatever, my office hours are time set aside for this. These times are Mondays and Wednesdays, 4 - 6 PM, in 113 Rackham (the classroom).
  
  If these times do not work for you, contact me to make other arrangements.
  
  I will not let you start a Quiz if the full half hour is not available before the start of the Monday night (I teach that one, of course) or Wednesday night (someone else teaches that one) class - both start a 6 PM, so 5:30 PM is as late as you can start a Quiz.
Announcements:
1. The Midterm will be the week after Spring Recess, on Monday, March 19. On the class before that, the week before Spring Recess (next week's class) there will be a one-hour Question and answer session for the topics covered on the midterm. One hour may seem like a lot of time, but it is not time to review all of the topics. You will have to choose which ones to ask about. Study the list of topics on this agenda.
2. On the Midterm, you will not be able to complete the Word and Excel work in time if all you have done is the in-class exercises. The Labs are part of the course, and the Quizzes and Exams will assume that you have done the Labs. There is in-class time provided to do the Labs; if you leave early and are not spending that time on the Labs, you need to correct that.
3. Tonight we will start a topic that is very different from anything we have done so far - "Doing Arithmetic With Switches." If you have trouble with this topic, there is an animated example on the course web site, under the section "Online tools / animations."
Spreadsheets - Review
1. Starting Excel with (two ways) or without (one way) opening a file.
2. A spreadsheet is for ______________
3. The Excel document is called a _______________
4. The Excel document is a grid of __________ arranged in ________ and __________
5. What can be in a cell?
  1. Number - how to enter?
  2. Text (why?) - how to enter?
  3. Formula - how to enter?
6. How do you format in Excel? What kind of formatting can you do?
7. How do you edit a cell in Excel?
8. Charting
User interfaces - the way the user controls what the computer does.
1. The two major types (so far) are Command Line and GUI (Graphical User Interface).
2. Levels of the GUI:
  1. Active elements (reviewed last week - buttons, radio buttons, check boxes, etc.)
  2. Dialog - a collection of active elements to accomplish a specific task such as saving a file (drive, folder, name, type). A dialog can have several "Tabs" or pages. In Windows, some common dialogs are:
    1. Save As...
    2. File / Open
  3. Wizard - a series of dialogs to accomplish a specific task

Information

How much information can be stored in n bits?
1. Lowest number that can be stored is zero
2. Highest number that can be stored is 2ⁿ - 1
3. Number of different values (codes) is 2ⁿ
4. 2¹⁰ ~ 10³ = 1,000
A byte - 8 bits. Computers usually handle data in bytes. How much information is this, or how many different codes?

The table below summarizes the forms of computer information; we have not covered them all in class yet.

Types of computer information	Subtypes	Examples
Programs	Operating system	Windows95, Windows 98, Windows NT
		Mac OS 8
		Linux
		Unix
	Application	Word program
		Excel program
		Access program
		Netscape program
Data	System information	User Name and Password
		Internet address
		Network connection
		Printer description
		Icons, screen colors
		Sound files - "The Windows Sound"
	User information	Word processing document - mostly text
		Spreadsheet document - text and numbers
		Database document - text and numbers
		Graphic file - can be animated
		Sound file
		Video - Graphics and sound together
		Macro script - a small program written by a user, stored as a document, executed by the corresponding application

