Assignment 1

CS/ECE 354-2, Fall 1998

due Monday Sept. 28, before 5pm

Program

Purpose

This program is intended to provide experience in dealing with the computer's variety of data representations.

Program Statement

Write a SASM program that reads in a single positive integer, and prints it back out in hexadecimal.

A sample execution of the program looks like


Enter an integer (>0): 26
The value in hexadecimal: 1a


Requirements

  1. Your program must contain adequate comments (documentation). Such comments include your name and section number at the top of the program. They also include a description of the program, as well as variable descriptions and comments about the code itself.
  2. For this program, an integer consists of only the characters '0'-'9', and is immediately followed by the newline character (0ah). Any other input is considered bad. For the case of bad input, your program should print out an error message indicating bad input and then exit. Note that leading zeros must be handled correctly, since they are included (by this definition) as good input.

    Handing In the Program

    Follow the guidelines in how to turn in assignments. For this program, you will need to turn in your source code (the .asm extension) and your makefile (the .mak extension). No printout will be turned in.


    Homework (25 points)

    1. (4 points)
      (a) Convert the base 6 value 204 to base 4.
      (b) Convert the base 4 value 310021.201 to base 2 (binary).
      (c) Convert the base 8 value 615.201 to base 16 (hexadecimal).
      (d) Convert the base 2 value 11001101 to base 10 (decimal).
    2. (9 points)
      Give 8-bit representations to fill in the following table.
      decimal     sign magnitude     two's complement     biased-127
      
        13
      
        -2
      
        185
      
    3. (4 points)
      What string is represented by the SASM declaration
      
      a_str  dd 52656164h
             dd 79210000h
      
      
    4. (5 points)
      What is the IEEE single precision floating point representation for the decimal number -22.25? Give the result in binary and in hexadecimal.
    5. (3 points)
      What decimal value is represented by the IEEE single precision representation, given in hexadecimal by 0xc4800000?

      Handing In the Homework

      Follow the guidelines in how to turn in assignments. For this homework, you will need to turn in a single file containing your answers to the homework questions. To make grading easier, please name your file hw1.txt. No printout will be turned in.