Difference between revisions of "CSC231 Homework 2"

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(Problem #2)
(Question 1)
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===Question 1===
 
===Question 1===
  
What string of characters is contained in the string that occupies the first 31 bytes of memory?
+
What string of characters is contained in the array that occupies the first 31 bytes of memory?
  
 
===Question 2===
 
===Question 2===
  
 
What is in the registers eax, ebx, ecx, and edx when the processor has reached the 3rd NOP instruction of the program?
 
What is in the registers eax, ebx, ecx, and edx when the processor has reached the 3rd NOP instruction of the program?

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Assignment #2

Problem #1

Write a program that displays the following patter using loops.

**********#
 *********##
  ********###
   *******####
    ******#####
     *****######
      ****#######
       ***########
        **#########
         *##########
        **#########
       ***########
      ****#######
     *****######
    ******#####
   *******####
  ********###
 *********##
**********#

Requirements: your program cannot contain more than 5 int 0x80 instructions!

Store your program in a file called hw2a.asm and submit it as follows:

  submit hw2 hw2a.asm

Problem #2

For this problem you have to debug the executable version of a program and answer two questions.

You can get the executable version of the program by using this command, from your Linux account:

   cp ~thiebaut/public_html/classes/231/hw2   .

(don't forget the dot at the end of the line!)

If you are working off-campus, and you have a linux machine where the utility wget is installed, try this:

   wget http://cs.smith.edu/~thiebaut/classes/231/hw2

And you should get a copy of the program.

Once you're done, debug the program:

   ddd hw2 &


Question 1

What string of characters is contained in the array that occupies the first 31 bytes of memory?

Question 2

What is in the registers eax, ebx, ecx, and edx when the processor has reached the 3rd NOP instruction of the program?