Cpre 288 Homework

CprE 288 Fall 2017 Homework 5 (Solutions) �Due: Not turned in or Graded Notes: . Homework must be typed and submitted as a PDF or Word Document (i.e. .doc or .docx) only. . If collaborating with others, you must document who you collaborate with, and specify in what way you collaborated (see last page of homework assignment), review the homeworkpolicy section of the syllabus: http://class.ece.iastate.edu/cpre288/syllabus.asp for further details. . Review University policy relating to the integrity of scholarship. See (Academic Dishonesty): ��http://catalog.iastate.edu/academic_conduct/#academicdishonestytext . Late homework is accepted within two days from the due date. Late penalty is 10% per day. Except on Exam weeks, homework only accepted 1 day late. . Note: Code that will not compile is a typo. Answering a question as will not �compilewill be �marked incorrect. Contact the Professor if you think you have found a typo. Note: Unless otherwise specified, all problems assume the TM4C123 is being used Question 1: Volatile keyword (5 pts) When developing software for an embedded system, the keyword volatile is often used. Read through the articles below and answer the following: Jones, Nigel. "Introduction to the Volatile Keyword" Embedded Systems Programming, July 2001: http://www.embedded.com/electronics-blogs/beginner-s-corner/4023801/Introduction-to-the-Volatile-Keyword Wikipedia Article: https://en.wikipedia.org/wiki/Volatile_(computer_programming)a) Give a summary of the conditions under which the volatile keyword should be used within a C based embedded system, and why. In general the keyword volatile is used for a variable when its value can changein a manner for which the compiler cannot track. Specific examples:

Initials: ________ 1 CprE 288 Introduction to Embedded Systems Fall 2015 Exam 2 Last Name (printed) _________________________ First Name (printed) _________________________ Lab Section _________________________ Instructions:  Do not open this exam booklet until told to do so.  Do not disclose the content of this exam or get any knowledge about it outside the exam. Report to the professors/TAs if you know about any such activity.  Open book, open notes.  Calculator allowed.  Do all work in the space provided. You must show your work to receive credit.  Clearly indicate the answer you want counted.  Make assumptions if necessary to work problems.  Unless a question asks if a line of C code is valid, then any question for which code will not compile is due to a typo, bring this to the instructor’s attention. Answering a question based on the reasoning that code will not compile will not receive credit.  Be sure to complete the three lines above.  Cheating will not be tolerated by the instructor or your classmates and will result in a severe penalty.  This is a 75-minute exam. Score: Q1 Q2 Q3 Q4 Q5 Total 12 12 12 12 12 60 NOTEs:  All questions are regarding the ATmega128 microcontroller and the AVR Studio platform unless stated otherwise. You may assume <avr/io.h> is included.  You must use a good programming style, e.g. meaningful variable names, appropriate comment and consistent indentation. Additionally, your code should be as efficient as possible. You must use standard C.  C code with poor programming style or bad run-time efficiency may receive partial credit.

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *