CS 686

PROJECT #1                                  Due: 7:30pm Tuesday 03/20/07

     This project explores the concept of "console redirection" and asks
the student to implement some interrupt-handlers that will execute using 
Intel's Extended Memory 64-bit Technology (i.e., 64-bit mode).  


                           PROBLEM STATEMENT

     Write an assembly language program (named 'useisr64.s') that allows
a user to watch a dynamically updated display of the current time-of-day
for at least fifteen seconds while executing on our Core-2 Duo platforms
in IA-32e mode.  Your program will need to employ interrupt-handlers for
both the timer-tick interrupts and the serial-UART's THRE-interrupts, so
that time-keeping is kept current and the screen-display remains visible 
during your program's execution.  Your program must begin executing from
'real-mode', must make the transition to IA-32e mode, and must return to
real-mode at the conclusion of its execution.  And, in order that it can
be loaded from the hard-disk's partition (i.e., device-file '/dev/sda4')
using our 'cs686ipl.b' boot-loader, your program must be small emough to
fit within 127 logical blocks on the disk.  (This requirement can easily
be met because you will not need a very large amount of code and data.)

		  SUGGESTED DEVELOPMENT METHODOLOGY

     It will likely be difficult to develop your entire project directly 
on our remote Core-2 Duo machines since you will not be able to view any 
debugging information, once you have entered protected-mode, until after
you have created a working version of your interrupt service routine for
for the serial-UART's interrupts.  (Indeed that's the very problem which
motivates us to tackle this programming assignment in order that we will
be able later in our course to explore 'Virtualization Technology' using
those remote machines.)  Therefore, we recommend developing a version of
your project for our classroom machines (using 32-bit protected-mode) as
a preliminary step, to get your interrupt-handler for the UART's console
redirection capability working properly before you try porting it to 64-
bit code that can only be executed for now on our Core-2 Duo platforms.
We will provide you with some code-samples to help you with this step.

			   WHAT TO SUBMIT

     Your project-submission will consist of two required parts: 
	(1) a paper-printout of your source-file (i.e., 'useisr64.s');
	(2) electronic copies of all three of your program-files; 
Use the 'ljpages' utility-program (under 'System Software' on our cs686
website) to produce your printout on a laserprinter in our classroom or
in one of the Harney Fifth-Floor CS Labs -- Be sure your printout shows
YOUR NAME as the project's programmer -- and turn in your 'printout' to 
the instructor's mailbox (Mathematics Office: Harney-222).  Submit your
three program files (i.e., 'useisr64.s', 'useisr64.o' and 'useisr64.b') 
by copying them into your '/submit' directory where your instructor can 
find them for doing testing and grading:

	 $ cp useisr64* /home/submit/cs210/<your_directory>/.
_______________________________________________________________________
Allan B. Cruse         University of San Francisco          Spring 2007