File sizes for numbers
1. ASCII codes will not work for calculations. The ASCII code for 1 is 49 and the ASCII code for 2 is 50. If we add the ASCII codes we get 49 + 50 = 99. This is not the ASCII code for 3, which is 51, but the ASCII code for c, which is not even a number. We must use the binary code for storing numbers to be used in arithmetic. (To display number on the screen or printer, they are generally translated into ASCII by the computer, prior to display. Similarly, numbers come from the keyboard in ASCII and are converted to numbers before storage, if they are to be used for calculations. If you are typing a word processing document, the numbers get stored as characters - ASCII codes.)
2. Computers can store numbers either as integers - whole numbers - or a "floating point" numbers - numbers with a decimal point.
  1. Integers use the straight binary number system as we have learned it in class. There are several storage arrangements. One or more bytes will be set aside for each integer, depending on how large a value we want to be able to store. For signed numbers (ones that can be + or -), generally the high-order bit is used for the sign, which reduces the size of the largest number that can be stored. The standard options are one, two or four bytes per integer. Two bytes is often called a "word", and four a "double word." It is important to pick the right scheme, depending on what range of numbers the program must accommodate. If too many bytes are allotted, storage is wasted, although with the low price of memory these days, that is not as important as it used to be. The real problem comes if too few bytes are allotted; then there are numbers that occur in the real world but cannot be stored in the computer.
    1. Example: What is the largest unsigned integer that can be stored in one byte?
    2. Example: What is the largest signed integer that can be stored in one byte?
    3. Example: What is the largest signed integer that can be stored in two bytes?
  2. Floating point numbers are stored in the form of a decimal number times an exponent, or power, or x × 10y, for example 0.5348 × 10⁺⁴⁷. Standard schemes are four bytes per number, or eight bytes. The exponent in some schemes can be as high as 10⁺³⁰⁰ (a 1 followed by 300 zeroes) or as small as 10^-300
  3. The file size, then, is the number of numbers times the bytes per number. If we have some numbers that are small and some that are large, we can have a mixed scheme. In this case, we find the size for each storage scheme and then add up the individual schemes to find the total.
  4. Example: How many bytes are required for 5,000 integers at two bytes per integer, and 2,000 floating point numbers at eight bytes per number?
Computer programs or instructions. Almost all computers (and all current ones) use the same scheme for storing computer instructions (these would be in exe or com files). Data in the computer is stored in RAM memory, which is organized into bytes. The storage locations are numbered from 0 to the number of bytes of storage, minus 1. That number is called the address. The storage locations must be cheap, because there are so many of them, and hence incapable of doing arithmetic; a special location called the Accumulator is used as temporary storage where arithmetic can be done also. To add two numbers, for example, the computer copies or loads the first number into the accumulator, then adds the second number to the value already in the accumulator, and finally copies the value in the Accumulator (now containing the sum of the two numbers) into the address set aside for the sum. It is important to realize when thinking about this, that the adding, copying or loading does not change what is in the original location, only what is in the final location.

A computer instruction, then, has two parts; a number called the "operation code" or "op code", representing the instruction (simple load from memory to accumulator, add from memory to accumulator, store from accumulator back to memory, multiply from memory to accumulator, copy from memory location to screen or disk, and so forth), and the address of the memory location to be used, called the "operand".

The total set of instructions that a computer is capable of (each type and model is different) is called the "Instruction Set" for the computer (technically, for the Central Processing Unit or CPU.) The more separate op codes a computer has in its Instruction Set, the more specifically it can carry out instructions, and the fewer instructions it needs to carry out to get a specific task done. However, having many op codes can mean that the microprocessor is very complicated, and therefore slower. (There used to be two divergent approaches - RISC or Reduced Instruction Set and CISC or Complex Instruction Set. RISC computers were supposed to be faster because it was felt that they could make up for needing to carry out more of their simpler instructions, by being much faster. However, this supposed advantage has not shown up in practice. It has also helped the CISCs that they have adopted many of the best ideas of the RISC advocates. The Intel Pentium processors are CISCs.)

