Program #5 base-indexed addressing

Program #5

Objectives
1. Using indirect addressing and/or base-indexed addressing
2. Passing parameters on the stack
3. Generating “random” numbers
4. Working with arrays
Description
Write a MASM program to perform the tasks shown below. Be sure to test your program and ensure that it rejects incorrect input values.
1. Introduce the program.
2. Get a user request in the range [min = 15 .. max = 200].
3. Generate request random integers in the range [lo = 100 .. hi = 999], storing them in consecutive elements of an array.
4. Display the list of integers before sorting, 10 numbers per line.
5. Sort the list in descending order (i.e., largest first).
6. Calculate and display the median value, rounded to the nearest integer.
7. Display the sorted list, 10 numbers per line.
Example Program Operation
Sorting Random Integers
Programmed by Author Name
This program generates random numbers in the range [100 .. 999],
displays the original list, sorts the list, and calculates the
median value. Finally, it displays the list sorted in descending order.
How many numbers should be generated? [15 .. 200]: 10
Invalid input
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How many numbers should be generated? [15 .. 200]: 16
The unsorted random numbers:
680 329 279 846 123 101 427 913 255 736
431 545 984 391 626 803
The median is 488.
The sorted list:
984 913 846 803 736 680 626 545 431 427
391 329 279 255 123 101
Thanks for using my program!
Requirements
1. The title, programmer's name, and brief instructions must be displayed on the screen.
2. The program must validate the user’s request.
3. The main procedure must consist (mostly) of procedure calls. It should be a readable “list” of what the program will do.
4. min, max, lo, and hi must be declared and used as global constants.
5. All procedure parameters must be passed on the system stack.
6. Each procedure will implement a section of the program logic, i.e., each procedure will specify how the logic of its section is
implemented. The program must be modularized into at least the following procedures and sub-procedures:
main
introduction
get data {parameters: request (reference)}
fill array {parameters: request (value), array (reference)}
sort list {parameters: array (reference), request (value)}
exchange elements (for most sorting algorithms): {parameters: array[i] (reference), array[j] (reference), where i and j are the
indices of elements to be exchanged}
display median {parameters: array (reference), request (value)}
display list {parameters: array (reference), request (value), title (reference)}
7. Parameters must be passed by value or by reference on the system stack as listed above.
8. There must be just one procedure to display the list. This procedure must be called twice: once to display the unsorted list, and once to
display the sorted list.
9. Procedures (except main) should not reference .data segment variables by name. request, array, and titles for the sorted/unsorted lists
should be declared in the .data segment, but procedures must use them as parameters. Procedures are allowed to use local variables
when appropriate (section 8.2.9 in the textbook). Global constants are OK.
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10. The program must use appropriate addressing modes for array elements.
11. The two lists must be identified when they are displayed (use the title parameter for the display procedure).
12. Each procedure must have a procedure header that follows the format discussed during lecture.
13. The code and the output must be well-formatted.
14. The usual requirements regarding documentation, readability, user-friendliness, etc., apply.
Notes
1. DO NOT put this off - it is a much more time-intensive project than any of Programs #1 - #4.
2. The Irvine library provides procedures for generating random numbers. Call Randomize once at the beginning of the program (to set
up so you don't get the same sequence every time), and call RandomRange to get a pseudo-random number. (See the documentation
in Lecture slides.)
3. The Selection Sort is probably the easiest sorting algorithm to implement. Here is a version of the descending order algorithm, where
request is the number of array elements being sorted, and exchange is the code to exchange two elements of an array:
for (k=0; k<request-1; k++) {
 i = k;
 for (j=k+1; j<request; j++) {
 if (array[j] > array[i])
 i = j;
 }
 exchange(array[k], array[i]);
}
4. The median is calculated after the array is sorted. It is the "middle" element of the sorted list. If the number of elements is even, the
median is the average of the middle two elements (may be rounded).
5. If you choose to use the LOCAL directive while working on this program be sure to read section 8.2.9 in the Irvine textbook. LOCAL
variables will affect the contents of the system stack!
Extra Credit Options
(0.5 pt) Add a greeting message that contains EXACTLY ONE TA name at the beginning of the program. If that TA happens to be your
grader, then you get the points :)
(1 pt) Display the numbers ordered by column instead of by row.
(3 pts) Implement the sorting functionality using a recursive Merge Sort algorithm. For a graphical explanation of the algorithm, I
recommend this GeeksForGeeks article (https://www.geeksforgeeks.org/merge-sort/) . You may add additional procedures to your
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Program 5 Rubric
program as needed. Remember that all parameters must be passed on the system stack.
In order to ensure you receive credit for any extra credit work, you must add one print statement to your program output PER EXTRA
CREDIT which describes the extra credit you chose to work on. You will not receive extra credit points unless you do this. The statement
must be formatted as follows...
--Program Intro--
**EC: DESCRIPTION
--Program prompts, etc--
Please refer back to the documentation for Program 1 to see a sample of the extra credit format.
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Criteria Ratings Pts
1 pts
1 pts
1 pts
1 pts
2 pts
Files Correctly Submitted
Submitted file is correct assignment and is an individual .asm file.
1 pts
Full Marks
0 pts
No Marks
Program Assembles & Links
Submitted program assembles and links without need for clarifying work for TA and/or
messages to the student. This assumes the program is actually an attempt at the
assignment. Non-attempts which compile/link earn no points.
