Difference between revisions of "CSC231 Homework 2"
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What hexadecimal values are stored in the registers '''eax''', '''ebx''', '''ecx''', and '''edx''' when the processor has reached the 3rd NOP instruction of the program? | What hexadecimal values are stored in the registers '''eax''', '''ebx''', '''ecx''', and '''edx''' when the processor has reached the 3rd NOP instruction of the program? | ||
| − | Write your answers in a file called hw2.txt and submit your file as follows: | + | Write your answers in a file called''' hw2.txt''' and submit your file as follows: |
submit hw2 hw2.txt | submit hw2 hw2.txt | ||
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Assignment #2
This assignment is due on Wednesday, Sept 24th, at 11:59 p.m. plus 1 minute.
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 transfering the program, debug it:
ddd hw2 &
Question 1
What string of characters is contained in the array that occupies the first 31 bytes of memory when the processor has reached the 3rd NOP instruction of the program?
Question 2
What hexadecimal values are stored in the registers eax, ebx, ecx, and edx when the processor has reached the 3rd NOP instruction of the program?
Write your answers in a file called hw2.txt and submit your file as follows:
submit hw2 hw2.txt