How much storage room does a computer instruction occupy?
1. One factor is the number of different instructions that the CPU is capable of. Using the formula for the number of different values that can be stored in n bits, and knowing how many different op codes a given design needs, we can determine that part. For example, if a CPU is to have 64 op codes, we will need 6 bits. That may seem to be a large number of op codes, but many microprocessors have extra hardware such as Registers, that are capable of some arithmetic that can speed up operations on a series of numbers, and Interrupts that can handle critical events by taking the computer away from routine tasks. These features greatly increase the number of op codes needed, and some CPUs have hundreds and even thousands op codes, or more.
2. The second factor is the size of the address portion of the instruction. This determines the maximum number of storage spaces that the CPU can have connected. If the address is one byte, that CPU could only use 256 RAM locations. Set aside two bytes, and it can use 65,000+ locations. It is not uncommon today to have five bytes for the address, with a capacity of 10+ terrabytes or 10,000 gigabytes. The program is also stored in RAM, and so additional capacity is required here. The total memory requirement is the maximum number of storage for data (text, graphics, sound and numbers) plus the maximum size of a program in instructions. This maximum number is called the "address space" of the processor. (These days, programs are large enough so that they are loaded into memory only when they are needed. A "dll" extension in Windows is the extension for such a piece of a program.)
3. So, a CPU with 65,000+ op codes and 10 terrabytes of address space requires 2 bytes per instruction for the op code and 5 bytes per instruction for the address, or a total of 7 bytes of storage for each instruction. A program that is 1 million instructions long will require 7 × 1,000,000 bytes, or 7,000,000 bytes (7 MB). In general, (bytes per instruction) = (bytes for op codes) + (bytes for address) and (program size in bytes) = (size of instruction in bytes) × (size of program in instructions).
4. The operand usually has the address of the memory location to be used for data in the instruction. But the instructions themselves are also stored in RAM memory. There is another special type of memory that holds the address in memory for the next instruction. This is called the "Instruction Pointer" or IP.
5. The CPU executes instructions in a "Instruction Cycle":
  1. Fetch the next instruction from the memory location in the IP
  2. Decode or Interpret the instruction. The op code and the operand must be separated. Also, the computer has different circuits for addition, multiplication and other operations, and in this part of the cycle, the CPU identifies the circuit to be used for the current operation
  3. Execute or carry out the instruction
  4. Increment the IP to point to the next instruction. Instructions are usually executed serially - each time in the next highest memory location - but some instructions can modify the IP, changing the path of the program.
  5. Cycle back to the first part of the cycle and continue executing. Execution stops with a "Stop" instruction.
6. Some types of computer instructions:
  1. Addition / Subtraction
  2. Multiplication / Division
  3. Stop
  4. No operation (do nothing)
  5. Jump, or go to a specified memory location (not the next one), which means to put the address of the next instruction into the IP
  6. Compare the operand with the accumulator, and set indicators if the operand is greater than, equal to, or less than the accumulator
  7. Jump if, or go to a specified address that depends on the result of the last Compare
  8. Input and Output instructions

. Worksheet: Doing Binary Arithmetic With Switches.
More Windows basics - Windows Explorer and the hierarchical file system. Windows Explorer is the Windows tool of choice for managing files
1. Last week we used Drag 'N Drop to copy files. Today we will use Cut and Paste.
2. Open Windows (NT) Explorer (Start / Programs) and change its options to show all information
  1. Choose menu item View / Options and then the "View" tab at the top of the Options dialog
  2. Above the list box, make sure that "Show all files" is clicked
  3. Below the list box, make sure that "Display the full MS-DOS path in the title bar" is checked. This refers to the title bar on the right pane of Windows Explorer. If this is unchecked, Explorer shows only the final (lowest) folder name
  4. Make sure that "Hide MS_DOS file extensions for file types that are registered" is unchecked. Otherwise, Explorer does not show the file extension for most file names.
  5. Make sure that "Include description bar for right and left panes" is checked. Otherwise, Explorer does not show you what drives and folders you are looking at.
  6. Click OK. This puts your choices into effect.
3. Open the test floppy diskette in Windows (NT) Explorer. (Do this by clicking on the drive icon. Click on a file, then right click on it and choose "Copy." Go to another folder on the C: drive and right click on it, choosing "Paste" (was not available until you had something copied to the clipboard.
  1. This will also work with a selection of files.
  2. "Cut" will remove files from the original location, after they are pasted into the new location
  3. "Cut" can also work with Drag 'N Drop by holding down the <Alt> key.
  4. There are keyboard alternatives for Copy/Cut and Paste. <Ctrl>c and <Shift><Insert>do copy, <Ctrl>x and <Ctrl><Delete> do Cut, and <Ctrl>v and <Ctrl><Insert> do paste.
Topics for Midterm exam: (not final until the end of next class)
1. Computer hardware - what makes computers valuable?
  1. Types of computers (five)
  2. Diagram of a computer - input and output devices
  3. Types of storage - units - primary, secondary, differences, types of secondary storage
  4. Instruction cycle - Fetch, Interpret, Execute, Increment
  5. Accumulator - the place where the "computing" is done
  6. Some types of computer instructions
  7. Adding and multiplying with switches
2. Computer software
  1. Operating System - purpose
    1. User Interface - what is it?
      1. Command line
      2. GUI
    2. Windows
      1. Mouse actions
      2. Active parts of all windows - what you can do with them and how to do it
      3. Active elements - how to activate them
      4. Dialogs
      5. Wizards
      6. Multiple ways to accomplish the same thing
      7. Starting a program
        
        with a file open - two ways - differences
      8. Difference between Save and Save As...
      9. Drag 'N Drop Vs Cut/Copy and Paste
      10. Selection - methods and result
        