1 pts
Full Marks
0 pts
No Marks
Documentation - Identification Block - Header
Name, Date, Program number, etc as per syllabus are included in Identification Block
1 pts
Full Marks
0 pts
No Marks
Documentation - Identification Block - Program Description
Description of functionality and purpose of program is included in identification block.
1 pts
Full Marks
0 pts
No Marks
Documentation - Procedure Headers
Procedure headers describe functionality and implementation of program flow. Should
also list pre- and post-conditions and registers changed.
2 pts
Full
Marks
1 pts
Headers without Conditions
Descriptive headers but lacking preand post-conditions and 'registers
changed'
0 pts
No
Marks
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Criteria Ratings Pts
1 pts
2 pts
1 pts
1 pts
2 pts
1 pts
Documentation - In-line Comments
In-line comments contribute to understanding of program flow (from section comments)
but are not line-by-line descriptions of moving memory to registers.
1 pts
Full Marks
0 pts
No Marks
Program Executes
Program executes and makes some attempt at the assigned functionality.
2 pts
Full Marks
0 pts
No Marks
Completeness - Displays Title & Programmer Name
Program prints out the programmer's name and Program Title
1 pts
Full Marks
0 pts
No Marks
Completeness - Displays Introduction
Displays program introduction. Program introduction should describe functionality of
program.
1 pts
Full Marks
0 pts
No Marks
Completeness - Gets / Validates data from User
Utilizes ReadInt or ReadDec to receive user input. Saves values in appropriately-named
identifiers for validation. | Validates that user-entered values are within the advertised
limits.
2 pts
Full Marks
0 pts
No Marks
Completeness - Displays Unsorted List 1 pts
Full Marks
0 pts
No Marks
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Criteria Ratings Pts
1 pts
1 pts
1 pts
1 pts
1 pts
2 pts
2 pts
Completeness - Displays Median 1 pts
Full Marks
0 pts
No Marks
Completeness - Displays Sorted List 1 pts
Full Marks
0 pts
No Marks
Completeness - Lists are displayed 10 numbers per line 1 pts
Full Marks
0 pts
No Marks
Completeness - Lists are labeled "unsorted" and "sorted" 1 pts
Full Marks
0 pts
No Marks
Correctness - Array declaration
List array declared as 200 integers
1 pts
Full Marks
0 pts
No Marks
Correctness - Random Number Generation
Generates random numbers correctly in range
2 pts
Full Marks
0 pts
No Marks
Correctness - Fill Array
Stores random numbers consecutively in array
2 pts
Full Marks
0 pts
No Marks
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Criteria Ratings Pts
5 pts
2 pts
8 pts
5 pts
2 pts
Correctness - List is sorted in descending order 5 pts
Full
Marks
3 pts
Ascending order
List is sorted in ascending (instead
of descending) order
0 pts
No
Marks
Correctness - Median Calculation
Correctly calculates and rounds median
2 pts
Full Marks
0 pts
No Marks
Requirements - Modular Design
Uses procedures: main, introduction, getData, fillArray, sortList, displayMedian,
displayList
8 pts
Full
Marks
6 pts
All except median
All procedures exist and used
except displayMedian. Median
calculation done in main or grouped
in other procedure.
0 pts
No
Marks
Requirements - Parameter Passing
All parameters are passed to procedures on the system stack (arrays, strings, and return
values by OFFSET; others by value)
5 pts
Full
Marks
3 pts
All but strings
Value-parameters and return
parameters passed on stack but
array/string offsets are not.
0 pts
No
Marks
Requirements - displayList correctly used
Two different CALLs to the same displayList procedure (one for the unsorted list, one for
the sorted). If there are two different list display procedures - zero points
2 pts
Full Marks
0 pts
No Marks
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Criteria Ratings Pts
2 pts
0 pts
0 pts
1 pts
1 pts
1 pts
Requirements - Limits as CONSTANTS
Random range bounds and user input bounds are declared and used as constants.
2 pts
Full Marks
0 pts
No Marks
Requirements - No non-CONSTANT global references outside of main
Deduct 5 points if there are any non-CONSTANT global references outside of MAIN
0 pts
Full Marks
0 pts
No Marks
Requirements - Correct Array Addressing Modes
Deduct 5 points if indirect addressing (register as pointer) or base-index is not used for
array processing.
0 pts
Full Marks
0 pts
No Marks
Coding Style - Uses appropriately named identifiers
Identifiers named so that a person reading the code can intuit the purpose of a variable,
constant, or label just by reading its name.
1 pts
Full Marks
0 pts
No Marks
Coding Style - Readability
Program uses readable white-space, indentation, and spacing as per the Indentation
Style Guide. Logical sections are separated by white space.
1 pts
Full Marks
0 pts
No Marks
Output Style - Readability
Program output is easy to read
1 pts
Full Marks
0 pts
No Marks
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Total Points: 50
Criteria Ratings Pts
0 pts
0 pts
Extra Credit
Successfully guess the grader (0.5 pts)
Displays the numbers ordered by column instead of by row (1 pt)
Implements recursive merge sort algorithm (3 pts)
0 pts
Full Marks
0 pts
No Marks
Late Penalty
Remove points here for late assignments. (Enter negative point value)
0 pts
Full Marks
0 pts
No Marks
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