CSC3210 Assignment 3 Solution

Objective: Learn memory organization/layout, data transfer concepts and instructions, direct memory access, memory allocation.

Requirements:
1. (5 points) Write an assembly program to compute the following expressions

- Create a DWORD array named ‘z’ of size 3 using DUP operator. Leave the array ‘z’ uninitialized. You can denote the items in the array as [𝑧!, 𝑧", 𝑧#], where 𝑧! is the first item, 𝑧" is the second item,
𝑧# is the third item
- Update each array item using the following expressions.

𝑧! = 𝑥 + 130
𝑧" = 𝑦 + 𝑥 − 𝑧!
𝑧# = 𝑟 + 𝑥 − 13


- Where x, y, r are 16-bit integer memory variables.
- x = 10, y = 15, r = 4
- Use mov, movzx, movsx, add, sub instructions only.
- (hint: Do not alter the value of x, y and r during the computation. Transfer them to appropriate registers to do computation)
- At the end, open memory window to see the variable z stored in memory (little endian format). - If you code correctly, 𝑧! = 140 in decimal, 𝑧" = −115 in decimal, 𝑧# = 1 in decimal
- Use the debugger to verify your answer.
o Submit the following:
§ Rename the asm file using your last name as Lastname1.asm
§ Screenshot of the code and memory window showing the content of the variable z (little endian format).


2. (5 points) Use a loop instruction with indirect addressing to solve the problem.
- Do not copy the elements to any other array.
- Use the LOOP and XCHG instruction.
- The input array, inputStr contains elements: “A”, “B”, “C”, “D”, “E”, “F”, “G”, “H”.
- The array’s elements after running the program should look like: “H”, “G”, “F”, “E”, “D”, “C”, “B”, “A”.
o Submit the following:
§ Rename the asm file using your last name as Lastname2.asm
§ Screenshot of the code and memory window showing the content of the variable inputStr.


3. (5 points) Write an assembly program that does the following:
- Define the following value 0506030704080102h in the .data segment using the 64-bit unsigned identifier named qVal.
- You can subdivide the qVal value into 4 words – 0506, 0307, 4080, 0102 - Extract these words from qVal using PTR operator.
- Find the sum of the words. The sum should be D17h.
- Store the result in any 16-bit register.
- The direction of adding two words goes from left to right.
o Submit the following:
§ Rename the asm file using your last name as Lastname3.asm
§ Screenshot of the code and memory window showing the result in a 16-bit register.





Note:
§ Comment header for .ASM files:
Student: Full name
Class: CSC3210
Assignment#: 3
Description: This program ………….
§ Follow the program standards as presented in your book. Pay more attention to code comments and consistent indentation.
§ Create a new project for every question. Do not use one project with multiple .asm files.