CS 5513 Fall 2009, Homework 1

1. Write an original essay on a topic of interest to you that is not related to computers or information technology. It should be about 500 words. Use an editor or word processor.

2. Consider the following sequence of hexadecimal values:

   
   86 01 
   8E 10 02 
   A7 80 
   8C 20 00 
   26 F9 
   86 02 
   1F 89 
   58 
   8E 00 00 
   3A 
   6F 89 10 00 
   30 86 
   8C 10 00 
   25 F5 
   4C 
   81 40 
   26 E9 
   7F 10 00 
   7F 10 01 
   39
   

   This sequence of hexadecimal bytes represents a subroutine in MC6809 machine language. The code is position-independent; you may assume that it is located anywhere in memory where it will not write to itself. For your convenience, the bytes have been separated into lines representing one machine instruction each.
   • When the instructions in this subroutine are executed, they affect memory from 0x1000 to 0x1fff. In one brief sentence, characterize this effect on memory.
   • Write a program in C, C++, or Java that carries out the computation done by this subroutine, then prints the values in memory locations 0x1000 through 0x1fff computed by your program of as they would appear at the end of the execution of the subroutine. Turn in this code as part of your writeup.
   • (Extra credit) What is the name of the computation being carried out by the subroutine?

     Note: It is expected that most students are not familiar with MC6809 machine language. You are expected to be resourceful. Find information and possibly tools on the Internet to help you with this problem. There is more than one right way to do this assignment.

Your assignment should be nicely typed or word-processed. Turn in this assignment at the beginning of class on September 10, 2009. You must turn in the assignment on paper at the beginning of class.

Late assignments will not be accepted.