课程名称︰嵌入式作业系统实作
课程性质︰选修
课程教师︰薛智文
开课学院：电资学院
开课系所︰资工所、网媒所
考试日期（年月日）︰2015.04.21 上课时(14:20pm)公布考题,
2015.04.22 中午前(11:59am)缴交
考试时限（分钟）：
试题 :
This is a take-home exam. Add more assumption for the questions if you need.
Please do answer with your OWN SUCCINCT words after each question
(keep the question) in this file in less than 5 pages of the same text font
(Times New Roman 12). You can turn in with another file format of the similar
look. You can answer in Chinese or English. Please send your file back to
cwhsueh@csie.ntu.edu.tw with a new filename of your ID by April 22th 11:59AM.
We will decide your order for project presentation (less than 20 minutes) in
next class at 111 by that the earlier one with receive time of the last
submission of this midterm in your group has higher priority. Have fun.
1. [10%] When we burn u-boot on PXA270, why we need to copy twice?
2. [20%] In homework, for the uC/OSII on DOS, if we run the given TEST.exe
several instances simultaneously, the timer in each instance will have more
and more difference as time goes by. Why and how do we fix this problem to
shorten the time drift?
3. [30%] Suppose we would like to write a stopwatch (user) program on Creator
PXA270 by the given driver as Lab 2. It needs to support variable precision
ranging from one millisecond to one second, where the decimal point is not
shown for one-second resolution. The driver does not support a decimal digit
on the 4-digit 7-segment LED, please describe how the LED and keyboard
button works, and how to extend the driver to implement the stopwatch. Your
solution should be backward compatible, extendable (no secret of driver is
revealed), compact and as accurate as possible. No codes are needed. The
suggestion in class might not be correct.
4. [20%] uCOS is a real-time OS with O(1) scheduler, where the task with the
highest priority can be identified at constant time. In addition to the
ready "queue" for scheduling, the O(1) mechanism are also applied in other
uCOS components. Please describe the disadvantages of the O(1) mechanism,
and which components mentioned above can be released NOT to use the O(1)
mechanism.
5. [15%] To implement an embedded system, we need to take care of software
components in BSP (board support package), bootloader, OS, driver, tool
chain, and the application. For Taiwan embedded software industry, which
components are the most valuable you would like to explore? Why? Please
give examples and describe how to accomplish the value you expect and how
many man months it might take.
6. [5%] What is your job in your term project? What is the most valuable
contribution of your term project in terms of the system problems to solve?