COP-3402 Information

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• What's New
  • Using Indirect References
  • Here is my entry for the phrase to remember the range for 32-bit numbers
    What is happening when everyone's simply waiting to encounter truth?
  • Machine Code Instructions
  • Floating Point Numbers
  • Passing Parameters on the Run Time Stack
  • Accessing a two-dimensional array
  • Hamming Code
• Assignments
  • Submitting homework on-line
  • Assignment 1.
    • Due to the holiday on 1/17, I have changed the due date for Monday's section to 1/26. The due date for Tuesday's section has not changed.
    • Option 4 of the menu should display EVEN numbers above the average.
    • Do not use recursion for this assignment.
    • Read a character to pause.
    • Do not bother about centering the text, nor clearing the screen.
    • Run an example of the homework assignment.
    • In the assignment, 'print' means 'display on the screen'. Do not send any program output to the printer.
  • Assignment 2.
  • Assignment 3.
    • You must download a copy of ASM_IO.INC to the directory where your ASM file is located.
  • Assignment 4
    • The pause procedure may reference the name of the string for the message from the data segment.
    • The rowDir array in the homework assignment had an incorrect value in it. The final 3, in the 14th position, should be a -3:

      rowDir   db  0, 1,-2,-1, 1,-1, 1, 2,-2,-3,-2,-2, 0,-3, 0
      
      

  • Assignment 5
    • If you obtained a copy of the assignment before 12 noon on 3/16, then get a new copy. I have added two functions.
    • The recursion acts like this:
      If the first character is 0dh, then return without doing anything. Otherwise, push the first character onto the stack so you can get it later and call the function with a string that is one letter shorter. When the call returns, print the character that is on the stack.
  • Assignment 6
    • If you obtained a copy of the assignment before 1:30 pm on 4/5, then get a new copy. I have added  more problems.
    • Please note that FSUB subtracts the top of the stack FROM the second element on the stack, not the other way around. I gave section 04 the wrong information.
    • For the Hamming code questions, please use an even parity.
• Running MASM
  • Running MASM in an IDE, updated with Visual Studio commands.
  • I have updated the link for Configuring MASM 6.11 from your home computer. In particular, the device= statements. This version of MASM has placed two of the files in the BINR directory, that is why you are getting the "Device Driver Not Found" errors. Please check the page again for the new statements.
  • I have updated the link for Running MASM to include instructions for running MASM from your home computer.
  • If you are using Notepad to create your .ASM file, then you must save the file using double quotes. For instance, if the name of your file is first.asm, then save it as "first.asm". This will prevent the addition of the .txt extension.
• Exam Information
  • Sections covered for the midterm.
  • Guaranteed Topics on the midterm
  • Sections covered for the final
• Additional Topics
  • Multilevel Computers
  • Hamming Code
  • Big Endian versus Little Endian
  • How big is a gigabyte? Some examples of the sizes of things.
  • Explanation of prefixes. Kilo, Mega, Giga, then what?
  • Pipelining
  • Branch Prediction
  • Superscalar
  • Cache
  • Analog to Digital. Listen to a discussion from NPR about analog and digital technologies.
  • Calculating a 20-bit address
  • An example for a symbol table
  • Reading the output of the TRACE command in debug
  • A great page for memory information
    • Information about memory sizes and parity
    • Memory technologies
    • Memory Speed and Access Timing
    • Video RAM
    • Memory Technology Types
  • Types of memory
  • Types of interrupts
• Programming in MASM 6.11
  • Running MASM
  • Examples from the text book
  • Book's Web Page
  • Header to include in all programs
  • Necessary comments in all programs
  • Some deductions from programs
  • What to hand in
  • MASM 6.11
  • Programmer's Workbench and CodeView Information, Creating and debugging assembler programs.
  • Simplified segment definition template for creating an Assembler program
  • Configuring MASM 6.11 from your home computer
• Course Information
  • Syllabi
    • Section 03, TR 12:30
    • Section 04, MW 6:25

Examples of how I like code to be written

• Rewrite of the example on page 142 of the text
• Rewrite of the example on page 145 of the text

MASM 6.11

We will be using the Microsoft Assembler, MASM 6.11, in this course. It has been installed in the PC411 and in the AUL (ECS 241).