        Keyboard methods
        
        Mouse methods
  2. Applications - purpose, examples
  3. File system
    1. What is a file?
    2. Hierarchical file system, what can be in a folder
    3. Using Windows Explorer
    4. Path and URL - naming them, identifying and naming their parts
3. Forms of computer information
  1. ASCII codes - translating back and forth
  2. Number of values that can be stored in n bits
  3. File sizes for graphics, sound, number and program files
    1. Address space Vs actual memory size
4. Binary - counting, adding, multiplying, powers of 2 in binary and decimal, converting binary to decimal and decimal to binary
5. Applications
  1. Word processing
    1. Primary function and sub-functions of word processing - e.g. creating, editing, formatting, printing, saving, opening
    2. Using Word
  2. Spreadsheets
    1. Primary function and sub-functions of spreadsheet - e.g. storing numbers, storing text, formatting, formulae, charting, printing, saving, opening
    2. What can be in a cell
    3. Using Excel
  3. World Wide Web browser (Netscape or Internet Explorer)
    1. Going to a web site using
      1. Bookmark
      2. Typing in URL
      3. Using link
      4. Using history list
    2. Web chat
    3. Web computer conference
6. Using computers - Windows, Windows 95 Explorer, Word, Excel, and web browser
Lab 7. Read the following steps all the way through before starting.
1. Setting up your account for the course Chat and Computer Conference
  1. An account gives you a User name and Password
  2. If you have used the CLL Computer Conferencing System before in another course (Bowen, Richmond, Klein, Maruca), you can use that User Name and Password. You are done with this part of the Lab
  3. If you have not used this system before, then:
    1. Decide on your User Name and Password for this system
      User Name: _____________________
      Password: _____________________
    2. Start a web browser (Netscape or Internet Explorer)
    3. Got to the course web site at http://www.cll.wayne.edu/isp/drbowen/casw01
    4. Scroll down to the section on "Online Tools"
    5. Find and follow (click on) the link "Course computer conference"
    6. A gray box will pop up. Type in your User Name and Password and click "OK"
    7. If you see "Log in as a new user?", then click on "Yes, I am entering as a new user."
      [If you do NOT see "Log in as a new user?", then
      1. Close (Exit) the web browser
      2. Pick another User Name and/or Password
      3. Repeat, starting at B above]
    8. A web form will display. Fill in your information, making sure to include all of the red-bulleted items (these are required). The other items are not required.
    9. Scroll down and find the "Create" button. You will not need the User Number information on this page. You are done for tonight; close your web browser.
2. In New Perspectives On Microsoft Office 2000 Professional, do Excel Tutorial 2 on pages EXCEL 2.1 through EXCEL 2.44. The lab assignment is to create, edit, save and print out the file MSI Sales Report.xls according the the directions throughout the Tutorial - in other words, start at the beginning of the tutorial and work your way through it. No other part of this tutorial is assigned.
3. There is no download for this lab; you create the file from the beginning
4. Do NOT save the file to the location given in the book. Save it to your floppy diskette instead.
  REMINDER: being able to control where you save your files to is part of this course! Make sure you can do this without looking at a book or notes! So is starting Excel.
5. When you are done, make a title sheet using Word, with (a) your name, and (b) what assignment this is (Lab 7), print out a copy of your edited file, staple the pages together, and turn in this copy, by the start of the next class. This, together with your chat / computer conference account, is your lab report. You can print the spreadsheet using either:
  1. The printer icon on the toolbar
  2. The menu item File / Print, then click OK on the "Print" dialog.

Assignment 7. Please write or type "Assignment 7" on the work you turn in for this assignment.

Do the homework problem on the Worksheet.
If a computer is to have an address space of 16 bits and have 256 different instructions, how long are its instructions?
For the computer above, how many bytes would a program that is 100,000 instruction long take to store?
In Computers, Technology, and Society, answer the following Review questions on Pp 7-28 and following: 2, 3, 5, 6, 11 and 12.