Difference between revisions of "CSC231 Homework 7 Fall 2012"

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(Problem #2)
(Problem #2)
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Your program will contain the following 3 strings and should decode them and print them.
 
Your program will contain the following 3 strings and should decode them and print them.
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 +
 +
xLen    dd    18
 +
x        dd    0xd1, 0x41, 0xd5, 0x03, 0x81, 0xee, 0x5c, 0x0d,
 +
        dd    0x55, 0x40, 0x21, 0x40, 0xd1, 0xe0, 0x9e, 0x0c, 0x9d, 0x10

Revision as of 13:13, 24 October 2012

--D. Thiebaut 13:47, 24 October 2012 (EDT)


This assignment is due the evening of Oct. 31st, at midnight (booo!). You can work on this assignment in pairs.

Problem #1

Write a program that displays the contents of a double-word in hexadecimal. Your program should store the value 0x1234ABCD in a variable called x and should display this information:

  x = 305441741 = 0x1234ABCD


Submission

Submit your program (called hw7a.asm) as follows:

 rsubmit hw7 hw7a.asm

Problem #2

Take a look at the section of the ASCII table below:


ASCIIUpperCase.png


Concentrate on the hexadecimal code for each letter. You will notice that 'A' through 'O' have the same upper nybble. 'A' is 0x41 and 'O' is 0x4F. So, if I wanted to squeeze a string made of upper-case letters between 'A' and 'O', I would only need to store the lower nybble, and I'd save some memory.

The purpose of this problem is for you to take a string created using this method, decode it, and print it on the screen.

Your program will contain the following 3 strings and should decode them and print them.


xLen     dd     18
x        dd     0xd1, 0x41, 0xd5, 0x03, 0x81, 0xee, 0x5c, 0x0d, 
        dd     0x55, 0x40, 0x21, 0x40, 0xd1, 0xe0, 0x9e, 0x0c, 0x9d, 0x10