For those of you with computers at home, the text book for the course comes with a copy of MASM 6.11. The installation requires at least 4MB of RAM. Some students have had difficulty installing it, so read the documentation and follow the instructions closely. Configuring MASM 6.11 from your home computer.

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Header to include in all programs

You are to include the following comment at the start of each program that you hand in, and then SIGN the statement.

; Name: your name
; File Name: the name of the file that contains your source code
;
; Program Description: Several sentences that give a complete description
; of your program.
;
; Instructor: Tim Downey        Class: COP3402  Section: your section
;
; I attest that I have done this assignment without help from other people,
; except possibly Tim Downey.
;
; Signed: sign your name here
;

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Necessary comments to include in all programs

• A comment before each procedure, explaining what the procedure does, and which registers and global variables are changed by it
• The header stating that all this work is your own
• Comments on lines that help explain the program. It is not neccessary to comment each line. Place enough comments to document what (you think) you are doing.
• You should include enough comments so that I can read just the comments and understand completely what your program does.

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Some decuctions from programs

• Insufficient comments
• Bad names for variables, procedures and labels
• NEVER jump out of a procedure, always return from one.
• Insufficient use of EQU statements

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What to hand in

For each assignment you are to hand in the following

• Upload a copy of your .asm file. Follow these instructions: Uploading via the Web.
• Hand in a printout of the source file (.asm)

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Steps to create a project

• From the Project menu, select New Project
• Give the project a name. DO NOT INCLUDE AN EXTENSION
• Choose the option Set project template
• For runtime support, select None
• For Project Template, select DOS EXE
• Select OK, then select OK again

You should now be at a screen that shows you all the files in your directory. You will now select the particular files you want in your project.

• Select the main module, for example MAIN.ASM, from the upper list, then click on Add
• Select any other modules, for example MOD.ASM, from the upper list, then click on Add
• Continue this process for all the files you want in your project
• When you are done, click on Save List

You now have a project for the indicated files.

• To create the final executable, click on Build under the project menu. It should indicate the name of your project with a .EXE extension, for example Build PROJ.EXE.
• In the future, when you want to work on the project, you must first Open the project under the Project menu. When you open the project, look for a file withe the name of your project, with the extension MAK, for example PROJ.MAK

Example of two files that could be combined together in a project

• Main program
• Procedure module

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Reading and Printing Decimal Numbers

I have created four routines that you can use that read and print decimal numbers.

Reading a decimal

To read a decimal, call the routine READ_SIGNED or READ_UNSIGNED. After the call, the AX register will contain the decimal number stored in hexadecimal.

call READ_SIGNED
;now AX has the number

or

call READ_UNSIGNED
;now AX has the number

Printing a number in decimal format

To print a number in decimal, place the number in AX, then call the routine PRINT_SIGNED or PRINT_UNSIGNED. The routine will take the number that is stored in AX, and print it in decimal format. Warning: this routine will destroy the contents of AX.

mov AX, TOTAL
call PRINT_SIGNED

or

mov AX, TOTAL
call PRINT_UNSIGNED

To get this to work, just include the file ASM_IO.INC just after the .code statement and before the start of the program

	.code
include	asm_io.inc
main 	proc
	mov	ax,@data
	...

You will need to download the file ASM_IO.INC and place it in the same directory as your source code. Here is a link to the code for ASM_IO.INC. Follow this link in your browser, then click on File, Save As to download it. Save it in the same directory as your ASM file. If your browser tries to download it as an HTML file, then cancel the operation and do the following

• From the browser window that is displaying the contents of the ASM_IO.INC file, press CTRL-A. This will highlight the contents of the page.
• Press CTRL-C. This will copy the contents of the page.
• Open Notepad on your computer. In the blank Notepad screen press CTRL-V. This will copy the contents of the ASM_IO.INC file into Notepad. Save the file as "ASM_IO.INC". Be sure to include the double-quotes around the name, or Notepad will append a .txt to the name. Save the file in the same directory as your ASM file.

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Types of Interrupts

10h	Video
13h	Disk
14h	Serial Port
15h	I/O Subsytem (eg, Joystick)
16h	Keyboard
17h	Parallel Port Printer
1Ah	Real-time clock
21h	DOS
33h	Mouse

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